Month: April 2006

A Cadmium Conundrum

How do you clean up waste water contaminated with the deadly metal cadmium and what do you do with the resulting material? French scientists reckon they have found the answer.

The mineral hydroxyapatite, like its natural counterpart found in tooth and bone, has an affinity for the toxic heavy metal cadmium, they say. Now, they have used X-ray diffraction spectroscopic analysis, and electron microscopy to follow the kinetics of uptake and release of this metal from hydroxyapatite and have demonstrated that a solid apatite solution of cadmium is formed. Their findings could have implications for the dual use of this material as a decontaminant and a storage medium for cadmium.

Read on…

Improved Biological Imaging

French researchers have now demonstrated a way to circumvent one of the main problems associated with cellular imaging and can obtain nanomolar concentration readings even for complex biological samples using their approach.

The method has led to an extension of the use of spectroscopy and spectro-imaging to many more parameters associated with cellular activity in both cultured and xenografted cells, and living tissues. No other analytical technique is available that can analyse tissue sections without embedding, fixation, or reagents adding, at the resolution and sensitivity obtained by the team.

Read on…

Traditional Chinese Medicine Analyzed

Huángqí (huangqi) is a plant root used in one of the most common tonics of Chinese traditional herbal medicine with purported activity in cancer, diabetes, inflammation, and nephritis.

As such, there is a lot of interest in the active ingredients of this species as it might lead to novel pharmaceuticals against a range of illnesses. Now, researchers in China have used a powerful spectroscopic technique to identify the active chemical components of this remedy.

Read more…

Greener Toxic Metal Analysis

Improving detection of toxic metals in the environment and trace elements in medical samples is often time-consuming and, worse, reagent demanding, as well as potentially having false positives as samples become contaminated by pre-treatment.Portuguese researchers have now overcome these drawbacks by using an online sample pre-treatment method.

The team has coupled an online high-intensity focused ultrasound system with a more conventional analytical technique, which they say is greener than conventional approaches because it needs less reagents but more importantly avoids contamination and cuts the amount of time taken to analyse metals such as mercury in water and urine samples. The approach should be generally applicable, the researchers say. You can read the full analysis of this research in the latest news round up from David Bradley at spectroscopyNOW.com

Sudoku to Beat Schizophrenia

Jennifer Barnett and researchers at the University of Cambridge’s Department of Psychiatry have discovered that intelligence can reduce the effects and severity of schizophrenia, bipolar disorder, depression, and other neuropsychiatric disorders.

It was already known that intelligence can protect against dementia and the effects of head injury. Now, Barnett and her colleagues have reviewed the literature to discover that intelligence can also act as a buffer against the potentially debilitating effects of schizophrenia and other disorders. They found that for people with a higher IQ, the symptoms of schizophrenia were less severe and the ability to function in daily life better than for those people of lower IQ.

The team found that a phenomenon known as “cognitive reserve” made people more resilient to disabilities arising from these disorders. Fortunately, cognitive reserve can be strengthened through education, neurocognitive activation (doing sudoku, crosswords, and other puzzles), or other treatment programs. It may also be possible to improve cognitive reserve through the use of cognition-enhancing drugs, say the researchers.

“Cognitive reserve may greatly improve our understanding of individual differences in the causes and consequences of schizophrenia and other neuropsychiatric disorders,” Barnett explains. Team leader Barbara Sahakian adds that “We are very excited about these novel results. We have known for some time that it is important to ‘use it or lose it’ with regard to ageing and dementia, but it now seems that this concept applies more widely.”

The research will appear online in the journal Psychological Medicine

You can play suduko online at Sciencebase.

Terrorist Detector

Researchers in the US have developed an exquisitely sensitive test, better by a thousand-fold than previous efforts, for detecting trace quantities of cholera and botulinum toxins. These two agents are considered potential agents of a bioterrorist attack. Their test takes just three hours to provide a result.

Until now, the most rapid and sensitive approach to biotoxin detection has involved coupling the polymerase chain reaction (PCR) with antibody specificity for toxins.

To boost the sensitivity of this approach, Jeffrey Mason and colleagues at the Armed Forces Institute of Pathology, Rockville, MD, package about sixty molecules that initiate PCR into a hollow liposome decorated with receptors for the toxin. When present, the toxin binds to the receptors, and when the liposome is subsequently broken open, the released PCR-initiating molecules amplify the signal and enable detection of vanishingly small amounts of toxins – they are detectable even against a background of harmless components in urine and runoff water.

The team reports details of its new test in Nature Biotechnology today.

Antibiotics for asthma

Researchers at Imperial College London have demonstrated that an antibiotic is effective at treating acute asthma attacks, potentially providing a new way to help asthma sufferers.

The team found that the antibiotic, telithromycin, can hasten the recovery time of patients who have had asthma attacks by three days, as well as reducing their symptoms and improving lung function. Treatment for some serious asthma attacks can involve the use of steroids, which help control inflammation of the lungs and bronchodilators to open airways. However, telithromycin, an antibiotic was tested as part of the TELICAST (TELIthromycin, Chlamydophila and ASThma) study on 278 patients at 70 centres around the world, including St Mary’s Hospital, London to see whether asthma therapy could be added to the drug’s repertoire.

The patients were enrolled in the study within 24 hours of an acute asthma attack requiring acute medical care. They were then randomised double blind to either ten days oral treatment with a single 800mg dose of telithromycin daily, or placebo in addition to usual treatment. Symptoms and lung function for the patients in the telithromycin group improved significantly compared to those in the placebo group, with improvements being around twice as great at the end of the treatment period. Recovery time was also cut from an average of eight days for the placebo group, to five days for those in the telithromycin group.

Sebastian Johnston from Imperial College London, who led the research, said: ‘Traditionally antibiotics have not proven effective in treating asthma attacks, but this development could open up a whole new area of research in the treatment of asthma.”

Stars of CCTV Spotted Carrying Guns

A system that can help CCTV operators identify people carrying concealed guns is being developed at Loughborough University. The MEDUSA (Multi Environment Deployable Universal Software Application) project will help reduce gun crime by providing software that can analyse CCTV images and report whether people in the frame, are in the frame. The system will work in in real time allowing the police to grab anyone toting a gun before a serious crime is committed.

The research team will examine genuine CCTV footage of people carrying concealed firearms, to identify any characteristics which are associated with the behaviour and activity of criminals before they commit a gun associated crime. This could be body stance/shape, movement or eye contact with cameras. Using this information they will then develop a novel machine-learning system for behavioural interpretation. This software will enable CCTV camera systems to automatically scan footage, searching for any behavioural characteristics which indicate that an individual may be carrying a gun and, if necessary, alert CCTV operators.

The researchers will also develop a training programme for CCTV operators to enable them to improve their ability to detect suspicious characters. For this they will meet with experienced operators and identify the key cues they already utilise to detect people carrying concealed weapons, and then make these available for training purposes. A detailed database of CCTV footage of individuals carrying or not carrying concealed firearms will also be generated, which can then be used by local authorities and the police for training CCTV operators in what to look for. Alastair Gale, Head of Loughborough University’s Applied Vision Research Centre is leading the MEDUSA project: “The primary aim of this research is to make the UK a safer place to live by reducing the occurrence of gun crime,” he says, “To do this we need to develop ways of identifying a potential gun crime before an incident occurs – a key instrument in this is CCTV.”

The new software will significantly improve CCTV systems enabling individuals to be apprehended before they commit a crime. As the CCTV infrastructure is already in place it should be relatively easy to implement MEDUSA. Its introduction would also lead to the more efficient use of police time, as well as more socially acceptable police practices as the identification of potential criminals becomes improved. Additionally, the system will yield faster post-event analysis of CCTV footage.

Pox Virus Undressed to Make its Entry

Geoffrey Smith of Imperial College London and colleagues have discovered how Vaccinia, the smallpox vaccine, enters cells and causes infection. The findings shed light on a novel mechanism by which active pox viruses can infect people. Apparently, the Vaccinia virus sheds its outer lipid membrane to enter cells. This naked entrance mechanism is unique in virology and could pave the way for a range of new antiviral drugs.

Many viruses, such as the H5N1 avian influenza virus, are surrounded by a single lipid membrane, or envelope. To enter cells this membrane has to be shed. Previously, all enveloped viruses were thought to shed their lipid membrane by fusion with a cell membrane which allows the viral core to be released into the cell.

In contrast, the extracellular form of Vaccinia virus has two lipid membranes, meaning a single fusion event will not release a naked virus core into the cell. The Imperial team has found that interactions between negatively charged molecules on the cell surface and sugar-linked proteins, glycoproteins, on the virus’ surface split the virus outer envelope without fusing, allowing the poxvirus to enter the cell.

As well as discovering how the double membrane problem is solved, the researchers demonstrated that these multiply charged, polyionic, compounds can destroy the poxvirus even days after infection has started. Disrupting the outer membrane with polyanionic compounds exposes the virus, allowing antiviral antibodies to be more effective. The disruption of the outer membrane also limits the spread of the virus in the body.

“This work has uncovered a completely novel biological process,” Smith, “It increases our understanding of how viruses can manipulate biological membranes and will help the development of new drugs against poxviruses, such as variola virus, the cause of smallpox.”

Details in Proc Nat Acad Sci

scenta volcano news

I recently wrote about the Tunguska meteorite and its putative impact on the global climate, but there are also the effects of volcanoes to consider.

According to a recent posting on the scenta volcanoes news page at Sciencebase, The eruption of Pinatubo in 1991 led to a cooling of the Earth of 0.5 Celsius, while the eruption of Mount Tambora led to 1815 being labelled as the “Year Without Summer” leading to great crop failures worldwide. Check out the scenta volcanoes site for more on this and other volcanic news.