Xenotransplantation

1. Xenotransplantation 第二組 賴昱辰 陳宛均 歐子嘉 陳品汝 莊婉庭 鄭皓中

2. Main ideas of the first paragraph • 1. Organ transplants have great advantage to people but have its problem. • 2.Some people can be on waiting lists for long time before receiving organ, then die.

3. First Paragraph--words and phrases • Organ器官 (n):a part of the body with a specific function necessary for survival • Transplants移植(n): the moving of an organ or tissue from one body to another • Sophisticated廣泛的,高度發展的(a):having refined or cultured tastes and habits • Waiting list候補名單,等候批准的申請名單(phr):a list of people waiting to obtain some object, treatment, status, etc • Much-needed非常需要(n): need it very much

4. Organ transplantshave saved millions of lives around the world. Over the years, transplants have become much more sophisticatedand now have a very high success rate. The problem is that it is difficult to find organs. People can be on waiting lists for years before receiving their much-neededorgans, and many die while waiting.

5. Main ideas of the Second paragraph • 1. The demand for donated organ is increasing while the supply is decreasing. • 2. The medical community is looking for organs that can be used in humans from animal kingdom.

6. Second Paragraph--words and phrases • trend趨勢(n):general tendency or direction • accidental偶然的(a):nonessential; incidental • donor捐贈者(n):a person who makes a donation • Law enforcement法律的執行(phr) • effectively有效地(adv):smartly • deter防止(v): to discourage (from acting) or prevent (from occurring), usually by instilling fear, doubt, or anxiety • driving傳動(v): having or moving with force and violence • community團體(n): the people living in one locality • Kingdom(生態)界(n): any of the three groups into which natural objects may be divided: the animal, plant, and mineral kingdoms

7. The problem is getting worse, as the demand is increasing while supply is decreasing. The reason for this trend is that the population is getting bigger while accidental deaths are decreasing. Most organ donorsare victims of car crashes; they were healthy people with healthy organs who were unfortunately killed.

8. As safety standards improve and as law enforcement more effectively deters dangerous driving, fewer people are dying in car crash.This is, of course, a positive development, except that it decreases the number of healthy organs available to those who need them. So the medical community is now looking to the animal kingdom for organs that can be used in humans.

9. Main ideas of the third paragraph • The problems and solutions of the rejection of transplanted organs.

10. Third Paragraph--words and phrases • Xenotransplantation— a transplant utilizing an organ from a different species than the recipient. • Immune system— the system in the body that protects it from disease. • Genetic modification—the altering of genes for a specific purpose • Clone—to create an exact genetic copy. • Breed—to mate in order to produce offspring.

11. No doctor to date has successfully performed an animal-to-human organ transplant, known as xenotransplantation. The first major concern is the possibility that human’s immune system will reject the organ. The human immune system is programmed to reject and attack foreign bodies in order to keep the body health.

12. Rejection was a problem in the early days of human-to-human organ transplants as well. But over the years anti-rejection medicines have been developed with tremendous success. These drugs probably will not work by themselves when the organ of a different species is introduced, so further measures need to be taken. Rejection(n)排斥、拒絕、抵制 Tremendous(adj.)巨大的、廣大的、龐大的 Anti-rejection(n)抗排斥反應

13. Genetic modification of the organ seems to be one way to reduce the risk of organ rejection. For example, pigs which are the ideal candidate for xenotransplantation, have a gene called alpha-gal, which can be modified to trick the human immune system into recognizing it as human. Candidate(n)人選、候選人 alpha-gal (n) α-半乳糖苷酶 Modified(adj)修改、修飾、修訂

14. The procedure has shown success in pig-to-monkey transplants, which makes it promising for humans. After having altered the gene, scientists could then clone the pigs with the altered gene and eventually breed them conventionally. Pigs breed quickly and have large litters, so large supply of organs ready for transplants could be produced this way.

15. Main ideas of the forth paragraph • Transplanting organs will cause virus infection which brings harm to human, but there are methods found to prevent virus from entering cells.

16. A second concern is the possibility that the donor organ could contain viruses that would infect the human body. Anti-rejection drugs, which would have to be used post-operation to ensure that the body continues to accept the new organ, suppress the immune system.

17. Main ideas of the fifth paragraph • Another animal that seems likely to be a candidate for xenotransplantation is the baboon because it is genetically very similar to humans. • The main problem with baboon organs is that they carry many viruses.

18. This makes the person more susceptible to infection, Pigs’ DNA contains a virus that is harmless to pigs but could prove fatal to humans. Fortunately, scientists have identified a type of pig that does not carry this virus as part of its DNA. Scientists are also working on ways to prevent the virus from replicating by identifying the receptors that allow the virus to enter a cell. Susceptible- {adj}易受影響的- is a member of a population who is at risk of becoming infected by a disease, or can not take a certain medicine, antibiotic. Receptors-{n}感覺器官-part of the surface of a cell which allows molecules. Infection- {n}傳染-is the invasion of a host organism's bodilytissues by disease-causing organisms, their multiplication, and the reaction of host tissues to these organisms and the toxins they produce

19. Another animal that seems likely to be a candidate for xenotransplantation is the baboon because it is genetically very similar to humans. This decreases the likelihood of rejection. In fact, baboon-to-human transplants have been attempted, without success. Candidate-{n}候選人- is the prospective recipient of an award or honor, or a person seeking or being considered for some kind of Likelihood-{n}可能性-captures the idea that something is likely to happen or to have happened. Attempted-{adj}企圖的-To try to move , by entreaty , by afflictions , or by temptations ; to tempt .

20. The patients died of virus infections, however, and not because the body rejected the foreign tissue. the main problem with baboons organs is that they carry many viruses. furthermore, and like pigs, baboons reproduce slowly, like humans, they do not have large litters, so it would be difficult to breed the numbers of baboons that would be necessary to meet the demand for organ transplants. *Tissue組織-any part of a living or dead body

21. Another advantage of using pigs is that they do not pose the moral dilemma that baboons do. Of course, some animal activist will argue that it is always wrong to kill an animal for the benefit of humans. but given that pigs are already raised for slaughter, the idea of using them to save human lives will not present a new ethical issue. Dilemma(n)困境 Baboons(n)狒狒 Ethical(adj)合乎道德的 Benefit(n)好處、利益