what's the buzz...

Heart tissue from bone stem cells 

Researchers have found that stem cells in cortical, or compact, bone do a better job when it comes to the regeneration of heart tissue than the heart’s own stem cells. 

The findings by senior investigator, Steven R. Houser, at Temple University School of Medicine’s Cardiovascular Research Center (CVRC), have considerable implications for stem cell therapy for the heart. 

Stem cells are youthful by degrees, and cortical bone-derived stem cells (CBSCs) are considered some of the most pluripotent – like human newborns, naive and ready to become anything. But while CBSCs and similarly pluripotent stem cells retain the ability to develop into any cell type needed by the body and sometimes bring their youthful energy to the aid of mature cells – making them especially appealing for therapeutics – they also have the potential to wander off course, possibly landing themselves in unintended tissues. To figure out how CBSCs might behave in the heart in the first place, Houser’s team began by collecting the cells from mouse tibias. The particular mice used had been engineered with green fluorescent protein (GFP), which meant that the CBSCs carried a green marker to allow for their later identification. The cells were then expanded in petri dishes in the laboratory before being injected directly into the hearts of non-GFP mice that had suffered heart attacks. Some mice received cardiac stem cells instead of CBSCs.
 Cataract surgery linked to longer life

People who have had cataract surgery to improve their sight live longer than those who choose not to undergo the procedure, according to a new study.  The research is drawn from data gathered in the Blue Mountains Eye Study, a population-based cohort study of vision and common eye diseases in an older Australian population. 

A total of 354 persons aged 49 years and older and diagnosed with cataract-related vision impairment – some of whom had undergone surgery and others who had not – were assessed between 1992 and 2007. 

Jie Jin Wang, Ph.D., of the Westmead Millennium Institute and one of lead researchers of the study, said that their findings suggested that correcting cataract patients’ visual impairment in their daily practice results in improved outcomes beyond that of the eye and vision, and has important impacts on general health. 

Wang noted one limitation of the study is that participants with cataract-related visual impairment who did not have cataract surgery could have had other health problems that prevented them from undergoing surgery, and that these other health problems could partly explain the poorer survival among non-surgical participants. 
Bats and dolphins evolved echolocation in same way 

Scientists have found that there are certain genetic similarities between bats and dolphins and that the evolution of similar traits in different species, a process known as convergent evolution, is widespread not only at the physical level, but also at the genetic level.  The scientists carried out one of the largest genome-wide surveys of its type to discover the extent to which convergent evolution of a physical feature involves the same genes. 

They compared genomic sequences of 22 mammals, including the genomes of bats and dolphins, which independently evolved echolocation, and found genetic signatures consistent with convergence in nearly 200 different genomic regions concentrated in several “hearing genes”.  The team sifted through millions of letters of genetic code using a computer program developed to calculate the probability of convergent changes occurring by chance, so they could reliably identify 'odd-man-out' genes. 

Comments (+)