Archive for the ‘Medicine’ Category

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Almonds help fight viruses – but don’t peel them!

November 2, 2010
Shelled (right) and unshelled (left) almonds

Shelled and unsheld almonds: Image via Wikipedia

I love almonds anyway but I note that this research is funded by the Almond Board of California. I cannot help wondering what negative effects of eating almonds have been observed but will never be reported.

The Telegraph:

Researchers found almond skins improved the ability of the white blood cells to detect viruses while also increasing the body’s ability to prevent viruses from replicating and so spreading inside the body. They discovered that even after the almonds had been digested in the gut, there was still an increase in the immune system’s defence against viruses.

The scientists, who are based at the Institute of Food Research in Norwich and the Policlinico Universitario in Messina, Italy, said their findings suggest that the nuts can increase the immune system’s ability to fight off a wide range of viruses, including those that cause flu and the common cold.

Dr Giuseppina Mandalari, from the Institute of Food Research, said: “Almond skins are able to stimulate the immune response and thus contribute to an antiviral immune defence.”

The researchers, whose work is published in the scientific journal Immunology Letters and was funded by the Almond Board of California, found that even after digestion in a laboratory simulation of a human gut, the almonds skins were still able to increase the immune response.

They tested the immune response to infection by the Herpes Simplex Virus 2, which can cause cold sores and is a notoriously difficult virus to treat due to its ability to evade the immune system by dampening down the body’s inflammatory response.

They found that almond skin extracts were effective against even this virus.

But they found that almond skins that had been removed through blanching in boiling water, which is common process to remove skins from almonds, had little effect on the immune system.

The researchers say they are still to identify exactly what it is in almond skins that cause the antiviral activity, but they believe it could be due to compounds known as polyphenols.

It is thought they increase the sensitivity of white blood cells known as helper T cells, which are involved in fighting off viruses. They said it was likely that other nuts may also have this sort of activity.

Dr Martin Wickham, who was also involved in the study at the Institute of Food Research, said: “It is an area of huge interest to find natural alternatives that will have an antiviral activity. Nutritional guidelines recommend eating around three ounces a day to benefit from the fibre and other nutritional components in almonds, but we have still to do the work to see whether this would be enough to have an antiviral affect. This was just an initial study to find out if almond skins have this antiviral activity. The herpes simplex virus is a very good model of viral infection because it is known to evade the immune system, so because the almonds had an impact on this virus, it is fair to assume that it will have an impact on other viruses.”

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A special gene for camouflage

November 1, 2010

C. Zhang, Y. Song, D. A. Thompson, M. A. Madonna, G. L. Millhauser, S. Toro, Z. Varga, M. Westerfield, J. Gamse, W. Chen, R. D. Cone. Inaugural Article: Pineal-specific agouti protein regulates teleost background adaptation. Proceedings of the National Academy of Sciences, 2010; DOI: 10.1073/pnas.1014941107

Science Daily

 

Like other bony fish, the peacock flounder can change the color and pattern of its skin to blend into the sea floor. (Credit: Photo by Jimmie Mack)

 

Researchers led by Vanderbilt’s Dr. Roger Cone have discovered a new member of a gene family that has powerful influences on pigmentation and the regulation of body weight.

The gene is the third member of theagouti family. Two agouti genes have been identified previously in humans. One helps determine skin and hair color, and the other may play an important role in obesity and diabetes. The new gene, called agrp2, has been found exclusively in bony fish, including zebrafish, trout and salmon. The protein it encodes enables fish to change color dramatically to match their surroundings, the researchers report this week in the early edition of theProceedings of the National Academy of Sciences (PNAS).

“When my graduate student, Youngsup Song, discovered a third agouti protein in the fish pineal gland, an organ that regulates daily rhythms in response to light, we initially thought we had found the pathway that regulates hunger diurnally,” said Cone, chair of the Department of Molecular Physiology & Biophysics and director of the Vanderbilt Institute for Obesity and Metabolism.

“That is the mechanism that makes you hungry during the day, but not at night,” he continued. “However, Chao Zhang, a graduate student who followed up the study, ultimately discovered that this agouti protein … is involved in the rapid pigment changes that allow fish to adapt to their environment.”

This phenomenon, called background adaptation, also has been observed in mammals. The coat of the arctic hare, for example, turns from brown in summer to white camouflage against the winter snow.

In contrast to mammals that have to grow a new coat to adapt to a changing environment, fish, amphibians and reptiles can change their skin color in a matter of minutes. The first agouti gene, which produces the striped “agouti” pattern in many mammals, was discovered in 1993. The same year, Cone and his colleagues at Oregon Health Sciences University in Portland reported the discovery of the gene that encoded the melanocortin-1 receptor, a key player in the pigmentation story.

In the current paper, Cone’s group reports that the newly discovered protein, AgRP2, regulates expression of the prohormone genes pmch and pmchl, precursors to melanin-concentrating hormone, which has a pigment-lightening effect. “Together, the versatile agouti proteins and melanocortin receptors are responsible for regulation of body weight, the banded patterns of mammalian coats, and even red hair in most people,” Cone said. The current work shows that agouti proteins are also involved in the camouflage mechanisms used in thousands of fish species.

Read the article.

If only the gene could be activated in humans as well!!!

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Posted in Biology, Evolution, Medicine, Science, Wildlife | 1 Comment »

Medicine Nobel to Robert Edwards for IVF

October 4, 2010
SvD: Thirteen minutes before midnight on July 25, 1978 Louise Joy Brown delivered a baby girl by Caesarean section at Oldham General Hospital outside Manchester UK.
The girl weighed 2610 grams and the responsible physician Patrick Steptoe was soon able to reassure the hundreds of journalists gathered that “all studies have shown that the child is completely normal. ” The news of the birth was a medical sensation. Louise Brown was the first child in the world born with the aid of in vitro fertilisation (IVF).

BBC: Robert Edwards, the man who devised the fertility treatment IVF, has been awarded this year’s Nobel prize for medicine. His efforts in the 1950s, 60s and 70s led to the birth of the world’s first “test tube baby” in July 1978. Since then more than four million babies have been born following IVF.

The prize committee said his achievements had made it possible to treat infertility, a medical condition affecting 10% of all couples worldwide.

(That’s one prediction I got wrong)

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Posted in Medicine, Science | 1 Comment »

Next week is Nobel week: My layman forecasts

October 1, 2010

This week I won a $10 prize in a lottery and my belief in my crystal ball is high (but I ignore the fact that the lottery tickets cost me $30).

Nobel Prize® medal - registered trademark of the Nobel Foundation

Nobel prize medal

Next week is Nobel week and the winners for Medicine will be announced on Monday 4th, for Physics on Tuesday 5th and for Chemistry on Wednesday 6th. I pass over the Literature, Economics and Peace prizes in silence but address my crystal ball as to the areas of research that will be honoured.

Medicine: The 2 areas that spring to mind are stem cells and genetic cancer research. To choose one I go for stem cells with Dr. Yamanaka included in there somewhere.

Physics: The 2 areas I see as most likely are either quantum physics or the expanding universe. To choose one I plump for the universe and Prof. Perlmutter among the recipients.

Chemistry: I am fascinated by new materials and with graphene being the flavour of the decade I choose work related to graphene as being the winner. To name a name it would be just if the first person to discover graphene received recognition and so I hope that Hanns-Peter Boehm is on the list.

In spite of my lottery win, I put the probability of being right on one count at no more than 1%, on two counts at 0.1% and being right on all 3 at 0.01%.

Add your favourites if you have any.

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Posted in Chemistry, Medicine, Physics, Science | 2 Comments »

Update: Two more papers retracted by Mount Sinai

September 24, 2010
Mount Sinai School of Medicine logo.png

Image via Wikipedia

There is an epidemic of retractions.

Retraction Watch reports that Gene therapy researcher Savio Woo has retracted two more papers in addition to the 4 retracted earlier.

Mount Sinai School of Medicine researcher Savio Woo, whom Retraction Watch reported last week has already retracted four papers from major journals as two postdocs have been fired from his lab, has retracted two more from Molecular Therapy: The Journal of the American Society of Gene Therapy.

The two papers, both from 2007, were “Metabolic Basis of Sexual Dimorphism in PKU Mice After Genome-targeted PAH Gene Therapy” and “Correction in Female PKU Mice by Repeated Administration of mPAH cDNA Using phiBT1 Integration System.” As Nature noted in its coverage of the other retractions, the papers apparently followed from a now-retracted paper in the Proceedings of the National Academy of Sciences that, as we noted in a previous post, “claimed to have discovered a possible cure for phenylketonuria, or PKU, in mice.”

Li Chen and Zhiyu Li were the pot-docs implicated.

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Nobel prize winner retracts more papers

September 24, 2010

Following quickly on the heels of Hausergate and the Mount Sinai misconduct, we now have a Nobel laureate  – Linda Buck – retracting two papers because results from her lab at the Fred Hutchinson Cancer Research Center (FHCRC) were not reproducible (which is a euphemism for faked data). This was not the first time. She also retracted a Nature paper in 2008 for much the same reason. One particular (former) postdoctoral researcher Zhihua Zou is identified as the culprit.

Dr. Buck is a Howard Hughes Medical Institute investigator and also a Member of the Basic Sciences Division at Fred Hutchinson Cancer Research Center and an Affiliate Professor of Physiology and Biophysics at the University of Washington. She was at Harvard Medical School from 1994 – 2002.

Linda B. Buck

Linda B. Buck

The Scientist reports that:

Two prominent journals have retracted papers by Nobel laureate Linda Buck today because she was “unable to reproduce [the] key findings” of experiments done by her former postdoctoral researcher Zhihua Zou, according to a statement made by the Fred Hutchinson Cancer Research Center (FHCRC), where Buck worked at the time of the publications.

These retractions, a 2006 Science paper and a 2005 Proceedings of the National Academy of the Sciences (PNAS)paper, are tied to a 2001 Nature paperthat she retracted in 2008, due to the inability “to reproduce the reported findings” and “inconsistencies between some of the figures and data published in the paper and the original data,” according to the retraction. Zou was the first author on all three papers and responsible for conducting the experiments.

The FHCRC is currently conducting an investigation into the issue, said Kristen Woodward, senior media relations manager, but no findings of misconduct have been made. John Dahlberg of the Office of Research Integrity declined to comment on the matter.

Yesterday The Scientist reported another case of faked data from the University of Washington. Postdoc fudged epigenetic data.

A former postdoctoral fellow at Washington State University has reportedly falsified data presented in two figures of an epigenetics paper, according to the Office of Research Integrity (ORI) report released late last month. The data fabrication resulted in the retraction of a 2006Endocrinology paper, but a repeat of the original study, which uses newer and more quantitative technology and confirms the paper’s conclusions, will be published next week inPLoS ONE.

“This was an extremely difficult issue for myself and the laboratory to deal with,” said Michael Skinner, a professor of reproduction and environmental epigenetics at WSU who headed the research.

According to the ORI’s report, Hung-Shu Chang, a visiting postdoc from Taiwan who worked in Skinner’s lab from 2005 to 2006, falsified sequencing data used to identify DNA regions in rat sperm cells that had different methylation patterns following treatment with an endocrine disruptor known as vinclozolin.

( Is it just coincidence that the post-docs apparently faking data both at Mount Sinai and in these cases all seem to be of foreign origin? Is it a case of “cheap labour” being pressurised by the need for publications?)

Read more:More retractions from Nobelist – The Scientist – Magazine of the Life Scienceshttp://www.the-scientist.com/blog/display/57699/#comments#ixzz10Q4NXwiY

Postdoc fudged epigenetic data – The Scientist – Magazine of the LifeScienceshttp://www.the-scientist.com/blog/display/57696/#ixzz10QD852cp


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Posted in Behaviour, Medicine, Science, Scientific Fraud | 2 Comments »

Human malaria may have come from gorillas (not chimps)

September 23, 2010

It is heartening to see that science generally works and understanding increases as one discovery leads to another and tentative conclusions from one do not stand in the way of coming to new and different conclusions. Solid and painstaking work in the field and the lab (and not like the so-called science where the grabbing of headlines or the chasing of tenure or generation of funds dominates).

Not very long ago (3rd August 2009) the BBC reported that

Common chimpanzee in the Leipzig Zoo.

Image via Wikipedia

” By looking at blood samples, a US team discovered all world strains of the human malaria parasite falciparum stem from a malaria parasite in chimps. They tell Proceedings of the National Academy of Sciences how the species shift probably happened 10,000 years ago when humans turned to agriculture. Although chimps were known to harbour a parasite – Plasmodium reichenowi – that is closely related to the most common of the human malaria parasites, Plasmodium falciparum, many scientists had assumed that the two had co-existed separately. But blood tests on 94 wild and captive chimpanzees in Cameroon and the Ivory Coast suggest falciparum evolved from reichenowi. Francisco Ayala, of the University of California, Irvine, and colleagues found eight new strains of reichenowi that had striking similarities to falciparum and were genetic precursors to the human disease. The leap could have happened as early as two to three million years ago, but most likely to our Neolithic ancestors as recently as 10,000 years ago”.

But further work reported by the BBC yesterday now shows that the human malaria parasite is more likely to have originated with the gorilla parasite.

Gorilla (Nature)

Gorillas may be the source of human cerebral malaria

“Until now, it was thought that the human malaria parasite split off from a chimpanzee parasite when humans and chimpanzees last had a common ancestor. But researchers from the US, three African countries, and Europe have examined malaria parasites in great ape faeces. They found the DNA from western gorilla parasites was the most similar to human parasites.

Malaria is caused by a parasite called Plasmodium, and is carried by mosquitoes. The most common species found in Africa, Plasmodium falciparum, causes dangerous cerebral malaria. Over 800,000 people die from malaria each year in the continent. Until now, scientists had assumed that when the evolutionary tree of humans split off from that of chimpanzees – around five to seven million years ago – so had Plasmodium falciparum. This would have meant that humans and malaria co-evolved to live together. But new evidence suggests human malaria is much newer. Dr Beatrice Hahn of the University of Birmingham, Alabama, in the US, is part of a team that had been studying HIV and related infections in humans and great apes.

To study the DNA of infections in wild apes, you cannot use blood samples. So the team collected 2,700 samples of faecal material from two species of gorilla – western and eastern – and from common chimpanzees and bonobos, also known as pygmy chimpanzees”.

http://www.bbc.co.uk/news/science-environment-11393664


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After Harvard’s Hausergate, now misconduct at Mount Sinai

September 21, 2010
Mount Sinai School of Medicine logo.png

Image via Wikipedia

Earlier this week, the blog Retraction Watch called attention to four recent paper retractions by noted gene therapy researcher Savio Woo of Mount Sinai School of Medicine in New York City. Today, the school said in a statement that two of Woo’s postdoctoral fellows have been fired for research misconduct and that an internal investigation has cleared Woo of any wrongdoing.

Two of Woo’s post-doctoral fellows at Mount Sinai School of Medicine were dismissed for “research misconduct,” said Ian Michaels, a spokesman for the institution. According to Michaels:

When Dr. Savio L C Woo came to suspect that two post-doctoral fellows in his laboratory may have engaged in research misconduct he notified the Mount Sinai Research Integrity Office. Mount Sinai immediately initiated institutional reviews that resulted in both post-doctoral fellows being dismissed for research misconduct. At no time were there allegations that Dr. Woo had engaged in research misconduct. As part of its review, the investigation committee looked into this possibility and confirmed that no research misconduct could be attributed to Dr. Woo, who voluntarily retracted the papers regarding the research in question. Mount Sinai reported the results of its investigations to the appropriate government agencies and continues to cooperate with them as part of its commitment to adhere to the highest standards for research integrity.

File:HippocraticOath.jpg

Wikipedia: A twelfth-century Byzantine manuscript of the Hippocratic Oath.

According to ScienceInsider, the names of postdocs Li Chen and Zhiyu Li were recently removed from Mount Sinai’s directory. Chen and Li were listed as first authors on the retracted papers. Three  major journals — Proceedings of the National Academy of Sciences, Human Gene Therapy, and the Journal of the National Cancer Institute — recently retracted papers authored by Woo and others.

In a retraction notice issued this month, Woo wrote that:

It was discovered that some of the micrographs in two papers we published [figure 4 in J Natl Cancer Inst 2008;100:1389-1400 (1), and figure 3 in Hum Gene Ther 2009;20:751-758 (2)] are apparently duplicated. This has been reported to the institutional research integrity committee by the authors and while the outcome of an investigation is pending, the undersigned co-authors respectfully request a retraction of both papers and sincerely apologize to our colleagues.

The four papers in question focus on two different areas of gene therapy research. One pair, published in 2008 in the Journal of the National Cancer Institute and in 2009 in Human Gene Therapy, investigate genetically engineered bacteria as a weapon against cancer. The other two papers describe a method for using bacterial enzymes to introduce therapeutic genes. A 2005 paper in the Proceedings of the National Academy of Sciences reports experiments in which mice with the metabolic disorder phenylketonuria appeared to be cured using this method. As a demonstration of the promise of gene therapy, that work garnered some media coverage, includingthis article in Science. A 2008 paper in Human Gene Therapy described the use of the technique in human cells.

Source: http://blog.the-scientist.com/2010/09/20/new-in-a-nutshell/

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Posted in Behaviour, Ethics, Medicine, Science, Scientific Fraud | 2 Comments »

Indian superbug now in 14 countries

September 14, 2010

The widespread and indiscriminate use of antibiotics in India has probably helped in making the superbug NDM1 (New Delhi metallo-beta-lactamase-1) resistant to virtually every known antibiotic. The defensive attitude taken by the medical profession in India when the Lancet report was first published is less apparent now and the Government has been forced to address the issue of the use of antibiotics.

image:jetlib.com

Three cases have been found in the US. Three people returned to the US from India earlier this year infected with the newly described “superbugs” that are highly resistant to antibiotics, according to media reports. All three confirmed cases – one each in California, Illinois and Massachusetts – involved people who got medical care in India. The Illinois patient recovered, and there is no evidence the infection was transmitted to other people. Another person was treated at Massachusetts General Hospital and isolated, a measure that prevented the germ from spreading, said David Hooper, chief of the hospital’s infection control unit, the Boston Herald said. The Massachusetts patient too survived. The daily said the superbug seems to have been contained. All three patients developed urinary tract infections that carried a genetic feature that made their cases harder to treat.

Taiwan on Thursday decided to declare it a category-four communicable disease. According to Taiwan’s Centre for Disease Control, NDM-1 has the potential to become a serious public health problem as the superbug is extremely virulent and resistant to almost all antibiotics, even the most powerful ones.

Sify comments that:

The Government of India has constituted a committee to formulate a policy for the rational use of antibiotics. The 13-member task force, chaired by the Director-General of Health Services, is expected to submit a report within two months.

The task ahead is Herculean, because it requires a change of culture both on the part of doctors and patients. In a country where a significant portion of the people cannot afford most useful medicines, doctors routinely over-prescribe antibiotics to those who consult them. What is worse, patients are often dissatisfied with a doctor who may advise that, say, a viral infection should be roughed out if it does not get serious and not be pointlessly treated with antibiotics. This is, of course, just a little better than in China where many patients are not satisfied unless a doctor prescribes an injectable. Poor and uninformed patients in India also routinely use an older prescription to treat a new ailment whose symptoms appear similar, and then do not complete a course once undertaken. Further, although antibiotics are to be sold only against prescriptions, chemists routinely sell them over the counter, acting as makeshift doctors in response to patients’ narration of symptoms and request for some tablets.

It is also necessary to examine what can be done to counter the depredations (there is no other word for it) of drug companies and their armies of medical representatives at whose request most doctors do their prescribing. The best long-term weapon is right public awareness on these issues. Civil society has a larger role to play in this regard than government.

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Indian “superbug” report is a scare to hurt medical tourism?

August 12, 2010

The Times of India is not impressed by the report in The Lancet Infectious Diseases Journal which claims that “India also provides cosmetic surgery for Europeans and Americans, and it is likely the bacteria will spread worldwide.”

cartoon from indianmta.blogspot.com

Scientists have tracked down a drug-resistant superbug that infects patients and causes multiple organ failure to Indian hospitals but doctors here see in it the germ of a move to damage the country’s booming medical tourism industry. While the study has the medical world turning its focus on infection control policies in Indian hospitals, the Indian Council of Medical Research has alleged a bias in the report and said it is an attempt to hurt medical tourism in the country that is taking away huge custom from hospitals in the West. “Such infections can flow in from any part of the world. It’s unfair to say it originated from India,” said ICMR director Dr VM Katoch. The superbug NDM-1 (New Delhi metallo-beta-lactamase) is named after the national capital, where a Swedish patient was reportedly infected after undergoing a surgery in 2008.

Senior doctors working in infection control said India lacks policies on antibiotics, infection control and registries for hospital-acquired infections. By the ICMR director’s own admission, India cannot scientifically fight back allegations of being the source of such superbugs, as the country does not have a registry of such hospital-acquired infections.

“Two in every five patients admitted to hospitals acquire infections. This extends the patient’s stay in the hospital, increases the expenses and causes side-effects,” said Dr Dilip Mathai, head of the department of internal medicine, Christian Medical College, Vellore.

The Lancet report  is causing some alarm within the medical tourism fraternity in India and doctors are rushing to defend the business.

But doctors in India said there was little chance this bacteria would infect overseas “health tourism” visitors. “Most of these bacteria are mostly transmitted to ICU patients, those in ventilators or critically ill patients. Since overseas patients come for selective surgeries, chances of them getting these bugs are negligible,” said Dr Monica Mahajan, senior consultant at Delhi-based Max Healthcare. Dr Amit Verma, director of critical care medicine at Fortis said he did not anticipate any major impact to medical tourism in India. The sample size of the study was very small to arrive at a conclusion, he said, adding that the chances of the bacteria becoming a global epidemic was negligible due to the restricted transmission capability of the bacteria.

Somehow the glib statement that “Most of these bacteria are mostly transmitted to ICU patients, those in ventilators or critically ill patients. Since overseas patients come for selective surgeries, chances of them getting these bugs are negligible” does not inspire much confidence!

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Posted in Alarmism, Ethics, Medicine | 1 Comment »

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