Exercise your brain


ew light has been shed on the well-known antidepressant effect of exercise by a pilot study reported in the British Journal of Sports Medicine. It was suspected that an endrophin-like substance, phenylethylamine, might be responsible for the well-being associated with as little as four hours of exercise weekly. On non-exercising days, urine samples were tested for phenylacetic acid, a by-product of phenylethylamine turnover. Urine samples were again collected after treadmill exercise in which heart rate had climbed to at least 70% of maximal heart rate capacity, a level thought to be capable of changing mood. Phenylacetic acid levels increased by ~ 77% after exercise. However, the rise in levels varied widely across the group tested, with maximal increases seen in those subjects who rated the exercise as difficult. The authors believe that many factors might be involved in the phenylacetic acid response to exercise but, considering that the chemical structure of phenylethylamine is very similar to that of amphetamines, this chemical might be part of a ‘runner’s high,’ a phenomenon linked to natural endorphin activity in the brain.


November 11 , 2001 TRENDS in Biochemical Sciences Vol. 26 No. 11


Beauty in chemical


 chemical involved in immune system signalling may be able to reverse some types of skin damage caused by sunlight. It could reduce sunburn by activating DNA-repair mechanisms, suggests a new study by researchers from Germany-based  University of Munster. This finding raises the possibility that the chemical might be used to prevent or treat skin cancer. The researchers found that IL-12 promotes repair rather than blocking ultraviolet rays, as most sunscreens do.


December 31, 2023 Down To Earth

 Injecting a cure


ith the help of a chemical, diabetes sufferer with early symptoms could be prevented from developing the disease completely, research has suggested. Trials found that a specific peptide- a substance formed from amino acids- halted the progression of Type1 diabetes (the insulin-dependent form that must be treated with injections) in humans and mice. Jerusalem- based Hadassah-Hebrew University Medical school and Peptor Limited, a pharmaceutical company also based in Israel, conducted the research. It is hoped that the discovery could lead to the development of new life-saving drugs.


December 31, 2023 Down To Earth


Bacteria modify the negative approach


ipid A constitutes much of the outer lipid coat of disease-causing Gram negative organisms such as Escherichia coli, Salmonella and Pseudomonas. A novel method of bacterial resistance has been identified, by which an unusual sugar, aminoarabinose, is attached to the lipid, with the overall effect of reducing the net negative charge of the bacterial coat. Antibiotics (e.g. polymyxin) attach to the bacterial lipid coat via positively charged groups, the interactions of which are lessened with weakened negativity of the aminoarabinose-coated lipid. Duke University Medical Center biochemist Christian Raetz (Durham, NC, USA) said, ‘…we have discovered the enzyme that attaches this modifying group to lipid A, as well as a novel precursor molecule (named undecaprenyl phosphate-aminoarabinose) that donates this aminoarabinose to lipid A. It might be possible to redesign peptide antibiotics to work even against bacteria with aminoarabinose attached to their lipid A. …Also, one could imagine devising inhibitors of our aminoarabinose transferase enzyme that would render polymyxin resistant mutants sensitive again.’ The transferase enzyme was pinpointed by genetically analysing a polymixin-resistant strain of Salmonella (the arn T gene codes for the protein responsible for transferring aminoarabinose to lipid A). A similar gene to arn T has been identified in resistant strains of E. coli. In future studies, the scientists will trace the full metabolic pathway, which could yield additional enzyme targets for inhibitory drugs. These finding are being published in the Journal of Biological Chemistry.


November 11, 2023 TRENDS in Biochemical Sciences Vol. 26 No. 11

Spinach can cure certain forms of blindness


pinach, the vegetable loved by Popeye, could prove to be a remedy for certain forms of blindness. Doctors now believe that an eyedrops containing a protein taken from spinach could be soon available to treat the millions of people suffering from age-related macular degeneration of the eye and retinitis pigmentosa.
            Age-related macular degeneration is a common eye disease associated with ageing that gradually destroys sharp central vision. The macula is made up of millions of light-sensing cells in the middle of the retina. When these cells degenerate, vision is impaired and if the disease progresses quickly, blindness follows. Retinitis pigmentosais a genetic disease which affect about one person in 4,000. Sufferers develop night blindness, then tunnel vision and finally lose their colour and day vision.

  December 2001  Health Action   

Cancer in the air


iving in an environment polluted with even low levels of benzene can cause cancer. While exposure to benzene at work place have been known to cause cancer, a study published recently in the American Journal of Epidemiology shows that exposure to low concentrations of the chemical such as those present in vehicular emissions can also cause cancer.
            Researchers from the Danish Cancer Society and the National Environmental Research Institute, Denmark, found that children exposed to traffic-related air pollution had more chances of being affected by lymphomas, a cancer of the lymphatic system characterized by enlargement of the lymph nodes and glands. The researchers studied 1989 cases of children suffering from leukemia, tumour of the central nervous system and malignant lymphoma that were registered in the Danish Cancer Registry during 1968-1991. The histories were compared with the medical records of 5,506 healthy children selected at random. They then collected the residential history of all these children starting from the time they were conceived till the time the disease was diagnosed. The information was used to assess the amount of vehicular pollution they were exposed to. They also took into consideration other potential causes of cancer such as exposure to electromagnetic radiation, mother’s age at conception and level of urbanization.
            They found that the risk of Hodgkin’s lymphoma increased by 25 per cent when the amount of benzene in the air was doubled during pregnancy. Similarly, the risk increased by 51 per cent when the nitrogen dioxide emissions present in the air doubled.
            “This is a suggestive observation that will require conformation,” says Lucy M Anderson of the National Cancer Institute, USA. Even Ole Raaschou-Nielson, one of the research team member, agrees. “We cannot rule out the fact that they might be numerous other factors which can be the culprits,” says Raaschou-Nielson.

 December 15, 2001, Down To Earth


Concern raised for missing biologist


tructural biologist are in shock following the disappearance of Don Wiley, one of the leading figures in the field. As Nature went to press, more than a week after Wiley’s car was found abandoned near Memphis on a bridge over the Mississippi river, the FBI was still investigating.
            A professor of biochemistry and biophysics at Harvard University, Wiley has been seen as a candidate for Nobel prize. He won a 1995 Lasker award for this resolution of the structure of the two classes of major histocompatibility proteins. These proteins bind to foreign proteins, altering the immune system to mount a response. Wiley’s work opened up new vistas in immunology.
            His other key work has been on the haemagglutinin protein of the influenza virus. Wiley’s analyses led to understanding of how the virus fuses with host-cell membranes. His further work on other viruses suggests the mechanism may be general.
            Wiley was last seen leaving a dinner following a meeting of the scientific advisory board of St Jude Children’s Research Hospital in Memphis, where he is said to have been in good spirit.

 November 29, 2023 NATURE Vol. 414

Sweet news for diabetics 


re you a diabetic? And, insulin’s your life savior? Then here’s a herb that promises to solve all your problems. Paneerdatta, a flower is crushed gently to form small beads, dissolved in a cup of water for 12 hours, filtered and the water then drunk. Doctors say that if this is done for one month, it will ensure that diabetes is controlled. They also say that a patient may even discontinue medicines completely after about three months of regular intake with this potion.
            “Details of this are not being given out simply because plans are afoot to patent this findings,” says Dr. O. P. Saxena , Head of Department of Botany, Gujarat University.

 December 2001, Health Action


First human clones get a cool response   


n 25th November, Advanced Cell Technology (ACT) of Worcester, Massachusetts, announced that it had created a cloned human embryo. It claimed this as an important step towards the goal of therapeutic cloning-in which cloned embryos would be used to harvest embryonic stem (ES) cells to grow replacement tissues perfectly matched to individual patients.
      The ACT team fused adult cumulus cells – ovarian cells that surround eggs after ovulation – with  human eggs that had been stripped of their own chromosomes.
      In a press release, the company said that the paper provides “the first proof that reprogrammed human cells can supply tissue”.
      The ACT clones are “nowhere near” that stage, says Alan Colman.
Colman also notes that the development of ACT’s embryos compares unfavourably with experiments in animals. “Clearly, just extrapolating from the cow system into the human has not worked very well”, he says. “With cows you could expect over 30% of the reconstructed eggs to go to the blastocyst stage”.
      Jose Cibelli, ACT’s vice-president of research and the paper’s lead author, agrees the work is at an early stage but argues that it is still of interest: “We understand that these are early and preliminary results, but given the importance of this emerging field of medicine we decided to publish our results now”.
      While scientist debate the significance of ACT’s finding, political opponents of cloning are attempting to outlaw the research. The US Senate is considering a bill, already passed by the House of Representative, that would ban all forms of human cloning, both reproductive and therapeutic. Observers now expect this to be passed, and to be signed into law by President George W. Bush.

 November 29, 2001 NATURE Vol. 414




 range of internet enabled software tools that will help control the spread of the anopheles mosquito-the vector for malaria and filariasis – have been developed by scientists at the bio-informatics division of Indian Institute, said the user-friendly programmes developed by them will help forecast the onset of the disease and enable pro-active measures by public health officials based on the data collected  and fed into the computer.

 December 15, 2023 Down To Earth


US warning on obesity


ome 300,000 Americans a year die from illnesses caused or worsened by obesity, a toll that may soon overtake tobacco as the chief cause of preventable deaths, Dr. David Satcher, the surgeon general , said on Friday. Dr. Satcher called for major steps by schools, communities and industry to fight obesity.
          “We’re not talking about quick-fix diets,” Dr Satcher said.
“We’re talking about lifestyles.”
          About 60 per cent of adults are overweight or obese, as are nearly 13 per cent children. According to the surgeon general’s height and weight index, a 5-foot-6 adult is overweight at 160 pounds and obese at 190. The toll of obesity has been rising and threatens to wipe out progress fighting cancer, heart disease and other ailments, Dr Satcher warned.
          The reason is not a mystery: People eat more calories – often by shunning fruits and vegetables in favor of super-size junk foods-than they work off. Losing even 10 pounds can reduce the risk of getting diabetes or heart disease, Dr. Satcher said, as can walking 30 minutes a day.

 December 15, 2001, Hindustan Times


New Danger


 Swiss  study reveals that eating food cooked in a microwave oven may produce abnormal changes in human blood, cell and the immune system suggestive of conditions of cancer.
         Curiously, the study conducted as early as 1989 has come to light only recently. The reason: Swiss courts, under pressure from microwave oven manufacturers, had reportedly suppressed research by Swiss biologist, Dr. Hans Ulrich-Hertel. The biologist evidence has been published in the journal What Doctors Don’t Tell You.
          Russian  studies indicate that microwaving meat, milk, cereals and thawing fruits and vegetables produce carcinogens. Those consuming microwaved foods have showed a higher incidence of stomach and intestinal cancers.
          The US Food and Drug Administration’s (FDA) Centre for Devices and Radiological Health (CDRH), however, maintains that microwave oven cannot make food radioactive or contaminated and cooking in them does not reduce the nutritional value of foods.
           In the US, all microwave ovens made after 1971 are covered by a radiation safety standard enforced by the US FDA.
           The major health and safety concerns about microwave ovens are:
i)           Leakage of dangerous microwaves resulting in exposure to radiation and risk of cancer. Microwave radiation is odourless and invisible, making it hard to detect. Other health hazards of exposure to microwave radiation are cataracts, temporary sterility and mental impairment.
ii)          Fires and burns due to overheating /superheating and exploding foods and drinks.
iii)        The belief and microwave cooking destroys nutrients.
iv)        Cooking in microwave oven does not kill harmful bacteria.

October 2001, Health Action




Women close gap but it’s still a man’s world


ashington female scientists have increased their representation in the US scientific community, but still lag behind their male colleagues in attending full-time, tenure-track positions, according to a report by the US National Academic of Sciences. Women had almost no representation in the community 25 years ago, but in 1995 they accounted around a third of new a science PhDs and academic faculty in many fields, though there is wide variation.
            In engineering just 7% of degrees and 5% of PhD-level jobs in 1995 went to women, whereas in the biological sciences female scientists were awarded 50% of all undergraduate degree and 40% of all PhDs.

 November 22,. 2001 NATURE Vol. 414



Alternative medicine has bright prospectus


esides traditional medicinal systems, alternative medicine would have bright prospectus in the coming year, founder and chairman of Dhyanamandali (Vijayawada) C. Bhikshamaiah guruji predicted on Monday.
            Addressing a press conference after being awarded with ‘Star of Millennium’ by the National council of Alternative Medicine recently. Bikshmaiah said that amalgamation of meditation with radionics therapy was proving good for curing chronic disease.
            Stating that Reiki, pranic healing, oil pulling, acupressure, acupuncture, magnetotherapy, radiation technology, aroma therapy and naturopathy were some of the alternative medicinal systems available across, the world, he observed that all the disease were psychosomatic. Insomnia, depression and stress were responsible for the occurrence of the disease in a person.
            To cure chronic disease like a diabetes and arthritis, Dhyanamandali has been adopting a procedure called ‘Multiyoga therapy treatment’ by integrating available alternative medicine systems, he added.

 January 2001, Health Action



Reduce stress to tame that flab


isruptions in the human nervous system, or stress, can concentrate fat around the abdomen, raising the risk of diabetes as well as heart problems, a study by the university hospital in the Swedish city of Gothenburg found.
      “ The stress system has developed to deal with periods of brief stress for stone–age man preparing for battle or flight. But in today’s civilized world, stress is different. One does not beat up the boss or run away from the mortgage institute, “ said physician Thoman Ljung, who led the study.
         Researchers have found that fat plays an important role in protecting bones and organs, regulating hormones and the immune system and managing women’s reproductive systems. Fat produces an important hormone called leptin that communicates with the brain, informing it how the body’s energy levels are doing.
        Simon Coppack, a researcher at the St Bartholomew’s and the Royal Londan School of Medicine and dentistry said: “Fat is an organ. You should probably think of it as a little bit like the liver” the hormone tells the brain when the body needs to eat and when it has eaten too much. It also plays a role in the reproduction process. Women with very little body fat, such as anorexics, do not have periods. Simon Coppack said body fat can contribute to a healthy pregnancy. “If you went into a pregnancy malnourished, that would be catastrophic for both baby and mother”, he says.

 February 2002, Health Action



Ten medical school in US take to Ayurveda


yurveda the ancient Indian system of medicine, will be taught as a short-accredited course in ten US medical schools by the end of 2002.
      Measures to popularize Ayurveda was discussed recently by Indian Health Secretary Shailaja Chandra and Joana Rosario, Director, National Centre for Complementary and Alternative medicine, Maryland, U.S.
      The Ayurveda course will be taught under the auspices of the National Institute of Health in Maryland.
       Teachers of Ayurveda system of medicine in India will be sponsored by their government to visit the Us in January 2002 and present model of the accredited course in Ayurveda at the NIH.
      According to the recent deliberations, ayurvedic and herbal medicine would be introduced and promoted in the US where alternative medicine has a big $27, billion market.
       “A lot of research carried out in the West has proved Ayurveda to be effective in finding a cure for certain psychiatric diseases, arthritis, Alzheimer’s, diabetes, dysentery and skin ailments.” Said Navin Shah, a noted urologist of Mary land. Herbal medicines, he said, are becoming very popular in the US because allopathic drugs are expensive and have several side-effects.

 February 2002, Health Action



New anthrax medicine


cientist in India have created a new vaccine for anthrax, which they say could be less toxic and more effective than the one that is currently available. The alternative has been developed by a team from the Centre for Biotechnology at the New Delhi-based Jawaharlal Nehru University. It is made up of harmless mutant forms of three key proteins that together make the toxin that does the damage to humans. Rakesh Bhatnagar, who led the research team, says the laboratory testing of the new vaccine has been completed and it would now be subjected to animal and human trials.

 December 15, 2023 Down To Earth


 Garlic, remedy for cold


arlic can help alleviate the misery of the common cold, say scientists who discovered an active ingredient in the plant which reduces symptoms like sneezing, coughing and a runny nose and speeds up recovery. The substance also slashes the chance of being re-infected with a new cold by boosting the immune system. Writing in the journal Advances in Therapy,  the researcher say allicin, a compound from the garlic bulb known to fight bacteria, may be a ‘cure’ for the debilitating common cold.

 December 2001, Health Action  


Nuclear receptor has a role in wound healing


wiss researchers have uncovered a protein involved in the response to skin injury that helps elucidate the molecular mechanism and genetics of wound healing, and might lead to identification of targets for the development of new treatments for skin disorders.
            Walter Wahli and colleagues had previously found that a nuclear receptor protein, peroxisome proliferator-activated receptor b (PPARb), is a critical gene regulator in the cellular response to inflammation, and in differentiation and migration of keratinocytes in the epidermis.
            It has been demonstrated that the stimulation of the PPARb gene and then the activation of the PPARb  protein are required in wound healing thereby suggesting that healing defects may arise from a lack of PPAR gene expression, or a default in PPAR protein activation, or both combined”, says Wahli. The investigators also suspect that PPARb dysfunction could be one of the molecular mechanism underlying psoriasis, since keratinocyte differentiation induced by inflammation is impaired in psoriasis.
         Wahli suggests that drug therapies could be developed that accelerate the healing of surgical wounds and diabetic ulcers by inducing the PPARb gene or activating the PPARb protein. Drugs could also be designed to inhibit PPARb gene expression and PPARB protein  activity to address diseases with an underlying overexpression of PPARb. Further  research will hopefully identify the genes targeted by PPARb and explain how this mechanism might apply to other tissue in which PPARb is expressed.
       Theodora Mauro (University of California at San Francisco, CA, USA) is more sceptical about the findings. “A previous study using a PPARb activator improved psoriasis by decreasing keratinocyte differentiation, suggesting that this receptor stimulates differentiation, not proliferation”. Unfortunately, says Mauro, the proliferation of keratinocytes is necessary, at least in the early stages of the wound repair. She also asks whether PPARb  could function in wound healing without PPARa “It seems as if many of the functions ascribed to PPARb [anti-inflammatory, pre-differentiative] would hinder not help wound healing, and that PPARa may be directing the timing of PPARb activities for later in the wound healing process”, she says.

 December 15,2023 The Lancet Vol. 358



Raised triglyceride concentration is an independent risk for stroke


esearchers in Israel report this week that a high blood triglyceride concentration is an independent predictor of stroke in people with coronary heart disease (CHD). “This is the first large study to provide strong evidence that elevated blood triglyceride levels, independent of cholesterol levels and its fractions, can predict the occurrence of stroke among patients already suffering from heart disease”, asserts lead researcher David Tanne.
       Tanne and colleagues followed-up 11 177 people who had CHD, but no history of stroke or transient ischaemic attack (TIA), for 6-8 years. Of the 941 individuals who developed cerebrovascular disease during follow-up, 487 had a verified ischaemic stroke or TIA (circulation 2001; 104: 2892-97). “We found that those with high blood triglycerides [> 200 mg/dL] have a nearly 30-50% higher risk of suffering an ischaemic attack or TIA, after controlling for well established risk factors for stroke such as high blood pressure, cigarette smoking, or diabetes”, Tanne told The Lancet. The researchers also found that people who had a stroke also had lower concentrations of high-density lipoprotein (HDL) cholesterol.
        “This is well-conducted study that sheds new light on the relationship of lipids and stroke”, comments Ralph Sacco (Neurological Institute, New York, NY, USA). “Unlike heart disease, the relationship between stroke and cholesterol has not been as clear. New data such as this study provide a stronger link between stroke and lipids.”
          Sacco, who has previously shown that HDL cholesterol is a protective factor for stroke in elderly people, suggests that clinicians need to focus more on the control of lipids as an important modifiable risk factors for stroke.
         Tanne agrees with this view and suggests that clinicians should  measure triglyceride concentrations as part of their global risk factor assessment of stroke in all individuals. “Although measured as part of a lipid profile, triglycerides are not given sufficient attention for stroke prevention by practitioners. Triglyceride concentrations may help to refine the risk of ischaemic stroke.”
          Tanne stresses, however, that further studies are needed to determine whether there is a similar relation between triglyceride concentrations and stroke in people without CHD, and also whether lipid-lowering drugs or drug combinations can help prevent stroke in patients with raised triglyceride concentrations.

December 15, 2023 
The Lancet Vol. 358



COX 2 inhibitors may increase risk of heart attack    


reatment with certain COX 2 inhibitors, non-steroidal anti-inflammatory drug that relieve the pain associated with arthritis, may increase the risk of heart attack according to a retrospective analysis of two separate marketing studies.
            The research comes within weeks of the National Institute for Clinical Excellence approving these types of drug for use in the NHS in England and Wales. The institute acknowledgement in a recent technology appraisal guidance bulletin that there is a such a risk and that COX 2 inhibitors should not be prescribed routinely to patients with cardiovascular disease.
            Researchers from the Cleveland Clinic Foundation in Ohio analyzed the cardiovascular event rates in two randomized multicentre trials. They also looked at myocardial infarction rates in the placebo group (23407 patients) in a meta-analysis of four large aspirin studies.
            They found that the annual myocardial infarction rate in the aspirin placebo group was 0.52%. This compared with 0.74% (P=0.04) for the COX 2 inhibitor rofecoxib (Vioxx) in the Vioxx gastrointestinal outcomes research (VIGOR) study and 0.80% for the inhibitor celecoxib (Celebrex) in the celecoxib long term arthritis safety study (CLASS).
            Aspirin use was not permitted in the VIGOR study, in which 8076 patients were randomized to receive rofecoxib 50mg a day or naproxen 1000 mg a day. There were 111 cardiovascular events in the rofecoxib arm and 50 events in the naproxen  arm.

September 1, 2023 BMJ.  Vol. 323