A new analysis of the remains of a Tyrannosaurus rex (T. rex) that roamed Earth 68 million years ago has confirmed traces of protein from blood and bone, tendons, or cartilage. The findings, scheduled for publication in the Sept. 4 issue of ACS' monthly Journal of Proteome Research, is the latest addition to an ongoing controversy over which biochemical remnants can be detected in the dino.
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A bizarre New Zealand bat that is as much at home walking four-legged on the ground as winging through the air had an Australian ancestor 20 million years ago with the same rare ability, a new study has found.
The discovery overturns a long-held held view that the agile walking and climbing skills of the lesser short-tailed bat - Mystacina tuberculata – evolved in the absence of any ground-dwelling mammal competitors or predators, says an international team of researchers led by Dr Suzanne Hand, a bat expert at the University of New South Wales, Sydney.
A research article to be published on July 21, 2009 in the World Journal of Gastroenterology addresses this question. This research led by Professor Kim and his colleagues in Pusan National University, South Korea. They evaluated the EUS features of gastric GISTs in comparison with gastric leiomyomas, and tried to determine the EUS features that could predict the malignant potential of gastric GISTs according to the histological risk classification.
Hepatitis B virus (HBV) infection is a dynamic process with variable biochemical, virological and histological profiles at different stages of the infection, depending on host and viral factors. Furthermore, this profile may change at a variable pace over time. The correlation between detection of T-cell response and HBV load in chronic HBV infection remains unknown. In each of the clinical stages of chronic HBV infection, whether the composition of T-cell subpopulations is different and relates to viral load.
A major clinical challenge is to find the best method to evaluate and to manage the increasing numbers of patients with chronic liver disease. Liver biopsy, due to its risks and limitations, is no longer considered mandatory as the first-line indicator of liver injury, and several markers have been developed as non-invasive alternatives.
Helicobacter pylori, nonsteroidal anti-inflammatory drug use and smoking are the most important risk factors for peptic ulcer. Alcohol intake may also play a role in the development of gastric ulcers. Psychological stress may also have an impact on the onset and course of ulcer disease. However, very little is known as to whether childhood adversities involving financial problems, conflicts in the family, problems with alcohol, and matters of personal security are associated with peptic ulcer.
Mammals and many species of birds and fish are among evolution's "winners," while crocodiles, alligators and a reptile cousin of snakes known as the tuatara are among the losers, according to new research by UCLA scientists and colleagues.
"Our results indicate that mammals are special," said Michael Alfaro, a UCLA assistant professor of ecology and evolutionary biology and lead author of the research.
Stem cell research promises remedies to many devastating diseases that are currently incurable, ranging from diabetes and Parkinson's disease to paralysis. Totipotent embryonic stem cells have great potential for generating a wide range of different human cells that can be used to restore malfunctioning or damaged cells and tissues in patients. Recent studies have shown that pluripotent stem cells derived from adult bone marrow, the umbilical cord and the placenta could also be induced to differentiate into a variety of different tissues.
Hungry, sexual organisms replaced well-fed, clonal organisms in the Caribbean Sea as the Isthmus of Panama arose, separating the Caribbean from the Pacific, report researchers from the Smithsonian Tropical Research Institute and Scripps Institution of Oceanography. The fossil record shows that if a species could shift from clonal to sexual reproduction it survived. Otherwise it was destined for extinction, millions of years later.
Genetic evidence is revealing that human populations began to expand in size in Africa during the Late Stone Age approximately 40,000 years ago. A research team led by Michael F. Hammer (Arizona Research Laboratory's Division of Biotechnology at the University of Arizona) found that sub-Saharan populations increased in size well before the development of agriculture. This research supports the hypothesis that population growth played a significant role in the evolution of human cultures in the Late Pleistocene.
CHICAGO, IL – In the Late Paleozoic (260 million years ago), long before dinosaurs dominated the Earth, ancient precursors to mammals took to the trees to feed on leaves and live high above predators that prowled the land, Jörg Fröbisch, PhD, a Field Museum paleontologist has concluded. Elongated fingers, an opposable "thumb," and a grasping tail of Suminia getmanovi demonstrate that this small plant-eating synapsid is the earliest known tree-climbing vertebrate
Smokeless tobacco products, as used in Europe and North America, do not appear to increase cancer risk. A large meta-analysis, published in the open access journal BMC Medicine, has shown that snuff as used in Scandinavia has no discernible effect on the risk of various cancers. Products used in the past in the USA may have increased the risk, but any effect that exists now seems likely to be quite small.
The first ever genetic linkage map for a non-avian member of the Class Reptilia has been developed. Researchers writing in the open access journal BMC Genomics have constructed a first-generation genetic linkage map for the saltwater crocodile Crocodylus porosus.
A higher density of blood vessels and other unique physiological features in the flight muscles of bar-headed geese allow them to do what even the most elite of human athletes struggle to accomplish – assert energy at high altitudes, according to a new UBC study.
Named for the dark stripes on the backs of their heads, bar-headed geese are native to South and Central Asia. Often bred in captivity as domestic garden birds, they migrate annually in the wild between India and the high altitude plateaus in China and Mongolia, flying over the world's highest mountains on their way.
Walter and Eliza Hall Institute scientists have created a weakened strain of the malaria parasite that will be used as a live vaccine against the disease.