Full Name:  Lizzy de Vries
Username:  edevries@brynmawr.edu
Title:  Breastfeeding: Beneficial For Both Children and Mothers
Date:  2005-09-21 22:39:00
Message Id:  16257
Paper Text:
<mytitle> Biology 103
2005 First Paper
On Serendip

When raising a child, parents are forced to make countless choices, the outcome of which may or may not improve the wellbeing their child. Often one of the first of these questions addresses the issue of breastfeeding. The continual debate over whether or not mothers must breastfeed has inspired numerous studies and publications. Many of these studies have informed the public that while breastfeeding an infant is a customary and natural practice, it is not one which is absolutely necessary. While this information may provide relief to non-believers and working mothers, one cannot ignore the countless benefits which breastfeeding can provide. Not only is breastfeeding beneficial for babies, but for mothers as well.

The ingestion of human milk is crucial to the health of a baby. The immune system of a child does not reach its full strength until around the age of five, but many of the components of breast milk can help infants and young children to avoid disease in several ways. (7) The first of these components is secretory IgA, an antibody found in the gut and respiratory system of adults, and the most abundant type of antibody in breast milk. When the mother comes in contact with a pathogen, or disease-causing agent, she synthesizes antibodies specific to that agent only. These antibodies are passed on through breast milk, and the baby receives protection from the pathogens within its environment. Secretory IgA also fights disease without causing inflammation which might hurt healthy tissue. In addition to IgA antibodies, immune cells consisting of white blood cells, or leukocytes, are found in breast milk and help to fight infection. The most common milk leukocytes are neutrophils, which act as phagocytes and absorb harmful microorganisms in the infant's gut, and macrophages, which manufacture lysozyme, an enzyme capable of destroying the cell walls of certain bacteria. (7)

The health benefits for the breastfed infant go beyond the building of a strong basic immune system. Breastfeeding can provide protection against allergies, asthma, exzema, immune system cancers such as lymphoma, bowel diseases such as Crohn's disease and celiac sprue, and juvenile rheumatoid arthritis. (3) The mental and physical development of infants have also been proven to be affected by breastfeeding. Studies verify that infants who are breastfed begin to grow faster, then reduce the speed of their growth around their first birthday. The infant's brain and retinal development is assisted by DHA (docosohexaenoic acid) and AA (arachidonic acid), two ingredients of human milk. (3)

While the intake of the components of human milk is clearly advantageous to the health of the young child, breastfeeding can provide health benefits to the mother as well. Initially, the sucking of the infant causes recurrent bursts of oxytocin to be released from the mother's pituitary gland. The release of oxytocin causes the uterus to contract, protecting the mother from postpartum hemorrhage. (3) In the case of mothers with diabetes, those who breastfeed tend to need less insulin or medication, and may be protected from the progression of their disease, as a result of the efficient use of calories during breastfeeding. Milk production expends 200-500 calories a day, so mothers who breastfeed may find pleasure in a more rapid and lasting weight loss. (3)

Most beneficial to the health of the breastfeeding mother is the delay of the return of ovulation and menstruation. Delayed menstruation decreases the mother's iron losses and risk of iron deficiency anemia. (3) More importantly, the prolonged suppression of ovulation by an extended period of breastfeeding has been linked to long-term health benefits. One British study has shown that for each child carried, the risk of developing breast cancer by the age of 70 was reduced by 7 percent. For every year a woman breastfed, the risk of breast cancer fell by an additional 4.3 percent. (9) A reduced number of occurrences of ovarian and uterine cancers in mothers who breastfeed for at least six months throughout their life time has also been observed. (3) Another more recent study, published in The Lancet, concluded that the number of breast cancer cases in British women would be just half as large if they gave birth to six children and breast-fed them until they were two or three years old. Dr. Gillian Reves, a co-author of this study, said, "If women in the West were to breast-feed each of their children for an extra six months, this could prevent five percent of breast-cancers each year." (9)

In addition to the various health benefits, scientific evidence illustrates that breastfeeding is emotionally beneficial to the relationship between mother and child. The mother-child bond is strengthened by the combination of the hormonal effects of breastfeeding on a woman and the skin-to-skin contact and intimacy. One study found that in a developing country where there is a significant rate of the abandonment of children by their mothers, a smaller number of mothers abandoned their babies when breastfeeding rates were increased. (3) Some studies argue that the bond between mother and child is enhanced even more when an infant is breastfed because the infant is given greater opportunity to become familiarized with its mother's characteristic odor. After just a few days of breastfeeding, infants react preferentially to the odors of their own mother when exposed to these odors and similar odors from an unfamiliar lactating female. (6) Infants who are breastfed have also been found to be capable of identifying their mother by her breast odor alone. (1)

While I am sympathetic and understanding of those women who, for various reasons, are unable to breastfeed their babies, it seems to me that if one has the option of deciding whether or not to breastfeed, the choice is clear. In my research I have come across numerous health and emotional benefits, for the mother and particularly for the child. The decision to breastfeed would not only be the choice which I feel would be best for my child, but also the most personally satisfying. The opportunity to provide my child with additional protection from disease is one I could not pass up, and the chance to develop a more intimate bond seems to me to be irresistible.

Sources

1) Cernoch, Jennifer M. and Richard H. Porter. "Recognition of Maternal Axillary Odors by Infants." Child Development, Vol. 56 (Dec. 1985), pp 1593-1598

2)"Cancer Risk Falls If Women Extend Breast Feeding" , on the Jane's Breastfeeding Resources website

3)"Breastfeeding: Good For Babies, Mothers, And The Planet", on the Medical Reporter website

4) "More U.S. Women Breastfeeding Babies for Longer Durations." Family Planning Perspectives, Vol. 13, No. 2 (Mar. – Apr. 1981), pp 86

5) Macklin, Madge Thurlow. "Human Breast Cancer and the Milk Factor." Science, New Series, Vol. 104, No. 2694 (Aug. 16, 1946), pp. 168-169

6) Makin, Jennifer W. "Attractiveness of Lactating Females' Breast Odors to Neonates." Child Development, Vol. 60, No. 4 (Aug. 1989), pp. 803-810

7)"How Breast Milk Protects Neborns", on the Jane's Breastfeeding resources website

8)"Convenience and Replacement: The Pervasive Corporate Influence Over Breastfeeding", on the Serendip website

9)"Breast-feeding For Longer 'Cuts Risk of Cancer'", on the Jane's Breastfeeding Resources website




Full Name:  Nick Krefting
Username:  nkreftin@haverford.edu
Title:  Biological Classification Schemes and their Relation to Societies
Date:  2005-09-25 14:43:19
Message Id:  16287
Paper Text:

<mytitle>

Biology
103

2005 First Paper
On href=/>Serendip

Human beings naturally categorize their world, both as individuals and as groups or societies. When societies endeavor to classify their surroundings, this classification is inevitably a comment on that society in some way. In this way, the examination of a classification scheme can give some insight into the workings of a society. Granted, a given society's method of classification does not provide an entire explanation of the intricacies of that society. Rather, some of the prevailing beliefs and trends in a given society can dictate how that society organizes their world. For this investigation, the main classification schemes of the Western world will be taken into account with relation to their society's organization.

A good example of this is the so-called "Great Chain of Being," the predominant system of classification in Europe from about 0 CE to 1600 CE. Over this timespan, the Chain took on various forms and meanings. (1) One such incarnation of the chain is Didacus Valades' depiction, used and accepted in medieval Europe. In this system, organisms and non-living matter are organized in a hierarchy based on their relative perfection to God. (2) Angels fall right under God, and, after them, humans are the next most perfect beings.

Obviously, this system is based more in religion and philosophy than in what we would now call science, but it is nonetheless a window into the organization of the society. In fact, the two fit together nicely; society and this incarnation of the Chain complement and reinforce each other. The feudal governments of medieval Europe were arranged hierarchically as well – the royalty, perceived as the closest humans to heaven, consequently assumed the most powerful roles in the society. The word "pyramid" is often used to describe this feudal regime, with the king occupying the top point of the pyramid and the lowest-ranked lords on the bottom. (3) (4)

It is clear, then, that there was a direct link between biological classification and social organization in the minds of medieval people in Europe. Both were arranged strictly hierarchically with religious importance forming the basis of both. Despite this clear link, though, there is some disparity between the two organizational schemes, primarily because feudalism in Europe was hardly organized entirely on religion. Though it is true that the king occupied his place in the feudal pyramid due to religious beliefs, all non-royal lords occupied their respective places on the pyramid because of their land holdings and military service. (4) So while there was a natural order to the scheme of biological classification, there was very little perceived as "natural" within the feudal framework.

The transition from the Great Chain of Being to the modern system took a few hundred years. A more basic form of the modern system of binomial nomenclature was first utilized in the 16th century by Johann Bauhin and Gaspard Bauhin. The system was popularized by Carolus Linnaeus in the 18th century. (5) Though his system was less overtly religious than the Great Chain of Being, Linnaeus was deeply religious himself and devoted himself to finding the beauty of God's natural order in the world. (6) Linnaeus' system, then, was a middle ground between religiosity and rationality. He did not overtly classify one organism as better than any other, or as closer to God than any other, yet religion remained at the root of his system. Linneaus' work, when combined with Darwin's theory of evolution, was used by some to update the Great Chain of Being, creating a hierarchical system of organisms roughly based on complexity. (7) Obviously, humans were at the top of this hierarchy.



This progression of the classification scheme in some ways mirrors the trend in societal change. During the 16th and 17th centuries, the thinking of society moved away from the primarily religious theory that had been prevalent, and was in the midst of moving toward a more "science"-oriented way of thought that relied more on evidence and less on faith. People did continue to hold deep religious beliefs, but the public's thoughts on societal organization shifted away from the old hierarchical standard. The Renaissance was not a radical shift in social order, but rather signified a change in the way people thought about society. (8) Just as people came to demand more evidence in biological classification, people as a whole were starting to question the organization of society. Neither area of thinking changed immediately during this period; the Renaissance served as a long shift in ideology in both thinking about classification and thinking about society.

In modern times in the West, we use a drastically updated model of Linnaeus' taxonomy. The system has been altered to include the theory of evolution – organization is now based on common ancestry between species, not solely on appearances. (9) Theoretically, this serves to eliminate hierarchy in the system; all organisms are equally advanced in an evolutionary sense, and this system attempts to reflect that.

In modern Western culture, there seems to be a disparity between society's perceptions and our classification scheme. Theoretically, there is no superlative organism according to our updated system of binomial nomenclature; all organisms are equally good at survival at this moment in time, at least in an evolutionary sense. And while there is no prescribed hierarchy to organize our society, Americans seem to associate economic class with personal worth. Our idea of biological classification then does not seem to fit in with our idea of society.

Interestingly, though, there seems to be ambiguity in our society toward both class issues and biological diversity. Though class is not seen as prescribed, our society still puts more human worth in those with money. The same can be said about our current system of classification; although all organisms are evolutionarily "equal," humans still tend to see themselves as the "most advanced" organisms in the world. Certain communities accept this evolutionary equality, just as certain communities believe in and work toward social equality. Neither of these beliefs, though, is by any means the majority belief of our society. Perhaps, then, society is in the midst of a change toward a wider acceptance of people of all classes as it changes toward a wider understanding that humans are not at the top of any evolutionary tree.

From this discussion, it appears as if a society and its chosen system of classification are somehow linked, though perhaps the limiting eye of historical vision makes us see this link clearly in the Middle Ages. Our reality today suggests a much more strained relationship between these two, and the Renaissance is an ambiguous time of gradual social change. From knowledge of modern Western society, people appear to read what they want into a classification scheme – for instance, that humans are the ideal form of life – and so, in this way, our classification system can appeal to a wide variety of people in our society. This begs the question, will our system ever be fully understood and accepted universally, or will it always be this personal?

1) Wikipedia's Article on the "Great Chain of Being"

2) Didacus Valades' "Great Chain of Being", 1579

3) A History of Feudalism in Medieval Europe

4) A Definition of Feudalism , with an emphasis on Medieval Europe

5) Wikipedia's Article on Carolus Linnaeus

6) University of California Museum of Paleontology's Biography of Linnaeus

7) Hierarchical Evolutionary "Tree"

8) Wikipedia's Article on the Renaissance

9) David O'Neill of Palomar College's Principles of Classification



Full Name:  Katie Driscoll
Username:  kdriscol@brynmawr.edu
Title:  Two of a Kind: A Study of Identical Twins and the Environment
Date:  2005-09-25 19:13:56
Message Id:  16293
Paper Text:

<mytitle>

Biology
103

2005 First Paper
On href=/>Serendip


DNA testing has been used by law enforcement agencies around the world to convict the guilty and exonerate the innocent. Everyone's DNA is unique, making it the linchpin in solving many important criminal cases. At a crime scene, any remnants of hair, blood, semen or other bodily fluids are used by forensic scientists to profile and compare the DNA strands of the specimen to that of the suspect's (1). This seems like a flawless system: Simply match the DNA left at the scene of the crime with that of a suspect and there's your answer! Or is it?

Let's look at the case of Darrin Fernandez, who was arrested while breaking and entering a woman's house and tried to escape from the building while bleeding. The police took samples of his blood and found that the DNA from this sample matched the DNA obtained from two unsolved sexual assaults, each one taking place within a few blocks from where Darrin was arrested. Darrin was convicted of one of the two rapes, but could not be convicted of the second. In the second case, DNA was the only evidence recovered from the crime scene. In most cases, this would be more than enough evidence to convict a suspect. However, in this instance the DNA turned out to be a perfect match for two people: Darrin Fernandez and his identical twin, Damien (2).

Identical twins occur when a fertilized egg splits, creating two embryos with the same DNA, making it impossible to distinguish one twin from another using our current DNA analysis technology. Although identical twins only make up about 4/10 of 1% of the population and there are only between 3 and 10 serious criminal cases annually involving identical twins, it is still worth noting the apparent limitations of our DNA testing system (2).

However, recent research conducted by Mario F. Fraga, of the Spanish National Cancer Center, indicates that perhaps identical twins are not truly identical. Fraga studied 80 Caucasian identical twins from Spain ranging from ages 3-74, with a mean age of 30.6 years old and a standard deviation of 14.2 years. He used epigenetics to determine if there were any noticeable differences in the genetic makeup of these identical twins (3). In epigenesis, methyl groups are "added to specific sites on DNA and acetyl groups are added to the histone proteins that form the chromosomal structure around DNA, either silencing (through methylation) or promoting (through acetylation) the expression of specific genes" (4). In short, epigenesis relates to how genes are expressed by magnifying or reducing the effects of specific genes (5).

Fraga's results illustrate that in 65% of twins studied, there was no difference in epigenetic patterns on the DNA. However, 35% of twins exhibited epigenetic differences. Large epigenetic differences were associated with older twins who had different lifestyles, and had spent less of their lives together, illustrating the potential important role of environmental factors in creating epigenetic differences among identical twins (3).

Fraga's results have been useful for many fields of science, including psychiatry. Doctor Peter Roy-Byrne, Editor-in-Chief of "Journal Watch Psychiatry", recently published an article explaining the vital importance of Fraga's study in the field of psychiatry. He writes that Fraga's results can serve as a possible explanation for the frequency and onset of disease among identical twins. He explains that in the psychiatric field, psychiatrists study how one's experiences relate to one's genetic make-up to produce certain psychiatric illnesses. Doctor Byrne adds that Fraga's results can be of great use in explaining why some twins and siblings do not have the same illnesses and why some twins get the same disease but at different ages (4).

Fraga's study is important for understanding potential differences among identical twins and the idea that identical twins can actually have different expression of genes in their DNA is truly groundbreaking. However, I think that his research seems to raise the more important issue: How does the environment produce possible life-altering changes in DNA expression? Epigenetics can be an important tool to helping us understand the potential hazardous effects of the environment on all human being's health. It could be used to explain why a disease strikes one person and not another, even though neither one's DNA carries a disease-causing residue (6).

The notion that the environment can be a significant factor affecting one's livelihood, leads to me to question: Did we do bring this upon ourselves? The world we live in is not the same environment that our parents or grandparents lived in. Our world is constantly changing, especially as a result of developing technology and science. We have created this world, this environment that we are now finding may actually cause harm to us. For example, there are people who live near power plants, a man-made construction, who may be more prone to developing cancers and tumors as a result of living in this environment. While power plants do provide us with the energy needed to fuel our civil society, what are its effects on the people living near these plants? Is it worth exposing ourselves to these potentially hazardous environments for the sake of technology and the 'advancement' of our society? By advancing technologically, are we really progressing, or have we inevitably doomed ourselves to suffer the consequences of such 'progress'?

I realize that tests have been conducted in the past demonstrating that living in a particular environment and partaking in a certain lifestyle will inherently affect one's overall health. However, Fraga's observations really made me take a step back and put my own life in perspective in terms of my daily choices. I feel like we have tampered so much with our environment, from genetically engineering crops to building large nuclear power plants, to the point that we may actually be putting ourselves in more danger for the sake of science and capitalism. The idea that I am part of this general population that is affected by the environment makes me feel like a guinea pig in this technologically developed society that we live in.

Although Fraga's observations do not establish any Truths about science, his work will serve as a building block for progress and for further scientific exploration. His work does point out interesting differences between identical twins that could assist a wide-ranging spectrum of people in better understanding their field. Forensic scientists could work to create a new test that could use epigenetic differences to distinguish identical twins suspected in a criminal case. Doctors may be able to better understand why one twin may develop a disease much later than the other. On a much larger scale, it addresses the issue that our environment and personal lifestyle choices could play a major role in affecting our health. Furthermore, it leads one to question that in trying to 'evolve' and 'progress', have we only set ourselves up for self-destruction.

Sources


1) "DNA" on Wikipedia encyclopedia website


7) "Evil Twins." Legal Affairs Magazine. September/October 2005, pages 5-7.


3) "Epigenetic Differences Arise During the Lifetime of Monozygotic Twins" on the Proceedings of the National Academy of Sciences of the United States of America Website


4) "Emerging Perspectives: Epigenesis — How Experience Sculpts Genes" on the Journal Watch Psychiatry Website


5) "Identical Twins Exhibit Differences in Gene Expression" article on Scientific American website


6) "Twin Data Highlight Genetic Changes" Washington Post Article



Full Name:  Keti Shea
Username:  kshea@brynmawr.edu
Title:  Multiple Sclerosis: Auto-Immunity and Genetics
Date:  2005-09-25 20:07:06
Message Id:  16294
Paper Text:

<mytitle>

Biology
103

2005 First Paper
On href=/>Serendip

This paper is an exploration into the complexities of autoimmune disorders, in particular those related to multiple sclerosis. An additional focus is on the interplay between external factors such as one's environment and genetics in order to better understand the concept of auto-immunity. These questions lead us to a further question of the role of science and in what ways does science help in making new discoveries? Given that there is no known cause or cure for MS, in what ways, if any, is science adequate in understanding the complexity of autoimmunity?
MS is a well-documented disease, affecting around 300,000 Americans and is second only to head trauma as the most common neurological cause of disability among young adults (4). Symptoms of the disease vary widely but they generally include numbness of the limbs, fatigue, double vision and/or loss of vision, imbalance, incoordination, speech problems, loss of motor control and chronic pain (4). These symptoms can be chronic as is the case with MS victims of the progressive type or they can be intermittent as in those patients with relapse-remitting MS (4). The fact that these symptoms vary drastically, among individuals but also within the individual course of the disease, is one of the reasons that MS is so hard to treat. There is drug treatment but patients often respond differently, or not at all, and severe side effects may result (7).
While the symptoms of the disease vary, the population it attacks does not: the majority of MS sufferers are women of Northern European heritage (7). There is an extremely low prevalence of MS in populations of African blacks, Asians and ethnic groups with little Caucasian mixing.This is where the field of genetic becomes crucial; by researching and comparing chromosomal sites of MS victims and their families, these studies seek to address the question of why MS is so prevalent among Caucasian women between the ages of 20 and 50 (7).
In order to understand genetic studies involving MS, one has to first understand how the disease itself functions. MS is characterized by lesions on the brain, inflammations which occur due to demyelination. Myelin is a combination of lipid fats (80%) and proteins (20%) which sheath the axons, or nerve cells, in the central nervous system (7). Myelin affects the speed with which nerve signals (impulses) can move down the axons. In MS, this myelin is destroyed and can no longer act as an axon sheath, inhibiting the transmission of nerve signals and also leading to partial or total nerve damage . Myelin is destroyed by T-cells which recognize myelin as a foreign body and therefore destroy it; it is this process in which the body actively attacks its own cells which led to the designation of MS as an
autoimmune disorder
(7).
Genetic research is essential to understanding MS. It is a complex disorder, meaning that it is multifactorial and polygenic: it does not strictly follow Mendelian patterns of inheritance because there are multiple, interacting genes involved (3). This is complicated by the belief that each gene contributes relatively little to overall risk of susceptibility; it is only in the specific way in which these genes interact with one another and with the environment which triggers the onset of MS (3). Scientists have, however, been able to locate eight regions of interest at chromosomes 5, 6, 17 and 19. The regions are singled out as showing linkage to MS and were derived from family-based association studies which examine which alleles are transmitted to children through a test called the transmission-disequilibrium test (2). The interaction of multiple genes is further complicated by the fact that primary genetic heterogeneity can occur in those affected by MS, meaning that different genes can cause similar and even identical forms of MS (2).
Another interesting way in which genes are important to MS research lies in the
differentiation between susceptibility genes and modifier genes. For example, the HLA-DR2 haplotype at chromosome 6 has shown linkage to MS because of the way HLA alleles (a DNA coding of a single gene), respond to antigens (proteins) (2). These genes may not only influence susceptibility but also clinical symptoms such as how the disease develops and progresses and how patients respond to drug therapies. For instance, studies have shown that there is an association between the apolipoprotein-4 allele and the severe MS strains . Similarly, those patients in this group study who suffered from mild strains of MS contained a larger percentage of the APOE-2 allele carriers (2). This means that a carrier of a certain allele may experience symptoms differently than someone who carries a different allele.
Additionally, past studies conducted on twins shows a linkage between genetic make-up and disease susceptibility. For example, the rate of susceptibility of the general population is 0.1% while for siblings and fraternal twins it is about 5% . But while there is an increased susceptibility for those related to MS victims, genetics is not the exclusive factor. If that were so, there would be a concordance rate of nearly 100% for identical twins. This is not the case. This suggests then that genetics may contribute to susceptibility but there are other environmental (and unknown) factors which trigger the onset of the disease. This trigger is as yet
unknown but is believed to be a virus or bacteria of some sort. The Multiple Sclerosis Genetics Group puts it thus, "....it is also likely that interactions with infectious, nutritional, climatic, and/or other environmental influences affect susceptibility considerably. This complex array of factors results in a severe disregulation of the immune response, loss of immune homeostasis and self-tolerance..."
(7). In other words, while scientists have been able to identify linkage in certain chromosomal regions, the complex interplay of factors which affect such things as age at disease onset, intensity and duration of symptoms and reaction to drug therapy, combine in such a way to make MS unpredictable.
An additional point of interest that this citation brings forth is the idea of "self-tolerance" or auto-immunity. How exactly does one respond or deal with instances when the body actually turns on itself? This is the question which science now has to try to answer. There is treatment for MS but there is no cure or any known cause. This leads us to the question of the role of science and more specifically, are there some questions which science simply cannot answer?
As one Biology student comments in her paper "MS and the Self": "People guard their
mental functioning closely. However, when the cognitive problems of MS set in, they may find that they have lost hold of that which they consider to encompass "self" (1). Her point is a good one in that it comments on the psychological implications of this disease which is at once mentally and physically debilitating. It is also profoundly debilitating psychologically due to its inherent unpredictability. The occurrence of MS and other autoimmune disorders directs our focus to the workings of the human body, those biological processes which (healthy) humans take for granted. It is these processes which we are unaware of; like breathing and winking, the body performs numerous and intricate tasks without us even realizing. But what happens when the possibility of malfunction, of human error in a quite literal sense of the expression, takes place? This is the most debilitating realization that can be drawn:
the realization that one's body and its mechanics are faulty, that what is "alien" and what is "self" are not distinguished by the brain. Here is a breakdown of communication at the most basic level- not between individuals, but within them, at the cellular level. And all this is beyond one's control.
In conclusion, some comments were made in the course forum area which described
science as useful despite its weaknesses. We can debate its truthfulness or its accuracy but its utility as a way to describe and understand how and why things happen remains essential (5). This is true even in the case of MS. There may be gaps in scientific knowledge but this is not to say that science loses its value as an exploratory tool. Studies in MS have shown how scientific research leads to new questions which lead to further research. Although many questions concerning MS remain unanswered, these unanswered questions lead to further explorations in the field of auto-immunity.

Sources:
1)Multiple
Sclerosis and the Self
, can be found on Serendip website.

2) Multiple
Sclerosis as Genetic Disease
.

3)Genetics and
Multiple Sclerosis
.

4)Multiple Sclerosis: The Immune System's TerribleMistake.

5)Biology 103 Forum area, on the Biology 103 website.

6)
Genetics- The Basic Facts
, on the National MS Society website.

7)
Research Directions in Multiple Sclerosis
, on the National MS Society website.



Full Name:  Magdalena Michalak
Username:  mmichala@brynmawr.edu
Title:  Hantavirus
Date:  2005-09-25 21:35:00
Message Id:  16296
Paper Text:
<mytitle> Biology 103
2005 First Paper
On Serendip

I did a paper on viruses in high school and I remember being particularly bothered by hantavirus (hantavirus pulmonary syndrome or HPS), even more so than by any of the various Ebola strains, because of its prevalence in the USA. I wanted to take this opportunity to dig a little bit deeper into what hantavirus was, how it was spread, and its impact on people.

HPS is a fairly new disease. The first outbreak that really gave rise to headlines was in the summer of 1993 in the Four Corners area when five young, healthy people died of it. The first known victim of HPS was a 38-year-old man who died in 1959. Hantavirus is spread by mice, particularly deer mice, and the explanation for the 1993 outbreak was the huge increase in mouse population (greater mouse density amounted to greater chance of human-mouse contact, and therefore greater likelihood of the disease being transmitted) caused by heavy rainfall and therefore a bumper crop of grains which gave mice plenty to eat and led to their rapid reproduction—a tenfold increase from May of 1992 to May of 1993.

Hantavirus doesn't affect the rodents which carry it. These rodents include deer mice in the southwestern states, cotton and rice rats in the southeastern states and white-footed mice in the northeastern states. The virus is expelled through urine, droppings, and saliva of rodents—it can't be spread person-to-person in the same way that many other pulmonary diseases can be. The disease is mainly spread when the virus becomes airborne when dried droppings or urine are stirred up, most commonly by the simple act of sweeping a dusty corner. There is also a possibility that the virus can be spread by bites from infected rodents and by ingesting contaminated food.

People at greatest risk for contracting HPS are those living in areas of high rodent populations and who are cleaning places such as cabins, sheds, barns, and garages which haven't been used by people for a time, especially in rural settings. It's basically a good idea to take precautions whenever performing such activities to minimize the risk of contracting hantavirus. Some HEPA-approved masks provide limited protection from hantavirus, but the virus is small enough to get through most filters. The best prevention method is eliminating rodents from the immediate area and thereby preventing the presence of the virus rather than attempting to rectify the situation later. Sealing up gaps in the home, placing rodent traps in areas where rodents might be trespassing, and not keeping food items (including bird and grass seed) where they're accessible are good, basic preventative measures.

The symptoms of hantavirus include fatigue, fever, and aches in the thighs, hips, and back. Sometimes the symptoms also include headaches, dizziness, chills, and abdominal problems. Later symptoms of the disease include coughing, shortness of breath, and inability to "fill" the lungs with oxygen (caused by the lungs filling with fluid). Treatment is non-specific and is therefore supportive—intubation, oxygen therapy, and anti-inflammatory drugs help, and the sooner a patient is taken to intensive care, the better their odds of recovery. The mortality rate for hantavirus is 50%, making it a serious illness. With most viruses, people with weakened immune systems have a higher risk of contracting the disease; hantavirus is virulent enough that even young, healthy people who aren't immunocompromised are just as susceptible as older people with more fragile immune systems.

As of right now, hantavirus has been found in roughly half of the states in the USA as well as in South America and parts of Canada. This makes it a panhemispheric disease; so far, hantavirus hasn't been found on other continents.

What strikes me as particularly interesting about hantavirus is that it isn't a more common household name. I think most of us grow up knowing that there's something "bad" about mouse droppings (rather than just the general distaste over the fact that they're droppings) but hantavirus isn't something we learn about, whereas things like Lyme disease and West Nile Disease/West Nile Encephalitis are things everyone knows about. I suppose part of that is the relatively small number of cases that have occurred—roughly 2,600 as of May 2003—and another part may be that it's a rural disease and therefore not given the same type of attention that a more urban disease (such as West Nile Encephalitis, which first showed up in New York City) might get. Another factor might be that HPS isn't spread from person to person, but neither are Lyme or West Nile. All in all, I think it's an important disease to be aware of, and one that should be treated by name. The more it's de-mystified and explained, the better a chance that less people will contract it in the future.

http://www.cdc.gov/ncidod/diseases/hanta/hps/index.htm: The CDC (Centers for Disease Control) site on hantavirus.
http://www.doh.wa.gov/topics/hanta.htm: The State of Washington Department of Health site on hantavirus (a bit more state-specific information).
http://www.hantavirus.net/: A general website with some supplementary information as well as a few more numbers, though the CDC site is more thorough.
http://www.nlm.nih.gov/medlineplus/hantavirusinfections.html: The MediaLine Plus site, a bit more medicine-intensive/healthcare-oriented.




Full Name:  Zach Withers
Username:  zwithers@haverford.edu
Title:  Brain-Machine Interfaces: An Upgrade to Nature's Design?
Date:  2005-09-26 01:11:56
Message Id:  16302
Paper Text:
<mytitle> Biology 103
2005 First Paper
On Serendip

Brain-Machine Interfaces, or BMI, are an attempt to artificially replicate the electrical-to-mechanical translation done naturally in animal muscles. The technology, as it currently stands, consists of electrodes placed in the brain to pick up the signals traveling down individual motor neurons. It has been found that this can be done by "polling" the neurons – taking a sample of the neurons you want, and extrapolating the signals in the rest of them. Like any poll, there is a margin of error. Also like any poll, the population of neurons is simply too large to ask them all. The process works by analyzing the subject's neural activity – what firing neurons correlate with what moving limbs? When that relationship is well understood, the BMI can then extrapolate what movement the subject intends based on which neurons are firing, and replicate that intended motion with an outside mechanical object. (1)

The seminal study in the field of BMI was run in the mid 1990s at Hahneman University, when researchers wired a rat's brain with electrodes and taught it to control a lever with its mind. The rat was taught to push a bar for water; the bar was connected to a lever, which was connected to a button which dispensed the water. As it did this, its brain functions were recorded. After some time, the mechanism on the lever was changed. It was disconnected from the bar; rather, it was computer controlled, and the computer was connected to the rat. Now, rather than pushing the bar, it had to think of whatever it was thinking when it pushed it before. It worked. Despite initial frustration that the bar was no longer working, the rat eventually figured out how to get the water flowing again. Soon, it wasn't even touching the bar, simply looking at it from across the room, and presumably imagining touching it. (1)

As computer technology improved through the early 2000s, more sophisticated studies were done, first using smooth-brained spider monkeys, where computers were able to accurately predict the monkeys' arm movement from its neural signals and make two robotic arms move in synchrony with the monkey's, and later with wrinkle-brained macaque monkeys, which were first taught to hit targets on a screen with a joystick – and later, to hit them by thinking about using the joystick. (1)

At present, the studies have advanced to humans. One of the hoped for products of this technology would be the restoration of limb movement, or at least some way of interacting with the world, to paralyzed individuals. At least two studies are currently underway in this direction, one at the University of Freiberg, and one joint project between Brown University and Cyberkinetics Corp. (2) (5) The Cyberkinetics study appears to be making excellent progress – they report a 25 year old quadriplegic has successfully been able to switch on lights, adjust the volume on a TV, change channels and read e-mail using only his brain, and was able to do these tasks while carrying on a conversation and moving his head at the same time. (4) The original project for more realistic prosthesis continues apace as well, as a team at Pitt has designed a BMI-prosthesis assembly precise enough to allow a monkey to pick up and eat food using only the robotic arm. (3)

As with so much of new technology, the military is one of the greatest backers of BMI. Some military uses of BMI seem fairly logical, such as directly integrating a pilot with his aircraft. (4) Pilots have long said that after a while, their machines feel like extensions of their body. Why not make it literally true? However, the military seem to be going well beyond this scope. If Cyberkinetics seems inspired by Luke Skywalker's prosthetic hand, the Pentagon is more intrigued not by the Terminator, but by Neo's knowledge of kung fu. DARPA's Eric Eisenstadt described a few of the military's goals for BMI in a recent speech. The projects he describe are far from what I would expect. Rather than building armies of invincible machine men, Eisenstadt wants to use the technology to prize data out of the biological brain. He talks of implanting electrodes into bomb-sniffing dogs' olfactory lobes to determine exactly what it is they are smelling, of perfect lie detectors, of directly recording datastreams from soldiers' minds. Also of interest to the Pentagon – and a project they have already begun and shown results from – is reverse-BMI, the translation of artifical nerve stimulus into a real brain, rather than real nerve stimulus into an artificial limb. Dr. Eisenstadt showed his audience a movie of "roborat", a real rat putting itself into highly unlikely positions, due to instructions being fed to its motor neurons through BMI. (6)

BMI, in its medical form, raises few if any moral qualms for me. I simply fail to see the difference between the brain's controlling a meat limb and a robotic one. Even the Pentagon's more straightforward projects don't really phase me. A pilot mentally fusing with his aircraft may be kind of weird, but it's only a natural extension of what they already do – what anyone using a tool does. The projects deeply involving themselves with the internal workings of the mind, on the other hand, deeply disturb me. Unquestionably, knowledge is power, and the military needs all the power it can get. Nonetheless, there is some power that I would not grant it, and power over the mind is one of those things. Even more disturbing than the fact that they might use these things on the enemy is that that they might use them on our own soldiers. An army of automatons would unquestionably be more efficient than an army of men, as long as the processes involving decision-making were left untouched. Brainwashing has always been a military trademark, but there has always been limits to it. If given unlimited access to a soldier's thoughts, I worry what the army would turn them into. These projects, however, pale in contrast to the Roborat experiment. This is just monstrous. A simple baseline fact of the world has always been that you can't make anyone do anything. You can ask, tell, beg, plead, cajole, and threaten, but in the end, they have to do it. The implications of Roborat alter this fundamental principle.

One has to question where BMI is taking us. The promised medical benefits and the question of whether we can decode neural impulses are simply to great to ignore – this is not a line of research we simply can close down. It also is one with which we must proceed with great caution.

Works Cited

1. Controlling Robots with the Mind - Scientific American article by leader of Duke monkey experiments
2. Brain-Machine Interface - Project C5 - Synopsis of project to develop BMI for prosthetic limbs
3. Scientists demonstrate a mind-controlled future - Account of U Pittsburgh BMI study
4. 'Briangate' Brain-Machine-Interface Takes Shape - Description of Cyberkinetics Co, and their prototype BMI for quadriplegics
5. Cyberkinetics Inc. - Company referenced above
6. Remarks by Dr. Eric Eisenstadt - Speech by DARPA manager on military applications of BMI
7. The Brian-Machine Interface – Paper on BMI by U South Carolina
pre-med Nidhi Kuma
8. Monkeys Adapt Robot Arm as Their Own - Duke University Press Release



Full Name:  Brom Snyder
Username:  msnyder@haverford.edu
Title:  Walking with a Loaded Gun: Pandemics, Genetic Engineering, and Chimp Meat
Date:  2005-09-26 02:14:14
Message Id:  16304
Paper Text:

<mytitle>

Biology
103

2005 First Paper
On href=/>Serendip

The increasingly interconnected global community is ripe for a pandemic. Scientists across the globe engage in experiments which slightly modify the structure of viruses, adding a gene here or there with unintended consequences; an increasing number of bacteria prove to be resistant to antibiotics; the ever expanding need for resources drives humans farther into previously uninhabited environments exposing man to a whole new army of viruses and bacteria; all of these factors combine with an unprecedented mixing of people as worldwide travel becomes more frequent, creating an environment where a pandemic is a serious threat.

Some members of the scientific community believe the greatest threat of a "super virus" comes from research involving genetic engineering. Dr. Mae-Wan Ho, a member of the Institute of Science and Society, states that there is great "danger in the unintentional creation of deadly pathogens in course of apparently genetic engineering experiments." (1) Her fears seem to be based on events like the accidental creation of a lethal mousepox virus in an Australian lab. Australian scientists were using the mousepox virus as a vehicle to insert a gene which would in turn produce a chemical making the mice infertile. The results were disastrous; the modified mousepox virus killed all the mice that had not been vaccinated for mouse pox, and fifty percent of the mice who had received the vaccination. The chemical produced by the injected gene suppressed the mice's immune system allowing it to be overrun by the virus. (2) While this is only one case and in this case no humans were harmed it is a model case of what can go wrong when perfectly innocent genetic engineering of viruses is conducted. If a person or group of people is looking to genetically modify an already existing virus in an attempt to make it more lethal there is a strong chance of success.

Not only do innocently and maliciously genetically engineered viruses pose a pandemic threat but bacteria which have evolved in response to the antibiotics used against them for the past sixty years do too. Bacteria like Streptococcus pneumoniae (the bacteria that commonly causes what is called strep throat) "easily acquire, integrate, and express stretches of DNA" causing the bacteria to mutate. (3) One of the most effective ways bacteria evolve is based on their ability to change the nature of the membrane that surrounds them. Bacteria decrease the size of the pores through the membrane making it harder for the antibiotics to get into the bacteria itself thus preventing its destruction. The problem confronting scientists is they do not know what new type of molecular mechanism will develop in the bacteria, if the mutation changes the structure or composition of the bacterium then a new antibiotic is necessary.(3) This factor makes it difficult to take preventative action. Scientists and researchers are in constant competition with the bacteria, and the odds are in favor of the bacteria. Organizations like the Center for Disease and Control are pushing for more discrete use of antibiotics but this is not a permanent solution, only one that might slow down the rate of mutation in bacteria. (4)

The need for food, resources, or land, particularly in areas of Africa, also help create an environment where a pandemic is more likely. Outbreaks of Ebola, one of the deadliest viruses man has encountered, with a fatality rate ranging from 50% to 90%, seem to be linked to men being out in the jungle for mining expeditions or hunting for animals like chimpanzees. (5)(6) As the population grows and more resources are needed environments like the jungle will be penetrated by man, and while this may prove a boon to mankind, unexplored areas offer unexpected benefits, a new plant that will be a key component of a new cancer drug, encounters with viruses like Ebola are likely to be more frequent. This problem is compounded by the fact that modern air travel makes it possible for someone to fly from Zaire, with a stopover say in Paris, and then to New York in a day. If a person were to be exposed to Ebola and then immediately leave the area it would be days and thousands of people later that he would show symptoms.

The evidence I present in this paper illustrates that in many ways the present situation regarding the potential for a pandemic is of man's own making. Genetic engineering, the over prescription of antibiotics, and the expansion of man into inhospitable environments all directly contribute to the rising threat of pandemic. The threat of a pandemic illustrates the true nature of scientific investigation. With the advances in scientific research that save millions of lives and make the quality of life better for countless others, comes the threat of new and unforeseen dangers. Science offers no final solution, as science advances it creates a new set of problems. That being said, it is impossible to stop the advance of scientific thinking because humans have the mental capacity to solve problems and have the ability to think abstractly about a "better life." These two factors fuel science but it should be remembered that with this "better life" comes with a whole host of new problems.


Works cited:
1)Institute of Science and Society News, Ho, Mae-Wen"Genetic Engineering Super Viruses" July 2001

2)New Scientist Magazine, Nowak, Rachel "Killer Virus" January 10, 2001

3)Center for Disease and Control, Courvalin P. "Antimicrobial drug resistance: 'Prediction is very difficult, especially about the future'" October 2005

4)Center for Disease and Control "Snort. Sniffle. Sneeze. No Antibiotics Please!" January 28 2005

5)National Geographic News Lovgren, Stefan "Where does Ebola Hide?" February 19 2003
6)Center for Disease and Control "Ebola Hemorrhagic Fever Table Showing Known Cases and Outbreaks, in Chronological Order" November 26 2003



Full Name:  Norma A
Username:  naltshul@bmc
Title:  Understanding the Clitoris Historically
Date:  2005-09-26 09:18:52
Message Id:  16308
Paper Text:

<mytitle>

Biology
103

2005 First Paper
On href=/>Serendip


Physiologically, the clitoris is crucial to female sexual pleasure; culturally, narratives about the organ's structure and function illuminate sexual mores, women's roles, and social agendas. Anatomical understandings of the clitoris have been shaped by social factors, but scientific stories about the organ and other aspects of women's sexuality have been invoked as social attitudes change. In this paper, I will trace the history of the clitoris in the West, including outlining our contemporary anatomical understanding of the organ. This description is including in the body of the paper to avoid privileging our contemporary understanding given this paper's historical approach, but at times I rely on the lens of modern anatomy. Increased accurate information about the clitoris in anatomy's terms has not necessarily corresponded to greater sexual liberty.

In ancient Greece and Renaissance Europe, mainstream society considered women as lesser or deformed men; contemporary understandings of female genitalia supported this conception. The ancient Greek physician Claudius Galen argued that women and men had differently located, but essentially equivalent genitalia. As the more perfect sex, men had sufficient body heat to allow genital protrusion, while weaker women's genitilia remained hidden from view. Galen's idea of equivalent anatomy persisted until the discovery of the clitoris in the seventieth century, when two Italian anatomists, Gabriel Fallopius and
Renauldus Columbus, separately claimed to "discover" the organ. Apparently these men did not consider women's experiences of the clitoris sufficient; "discovery" meant men's scientific understanding. Eighteenth century Europe reconceived of gender as binary, and began to think of men and women as separate sexes as anatomists produced detailed depictions of women. These shifts in thought were not mobilized to empower women. Rather, they corresponded to an increasing social sentiment that women were weak, irrational and intellectually inferior. Even as society reconceived of gender and established the category of women, it still understood menstruation as an illness. Major Enlightenment thinkers such as Jean-Jacque Rousseau and Charles Montesquieu thought that women's hidden passion had the potential to disrupt social stability. Later, as most anatomists reconceived of the clitoris as part of women's reproductive or urinary systems, the concept of women's sexual pleasure faded (1).

Sigmund Freud saw the clitoris as a sexual organ, but believed that clitoral pleasure represented an immature stage of development. Freud believed that young girls equate the clitoris with the penis and engage in clitoral masturbation. When a girl realizes that she and her mother lack phalluses, she ceases clitoral masturbation out of embarrassment at her inferior equipment and turns away from her mother; sexual attraction shifts to the father (2). For a woman to achieve maturity, she must shift her sexual experiences to her vagina (3). Freud's understanding of the clitoris propels important aspects of his larger theory, including the Oedipal complex. His understanding of female sexuality normalized heterosexual intercourse. Rebecca Chalker and Anne Koedt argue that Freud set the stage for the following century's grounding of female sexuality in male preference, although the history outlined above suggests that this concept had far deeper roots ((1) and(4) ).

As 1960s and 1970s feminists articulated a new vision of female sexuality,
they mobilized a new vision of the clitoris. Anne Koedt argues, in direct opposition to Freud, that the site of female orgasm is always the clitoris, even when women experience vaginal stimulation – thus the clitoris should be the site of female sexuality. The longstanding myth of the vagina orgasm, Koedt argues, is rooted in patriarchal systems that confuse women about their bodies and subordinate female sexuality to male pleasure. In light of her new understanding of the clitoris' function, Koedt calls on her readers to rethink sexuality and normalize new practices that ensure all parties' pleasure ((4)). Influenced heavily by Koedt's essay "The Myth of the Vaginal Orgasm," which was distributed at the 1968 Women's Liberation Conference, feminists centered their narratives designed to change sexual norms on the clitoris. Physiologically equating the clitoris with the penis as the site of sexual pleasure legitimized female sexuality; these women saw themselves as deconstructing traditional conceptions of female sexuality based on reproduction or male pleasure. Intertwined with this agenda for sexual change were attempts to enact political change by empowering women and changing their social roles ((5)).

Today, mainstream scientific sources describe the clitoris' sole purposes as sexual pleasure, and provide basic information on the clitoris' structure. Generally two to three centimeters long, ((6)) the human clitoris is composed of two corposa carnova, or sponge-like areas made of caterpilary tissues that contain numerous nerve ending. ((7)) Human sexual organs develop from a part of the fetus called the genital tubercle. If the fetus is male, the tubercle becomes the penis. In females, it initially grows into two separate corposa carnova, which combine into the clitoris as the fetus develops. The exterior and easily sexually stimulated portion of the clitoris is located above the vagina's opening. ((6)) With 8,000 nerve fibers, the organ is the most sensitive point on the human body, making it particularly well equipped for its sexual function. ((8)) This singular function distinguishes it from the penis, which also serves urinary and direct reproductive purposes ((3)).

This understanding, compiled from brief anatomical descriptions, provides scientists and laypeople with useful basic information. However, it also normalizes this version of genitalia at risk of alienating those born with different structures. Those who write such descriptions would do well to acknowledge variation. Additionally, Modern science does not always afford the clitoris adequate, or even accurate attention. A recent study suggests that many textbook descriptions lack detail or contain errors ((9)). I intended to give more attention to the clitoris from a biological perspective, but had trouble locating information about the clitoris in my library and internet research. More sources must exist, but my trouble locating information about issues such as the clitoris' role in physiological arousal is telling.

Feminists today continue to invoke the clitoris as a source of female sexual power today, sometimes including scientific or historical descriptions. In an important passage from her 1999 book "Women: An Intimate Geography," Natalie Angier's makes female sexuality powerful and mysterious through a portrait of the clitoris. Beginning with a personal anecdote, Angier argues that women do not engage with the issue of clitoris size; that they do not know what scales to think on, or what, if anything, size implies. She goes on to intertwine scientific description with poetic language, and portrays the clitoris a mysterious organ that defies medical efforts at complete understanding or control. For Angier, understanding the clitoris scientifically is important, but one must also realize and rejoice in its limitations. The clitoris' mystery and defiance are, she argues, empowering ((8)). Two other recent works cited above, Chalker's The Clitoral Truth and Segal's Straight Sex invoke anatomical and historical descriptions to reclaim the clitoris as a source of female sexual power.

If we take mainstream anatomy's current understanding of the structure and function of the clitoris as correct, there is no linear relationship between how accurately a society or writer understandings the clitoris and the sexual role it or she prescribes for women. More accurate information has not necessarily corresponded to greater sexual liberation. Most people in ancient Greece thought of women as deformed men, but that society acknowledged female sexual pleasure more than later Europeans who better understood female anatomy. For some feminists, the scientifically dubious claim that women cannot orgasm vaginally proved empowering. The contemporary lack of scientific attention to the clitoris may be indicative of attitudes towards women's sexuality, but attempts at social change must be coupled with other strategies besides increased research. Scientific understandings alone cannot create social change; indeed, scientific conceptions of the clitoris cannot be separated from social forces. Understandings of female anatomy are deeply embedded in cultural attitudes about women's sexuality; scientific stories are created and read under social influences.

1) Chalker, Rebecca. The Clitoral Truth: The Secret World at Your Fingertips. New York: Seven Stories Press, 2000.
2) an excerpt from Freud's Introductory Lectures on Psychoanalysis
3) an excerpt from The Oxford Companion to the Body on the clitoris in history
4) the text of the essay "The Myth of the Vaginal Orgasm"
5 Segal, Lynne. "The Clitoral Truth" from Straight Sex: Rethink the Politics of Pleasure. Berkeley, University of California Press, 1994.
6) an Encyclopedia Britannica article on the clitoris
7) a Wikipedia article on the clitoris
8) an excerpt from Women: An Intimate Geography
9) the abstract of an article entitled "The Anatomy of the Clitoris" from the Journal of Urology



Full Name:  Stephanie Hunt
Username:  shunt@brynmawr.edu
Title:  Factors influencing multiple sclerosis
Date:  2005-09-26 09:22:19
Message Id:  16309
Paper Text:
<mytitle> Biology 103
2005 First Paper
On Serendip

Multiple sclerosis (or MS) is an incredibly frightening disease that belongs to the class of diseases known as autoimmune disorders. MS is a chronic neurological condition that affects the central nervous system and essentially causes it to deteriorate slowly. The areas that can be affected by MS are muscle control and strength, balance, vision, sensation and mental functions (1). One of the reasons that this disease is so frightening is that it occurs in younger adults. With an onset typically between the ages of 21 and 40 (1), this is a disorder that causes numerous people to be dependent upon others for care and financial stability for a large portion of their adult lives. Needless to say, the emotional affects of MS are great on the patient and his or her loved-ones. Initially, I had planned to find out what it is that causes MS, but as I began to sort through MS information, I realized that this question was not one that will be answered any time in the near future. There is, however, a great deal of information on the factors influencing MS and through evidence for these factors, we may be able to gain a better understanding of multiple sclerosis.

Before being able to understand how these outside factors affect various aspects of multiple sclerosis, it is imperative to have a basic understanding of how the disease progresses. MS is the process of demyelination and subsequent disruption of nerve impulse flow, as nerve impulses flow through the myelin sheath of neurons (1). T cells, a subset of white blood cells, recognize parts of the central nervous system as foreign and attack the myelin sheath (2). The cells that create myelin (oligodendrocytes) are also destroyed in the process (1, 2). Progenitor cells migrate from other places in the brain and replace the myelin, but new myelin sheath is not as large or effective. This process of remyelination causes periods of time when symptoms are not present, but as the disease progresses, remyelination will eventually become impossible (2). There are four types of MS: relapse-remitting (symptoms fade and recur at random), secondary progressive (begins at relapse-remitting but progresses over time), primary progressive (progressive from start), and progressive relapsing (progresses from start but symptoms appear randomly) (1). The differences in these paths are important for implicating how patients can best be treated.

The first subject to be addresses in answering the question of what factors influence multiple sclerosis is who is affected by multiple sclerosis. MS affects 2.5 million people worldwide and about 1 in 1,000 people in the United States (1). Genetics seems to be an important factor in the epidemiology of MS. There is a higher risk for people with a family who has MS (1) and twin studies show that there is a 50% concordance between identical twins (who share all of their genetic make-up) while there is only a 5% concordance between fraternal twins (2). This is an extremely significant difference, however, no single gene is responsible for MS but a few genes may be correlated with increased susceptibility (2). A gene called neuregulin was recently found to be the "switch" responsible for producing myelin (5). As previously stated, the onset of MS symptoms is generally between the ages of 21 and 40, peaks at 24 and is very rare, but not impossible, prior to the age of ten and after the age of 60 (1). Women are three times as likely to develop MS, indicated that it may be linked to sex hormones (1). Another extremely interesting piece of evidence is that instances of MS increase as the distance from the equator increases in the northern hemisphere (1). Generally speaking, people of Western European ancestry are more likely to develop MS than other ethnic groups and those who are particularly immune to MS include, but are not limited to, Native Americans, Eskimos and Africans (1).

Naturally, the next question seems to be "why are certain people more likely to develop MS than others?" Although there is little concrete evidence about this matter, multitudes of theories and evidence to support them have been proposed. It was mentioned before that people farther north of the equator may be more susceptible to MS. It has also been found that if a person lived in one of these colder environments before age 15, even if they moved to or from such a climate, they had a greater risk of developing MS than a person who had lived in a warmer, sunnier climate until age 15 (1). One of the reasons that could explain this is the amount of sun exposure that they receive. The body produces vitamin D when exposed to the sun which has been correlated with the reduction of MS risk (6). A preliminary study showed that women who take vitamin D supplements are 40% less likely to develop MS (2). Further evidence for this comes from the finding that fair-skinned people are at greater risk for MS than darker-skinned people (6). This evidence in inconclusive in that it has no reasoning behind why sunlight and vitamin D affect multiple sclerosis, only that there is a negative correlation between instances of MS and the amount of sunlight that a person receives.

Another theory about the etiology of MS regards the immune and nervous systems during childhood. It is suggested that there is a possible structural similarity between unidentified infectious agent and components of the central nervous system causing confusion in immune system later in life, called molecular mimicry (2). These infectious agents could be a viral infection during childhood as there is evidence that viral infections can trigger an autoimmune reaction where the immune system attacks its own myelin sheath (1). Obviously, this type of hypothesis would be hard to study as viral infections during childhood are extremely common and it is difficult to predict which children might develop MS and would thereby be candidates for study.

One of the most compelling factors affecting MS is estrogen levels. We already know that women are about three times as likely to develop MS than men. According to studies, levels of estrogen and testosterone are the only sex hormones that have an impact on MS. Women with MS were found to have significantly low levels of testosterone, while men with MS were found to have levels of the hormone similar to those of men without MS. However, men with MS and have higher levels of estradiol, a form of estrogen, have more damage to the central nervous system (7). Further evidence for this hormonal influence comes from the use of oral contraceptives, which typically contain estrogen. Women taking oral contraceptives are 40% less likely to develop MS (4). Also, the risk of MS onset is lower during pregnancy, when estrogen levels are high, but in the six months following pregnancy, the risk is increased dramatically (3). This six-month period is when estrogen levels drop after delivery. This evidence is also in concordance with previous studies on other animals: high levels of estrogen prevent and ease the symptoms of MS (3). What is incredibly striking about this evidence is something so extremely obvious, yet does not seem to have been addressed in any research or articles: if high levels of estrogen prevent and ease the symptoms of MS, why is it that women are three times as likely to develop MS than men? One would think that the opposite would be true: men, who lack high levels of estrogen, would be more likely to have MS than females who do have high levels of estrogen. There is little information on why estrogen has this affect on MS only in women. Another topic that these findings raise is the specific effect of estrogen on the immune system. In researching the topic, there is only information stating that estrogen modifies the immune system in some way, but it is uncertain as to in what way and how. Clearly, there is much more research to be done on the affects of estrogen on MS.

In addition to these factors, there is a plethora of other theories concerning the etiology of MS. Research in Sweden shows that some forms may be linked to a rare allergic reaction to mercury in dental fillings. One can now be tested for this allergy and if the results are positive, the fillings can be done with ceramic fill (2). Another study showed that the month in which a baby is born may affect his or her development of the disease. Babies born in May have a 13% increased risk compared to babies born in November (8). It has been proposed that iron in the brain can cause symptoms of multiple sclerosis. If this is the case, it is likely that there will be a treatment for this in the near future (9). Another factor that may be a culprit is smoking. Although it is not known whether smoking increases overall risk of developing multiple sclerosis, studies show that MS patients who smoke cigarettes or have smoked cigarettes in the past are more than three times more likely to have a rapid progression of MS than those patients who have not smoked (10). These are some of the more interesting theories about the etiology of MS, but they are certainly not the only ones out there. Some of them seem so arbitrary that it makes one wonder how researchers decided what factors may be important to research and why. None of the articles suggested that there was any underlying evidence for why these factors were chosen over others. It calls into question the whole research process: how were these hypotheses formed? What prior observations were made to indicate that these factors were worth investigating?

The variation in findings of factors linked to multiple sclerosis demonstrates the lack of knowledge there is about the specific causes of the disease. It seems that the strongest arguments are for hormonal influences as well as amount of sunlight a person gets, but clearly there are other factors affecting the development of MS. All of these factors need to be investigated to discover exactly how they influence MS and by examining this information, we will be able to know more concretely the causes of the disease and thereby be closer to finding more effective treatments or possibly even a cure. Because multiple sclerosis affects so many people in America and we do not know the causes of it, it should be one the top research priorities for those in the field of medical research.


WWW Sources
(1)WebMDHealth, Multiple Sclerosis (MS): Topic Overview
(2) Wikipedia: Multiple Sclerosis
(3) WebMD Health News: Birth control pills may lower MS risk
(4)MedlinePlus: Oral contraceptives may cut multiple sclerosis risk
(5)MedlinePlus: Molecule governing myelin production found
(6)WebMD Health News: Sun exposure may reduce multiple sclerosis risk
(7)WebMD Health News: Sex hormones may affect multiple sclerosis
(8)WebMD Health News: Birth month tied to multiple sclerosis risk
(9)WedMD Health News: Multiple sclerosis tied to iron in brain
(10)WebMD Health News: Smoking tied to multiple sclerosis progression


Full Name:  Matt
Username:  mlowe@haverford.edu
Title:  Lowe
Date:  2005-09-26 10:44:26
Message Id:  16312
Paper Text:

<mytitle>

Biology
103

2005 First Paper
On href=/>Serendip

In this paper, I would like to begin a discussion of the development of western medicine, and science in general, with the epidemic of the bubonic plague marking a turning point. The social, cultural and intellectual role of medicine, which was not always considered a science, has undergone tremendous change, passing between the realms of philosophers to police to the battlefield to the church. Prior to the plague, its role was always somewhat more fluid, playing a lesser part in some civilizations than in others. For Western Europe, it took a massive medical catastrophe to spur the institutionalization of medicine as we almost universally conceive of it today.
In an examination of the social implications of the policies of compartmentalization and surveillance in combating the plague, Michel Foucault relays some methods of "disinfecting" and preventing transmission of disease during the plague. Quarantine in the home is imposed. Teams move through the city, building by building, hoisting objects off the floor, pouring perfume around the room, sealing all openings with wax, and setting the perfume on fire. The use of perfume speaks to the long-held notion that illness was spread by bad odors, but it is interesting that it was set alight (which, of course, likely did a good deal to kill the contagion - much more than the scent of the perfume, in any case.) While Foucault's language paints a grim picture of the mechanism of power into which this model of surveillance would develop, these practices and others instituted during this time marked a certain rigor of observation and attention to detail that would set a tone for scientific developments to come.
It was in part the serial nature of infestations of the plague that spurred reexamination of the causes of the plague. Female lepers and Jews were some of the first targets, accused of having corrupted society and incurred the wrath of God. The failure of this model led in the coming decades to the aforementioned increased government involvement in public life and emphasis on sanitation, as well as a debate between the classical-inherited idea of disease as divine retribution on one side and physical transmission on the other. Clearly there was to be some future in the latter concept.
The pandemic of the plague was an understandable eventuality in the context of the medical history of Western Europe which, until the renaissance and modern ages, lagged significantly behind that its neighbors in Greece and the middle east. The problem of living in contact with sewage and other pestilent materials was first dealt with not after the destruction of the plague, but well before. The Roman Empire in particular developed sophisticated sewer systems, and a practice of good hygiene similar to what we perform today was normatively enforced. The trade of the physician, however, was held in little esteem, and many famous doctors from the Roman Empire were originally brought as slaves from the Roman conquest of Greece. In time many were able to purchase their freedom, and the first real hospitals, equipped with plumbing and built to allow circulation of air (1). These developments failed to materialize in any significant way in the societies that were to flourish in the provinces of the former empire. We understand that the best of science is the explanation that best accounts for past observations. Was the correlation between good hygiene and good health lost in the shuffle during the fall of the empire? Or was Christian dogmatism powerful enough to obscure past advancements that were completely reasonable? It is possible that I am granting reason too great a role in the ideological formation of medieval Europe.
Around the turn of the millennium the significant work in medicine was done in the Arab world, drawing on the advancements in facilities of the Romans and the philosophical work of the Greeks. In the Christian world, by contrast, prior learning was obscured and healing power was attributed, among other objects of superstition, to religious relics. The theory of the humors prevailed in treatment of the sick, and practices of medicine and surgery were cleanly divided. In addition, the still-fragmented social structure of Western Europe fostered divides and non-communication of various developments. Constantly shifting Christian cults took up and disposed of the various bodies of knowledge developed during the classical age and the present time. Due in part to the inconsistent value placed on secular learning, hygiene in these countries remained something less than universal well after the plague, despite advances made in the field scattered over a wide area. Even royalty as late as the 17th century washed only once a year based on the notion, dating back to the expatriate Greek anatomist Galen in the 3rd century, that water could obstruct the pores. A parchment dated to 1145, likely from Hereford, England, points to Hippocratic theories and philosophies as a point of departure, suggesting an interest in relying on rational (non-religious/superstitious) explanations and treatments of disease.
It has been a bit of a challenge finding the line drawn between medicine as a philosophy and medicine as a science. Like the "school of thought" that a philosopher may have, famous physicians were known for their "schools." These were originally closer to renowned apprenticeships than institutions, with the first curriculum of medicine offered at the University of Bologna in the 13th century. In what scholarship I have found of the famous physicians from the ancient and medieval western world, there is an implication that the schools each held their particular, peculiar teaching as the true medicine. No school was innocent of holding certain unproven, untested superstitions as central tenets of theory and practice. What is certainly clear is that the definition of the body of "facts" was hotly contested among the different schools, even in areas as immediately verifiable as simple anatomy. The enormously influential anatomy by Galen inferred much from dissected pigs, which he called the "animal closest to man."
The debate demands the question: what is the difference between a philosophy and a science? It could be suggested that the difference is marked by the practice of empiricism, by experimentation and logic as opposed to superstition or metaphysics. However, as we have noted in class, logic is little more than a philosophy, and even the most respected, rigorous philosophies rely on assumptions that do or do not make sense according to the cultural context, which is informed in no small part by prevailing metaphysical history. It is our cult: may we really claim its Truth?
This argument loses some weight in light of the fact modern science and medicine have reduced extremely complex chemical and biological processes to tight mathematical formulas, which compute accurately all measurable ingredients and products. Can these developments actually be disputed? The basic tenets of modern medicine seem unshakeable, but this was likely also the attitude of these "philosophical physicians." What scientific, medical arrogances await disproof by other, future doctors? Is it possible that some aspects of our medicine have some undeniable element of Truth, and that these may remain while other (equally respected) practices are thrown out? The line of division in this discussion probably falls between medical science and treatment. We westerners know our chemicals, but recent years have shown us that even within the culture there is search for better treatment than the chemicals can offer. Eastern and holistic medicine, among others, are claiming devotees scientific-minded and right-brained alike. An interesting development here is that some of these practices and remedies are actually regarded as philosophies in their cultures of origin, rather than sciences. It calls into question our modern belief in science that lets us laugh at the naiveté of medicine during the plague, equally "unscientific" as the alternative remedies currently demonstrating themselves superior to our science. What modern superstitions, what secret plagues of our time stand to be eliminated by future wisdom?
1 http://pacs.unica.it/biblio/lesson2.htm

1)A history of Hellenistic, Roman, and Medieval medicine

2)Brown Italian Studies site

3)National Institute of Health site, Section on Medieval medical manuscripts

4)Middle Ages - Health, a website of general information on medieval life

5)Plague and Public Health in Renaissance Europe

6) Foucault, Michel. Discipline and Punish. New York: Vintage Books, 1977



Full Name:  Zachary Grunau
Username:  zgrunau@haverford.edu
Title:  Defining Life: The Virus
Date:  2005-09-26 10:45:43
Message Id:  16313
Paper Text:

<mytitle>

Biology
103

2005 First Paper
On href=/>Serendip

The definition of "life," it seems, must remain ambiguous. For the most part, life on earth is easily distinguished from non-life. A horse, for example, is alive, while a rock is not. As computer technology becomes more advanced and software more complex, the possibility of artificial intelligence grows—thus begging new questions concerning the nature of life. However, there is one kind of thing on the planet that straddles the boundaries of life already: the virus. A.I., as we can imagine, could be considered alive because of its staggering complexity and vast array of life like features. Viruses, while made up of organic material, are simple enough that they seem closer to the more complex organic molecules than complex forms of life. Allowing viruses the label, "life", changes many conceptions of "life." Examining closely the reasons why viruses are straddling the boundaries of many definitions of life can help us to understand exactly why life is so difficult to contain in one definition.
Viruses are essentially strands of DNA or RNA protected by a protein shell. They cannot reproduce on their own. Instead, viruses require cells of living beings to reproduce. This process involves the virus invading the host cell through a variety of means. The HIV virus, for example, attaches to receptors on the membrane of the cell and wait to be mistakenly absorbed. (1) Once inside the cell, the genetic material is released, which then makes the cell into a virus producing machine, abandoning its original function and using its resources to create as many viruses as possible before the cell dies. The new viruses then move on to repeat the process on other nearby cells. (2)
From this description of the viral reproduction process, we see that viruses have something that would strongly move its status towards "alive": genes. The RNA or DNA inside of a virus functions identically as in other life forms, controlling the production of proteins in cells. Thus, a virus recreates itself, though it requires another cell to do so. By many definitions, nothing alive requires complicated systems outside itself to reproduce, at least on a cellular level. Thinking on larger scales however, shows that most, if not all known forms of life, require other forms of life in order to survive. Many use other life forms in their reproductive process—many species of plants require that animals carry their seed to new places in order to best spread out. Flowers often use insects to pollinate—without the insects, pollination and therefore reproduction would be essentially impossible for them. Autonomous self-reproduction is a tricky term, seeing as reproduction is an enormously complicated process for so many forms of life, and using it as a characteristic of life is problematic in that it is so ambiguous.
Viruses are simple in construction—however, their interaction with more structurally complex organisms is anything but. While their process of reproduction is simple, viruses cause vastly different reactions in all the different forms of life they infect. The common cold, herpes, and HIV all are viruses that effect humans, but each works on different cells in different parts in the body to create vastly different symptoms in the host. Many viruses do not kill their host. Some, like herpes, can live in a host for an entire lifetime, feeding off of the cells but not killing the system. Some, like the common cold, are easily overtaken by a healthy immune system's antibodies. Others, like HIV, inevitably destroy their hosts, self-destructing along with them. These examples show the complicated cycles of viruses. It would be unconventional to say that a kind of rhythm is a characteristic of life, but surely many would agree that life does move in a rhythmic way.
Surely rocks do not behave similarly. Viruses have a relationship with life, for sure, in both their similarities in genetic/protein structures and in the fact that viruses require life. Giving up the requirement that things must autonomously self-reproduce in order to be alive eliminates most of the debate about calling viruses alive, and, so, for the purposes of this paper, we will do just that. So, now that we assume something like a virus is alive, we have a problem in front of us. What else, then can be considered alive in this framework? Surely a self-replicating nanotechnology is possible. Scientists already use viruses as tools in genetic study, carrying specific genes to cells. (2) Should we then consider these tools alive? The difference between them and the naturally occurring virus is insignificant.
Why is it that we feel uncomfortable calling our own creations "living"? That the virus arose from the natural world creates in us a sense that it should at least be considered half-living. However, very small self-replicating machines do not seem to fit comfortably in any of the standard definitions of life. Viruses are made up of organic material similar to what exists in our cells—if we build machines out of this material, could we then call it "alive"? We must, if we consider viruses to be alive. Still—as of now, all life has arisen out of the natural world, not out of human construction.
The debate concerning the status of viruses continues—and we have not answered any questions, only explored reasons why there is this problem of defining "life." This discussion does hint at an interesting trend—life seems to be composed of complicated interactions based in some kind of self-reproduction. The more we allow for simpler things to be alive and the less terms we ask of things in order to consider them alive, the more we have to consider wilder conceptions of what it means to be alive. Weather systems, planetary systems, even molecules all might some day fall under such a definition. Surely our own creations will someday be causing fierce debates. Already people fight over the imagined nature of A.I.—which, if "alive," will not necessarily reproduce nor will have an earthly body of the sort every other kind of life does.
Life must not be containable in any kind of principle or rule. Instead, it seems to be only containable in an idea of a community; in an idea of a specific kind of system and the parts of that system. With that kind of definition, we may be able to approach the future with a new and open mind for what we might find, alive, half-alive, machine, or otherwise.

(1) CellsAlive Homepage
(2) Wikipedia's Virus Page
(3) Wikipedia's Life Page
(4) Virology.net


Full Name:  Scott Sheppard
Username:  ssheppar@haverford.edu
Title:  Buprenorphine: The Drug Addicts Should have Seen Years Ago
Date:  2005-09-26 10:56:31
Message Id:  16314
Paper Text:

<mytitle>

Biology
103

2005 First Paper
On href=/>Serendip


It is an understated fact that Biology is inherently a social science rather than a distanced, objective study of living things. This becomes quite apparent in medicine when the preconceived distinction between social and natural blurs—the disease and the person with a disease are not extricable—and people inhibit the progress of healthcare by ignoring the categorical conflation. Over the past ten years, one can follow the frustratingly slow developments to increase availability of the revolutionary drug, Buprenorphine. The addicts may finally be throwing around the term Bupe, and in the heroin addiction department, slang can be one of the most important indicators of progress—a social assumption. As America continues to throw money into the "noble" and "moral" campaign that is the War on drugs, drugs continue to kick America's ass. It has taken years to finally bring bupe to the people and the reasons for this are countless, but one thing is certain: when a problem is not observed from every possible point of view the solutions that humans come up with will always re-enforce biases, and constantly miss the mark.

In 2002 Buprenorphine finally was approved by the FDA after ten plus years of testing and analysis. Bupe is described as a partial agonist for mu receptors in the brain(receptors that mediate analgesia (relief from pain) typically induced by opiates), which basically means that in some ways it works as a pure agonist opiate such as methadone and heroin, but in other ways it is unique. Buprenorphine does not give users a sense of feeling high, it merely relieves withdraw symptoms, and it binds with the mu receptors for longer durations, keeping recovering heroin addicts stable and comfortable for up to 48 hours. Buprenorphine also can act as an antagonist when used at higher dosages which means that after a certain quantity, bupe will actually create withdraw symptoms such as nausea, sweating, and other flu-like symptoms. This effect makes it difficult to misuse bupe—an attractive quality for users who find themselves abusing methadone in their attempt to stay off heroin. Bupe's antagonist characteristics also make it difficult to get high with additional opiates, so even if an addict were to shoot up within two days of taking bupe, he would regret the nauseating experiment. Additionally, bupe is not nearly as addictive as methadone or heroin, giving heroin addicts the opportunity to effectively lower their tolerance to opiates and wean themselves entirely from a dependence on narcotics. 2.

All of these very attractive qualities might invite skepticism; it seems as though bupe is a dream drug that would have hit the streets with a bang. This drug has been tested next to methadone for the last ten years, and the results are mixed although methadone remains to be perceived as the more effective treatment overall. In most tests effectiveness is gauged by two factors: patient retention and suppression of heroin use. Heroin addicts are able to more likely to stay off of heroin for longer periods of time with high doses of methadone, and more patients stick with their methadone treatment plans than bupe treatment plans. What has been underestimated in these scientific studies is how different types of users require different types of treatment. It may be that bupe is more effective for the strong-willed user who wants to free himself from all opiates, but needs a way of alleviating the severe withdraw symptoms. Methadone is a stronger narcotic, it gives users a buzz, and as long as it is in strong supply, many recovering heroin users would be perfectly content trading their heroin addiction for a less incapacitating methadone addiction; this is not meant to be passive aggressive raillery that discreetly de-legitimates methadone, but this is how many people feel when they use methadone. Bupe gives addicts another option in dealing with their dependence.

Unlike methadone bupe can be distributed by primary care physicians rather than clinics, and because it is so difficult to abuse, users are freed from the social stigmas that daily visits to the methadone clinics incur. The conservative promotion of bupe along with its ambivalent status as a less potent, less effective but promising alternative to methadone has made it difficult for heroin addicts to realize bupe's potential. In Europe countries such as France use bupe more than methadone and the results seem to be positive. Sources claim "a drop of 80% in opiate overdoses in France as well as a four-fold drop in HIV reports since 1995. In addition, drug related crime has dropped by a factor of 3." 1. These studies claimed to be recent as of April, 2002. France has done other tests showing that methadone may still more effective in preventing recovering addicts but it admits that the social reality makes buprenorphine very attractive, because it is disseminated by general practitioners as a regular prescription drug would be.

In America bupe is finally exiting a gauntlet of bureaucratic regulations and close-mindedness. Even when an amendment to the Harrison Act (an act that carefully governs doctor's ability to prescribe opiates) was made in 2000 to allow prescriptions of bupe to be filled, the amendment was far from flawless. Initially this amendment prohibited methadone clinics from providing bupe, and although this prohibition was dropped a year later, it added to the unspoken sentiment that addicts did not need options, they needed methadone. The amendment gave private practices the right to prescribe it, but social apprehension and lack of motivation have quelled the initial revolutionary status that bupe entailed. Sources claim that "In New York City an estimated 200,000 heroin addicts and perhaps two to three times that many prescription opiate addicts, some 34,000 people were on methadone maintenance throughout 2004, while only about 1,000 people filled a bupe prescription." (7)

This amendment also screwed the pooch in defining its terms. It allowed "single providers" to fill only thirty bupe prescriptions at a time, and the category "single provider" ranged from single physician practices to huge HMO's and hospitals. An organization could include over fifty doctors, and it would still be limited to thirty bupe prescriptions. This restriction was just lifted in August 2005 so that now the ratio is more pragmatically determined by the number of doctors—for every doctor thirty prescriptions may be filled. 5. More and more people are beginning to realize that bupe works and it offers something different to heroin addicts who thought methadone was the only way out.

Bupe's frustrating progress can be explained in terms of its poorly regulated availability, questionable effectiveness, and practitioner apathy, but these stumbling blocks are actually symptoms of larger ideological problems. Heroin addiction is a problem that affects the quality of life throughout the entire country, for users and non-users alike. HIV, crime, unemployment, and the state of the economy are just a few things on a long list that are very closely related to heroin addiction. Bupe's social appeal has been neglected because of two shortsighted opinions about heroin addiction in this country: the first is that heroin users are basically irrecoverable social losses and the other, is that heroin addiction is merely a medical affliction that should be treated strictly by the drugs with the best records. Heroin addiction is a disease, but diseases are inextricable from social structures and perceptions. Heroin addicts undeniably have a certain perception of themselves whether they are being treated at methadone clinics, mainlining for the first time, or hiding their dope behind a white collar job. Bupe has made such slow progress because its social benefits have been underestimated, and addicts should be able to treat their disease in the most appropriate ways.


International Treatment Center for Advancement of Addiction
The Medical Letter: Bupronorphine: An Alternative to Methadone
The Bupronephrine FAQ
Join Together
Common Sense for Drug Policy
Medicine Australia
Full Name:  Sara Koff
Username:  skoff@brynmawr.edu
Title:  Hunter's Struggle: The Story of Neimann Pick's Disease
Date:  2005-09-26 21:42:22
Message Id:  16323
Paper Text:

<mytitle>

Biology
103

2005 First Paper
On href=/>Serendip


In my sixth grade science class I sat next to a girl named Hunter Ozmer. Being that "K" and "O" are close in the alphabet we ended up sitting near each other in history class and we had lockers near one another. Hunter and I became fast friends. She seemed to be the average 12-year-old girl; we talked about make-up and boys and our favorite band NSYNC. The first time I went over the Hunter's house her mother took me aside and told me that Hunter had a disease called Niemann-Picks and that she was very different from me. At that time I had no idea what she was talking about or how this would come to affect my friendship with Hunter.
The official definition of Niemann-Pick's disease is "a group of inherited metabolic disorders known as the leukodystrophies or lipid storage diseases in which harmful quantities of a fatty substance (lipids) accumulate in the spleen, liver, lungs, bone marrow, and the brain" (1). What this meant for Hunter is that she would eventually loose of muscle coordination, her brain would begin to deteriorate, and very quickly Hunter and I would no longer function at the same level.
This rare disease is categorized in four types, the most common type being Type A. Type A Niemann- Pick occurs in infants and its symptoms include jaundice, an enlarged liver, and profound brain damage. Children who suffer with this type of Niemann-Pick seldom live past the age of 18 months. An enlarged liver also characterizes Type B but there is no brain damage associated with this type. Symptoms of Type B Niemann-Pick do not typically arise until adolescence. Both types A and B are caused by "insufficient activity of an enzyme called sphingomyelinase" which leads to the build up of toxic proportions of "sphingomyelin, a fatty substance present in every cell of the body" (2)
Hunter suffers from Type C Niemann-Pick, a fraction of this disease that is so rare there are only 500 reported cases worldwide. Type C is very different from Type A and B at the biochemical and genetic level. People afflicted with Type C are unable to "metabolize cholesterol and other lipids properly within the cell" (1). Therefore causing pockets of cholesterol and other lipids to accumulate in the liver, spleen and the brain.
Each person suffering from Type C differs in symptoms experienced, when the symptoms began and the progression of the disease. Hunter's first symptoms appeared around the age of six but did not start progressing rapidly until she reached puberty. In some cases symptoms can appear as early as a few months old or as late as adulthood. "Vertical gaze palsy (the inability to move the eyes up and down), enlarged liver, enlarged spleen, or jaundice in young children" (2) are strong indications of Niemann-Pick Type C. Most times only one or two symptoms occur at the onset of the disease. (2)
In most cases, neurological symptoms begin appearing between the ages of 4 and 10. Generally, the later neurological symptoms begin, the slower the progression of the disease. Type C is always fatal. The vast majority of children die before age 20 (and many die before the age of 10). Late onset of symptoms can lead to longer life spans but it is extremely rare for any person to reach 40. (1)
Hunter and I continued through junior high and high school together. She slowly began to regress and is now at the level of about a two-year-old child. Her first notable symptoms included difficulty swallowing and her speech became very slurred. In the eighth grade Hunter was moved from regular classes to special ed. because she was no longer able to keep up with her peers. By our junior year in high school Hunter served as a helper for the mentally challenged students because while all of us were rapidly learning new things Hunter's brain could not function well enough for her to retain and comprehend new information. She sat with us everyday at lunch and her mom had to pack her soft foods because it was getting continuously harder for Hunter to swallow; she was even on a feeding tube for a few months when she kept choking on her food. At the same time Hunter's motor skills also began to deteriorate and the last time I saw her she was using a walker. Even though her body is self destructing Hunter remains positive and is an inspiration to all of us.
Science has led researchers to believe that the metabolic processes disrupted by Niemann-Pick Type C are very simple but crucial. "While most metabolic processes differ among various species (reptiles, fish, and mammals all function very differently), forms of NPC have been identified in many species, including humans, cats, mice, worms, and yeast" (2). These metabolic processes are in fact one of the basic foundations for life. (2)
"In addition to being common among species, the metabolic process appears throughout an individual but is expressed in different ways" (2). The effects of these processes seem to also differ based on the organ. The effect on the spleen is different than the effect on the brain or central nervous system.
Since this disease is caused by a small number of genetic mutations this leads researchers to believe that even the smallest genetic disruption can have a huge effect on the organism. "Genes mutate frequently, but most mutations have no effect - they are either harmless (like an unusual eye color) or are offset by other genes performing similar tasks correctly". However with Niemann-Pick "any mutation is more likely to disrupt an important process. (2)
This disease has contributed to science as a whole because of the research done scientists have now discovered how cholesterol enters the cell and how it becomes a useful part of an organisms functions. The have also learned "how it is broken down by lysosomes, and how it is processed by the endoplasmic reticulum". Unfortunately, they are still unable to identify how cholesterol moves between parts of the cells which is believe to be the process affected directly by Niemann-Pick(2).
There is no cure for Neimann-Pick Type C. Hunter is on a medication developed in Tucson that has been shown to slow the progression of the disease in mice, but even this treatment is only in the research stages. (1)

1) http://www.ninds.nih.gov/disorders/niemann/niemann.htm
2) http://www.nnpdf.org/



Full Name:  Iris Mejia
Username:  imejia@haverford.edu
Title:  Understanding HPV
Date:  2005-09-26 23:41:42
Message Id:  16327
Paper Text:

<mytitle>

Biology
103

2005 First Paper
On href=/>Serendip

The process of discovering viruses begun in 1883 with Adolf Mayer, who sought the cause of a particular disease but was left without an explanation (1). His observations were limited to the existing technology, therefore he could only hypothesize that miniscule bacteria caused the disease. This hypothesis was proven incorrect in 1935 by Wendell Stanley, who did further study on the same disease (2). The disease was caused by a virus, which previously could not be seen. A virus is an infective agent that contains a protein coat surrounding RNA or DNA that can only reproduce within a host cell (3). Once this discovery was made many diseases with unknown causes were thought to be affected by viruses such as MS and cancer. This assumption limited the search for their respective cures. MS was found to be a neurological disease but 15% of human cancers worldwide, like cervical cancer, are still linked to viruses (4). The virus that causes the carcinogenic progression in cervical cancer is the Human Papilloma Virus, which I will explore to discover how it affects men and women differently.

The Human Papilloma Virus is a papovavirus, which consists of double stranded DNA and is transmitted sexually. It comes in hundreds of forms that affect the body in numerous ways. Current observations show that some strands of the virus can cause warts, while others remain latent in an individual for long periods of time without any noticeable differences in the vaginal/penal area but some of the latter can cause cervical changes that lead to cancer. Studies have shown that 90% of cervical cancers are due to HPV infection (5). HPV can infect males and females but only lead to cancer in women. Cervical cancer is the second leading cause of cancer deaths in women worldwide (6). College aged women have the highest prevalence of HPV ranging from 10-40% (7) so it is important to question why many college women have not heard of this disease or are misinformed. An explanation can be sought by looking at media coverage. Even though there has been a lot of research done in HPV, 50% of HPV stories are missing important information, such as not stating that condoms are imperfect at blocking this infection (8).

HPV research shows that there are many factors that can change the risk of acquiring an HPV infection but the greatest is sexual behavior. A study conducted between 1990 and 1997 with 444 women with undetectable HPV stated that "more than one third of sexually experienced young women who are not infected with HPV become infected during a 2 year period (9)." This is more than a 33% likelihood of HPV infection. The study showed that smoking increases the risk of HPV infection whereas condom use did not significantly reduce the risk of infection. The significance of the latter is that there may not be any method to reduce the risk of being infected with HPV except abstinence. If women are sexually active how can they protect themselves from this? In order to reduce their risk, women can limit their number of sexual partners and the frequency of intercourse, have regular pap smears and good hygiene, and stop smoking (10). The study mentioned earlier in the paragraph, concluded that women can lower their risk of HPV infection by increasing the length of time they know their partner before initial intercourse. Is there a problem with this way of lowering risk? HPV is nearly undetectable in men so even given time to get to know their partner women would be unaware of the risk of acquiring HPV from their partner. This leads to what men can do to lower their risk for acquiring and transmitting HPV.

Although, HPV seems to affect women more dramatically then men it is still a reality in men's health. Men can unknowingly be carriers of a virus that can change women's life drastically; therefore, he has as much power and responsibility as women to decrease the spread of HPV. What can men do to protect themselves? Based on a study group conducted between 1985 and 1993 of 1,913 men, circumcision may lower the risk of transmitting and acquiring HPV by 60% but will not protect from infection (11). Uncircumcised men have a higher chance of acquiring an STD than circumcised men (12). The foreskin, which is found in uncircumcised men, is a flap of skin that covers the penis. It can be an entryway for many diseases including HPV. This is not a recommendation to men to opt for circumcision, but a fact that needs to be pointed out so that men can understand their risks. Men can decrease their risks and protect themselves from HPV by limiting the number of sexual partners and knowing their partners' current health. Since HPV is detectable in women, a man can request his partner to perform a pap smear, which is usually the first step to discovering HPV.

HPV testing is done after abnormal cells have been found during a pap smear in a woman's vagina or cervix. Further testing, includes a colposcopy and possibly an HPV DNA test. HPV results are grouped into mild, moderate or severe depending on the lesions on the cervix. Moderate and severe lesions are at really high risk of developing to cervical cancer. Currently there is no suggested way of preventing or treating HPV for neither men nor women, but men treated for clinical studies have resulted in no change in a woman's recurrence of HPV. Women with moderate to severe lesions can be treated by a variety of methods such as lasers, but it all depends on each individual case.

The way HPV affects individuals may be an important reason why there is not more emphasis on cure and prevention. It can dramatically affect women's lives while posing minimal treat to men. How many people does a disease need to affect to receive attention?


References

1) Campell, Neal. Biology. California: Benjamin Cummings, 2002.
2) Campell, Neal. Biology. California: Benjamin Cummings, 2002.
3)Merriam Webster Online Dictionary, Dictionary home page.
4) Campell, Neal. Biology. California: Benjamin Cummings, 2002.
5) Lowy, Douglas. Genital Human Papilloma Virus; Proceddings of the National Academy of Sciences of The United States of America, Vol. 91, No. 7.
6)Center for Disease Control, HPV information.
7) London, S. Acquiring New Partner is Linked to Increased HPV Risk among Young Women; Perspectives on Sexual and Reproductive Health, Vol. 35, No. 3.
8)WebMD, HPV Information.
9) London, S. Acquiring New Partner is Linked to Increased HPV Risk among Young Women; Perspectives on Sexual and Reproductive Health, Vol. 35, No. 3.
10) Hollander, D. Human Papilloma virus Infection, Benign Lesions have different Risk Factors; Family Planning Perspectives, Vol. 33, No. 6.
11) Lowy, Douglas. Genital Human Papilloma Virus; Proceddings of the National Academy of Sciences of The United States of America, Vol. 91, No. 7.
12)WebMD, HPV Information.



Full Name:  Keti Shea
Username:  kshea@brynmawr.edu
Title:  Multiple Sclerosis: Autoimmunty and Genetics
Date:  2005-09-29 18:37:48
Message Id:  16382
Paper Text:

<mytitle>

Biology
103

2005 First Paper
On href=/>Serendip



This paper is an exploration into the complexities of autoimmune disorders, in particular those related to multiple sclerosis. An additional focus is on the interplay between external factors such as one's environment and genetics in order to better understand the concept of auto-immunity. These questions lead us to a further question of the role of science and in what ways does science help in making new discoveries? Given that there is no known cause or cure for MS, in what ways, if any, is science adequate in understanding the complexity of autoimmunity?

MS is a well-documented disease, affecting around 300,000 Americans and is second only to head trauma as the most common neurological cause of disability among young adults (4). Symptoms of the disease vary widely but they generally include numbness of the limbs, fatigue, double vision and/or loss of vision, imbalance, incoordination, speech problems, loss of motor control and chronic pain (4). These symptoms can be chronic as is the case with MS victims of the progressive type or they can be intermittent as in those patients with relapse-remitting MS (4). The fact that these symptoms vary drastically, among individuals but also within the individual course of the disease, is one of the reasons that MS is so hard to treat. There is drug treatment but patients often respond
differently, or not at all, and severe side effects may result (7).

While the symptoms of the disease vary, the population it attacks does not: the majority of MS sufferers are women of Northern European heritage (7). There is an extremely low prevalence of MS in populations of African blacks, Asians and ethnic groups with little Caucasian mixing.This is where the field of genetic becomes crucial; by researching and comparing chromosomal sites of MS victims and their families, these studies seek to address the question of why MS is so prevalent among Caucasian women between the ages of 20 and 50 (7).

In order to understand genetic studies involving MS, one has to first understand how the disease itself functions. MS is characterized by lesions on the brain, inflammations which occur due to demyelination. Myelin is a combination of lipid fats (80%) and proteins (20%) which sheath the axons, or nerve cells, in the central nervous system (7). Myelin affects the speed with which nerve signals (impulses) can move down the axons. In MS, this myelin is destroyed and can no longer act as an axon sheath, inhibiting the transmission of nerve signals and also leading to partial or total nerve damage . Myelin is destroyed by T-cells which recognize myelin as a foreign body and therefore destroy it; it is this process in which the body actively attacks its own cells which led to the designation of MS as an autoimmune disorder (7).

Genetic research is essential to understanding MS. It is a complex disorder, meaning that it is multifactorial and polygenic: it does not strictly follow Mendelian patterns of inheritance because there are multiple, interacting genes involved (3). This is complicated by the belief that each gene contributes relatively little to overall risk of susceptibility; it is only in the specific way in which these genes interact with one another and with the environment which triggers the onset of MS (3). Scientists have, however, been able to locate eight regions of interest at chromosomes 5, 6, 17 and 19. The regions are singled out as showing linkage to MS and were derived from family-based association studies which examine which alleles are transmitted to children through a test called the transmission-disequilibrium test (2). The interaction of multiple genes is further complicated by the fact that primary genetic heterogeneity can occur in those affected by MS, meaning that different genes can cause similar and even identical forms of MS (2).

Another interesting way in which genes are important to MS research lies in the differentiation between susceptibility genes and modifier genes. For example, the HLA-DR2 haplotype at chromosome 6 has shown linkage to MS because of the way HLA alleles (a DNA coding of a single gene), respond to antigens (proteins) (2). These genes may not only influence susceptibility but also clinical symptoms such as how the disease develops and progresses and how patients respond to drug therapies. For instance, studies have shown that there is an association between the apolipoprotein-4 allele and the severe MS strains . Similarly, those patients in this group study who suffered from mild strains of MS contained a larger percentage of the APOE-2 allele carriers (2). This means that a carrier of a certain allele may experience symptoms differently than someone who
carries a different allele.

Additionally, past studies conducted on twins shows a linkage between genetic make-up and disease susceptibility. For example, the rate of susceptibility of the general population is 0.1% while for siblings and fraternal twins it is about 5% . But while there is an increased susceptibility for those related to MS victims, genetics is not the exclusive factor. If that were so, there would be a concordance rate of nearly 100% for identical twins. This is not the case. This suggests then that genetics may contribute to susceptibility but there are other environmental (and unknown) factors which trigger the onset of the disease. This trigger is as yet
unknown but is believed to be a virus or bacteria of some sort. The Multiple Sclerosis Genetics Group puts it thus, "...it is also likely that interactions with infectious, nutritional, climatic,and/or other environmental influences affect susceptibility considerably. This complex array of factors results in a severe disregulation of the immune response, loss of immune homeostasis and self-tolerance..."
(7). In other words, while scientists have been able to identify linkage in certain chromosomal regions, the complex interplay of factors which affect such things as age at disease onset, intensity and duration of symptoms and reaction to drug therapy, combine in such a way to make MS unpredictable.

An additional point of interest that this citation brings forth is the idea of "self-tolerance" or auto-immunity. How exactly does one respond or deal with instances when the body actually turns on itself? This is the question which science now has to try to answer. There is treatment for MS but there is no cure or any known cause. This leads us to the question of the role of science and more specifically, are there some questions which science simply cannot answer?

As one Biology student comments in her paper "MS and the Self": "People guard their mental functioning closely. However, when the cognitive problems of MS set in, they may find that they have lost hold of that which they consider to encompass "self" (1). Her point is a good one in that it comments on the psychological implications of this disease which is at once mentally and physically debilitating. It is also profoundly debilitating psychologically due to its inherent unpredictability. The occurrence of MS and other autoimmune disorders directs our focus to the workings of the human body, those biological processes which (healthy) humans take for granted. It is these processes which we are unaware of; like breathing and winking, the body performs numerous and intricate tasks without us even realizing. But what happens when the possibility of malfunction, of human error in a quite literal sense of the expression, takes place? This is the most debilitating realization that can be drawn:
the realization that one's body and its mechanics are faulty, that what is "alien" and what is "self" are not distinguished by the brain. Here is a breakdown of communication at the most basic level- not between individuals, but within them, at the cellular level. And all this is beyond one's control.

In conclusion, some comments were made in the course forum area which described science as useful despite its weaknesses. We can debate its truthfulness or its accuracy but its utility as a way to describe and understand how and why things happen remains essential (5). This is true even in the case of MS. There may be gaps in scientific knowledge but this is not to say that science loses its value as an exploratory tool. Studies in MS have shown how scientific research leads to new questions which lead to further research. Although many questions concerning MS remain unanswered, these unanswered questions lead to further explorations in the field of autoimmunity.

Sources:
1)Multiple
Sclerosis and the Self
, can be found on Serendip website.

2) Multiple
Sclerosis as Genetic Disease
.

3)Genetics and
Multiple Sclerosis
.

4)Multiple Sclerosis: The Immune System's TerribleMistake.

5)Biology 103 Forum area, on the Biology 103 website.

6)
Genetics- The Basic Facts
, on the National MS Society website.

7)
Research Directions in Multiple Sclerosis
, on the National MS Society website.



Full Name:  Matthew Lowe
Username:  mlowe@haverford.edu
Title:  The Plague and Development of Modern Medicine
Date:  2005-10-04 19:19:02
Message Id:  16444
Paper Text:
<mytitle> Biology 103
2005 First Paper
On Serendip

In this paper, I would like to begin a discussion of the development of western medicine, and science in general, with the epidemic of the bubonic plague marking a turning point. The social, cultural and intellectual role of medicine, which was not always considered a science, has undergone tremendous change, passing between the realms of philosophers to police to the battlefield to the church. Prior to the plague, its role was always somewhat more fluid, playing a lesser part in some civilizations than in others. For Western Europe, it took a massive medical catastrophe to spur the institutionalization of medicine as we almost universally conceive of it today.

In an examination of the social implications of the policies of compartmentalization and surveillance in combating the plague, Michel Foucault relays some methods of "disinfecting" and preventing transmission of disease during the plague. Quarantine in the home is imposed. Teams move through the city, building by building, hoisting objects off the floor, pouring perfume around the room, sealing all openings with wax, and setting the perfume on fire. The use of perfume speaks to the long-held notion that illness was spread by bad odors, but it is interesting that it was set alight (which, of course, likely did a good deal to kill the contagion - much more than the scent of the perfume, in any case.) While Foucault's language paints a grim picture of the mechanism of power into which this model of surveillance would develop, these practices and others instituted during this time marked a certain rigor of observation and attention to detail that would set a tone for scientific developments to come.

It was in part the serial nature of infestations of the plague that spurred reexamination of the causes of the plague. Female lepers and Jews were some of the first targets, accused of having corrupted society and incurred the wrath of God. The failure of this model led in the coming decades to the aforementioned increased government involvement in public life and emphasis on sanitation, as well as a debate between the classical-inherited idea of disease as divine retribution on one side and physical transmission on the other. Clearly there was to be some future in the latter concept.

The pandemic of the plague was an understandable eventuality in the context of the medical history of Western Europe which, until the renaissance and modern ages, lagged significantly behind that its neighbors in Greece and the middle east. The problem of living in contact with sewage and other pestilent materials was first dealt with not after the destruction of the plague, but well before. The Roman Empire in particular developed sophisticated sewer systems, and a practice of good hygiene similar to what we perform today was normatively enforced. The trade of the physician, however, was held in little esteem, and many famous doctors from the Roman Empire were originally brought as slaves from the Roman conquest of Greece. In time many were able to purchase their freedom, and the first real hospitals, equipped with plumbing and built to allow circulation of air (1). These developments failed to materialize in any significant way in the societies that were to flourish in the provinces of the former empire. We understand that the best of science is the explanation that best accounts for past observations. Was the correlation between good hygiene and good health lost in the shuffle during the fall of the empire? Or was Christian dogmatism powerful enough to obscure past advancements that were completely reasonable? It is possible that I am granting reason too great a role in the ideological formation of medieval Europe.

Around the turn of the millennium the significant work in medicine was done in the Arab world, drawing on the advancements in facilities of the Romans and the philosophical work of the Greeks. In the Christian world, by contrast, prior learning was obscured and healing power was attributed, among other objects of superstition, to religious relics. The theory of the humors prevailed in treatment of the sick, and practices of medicine and surgery were cleanly divided. In addition, the still-fragmented social structure of Western Europe fostered divides and non-communication of various developments. Constantly shifting Christian cults took up and disposed of the various bodies of knowledge developed during the classical age and the present time. Due in part to the inconsistent value placed on secular learning, hygiene in these countries remained something less than universal well after the plague, despite advances made in the field scattered over a wide area. Even royalty as late as the 17th century washed only once a year based on the notion, dating back to the expatriate Greek anatomist Galen in the 3rd century, that water could obstruct the pores. A parchment dated to 1145, likely from Hereford, England, points to Hippocratic theories and philosophies as a point of departure, suggesting an interest in relying on rational (non-religious/superstitious) explanations and treatments of disease.

It has been a bit of a challenge finding the line drawn between medicine as a philosophy and medicine as a science. Like the "school of thought" that a philosopher may have, famous physicians were known for their "schools." These were originally closer to renowned apprenticeships than institutions, with the first curriculum of medicine offered at the University of Bologna in the 13th century. In what scholarship I have found of the famous physicians from the ancient and medieval western world, there is an implication that the schools each held their particular, peculiar teaching as the true medicine. No school was innocent of holding certain unproven, untested superstitions as central tenets of theory and practice. What is certainly clear is that the definition of the body of "facts" was hotly contested among the different schools, even in areas as immediately verifiable as simple anatomy. The enormously influential anatomy by Galen inferred much from dissected pigs, which he called the "animal closest to man." The debate demands the question: what is the difference between a philosophy and a science? It could be suggested that the difference is marked by the practice of empiricism, by experimentation and logic as opposed to superstition or metaphysics. However, as we have noted in class, logic is little more than a philosophy, and even the most respected, rigorous philosophies rely on assumptions that do or do not make sense according to the cultural context, which is informed in no small part by prevailing metaphysical history. It is our cult: may we really claim its Truth?

This argument loses some weight in light of the fact modern science and medicine have reduced extremely complex chemical and biological processes to tight mathematical formulas, which compute accurately all measurable ingredients and products. Can these developments actually be disputed? The basic tenets of modern medicine seem unshakeable, but this was likely also the attitude of these "philosophical physicians." What scientific, medical arrogances await disproof by other, future doctors? Is it possible that some aspects of our medicine have some undeniable element of Truth, and that these may remain while other (equally respected) practices are thrown out? The line of division in this discussion probably falls between medical science and treatment. We westerners know our chemicals, but recent years have shown us that even within the culture there is search for better treatment than the chemicals can offer. Eastern and holistic medicine, among others, are claiming devotees scientific-minded and right-brained alike. An interesting development here is that some of these practices and remedies are actually regarded as philosophies in their cultures of origin, rather than sciences. It calls into question our modern belief in science that lets us laugh at the naiveté of medicine during the plague, equally "unscientific" as the alternative remedies currently demonstrating themselves superior to our science. What modern superstitions, what secret plagues of our time stand to be eliminated by future wisdom?

Bibliography

1)A history of Hellenistic, Roman, and Medieval medicine

2)Brown Italian Studies site

3)National Institute of Health site, Section on Medieval medical manuscripts

4)Middle Ages - Health, a website of general information on medieval life

5)Plague and Public Health in Renaissance Europe

6) Foucault, Michel. Discipline and Punish. New York: Vintage Books, 1977




Full Name:  Sara Koff
Username:  skoff@brynmawr.edu
Title:  Hunter's Struggle: The Story of Niemann Pick's Disease
Date:  2005-10-05 10:41:16
Message Id:  16450
Paper Text:

<mytitle>

Biology
103

2005 First Paper
On href=/>Serendip

In my sixth grade science class I sat next to a girl named Hunter Ozmer. Being that "K" and "O" are close in the alphabet we ended up sitting near each other in history class and we had lockers near one another. Hunter and I became fast friends. She seemed to be the average 12-year-old girl; we talked about make-up and boys and our favorite band NSYNC. The first time I went over the Hunter's house her mother took me aside and told me that Hunter had a disease called Niemann-Picks and that she was very different from me. At that time I had no idea what she was talking about or how this would come to affect my friendship with Hunter.




The official definition of Niemann-Pick's disease is "a group of inherited metabolic disorders known as the leukodystrophies or lipid storage diseases in which harmful quantities of a fatty substance (lipids) accumulate in the spleen, liver, lungs, bone marrow, and the brain" (1). What this meant for Hunter is that she would eventually loose of muscle coordination, her brain would begin to deteriorate, and very quickly Hunter and I would no longer function at the same level.




This rare disease is categorized in four types, the most common type being Type A. Type A Niemann- Pick occurs in infants and its symptoms include jaundice, an enlarged liver, and profound brain damage. Children who suffer with this type of Niemann-Pick seldom live past the age of 18 months. An enlarged liver also characterizes Type B but there is no brain damage associated with this type. Symptoms of Type B Niemann-Pick do not typically arise until adolescence. Both types A and B are caused by "insufficient activity of an enzyme called sphingomyelinase" which leads to the build up of toxic proportions of "sphingomyelin, a fatty substance present in every cell of the body" (2)




Hunter suffers from Type C Niemann-Pick, a fraction of this disease that is so rare there are only 500 reported cases worldwide. Type C is very different from Type A and B at the biochemical and genetic level. People afflicted with Type C are unable to "metabolize cholesterol and other lipids properly within the cell" (1). Therefore causing pockets of cholesterol and other lipids to accumulate in the liver, spleen and the brain.
Each person suffering from Type C differs in symptoms experienced, when the symptoms began and the progression of the disease. Hunter's first symptoms appeared around the age of six but did not start progressing rapidly until she reached puberty. In some cases symptoms can appear as early as a few months old or as late as adulthood. "Vertical gaze palsy (the inability to move the eyes up and down), enlarged liver, enlarged spleen, or jaundice in young children" (2) are strong indications of Niemann-Pick Type C. Most times only one or two symptoms occur at the onset of the disease. (2)
In most cases, neurological symptoms begin appearing between the ages of 4 and 10. Generally, the later neurological symptoms begin, the slower the progression of the disease. Type C is always fatal. The vast majority of children die before age 20 (and many die before the age of 10). Late onset of symptoms can lead to longer life spans but it is extremely rare for any person to reach 40. (1)




Hunter and I continued through junior high and high school together. She slowly began to regress and is now at the level of about a two-year-old child. Her first notable symptoms included difficulty swallowing and her speech became very slurred. In the eighth grade Hunter was moved from regular classes to special ed. because she was no longer able to keep up with her peers. By our junior year in high school Hunter served as a helper for the mentally challenged students because while all of us were rapidly learning new things Hunter's brain could not function well enough for her to retain and comprehend new information. She sat with us everyday at lunch and her mom had to pack her soft foods because it was getting continuously harder for Hunter to swallow; she was even on a feeding tube for a few months when she kept choking on her food. At the same time Hunter's motor skills also began to deteriorate and the last time I saw her she was using a walker. Even though her body is self destructing Hunter remains positive and is an inspiration to all of us.




Science has led researchers to believe that the metabolic processes disrupted by Niemann-Pick Type C are very simple but crucial. "While most metabolic processes differ among various species (reptiles, fish, and mammals all function very differently), forms of NPC have been identified in many species, including humans, cats, mice, worms, and yeast" (2). These metabolic processes are in fact one of the basic foundations for life. (2) "In addition to being common among species, the metabolic process appears throughout an individual but is expressed in different ways" (2). The effects of these processes seem to also differ based on the organ. The effect on the spleen is different than the effect on the brain or central nervous system.




Since this disease is caused by a small number of genetic mutations this leads researchers to believe that even the smallest genetic disruption can have a huge effect on the organism. "Genes mutate frequently, but most mutations have no effect - they are either harmless (like an unusual eye color) or are offset by other genes performing similar tasks correctly". However with Niemann-Pick "any mutation is more likely to disrupt an important process. (2)




This disease has contributed to science as a whole because of the research done scientists have now discovered how cholesterol enters the cell and how it becomes a useful part of an organisms functions. The have also learned "how it is broken down by lysosomes, and how it is processed by the endoplasmic reticulum". Unfortunately, they are still unable to identify how cholesterol moves between parts of the cells which is believe to be the process affected directly by Niemann-Pick(2).




There is no cure for Neimann-Pick Type C. Hunter is on a medication developed in Tucson that has been shown to slow the progression of the disease in mice, but even this treatment is only in the research stages. (1)




1) http://www.ninds.nih.gov/disorders/niemann/niemann.htm


2) http://www.nnpdf.org/



Full Name:  Zachary Grunau
Username:  zgrunau@haverford.edu
Title:  Defining Life: The Virus
Date:  2005-10-06 11:56:44
Message Id:  16483
Paper Text:
<mytitle> Biology 103
2005 First Paper
On Serendip

Defining Life: The Virus Zachary Grunau September 26, 2005

The definition of "life," it seems, must remain ambiguous. For the most part, life on earth is easily distinguished from non-life. A horse, for example, is alive, while a rock is not. As computer technology becomes more advanced and software more complex, the possibility of artificial intelligence grows—thus begging new questions concerning the nature of life. However, there is one kind of thing on the planet that straddles the boundaries of life already: the virus. A.I., as we can imagine, could be considered alive because of its staggering complexity and vast array of life like features. Viruses, while made up of organic material, are simple enough that they seem closer to the more complex organic molecules than complex forms of life. Allowing viruses the label, "life", changes many conceptions of "life." Examining closely the reasons why viruses are straddling the boundaries of many definitions of life can help us to understand exactly why life is so difficult to contain in one definition.

Viruses are essentially strands of DNA or RNA protected by a protein shell. They cannot reproduce on their own. Instead, viruses require cells of living beings to reproduce. This process involves the virus invading the host cell through a variety of means. The HIV virus, for example, attaches to receptors on the membrane of the cell and wait to be mistakenly absorbed. (1) Once inside the cell, the genetic material is released, which then makes the cell into a virus producing machine, abandoning its original function and using its resources to create as many viruses as possible before the cell dies. The new viruses then move on to repeat the process on other nearby cells. (2)

From this description of the viral reproduction process, we see that viruses have something that would strongly move its status towards "alive": genes. The RNA or DNA inside of a virus functions identically as in other life forms, controlling the production of proteins in cells. Thus, a virus recreates itself, though it requires another cell to do so. By many definitions, nothing alive requires complicated systems outside itself to reproduce, at least on a cellular level. Thinking on larger scales however, shows that most, if not all known forms of life, require other forms of life in order to survive. Many use other life forms in their reproductive process—many species of plants require that animals carry their seed to new places in order to best spread out. Flowers often use insects to pollinate—without the insects, pollination and therefore reproduction would be essentially impossible for them. Autonomous self-reproduction is a tricky term, seeing as reproduction is an enormously complicated process for so many forms of life, and using it as a characteristic of life is problematic in that it is so ambiguous.

Viruses are simple in construction—however, their interaction with more structurally complex organisms is anything but. While their process of reproduction is simple, viruses cause vastly different reactions in all the different forms of life they infect. The common cold, herpes, and HIV all are viruses that effect humans, but each works on different cells in different parts in the body to create vastly different symptoms in the host. Many viruses do not kill their host. Some, like herpes, can live in a host for an entire lifetime, feeding off of the cells but not killing the system. Some, like the common cold, are easily overtaken by a healthy immune system's antibodies. Others, like HIV, inevitably destroy their hosts, self-destructing along with them. These examples show the complicated cycles of viruses. It would be unconventional to say that a kind of rhythm is a characteristic of life, but surely many would agree that life does move in a rhythmic way.

Surely rocks do not behave similarly. Viruses have a relationship with life, for sure, in both their similarities in genetic/protein structures and in the fact that viruses require life. Giving up the requirement that things must autonomously self-reproduce in order to be alive eliminates most of the debate about calling viruses alive, and, so, for the purposes of this paper, we will do just that. So, now that we assume something like a virus is alive, we have a problem in front of us. What else, then can be considered alive in this framework? Surely a self-replicating nanotechnology is possible. Scientists already use viruses as tools in genetic study, carrying specific genes to cells. (2) Should we then consider these tools alive? The difference between them and the naturally occurring virus is insignificant.

Why is it that we feel uncomfortable calling our own creations "living"? That the virus arose from the natural world creates in us a sense that it should at least be considered half-living. However, very small self-replicating machines do not seem to fit comfortably in any of the standard definitions of life. Viruses are made up of organic material similar to what exists in our cells—if we build machines out of this material, could we then call it "alive"? We must, if we consider viruses to be alive. Still—as of now, all life has arisen out of the natural world, not out of human construction.

The debate concerning the status of viruses continues—and we have not answered any questions, only explored reasons why there is this problem of defining "life." This discussion does hint at an interesting trend—life seems to be composed of complicated interactions based in some kind of self-reproduction. The more we allow for simpler things to be alive and the less terms we ask of things in order to consider them alive, the more we have to consider wilder conceptions of what it means to be alive. Weather systems, planetary systems, even molecules all might some day fall under such a definition. Surely our own creations will someday be causing fierce debates. Already people fight over the imagined nature of A.I.—which, if "alive," will not necessarily reproduce nor will have an earthly body of the sort every other kind of life does.

Life must not be containable in any kind of principle or rule. Instead, it seems to be only containable in an idea of a community; in an idea of a specific kind of system and the parts of that system. With that kind of definition, we may be able to approach the future with a new and open mind for what we might find, alive, half-alive, machine, or otherwise.

(1) CellsAlive Homepage (2) Wikipedia's Virus Page (3) Wikipedia's Life Page (4) Virology.net


Full Name:  Nick Krefting
Username:  nkreftin@haverford.edu
Title:  Assessing the Threat: The Potential Avian Influenza Pandemic
Date:  2005-11-13 11:57:31
Message Id:  16946
Paper Text:

<mytitle>

Biology 103

2005 First Paper

On Serendip

Recently, there has been a lot of media coverage on a relatively new strain of avian flu in Asia. This strain has infected a small number of humans in a few Asian countries, but the implications of these few infections are potentially disastrous. Government officials, and obviously health organizations, are concerned about the risk of a mutation in this strain that could lead to a pandemic. (1) An epidemic is an illness that affects a relatively large proportion of a given geographical population; a pandemic is an epidemic that affects a much larger geographical area. This paper aims to assess the potential risk of the current situation, but first it is necessary to examine some background information on influenza viruses in general.

There exist three general types of influenza – A, B, and C. Types B and C generally affect only human, and neither cause pandemics. Type C usually only leads to a mild illness, and though B is typically more dangerous, its spread has remained limited to epidemic status in the past. The current avian flu is type A influenza. Type A is a broad category that affects a number of species, and is divided into various subtypes, which are then further divided into strains. The term "subtype" refers to the "type" of two proteins on the surface of the virus: hemagglutinin (H) and neuraminidase (N). There are various subtypes of these two proteins, leading to a wide variety of subtypes for the influenza A virus. These subtypes are named according to the type of both proteins present – for example, the first of each type is designated H1N1. (2)



The subtype that is currently threatening pandemic status is the H5N1 influenza A, which is primarily carried by and transmitted between birds. (3) In 2003 and early 2004, there was an outbreak of H5N1 in eight Asian countries that caused the deaths of over 100 million birds. The subtype reemerged months later, and the current outbreak has not yet subsided. (4) As of October, infected birds have been found as far west as Turkey, Croatia and Romania. (5)



This spread of the virus is not immediately harmful to humans; it is the potential of the virus to mutate that creates a problem. The current strain of the H5N1 virus has an extremely low rate of transmission from birds to humans; just over 100 people have been infected since the first appearance of the virus in 1997, a negligible number compared to the multitudes of infected birds. (6) The virus in its present form is also not transmissible between humans. Thus, in its current incarnation, the virus is not terribly dangerous, though, if certain conditions were met, the virus could become extremely dangerous.



The first alarming fact about H5N1 in humans is that, of the few humans who have been infected, over half have died from the illness. (6) Even this fact fails to be that significant if humans catch the virus only rarely. The known nature of viruses, however, dictates that there is a lurking threat in the form of a mutation. Though not currently transmissible between humans, every infection of a human by a bird increases the likelihood that H5N1 will mutate to form a strain that can be transmitted from human to human.



All this raises some extremely frightening questions, many of which simply cannot be answered. The virus needs only one mutation in order put the human population in very direct danger of a pandemic. Vaccinations are not yet developed, of course, because the human-to-human strain, from which we could derive the vaccine, has not yet evolved. What, then, can be done to prepare for a pandemic? How widespread would it be? How worried should a citizen of the world be about contracting a fatal strain of H5N1?



Various sources treat the possibility of the pandemic with slightly different levels of seriousness. The most sensible information is put out by the WHO, which is concerned about health risks for the entire human population. Their avian flu fact sheet (6) emphasizes that the threat of the necessary mutation is ever-present and becomes increasingly potent as the geographical area of infected birds grows. They urge countries take all possible action before the pandemic to prepare, and warn countries to follow plans (developed by the WHO) for isolating the virus and minimizing its spread during a pandemic situation. (7) This is extremely practical and reasonable information, urging decreased interaction between humans and birds who could be carriers to try and stem the tide. This focus on prevention, if listened to, could be extremely useful; just in case, though, the WHO still provides instructions in the event of an outbreak. Overall, their advice is useful, and could easily prevent a worst-case scenario.



The CDC of the United States treats the avian flu seriously, but they have a different angle from the WHO. The CDC downplays the immediacy of a pandemic event, and their fact sheet (4) suggests that the best strategy is very close surveillance rather than immediate preventative action. This probably stems from the CDC's status as a US organization, concerned primarily with health risks to US citizens – Americans can not take as much preventative action as can citizens of Asian countries. Similarly, the CDC prioritizes the eventual importance of vaccines over preventive measures. This strategy is echoed by a recent $7.1 billion bill proposed by President Bush, of which all of the money will be spent on researching or buying vaccines and buying antiviral medication. (8) In America, the pandemic is not seen as an immediately preventable threat, but rather as a distantly inevitable threat.



That being said, both agencies agree that the risk of a pandemic is very serious and that precautions should be taken. Most of the difference between the two approaches lies in their assessment of the probability of a H5N1 pandemic affecting the population with which they are concerned. The WHO's overall plan, while it does include plans for vaccination and antiviral medication, spends much more time on practical methods for reducing the threat of the pandemic. This, to me, seems a far saner method. Prevention shouldn't be left out of the picture just because it doesn't affect one portion of the population as strongly.



1) "Administration's Flu Plan Gets Mixed Reception in Congress", New York Times 11/3/05.



2) The CDC's Influenza Virus Fact Sheet.



3) National Biological Information Infrastructure's Overview of Avian Influenza.



4) The CDC's Avian Flu Fact Sheet.



5) The WHO's Avian Flu Timeline.



6) The WHO's Avian Flu FAQs.



7) WHO's Recommended Strategic Actions in the event of an Avian Flu Pandemic.



8) "Bush Announces Plan to Prepare for Flu Epidemic", New York Times 11/2/05.