11 May, 2015

Household air pollution weakens lung immunity

Household air pollution can cause weaknesses in the immune function of the lung even in healthy people, which can lead to higher rates of pneumonia, a new research has found. 

"Our cell based research has shown that HAP (household air pollution) exposure goes hand in hand with a reduced immune capacity to deal with lung infection. Vulnerable groups such as women and children in low income countries are most likely to be affected," said Jamie Rylance, respiratory specialist at Aintree University Hospital in Britain. 

Three billion people worldwide are exposed to HAP from the fuels they burn to cook, light and heat with at home. Frequently, charcoal, wood and food waste are burned and generate high concentrations of smoke particles. 

This exposure is associated with increased risk of pneumonia, particularly in low and middle income countries where bacterial pneumonia is the biggest cause of infant mortality. This risk is well known, but the reasons are not. 

The new research offers an explanation. 

In the southeast African country Malawi, the research team examined healthy volunteers who had frequent exposure to HAP. Using a telescope test, the team took samples of the immune cells from the lung airways. 

These "alveolar macrophages" are a major defence against infection and clean up the lung airways by ingesting inhaled particles and bacteria. 

Macrophage cells produce toxins which kill the bacteria they have taken up in a process called oxidative burst. 

The study measured the smoke particle content of the macrophage cells. More smoke exposure was associated with a weaker killing response. 

The study was published in the American Journal of Respiratory Cell and Molecular Biology. 

Source: www.timesofindia.com

11.05.2015

Stress disorder linked to faster ageing

People with post-traumatic stress disorder (PTSD) may also be at risk for accelerated ageing or premature senescence, finds a team of researchers including an Indian-origin scientist. 

PTSD is associated with number of psychological maladies including chronic depression, anger, insomnia, eating disorders and substance abuse. 

"This is the first study of its type to link PTSD, a psychological disorder with no established genetic basis, which is caused by external, traumatic stress, with long-term, systemic effects on a basic biological process such as ageing," said Dilip V. Jeste, professor of psychiatry at University of California - San Diego. 

Jeste and colleagues conducted a comprehensive review of published empirical studies relevant to early ageing in PTSD, covering multiple databases going back to the year 2000. 

The team identified 64 relevant studies; 22 were suitable for calculating overall effect sizes for biomarkers and 10 for mortality. 

Seven of 10 studies indicated a mild-to-moderate association of PTSD with earlier mortality, consistent with an early onset or acceleration of ageing in PTSD. 

"These findings do not speak to whether accelerated ageing is specific to PTSD, but they do argue the need to re-conceptualize PTSD as something more than a mental illness," said first author James B. Lohr, professor of psychiatry. 

Early senescence, increased medical morbidity and premature mortality in PTSD have implications in health care beyond simply treating PTSD symptoms. 

"Our findings warrant a deeper look at this phenomenon and a more integrated medical-psychiatric approach to their care," Lohr concluded. 

The study appeared online in the American Journal of Geriatric Psychiatry.

Source: www.timesofindia.com

11.05.2015

You can’t build a reputation on what you’re going to do

Henry Ford