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Ethnicity could vary immunity to H7N9 

Owing to genetic differences, people could vary in their ability to mount a cell-mediated immune response against the H7N9 influenza virus that emerged in February last year, a new study has suggested.

Animal and human studies suggest that, in the absence of protective antibodies against a new influenza strain, cross-reactive CD8+ T lymphocytes (CTLs) generated previously against other influenza strains can diminish disease severity, and may therefore provide some protection against the H7N9 virus.

Peter Doherty and colleagues investigated the capacity of pre-existing influenza-specific CTLs to respond to the H7N9 virus in individuals not previously exposed to the virus.

The researchers found that 28 per cent of the H7N9 peptides with the capacity to elicit CTL responses are also found in other influenza A viruses that caused past human pandemics or epidemics. They then estimated that the human leukocyte antigens (HLAs) capable of presenting immunogenic influenza peptides to CTLs are present in approximately 16-57 per cent of the population, and vary in prevalence depending on ethnicity.

Analyses of blood cells from 52 healthy human donors incubated with the peptides in vitro revealed that some HLA alleles elicit robust CTL responses against any human influenza A virus, including H7N9, whereas other alleles, such as those that tend to be prevalent in the indigenous people of Alaska and Australia, displayed limited CTL responses.

How to maintain long-term weight loss

Researchers have published new studies that show that long-term weight loss maintenance is possible if people stick to key health behaviors.

J. Graham Thomas, Ph.D., is the lead author on a 10-year observational study of self-reported weight loss and behavior change in nearly 3,000 participants.

The participants had lost at least 30 pounds and had kept if off for at least one year when they were enrolled in the National Weight Control Registry (NWCR).

The participants were then followed for 10 years. Thomas explains that the goal of the study was to determine how well they kept the weight off and to identify predictors of successful weight loss maintenance.

Thomas said that on average, participants maintained the majority of their weight loss over this extended follow-up period, and better success was related to continued performance of physical activity, self-weighing, low-fat diets, and avoiding overeating.
Mother’s touch vital for premature infants

Scientists have claimed that the benefits that premature infants gain from skin-to-skin contact with their mothers is measurable even 10 years after birth.

Specifically, the researchers compared standard incubator care to a novel intervention called “Kangaroo Care” (KC), which uses the mother’s body heat to keep their babies warm.

They asked 73 mothers to provide skin-to-skin contact (KC) to their premature infants in the neonatal unit for one hour daily for 14 consecutive days. For comparison, the researchers also assessed 73 premature infants who received standard incubator care.

Children were then followed seven times across the first ten years of life.

They found that during the first half-year of life, mothers in the KC group were more sensitive and expressed more maternal behavior toward their infants. Children in the KC group showed better cognitive skills and executive abilities in repeated testing from six months to ten years.

At ten years of age, children who received maternal contact as infants showed more organized seep, better neuroendocrine response to stress, more mature functioning of the autonomic nervous system, and better cognitive control.

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