Health Meaning

SAN FRANCISCO - The kidnapping and murder of 3 years Katie Lynn Lee could leave in 1993 a lasting legacy in law enforcement: the methods to obtain the fingerprints of children before they evaporate crime scenes and develop "profiles" chemical criminals. The results, reported here this week at the annual meeting of the American Chemical Society, may even lead to a new approach to disease diagnosis.

Police investigating the disappearance of Lee in Knoxville, Tennessee, failed to find evidence of his fingerprints despite witness accounts by placing it on the stage. Police have asked Michelle Buchanan, group leader for organic mass spectrometry to the US Department of Oak Ridge National Laboratory Energy in Tennessee to take a crack at solving the mystery.

team used gas chromatography Buchanan and mass spectrometry to compare chemicals fingertips of dozens of children aged 4 to 17 with those of adults aged 19 to 46. footprints digital kids, they found, quickly evaporated hot surfaces as they are loaded with volatile fatty acids. After puberty, however, the sebaceous glands begin to secrete heavier, alkyl esters, less volatile long chain that dust easily collected carbonaceous impression.

The Buchanan team identified some compounds, such as squalene, common to the fingerprints of children as well as adults. A detection system of unique fingerprints of these chemicals could be developed in 3-5 years, says Knoxville Detective Art Bohanan. "We have identified the problem, and now we need a solution," he said. Meanwhile, Bohanan said investigators should dust for fingerprints of children immediately at a crime scene and preserve key evidence under refrigeration.

the Buchanan team found a host of other ideas in body chemistry hidden in fingerprints. for example, they were able to measure cholesterol, nicotine and levels . hormone in fingerprints subjects "on the road, maybe the police will be able to say:" This footprint was left by a man of 34 who had smoked marijuana and had high cholesterol , "said a member of the Stephen Jarboe team from Transylvania University in Lexington, Kentucky. Buchanan said she hopes the results will encourage researchers to develop profiling systems criminals and diagnosis of diseases without surgery.

The researchers found that a diet high in salt causes subtle biochemical changes that can fatally shaking heart rate in rats with high blood pressure. The results, reported in tomorrow's issue of Science * suggest how untreated hypertension in people can lead to chronic heart failure.

Doctors have long thought that in a hypertensive person, the heart adapts to stress by expanding to pump blood more efficiently. Thinking such swelling may not be as benign, W. Jonathan Lederer and colleagues at the University of Maryland School of Medicine in Baltimore probed the mechanism by which the heart muscle cells to absorb calcium, which causes the heart to contract. They fed a high salt diet in a strain of rats bred to have high blood pressure, and analyzed changes in calcium channel moves into a cell to trigger contraction.

The researchers found that the differences between the calcium channels and calcium receptors located just inside the cell membrane had expanded. Initially, however, the rats have overcome this defect by producing additional adrenaline that the increased sensitivity of calcium receptors. But after several weeks of steady expansion, damaged hearts started to contract evil, resulting in heart failure.

Experts are impressed by the study. "What is surprising is that most of the problems seem to be a step between the electrical excitation of the heart and its contraction," says David Yue, a biomedical engineer at the School of the Johns Hopkins University of Medicine in Baltimore . Such a fundamental fatal process is also likely to occur in people, said Lederer. The message for people with high blood pressure, he said, is "Do not wait to treat, because you develop an irreversible failure." In the meantime, Lederer says, pharmaceutical companies should aim to test agents which increase the calcium receptor sensitivity in hypertensive people.

* for details, Science online subscribers can link to the full text of the report.

Researchers have finally been able to make charges stick against a tumor suppressor gene long suspected. The gene, called NF1 , was identified in 190 as the culprit in neurofibromatosis (NF), a disfiguring and potentially fatal disease that affects one in 3500.

in the number of tomorrow the New England Journal of Medicine , researchers from the University of California, San Francisco, and Roche Biomedical Laboratories report convincing evidence that NF1 gene acts as a suppressor tumor in human cancer. Such genes help regulate cell division, and when they are missing or inactivated by mutations, cell division is unleashed, causing tumors. The discovery suggests that therapies under development that target the pathway of cell division may hold great promise for NF1 patients who develop many non-cancerous tumors and have a very high risk for several types of Cancer.

Scientists already had tons of indirect evidence that NF1 was a tumor suppressor. The disease itself, with its multiple tumors, suggests the work of such a gene has gone wrong. And in a few months NF1 discovery of, the researchers found that its sequence was remarkably similar to a gene called GAP , which was known to regulate the signal system tells a cell to divide. Data from mice also suggested that the gene was necessary to prevent tumor development. But it has been difficult to gather strong evidence needed to confirm the role of tumor suppressor.

The best way to prove that a gene is a tumor suppressor is to show that the gene works properly in normal cells, but is absent or inactive in tumor cells. This has been difficult to prove to NF1 , because the large gene could potentially contain thousands of mutations that render inactive, and it is impossible to screen for all of them. But a tip recently developed to examine the protein product of the gene activated Kevin Shannon, a pediatric hematologist and oncologist at the University of California, San Francisco, and colleagues to gather evidence to load. They examined tissue samples of 18 children with NF who also developed leukemia. In eight patients, the normal cells showed mutated NF1 gene and a normal gene, while cancer cells had only the mutated form. "Overwhelming evidence," said Shannon, the NF1 gene is indeed the culprit in cancers.

Other researchers applaud the work. "This is the best example NF1 is a tumor suppressor, "says David Viskochil, a geneticist at the University of Utah, but he warned that the case is not yet closed: There may be still other genes that play a role in tumor development NF. Nevertheless, he says, the finding suggests that drugs that block the path to cell division will be an effective treatment for NF leukemia related and potentially other disease complications.

W ASHINGTON , DC - New therapies and treatments for diseases are compromised by a decline money, time, and training for clinical research, scientists said today at a joint meeting convened by the Institute of Medicine (IOM). Gaps in Clinical Research "will compromise our ability to bring innovation to health care at the bedside," warned Kenneth Shine, IOM President.

Most clinical research is performed in hospitals managed by medical schools. But the rise of managed care, such as health maintenance organizations (HMO), requires training and research hospitals to cut costs and competition. This "irrevocable rapid momentum to control costs ... is rapidly squeezing the time and money of clinical research, "George Lundberg, editor of the Journal of the American Medical Association ( JAMA ), at a press conference.

As evidence of this trend, Lundberg said a report JAMA published today that details how the cost reduction takes a toll on clinical research. a study of 50 university hospitals by Eric Campbell of Massachusetts General Hospital and colleagues, clinical researchers based at hospitals in more competitive markets (defined in part by numerous, large HMO) published on average, 15% fewer articles in peer-reviewed journals that had peers in less competitive markets. Campbell also found that faculty members in competitive hospitals reported more patient care duties and stress department that made them less competitive their colleagues.

To reverse the decline today called Shine a 1% tax on health care premiums and self-insurance plans to support clinical research. Gradually over several years, service estimates the tax could raise up to $ 5 billion per year that could be allocated in the form of peer-reviewed grants.

A vaccine that AIDS has had more success in monkey experiments that any other approach has never been tested in humans. The reason: Many researchers believe the vaccine based on weakened - or attenuated - live virus, would be too risky.

The International based in Chicago Now, a group of doctors involved in AIDS care, convinced that the potential benefits outweigh the risks, leads an unusual campaign to recruit hundreds of volunteers for a study this security approach. Association of Physicians in AIDS Care (IAPAC) uses a live attenuated HIV test in the August issue of his newspaper and posted a registration form for the trial on its website (www.iapac.org) . IAPAC said more than a dozen people have already stepped forward.

Ronald Desrosiers, Central New England Regional Primate Research in Southborough, Massachusetts, first showed the power of live attenuated approach in a monkey study published in science there are nearly 5 years (December 18, 1992, p. 1938). Monkeys who received the vaccine are infected later, when administered a lethal strain of SIV, simian cousin of HIV. Desrosiers has spent the last few years to eliminate various genes of SIV and HIV to find a weakened form that is as safe as possible, but still be able to protect animals against pathogenic isolates of the virus.

A live attenuated vaccine AIDS would have three potential pitfalls, however. The weakened virus is still able to replicate and can cause AIDS after, say, 30 years. It is also possible that the virus could mutate into a virulent form, although Desrosiers think that this risk can be virtually eliminated by removing enough genes. Finally, the weakened HIV would still incorporate the DNA of a host cell, which could theoretically trigger cancer.

Leading the drive to register is voluntary AIDS clinician Charles Farthing, medical director of the AIDS Healthcare Foundation in Los Angeles, California. Farthing said he hopes the trial will show that people, like monkeys, can control the replication of the virus and weakened immune comes to no harm. Yet AIDS experts say a short trial would not answer some key questions of security. "We are really concerned about what happens when you vaccinate 20 million people and 10 years later, 5% or 10% get lymphoma," said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases. "You're not going to know [IAPAC's proposed test]."

A team of researchers immunized mice with proteins derived from their own cancer cells. The treatment, reported in tomorrow Science *, significantly slowed the spread of many types of cancer.

A group of researchers from the University of Connecticut School of Medicine in Farmington made the vaccine by purifying heat shock proteins (HSP), which are released from stressed cells and alert the immune system to destroy it. To test the ability of the vaccine to stop the spread of cancer, the researchers injected cancerous lung cells in the footpads of mice. The tumors were removed when they were 5 mm wide, and half the mice received weekly doses of heat shock proteins purified from the same type of cancer cells that were injected. The mice that received saline all died within 45 days of cancer that spread from tiny remnants of the tumor. But 80% of vaccinated mice survived without cancer lesions for 250 days. The team had similar success with colon cancer and melanoma.

"We proved the HSP vaccines can be used as a general strategy for treating a variety of tumors in mice," said Ping Peng, an immunologist with the team. Research is an important step, says Hans Schreiber, an immunologist and cancer researcher at the University of Chicago. By purifying the heat shock proteins of cancers, "you can get individualized therapies," he said. "This is a major breakthrough."

* For details, Science Online Subscribers can create a link to the full report.

W ASHINGTON DC - After decades of largely be repelled by the American medical establishment, acupuncture appears to be gaining some respectability. Last year, the Food and Drug Administration took the label off of acupuncture needles "experimental" as medical devices. And today, a group of experts convened by the National Institutes of Health (NIH) concluded that acupuncture is an effective treatment for nausea and some forms of pain.

About 1 million people get stuck in the United States each year, mostly for pain relief, the panel said. Some Western researchers say acupuncture triggers the production of many chemicals, including endorphins analgesics, benzodiazepines endogenous painkillers and serotonin with mood lifting. "The challenge in studying acupuncture is to integrate the theory of Chinese medicine in the classic model of Western biomedical research," says the president of the committee David Ramsay, president of the University of Maryland.

The conference, sponsored by the NIH Office of Alternative Medicine (OAM), reviewed research on a host of ailments: nausea and ovulatory problems to paralysis and drug abuse. Although research that most acupuncture studies are lacking for various reasons such as covering too few subjects or lack of control, the panel found "clear evidence" that the acupuncture needle can relieve nausea of operations and chemotherapy, and perhaps morning sickness. They also found "evidence of effectiveness" for postoperative dental pain, and "reasonable studies" showing the pain for other conditions

to penetrate deeper into the mystique of acupuncture, the panel called for more research. - the music to ears of OAM, who sponsored $ 2 million for research on acupuncture in the last 5 years. especially gray areas, the Panel noted include discrimination "reality" from acupuncture points "dummy" for research purposes.

But experts are not invited to address the panel say that there is less mystery than meets the eye. Longtime acupuncture practitioner George Ulett, psychiatrist and neurologist at the Institute of Mental Health of Missouri in St. Louis, said you can forget the Yin and Yang: Electrical stimulation - either with needles or conductive pads - is "a very simple technique" to fan the hormones that affect the nerves.

W ASHINGTON , DC - Scientists have discovered a gene that some cancer cells destined to a period of limited life. Experts hope that the finding, reported this week at the American Society for the Annual Meeting of Cell Biology, could eventually lead to a new type of gene therapy for cancer.

Most adult human cells are at rest, meaning they stopped dividing, after receiving certain biochemical signals. But even without these signals, most cells will eventually stop dividing themselves, to achieve a permanent sort of quiescence called "senescence". signals cancer cells to ignore becoming idle, and many types never reach senescence. They are called immortal, because, in theory, they could continue to divide forever.

By using a careful combination of trial and error and standard genetic techniques, gerontologist Olivia Pereira-Smith and colleagues at Baylor College of Medicine Houston, Texas, have now found a gene that ends in immortality one of the four classes of immortal cells. They used cell lines of brain cancer and cervical cancer. Based on its sequence, the group says the gene may encode a transcription factor, a protein that controls the expression of other genes -. Perhaps those that give the cells of limited life

The conclusion "will give us insight into the entire process of [cellular] immortality," says Harvey Ozer, a molecular biologist and cell at the New Jersey medical school in Newark, because this is the first time that researchers have found a gene involved in the process. the gene could one day be used to treat cancer, Ozer said. "If you should find a way of introducing a normal version of this [gene] in [patient's] cancer cell, you might stop growing. "

P HILADELPHIA - A molecule known for its Texas circumference now appears to be a promising new weapon against cancer . A pilot test of the new metal compound carrying heavy, described here Saturday at the annual meeting of the American Association for the Advancement of Science (which publishes Science NOW), extended the life of people living with brain cancer.

natural pigments called porphyrins, that carry iron in the blood, the home in on the tumors. Jonathan Sessler, a chemist at the University of Texas, Austin, thought that porphyrins could become haul for cancer drugs. Because Sessler said that everything is bigger in Texas, he initially stalled fifth link in the porphyrin molecule, resembling a bracelet of four linked rings. This new molecule "Texas size" - appropriately nicknamed texaphyrin - had a capacity of 20% larger, enough to carry a heavy metal atom of gadolinium. net positive charge of gadolinium would be able to absorb an excess of electrons, which tend to recombine with hydroxyl radicals - corrosive molecules formed during radiation therapy against tumor - and eliminate their carcinogenic killing. Gadolinium, Sessler hoped would prolong the effects of hydroxyl radical and thus increase the power of radiation.

To see if Texaphyrins gravitate to tumors like their cousins ​​are porphyrin, Sessler used magnetic resonance imaging (MRI) to scan cancerous mice before and after an injection of texaphyrin. Gadolinium MRI shows increased sharply. Sessler and colleagues at Pharmacyclics in Sunnyvale, California, found that cancerous cells appeared bright white areas on the MRI, even days after an injection of texaphyrin. When the team irradiated these mice, tumor cells decreased or disappeared and 50% of the mice survived the 140 day study. Only 10% of irradiated mice survived without texaphyrins.

In early clinical trials, Sessler and colleagues treated 39 patients with metastatic brain tumors with Texaphyrins 2 hours before radiotherapy for 10 days. Patients who had a life expectancy of 2 to 4 months, survived an average of 188 days. The patients in the group receiving the highest dose survived an average of 362 days. Although drug studies are not complete, Sessler said, "there are people alive that would normally be dead." The National Cancer Institute has selected Texaphyrins within its network of decision NCI -. A group of what he considers therapies is coming and most promising

In one of the greatest moments in modern medical science, American microbiologist Jonas Salk, April 12, 1955 delivered safely its vaccine against polio newly invented and effective in almost 0% of cases. Salk discovered that injecting a small amount of killed virus induces the body to produce protective antibodies without causing polio, a disease that caused permanent paralysis, particularly in children, since the time of the Ancient Egypt.

Salk identified the three main varieties of poliovirus, developed a killed virus vaccine tested in monkeys and in May 1952 conducted a test on the massive human terrain of over 400,000 children - the most largest medical experiment ever conducted in the United States. After the success was proclaimed in 1955, the Salk vaccine against polio was administered to more than 0 million people in the United States, and the incidence of polio has dropped from 96% in 1961. Salk vaccine finally was replaced by a more effective live oral vaccine developed by Albert Sabin competitor and distributed worldwide. Some 2,000 cases of polio were reported last year, most of which were in the Indian subcontinent and the former Soviet Union

[Source:EmilyMcMurrayEd Notable Twentieth Century scientists (Gale Research Inc., ITP, 1995).]