David Bradley – Page 309

A sweet little fairy story

The fairies at the bottom of my garden have been digging up the pot of gold at the end of the rainbow. A spokesdog for the Society of Wolves tells me that Canis Lupus is no longer dining on geriatric homeowners nor juvenile females in crimson headgear. Oh, and there is no link between sugar in the diet and diabetes.

The first two statements may seem a little far-fetched but that last one, surely it’s a fairy story…

Well, apparently not. In a press release posted on AlphaGalileo by the UK’s Sugar Bureau, new evidence from researchers at the Royal Victoria Hospital and Queen’s University Belfast suggests that receiving a quarter of daily calories from sucrose (sugar) as part of a balanced, weight-maintaining diet does not result in any difference in insulin resistance compared to getting 10% of the same number of calories from sucrose.

The press release states, that “It has long been suspected that a high sugar diet over a long term period may lead to an increased risk of developing diabetes. But there has been little or no evidence to support this idea, with studies on the role of any aspect of the diet in the development of diabetes difficult to conduct.”

So, is this the evidence we’ve all been waiting for?

The research, published by Steven Hunter and colleagues in the journal Diabetes points to sugar’s innocence. “Sugar has traditionally been linked to the development of diabetes,” he says, “These findings challenge that thinking, and show that intakes of more than double that currently recommended do not appear to have an adverse effect on markers of diabetes risk.”

But, let’s take a closer look at this little story from the Sugar Bureau. The trial studied the effects of different amounts of sucrose in the diets of 13 healthy men without diabetes over a period of six weeks.

Thirteen volunteers? Six weeks?

How can they draw any serious conclusions from such a tiny sample tested over such an incredibly short period? Where is the data on sucrose intake for hundreds if not thousands of people over several years of sucrose abuse? While there is evidence that saturated fat intake and obesity are closely linked to diabetes risk, this single very small study cannot seriously claim that sugar intake has no effect on diabetes risk. How can they tell in a month and a half with just 6 or 7 men being fed a larger amount of sugar in their diet?

I don’t doubt the researchers’ integrity, but this news, coming as it does from the Sugar Bureau, does smack of sickly sweet spin to my cynical eye. It doesn’t tell us anything about the long-term effect of repeated blood sugar spikes caused by excessive intake nor about the effects of aging on sucrose processing and the harmful cross-links it can form with body proteins.

It’s a story that will have the tooth fairy rubbing its hands in glee as well as giving anyone with a penchant for two desserts the impression that they can get away with a large amount of sugar in their diet without having to worry about diabetes. I find it hard to imagine a happy ever after for this story.

What do you think? Should organisations or companies that promote a particular product be allowed to fund scientific research into the benefits or otherwise of that product?

Too much protein increases cancer risk

Earlier this week scientists reported a strong correlation between obesity and the risk of common cancers, such as cancer of the colon and breast cancer. Today, initial findings from a US study suggest that eating less protein could be a way to protect some people from cancers that are not directly associated with obesity.

The research is published in the December issue of the American Journal of Clinical Nutrition (2006, 84, 1456), shows that lean people on a long-term, low-protein, low-calorie diet or participating in regular endurance exercise training have lower levels of plasma growth factors and certain hormones linked to cancer risk. “However, people on a low-protein, low-calorie diet had considerably lower levels of a particular plasma growth factor called IGF-1 than equally lean endurance runners,” says Luigi Fontana of Washington University, “That suggests to us that a diet lower in protein may have a greater protective effect against cancer than endurance exercise, independently of body fat mass.”

“Our findings show that in normal weight people IGF-1 levels are related to protein intake, independent of body weight and fat mass,” Fontana says. “I believe our findings suggest that protein intake may be very important in regulating cancer risk.”

Fontana says most of us don’t eat nearly enough fruits and vegetables or enough whole-grains, cereals or beans. “Many people are eating too many animal products – such as meat, cheese, eggs and butter – as well as refined grains and free sugars,” he says. “Our intake of vegetables and fruits is low, and beans are vastly underconsumed in the U.S. and Europe these days.”

He believes diets would be healthier if we ate more whole grains, beans, fruits and vegetables and far fewer animal products. He recommends mostly fish, low-fat dairy products and, occasionally, some red meat. Such a diet would both cut total calories and reduce the amount of protein we consume to healthier levels.

“Eating too many calories increases our risk of developing obesity, diabetes, cardiovascular disease and of certain types of cancer related to obesity,” Fontana adds, “We hope to further clarify what happens to cancer risk when we are chronically eating more protein than we need.”

AIDS in Libya

Previously we reported on the case of six medical workers in Libya who face the death sentence having been charged with deliberately contaminating more than 400 children with HIV in 1998. The evidence in their defence has now reached the molecular level and is published today online in Nature.

Oliver Pybus and colleagues in an international research team has used the genetic sequences of the viruses isolated from the patients to reconstruct the exact history, or “family tree” of the outbreak. They assessed accumulated mutations and have demonstrated unequivocally that the HIV subtype involved in this case was already infecting patients well before the medical workers had even set foot in Libya.

The trial ended on November 4 and the verdict is expected for December 19. However, a growing body of scientific evidence already suggested that the outbreak was caused by poor hospital hygiene rather than deliberate action.

Thomas Leitner of Los Alamos National Laboratory has provided forensic HIV evidence in more than thirty such cases over the past fifteen years. He describes the Nature paper as “compelling evidence that the outbreak had started before the accused could have started it.”

Do you agree? What else should we as outsiders be doing if anything?

Changing face of XP

Running Windows XP, fancy a change of scene, then download the newly released Zune theme from Microsoft. To my eye, it’s a less juvenile colour scheme than the standard XP theme with its primary colours etc.

Zune theme

There’s a totally pointless video on the web showing you how to install it, but all you have to do is click that link, save and run the MSI file and then hit “Apply” as and when.

Of course, if you’re on Linux or Mac you probably couldn’t care less about the latest XP theme, but if you’re on XP and have people walking by your desk on a regular basis you could probably persuade some of them at least that you’ve got Vista already, without having to actually install it. Or maybe not.

Is the “old” XP them too garish? Have you installed the Zune theme? What do you think of it? Are the desktop and taskbar items as clear as they are in the original?

Catalyzing the hydrogen economy

In order to make biofuel production from biomass as efficient as possible it will be crucial to understand the underlying chemical mechanisms running the reactions. Researchers in Northern Ireland are using infra-red spectroscopy and mass spectrometry to get to the core of the problem.

Frederic Meunier of the CENTACAT research labs at Queen’s University Belfast and his colleagues like many other scientists expect hydrogen to be the currency of the hydrogen economy and that the mint will rely on effective and inexpensive catalysts to produce the gas from renewable resources, such as biomass. Meunier and his colleagues are investigating platinum and rhodium based catalysts used to line the hollows in porous alumina or cerium zirconate.

Get up to speed on the details in SpectroscopyNOW

Is the hydrogen economy going to solve our energy woes? What do you think?

Cholesterol drug withdrawal

According to the FierceBiotech pharma newsletter, Pfizer has been forced to halt development of its cholesterol drug Torcetrapib. The report says that the Data Safety Monitoring Board recommended the withdrawal of the drug from trials because of an “imbalance of mortality and cardiovascular events”.

I presume that’s management speak for “too many patients were having heart attacks and dying”.

The drug was set to become a Pfizer blockbuster, although I’d have hoped the marketing people would have come up with a snappier name before it went to market. “Based on all the evidence we have seen regarding Torcetrapib and in light of prior study results, we were very surprised by the information received from the DSMB,” the company stated. The DSMB has privileged access to the blind trials information so that it can make such decisions in the public and patient interest, but Pfizer claims the announcement was “totally unexpected and disappointing”.

The drug was set to replace Lipitor, a $12b a year blockbuster the patent on which is soon to expire. The FB newsletter says, that Pfizer “continue to invest in a wide range of pipeline opportunities across a diverse range of therapeutic areas.” Which, I presume, is management speak for “back to the drawing board”.

Apparently, just two days before this withdrawal, the company was enthusing about its benefits? Should we be policing drug trials even more stringently than we are now to prevent products getting so far before it is discovered there are serious issues with a particular trial?

Highly strung

Stradivarius violin Infrared and NMR spectroscopy have possibly revealed one of the great secrets of the violin makers Stradivari and Guarneri del Gesu – they used chemical wood preservatives to help preserve their instruments and to improve the tonal quality. The discovery could help modern-day violin makers emulate more closely the properties of irreplaceable violins from the 18th Century and well as providing music conservationists with new insights on how to best preserve the antique instruments.

Joseph Nagyvary at Texas A&M University, in College Station, and colleagues, reveal in a brief communication to the journal Nature how the maple wood used by the celebrated craftsmen could have been chemically processed before the violin makers even began crafting the wood. The researchers have analysed in detail the organic matter from small samples of shavings retrieved from the interiors of five antique instruments during repairs.

Get the score here

How Not to do Cosmetic Surgery with WD-40

Ever had the urge to hit an aerosol hard with a sledgehammer, and then thought better of it?

This video will serve as a nice little warning to any budding vandals out there who think it would be fun to smash a burning can of WD-40.

WD-40, as most Sciencebase readers, will know is a petroleum product used to quickly lubricate sticky metal joints, nuts, bolts, bike chains and such. It was named by the product’s developers Rocket Chemical Company and refers to the fact that the successful water displacement formulation was made on the fortieth attempt. Obvious really, and certainly not an urban legend. Whether or not this video clip will become an urban legend one has to wonder, it doesn’t look like the guy is wearing any protective clothing other than his nice blue baseball cap. Puts a whole new slant on the term chemical peel!

Of course, the video is surely a publicity stunt of some kind, either that or the guy’s amazingly fast drop and roll to extinguish the flames was well rehearsed before hand. How else can you explain his keeping his composure to do that while his face is on fire? I certainly wouldn’t advise anyone to give this a go. By the way, there’s actually no visible evidence that this was WD-40 at all (other petroleum-based lubes are available).

Expanding proteins

Expanding proteins A new study reveals that the static snapshots recorded in protein crystallography may be missing the bigger picture. Investigations of a bacterial protein using cryomicroscopy shows the protein in a balloon-like mode previously hidden from sold state studies. The discovery suggests that techniques complementary to X-ray crystallography are essential if molecular biology is to gain a complete understanding of protein structure.

Steven Ludtke, assistant professor of biochemistry and molecular biology and co-director of the National Center for Macromolecular Imaging at Baylor College of Medicine and colleagues Dong-Hua Chen and Wah Chiu there and Jiu-Li Song and David Chuang at The University of Texas Southwestern Medical Center in Dallas, studied a mutant protein and came to this perhaps not so startling conclusion. The protein GroEL chaperones misfolded proteins and nudges them into their active folded state in the cell. Protein misfolding is implicated in a number of neurodegenerative diseases, such as Alzheimer’s disease and the prion diseases including Creutzfeldt-Jakob disease.

The full story is now available at SpectroscopyNOW

Raman best for breast cancer

Breast cancer remains the most common form of cancer among women but screening with mammography involves exposure to ionising radiation and suffers from a high rate of false positives that then require a definitive assay. In the December issue of the journal Biopolymers, researchers in India describe how Raman spectroscopy might be used to discriminate between normal, benign, and malignant breast tissue and so provide a simple and relatively non-invasive complement to a suspicious mammogram.

Murali Krishna of the Center for Laser Spectroscopy at Manipal Academy of Higher Education, in Karnataka and a visiting scientist at the University of Reims, France, and colleagues at Department of Surgical Oncology, Shirdi Sai Baba Cancer Hospital and Research Center and the Department of General Surgery at Kasturba Medical College, both part of Manipal, explain that, as with most cancers, survival rates depend on the stage at which diagnosis is made. More reliable screening and diagnosis methodology could thus improve survival rates.

Read on…