New enzyme to combat deadly toxic agents


New enzyme to combat deadly toxic agents
Experts have developed an enzyme treatment that could offset the effects of lethal chemicals that kill hundreds of thousands of people globally.
LONDON: Experts have developed an enzyme treatment that could offset the effects of lethal chemicals that kill hundreds of thousands of people globally.

Organophosphorus agents (OP) are used as pesticides in developing countries and acute poisoning is common because of insufficient control, poor storage, ready availability, and inadequate education amongst farmers.

OPs include compounds like Tabun, which was developed in 1936 by German scientists during World War II, Sarin, Soman, Cyclosarin, VX, and VR, the journal Proceeding of the National Academy of Sciences reports.

Worldwide about 200,000 people are estimated to die every year from OP poisoning, through occupational exposure, unintentional use and misuse, mostly countries like India, Pakistan, and Sri Lanka and through deliberate terror activities.

Using a modified human enzyme, Mike Blackburn, professor of molecular biology at the University of Sheffield, tied-up with Alexander Gabibov, professor at the Shemyakin-Ovchinnikov Institute, Moscow, and Patrick Masson of the Departement de Toxicologie, Centre de Recherches du Service de Sante des Armees, to create a "bio-scavenger".

The bio-scavenger was found to protect mice against the nerve agent VR and showed no lasting effects, according to a Sheffield statement.

In studies performed at the Institute of Bio-organic Chemistry in Pushchino, Russia, a group mice was treated with the new enzyme after being subjected to enough of the VR agent to kill several of the animals - about 63 mg - and all survived.

"This current publication describes a novel method to generate a bio-scavenger for the Russian VR organophosphorus agent with the key property of being long-acting in the bloodstream," said Blackburn.

Google search algorithm helps track spread of cancer


Google search algorithm helps track spread of cancer
Google ranks webpages by the likelihood that an individual would end up visiting each one randomly.
NEW YORK: The equations search engine Google employs to predict the webpages its users visit has inspired a new way to track the spread of cancer cells in the human body.

"Each of the sites where a spreading, or metastatic, tumour could show up are analogous to Web pages," said Paul Newton, a mathematician at University of Southern California.

Google ranks webpages by the likelihood that an individual would end up visiting each one randomly. These predictions are based on the trends of millions of users across the Web, the 'Live Science' reported.

It uses the "steady state distribution" to calculate the probability of someone visiting a page.

"You have millions of people wandering the Web, [and] Google would like to know what proportion are visiting any given Web page at a given time.

"It occurred to me that steady state distribution is equivalent to the metastatic tumour distribution that shows up in the autopsy datasets," Newton said.

The referred dataset contains information about autopsy patients from the 1920's to the 1940's, who died before chemotherapy was available.

By focusing on this group of patients, the researchers could track the natural progression of cancer, specifically lung cancer, without different treatments interfering with the data.

Out of fifty metastasis sites described in the autopsy reports, the scientists found that twenty-seven contained cancer that appeared to have spread from the lungs.

Just like with an individual browsing the Web, cells that break off from the original lung tumour and entered the bloodstream had a certain probability of progressing to different locations.

Following the Google's example with search results, the researchers split the sites where the lung cancer spread to into two groups into first and second order.

In first order sites, tumour cells would most likely reach them by travelling directly from the lung. Tumours are more likely to reach second order sites by colonising a first order site and then spreading to the second order location.

Researchers, using this approach, were even able to estimate the average times it takes the cancer to spread to different parts of the body, the report said.

New tech helps spot cancer spread


New tech helps spot cancer spread
Lymph nodes, located throughout the body, serve as filters that contain immune cells to fight infection and clean the blood. When cancer cells break away from a tumour, the cells can travel through the lymph system and hide in these tiny organs.
WASHINGTON: Researchers have developed a new technique that will allow surgeons to identify how far the tumour has spread and help them decide which tissue to remove in order to save healthy cells in cancer patients.

"With molecular-targeted imaging, surgeons can avoid unnecessary removal of healthy lymph nodes which is better long-term for patients," said Quyen T Nguyen, associate professor at University of California, San Diego School of Medicine. "The range of the surgeon's visual field is greatly enhanced by a molecular tool that can help achieve accurate surgical margins and detection of metastases so that no tumour is left behind," Nguyen said.

Lymph nodes, located throughout the body, serve as filters that contain immune cells to fight infection and clean the blood. When cancer cells break away from a tumour, the cells can travel through the lymph system and hide in these tiny organs.

Surgeons remove the nodes to determine if a cancer has spread. However, human nodes, only half a centimetre in size, are difficult to discern among the surrounding tissue during surgery.

Furthermore, even when surgeons are able to map the location of the nodes, there is no current technique that indicates whether or not the lymph nodes contain cancer, requiring removal of more lymph nodes than necessary.

"This research is significant because it shows real-time intra-operative detection of cancer metastases in mice. In the future, surgeons will be better able to detect and stage cancer that has spread to the patient's lymph nodes using molecules that were designed and developed at UC San Diego," he said.

The fluorescently labelled molecules, known as ratio-metric activatable cell-penetrating peptides ( RACPP), are injectable. When used in mouse models, surgeons could see where the cancer had spread with high sensitivity and specificity even when the metastatic sites were only a few millimetres in size.