TOP 100 SCIENCE SITES
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| EO Wilson on the 'immense and hidden' crisis in biodiversity This is an extended extract of a phone interview with biologist, author and conservation campaigner EO Wilson. The problem of biodiversity loss has been "eased off centre stage" as the spotlight has focused on climate change, according to Professor Edward Wilson, the ecologist described as "Darwin's natural heir". Biodiversity is one of the hot topics of conversation on this week's regular Science Weekly podcast. Professor Wilson also discusses conservative religious attitudes to evolution in the US, which he calls "bible literalism". Post your comments below.Join our Facebook group. Listen back through our archive.Follow the podcast on our Science Weekly Twitter feed and receive updates on all breaking science news stories from Guardian Science.Subscribe free via iTunes to ensure every episode gets delivered. (Here is the non-iTunes URL feed).James Randerson guardian.co.uk |
More could get vCJD than thought More people may be incubating variant CJD, the human version of so-called "mad cow disease", than was previously thought, according to scientists who today report an unusual case of the disease. All those tested worldwide since 1994 when the first cases were identified have been MM homozygous.However, a 30-year-old man who died of vCJD in January this year was found to have a different genetic makeup from the rest of the 200 or so people diagnosed around the world. Six months before the man was diagnosed with the disease, he had been admitted to hospital with personality changes, unsteadiness in walking that became progressively worse and intellectual decline. He told doctors he had severe leg pain and memory problems. Two months later, he developed visual hallucinations. The symptoms got progressively worse and an MRI scan confirmed vCJD. The symptoms and the course of the illness were not unusual for vCJD, but the man had a different genetic makeup from the rest of the 200 or so people diagnosed around the world to date.Variant CJD is caused by prions, infectious agents which are made up mainly of proteins. The same prions cause vCJD and also BSE - bovine spongiform encephalopathy - which was dubbed "mad cow disease" because cattle who contracted it staggered when they tried to walk. Prion diseases affect the structure of the brain or other neural tissue and are currently untreatable and fatal.Doctors from the MRC Prion Unit and National Prion Clinic at the UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery in London, report the unusual case in today's Lancet medical journal. Tests showed that the man had a particular form of the human prion protein gene. All those tested world-wide since 1994 when the first cases were identified have been MM homozygous. However, this patient was MV heterozygous.The observation could be of concern. In some other human prion diseases, such as kuru - thought to be linked to cannibalism in Papua New Guinea - people who are MV heterozygous have incubated the disease for longer than those who are MM homozygous before symptoms have shown. Some MV heterozygous patients are reported to have incubated kuru for over 50 years.It is possible, doctors say, that vCJD takes longer to develop in people who are MV heterozygous than in MV homozygous people."The majority of the UK population have potentially been exposed to BSE prions but the extent of clinically silent infection remains unclear," say the authors of the paper. About a third of the population have the MM homozygous genotype - and until now all the cases came from this group. If individuals with other genotypes are similarly susceptible to developing prion disease after exposure to BSE, further cases would be expected, they say. However, they add, it is possible that susceptibility to vCJD and incubation period may be influenced by other genetic factors which have not yet been identified.NeuroscienceGeneticsMedical researchBiochemistry and molecular biologyHealthHealth & wellbeingSarah Boseleyguardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
'Bumper year' for botanical finds Almost 300 species - including giant trees and tiny fungi - have been described for the first time by UK botanists in 2009. news.bbc.co.uk |
Managing Disasters With Small Steps Some innovative organizations are involving local people in building or rebuilding infrastructure in developing countries. feeds.nytimes.com |
Resurgence of rickets in UK Sharp rise in problem blamed on kids indoors playing computers and parents using too much sunscreenComputer-obsessed children who spend too long indoors and over-anxious parents who slap on excessive sunscreen are contributing to a sharp rise in cases of the bone disease rickets, doctors are warning.Vitamin D deficiency, which causes the condition, could be rectified by adding supplements to milk and other food, a research team at Newcastle University suggests.There are several hundred cases of the preventable condition among children in the UK every year, according to a clinical review paper in the British Medical Journal by Professor Simon Pearce and Dr Tim Cheetham."More than 50% of the adult population [in the UK] have insufficient levels of vitamin D and 16% have severe deficiency during winter and spring," they say. "The highest rates are in Scotland, Northern Ireland and northern England. People with pigmented skin are at high risk as are the elderly, obese individuals and those with malabsorption."Most vitamin D is synthesised in the body by absorption of sunlight. Some comes from foods such as fish oil. People with darker skins need more sunlight to top up their vitamin D levels.One of the main reasons for the reappearance of rickets – once considered a disease of the industrial poor in 19th-century cities – is the changing ethnic makeup of the population, Pearce explained.The most commonly affected are people of Asian or African descent who live in northern cities. He has examined cases among young Somali speakers who live in east Newcastle. But changing lifestyles are also contributing to lowering vitamin D levels in the general population."Some people are taking the safe sun message too far," Pearce said. "It's good to have 20 to 30 minutes of exposure to the sun two to three times a week, after which you can put on a hat or sunscreen."Vitamin D levels in parts of the population are precarious. The average worker nowadays is in a call centre, not out in the field. People tend to stay at home rather than going outside to kick a ball around. They stay at home on computer games."Pearce has written to the Department of Health proposing that vitamin D is added to milk. It is already added as a supplement to artificial baby milk. He has also asked the Royal College of Paediatrics to record cases of rickets but said figures were not being collected."A more robust approach to statutory food supplementation with vitamin D (for example in milk) is needed in the UK," the paper concludes.Meanwhile, figures obtained by the Tories show the number of patients leaving hospital with malnutrition has hit record levels in the last year. Those affected are primarily elderly people. The NHS figures show that last year 175,000 people were malnourished on entry to hospital but nearly 185,500 were in a similar condition on discharge, meaning more than 10,000 patients were more malnourished after medical treatment.HealthGame cultureChildrenNutritionNutritionMedical researchOwen Bowcottguardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |