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A novel series of tacrine based cyclopentapyranopyridine- and tetrahydropyranoquinoline-kojic acid derivatives were designed, synthesized, and evaluated as anti-cholinesterase agents. The chemical structures of all target compounds were characterized by 1H-NMR, 13C-NMR, and elemental analyses. The synthesized compounds mostly inhibited acetylcholinesterase enzyme (AChE) with IC50 values of 4.18–48.71 μM rather than butyrylcholinesterase enzyme (BChE) with IC50 values of >100 μM. Among them, cyclopentapyranopyridine-kojic acid derivatives showed slightly better AChE inhibitory activity compared to tetrahydropyranoquinoline-kojic acid. The compound 10-amino-2-(hydroxymethyl)-11-(4-isopropylphenyl)-7,8,9,11-tetrahydro-4H-cyclopenta[b]pyrano[2′,3′ : 5,6]pyrano[3,2-e]pyridin-4-one ( 6f ) bearing 4-isopropylphenyl moiety and cyclopentane ring exhibited the highest anti-AChE activity with IC50 value of 4.18 μM. The kinetic study indicated that the compound 6f acts as a mixed inhibitor and the molecular docking studies also illustrated that the compound 6f binds to both the catalytic site (CS) and peripheral anionic site (PAS) of AChE. The compound 6f showed moderate neuroprotective properties against H2O2-induced cytotoxicity in PC12 cells. The theoretical ADME study also predicted good drug-likeness for the compound 6f . Based on these results, the compound 6f seems to be a very promising AChE inhibitor for the treatment of Alzheimer's disease.  相似文献   
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BackgroundThe accepted rate rate of caesarean section is 15%. It is expected that an increase in the density of midwives in the family physician program lead to a decrease in this indicator. This study aimed to compare the rates of caesarean section and women''s awareness and preference for mode of delivery before and after the implementation of the family physician program in health centres with and without an increase in midwives density.MethodsIn this cross-sectional study, using multistage cluster sampling method a total of 668 mothers with two-month-old children were selected from among all mothers with two-month-old children who were living in rural areas of Kurdistan province. Using the difference-in-differences model and Matchit statistical model, the factors associated with caesarean section rates and women''s awareness and preference for mode of delivery were compared in centres with and without an increase in midwives density after the implementation of the family physician program. To compare the changes before and after the program, we used the data collected from the same number of women in 2005 as the baseline.ResultsAfter adjusting for baseline data collected in 2005, the resutls showed no significant change in caesarean section rates and women''s awareness and preference for mode of delivery in the centres with and without an increase in midwives density after the implementation of the family physician program. The Matchit model showed a significant mean increase 14%(0.03–0.25) in women’s awareness of the benefits of natural childbirth between 2005 and 2013 in health centres where the density of midwives increased compared with health centres where it did not. The difference-in-differences model showed that the odds ratio of women’s preference for caesarean section decreased by 41% among participants who were aware of the benefits of natural childbirth, (OR = 0.59, 95% CI: (0.22–0.85); P>0.001).ConclusionsThe results of this study showed that an increase in the density of midwives in the family physician program led to an increase in women''s awareness of the benefits of natural childbirth. An increase in women’s awareness of the benefits of natural childbirth was associated with a decreased preference for caesarean section, however this reduction did not have a significant impact on caesarean section rates; possibly, this finding might be attributed to the complexity of this problem that needs a mixed strategy involving various stockholders.  相似文献   
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Background information. Within the group of lysosomal storage diseases, NPC1 [NPC (Niemann‐Pick type C) 1] disease is a lipidosis characterized by excessive accumulation of free cholesterol as well as gangliosides, glycosphingolipids and fatty acids in the late E/L (endosomal/lysosomal) system (Chen et al., 2005 ) due to a defect in late endosome lipid egress. We have previously demonstrated that expression of the small GTPase Rab9 in NPC1 cells can rescue the lipid transport block phenotype (Walter et al., 2003 ), albeit by an undefined mechanism. Results. To investigate further the mechanism by which Rab9 facilitates lipid movement from late endosomes we sought to identify novel Rab9 binding/interacting proteins. In the present study, we report that Rab9 interacts with the intermediate filament phosphoprotein vimentin and this interaction is altered by lipid accumulation in late endosomes, which results in inhibition of PKC (protein kinase C) and hypophosphorylation of vimentin, leading to late endosome dysfunction. Intermediate filament hypophosphorylation, aggregation and entrapment of Rab9 ultimately leads to transport defects and inhibition of lipid egress from late endosomes. Conclusions. These results reveal a previously unappreciated interaction between Rab proteins and intermediate filaments in regulating intracellular lipid transport.  相似文献   
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Nanofibrous scaffolds have been recently used in the field of tissue engineering because of their nano-size structure which promotes cell attachment, function, proliferation and infiltration. In this study, nanofibrous polyethersulfone (PES) scaffolds was prepared via electrospinning. The scaffolds were surface modified by plasma treatment and collagen grafting. The surface changes then investigated by contact angle measurements and FTIR-ATR. The results proved grafting of the collagen on nanofibers surface and increased hydrophilicity after plasma treatment and collagen grafting. The cell interaction study was done using stem cells because of their ability to differentiate to different kinds of cell lines. The cells had normal morphology on nanofibers and showed very high infiltration through collagen grafted PES nanofibers. This infiltration capability is very useful and needed to make 3D scaffolds in tissue engineering.  相似文献   
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The present study was designed to explore the mechanism of action of walnut (the seed of Juglans regia) leaf and ridge on hepatic glucose metabolism in diabetic mice. Experimental diabetes was induced by intravenous administration of streptozotocin (60 mg/kg)and confirmed with an increase of blood glucose, 90–100% of the control, 72 hours later. Isolated extracts from walnut leaf and ridges were administered in a single effective dose of 400 mg/kg orally. Firstly, blood glucose was determined every 1 hour until 5 hours post administration of extracts. In the second experiment, the liver was surgically removed, 2 hours post treatment of diabetic animals with extracts, homogenized and used for measurement of key enzymes of glycogenolysis (glycogen phosphorylase, GP) and gluconeogenesis (phosphoenolpyruvate carboxykinase, PEPCK). Treatment by both leaf and ridge extracts decreased blood glucose and liver PEPCK activity and increased blood insulin and liver GP activity. It is concluded that walnut is able to lower blood glucose through inhibition of hepatic gluconeogenesis and secretion of pancreatic insulin.  相似文献   
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