Health and Medicine – Page 35

Nanotechnology and medicine

X-ray imaging is a very mature, although not infallible, field of medicine, but it does not lend itself to the detection of small tumours or their metastases. Now, Sangeeta Bhatia in Boston, Massachusetts and colleagues at the Harvard-MIT Division of Health Sciences and Technology hope to remedy that by using iron oxide nanoparticles to allow MRI to visualize areas of tumor invasion.

The key to their novel imaging agent is a tumour-specific protease, which is found, as the name would suggest, primarily in and around tumour cells. Bhatia and her team engineered a method by which iron(III) oxide nanoparticles could form aggregate clusters under physiological conditions.

Find out more about how Bhatia and her colleagues hope to exploit nanotechnology to improve medicine in my current news round-up on SpectroscopyNOW.com

Human to human bird flu

The World Health Organization has expressed concern that a recent cluster of deaths associated with the H5N1 virus in Indonesia may not have originated with an animal host, suggesting the possibility of human to human transmission of the virus. However, it also cautions that the analytical evidence suggests that the virus has not mutated into a human transmissable form, which means we are not just yet on the verge of a global bird flu pandemic after all.

The news media inevitably picked up on this warning and ran with it, but thankfully the BBC saw the double-edged nature of the WHO announcement points out with some degree of rational response that many people in Indonesia, as in other southeast Asian countries, live in such close proximity to their animals and not necessarily in the most hygienic of circumstances that the likelihood of catching bird flu is much higher in such an environment.

It is the lack of a mutated form of H5N1 among these victims that means we are not yet doomed to see the feathers fly globally.

Doctors take an alternative view

A group of leading physicians and scientists in the UK has petitioned the National Health Service, because it is concerned about how unproven or disproved treatments are being encouraged within the system. In a letter reproduced in The Times, they ask that practices be reviewed and that the various concerns about such treatments, which generally sit under the umbrella of complementary or alternative medicine, be raised with the governmental Department of Health.

The bottom line, in other words, is that the authors of the letter, “want patients to benefit from the best treatments available” and don’t think NHS money should wasted on including the likes of highly implausible treatments such as homeopathy on the treatment roster.

The authors express the opinion that, “We are sensitive to the needs of patients for complementary care to enhance well-being and for spiritual support to deal with the fear of death at a time of critical illness, all of which can be supported through services already available within the NHS without resorting to false claims.”

Homeopathy is certainly one of the most inflammatory of the CAM therapies. From the scientific standpoint there is absolutely no serious explanation as to how it might work in terms of the chemical components of the treatments. On the other hand, Toby Murcott’s excellent book on the subject of alternative medicine (reviewed briefly here) emphasises that science is yet to explain fully the placebo effect, or more intriguingly the anticipatory effect of treatments wherein the thought of being healed can have some benefit for many patients even before they are given the therapy.

Modern medicine has “eradicated” so many of the old diseases, that countless health centres and organisations across the globe now must heavily promote their various panaceas as the diseases of longevity begin to stack up for which there are no cures as quick and easy as a course of tablets.

As we live longer, so we expect to live healthily for longer. With that in mind it is inevitable that people will turn to CAM to help give achieve this. However, in this letter, Professor Michael Baum and colleagues essentially point out that the hopes of many patients are being pandered to through the irresponsible embracing of alternative therapies for which there is no evidence of efficacy.

Youths and Adults First for Flu?

In today’s Science magazine policy forum, Ezekiel Emanuel and Alan Wertheimer of The Clinical Center, at NIH in Bethesda, Maryland, argue that should a [bird] flu pandemic emerge, any time soon, then, they say, priority should go to people between early adolescence and middle age.

Their argument is based on the idea that every one of us should have the opportunity to live through all life stages. They suggest that this offers the best balance of the amount the person has invested in his or her life with their time left to live should this virtual disease prove closely to 100% fatal without vaccination.

Their suggestion contrasts starkly with current recommendations for vaccinating people in the event of a flu pandemic which involves prioritizing vaccination of health workers and the elderly ill at the very top and healthy people aged two through 64 at the very bottom. The pair recommend incorporating another ethical principle that focuses on ensuring safety and the provision of food and fuel. What’s most intriguing about their argument, however, is that their ethical framework is intended to be applied only to the USA and not the whole world. The Science press release pertaining to this suggestion, simply says that this “would then involve more complex issues of global rationing.”

So, what do sciencebase readers think? Who’d care to draw up the list?

Pastel Chef and Chemist

In this week’s Alchemist I vaingloriously pronounced that oncologists might soon be able to image tumours as quickly and easily as radiologists view broken bones with X-rays.

Sciencebase contributor Dan Lednicer, a retired organic chemist turned pastel chef emailed me to point out that the statement regarding the power of X-rays required qualification:

“One day this last February, I happened to fall on my side in a parking lot. The persistent pain led me to get an X-ray the next day. This showed nothing out of the ordinary. When getting dressed one morning a week later, I found that any weight on my left leg led to excruciating pain. An X-ray in the emergency room at the hospital still showed nothing. It took an MRI (I almost wrote NMR!) to show a clean brake high up on the femur.

I now sport an impressive metal rod with a couple of appurtenances down the middle of that femur. This sails through metal detectors like a breeze, as it is made of titanium.”

So, it seems. X-rays are not the gods of imaging that my flippant remark would suggest. As to why titanium does not show up on airport metal detectors would make an interesting assignment for science class. Feel free to post your thoughts…

Disease Mongering

I was a bit tardy covering the recent conference on disease mongering, but to make up for it have posted a new poll on the SciScoop site to give visitors a chance to voice their opinion.

A conference held April 11-13, in Newcastle, Australia, raised some serious questions about the motives of the pharmaceutical industry. The patents on drugs for old-fashioned diseases that were originally making a $1billion a year are almost all expired and new avenues of research under the umbrella of biotech have yet to make the same level of return for other diseases. As such, there is a feeling among some observers that “new” conditions, such as restless legs syndrome, attention deficit hyperactivity disorder (ADHD), and sexual dysfunction are being hyped by the industry as the serious ills of our time that need new (lucrative) treatments. Is this the case or can we simply not do without the chemical fix of those repeat prescriptions? A collection of freely accessible essays on the subject of disease mongering is available on the PLOS Medicine site.

Visit SciScoop to vote in the poll and help us answer the question – “Are we drug company puppets?”

Preventing the Spread of Bird Flu

cockerel In the week that the H7 variant of avian influenza has led to the culling of 35000 chickens in England, scientists at Imperial College London have simulated the spread of a “human” bird flu epidemic and say that rapid treatment and isolation of infected individuals not only from the public but their household contacts will be essential to prevent thousands of deaths. They also suggest that vaccine stockpiles should be gathered together in readiness for a pandemic, even if the vaccine is not very potent. However, it is strict border controls and travel restrictions that will be needed to slow an outbreak and prevent a global pandemic.

Neil Ferguson and colleagues used computer modelling to evaluate the influence of a range of anti-pandemic measures, such as treatment and prophylaxis with antiviral drugs, household quarantine, vaccination and restrictions on travel. They found that with a policy of giving antiviral drugs both as treatment to infected cases and prophylactically to the patient’s families coupled with early closure of schools hit by the outbreak, rates of disease could be cut by almost a half.

However, for this policy to be feasible, antiviral stockpiles would need to be sufficient to treat 50% of the population – twice what many countries are planning. Combining such a policy with targeted immunization of children with a stockpiled trial vaccine might reduce illness rates by two-thirds, even if the vaccine was not particularly effective in its protection. Even greater drug coverage would have a correspondingly larger protective impact. Ferguson provides more details in this week’s Nature.

Bird Flu in Britain

The BBC reports this morning that about 35,000 chickens at a poultry farm in Norfolk, England, are to be culled after dead birds tested positive for a strain of bird flu. What makes this interesting is that the newsdesk subbies are now going to have cope with another strain of avian influenza – H7, as opposed to H5N1. H7N7 was, of course, responsible for an outbreak in The Netherlands where 30 million birds had to be slaughtered, but this is the first time it has reached British shores. H7 is not as great a risk to human health as H5N1, although H7N7 infected 80 people in The Netherlands. Bacteriologist Hugh Pennington of Aberdeen University, said that while the H7 strain was “nasty for the birds”, it was “not a public health threat to humans”, the BBC reports. “It’s basically a virus that kills chickens and has been around for many, many years.

So, one might ask, why did the BBC get a quote from a professor of bacteriology, rather than virology?

Defining Obesity

Following on from Wednesday’s posting on the subject of an obesity stifling pill, health professionals have been told that they need to use more than tape measures and scales to define and tackle obesity. The claim appears in the British Journal of Advanced Nursing.

Maryanne Davidson of Yale University discovered that many women fail to make the link between high weight and poor health and that culture is to blame, playing a key role in how positively they see themselves. Davidson reviewed key papers published over a 10-year period to see how health professionals and black and white American women define obesity and to identify differences in attitudes.

The study revealed that while health professionals used quantitative methods, such as Body Mass Index (BMI) measurements based on the height to weight ratio, women are more likely to base their ideal weight on cultural criteria. “My review revealed that black American participants defined obesity in positive terms, relating it to attractiveness, sexual desirability, body image, strength or goodness, self esteem and social acceptability,” Davidson says, “In addition they didn’t view obesity as cause for concern when it came to their health.”

White Americans, on the other hand, expressed completely the opposite view: “They defined obesity in negative terms, describing it as unattractive, not socially desirable, associated with negative body image and decreased self-esteem and being socially unacceptable,” explains Davidson. Worryingly, she adds, “when it came to the links between body weight and health, this group was much more likely to voice mixed views, with some expressing concern and others feeling that weight wasn’t a health issue.”

From the clinical care perspective, Davidson has also discovered that there are variations in how health professionals define obesity. “Although most of them use BMI to actually measure obesity, we found different views about what level of BMI constitutes normal weight and what level indicates obesity,” she says. Such findings provide a real challenge for healthcare professions.

People have been obsessed with their weight since records began, Davidson adds. She points out that the “Spartans” reportedly ostracised a man for being too fat and Socrates danced every day to keep his weight within reason! Such apocryphal tales tell us nothing about the health implications of being overweight today.

People see this as a genuine issue and spend a lot of money on trying to reduce their weight. Others spend time in the gym and take the healthy option while others face the risks of going under the knife. Bariatric surgery and liposuction prices are just a few of the factors that potential patients must consider.

“Obesity is a major issue for health professionals as it is emerging as a worldwide healthcare epidemic,” says Davidson, “The World Health Organization estimates that there are at least 300 million obese people worldwide and a further one billion who are overweight.”

Hormone Stifles Appetite, Fights Obesity

Researchers in the UK have discovered that topping up levels of a gut hormone could help people stave off feelings of hunger as well as increase activity in overweight and obese people.

According to research to be published in the International Journal of Obesity injections of the appetite-suppressing hormone oxyntomodulin, which is found in the lower intestine, have a “double effect” on people.

Chief researcher Steve Bloom of Imperial College London points out that, “The discovery that this hormone has a double effect, increasing energy expenditure as well as reducing food intake, could be of huge importance. When most people diet, this produces a reduction in activity, which is probably an adaptive trait to conserve energy during times of famine. However, this does make it especially difficult for obese individuals trying to loose weight. In contrast, oxyntomodulin decreases calorific intake, but actually increases energy expenditure, making it an ideal intervention for the obese.”

The research builds on Bloom’s earlier findings reported in the journal Diabetes in 2005, which were hailed as a major breakthrough in treating obesity.