Nerdy Science Blog

French and Australian scientists develop a new way of delivering stem cells to regenerate bone.  According to Dr Frank Caruso of the Centre for Nanoscience and Nanotechnology at the University of Melbourne, the new injectable format made of synthetic polymers enclosing growth factor and stem cells can be injected to any part of the bone to mend broken and diseased bones and joints, and only single injection is required.  The sizes of capsules range from about 100 nanometres to ten of microns.  Stem cell capsule may be used for treatment in 5 to 10 years time if all things go well.  One of the problems need to be solved now is the rate of releasing growth factors as it determines the number of injections needed.  Effective stem cell transplantation for bones and joints regrowth is critical as bone cells do not heal themselves very well sometimes.  The development of stem cell delivery in capsule form has been published in the Proceedings of the National Academy of Sciences.

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When did human start eating fish?  Why did human eat fish?  As a creature being on the land, it is unlikely for early human to think fish as a source of food.

An international team of research conducted a chemical analysis of protein collagen of a 40,000-year-old bone found at Tianyuan Cave near Beijing.  They examined the ratios of isotopes of nitrogen and sulfur, and determined that the bone owner was a regular fish consumer.  This study became direct evidence that the earliest modern human who ate fish was back in 40,000 years ago.

This regular fish consumption evidence was before the effective making of fishing equipment.  It is believed that the consumption of aquatic resources may be a reflection of pressure from expanding population when modern human emerged across Eurasia.

The study is published in Proceedings of the National Academy of Sciences.

40 religious and non-religious people were asked to read phrase like “I believe God is with me throughout the day and watches over me”, “God is angry at human behaviour”, “There is no higher purpose”, etc. regardless they agreed or disagreed with the content they were reading.  The team at National Institutes of Health, Bethesda, Maryland, then scan their brains with functional magnetic resonance imaging (fMRI).  From the brain scan, the team found that human brain responds to God as just another person.  There is no difference between the human brain subjects when God is mentioned regardless they are religious or non-religious.  The same part in the brain that is being activated when God is mentioned associated with deciphering the emotions and intentions of others.  The team suggested that religion may be a product of human evolution as human brain evolved, human became capable of handling complex social interactions, and religion is a social behaviour.

This study does not prove the existence of God.  It just tells how God works in our brain. It just tells how god-belief or belief in god(s) works in our brain.  The study will be published in the next issue of Proceedings of the National Academy of Sciences, and the authors are Dimitrios Kapogiannis, Aron K. Barbey, Michael Su, Giovanna Zamboni, Frank Krueger, and Jordan Grafman.

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Whenever I read the news about fruit flies, I can’t help myself repeating a sentence over my mind and in this blog, “Time flies like arrow, fruit flies like banana!”

This time fruit flies may be able to enjoy more bananas in their life.  Researchers from Brown University, University of Chicago, and University of Connecticut Health Center had identified the cellular mechanism of aging gene in fruit flies.  The study was based on the discovery made by Stephen Helfand, a professor in biology, molecular biology, cell biology and biochemistry at Brown University, which mutation of Indy (I’m Not Dead Yet) gene could prolong the life span of fruit flies.  The researchers examined the mutated fruit flies with normal ones at molecular level.  Genes required to produce energy in normal cell life were expressed at lower level in the mutated ones.  This created less free radical which contributed to the aging process.  However the overall energy generated by the mutated fruit flies was the same and the mutated fruit flies lived longer without any side effect.

Scientists suggested this discovery could be used in anti-aging treatment.  The paper was published online on this Wednesday’s Proceedings of the National Academy of Sciences (PNAS).  Other authors are Nicola Neretti, Pei-Yu Wang, Alexander S. Brodsky, Hieu H. Nyguyen, Kevin P. White, and Blanka Rogina.

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A common gene variant links to high blood pressure a.k.a. hypertension has been identified by researchers from the University of Maryland School of Medicine.

Scientists believe that there are multiple genes involved in hypertension.  By using a new technique called genome-wide association study, the first hypertension susceptibility gene, STK39 gene, has been uncovered.  The DNA of 542 members of the Old Order Amish community in Lancaster County, Pa, were analyzed to examine the connection between STK39 gene and blood pressure.  The STK39 gene is located on chromosome 2.  Chromosome 2 is a gene that produce proteins involve in kidney regulation for salt processing, which is essential in controlling blood pressure.  It is found that 20% of the Caucasians in the United States and Europe possess the gene variant.  Senior author Yen-Pei Christy Chang envisioned that the finding can lead to the development of personalized medicine.

The ideal systolic and diastolic blood pressure should be less than 120/80.  Common high blood pressure a.k.a. essential hypertension can be caused by environment and lifestyle factors, such as diet, exercise, and stress level.  It can cause cardiovascular disease, stoke, or kidney failure.

The study is published online on Dec 29th, 2008 in the Proceedings of the National Academy of Sciences (PNAS), titled ‘Whole-genome association study identifies STK39 as a novel hypertension susceptibility gene’.

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Researchers from Oregon State University, Cornell University and the University of North Carolina published their work in Proceedings of the National Academy of Sciences showing the effect of herbivores and omnivores on the prevalence of barley and cereal yellow dwarf viruses.  It is found that grazers such as deer, rabbits and feral pigs actually help to spread plant disease, which is contrary with findings that suggested grazers actually contain or reduce disease.  Elizabeth Borer, an assistant professor of zoology at OSU explained their study is about the interaction of plant pathogens with the complexity of natural ecosystems.  Any small change in the elements of ecosystems can cause butterfly effects with seemingly unrelated diseases, and these changes can be caused by climate change, species population, human manipulation, etc.  One obvious example is that the increase of white-footed mice population is correlated to the increase of Lyme disease risk in humans.  Although the grazers increase the amount of annual grasses, these grasses are preferred by the aphids which transmitted the viral plant disease.

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Scientists found that homosexual men have feminized brain.  They share similar brain as straight women.  The study, led by Dr. Ivanka Savid of the Karolinska Institute in Stockholm, was published in Proceedings of the National Academy of Sciences (PNAS).  This could perhaps explain why homosexual men talk and act like women.  However homosexual women did not share similar brain with heterosexual men.

So gay men are just women soul trapped in men body?

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