Health and Medicine – Page 42

Flight of the humble bee

By combining videos of free-flying honeybees with information from robotic models, researchers have come up with a sweet solution to explain the aerodynamics of bee flight.

Most flying insects beat their wings in large strokes to help them fly. But certain types of bee have to be different.

Michael Dickinson and colleagues demonstrated that honeybees fly using much shorter strokes (approximately degrees) and beat them faster than is to be expected based on the size of the bee. Aside from exploiting the effects of the wings rapidly changing at the start of each stroke, it also means that the bees’ buzz is of a much higher frequency than it should be.

By using a high-frequency, low-amplitude stroke, honeybees can gain a much wider range of aerodynamic power than other insects, which comes in handy when they’re loaded up with pollen.

Not exactly a story for the onset of winter here, but it got me buzzing (Hah!)

Treating Drug Addiction

There is not much in the plant world that people have not sniffed, snorted, smoked, rubbed in, injected or attempted to get inside their bodies in other ways in the hope of eliciting someone kind of magical response. The well-known plants that gave a positive result in the primitive tests – the coca plant, poppies, marijuana, tobacco, betel trees, coffee beans – have since grown infamous leaving the air heavy with their tragic scent in so many places. Find out about the plant that itself could be used in the fight against drug addiction.

Bird Flu Test

Researchers at McMaster University, Toronto, have developed a simple diagnostic that can spot all the major human respiratory viruses, including SARS.

The press release announcing this finding includes in the list of “major” viruses – H5N1 (bird flu), but H5N1 is yet to become a “major” human virus having only killed a few dozen people in the forty-odd years since it emerged! This contrasts sharply with the more common influenza type A viruses to which humans have been exposed for centuries that have killed thousands upon thousands.

Obviously, the writer of the press release wants to get the item into the media, hence the mention of H5N1 and SARS, and, admittedly, the diagnostic, which is still undergoing clinical evaluation, will be able to spot those viruses. There is enough disinformation regarding avian influenza as it is. It seems that almost any piece of viral research is likely to have some PR exploitable link to H5N1 these days, but there are two sides to every story and a lot of researchers have stated already that should H5n1 ever mutate into a human transmissable form it will lose its lethality without doubt. After all, it doesn’t kill wild birds, just that pampered stock we breed to eat.

Newborn Bonding

Compared with children raised by biological parents, children who were raised in foreign orphanages before adoption by American families apparently have altered levels of social-bonding hormones, researchers report.

Researchers are interested in how infants’ social experiences can affect brain organization. Seth Pollak and colleagues studied children adopted into American families after being raised from birth in foreign orphanages, where they often failed to receive standard emotional and physical contact from caregivers.

The researchers compared these children with a control group of American children raised by their families. Two hormones were of interest to the researchers: oxytocin and arginine vasopressin, both of which are associated with stress regulation and social bonding, and whose levels rise after socially pleasant experiences such as comforting touches.

Compared with the control group, children raised in orphanages showed lower baseline levels of vasopressin. Also, oxytocin levels of family-raised children increased after playful social contact with their mothers, but orphanage-raised children did not display the same response. The results suggest that a failure to receive typical care as a child can disrupt normal development of these hormonal systems, which can then interfere with the calming and comforting effects that typically emerge between children and their caregivers.

Amazing what a little interpersonal chemistry can do, isn’t it?

SOURCE: PNAS Press Release

Homeopathic Flu Remedy

It’s rather worrying to see the proliferation of books about avian influenza, as if people aren’t scared enough, but this one is more worrying still – its title alludes to the idea that homeopathy can somehow help us survive influenza epidemics and pandemics. Bizarrely, it says we can survive “past, present and future” episodes. Present and future are really pushing it, given the lack of valid trials of homeopathy in any area of medicine, but “past”?

Forget H5N1, H3N0 is a killer too

According to the People’s Daily Online, the first Vietnamese have died of H3N0 another strain of the influenza A virus, related to but different from the increasingly familiar H5N1. From the scaremongering point of view, there’s no need to hold the frontpage (at least outside Vietnam) as this strain is far less virulent than H5N1.

However, it does bring to light an aspect of flu viruses that gets little mention in the media – avian influenza has killed very few people, especially compared with the number of annual deaths from human influenza, but should any of these avian strains jump between species they are likely to lose their virulence to a great degree. One flu expert told us that, “H5N1 will surely decrease in lethality as it becomes more infectious between humans…no doubt about it.” More on that next week…

Molecular Model of Oseltamivir (Tamiflu)

tamiflu molecular structure Premier molecular modeller Stephan Logan has produced for us a timely reminder of the chemical structure of Tamiflu, the antiviral flu drug. You can order the necessary components to build the Molecular Model of Oseltamivir (Tamiflu) and other molecules from Stephan’s site. Perfect for that avian flu lecture!

In case you missed my how to avoid colds and flu article, it’s once again taking pride of place on the sciencebase site.

Symptoms of Bird Flu

There’s a lot of hyperbole in the media regarding the allegedly imminent bird flu epidemic – I’ve put together what I hope is a balanced bird flu FAQ here – Symptoms of Bird Flu. Please let me know what you think, whether this article makes you more concerned about bird flu or whether it has allayed some fears.

Bacterial Viruses

In his otherwise intriguing book, Digital Fortress ($7.99 in paperback from Amazon US), author Dan Brown makes several schoolboy errors. For instance, top of page 69 he says that, “Computer viruses were as varied as bacterial viruses…”

I doubt he is referring to bacteriophages here and is simply making the mistake that bacteria and viruses are essentially one and the same, i.e. germs! That aside, computer viruses are by no real measure as varied as biological viruses. There are, of course literally tens of thousands of computer viruses and worms, but essentially they are all variants of a few hundred that exist “in the wild”. In contrast, there is at least one virus for every species on earth…and that’s almost beyond counting.

Arsenic Problem

On the day I publish an item on a new arsenic assay , I received an email from an old contact of mine Dipankar Chakraborti of Jadavpur University who is at the forefront of As science and finding a solution to this insidious problem facing the Indian subcontinent and beyond.

Here’s what he had to say:

“To understand the exact magnitude of groundwater arsenic contamination and its health effect in West Bengal, India we have studied one of the arsenic affected district Murshidabad out of nine affected districts in West Bengal in details for last seven years with twenty people in our group including a dermatologist, neurologist, gynaecologist, pathologist, analytical chemist, biochemist, geologist, civil engineer, etc.

We have analyzed about 30,000 water samples from this district alone and screened 25,274 people with our medical group for arsenical skin lesions and other related arsenic toxicity. We have also analyzed 3843 biological samples (hair, nail urine and skin scales).

We have studied in details the district Murshidabad as a whole and semi micro and micro level studies in one block, one Gram Panchayet (cluster of villages), one village and published five papers in peer-reviewed international journals.”

Email me if you’d like to receive a PDF file carrying the complete citations from Dipankar.

For more information on the arsenic problem, read my Guardian article on the subject.