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Latest Proceedings of the National Academy of Sciences Stories

2014-05-07 08:54:14

Each time a human cell divides, it must first make a copy of its 46 chromosomes to serve as an instruction manual for the new cell. Normally, this process goes off without a hitch. But from time to time, the information isn't copied and collated properly, leaving gaps or breaks that the cell has to carefully combine back together. Researchers have long recognized that some regions of the chromosome,called "fragile sites," are more prone to breakage and can be a breeding ground for human...

2014-05-07 08:45:28

A new study led by scientists at the University of Pennsylvania School of Veterinary Medicine has painted a clearer picture of the delicate arms race between the human immune system and a pathogen that seeks to infect and kill human cells. The research explores the strategies by which the bacterial pathogen Yersinia, responsible for causing plague and gastrointestinal infections, tries to outsmart immune cell responses and looks at the tactics used by the immune system to fight back....

2014-05-06 15:07:45

Populations of predators and their prey usually follow predictable cycles. When the number of prey increases, perhaps as their food supply becomes more abundant, predator populations also grow. When the predator population becomes too large, however, the prey population often plummets, leaving too little food for the predators, whose population also then crashes. This canonical view of predator-prey relationships was first identified by mathematical biologists Alfred Lotka and Vito...

2014-05-02 10:06:07

Enzyme's double-edged sword may soon be sheathed Johns Hopkins biochemists have figured out what is needed to activate and sustain the virus-fighting activity of an enzyme found in CD4+ T cells, the human immune cells infected by HIV. The discovery could launch a more effective strategy for preventing the spread of HIV in the body with drugs targeting this enzyme, they say. A summary of their work was published online on April 21 in the journal Proceedings of the National Academy of...

2014-04-10 16:15:29

New findings hold promise for expanded use of bioluminescence imaging tools New research from scientists at the University of Massachusetts Medical School shows that fruit flies are secretly harboring the biochemistry needed to glow in the dark —otherwise known as bioluminescence. The key to activating this latent ability is a novel synthetic analog of D-luciferin developed at UMMS. The findings, published in the journal Proceedings of the National Academy of Sciences, suggest that...

2014-04-08 11:51:42

From time to time, living cells will accidentally make an extra copy of a gene during the normal replication process. Throughout the history of life, evolution has molded some of these seemingly superfluous genes into a source of genetic novelty, adaptation and diversity. A new study shows one way that some duplicate genes could have long-ago escaped elimination from the genome, leading to the genetic innovation seen in modern life. Researchers have shown that a process called DNA...

2014-04-08 11:41:02

Researchers have discovered a way of reducing the fertility of malaria-carrying mosquitoes, potentially providing a new tactic to combat the disease. Anopheles gambiae mosquitoes are the main transmitters of malaria, which affects around 200 million people every year. The females mate only once during their lives. They store the sperm from this single mating in an organ called the spermatheca, from which they repeatedly take sperm over the course of their lifetime to fertilize the eggs...

2014-04-08 11:36:36

Melbourne researchers have solved a puzzle as to how an essential blood-making hormone stimulates production of the blood clotting cells known as platelets. Platelets are essential for stopping bleeding and are produced by small fragments breaking off their 'parent' cells, called megakaryocytes. The discovery, made by scientists at the Walter and Eliza Hall Institute, identified how bone marrow cells could become overstimulated and produce too many platelets. In blood diseases such as...

2014-04-01 13:13:29

Scientists have for the first time come closer to understanding how a clone of E. coli, described as the most important of its kind to cause human infections, has spread across the world in a very short time. E. coli clone ST131 is one of the leading causes of urinary tract and blood stream infections and has crossed the globe at a rapid rate. Worryingly, members of this clone are becoming more resistant to antibiotics. As an indication of scale, more than half of all women will suffer a...

2014-04-01 13:02:44

Antibiotics being explored for the treatment of cystic fibrosis and muscular dystrophy have the potential to trigger autoimmune disease The code for every gene includes a message at the end of it that signals the translation machinery to stop. Some diseases, such as cystic fibrosis and Duchenne muscular dystrophy, can result from mutations that insert this stop signal into the middle of an essential gene, causing the resulting protein to be truncated. Some antibiotics cause the cell's...


Latest Proceedings of the National Academy of Sciences Reference Libraries

Proceedings of the National Academy of Sciences
2012-05-29 11:19:42

The Proceedings of the National Academy of Sciences of the United States of America (PNAS) is a peer-reviewed scientific journal established in 1914 as the official journal of the US National Academy of Sciences. The first managing editor of the journal was mathematician Edwin Bidwell Wilson. As of May 2012, the editor-in-chief is Inder M. Verma. PNAS is published weekly in print, and daily online in PNAS Early Edition. The first issue of PNAS was published in 1915, and the journal...

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Word of the Day
snash
  • To talk saucily.
  • Insolent, opprobrious language; impertinent abuse.
This word is Scots in origin and probably imitative.