Washington, September 19 (ANI): Researchers at the Emory Vaccine Center have shown that HIV relies upon a number of strategies rather than use any preferred escape route to escape immune system pressure.
The human immune system has the ability to temporarily overpower HIV in early infection.
Studies conducted in the recent past have shown that most newly infected patients develop neutralizing antibodies. These are blood proteins that glob onto the virus and would allow patients to defend themselves – if they were facing only one target.
However, the problem occurs when HIV mutates, and disguises itself enough to get away from the antibodies. The virus eventually wears down the immune system into exhaustion.
The Emory team’s findings attain significance as they suggest that even if any scientist succeeds in identifying a vaccine component that can stimulate neutralizing antibodies, HIV’s capacity for rapid mutation could still be a confounding factor.
Dr. Cynthia Derdeyn, associate professor of pathology at Emory University School of Medicine, Emory Vaccine Center and Yerkes National Primate Research Center, says that a single type of neutralizing antibody may not be enough to contain HIV.
“These neutralizing antibodies work really well – they hit the virus fast and hard. But so far, every time we look, the virus escapes,” she says.
During the study, the researchers took blood samples from the participants a few weeks after infection occurred, and then later as two participants’ immune responses continued.
They isolated individual viruses over the first two years of HIV infection, and tested how well the patients’ own antibodies could neutralize them.
“In one patient where we had very early samples, there was evidence that neutralizing antibody came up within weeks, and that’s earlier than what was previously thought,” Derdeyn says.
In both patients, some viruses mutated part of their outer proteins so that after the mutation, an enzyme would be likely to attach a sugar molecule to it.
Though the sugar molecule interferes with antibody attack, this tactic, known as the “glycan shield”, was not observed in all cases.
Other viruses mutated the part of the outer protein that the neutralizing antibodies stick to directly. In both patients, many changes in the virus’ genetic code were necessary for escape.
“We need to understand early events in the immune response if we are going to figure out what a potential vaccine should have in it. What we can show is that even in one patient, several escape strategies are going on,” Derdeyn says.
According to her, that means that in order to be immune to HIV infection, someone may need to have several types of neutralizing antibodies ready to go.
Seeing how the virus mutates will allow researchers to choose the best parts to put in a vaccine, she says.
The results are online and scheduled for publication in the September issue of the journal Public Library of Science Pathogens.(ANI)
Spanking found to have negative effects on low-income toddlers
Washington, September 16 (ANI): Spanking negatively affects the behaviour of toddlers in low-income families, according to a new study.
Published in the journal Child Development, the longitudinal study looked at how low-income parents discipline their young children.
It showed that spanking 1-year-olds leads to more aggressive behaviours and less sophisticated cognitive development in the next two years.
Verbal punishment, however, was not found to be associated with such effects, especially when it was accompanied by emotional support from mothers.
Besides, 1-year-olds’ fussiness predicted spanking and verbal punishment at ages 1, 2, and 3.
The study explored whether mothers’ behaviours lead to problematic behaviour in children, whether children’s challenging behaviours elicit harsher discipline, or both.
It looked at more than 2,500 exclusively low-income White, African American, and Mexican-American mothers and their young children, interviewing and observing them at home when the children were 1, 2, and 3 years old.
All participants’ family incomes were at or below the federal poverty level.
Using their own interpretations of spanking, mothers reported how often anyone in the home had spanked their children in the past week.
The study also looked at how often mothers verbally punished-scolded, yelled, or made negative comments-their children.
It showed that African American children were spanked and verbally punished significantly more than the other children in the study.
The authors speculated that that might be due to cultural factors, such as belief in the importance of children’s respect for elders and in the value of physical discipline to instil that respect.
Moreover, some African American mothers said that in preparing their children for a harsh, physically dangerous, and racially discriminating world, there was little room for error in their childrearing.
The study also shed light on information about the effects of such types of discipline.
“Our findings clearly indicate that spanking affects children’s development,” said Lisa J. Berlin, research scientist at the Center for Child and Family Policy at Duke University and the study’s lead author.
Specifically, children who were spanked more often at 1 behaved more aggressively when they were 2, and had lower scores on tests measuring thinking skills when they were 3.
Similar findings were made even after taking into consideration such family characteristics as mothers’ race and ethnicity, age, and education; family income and structure; and the children’s gender.
The study also found that children who were more aggressive at age 2, and had lower cognitive development scores at ages 1 and 2, were not spanked more at ages 2 and 3.
“So the mothers’ behaviours look more influential than the children’s,” said Berlin.
Unlike spanking, however, verbal punishment alone didn’t affect either children’s aggression or their cognitive development.
Interestingly, when verbal punishment was accompanied by emotional support from moms, the children did better on the tests of cognitive ability. (ANI)