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Archive - Apr 2, 2013

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Vitamin P May Be Useful in Treating Damaged Motor Neurons

Biologists from the Ruhr-Universität Bochum (RUB) in Germany have explored how to protect neurons that control movements from dying off. In the journal Molecular and Cellular Neuroscience, the scientists report that the molecule 7,8-dihydroxyflavone, also known as vitamin P, ensures the survival of motor neurons in culture. It sends the survival signal on another path than the molecule brain-derived neurotrophic factor (BDNF), which was previously considered a candidate for the treatment of motor neuron diseases or after spinal cord damage. "The brain-derived neurotrophic factor only had a limited effect when tested on humans, and even had partially negative consequences," says Professor Stefan Wiese from the RUB Work Group for Molecular Cell Biology.. "Therefore we are looking for alternative ways to find new approaches for the treatment of neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS)." ALS is also known as Lou Gehrig’s disease. In previous studies, researchers hypothesized that vitamin P is an analogue of BDNF and thus works in the same way. This theory has been disproved in the current work by the team led by Dr. Teresa Tsai and Professor Stefan Wiese, from the RUB Group for Molecular Cell Biology and the Department of Cell Morphology and Molecular Neurobiology headed by Professor Andreas Faissner. Both substances ensure that isolated motor neurons of the mouse survive in cell culture and grow new processes, but what exactly the molecules trigger at the protein level varies. BDNF activates two signaling pathways, the so-called MAP kinase and PI3K/AKT signal paths. Vitamin P, on the other hand, activates only the PI3K/AKT signal path. However, vitamin P only exerted its positive effects on the motor neurons in a very small concentration range.

New Clues to Formulation of Mysterious Maya Blue Pigment

The recipe and process for preparing Maya Blue, a highly resistant pigment used for centuries in Mesoamerica, were lost. We know that the ingredients are a plant dye, indigo, and a type of clay known as palygorskite, but scientists do not know how they were “cooked” and combined together. Now, a team of chemists from the University of Valencia and the Polythecnic University of Valencia (Spain) have come up with a new hypothesis about how the mysterious pigment was prepared. Palace walls, sculptures, codices, and pieces of pottery produced by the ancient Maya incorporate the enigmatic Maya Blue. This pigment, which was also used by other Mesoamerican cultures, is characterised by its intense blue colour but, above all, by the fact that it is highly resistant to chemical and biological deterioration. Indeed, it was used centuries ago and when it is analyzed now it appears virtually unchangeable. There is no document that verifies how this paint was prepared and so it remains a mystery. Archaeologists and scientists have sought to uncover the mystery in recent years but it seems that researchers cannot come to an agreement. The dominant theory proposes that there is a single type of Maya Blue that was also prepared in a unique way and that a specific type of bond binds the two components: one organic component, indigo, the dye used for denim that is obtained from the Indigofera suffruticosa plant in Mesoamerica, and another inorganic component, palygorskite, a type of clay characterized by its crystal structure full of internal channels. But the work of a team from the University of Valencia (UV) and the Polytechnic University of Valencia (UPV) seems to contradict this “monoist” version.

Embryonic DNA Sampled after IVF for First Time Without Biopsy

Preimplantation genetic diagnosis (PGD) technologies allow identification of genetic disorders in human preimplantation embryos after in vitro fertilization (IVF) and before the embryo is transferred back to the patient. This technique allows couples with a high risk of passing on inherited diseases, to increase their chances of having a healthy baby. Despite the theoretical benefits of PGD, clinical outcomes using these technologies vary, possibly because of the need to remove one or more cells from the embryo using biopsy. In a study published on March 13, 2013 in Reproductive Biomedicine Online, a group of researchers from Italy and the United Kingdom sought to achieve diagnosis of genetic disease in embryonic DNA without the use of a biopsy. By extracting fluid from human embryos at the blastocyst stage they found that it contains DNA from the embryo. Blastocysts are 5- or 6-day-old embryos and are at the last free-living stage that can be studied in the laboratory prior to transfer into the uterus. Blastocysts contain between 50 and 300 cells that surround a fluid-filled cavity called the blastocoel.. The researchers carefully removed fluid from the blastocoel, leaving the cells intact. The sampled blastocysts were subsequently cryopreserved. This study employed real-time PCR to show that genomic DNA was present in about 90% of blastocoele fluid samples harvested. Moreover, the potential for determining embryo sex directly from blastocoele fluid was demonstrated by amplifying the multicopy genes TSPY1 (on the Y chromosome) and TBC1D3 (on chromosome 17). The authors said this opens up the possibility of screening embryos from couples carrying an X-linked disorder to identify male embryos at high risk of disease.