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Neurotoxic organophosphorus compounds (OPs), which are used as pesticides and chemical warfare agents lead to more than 700,000 intoxications worldwide every year. The main target of OPs is the inhibition of acetylcholinesterase (AChE), an enzyme necessary for the control of the neurotransmitter acetylcholine (ACh). The control of ACh function is performed by its hydrolysis with AChE, a process that can be completely interrupted by inhibition of the enzyme by phosphylation with OPs. Compounds used for reactivation of the phosphylated AChE are cationic oximes, which usually possess low membrane and hematoencephalic barrier permeation. Neutral oximes possess a better capacity for hematoencephalic barrier permeation.NMR spectroscopy is a very confident method for monitoring the inhibition and reactivation of enzymes, different from the Ellman test, which is the common method for evaluation of inhibition and reactivation of AChE. In this work 1H NMR was used to test the effect of neutral oximes on inhibition of AChE and reactivation of AChE inhibited with ethyl-paraoxon. The results confirmed that NMR is a very efficient method for monitoring the action of AChE, showing that neutral oximes, which display a significant AChE inhibition activity, are potential drugs for Alzheimer disease. The NMR method showed that a neutral oxime, previously indicated by the Ellman test as better in vitro reactivator of AChE inhibited with paraoxon than pralidoxime (2-PAM), was much less efficient than 2-PAM, confirming that NMR is a better method than the Ellman test.  相似文献   
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Endothelial progenitor cells (EPC) participate in revascularization and angiogenesis. EPC can be cultured in vitro from mononuclear cells of peripheral blood, umbilical cord blood or bone marrow; they also can be transdifferentiated from mesenchymal stem cells (MSC). We isolated EPCs from Wharton's jelly (WJ) using two methods. The first method was by obtaining MSC from WJ and characterizing them by flow cytometry and their adipogenic and osteogenic differentiation, then applying endothelial growth differentiating media. The second method was by direct culture of cells derived from WJ into endothelial differentiating media. EPCs were characterized by morphology, Dil-LDL uptake/UEA-1 immunostaining and testing the expression of endothelial markers by flow cytometry and RT-PCR. We found that MSC derived from WJ differentiated into endothelial-like cells using simple culture conditions with endothelium induction agents in the medium.  相似文献   
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A new fossil brachypterous psocid tax on belonging to the family Trogiidae is characterized, illustrated and described from the early Eocene Fushun amber. Paralepinotus fushunensis nov. gen., nov. sp., shares several characters with the genus Lepinotus von Heyden, 1850, but differs from it mainly by the presence of tibial spurs other than apical ones and the absence of a forked sensillum on the last maxillary palp. This fossil taxon is also characterized by relatively developed elytriform forewing but still not reaching the tip of the abdomen. A checklist of all known Trogiidae is provided.  相似文献   
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Previous genetic studies have demonstrated that natal homing shapes the stock structure of marine turtle nesting populations. However, widespread sharing of common haplotypes based on short segments of the mitochondrial control region often limits resolution of the demographic connectivity of populations. Recent studies employing longer control region sequences to resolve haplotype sharing have focused on regional assessments of genetic structure and phylogeography. Here we synthesize available control region sequences for loggerhead turtles from the Mediterranean Sea, Atlantic, and western Indian Ocean basins. These data represent six of the nine globally significant regional management units (RMUs) for the species and include novel sequence data from Brazil, Cape Verde, South Africa and Oman. Genetic tests of differentiation among 42 rookeries represented by short sequences (380 bp haplotypes from 3,486 samples) and 40 rookeries represented by long sequences (∼800 bp haplotypes from 3,434 samples) supported the distinction of the six RMUs analyzed as well as recognition of at least 18 demographically independent management units (MUs) with respect to female natal homing. A total of 59 haplotypes were resolved. These haplotypes belonged to two highly divergent global lineages, with haplogroup I represented primarily by CC-A1, CC-A4, and CC-A11 variants and haplogroup II represented by CC-A2 and derived variants. Geographic distribution patterns of haplogroup II haplotypes and the nested position of CC-A11.6 from Oman among the Atlantic haplotypes invoke recent colonization of the Indian Ocean from the Atlantic for both global lineages. The haplotypes we confirmed for western Indian Ocean RMUs allow reinterpretation of previous mixed stock analysis and further suggest that contemporary migratory connectivity between the Indian and Atlantic Oceans occurs on a broader scale than previously hypothesized. This study represents a valuable model for conducting comprehensive international cooperative data management and research in marine ecology.  相似文献   
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Physical and chemical analyses of beer residues recovered from a vat site at Hierakonpolis (Upper Egypt) were carried out. Radiocarbon dates of the residues suggest a dating of 3500–3400 cal B.C. and are believed to represent the oldest known beer in the world. Macroscopic and microscopic examinations of the residues revealed the presence of intact remains of grains and spikelets of wheat and barley, as well as fragments of dates and grape pips. Chemical analyses included percentages of sample ingredients, pH and total soluble ions, quantitative determinations of sugars, carboxylic acids and free amino acids. A total of 25 compounds were identified, which are components of fermentation processes that are believed to have formed in connection with the preparation of what is called Nekhen-Hoffman beer.  相似文献   
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In this study we report the synthesis, characterization, biological evaluation, and druglikeness assessment of a series of 20 novel isoxazolyl-sulfonamides, obtained by a four-step synthetic route. The compounds had their activity against Trypanosoma cruzi, Leishmania amazonensis, Herpes Simplex Virus type 1 and cytotoxicity evaluated in phenotypic assays. All compounds have drug-like properties, showed low cytotoxicity and were promising regarding all other biological activities reported herein, especially the inhibitory activity against T. cruzi. The compounds 8 and 16 showed significant potency and selectivity against T. cruzi (GI50?=?14.3?µM, SI?>?34.8 and GI50?=?11.6?µM, SI?=?29.1, respectively). These values, close to the values of the reference drug benznidazole (GI50?=?10.2?µM), suggest that compounds 8 and 16 represent promising candidates for further pre-clinical development targeting Chagas disease.  相似文献   
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