Chem News

Wednesday, October 8, 2014

Nobel Prize in Chemistry

Surpassing the limitations of the light microscope

For a long time optical microscopy was held back by a presumed limitation: that it would never obtain a better resolution than half the wavelength of light. Helped by fluorescent molecules the Nobel Laureates in Chemistry 2014 ingeniously circumvented this limitation. Their ground-breaking work has brought optical microscopy into the nanodimension.

In what has become known as nanoscopy, scientists visualize the pathways of individual molecules inside living cells. They can see how molecules create synapses between nerve cells in the brain; they can track proteins involved in Parkinson’s, Alzheimer’s and Huntington’s diseases as they aggregate; they follow individual proteins in fertilized eggs as these divide into embryos.

It was all but obvious that scientists should ever be able to study living cells in the tiniest molecular detail. In 1873, the microscopist Ernst Abbe stipulated a physical limit for the maximum resolution of traditional optical microscopy: it could never become better than 0.2 micrometres. Eric Betzig, Stefan W. Helland William E. Moerner are awarded the Nobel Prize in Chemistry 2014 for having bypassed this limit. Due to their achievements the optical microscope can now peer into the nanoworld.

Two separate principles are rewarded. One enables the method stimulated emission depletion (STED) microscopy, developed by Stefan Hell in 2000. Two laser beams are utilized; one stimulates fluorescent molecules to glow, another cancels out all fluorescence except for that in a nanometre-sized volume. Scanning over the sample, nanometre for nanometre, yields an image with a resolution better than Abbe’s stipulated limit.

Eric Betzig and William Moerner, working separately, laid the foundation for the second method, single-molecule microscopy. The method relies upon the possibility to turn the fluorescence of individual molecules on and off. Scientists image the same area multiple times, letting just a few interspersed molecules glow each time. Superimposing these images yields a dense super-image resolved at the nanolevel. In 2006 Eric Betzig utilized this method for the first time.

Today, nanoscopy is used world-wide and new knowledge of greatest benefit to mankind is produced on a daily basis.

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Tuesday, October 7, 2014

Enterovirus 68

The rapid, nationwide spread of the enterovirus 68 respiratory infection is unlike any previous outbreak of the disease public health officials have seen.

As of this week, the Centers for Disease Control and Prevention have confirmed nearly 500 cases of the infection, including four in patients who died, although it’s uncertain what role the virus played in their deaths. Experts say the true number of cases is likely much higher, since only a fraction of patients suspected of having the infection have been tested, and the infection is usually neither fatal nor severe.

Most of the patients seriously affected are children. Experts say thatparents should be on the lookout for children with difficulty breathing, chest pain, wheezing or blue lips. Those are signs that the child requires immediate medical care. Children with asthma and other chronic lung conditions are particularly vulnerable.

Until recently a lot of people had never heard of enterovirus 68. Is this outbreak — or the scope of it — unusual?

I think the most surprising aspect of it is how severe it is, particularly the symptoms in kids. Because that hasn’t really been seen before. As far as the extent of it, in the past 10 years, there have been reports by our group as well as several around the world that the virus has been increasing in incidence. There have been clusters in Southeast Asia, in Europe, in Africa and in North America. It’s been increasing in the past decade.

What is different about the symptoms seen in this outbreak compared to previous clusters?

In most cases it manifests itself as a cold or maybe a mild case of the flu, and it probably got diagnosed as such. I believe in a lot of cases it’s still no different than a severe cold or the flu, even during this outbreak. But in certain individuals the symptoms are more severe, and that hasn’t been seen before. What’s different now is that kids are going to the I.C.U. But the fact is that we don’t know a lot about this virus. Until the last 10 years or so it was very rare.

Why is this outbreak so different than others? Is the virus evolving?

Absolutely. It is evolving. A hypothesis of mine is that the strain that’s circulating now probably is a novel variant. It may have mutated into something that’s more easily transmissible and more pathogenic. The virus is mutating, and there are a lot of different variants circulating around the globe.

We don’t know much about this particular strain because that data to my knowledge hasn’t been released yet by the Centers for
Disease Control and Prevention. But enteroviruses do change over time fairly rapidly. If you look at the strains that were circulating in the past, the strains from 10, 15 or 20 years ago, they’re very different genetically.

Why is this outbreak so much more widespread than previous ones?

A.I would guess that the strains that are circulating now are basically more transmissible. They can be spread more easily from person to person – maybe more infectious. That’s something we won’t know until we can compare the strains circulating now to earlier strains. So we won’t know that for a while.

Some studies suggest that in the past, enterovirus 68 may have been commonly overlooked or mistaken for similar infections, like the common cold. Is that true?

It definitely was under-reported. It’s likely there had been more cases last year and many of them were missed because enterovirus was not something one would immediately think of since the virus was so rare.

This is really the first time there’s been such a large outbreak with severe symptoms. But in the past, there have been clusters in the United States. We discovered a cluster in New York City in 2009. There were clusters documented across the United States in 2009 and 2010. So there have certainly been clusters of this virus in the past but what is different now is the scale and the symptoms.

The outbreak this year is largely affecting children. Is that typical of enterovirus?

In most cases, yes. It’s always been associated predominantly with children – probably because they show more symptoms. But it has been reported in adults as well. There have been cases in adults documented here in the United States and in Asia as well. It affects adults as well, but with less severe symptoms.

Ill: N. Elmehed. © Nobel Media 2014

2014 Nobel Prize in Physics

The Nobel Prize in Physics 2014 was awarded jointly to Isamu Akasaki, Hiroshi Amano and Shuji Nakamura "for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources".

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Monday, October 6, 2014

Nobel Prize for Our Inner GPS

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Friday, October 3, 2014

Modified aubergines could transform farming in India

STAND by your bhajis. The humble aubergine – you might call it eggplant or brinjal – may be about to unlock a food revolution across Asia. It is a revolution that could dramatically raise yields of staple foods while cutting farmers' deaths from pesticide spraying. And it could be coming to a curry house near you.

I'm in New Delhi to hear from Indian scientists about what's in store. Many believe their government is preparing to abandon a four-year moratorium on trials of a genetically modified form of one of south Asia's favourite vegetables, which could rapidly take over from non-GM varieties. Since science-friendly Narendra Modi swept to power in India's elections in May, the government's Genetic Engineering Approval Committee (GEAC) has been reactivated. If genetically modified aubergines get the green light, they would join a select number of modified plants, including papayas and squashes, that are grown primarily for human consumption. GM soya beans and maize are in the human food chain, but they are mainly grown for animals.

The modified aubergine in question is known as Bt brinjal, and contains a gene taken from a common soil bacterium, Bacillus thuringiensis. The gene produces a toxin that kills the vegetable's main pest, the larvae of the fruit and shoot borer moth, and was first promoted by seed giant Monsanto for protecting cotton against bollworm. The company agreed to donate the gene free for brinjal.

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An attraction for farmers is that they are permitted to propagate Bt brinjal using their own seeds, which isn't the case with many modified crops (particularly Bt cotton), which are owned by biotech firms.

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Fending off the fruit and shoot borer requires almost daily spraying with pesticides that are dangerous and expensive. Bt brinjal promises to largely remove the need for spraying against the borer, although other pesticides will still be needed.

Tests have shown that the Bt gene is harmless to humans and animals when eaten and is unlikely to threaten wild relatives of brinjal (see "In the public eye"). Its incorporation in Indian cotton cultivation has more than doubled yields.

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Thursday, October 2, 2014

Kid Cuisine Limited Edition How to Train Your Dragon Chicken Nuggets Video Review (Ep692)

Tasting starts at 3:30

U.S. Will Increase Production of the Ebola Drug ZMapp, but May Not Meet Demand

Proteins glowing under ultraviolet light on a type of plant used to produce the drug ZMapp.

Federal officials are planning to sharply increase production of ZMapp, which is viewed by many experts as the most promising experimental drug for treating people infected with Ebola in West Africa.

The Department of Health and Human Services is in advanced discussions to enlist Caliber Biotherapeutics, a Texas company that can produce the drug in millions of tobacco plants, according to federal officials and pharmaceutical industry executives.

Federal officials, along with two of the world’s biggest charities — the Bill & Melinda Gates Foundation and theWellcome Trust — are also looking at arranging for production of ZMapp in animal cells, the more conventional method used by the biotechnology industry. Although that would take longer, it would allow for greater output by tapping into the biotechnology industry’s huge production capacity. ...

Despite the new efforts, supplies of the drug are expected to be limited to hundreds or thousands of treatment courses by early next year, which would not be nearly enough if the epidemic continues to spiral out of control.

MAKENI, Sierra Leone — “Where’s the corpse?” the burial-team worker shouted, kicking open the door of the isolation ward at the government hospital here. The body was right in front of him, a solidly built young man sprawled out on the floor all night, his right hand twisted in an awkward clench.

The other patients, normally padlocked inside, were too sick to look up as the body was hauled away. Nurses, some not wearing gloves and others in street clothes, clustered by the door as pools of the patients’ bodily fluids spread to the threshold. A worker kicked another man on the floor to see if he was still alive. The man’s foot moved and the team kept going. It was 1:30 in the afternoon.

In the next ward, a 4-year-old girl lay on the floor in urine, motionless, bleeding from her mouth, her eyes open. A corpse lay in the corner — a young woman, legs akimbo, who had died overnight. A small child stood on a cot watching as the team took the body away, stepping around a little boy lying immobile next to black buckets of vomit. They sprayed the body, and the little girl on the floor, with chlorine as they left.

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