The US has warned Pakistani leaders of dangerous consequences if there is another terror attack on India that originates from Pakistan, a former top adviser to President Barack Obama has said, asking Islamabad to give up the policy of supporting extremist elements.
Washington, March 19 (ANI): Scientists have discovered a key cellular mechanism that guides embryonic heart tissue formation-a process which, if disrupted, can lead to a number of common congenital heart defects.
Heart tissue forms in two distinct phases known as the First Heart Field, which includes the left ventricle and portions of both atrial chambers, and the Second Heart Field (SHF), which consists of the right ventricle and outflow tract. In humans, the process occurs within the fourth week of development.
Using animal models, researchers at the Keck School of Medicine of the University of Southern California (USC) found that retinoic acid (RA), a derivative of vitamin A, regulates the SHF tissue formation and the septation, or division, of the outflow tract into the ascending aorta and the pulmonary artery.
"This study provides us with a much deeper understanding of the biology of second heart field development," said principal investigator Henry Sucov, associate professor of Cell and Neurobiology at the Keck School of Medicine and a researcher at the Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research at USC.
"We now know that vitamin A is a critical regulator of this process, and too much or too little RA can lead to common congenital defects," Sucov added.
The study appears in the March 16 issue of the journal Developmental Cell. (ANI)
Today : Friday - Feb 10, 2012, 11:48am (GMT+5.5)
