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Archive - Nov 13, 2015

Increased Dietary Potassium May Reduce Risk of Kidney Failure and Heart Disease in Type 2 Diabetes

Diets rich in potassium may help protect the heart and kidney health of patients with type 2 diabetes, according to a study published online on November 12, 2015 in the Clinical Journal of the American Society of Nephrology (CJASN). The article is titled “Urinary Potassium Excretion and Renal and Cardiovascular Complications in Patients with Type 2 Diabetes and Normal Renal Function." Individuals with type 2 diabetes are at increased risk of developing kidney failure and heart disease, which are are common life-threatening complications of diabetes To examine whether higher intake sodium and potassium are associated with these risks, Shin-ichi Araki, M.D., Ph.D., Shiga University of Medical Science, in Japan, and his colleagues studied a group of 623 patients with type 2 diabetes and normal kidney function. Patients were enrolled between 1996 and 2003 and were followed-up until 2013. Higher levels of urinary potassium excretion, which closely correlate with potassium intake amounts, were linked with a slower decline of kidney function and a lower incidence of cardiovascular complications. Sodium levels were not associated with kidney or heart health during follow-up. "For many individuals with diabetes, the most challenging part of a treatment plan is to determine what to eat. The results in our study highlight the importance of a diet high in potassium in diabetes nutrition therapy," said Dr. Araki.

[Press release] [Clinical Journal of the American Society of Nephrology article]

Birds Have Retained “Unique” Ascending Process of Dinosaur Ankle, But Re-Evolved Its Developmental Mechanism

In the 19th century, Darwin’s most vocal scientific advocate was Thomas Henry Huxley, who is also remembered as a pioneer of the hypotheses that birds are living dinosaurs. Huxley noticed several similarities of the skeleton of living birds and extinct dinosaurs, among them, a pointed portion of the anklebone projecting upwards onto the shank bone (also known as the “drumstick”). This “ascending process” is well known to specialists as a unique trait of dinosaurs. However, until the late 20th century, many scientists were doubtful about the dinosaur-bird link. Some pointed out that the ascending process in most birds was a projection of the neighboring heel bone, rather than the anklebone. If so, it would not be comparable, and would not support the dinosaur-bird link. Some argued that, in bird embryos, the ascending process develops from the anklebone in dinosaur-like fashion, while others considered that its development in birds is unique and different from dinosaurs. Nowadays, the dinosaur-bird link is mainstream science, thanks to new methods of data analysis, and a dense series of intermediate fossils (including feathered dinosaurs). However, the disagreements about the composition and embryology of the avian ankle were never clarified fully. Now, a new study, published online on November 13, 2015 in an open-access article in Nature Communications, and authored by Luis Ossa, Ph.D., Jorge Mpodozis, Ph.D., and Alexander Vargas, Ph.D., all from the University of Chile, provides a careful re-examination of ankle development in six different major groups of birds, selected specifically to clarify conditions in their last common ancestor. The study also utilizes new techniques that allow three-dimensional analysis of fluorescent embryonic skeletons, using advanced spin-disc confocal microscopy and software.

Ancient Bees Collected Pollen in Two Different Ways--As Specialists & Generalists; Study of 50-Million-Year-Old Specimens of Bees & Pollen Suggests Specialist-Only Pollen Collection Was Very Rare Phenomenon

Were ancient bees specialists, devoting their pollen-collecting attentions to very specific plant partners? Or were they generalists, buzzing around to collect pollen from a variety of flowers in their midst? Researchers who have studied an ancient lineage of bees now say, in an open-access article published online on November 12, 2015 in the Cell Press journal Current Biology, that the answer to both questions is “yes.” Bees living some 50 million years ago simultaneously relied on both strategies in foraging for pollen. The new Current Biology article is titled “Specialized and Generalized Pollen-Collection Strategies in an Ancient Bee Lineage.” "Because the fossil record of bees extends to the Late Cretaceous, and an early bee-like ancestor is known from 100 million-year-old amber, it could very well be that this dual foraging behavior may be as old as bees themselves," says Conrad Labandeira, Ph.D., of the Smithsonian Institution in Washington, D.C.. and a Fellow at the Paleontological Society. "If this is the case, then the controversy as to whether the earliest bees were generalist or specialist pollen collectors may be moot: the earliest bees during the mid-Cretaceous may have been simultaneously generalists and specialists!” The researchers, led by Heisenberg Fellow of the German Science Foundation Torsten Wappler, Ph.D., from the University of Bonn in Germany, identified pollen found on the bodies of eleven individuals from six bee species of the tribe Electrapini collected from two sites in Germany. The bee specimens were 44 million to 48 million years old, with pollen well preserved across their bodies. The researchers found pollen from a wide variety of nectar-producing flower types all across the bees' bodies--except, that is, on their legs.