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The origin of human bipedalism

While no one has an authoritative answer, anthropologists have long theorized that early humans began walking on two legs as a way to reduce locomotor energy costs.

In the first study to fully examine this theory among humans and adult chimpanzees, published online July 17 in the Proceedings of the National Academy of Sciences, researchers have found that human walking is around 75 percent less costly, in terms of energy and caloric expenditure, than quadrupedal and bipedal walking in chimpanzees.

What determines the speed at which birds fly?

Aerodynamic scaling rules that explain how flight varies according to weight and wing loading have been used to compare general speeds of a wide range of flyers, from the smallest insects to the largest aircraft. In a paper published this week in the open access journal PLoS Biology, Thomas Alerstam, Mikael Rosen, and colleagues from the University of Lund in Sweden analyze the flight speeds of 138 bird species and overturn the general assumption that maximum flight speed of a species is solely determined by such rules.

Nano propellers pump with proper chemistry

The ability to pump liquids at the cellular scale opens up exciting possibilities, such as precisely targeting medicines and regulating flow into and out of cells. But designing this molecular machinery has proven difficult.

Now chemists at the University of Illinois at Chicago have created a theoretical blueprint for assembling a nanoscale propeller with molecule-sized blades.

The work is featured in Research Highlights in the July 12 issue of Nature and was described in the June 28 cover story of Physical Review Letters.

Immune system 'escape hatch' gives cancer cells traction

Scientists at Johns Hopkins and elsewhere say they have mapped out an escape route that cancers use to evade the body’s immune system, allowing the disease to spread unchecked.

In a report published in the July 1 issue of the journal Nature Medicine, the Hopkins team, along with researchers from Florida and Nebraska, describe how myeloid-derived suppressor cells (MDSCs), which normally keep the immune system in check and prevent it from attacking otherwise healthy tissue, can suppress the anti-tumor response to cancer.

A decisive step toward a cure for insulin dependent diabetes

A diagnosis of type I diabetes means a life sentence of medical follow-up. While treatments have become simpler and less restrictive in recent years, they are still a burden, especially for young patients. The latest study published in the journal Nature by Dr. Constantin Polychronakos, Director of the Pediatric Endocrinology Department at the MUHC, in collaboration with Dr. Hakon Hakonarson, Director of the Centre for Applied Genomics of the Children’s Hospital of Philadelphia (CHOP), provides hope that this situation will evolve in the long term toward a cure for this disease.

Pediatricians say advice to obese kids and families falls on deaf ears

Pediatricians who talk to obese patients and their families about losing weight feel their conversation makes little difference in encouraging a lifestyle change, a small Saint Louis University study finds.

“Pediatricians feel as if their efforts are futile,” says Sarah Barlow, M.D., the lead author of the study who also is an associate professor of pediatrics at Saint Louis University School of Medicine and pediatric obesity specialist at SSM Cardinal Glennon Children’s Medical Center.

Patients not complying with dermatologic treatment a universal problem

Patients not complying with their dermatologic treatment is a universal problem that doctors need to address, according to Steven Feldman, M.D., Ph.D., from Wake Forest University School of Medicine in an editorial published in the current issue of Archives of Dermatology. He said non-compliance can explain why some conditions may seem resistant to treatment.

Rates of cutaneous T-cell lymphoma increase over 30 years

The cancer known as cutaneous T-cell lymphoma became substantially more common in the United States between 1973 and 2002, according to a report in the July issue of Archives of Dermatology, one of the JAMA/Archives journals. The rates of the disease vary by race, sex and geographic area.

Cutaneous T-cell lymphoma occurs when certain cells of the lymph system (called T lymphocytes) become cancerous and affect the skin. The term covers several types of lymphoma, according to background information in the article. The nationwide rates of the disease were last documented in 1992.

What Is The Function Of All Those Proteins?

There are hundreds of thousands of proteins for which amino acid sequence data are available, but whose structure and function remain unknown.

Now a research team, led by University of Illinois biochemistry professor John A. Gerlt, has devised a method to use a computational approach to accurately predict a protein’s function from its amino acid sequence. Their “in silico” (computer-aided) predictions were validated in the laboratory by means of enzyme assays and X-ray crystallography.

Ago2 And Hematopoiesis

Argonaute 2 (Ago2) is unique among its family: It is the only one of the four mammalian Argonaute proteins that exhibits endonuclease “slicer” activity (facilitation of miRNA-guided cleavage of target mRNA).

However, as Drs. Donal O’Carroll and Alexander Tarakhovsky (The Rockefeller Institute) report, Ago2’s defining characteristic is surprisingly non-essential for its role in hematopoiesis and miRNA biogenesis.

Suicide Cells

When a cell is seriously stressed, say by a heart attack, stroke or cancer, a protein called Bak just may set it up for suicide, researchers have found.

In a deadly double whammy, Bak helps chop the finger-like filament shape of the cell’s powerhouse, or mitochondrion, into vulnerable little spheres. Another protein Bax then pokes countless holes in those spheres, spilling their pro-death contents into the cell.

Cytokine IL6 As A New Target For Pancreatic Cancer

By bypassing a well-known gene implicated in almost one-third of all cancers and instead focusing on the protein activated by the gene, Dr. Christopher Counter and colleagues at the Duke University Medical Center have identified IL6 as a new target in the battle against Ras-induced cancers.

New use for a cell toxin found to inhibit survival proteins in cancer cells

A chemically-modified version of a mitochondrial toxin long used to control species of invasive fish in lakes has been found to selectively inhibit two "survival proteins” in cancer cells. The research is a first step toward developing a molecularly-targeted drug that could eliminate cellular-level resistance to multiple types of chemotherapy and radiation therapy found in many types of cancers.

Network model predicts risk of death in sickle cell disease

Researchers from Boston University School of Medicine (BUSM) and Boston University School of Public Health (BUSPH) have developed a method to estimate sickle cell disease severity and predict the risk of death in people with this disease. The study appears online in the June issue of the journal Blood.

Small molecules may explain psoriasis

A research team at the Swedish medical university Karolinska Institutet has shown for the time that microRNA, small RNA molecules, may play an important role in the development of inflammatory skin diseases such as psoriasis and atopic eczema. The research team is led by Professor Mona Ståhle, one of Sweden’s most prominent scientists in the field.