Polarity in Biological News

Weizmann Institute scientists show extra copies of a gene carry extra risk

... study shows that it works by helping to determine polarity in the cell how the various organelles are ... to neighboring cells. Neurons alter their polarity several times during development, especially when ... they discovered a range of subtle changes in cell polarity and movement: Nuclei within the proliferating ...

How an enzyme tells stem cells which way to divide

... adding that the mechanism likely is similar in many other types of cells, not just stem cells. "It's a basic-research question. How does this polarity occur? In order to develop stem cell-specific therapeutics based on a rational methodology you have to understand the mechanism," he said. If ...

Evidence of the 'Lost World' -- did dinosaurs survive the end Cretaceous extinctions?

... The first step must be to demonstrate that the rocks containing the bones are younger than the extinction event. Fassett has analysed the magnetic polarity of the rocks, and the pollen grains they contain, different approaches to finding the age of rocks which, he concludes "independently indicate that ...

Hypertension and cholesterol medications present in water released into the St. Lawrence River

... release locations of wastewaters treated by the treatment stations are the main source of drug dispersion into the environment. Because of their high polarity and their acid-base character, some of the pharmaceutical compounds studied have the potential to be transported and dispersed widely in the aquatic ...

January-February GSA Bulletin media highlights

... Peppe et al., Department of Geology and Geophysics, Yale University, New Haven, Connecticut 06511, USA. Pages 65-79. To determine the geomagnetic polarity stratigraphy and the duration and age of the Ludlow Member of the Fort Union Formation (Lower Paleocene), Peppe et al. constructed a 325 meter ...

Rare genetic disorder gives clues to autism, epilepsy, mental retardation

... from other neurons). This specification of axons and dendrites, known as polarity, is crucial for proper information flow. "We think if initial polarity is not formed properly, the result will be abnormal connectivity in the brain," says Sahin, who also directs the clinical Multi-Disciplinary Tuberous ...

Simulations help explain fast water transport in nanotubes

... hydrogen atoms and one oxygen atom. Although its net charge is zero, the molecule has a positive side (hydrogen) and a negative side (oxygen). This polarity causes the molecule to orient in a particular direction when in the presence of an electric field. Creating and maintaining that orientation, ...

Synthetic molecules emulate enzyme behavior for the first time

... image forms." Despite decades of research, scientists aren't sure exactly how this kind of propagation works. It may have something to do with the polarity of different parts of the molecule, or the chemical environment around the edges of the molecule. But Parquette says the new study demonstrates ...

Simple model cell is key to understanding cell complexity

... of lipid molecules. Some of these lipid molecules contained tiny pieces of PEG, which interacted with the PEG in the cytoplasm, thus generating polarity in the model cell. "Our work demonstrated the interrelationship of the cytoplasm and the cell membrane," said Keating. The team's next step is to ...

Salk scientists identify key nerve navigation pathway

... mutants. As a result, cells lose their polarity. They literally do not know the front end from the back end, according to Pfaff. This sense of polarity is a universal feature common to all growing neurons. Therefore, Phr1 is likely to play a role in most growing neurons to ensure their structure is ...

November GEOLOGY and GSA TODAY Media Highlights

... eccentricity forcing through the Upper Triassic of southwest England and its correlation with the Newark Basin astronomically calibrated geomagnetic polarity time scale from North America David B. Kemp and Angela L. Coe, Neftex Petroleum Consultants Ltd, 115BD Milton Park, Abingdon, Oxfordshire OX14 4SA, ...

Salk scientists get to the root of plant cell fate

... the finding that a co-repressor controls polarity in plants was surprising, says Long. "We thought ... difference between plants and animals in terms of polarity development is how much more tolerant plants are ... divisions are very important to development of polarity and if something goes awry with co-repressors, ...

FSU biologists uncover mechanisms that shape cells for better or worse

... genetic and molecular mechanism that causes cell polarity -- the asymmetric shape or composition critical ... that triggers the development of cell polarity in Drosophila oocytes (unfertilized fruit fly ... could foster a better overall understanding of polarity and how it develops -- and why it doesn't, ...

New insights into neural tube defects

... in vertebrates. During cell division the polarity of a cell is lost. Therefore, the newly formed ... in Nature is the first to demonstrate that the polarity is restored to the daughter cells after rather ... After cell division, proteins that direct the polarity of the cell distribute asymmetrically. This ...

Alleged 40,000-year-old human footprints in Mexico much, much older than thought

... that the rock grains in the volcanic ash had polarity opposite to the Earth's polarity today. Since the last magnetic pole reversal was ... at least that age. Because the Earth's magnetic polarity changes, on average, every 250,000 years, the ...

Technique monitors thousands of molecules simultaneously

... happened at electrodes that were not being used. Reversing the polarity of things "The chip is an ongoing battle between active reagent and ... at specific electrodes. "What electrochemistry does best is to reverse the polarity of things," Moeller said. "It takes things that are electron-poor and ...

Orientation and the egg

... The establishment of first polarity in the developing mammalian embryo is one of the most contentious topics ... researchers showed compelling evidence for the absence of predetermined polarity in the mouse egg. Their findings are in contrast to those who feel that ...

UC Davis researchers use heated nanoprobes to destroy breast cancer cells in mice

... later, the team applied an alternating magnetic field to the tumor region, causing the magnetic nanospheres latched onto the tumor cells to change polarity thousands of times per second, instantaneously generating heat. As soon as the AMF stopped, the bioprobes cooled down. Mice in the study ...

Sticky surfaces turn slippery with the flip of a molecular light switch

... ability to control liquid flow in a chip's ultra-tiny channels. And in sensors designed to detect biological agents, the ability to control the polarity of the membrane could help reduce the attachment of unwanted proteins, providing more accurate readings, according to Belfort. ...

How the neuron sprouts its branches

... or "polarity," of the Golgi -- thus causing them to move into all the dendrites -- without disrupting their function. They found that disrupting the polarity caused all the dendrites to grow at the same rate. Further studies, said Ehlers, will explore how Golgi outposts arise, how they arrive at ...

UCLA cancer researchers shake loose hidden biomarker

... location on the cell could have ramifications for treating the sickest patients, those in whom the cancer has spread. "The ability to reverse the polarity of PSMA from apical to the basolateral could have significant implications for the PSMA as a therapeutic target," the study states. Pairing ...