Monday, July 11, 2011

xenotransplantation

If you order your research paper from our custom writing service you will receive a perfectly written assignment on xenotransplantation. What we need from you is to provide us with your detailed paper instructions for our experienced writers to follow all of your specific writing requirements. Specify your order details, state the exact number of pages required and our custom writing professionals will deliver the best quality xenotransplantation paper right on time.

Out staff of freelance writers includes over 120 experts proficient in xenotransplantation, therefore you can rest assured that your assignment will be handled by only top rated specialists. Order your xenotransplantation paper at affordable prices with livepaperhelp.com!



Over three thousand patients die each year while awaiting organ transplants. They die from heart, kidney, lung and liver failure. End-stage organ failure is one of the most important public health problems facing Americans today. Although this is a serious problem, scientists may have found a solution. That solution is known as xenotransplantation.


Good afternoon. My name is Sarah Cougill and I am proudly representing the Fairfield FFA. I am here today to talk to you about a new biotechnological subject known as xenotransplantation.


Xenotransplantation refers to procedures that use living, non-human animal cells, tissues, or organs for human therapeutic purposes. (HHS Fact Sheet, n.p.) Interest in xenotransplantion has reappeared recently. One reason for this sudden reappearance is that human-to-human transplants or allotransplantation have become extremely successful. This success has caused a demand for human cells, tissues and organs. However, the supply of these human cells, tissues and organs has not met the demand and xenotransplantation has been looked to for a possible solution. Scientific advances, such as potent new immunosuppressive drugs and the development of genetically engineered animals, also are increasing the chances of successful xenotransplantation outcomes. (HHS Fact Sheet, n.p.)


Since the 170s, the number of organ transplants performed each year in the U.S. has rose from 1,618 in 188 to about ,000 in 18. The number of patients on waiting lists for organs has rose from about 14,000 in 188 to 68,500 today. Some of these patients are in extremely urgent need of an organ. The amount of organ donation does not have a healthy growth rate. In 188, the number of donors amounted to 5,06 to ,1 in 18. Almost 5,000 people die each year, approximately 1 each day, while waiting for a transplant.


Custom writing service can write essays on xenotransplantation


Some of the animals that scientists have discussed using for xenotransplantation include pigs and baboons. The use of primates, especially chimpanzees, has been ruled out because of their close relatedness to humans and for fear of making them extinct. Pigs, on the other hand, are intelligent, used as a source of food, are distant from humans phylogenetically, and fall much lower on the personhood scale. (Agnew, n.p.)


One of the benefits of xenotransplantation is that patients will not have to wait for long periods of time for donors. Also, the transplantation of Pancreatic Islet cells can cure diabetes, the implants could treat Parkinson’s and Huntingdon’s disease, multiple sclerosis and the effects of strokes. (What is Xenotransplantation, n.p.) With the use of xenotransplantation, there will be an unlimited supply of organs; fresh harvesting of organs that helps avoid the effects of death on organs, infection free donors, and modification to donors. Pigs are good candidates for being used as donors. Pigs are already present in large numbers and millions are slaughtered for food. Pig organs have a relative size that makes them a good size-match for humans. The cost of pigs is also much lower than any other alternative. Pigs can also be bred to make them more compatible with humans.


A disadvantage of this idea is that the cost of xenotransplantation will be very expensive. In 16, The Institute of Medicine estimated costs to be about $0 billion a year. Alan Berger, a member of the Secretary’s Advisory Committee on Xenotransplantation, estimates surgery itself will be anywhere from $15,000 to as high as $40,000 or $450,000 dollars. Another concern of the public is the chance of infecting patients and others with recognized or novel infectious agents transmitted from xenotransplants. Many fear that xenotransplantation will increase the risk of transmitting infectious agents. Also, pigs contain a galactose sugar as part of their genetic information that is known to the human immune system as a virus or bacteria. The human immune system attacks these sugars, destroying the organ and causing organ rejection and failure. Organ aging seems to be another problem. One human year is equal to years of a pig. It is not known if this rate of aging would occur in a human. Another concern is the risk of spreading porcine endogenous retrovirus (PERV) to humans. Although this causes no harm to pigs, it may play a part in resistance to infection. Some ethical issues regarding xenotransplantation are animal rights, allocation of resources, and distributive justice.


To overcome the possibility of spreading infectious agents, a new line of pigs free of viruses has been bred. Also, using the cloning technique, scientists have produced four piglets without one of the two genes that lead to rejection. Human antibodies could also be bound to pig sugars to lessen the effect, but not the outcome. With antibody synthesis, the human body would cause rejection in less than five minutes. Some scientists also believe that it is possible to remove the pig sugar from the pig’s genetic makeup through gene therapy.


In 14, 4 year old Maribeth Cook had a stroke that left one side of her body paralyzed. In 1, she volunteered to become one of five stroke victims to participate in an experimental treatment using pig neural cells transplant. Maribeth had 0 million fetal pig cells implanted into the part of her brain that received damage from the stroke. Since the operation, she has completed a half-marathon, although she needs a leg brace to walk. Maribeth’s thought processes are much clearer and her speech has improved since the operation. Maribeth was part of the early, Phase 1 clinical trial by the biotech company Diacrin to see if xenotransplants helped victims of strokes.


In 1, 1 year old Amanda Davis suffered a massive stroke that paralyzed her left side. She decided to have a pig neural cells transplant, but risked herself. She could become infected with a pig virus that could become a major health risk. Doctors suggested that Amanda should not have children because the long-term effects are unknown. Amanda signed a medical research consent form that will govern the rest of her life. This means no blood donations, safe sex, and recording of her partners. Amanda also has to agree to follow up for life and access to her tissues after her death for research studies. A week after her transplant, Amanda has a seizure and further trials were halted while doctors tried to figure out why. In the ten months that have passed since the treatment, Amanda has had no more seizures and can walk easily without her brace.


Jim Finn spent 0 years of his life with Parkinson’s disease. He was at end-stage Parkinson’s. Jim couldn’t walk, talk, or use his hands. In 17, he became part of the experimental clinical trial. Jim had millions of fetal pig neural cells injected into part of his brain. Six months afterwards, he could walk by himself and get up and sit down from a chair. His neurologist said his improvements were remarkable.


In 17, Robert Pennington was facing acute liver failure and there was currently no human liver available. His surgeons suggested hooking him up to several pig livers outside of his body, which would filter his blood and keep him alive until a human donor was found. For seven hours over three days, Robert was attached to a pig liver from a transgenic pig. Then, a human liver was found. Pennington was one of a half dozen patients whose lives were saved using pig livers.


Some examples of cross-species virus transmission include bovine spongiform encephalopathy, filoviruses, hantavirus, human immunodeficiency virus, influenza, and nipah virus. Bovine spongiform encephalopathy or mad cow disease, is carried by cattle and causes Creutzfeldt-Jakob disease in humans. Filoviruses include Ebola and the Marburg virus, which cause severe hemorrhagic fever in humans. The hantavirus is transmitted by rodents and causes hemorrhagic fever and pneumonia. Human immunodeficiency virus comes from chimpanzees. Influenza goes from birds to pigs to humans. It has been known to kill 0 to 40 million people in 118, being labeled as the Spanish flu. The nipah virus occurred among pig farmers. This virus causes a form of viral encephalitis, an inflammation of the brain.


As of today, it is very unlikely that xenotransplants will be risk-free. The only way to avoid or help prevent diseases is monitoring of patients, recording of sex partners, and limited human trials. In time, many issues revolving around xenotransplantation will be resolved and xenotransplantation will move closer to becoming reality.











Please note that this sample paper on xenotransplantation is for your review only. In order to eliminate any of the plagiarism issues, it is highly recommended that you do not use it for you own writing purposes. In case you experience difficulties with writing a well structured and accurately composed paper on xenotransplantation, we are here to assist you. Your persuasive essay on xenotransplantation will be written from scratch, so you do not have to worry about its originality.

Order your authentic assignment from livepaperhelp.com and you will be amazed at how easy it is to complete a quality custom paper within the shortest time possible!



No comments:

Post a Comment

Note: Only a member of this blog may post a comment.