Stem cells

Health bites

PUBLISHED : Tuesday, 05 February, 2013, 12:00am
UPDATED : Monday, 18 February, 2013, 5:06pm


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Working out how to avoid Alzheimer's

Work out now and continue to reap the benefits later. A new study in the United States has found that having a higher fitness level in midlife appears to be associated with a lower risk of developing Alzheimer's disease and other types of dementia in later years. 

Between 1970 and 2009, researchers at a community health clinic carried out an exercise treadmill test to assess the baseline fitness levels of 19,458 non-elderly, community-dwelling adults who were in generally good health. The researchers reviewed date from Medicare, the US national health insurance programme, for the patients who became eligible to receive benefits between January 1, 1999, and December 31, 2009. They found that patients who were physically fit earlier in life were much less likely to develop dementia than those who were less fit.

Solution to gnawing doubts on research

Many experimental drugs work very well in rodents but fail miserably when tested in people - but this may change in the near future. Scientists at the University of Southern California in Los Angeles have genetically engineered mice that possess an immune response system more like a human's. 

In a study published by the Proceedings of the National Academy of Sciences, the USC researchers "humanised" certain cell molecules in mice to produce a desired response to the cancer drug á-galactosylceramide. "It's the best model we have in the field," said assistant professor Weiming Yuan, principal investigator of the study. "We've basically set a platform to fast-track the identification of immunotherapies that can kill cancer and also make vaccines stronger." He added: "Before, it would have been a guess as to whether the drug would work in people. Now, the chance of success goes from one out of 100 to one out of five."

Making sense of taste loss

With food being one of the joys of life, losing one's sense of taste could be depressing. But a new study published in the journal Stem Cells offers hope for the development of techniques to grow and manipulate new functional taste cells for both clinical and research purposes. Scientists at the Monell Centre in Philadelphia have identified the location and certain genetic characteristics of elusive taste stem cells on the tongue located in clusters called taste buds. Two types of taste cells contain chemical receptors that initiate perception of sweet, bitter, umami, salty, and sour taste qualities. A third type appears to serve as a supporting cell. A remarkable characteristic of these sensory cells is that they regularly regenerate, with an average lifespan of 10 to 16 days.

Where the living is wheezy

Living close to the equator guarantees you warm weather all year round, but it could also put you at a higher risk of developing asthma and allergies, according to new research in the Annals of Allergy, Asthma & Immunology. The culprit: exposure to UV-B rays, which is higher in areas closer to the equator. "This increase in UV-B may be linked to vitamin D, which is thought to modify the immune system. These modifications can lead to an elevated risk of developing allergy and asthma," says lead study author Vicka Oktaria.