Wednesday, December 20, 2006

A New Potential Weapon against TB

A team of researchers from University of Wisconsin-Madison School of Veterinary Medicine, Texas A&M University, and University of Saskatchewan in Saskatoon, Canada has discovered a unique copper-repressing protein in the bacterium that causes tuberculosis in humans. This finding could pave the way for new strategies to halt tuberculosis infection.

When TB bugs invade, host immune cells dump excessive amounts of copper onto the invaders in an effort to kill them. Though all cells need copper, but too much of it causes cell death. But the present study has found that the TB bugs fight back by generating a copper-repressing protein. This helps the TB bugs block excess copper in host’s body. With this discovery, we can now pursue ways to deactivate the repressor protein leading to novel antidote to tuberculosis infection, say the researchers in a paper that will appear in January 2007 issue of Nature Chemical Biology.

Tuesday, December 05, 2006

A Vaccine for Ebola Virus is Safe in Healthy Adults

A DNA vaccine for Ebola virus was found to be safe in healthy adults, according to a study published in the November issue of journal Clinical and Vaccine Immunology. The vaccine developed by a research team from Vaccine Research Centre at National Institute of Allergy and Infectious Diseases, Bethesda, Maryland and Statistical Center for HIV/AIDS Research and Prevention, Fred Hutchinson Cancer Research Center, Seattle, Washington was well-tolerated, with no significant adverse events or coagulation abnormalities.

Since 1976, Ebola virus has been spreading panic in developing countries of Africa like the Democratic Republic of the Congo (formerly Zaire) and Sudan. In recent years, it (especially Ebola-Zaire subtype) has surfaced in Uganda, Gabon and The Republic of Congo. This virus is deadly as it causes death in 50 and 90 per cent of all clinically ill cases.


The vaccine encoding the envelope glycoprotein (GP) from the Zaire and Sudan/Gulu species of Ebola virus as well as nucleoprotein was administered to 21 adults aged between 18 and 44. Each healthy volunteer received three injections of the vaccine. Of them, five received at a dose of 2 mg, 8 at 4 mg and 8 at 8 mg and these vaccinated adults were compared with 6 placebo subjects. The treated group showed specific antibody responses as well as generation of lymphocytes (CD8+ T-cell and CD4+ T-cell), a type of white blood cells, which are capable of killing the whole virus and help generate antibodies in response to GP of Ebola virus.

The lurking threat is the natural reservoir of the Ebola virus, which seems to reside in the rain forests of the African continent and in areas of the Western Pacific. On the African continent, Ebola infections of human cases have been linked to direct contact with gorillas, chimpanzees, monkeys, forest antelope and porcupines found dead in the rainforest. So far, the Ebola virus has been detected in the wild in carcasses of chimpanzees (in Côte-d’Ivoire and Republic of Congo), gorillas (Gabon and Republic of Congo) and duikers (Republic of Congo).

As any time, humans can come into contact with this natural reservoir during their day-to-day activities, most of which revolve around forest and wild life. No specific treatment or vaccine is yet available for Ebola haemorrhagic fever. Several vaccine candidates are being tested but it could be several years before any are available. The present study which highlights the safety of a DNA vaccine for Ebola virus, which has wreaked havoc in recent years, is very important and encouraging for developing countries in Africa as well as Asia.

Saturday, December 02, 2006

Moon: Dead or Alive?

If you are with conventional wisdom that any volcanic activities on the moon have ceased billions of years ago, then you are mistaken. A new study points to evidence that the moon has been geologically active within the past 10 million years. The site that bears the signs of recent geological activities is ‘Ina’, in Lacus Felicitatis, a lake of ancient, hardened lava located at lunar coordinates 19o N, 5o E, according to a report published in the 9 November issue of journal Nature.

Apollo astronauts first noticed Ina. Since then it became the object of intense scrutiny of astronomers. “It is shaped like a letter D and two kilometers wide,” says Peter Schultz of Brown University in US, who led the research team in uncovering the mysteries of Ina. Several features of Ina prove that it is young. One of them is that Ina has sharp edges. As small meteoroids constantly rain down on the moon’s surface, sharp edges are unlikely to survive. Further, Ina is sparsely cratered. According to Schultz, there are only two clear impact craters larger than 30 meters on the 8 square kilometers of the structure’s floor.

Schultz and his teammates found that patches of lunar regolith in the Ina structure were recently removed. “The number of superimposed small craters and the freshness of the regolith together indicate that features within this structure must be very young and perhaps are still forming today,” concludes Schultz.