Scientific discoveries this week: 4/8/13

London, England
By growing and analyzing stem cells from patients’ blood, scientists were able to shed light on a common bleeding disorder. They discovered the cause of the disease in individual patients that can enable doctors to prescribe more effective treatments according to the defects identified in the patients’ cells.
Researchers at the National Heart and Lung Institute, at the Imperial College London focused on von Willebrand disease (vWD) which is estimated to affect 1 in 100 people and can cause excessive possibly life-threatening bleeding. vWD is caused by a deficiency of a blood component involved in making blood clot. The blood component is produced by endothelial cells which line the inside of every blood vessel in the human body. They are difficult to study because taking biopsies from patients is invasive and unpleasant. The researchers took routine blood samples from eight patients with vWD, extracted endothelial progenitor cells, and grew them in the lab to yield large numbers of endothelial cells. By testing these cells they could analyze each patient’s disease. The results enabled them to find new types of defect which may enable them to recommend improved treatments. They are looking to apply these findings to reduce severe bleeding in these patients. The cells could be an invaluable resource for testing new drugs for vWD and other diseases. Endothelial cells derived from blood could also be isolated and reinjected into someone recovering from a heart attack. This would help grow blood vessels and repair the injured heart tissue. It would also avoid the immune system trying to destroy the foreign organ.

California Institute of Technology
NASA’s Kepler space telescope observed the effects of a dead star bending the light of its companion red star. The researchers from the California Institute of Technology used measurements of the star’s ultraviolet activity, which are among the first detections of this result, predicted by Einstein’s theory of general relativity. The dead star is a white dwarf, a burnt-out core of a star like our sun. The white dwarf is physically smaller than the red dwarf but more massive. According to the researchers, the white dwarf is about the size of Earth but the mass of the sun. The team used ultraviolet measurements of the star KOI-256 using the Galaxy Evolution Explorer (GALEX), a NASA space telescope operated by Caltech. The observations and analysis indicate that the red dwarf orbits the white dwarf in 1.4 days. The orbital period is so short that the stars were once in a “common-envelope” where the red dwarf orbited within the outer layers of the star that formed the white dwarf. Furthermore, according to the researchers, in a few billion years, the intense gravity of the white dwarf will strip material off the red dwarf, forming a hot accretion disk of material around the white dwarf.

University of Lincoln, UK
Scientists from the University of Lincoln in the United Kingdom are studying the role of a hearing organ in the South American bushcricket’s ear. They aim to understand how the insects pick up on ultrasonic frequencies in their natural environment. The insects communicate using high pitched calls in nature at about 130 to 150 kHz, which are not detected by humans. Males produce sound by rubbing their wings to attract distant females. The fluid in the katydid cochlea, also named the auditory vesicle, is the key element in the hearing process. The researchers want to investigate why this is the case and the first step is testing the cochlea sensitivity in the insect’s natural environment. In mammals, hearing relies on three main parts, an eardrum collecting sound, a middle ear impedance converter, and a cochlear frequency analyzer. According to the researchers, the bushcricket’s ear performs these steps in the hearing process, which was previously unknown in insects. The high frequency wavelength of the sound is not suited for long-range attraction as it suffers excess attenuation in rainforest environments. The insect’s ear must have therefore evolved sufficient sensitivity at those high frequencies. The bushcricket’s ears are extremely sensitive and have a size and sensitivity advantage over equally responsive microphones. The research can advance other research into the design and construction of ultrasensitive microphones with unusual broad frequency responses.