Tag Archives: african

Computer models figure out sickle cell crisis

A sickle cell crisis isn’t just about sickle-shaped red blood cells that block capillaries. A second, stickier kind of red blood cell starts the obstruction, making it difficult for sickle cells to flow past.

PROVIDENCE, R.I. [Brown University] — Using powerful computer models, researchers from Brown University have shown for the first time how different types of red blood cells interact to cause sickle cell crisis, a dangerous blockage of blood flow in capillaries that causes searing pain and tissue damage in people with sickle cell disease.

The models showed that the rigid, crescent-shaped red blood cells that are the hallmark of sickle cell disease don’t cause these blockages on their own. Instead, softer, deformable red blood cells known as SS2 cells start the process by sticking to capillary walls. The rigid sickle-shaped cells then stack up behind the SS2s, like traffic behind a car wreck. (more…)

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Jordanna Bailkin studies postwar Britain in new book ‘The Afterlife of Empire’

Jordanna Bailkin is a University of Washington professor of history and author of the new book “The Afterlife of Empire.” She answered a few questions about the book for UW Today.

Q: What is the central concept behind this book?

A: I wanted to understand how Britain and Britons were affected by losing their empire, and how they were changed — often in deeply personal ways — by this process of decolonization. (more…)

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Harmful Protein-Coding Mutations in People arose Largely in the Past 5,000 to 10,000 Years

A study dating the age of more than 1 million single-letter variations in the human DNA code reveals that most of these mutations are of recent origin, evolutionarily speaking. These kinds of mutations change one nucleotide – an A, C, T or G – in the DNA sequence. Over 86 percent of the harmful protein-coding mutations of this type arose in humans just during the past 5,000 to 10,000 years.

Some of the remaining mutations of this nature may have no effect on people, and a few might be beneficial, according to the project researchers. While each specific mutation is rare, the findings suggest that the human population acquired an abundance of these single-nucleotide genetic variants in a relatively short time. (more…)

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UF Biologist Discovers Mammal with Salamander-like Regenerative Abilities

GAINESVILLE, Fla. — A small African mammal with an unusual ability to regrow damaged tissues could inspire new research in regenerative medicine, a University of Florida study finds.

For years biologists have studied salamanders for their ability to regrow lost limbs. But amphibian biology is very different than human biology, so lessons learned in laboratories from salamanders are difficult to translate into medical therapies for humans. New research in the Sept. 27 issue of the journal Nature describes a mammal that can regrow new body tissues following an injury. The African spiny mouse could become a new model for research in regenerative medicine. (more…)

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Face to Face

Research finds infants classify faces by gender, race

Long before babies can talk — even before they can sit up on their own — they are mentally forming categories for objects and animals in a way that, for example, sets apart squares from triangles and cats from dogs, psychologists say.

Now, research conducted by the University of Delaware’s Paul Quinn, professor of psychology, and others indicates that babies as young as 3 months are also classifying faces by race and gender, showing a visual preference for the category they see most often in their daily lives, and that by 9 months they have difficulty recognizing the faces of people from less-familiar races. (more…)

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Human Brain Evolution Tied to Partial Gene Copy That Blocks Original

A brain-development gene found exclusively in humans has an unusual evolutionary history and could contribute to what makes us distinctly human. Equally surprising, this is a partial gene created from an incomplete duplication of its “parent” gene in the prehistoric human genome.

Gene duplication is an important driving force in creating physical changes in living things during evolution, explained the researchers studying the SRGAP2 gene family. Drs. Megan Dennis and Xander Nuttle, in the Howard Hughes Medicine Institute research lab of Dr. Evan Eichler, University of Washington professor of genome sciences, co-authored the report on the findings. (more…)

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