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Research News Australia Korea Australia Finds New Chinese Man with Hope in Treating Cystic Transplanted Hands Cuts Fibrosis His Birthday Cake Australian researchers have found a way of A young man, who has fully recovered after receiving preventing the stubborn bacterial that clog an allogeneic transplant of two hands, has recently marked the lungs of people with and eventually his 20th birthday in a hospital in Harbin, the capital city cause their deaths. They hope their research will of northeast China’s Heilongjiang province. improve the survival rates of people with this Mr. Gao Liang, the patient, cut the cake with his new common genetic disease and also improve hands and handed out pieces to doctors and nurses in the control in hospitals. Faculty of Clinical Medicine of Harbin Medical University, About 2500 Australians have cystic fibrosis, a where he received the transplant in January last year. disease characterized by a build up of thick mucus in the lungs and pancreas leading to breathing Dr. Zhang Xinying said that it is no mean feat for Mr. difficulties and nutritional problems. Gao to cut the cake with his hands, adding that it proves that the functions of his hands have virtually recovered. The lungs of most victims also become infected with the , a Mr. Gao said that he can now brush his teeth, wash persistent and chronic infection causing his face, comb his hair and put on his clothes with his inflammation and damage to lung tissue. But new hands. He said that he is happy and even won in an researchers from Brisbane’s Institute of Molecular arm wrestling bout at his party. Bioscience have found that the severity of these Severe frostbite caused him to lose his hands and legs. bacterial can be reduced or even prevented He had artificial legs fitted in another hospital. According by using an enzyme that breaks down DNA. to medical records, Mr. Gao’s case is the fourth successful Dr. John Mattick, co-director of the institute, one in the world and the second in Asia. said, “During lung infection pseudomonas aeruginosa creates a , a soup rich in proteins, Compared with heart transplants and other single complex sugars and DNA. This biofilm plays a vital organ transplants, hand transplants are much more role in establishing bacterial colonies that are also complicated, involving even more systems and tissues such resistant to and the host’s immune as skin, tendons, blood vessels, nerves and bone marrow. response.” He said, “Scientists have known for a These lead to very low success rate of such trasplantation. while that the biofilm of this pathogen has a high The development of advanced medical technology DNA content. Our research showed that treating the biofilm with an enzyme called dnaseI, which breaks to reforge human limbs and reduce immunological down DNA into its component molecules, destroys rejection has made hand transplants a reality. the biofilm and restricts the establishment of One year of close observation showed that Mr. Gao infectious colonies.” suffers no side effects from the medicines he took to prevent Dr. Cynthia Whitchurch, a molecular biologist immunological rejection, and the nerves of his hand grow at the institute, said that pseudomonas infections by 3 mm daily. Mr. Gao now takes a much smaller dose caused the death of about 95 percent of people with of medicine compared with other people who have cystic fibrosis. Ideally, the DNA-destroying enzyme transplanted hands. would be used to prevent pseudomonas infections occurring. To date, ten similar operations have been completed But, so far, research has been done only in test in the world, seven of which are performed by Chinese tubes and clinical trials are still some way off. Dr. doctors. Among the total population of 1.3 billion, China Whitchurch said that the DNA-destroying enzyme currently has more than 8.5 million people with deformed could also have other applications. limbs.

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publication in the journal Science. Dr. Rod Wing, China Reveals Rice director of the Clemson University Genomics Institute Genome Sequence and the former US representative to the IRGSP, said, “Rice is the rosetta stone for cereals. The world Marking a milestone in plant-genomics research, population will double in 50 years. We have to know scientists in China have made public a sequence of a everything we can about the most important food crop widely grown rice strain that has never before been in the world. Knowing this sequence now will accelerate sequenced. The results of the indica strain sequence everything. Understanding indica together with the was presented to the 10th Annual Plant, Animal & anticipated public release of japonica will also allow Microbe Genomes Conference held in Beijing by the research not possible with only one genome alone.” Beijing Genomic Institute (BGI). Dr. Ed Kaleikau, director of the plants division at the US Department of Agriculture, said, “Rice is a model The sequencing effort of the indica strain for all cereal plants. Its sequencing will lead to the yielded 386 million base pairs in a six-fold identification of genes not only important in rice but in coverage, and an initial analysis showed that other cereals. Eventually it will lead to a better the genome contains approximately 60 000 understanding of rice and all cereal crops including to 65 000 genes. wheat, barely and corn. For important plants, this could be compared to the sequencing of the human genome. The Oryza sativa indica strain, which accounts for A better understanding of plant biology is now available the majority of rice grown in China, has never before for the second largest plant kingdom.” been sequenced. Preliminary results of the BGI project, begun in May 2000 and completed in October 2001, was published in the Chinese Science Bulletin when its draft was complete. However, the extent of the work remained virtually unknown outside a cadre of Chinese genomics researchers until the team presented their Shanghai Cancer Survey findings during the conference. Seeks Effective Treatments According to Dr. Jun Yu, a member of the team, BGI researchers sequenced the indica strain using a A large-scale survey among cancer sufferers is to whole genome shotgun approach. The effort yielded be carried out in Shanghai as medical chiefs seek more 386 million base pairs in a six-fold coverage, and an effective treatments for the debilitating disease. Starting initial analysis by BGI researchers showed that the in March, the survey will be conducted among 10 000 genome contains approximately 60 000 to 65 000 cancer patients in Shanghai and its neighboring cities. genes. Currently, the organizers, Shanghai Cancer The effort, which independent researchers are only Recovery Club, Shanghai University of Traditional now beginning to analyze, is the first rice genome to be Chinese Medicine and Shanghai Green Valley released to the public. Last January, Syngenta and Corporation, are enrolling volunteers and patients Myriad Genetics announced the draft sequencing of the willing to participate in the survey. japonica strain, but the companies have yet to release Dr. Yuan Zhengping, director of the club, said, “The those data. survey will follow each participating patient for a year. An international public consortium, the Such a large-scale survey is unprecedented in China.” International Rice Genome Sequencing Project (IRGSP), The survey will be composed of questions on non- is set to finish its own sequence of the japonica genome medical methods (such as physical training and by the end of 2002. The IRGSP, which includes the US, attitudes) in determining their contribution to the Japan, and China, is performing the sequence using the recovery of cancer patients. Other questions will center BAC by BAC approach which when compared with around the importance of social support and family whole-genome shotgun sequencing is more time- care, and the relationship between C-type character intensive. (reserved, unwilling to vent their unhappiness) and The Chinese sequencing data are under review for cancer cells.

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Statistics show that the incidence of cancer in was reduced, the authors suggest that the immune Shanghai is among the highest in China. systems of the mice may not be able to fight off infection. Every year, 43 000 local residents fall victim to the The authors caution that the factors affecting clone disease, of whom 34 000 resulted in death. And this longevity are many and subtle, including genetic figure is continuing to rise. Research has found that the background and the type of cell from which the nucleus majority of Chinese cancer patients survive during is taken — the so-called donor cell. operations, radiotherapy or chemotherapy. Instead, they Dr. Ogura said, “There may be reprogramming error succumb while recuperating after routine hospital which may have unpredictable effects in the long run.” treatment. Dr. Yuan said, ‘’How to help them better Reprogramming error is thought to occur when a cell recover after receiving routine treatment in hospital is already assigned to a bodily task — in this case in the of vital importance to cancer patients.” testis — is “reset” in preparation for cloning and development into an embryo.

Japan “This study reinforces the opinion expressed by many that clones are not entirely normal and that we should be careful about how we use this technology,” said Dr. David Solter, a biologist at the Max Planck Tokyo Scientists Find Institute of Immunobiology in Freiburg, Germany, who Cloned Mice Have Shorter is not involved in the Japanese study. Dr. Ogura said, “We are continuing tests on the Lives immune system of cloned mice using other genotypes Scientists at the National Institute of Infectious (mouse strains).” He stressed that public concern about Diseases in Tokyo, Japan have recently found that cloning should be guided by science. He said, “In this cloned mice have shorter life spans than mice conceived context, we think that our study provides a scientific naturally. basis for public concern about human reproductive cloning.” With Dolly the sheep, the first cloned mammal, suffering from premature arthritis, and previous studies showing that cloned animals tend to be obese and may have higher rates of immune dysfunction, the Japanese study will add to worries about the long-term effects of Gene Study Sheds Light cloning. on Alzheimer’s Disease

With Dolly the sheep suffering from premature Researchers at Osaka University have recently achieved a breakthrough in determining the cause of arthritis, and studies showing that cloned Alzheimer’s disease, raising hopes for improvements animals tend to be obese and may have higher in the treatment of the currently incurable ailment that rates of immune dysfunction, this study will add reportedly affects 1 million Japanese aged over 65. to worries about the long-term effects of cloning. Using sophisticated scanners, seven medical researchers headed by Dr. Masaya Tohyama studied This work is the first to link cloning with premature mutations in three genes known to be related to the death. Dr. Atsuo Ogura and his colleagues examined cause of Alzheimer’s. Under hypoxic conditions — a 12 mice cloned from immature cells in the testis. The lack of oxygen due to an accumulation of hyper-free cloned mice started to die after 311 days, with ten of radicals, a mutation in a gene called PS2 is caused when the 12 dying before 800 days. Only one of seven the protein HMG-I binds itself to the end of an exon, a naturally conceived mice died before 800 days. gene fragment that allows DNA to be read, within the PS2 gene, resulting in an aberrant splice between exons An examination of six of the clones revealed severe 4 and 6. pneumonia and liver failure, which was not observed in the normal mice raised under controlled experimental The shortening of the exon sequence generates a conditions. As antibody production in the cloned mice PS2-variant gene. This mutation then affects other agents

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resulting in a buildup of abnormal or unfolded proteins. Prefectural Medical University’s Department of The cell, or cells, eventually die and lead to a loss of Neurology and Gerontology. memory and greatly impaired motor skills, known “Results from this research will not be seen in the clinically as dementia. near future, but perhaps in 10 years,” Prof. Mizuno said. “Although several genetic diseases are known to “It will be a large, ongoing project to make an effective be caused by mutations, the study of the factors that drug and even then there are other causes that will have modulate the splicing of normal genes has not been to be addressed. But in Japan, dementia is the most well documented,” said Dr. Taiichi Katayama, a research serious social and medical problem, and this research associate at Osaka University and spokesman for the is absolutely necessary.” project. Based on the discovery of aberrant splicing in The drugs, when and if they arrive, will also be the PS2 gene, the group was then able to experiment expensive, according to Dr. Katayama. The time and with various countermeasures. cost to universities and pharmaceutical companies will mean high prices for medicines, and large profits for The discovery is related to patients affected with the organizations involved. the “sporadic” form of the illness, a slow buildup Firms that include Eisai Co. Ltd. and Yamanouchi of beta-amyloid in the brain, as opposed to the Pharmaceutical Co. Ltd., both based in Tokyo, in “familial” strain, which is the result of a certain conjunction with European and US companies, have inheritance pattern and affects less than ten already begun marketing drugs to slow the progress of percent of sufferers. Alzheimer’s in its early stages. In the case of Eisai, sales of these and other “We designed a decoy RNA sequence that affected neurological drugs will account for nearly a third of the the relevant cells and stimulated these cells under company’s profits this fiscal year, according to officials hypoxic conditions,” Dr. Katayama said. “We found that of the firm. Further spurring the race to find treatments the number of PS2-variant genes was decreased and and cures is the high cost borne by families and that the buildup of unfolded proteins was thus governments for treating Alzheimer’s patients. inhibited.” Though statistics are hard to come by in Japan, the The group’s findings will be published later this Alzheimer’s Association in the US estimates that the year and plans are going ahead for clinical experiments lifetime cost per patient for treatment is around US$174 to be conducted in the laboratories of Tokyo-based 000, while businesses incur just over US$3 billion Taisho Pharmaceuticals Co. Ltd. to try to come up with annually in related costs. an effective medicine.

The importance of such discoveries is significant Korea in a country like Japan, where government statistics show that by 2050, over a third of the population will be 65 or over. This, coupled with an estimated drop in the population of some 27 million between 2006 and Korean Researchers to Use 2050, means the scramble is on to find a cure for Alzheimer’s. DNA Chips for Cancer However, there are several causes of the disease, Study ranging from genetic mutations to vascular constriction. The Korean Ministry of Science and Technology Dr. Katayama explained that the group’s discovery (MOST) has recently announced that it will provide DNA is related to patients affected with the “sporadic” form chips containing genetic information on stomach cancer of the illness, a slow buildup of beta-amyloid in the to local researchers. brain, as opposed to the “familial” strain, which, although pathologically the same, is the result of a The DNA chips are made by the Center for certain inheritance pattern and affects less than ten Functional Analysis of the Human Genome, affiliated percent of sufferers. Cures are still a long way off, to MOST. Called “14k DNA chip”, they contain according to Prof. Toshiki Mizuno, a professor at Kyoto information on 14 000 types of functional genes derived

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from stomach cancer cells and the normal stomach tissue believe it. I think it is very interesting. But work needs of Koreans. to be done.” The center has thus far secured 670 types of genes The most unusual aspect of the Mexican trial is that are thought to cause stomach and liver cancers. Yet that the 12 teenagers are not given any drugs to the center has so far relied on DNA chips that were based suppress their immune systems, which would on genetic information from abroad. normally destroy any cells from other animals. Instead, the insulin-producing islet cells from MOST said that this is the first time in the world that newborn pigs are inserted in cigarette-sized capsules DNA chips incorporating genetic information unique to just under the skin, using sertoli cells from the testicles an ethnic group have been produced. “The new DNA chip to protect the foreign cells from attack by the immune contains genetic information unique to Koreans so it is system. expected to facilitate research on the cause of the cancer and advance the development of a treatment,” a ministry Sir Roy also said that it is unusual to insert the official said. pig cells just under the skin, instead of next to the liver. The center plans to offer another DNA chip based on 10 000 human genes brought from the US, the “10k human He is negotiating a collaborative research project DNA chip” and a “9.5k mouse chip” to researchers in the with Diatranz medical director Dr. Bob Elliott to test ministry and relevant companies. variations on the procedure in animals — initially pigs and rats. “We are hoping to study what happens, According to an official of the center, the team will to see what the optimum numbers of sertoli cells are make 1000 DNA chips for stomach cancer research this vis-a-vis the islets to get the best results. I would also year and plans to produce DNA chips for liver cancer use like to study putting the same islet/testicle cell mix in 2003. The research team will offer the chips to cancer into the abdomen where they would go first to the researchers at a low cost and store the results in its liver.” database. He expects to do the research — which will take about two years — at the National University of Singapore, where he is a visiting professor. New Zealand In the long term, Diatranz believes the procedure may provide a cure for the world’s 15 million Type 1 diabetics, who have to inject insulin several times a Pig Cell Procedure day. Pioneered by NZ Firm Spurs Diabetes Study Singapore British transplant surgeon Sir Roy Calne plans to investigate the apparent breakthrough in diabetes treatment by Auckland research company Diatranz and Mexican surgeon Dr. Rafael Valdes. Singapore World First to Sir Roy examined Dr. Valdes’ 12 Mexican patients Use Cord Blood for who were given transplants of Diatranz’ insulin-producing pig cells last December, and confirmed that one girl has Cancer Treatment been able to stop taking insulin injections completely for Singaporean doctors have cured two cancer the past five months. patients by using blood from umbilical cords, without But Sir Roy has recently acknowledged that the long- first destroying their bone marrow with term effect of the transplants is still unknown, and he wants chemotherapy. Their success is a world first. to test the procedure in animals. “I thought this is some One of the patients had leukemia, or cancer of extraordinary biological phenomenon and do not fit in the blood; the other had myeloma, or cancer of the with standard technology, therefore most people do not bone marrow. Both had undergone conventional

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v6n5-pt2 158 3/7/02, 11:11 AM Research News treatments, but suffered relapses. However, Associate Prof. Patrick Tan, head of Singapore General Hospital’s Thai and US Medical (SGH) Department of Hematology, said that it will be another three years before they can be sure they are Researchers Join Hands fully cured. on Drug Project Their success has made doctors at SGH hopeful it An American-Thai joint research project on could become the main way of treating fatal blood methamphetamine addiction will be led by world- disorders. Prof Tan said, “If we can show in three years’ renowned American medical researcher Dr. Walter Ling. time that a cure is achieved in a high percentage of The research project is believed to be the first of its patients, this could become the treatment of choice.” kind and the most intensive ever. Currently, leukemia patients have only a 20 to 30 The group’s research will include the evaluation percent chance of survival. The patient with leukemia, of medications and the development of psycho-social a 43-year-old businessman who wanted to be known strategies for the treatment of opiate, cocaine, only as Mr. Huang, underwent chemotherapy before methamphetamine, alcohol and nicotine abuse and having some of his bone marrow removed when he dependence. was diagnosed in September 1999. The project is expected to take up to five years, Before the bone marrow was replaced, he was involving research on symptoms of addiction, given more chemotherapy this time in high doses, in withdrawal symptoms and the responses to behavioral the hope it would overcome the cancerous cells. But therapy. The research will be divided between the US this did not happen. At that point, he was expected to and Thailand, to find ways of treating, rehabilitating live for about six to 12 months more. and preventing addiction using medical and behavioral Doctors then gave him umbilical-cord blood from therapies. two babies, one in Singapore and one in the US. SGH had to turn to the US because the cord-blood bank in The research will include the evaluation of Singapore, which has only 1000 samples, could find only one close match. The import cost about US$20 medications and the development of psycho- 000. It costs Singapore about $1500 (US$820) to collect social strategies for the treatment of opiate, and process each lot of the blood, which is taken from cocaine, methamphetamine, alcohol and an umbilical cord soon after it is cut from a baby. nicotine abuse and dependence. The research In the US, adult patients have been given cord will be divided between the US and Thailand. blood for fatal blood disorders, but only after the removal of much of their bone marrow. But Prof. Tan said that Dr. Walter Ling is professor of psychiatry and removing bone marrow could be dangerous, as there is director of the Integrated Substance Abuse Program at a risk the cord blood will not produce new marrow. In the University of California at Los Angeles (UCLA), one such cases, a patient could die. of the foremost substance-abuse research groups in the Mr. Huang was given the cord blood on 12 world. December last year through a transfusion. It found its His work in opiate pharmacotherapy — the way into his marrow and slowly displaced his diseased treatment of disease with drugs — has provided pivotal cells. Signs the therapy was working came 22 days later. information for the approval of LAAM, naltrexone, and At present, 90 percent of his marrow had been replaced. buprenorphine. The other patient, Mr. Slamat Sampoerna, 40, from LAAM, or Levo-alpha-acetyl-methadol, is an Indonesia was given one lot of cord blood on 28 alternative to methadone therapy for individuals November 2001. It is taking much longer for his marrow addicted to opiates. Naltrexone is a drug prescribed to to be replaced. So far, more than 60 percent of it is from help people continue abstaining after detoxifying from the cord blood. heroin or other opiates. It has also been used as a With these two successes, Prof. Tan and his team treatment to support abstinence for people dependent are looking at treating more patients who have not on alcohol. Buprenorphine is a treatment for heroin and responded to conventional treatment. other opiate addictions.

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Research News Methadone, LAAM and naltrexone are approved by Other Countries the US Food and Drug Administration (FDA). Buprenorphine approval is expected soon, but it is already available in several European countries and Australia. US Scientists Develops These medications are the only treatments for heroin and opiate addictions approved by FDA, according to Dr. Device for Checking Ling. Blood Pressure in Heart “Pharmaceutical companies have shown little interest in developing medications for treatment of Having your heart checked in the future may be addiction because there is little money to be made. Most as easy as driving through a tollbooth. Researchers addicts are poor, and the market is small. As a result most are testing a small plastic chip designed to let doctors of the research on medication development for treatment measure blood pressure within the heart as well as of addiction in the US is supported by the federal major arteries. The device was originally developed government,” Dr. Ling explains. for use in jet engines by Dr. Mark Allen at the Georgia Institute of Technology. Dr. Allen describes the technology as being similar to electronic toll-collection “Pharmaceutical companies have shown little systems used on highways. interest in developing medications for treatment of addiction because there is little money to be Dr. Allen said that the unique philosophy of this particular device is to try to keep what is inside the made. Most addicts are poor, and the market is body as simple as possible and put all the complexity small,” Dr. Ling explains. in the readout that is outside the body. Soon this microchip may be available to monitor blood pressure In addition, his group conducts a wide range of inside the heart, giving doctors valuable treatment epidemiological and treatment outcome research in information. California and throughout the US. He and his group have been treating and conducting clinical research on Dr. Barry Katzen, medical director of the Miami methamphetamine addicts and addiction since the mid Cardiac and Vascular Institute, said that it is going to 1980s. essentially be like an early warning system in patients known to have significant problems. If the higher There has always been a “regional” metham- pressure can be detected earlier, then the medication phetamine problem on the west coast of the US, which can be adjusted and hopefully keep the patient out of has spread in recent years to the Midwest and other parts the hospital. of the country. The device works by threading a microchip, The problem has reached epidemic proportion in smaller than a dime and as thin as a piece of paper, many parts of the world, including Thailand. While there through a blood vessel and secured within the heart are considerable experience dealing with the problem or an artery, where it directly measures and then sends in the US, Dr. Ling said that there are differences from out the patient’s blood pressure information. region to region and country to country. That is why research in Thailand is important to establish a knowledge According to Dr. Katzen, the measurement could base for developing appropriate treatment strategies. be done on an outpatient basis in a fairly simple procedure with just a little local anesthesia. This tiny He said, “For example, methamphetamine-users in piece of plastic is the equivalent of transponders used Thailand are much younger, and we have to be concerned in cars for paying tolls automatically. about the neurotoxicity of the drug on their still developing brains, especially the long-term physical and Unlike the car transponder that sends the identity mental-health effects.” of the driver to the toll collector, this microchip sends the blood pressure in the patient to the doctor. He also explained, “However, as well as places having their own characteristics, drugs and of course The equivalent of the toll booth is a small methamphetamines in each region are different. That is handheld transmitter/receiver that provides power to why we are trying to figure it out first, before solving the the microchip and records the blood-pressure readings problem in Thailand.” from the embedded chip.

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Doctors are hoping to use the new technology in variety of illnesses including cancer and birth defects patients with aneurysms and congestive heart failure in their children. — two problems in which blood pressure is crucial. Dr. Karmaus used information from studies of men When an aneurysm, or weakening of an artery, is and women who liked to fish in the Great Lakes, which detected, doctors insert a fabric graft that replaces the are polluted with a range of chemicals. Their blood weakened area. levels of PCBs and other chemicals were measured. In some cases the grafts leak and cause a local The 101 families they studied had children born increase in pressure that can cause the artery to rupture. after 1963 and both mother and father had detectable By placing a microchip in the graft area, doctors will PCBs in their blood. There were a total of 208 children. know if the pressure is reaching dangerous levels and Of these, 57 percent were boys, which is a slight the patient is at risk of rupturing an artery. increase of the normal trend of about 51 percent. Usually, 105 boys are born for every 100 girls. The chip also may help congestive heart failure patients who suffer serious problems when pressure in However, Dr. Karmaus said that she did not detect the heart is too high. that the PCB levels of mothers affected the number of boys or girls. Writing in the January issue of the Journal Dr. Jay Yadav, director of vascular intervention for of Occupational and Environmental Medicine, Dr. the department of cardiovascular medicine at the Karmaus stressed that his sample was small. He noted Cleveland Clinic, said, “Currently, physicians treating that other studies had showed conflicting findings. patients with congestive heart failure are forced to go by the patient’s symptoms, or perform an invasive One study after a dioxin accident in Italy in 1976 procedure to obtain information about the pressures in found people who were exposed had more girls than the heart. In the future, this device may also be modified boys. Another was a study on army servicemen who to measure other properties within the body, such as were exposed to Agent Orange during the Vietnam war. blood glucose levels in diabetic patients.” They found fewer girls and more boys. PCBs can come from many different industrial sources including hydraulic fluids and oils, electrical capacitors and transformers. Men Carrying Pollutant PCBs Have More Boys Alternative Medicine China Men who have higher levels of polluting chemicals known as PCBs in their bodies are slightly more likely to father boys. The researchers at Michigan State University said that their study shows that human beings West Interested in Using can be affected sexually by the chemicals, which cause sex-related defects in animals. Chinese Ant to Boost Dr. Wilfried Karmaus, an epidemiologist who led Immune System the study, said, “A change in the proportion of boys to Scientific research in China has shown that a girls indicates that environmental contaminants may particular species of Chinese ant, the Polyrhachis Vicina, play a role in human reproduction.” increases longevity in rats. For centuries, this ant has PCBs are endocrine disrupters — chemicals that been prized by Chinese royalty and used in Tibet as a act like hormones. They and related chemicals known drink tonic to boost the immune system and relieve as dioxins are reported to have caused deformities of arthritis in people. sexual organs in fish and alligators. Dr. John Wilkinson, senior lecturer in In humans both dioxins and PCBs can cause cancer, Pharmacognosy at Middlesex University, is studying the infertility and perhaps other sexual changes. Vietnam properties of these insects. Dr. Wilkinson said that these veterans exposed to dioxin in Agent Orange, used to ants contain a lot of zinc and zinc has been identified strip foliage in the jungle, claimed that it has caused a for some time as an immune stimulant and an

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