Swine flu virus structure uncovered
A team of scientists from The Scripps Research Institute and other institutions has uncovered the structure of a key protein from the virus that caused last year’s “swine flu.” The structure is that of the influenza virus envelope protein from the H1N1 swine flu virus that triggered the 2009 pandemic and is still circulating in the human population.
Researchers compared the protein with a range of different human flu viruses and found it was similar to earlier viruses of the last century. This is strong evidence that exposure to earlier viruses provided immunity to the current flu strain and helps explain why, in general, older individuals have been less severely affected by the recent flu outbreak.
The findings are published in Science Express, an advance, online publication of selected research papers from the journal Science.
News release at
A healing feat
Researchers at the Salk Institute for Biological Studies and the Center for Regenerative Medicine in Barcelona have identified cells in zebrafish with the ability to heal damaged heart muscle.
These are not stem cells but cardiac muscle cells (cardiomyocytes) whose normal function is to supply the contracting force of the heart.
To identify which zebrafish heart muscle cells possess regenerative properties, the research team engineered cardiomyocytes with a tracer gene that made them glow green.
After removing a portion of fish heart muscle, they awaited regrowth and noted the presence of glowing cells indicating that cardiomyocytes had replaced damaged tissue.
This finding could provide insight into how mammalian hearts might be coaxed into repairing themselves after injury instead of developing scar tissue, which renders damaged heart muscle incapable of contracting.
The study is published in the journal Nature.
News release at
The test commonly used to screen children for chronic liver disease is often incorrectly interpreted in many hospitals throughout the United States. That’s the finding from a study by researchers at the UCSD School of Medicine.
The test measures serum alanine aminotransferease (ALT) — related to an enzyme activity in the liver — to diagnose the presence of disease; however, the appropriate ALT threshold for detecting liver disease in children is unknown. A broad range of ALT test values is found among hospitals, meaning that a child identified with liver disease at one hospital would go undetected in another.
Investigators set out to remedy this by assessing ALT in nearly 1,000 healthy children and found different upper limits of normal for ALT in girls and boys. These new values were also found to be less than half of what is currently used for diagnosis.
In order to determine how useful these new ALT values would be, additional groups of children, with and without liver disease, were tested. Based on the current values used by hospitals, only one-third to one-half of children with chronic liver disease would be detected. The new biologically based values improved the detection rate to 70 percent to 80 percent.
The study appears in the journal Gastroenterology.
Lynne Friedmann is a science writer based in Solana Beach.