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671.
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Blood transfusion or blood products, such as plasma, have a long history in improving health, but today, platelet-rich plasma (PRP) is used in various medical areas such as surgery, orthopedics, and rheumatology in many ways. Considering the high efficiency of tissue engineering in repairing bone defects, in this study, we investigated the combined effect of nanofibrous scaffolds in combination with PRP on the osteogenic differentiation potential of human induced pluripotent stem cells (iPSCs). Electrospinning was used for fabricating nanofibrous scaffolds by polyvinylidene fluoride/collagen (PVDF/col) with and without PRP. After scaffold characterization, the osteoinductivity of the fabricated scaffolds was studied by culturing human iPSCs under osteogenic medium. The results showed that PRP has a considerable positive effect on the biocompatibility of the PVDF/col nanofibrous scaffold when examined by protein adsorption, cell attachment, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. In addition, the results obtained from alkaline phosphatase activity and calcium content assays demonstrated that nanofibers have higher osteoinductivity while grown on PRP-incorporated PVDF/col nanofibers. These results were also confirmed while the osteogenic differentiation of the iPSCs was more investigated by evaluating the most important bone-related genes expression level. According to the results, it can be concluded that PVDF/col/PRP has much more osteoinductivity while compared with the PVDF/col, and it can be introduced as a promising bone bio-implant for use in bone tissue engineering applications.  相似文献   
673.
MicroRNAs (miRNAs) are a class of small endogenous non-coding RNAs that modulate gene expression in both plants and animals and are involved in several biological processes, ranging from organ differentiation to biotic and abiotic stress responses. We identified two cold stress response microRNAs that showed differential expression in Solanum lycopersicum plants subjected to cold stress. We observed that Sly-miR166 and Sly-miR319 were up-regulated by cold treatments. The up-regulation of Sly-miR166 and Sly-miR319 in cold stress-treated S. lycopersicum seedlings and the down-regulation of their respective targets, HD-Zip III and GAMyb-like that validate by 5′-RACE technique, suggests that these miRNAs play a critical role in regulating S. lycopersicum responses to cold stress.  相似文献   
674.
Oxidative damage is thought to play a pivotal role in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Glutathione-S-transferases (GSTs) are involved in cell protection against oxidative stress. We examined whether GSTM1, GSTT1, and GSTP1 polymorphisms are associated with NAFLD in a sample of the Iranian population. The current case-control study included 83 patients with NAFLD and 93 healthy subjects. The GSTM1 and GSTT1 polymorphisms were analyzed by multiplex polymerase chain reaction (PCR). The GSTP1 polymorphism was detected by tetra amplification refractory mutation system-PCR assay. The GSTM1-null genotype was significantly associated with the development of NAFLD (odds ratios [OR]=2.171, 95% confidence intervals [CI]=1.188-3.970, p=0.015). The GSTP1 Val allele was shown to be a risk factor for NAFLD (OR=1.739, 95% CI=1.089-2.777, p=0.024). The GSTT1 polymorphism was not significantly different between control and patient groups (p=0.221). This study showed that GSTM1 and GSTP1, but not GSTT1, genetic polymorphisms are associated with NAFLD in a sample of the Iranian population, and may be used to determine the risk of development of NAFLD.  相似文献   
675.
676.
Soil improvement is one of the major concerns in civil engineering. Therefore, a variety of approaches have been employed for different soil types. The loose granular soils and sediments have always imposed challenges due to their low strength and bearing capacity as well as presenting difficulties in drilling and excavation. Biomediated soil improvement, i.e., utilizing some bacteria to precipitate calcite on soil particles, has recently been introduced as a novel link of biotechnology and civil engineering to improve the problematic soils. Biogrout as a branch of biomediated soil improvement is based upon microbial calcium carbonate precipitation (MICP). In the present study, the Taguchi method with the aim of optimizing the process was utilized to design the experiments (DOE). A standard L9 orthogonal array with four parameters comprising bacterial cell concentration, molar concentration ratio of nutrient solution, curing time, and flow rate, each assigned to three levels, was selected. In this regard, soil samples were stabilized in sandy soil columns. Two-phase injections were conducted by injecting the bacterium Sporosarcina pasteurii PTCC 1642 in the first phase and nutrient in the second phase. Specimens were subjected to an unconfined compressive strength (UCS) test. ANOVA pointed out how effectual each parameter was. The most effective parameter was curing time, which accounted for 45.97% of the overall variance of the experimental data followed by bacterial cell concentration (22.01%), nutrient strength (19.98%), and flow rate (12.04%). Predicted UCS values for the optimum condition were validated in a confirmation test. Indeed, the UCS of the soil increased from 85 kPa in the control sample to 930 kPa for the optimally treated specimen. It was concluded that rather than curing time, the other parameters are almost equally influential in the applied injection procedure.  相似文献   
677.
The aerial parts of Salvia chloroleuca were collected at full flowering stage at Shahrestanak (Tehran province of Iran). The essential oil was isolated by hydrodistillation and analyzed by combination of capillary GC and GC-MS. Thirty-four components were identified, representing 98.5% of the total oil. beta-Pinene (10.6%), alpha-pinene (9.0%), beta-caryophyllene (9.0%), 1,8-cineole (9.0%) and carvacrol (7.9%) were the main components. The in vitro antimicrobial activity of the essential oil of S. chloroleuca was studied against seven Gram-positive and Gram-negative bacteria (Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, S. epidermidis, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae) and three fungi (Candida albicans, Saccharomyces cerevisiae and Aspergillus niger); the disc diffusion method and MIC values indicated that the oil exhibited moderate to high antimicrobial activity.  相似文献   
678.

The field of tissue engineering exploits living cells in a variety of ways to restore, maintain, or enhance tissues and organs. Between stem cells, human induced pluripotent stem cells (hiPSCs), are very important due to their wide abilities. Growth factors can support proliferation, differentiation, and migration of hiPSCs. Platelet-rich plasma (PRP) could be used as the source of growth factors for hiPSCs. In the present study, proliferation and neural differentiation of hiPSCs on surface-modified nanofibrous Poly-l-lactic acid (PLLA) coated with platelet-rich plasma was investigated. The results of in vitro analysis showed that on the surface, which was modified nanofibrous scaffolds coated with platelet-rich plasma, significantly enhanced hiPSCs proliferation and neural differentiation were observed. Whereas the MTT ([3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide]) results showed biocompatibility of surface-modified nanofibrous scaffolds coated with platelet-rich plasma and the usage of these modified nanoscaffolds in neural tissue engineering in vivo is promising for the future.

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679.
ObjectivesTo show that there is relation between neutrophil-to-lymphocyte ratio (NLR) and metabolic syndrome and also, its components.FindingsMetabolic syndrome is associated with elevated fasting blood glucose, increased blood pressure, central obesity, decreased high-density lipoprotein, and increased triglyceride levels. Because of its growing incidence and prevalence and the effect that it has on developing other noncommunicable diseases, the importance gets even more value. The prediction and control of this disease in its early stages and in the most inexpensive way is of crucial need. Due to the role of chronic low-grade inflammation in metabolic syndrome, cytokines and inflammatory factors (like interleukin-6 and tumor necrosis factor-α) play a critical role on this phenomenon. The NLR is an inflammatory marker that has an unchallenging availability and has a reasonable cost. The NLR is related to obesity, type 2 diabetes, hypertension, and blood cholesterol levels.ConclusionThis suggests that there may be a relationship between the NLR and metabolic syndrome. The NLR, as a low-grade inflammation marker, indicates a positive relationship with central obesity. Also, studies indicate that the incidence of diabetes, its severity, and its control are related to the NLR. Hypertension and hyperlipidemia can both be noticed with higher NLRs. This rapid review assesses the association between metabolic syndrome and the NLR.  相似文献   
680.
The vasopressin analogue 1-deamino-8-D-arginine vasopressin (DDAVP) causes an immediate, transient rise in plasma levels of von Willebrand factor (vWF) after its administration. Although it is recognized that vascular endothelial cells play an essential role in this process, the molecular basis of the response is not understood. We have investigated the phenomenon using human umbilical vein endothelial cells as an in vitro model. When normal individuals were stimulated with DDAVP, plasma from blood samples collected subsequently caused the release of vWF from cultured endothelial cells over a 24 h period (22-46% increase over baseline), compared to control plasma (5-17%). DDAVP added directly to the endothelial cells produced no increase in vWF release. When whole blood was treated in vitro with DDAVP, and the plasma subsequently added to endothelial cells, a significant increase in vWF secretion was found. Peripheral blood mononuclear cells were then tested. In the presence of DDAVP, an increased response occurred. Further fractionation of these cells showed that monocytes were largely responsible, causing an increased vWF release of 162% at 2 h. These observations were reinforced by finding that the supernatants of monocytes incubated with DDAVP were also effective in causing increased vWF release (118% compared to 58% for the control sample). Our studies suggest that DDAVP plays an indirect role in causing the release of vWF from endothelial cells, and that peripheral blood monocytes may act as intermediary target cells, which then produce factor(s) acting directly on endothelial cells.  相似文献   
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