The Great Impostors

The Great Impostors
Well said, hard hitting, if health services can be commercialized why not ecosystems?

Drink coffee moderately and regularly; it may reduce heart failure risk

I did not know that coffee drinking can have some benefits. I drink two cups a day one in the morning and one in the evening. I was pleased to read that  researchers from the Cardiovascular Epidemiology Research Unit at Beth Israel Deaconess Medical Center in Boston, Harvard School of Public Health, Boston, Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Boston,  Department of Epidemiology, University of Alabama at Birmingham, Birmingham, showed that  by drinking coffee regularly and in moderation, you could reduce your risk of heart failure; the new study was published in the American Heart Association's journal Circulation: Heart Failure.

They did not do any study themselves; but searched electronic databases (MEDLINE, EMBASE, and Cinahl) from January 1966 through December 2011 with the use of a standardized protocol to analyze previous studies on the link between coffee consumption and heart failure.

Why did they do this research? They learnt that the studies so far to find linkage between coffee consumption and heart failure gave conflicting results.

They used "coffee" and "heart failure" as the key words and reviewed the reference lists of retrieved articles. They analyzed all articles with an abstract suggesting that it was relevant.

The search identified 116 publications. They excluded 27 duplicates. An additional 84 articles were excluded after review of the title or abstract. Finally, the meta-analysis included five independent prospective studies of coffee consumption and heart failure risk. Combined, these studies included 6,522heart failure events among 140,220 participants. Four of the studies were done in Sweden and one in Finland. Three studies consisted of participants with no history of myocardial infarction (MI); one consisted of participants with a history of MI, and one included separate analyses for people with and without a history of diabetes or MI.Two

studies included men one included women and two included both men and women.

The researchers found that moderate coffee drinking as part of a daily routine may be linked with a significantly lower risk of heart failure. In contrast, excessive drinking may be linked with an increased chance of developing serious heart problems.

"While there is a commonly held belief that regular coffee consumption may be dangerous to heart health, our research suggests that the opposite may be true," said Dr Murray Mittleman, senior study author.

"We found that moderate consumption — which we define as the equivalent of about two typical American coffee shop beverages — may actually protect against heart failure by as much as 11 percent," he said. "On the other hand, excessive coffee drinking — five to six commercial coffee house cups per day has no benefit and may even be dangerous. As with so many things, moderation appears to be the key here, too."

The study defines moderate consumption as four Northern European servings per day, the equivalent to about two typical 8-ounce American servings. Excessive coffee consumption is 10 Northern European servings per day, the equivalent to four or five coffees from popular American coffee restaurant chains (servings sizes vary from 9 to 20 fluid ounces per serving).

Researchers didn't account for brew strength. Coffee is typically weaker in the United States than it is in Europe. Also they also didn't differentiate between caffeinated and decaffeinated coffee, but most of the coffee consumed in Sweden and Finland is caffeinated.

"There are many factors that play into a person's risk of heart failure, but moderate coffee consumption doesn't appear to be one of them," said Elizabeth Mostofsky, lead study author and research fellow at Beth Israel.

This is good news for coffee drinkers. Ms Mostofsky boldly proposed that their study warrants changes to the current heart failure prevention guidelines, which suggest that coffee drinking may be risky for heart patients.The American Heart Association recommends that heart failure patients consume only a moderate amount of caffeine — no more than a cup or two of coffee or other caffeinated beverage a day.

Researchers didn't definitively say why coffee offers a heart-health benefit. But evidence suggests that frequent coffee drinkers develop a tolerance to the beverage's caffeine, which may put them at a decreased risk of developing high blood pressure.

Habitual coffee consumption is also associated with a lower risk of type 2 diabetes, with most studies showing the greatest reduction in risk with higher levels of coffee consumption.

"Diabetes and hypertension are among the most important risk factors for heart failure, so it stands to reason that reducing one's odds of developing either of them, in turn, reduces one's chance of heart failure," Mittleman said.

Lead glass from TV Tubes could help contain Fukushima radiation

I thought that the headline "TV tubes could help contain Fukushima radiation" in The Asahi Shimbun( June 22, 2012) referred to containing radiophobia rather than radiation.

It was actually more mundane. The  reporter was referring to the use of lead glass from obsolete TV tubes to fortify concrete. It seems that Japan accumulated over 100,000 tons of lead glass from TV tubes.TV tube glass contains 25 % lead.Lead glass is used in TV tubes to shield viewers from x-rays emitted by such tubes. Disposing old TV tubes is a serious solid waste management issue in many countries.

Researchers at Miyagi University have made a container capable of effectively blocking radiation made from concrete blended with lead-laced glass from the TV tubes. Such a practice is not new. Structural engineers  mix  ordinary concrete with iron ore (hematite) to increase its effective density. Denser concrete is more effective as a shielding material.

SHUNSUKE KIMURA, a Staff Writer of  The Asahi Shimbun reported thjat the researchers made a  a prototype container that is 10 centimeters thick and capable of holding 1 cubic meter of soil at a concrete factory in Sukagawa, Fukushima Prefecture, in late May.

The container is almost the same strength as a similarly sized one made of normal concrete and looks similar  but was more effective as a radiation shield. Ordinary concrete has a density of about 2.5 gm per cc. 

A 44-cm-thick slab of the lead-glass concrete is found to be as effective as a shield as a 50 cm ordinary concrete. May be if more lead glass is added, the mix may become weaker. Over all it does not seem to be a big deal, though for those who stored the obsolete TV tubes, the development will be a blessing in disguise. 

Radiation from CT scan from childhood could tripple the risk of leukemia or brain cancer

The Lancet Journal published a paper stating that the radiation exposure received from 2 to 3 computed tomography (CT) scans of the head in childhood (aged under 15 years)—giving a cumulative dose of around 60 mGy— can triple the risk of later developing brain cancer, while around 5 to 10 such scans (cumulative dose around 50 mGy) could triple the risk of developing leukaemia (with the differing number of scans related to different absorption rates of the brain versus the bone marrow and age at time of scanning).
There is some thing unique about this study. The risk estimate in this instance is directly derived. Dozens of such studies are going on all over the world. Normally, the researchers estimated the cancer risks from CT on the basis of risk estimates derived from A-bomb survivors. There were justifiable criticism against this approach.

You can access the paper at:

http://www.thelancet.com/journals/lancet/article/PIIS0140-6736%2812%2960815-0/fulltext

This paper is published Online First by The Lancet on 7 June 2012.

The absolute risk of these cancers occurring after CT is small but there is sufficient reason to keep the radiation doses from CT scans  as low as possible.Dr Mark Pearce and Professor Sir Alan Craft, Newcastle University, UK; Professor Louise Parker, Dalhousie University, Halifax, NS, Canada; Dr Amy Berrington de González, National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD, USA, and colleagues conlude that if appropriate, alternative procedures, that do not use ionising radiation, should be considered.  The study represents the culmination of almost two decades of research in this area, and is jointly funded by the UK Department of Health and NCI/NIH.

CT imaging is a unique medical radiation procedure. Use of this technology has increased rapidly in the USA and elsewhere, especially in the past decade. However, potential cancer risks exist due to the ionising radiation used in CT scans, especially in children who are more radiosensitive than adults.

In this retrospective study, the authors examined the records of close to 180,000 patients who underwent a CT scan between 1985 and 2002. It includes the records from the radiology departments of some 70% of the UK's hospitals. They extracted the number and types of CT scan from the records and estimated the dose absorbed in milli-Grays (mGy) by the brain and bone marrow in patients for each scan.

Then they linked the data to cancer incidence and mortality reports in the UK National Health Service Registry between 1985 and 2008. From this, they calculated excess incidence of leukaemia and brain tumours. The dose of radiation received by the brain and bone marrow varies by age, and body part scanned.

A total of 74 from 178 604 patients were diagnosed with leukaemia and 135 of 176 587 were diagnosed with brain cancer. The authors calculated that the relative risk of leukaemia increased by 0.036 per extra mGy received, whilst for brain tumours this increased risk was 0.023. Compared with patients who received a dose of less than 5 mGy, patients who received a cumulative dose of at least 30 mGy (mean 50 mGy) had around three times the risk of leukaemia.

The  patients receiving a cumulative dose of 50-74 mGy (mean 60 mGy) had triple the risk of developing primary brain tumours. The authors say that, of every 10 000 people between the ages of 0-20 years receiving 10 mGy from a CT scan, there would be about one expected excess leukaemia case, whereas there were would be one excess case of brain cancer for every 30,000 people.

Applying the dose estimates for one head CT scan before the age of 10 years, this would translate into approximately one excess case of leukaemia and one excess brain tumour per 10 000 patients in the decade after first exposure. The authors note that increased follow-up and analysis of other cancer types is needed to identify the total excess risk for all cancers associated with CT scans.

The authors note that, in the UK, the Ionising Radiation (Medical Exposure) Regulations mean that a CT scan should only be done when clinically justified. This might explain the relatively low levels of CT use in the UK compared with other countries that do not have such regulations.

According to the lead author Dr Pearce the immediate benefits of CT outweigh the potential long¬term risks in many settings and because of CT's diagnostic accuracy and speed of scanning, notably removing the need for anaesthesia and sedation in young patients, it will, and should, remain in widespread practice for the foreseeable future.

He argued that further refinements to allow reduction in CT doses should be a priority, not only for the radiology community, but also for manufacturers. Alternative diagnostic procedures that do not involve ionising radiation exposure, such as ultrasound and MRI [magnetic resonance imaging] might be appropriate in some clinical settings. Of utmost importance is that where CT is used, it is only used where fully justified from a clinical perspective.

"It's well known that radiation can cause cancer but there is an ongoing scientific debate about whether relatively low doses of radiation like those received from CT scans do increase cancer risks, and if so the magnitude of those risks. Ours is the first study to provide direct evidence of a link between exposure to radiation from CT in childhood and cancer risk and we were also able to quantify that risk." Dr Berrington de González a co-author added

In a linked comment, Dr Andrew J Einstein, New York Presbyterian Hospital and Columbia University Medical Center, New York, NY, USA, says: "This study should reduce the debates about whether risks from CT are real, but the specialty has anyway changed strikingly in the past decade, even while the risk debate continued. New CT scanners all now have dose-reductions options, and there is far more awareness among practitioners about the need to justify and optimise CT doses—an awareness that will surely be bolstered by Pearce and colleagues' study."

I am not sure that this comment applies to countries such as India.An AERB funded project on CT scan practices in Tamil Nadu revealed that 32 out of the 71 centres do not follow paediatric protocols. Evidently the children undergoing CT exams in these clinics are receiving more doses.

The risk from this practice may be small. But there is no reason why those children should receive unwanted doses. Parents may ask the technologist whether the x-ray centre is following pediatric protocols or not . If they are not ,parents may insist on getting reference to centres where the protocols are followed.

Best of both worlds vacuum -channel transistors

Vacuum tubes have almost completely disappeared from the electronics scene. Semiconductor, the cheaper, lighter, more efficient, and easier to manufacture of the two technologies replaced the old, energy guzzling, bulky cathode ray tubes.
But vacuum tubes have its own virtues. They are more robust in high-radiation environments such as outer space. And since electrons travel faster in a vacuum than through a semiconductor, vacuum tubes are an intrinsically better medium for electricity.
An international team of researchers from NASA's Ames Research Center in Moffett Field, Calif., and the National Nanofab Center in Korea have combined the best traits of both technologies by making a tiny version of vacuum tubes that could be incorporated into circuits. Their prototype, a vacuum channel transistor, is just 150 nanometers long and was made using conventional semiconductor fabrication methods. Its small size allows it to operate at fewer than 10 volts, much less than a retro vacuum tube requires; with further work, the device could be made to use about 1 volt, which would make it competitive with modern semiconductor technology.
In a paper to bw published in the American Institute of Physics' (AIP) journal Applied Physics Letters, the authors write that such a transistor could be useful for applications in hazardous chemical sensing, noninvasive medical diagnostics, and high-speed telecommunications, as well as in so-called "extreme environment" applications for military and space.

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Please lookArticle: "Vacuum nanoelectronics: back to the future? – gate insulated nanoscale vacuum channel transistor," is accepted to Applied Physics Letters.
Authors: Jin-Woo Han (1), Jae Sub Oh (2), and M. Meyya

16 percent of cancers worldwide are are largely preventable or treatable

 
The researchers from the International Agency for Research on Cancer (IARC) used  data from a number of sources including GLOBOCAN statistics on incidence estimates for 27 cancers in 184 countries and  calculated that around 16% of all cancers worldwide in 2008 were infection-related, with the fraction of cancers related to infection about three times higher in developing than in developed countries (22.9% vs 7.4%).

According to the new estimates published in the online First  The Lancet Oncology.,of the 7.5 million deaths from cancer worldwide in 2008, an estimated 1.5 million were due to potentially preventable or treatable infections. 80% of these occur in less developed regions.

"Infections with certain viruses, bacteria, and parasites are one of the biggest and preventable causes of cancer worldwide…Application of existing public-health methods for infection prevention, such as vaccination, safer injection practice, or antimicrobial treatments, could have a substantial effect on future burden of cancer worldwide", explain Catherine de Martel and Martyn Plummer from the IARC France, lead authors of the study.
 
de Martel and colleagues did a systemic analysis to estimate the proportion of cancers that could be attributed to infection globally and in eight regions by calculating the population attributable fractions (PAF)—the proportion of new cancer cases in a population that could have been prevented by an intervention on a specific exposure.

The fraction of infection-related cancers varied widely between regions, from 3.3% in Australia and New Zealand to 32.7% in sub-Saharan Africa.

"Many infection-related cancers are preventable, particularly those associated with human papillomaviruses (HPV), Helicobacter pylori, and hepatitis B (HBV) and C viruses (HCV),", say the authors, adding that these four main infections are together estimated to be responsible for 1.9 million cases, most of which are gastric, liver, and cervical cancers.

Cervical cancer accounted for around half of the infection-related burden of cancer in women, and in men liver and gastric cancers accounted for more than 80%.

The 2011 UN high-level meeting on non-communicable diseases highlighted the growing global agenda for prevention and control of non-communicable diseases. [But] although cancer is considered a major non-communicable disease, a sizable proportion of its causation is infectious and simple non-communicable disease paradigms will not be sufficient.", the researchers concluded.

In an accompanying Comment, Goodarz Danaei from Harvard School of Public Medicine, Boston, USA says: "Their estimates show the potential for preventive and therapeutic programmes in less developed countries to significantly reduce the global burden of cancer and the vast disparities across regions and countries."

"Since effective and relatively low-cost vaccines for HPV and HBV are available, increasing coverage should be a priority for health systems in high-burden countries.", he added



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Low Dose CT useful in staging myeloma

Computed tomography scans get lot of  publicity often because they are used at times indiscriminately. It is a unique diagnostic tool when used in clinically needed examinations. Recently,  researchers have shown that low dose whole body CT is nearly four times better than radiographic skeletal survey, the standard of care in the U.S., for determining the extent of disease in patients with multiple myeloma.

The study, conducted at the University of Maryland in Baltimore, included 51 patients who had both a radiographic skeletal survey as well as a low dose whole body CT examination. The total number of lesions detected in these patients with low dose whole body CT was 968 versus 248 detected by radiographic skeletal survey, said Kelechi Princewill, MD, the lead author of the study.

The study was presented on May 2 at the American Roentgen Ray Society annual meeting in Vancouver, Canada.

 "The stage of disease determines treatment, and the study found that in 31 patients, the stage of disease would have been different with low dose whole body CT. Thirteen patients would have been upstaged from stage I to stage II; nine patients would have been upstaged from stage I to stage III and nine patients would have been upstaged from stage II to III based on additional lesions detected on the low dose whole body CT," said Dr. Princewill.

Low dose whole body CT was significantly better than radiographic skeletal survey in detecting lesions in the spine, ribs, sternum and flat bones, added Dr. Princewill.

In Europe, the use of low dose whole body CT is accepted as an accurate alternative to radiographic skeletal survey for detecting bone lesions in these patients, said Dr. Princewill.

A concern about radiation dose may be one of the reasons why it is not widely accepted in the U.S., he said. "Our study employed a low dose protocol, with an average recorded CT dose of 4.1 mSv. That compares to 1.8 mSv for the radiographic skeletal survey. Using modified protocols and exposure parameters, we were able to significantly reduce the radiation doses to our patients without significantly compromising the image quality required to detect myeloma lesions.

The average CT dose used in our study was approximately nine times lower than doses used in the acquisition of standard body CT studies," Dr. Princewill said.

Radiologists rank themselves as less than competent on health policy issues

 

Radiologists classify themselves as less competent than other physicians regarding knowledge of patient imaging costs and patient safety, a new study shows.The study conducted at Thomas Jefferson University in Philadelphia and Northwestern University in Chicago compared 711 radiologists to 2,685 non-radiology physicians. "On a scale of one to five, with five being highly competent, understanding of patient safety was rated as 3.1 by radiologists and 3.33 by non-radiologists," said Rajni Natesan, MD, an author of the study from Northwestern University. Patient imaging c

 You may access the news item at:
http://www.eurekalert.org/pub_releases/2012-04/arrs-rrt041912.php >

Eat berries and keep your brain sharp

 

 

    

 

 

 

 

 

 

 

 

A new study by researchers at Brigham and Women's Hospital (BWH) finds that a high intake of flavonoid rich berries, such as strawberries and blueberries, over time, can delay memory decline in older women by 2.5 years. This study is published by Annals of Neurology, a journal of the American Neurological Association and Child Neurology Society, on April 26, 2012.

The study subjects were a cohort of 121,700 female, registered nurses between the ages of 30 and 55—who completed health and lifestyle questionnaires beginning in 1976. From 1980 researchers collected details on the frequency of food consumption once every four years. Between 1995 and 2001, memory was measured in 16,010 subjects over the age of 70 years, at 2-year intervals. Women included in the present study had a mean age of 74 and mean body mass index of 26.

Researchers found that increased consumption of blueberries and strawberries was associated with a slower rate of memory decline in older women. Greater the intake of anthocyanidins and total flavonoids lesser was the memory decline. The reduction was moderate among women who consumed 2 or more servings of strawberries and blueberries each week It seems that the effect was attainable with relatively simple dietary modifications .The study was unique as it was of such a large scale and over a long period of time. Whether the beneficial effect of regular consumption of berries will be seen in men is not known. Berries are rich; it is worthwhile making it a part of every day diet. 

"Our findings have significant public health implications as increasing berry intake is a fairly simple dietary modification to reduce memory decline in older adults" Elizabeth Devore in the Channing Laboratory at BWH the lead researcher of the study noted.

http://www.eurekalert.org/pub_releases/2012-04/bawh-bky042512.php