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41.
(?)-Codeine 1 was converted into previously unknown 7β-methyl-7,8-dihydrocodeine/morphine derivatives such as 13 via classical diaxial opening of α-epoxide 3. Several analogs exhibited dual μ/δ-agonist activity.  相似文献   
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Coronary artery disease (CAD) is a multicellular disease characterized by chronic inflammation. Peripheral blood-mononuclear cells (PBMCs), as a critical component of immune system, actively cross-talk with pathophysiological conditions induced by endothelial cell injury, reflecting in perturbed PBMC expression. STAT1 is believed to be relevant to CAD pathogenesis through regulating key inflammatory processes and modulating STAT1 expression play key roles in fine-tuning CAD-related inflammatory processes. This study evaluated PBMC expressions of STAT1, and its regulators (miR-150 and miR-223) in a cohort including 72 patients with CAD with significant ( ≥ 50%) stenosis, 30 patients with insignificant ( < 50%) coronary stenosis (ICAD), and 74 healthy controls, and assessed potential of PBMC expressions to discriminate between patients and controls. We designed quantitative real-time polymerase chain reaction (RT-qPCR) assays and identified stable reference genes for normalizing PBMC quantities of miR-150, miR-223, and STAT1 applying geNorm algorithm to six small RNAs and five mRNAs. There was no significant difference between CAD and ICAD patients regarding STAT1 expression. However, both groups of patients had higher levels of STAT1 than healthy controls. miR-150 and miR-223 were differently expressed across three groups of subjects and were downregulated in patients compared with healthy controls, with the lowest expression levels being observed in patients with ICAD. ROC curves suggested that PBMC expressions may separate between different groups of study subjects. PBMC expressions also discriminated different clinical manifestations of CAD from ICADs or healthy controls. In conclusion, the present study reported PBMC dysregulations of STAT1, miR-150, and miR-223, in patients with significant or insignificant coronary stenosis and suggested that these changes may have diagnostic implications.  相似文献   
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Grapes (Vitis vinifera) are a valuable fruit crop and wine production is a major industry. Global warming and expanded range of cultivation will expose grapes to more temperature stresses in future. Our study investigated protein level responses to abiotic stresses, with particular reference to proteomic changes induced by the impact of four different temperature stress regimes, including both hot and cold temperatures, on cultured grape cells. Cabernet Sauvignon cell suspension cultures grown at 26°C were subjected to 14 h of exposure to 34 and 42°C for heat stress, and 18 and 10°C for cold stress. Cells from the five temperatures were harvested in biological triplicates and label‐free quantitative shotgun proteomic analysis was performed. A total of 2042 non‐redundant proteins were identified from the five temperature points. Fifty‐five proteins were only detected in extreme heat stress conditions (42°C) and 53 proteins were only detected at extreme cold stress conditions (10°C). Gene Ontology (GO) annotations of differentially expressed proteins provided insights into the metabolic pathways that are involved in temperature stress in grape cells. Sugar metabolism displayed switching between alternative and classical pathways during temperature stresses. Additionally, nine proteins involved in the phenylpropanoid pathway were greatly increased in abundance at extreme cold stress, and were thus found to be cold‐responsive proteins. All MS data have been deposited in the ProteomeXchange with identifier PXD000977 ( http://proteomecentral.proteomexchange.org/dataset/PXD000977 ).  相似文献   
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BioMetals - Small molecules have potential usage in cancer therapy due to their remarkable potency of disarranging the natural structure of nucleic acids. In this study, two complexes...  相似文献   
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Ureteral peristaltic mechanism facilitates urine transport from the kidney to the bladder. Numerical analysis of the peristaltic flow in the ureter aims to further our understanding of the reflux phenomenon and other ureteral abnormalities. Fluid-structure interaction (FSI) plays an important role in accuracy of this approach and the arbitrary Lagrangian-Eulerian (ALE) formulation is a strong method to analyze the coupled fluid-structure interaction between the compliant wall and the surrounding fluid. This formulation, however, was not used in previous studies of peristalsis in living organisms. In the present investigation, a numerical simulation is introduced and solved through ALE formulation to perform the ureteral flow and stress analysis. The incompressible Navier-Stokes equations are used as the governing equations for the fluid, and a linear elastic model is utilized for the compliant wall. The wall stimulation is modeled by nonlinear contact analysis using a rigid contact surface since an appropriate model for simulation of ureteral peristalsis needs to contain cell-to-cell wall stimulation. In contrast to previous studies, the wall displacements are not predetermined in the presented model of this finite-length compliant tube, neither the peristalsis needs to be periodic. Moreover, the temporal changes of ureteral wall intraluminal shear stress during peristalsis are included in our study. Iterative computing of two-way coupling is used to solve the governing equations. Two phases of nonperistaltic and peristaltic transport of urine in the ureter are discussed. Results are obtained following an analysis of the effects of the ureteral wall compliance, the pressure difference between the ureteral inlet and outlet, the maximum height of the contraction wave, the contraction wave velocity, and the number of contraction waves on the ureteral outlet flow. The results indicate that the proximal part of the ureter is prone to a higher shear stress during peristalsis compared with its middle and distal parts. It is also shown that the peristalsis is more efficient as the maximum height of the contraction wave increases. Finally, it is concluded that improper function of ureteropelvic junction results in the passage of part of urine back flow even in the case of slow start-up of the peristaltic contraction wave.  相似文献   
46.
In this review we examine techniques, software, and statistical analyses used in label-free quantitative proteomics studies for area under the curve and spectral counting approaches. Recent advances in the field are discussed in an order that reflects a logical workflow design. Examples of studies that follow this design are presented to highlight the requirement for statistical assessment and further experiments to validate results from label-free quantitation. Limitations of label-free approaches are considered, label-free approaches are compared with labelling techniques, and forward-looking applications for label-free quantitative data are presented. We conclude that label-free quantitative proteomics is a reliable, versatile, and cost-effective alternative to labelled quantitation.  相似文献   
47.
In the budding yeast Saccharomyces cerevisiae, progress of the cell cycle beyond the major control point in G1 phase, termed START, requires activation of the evolutionarily conserved Cdc28 protein kinase by direct association with GI cyclins. We have used a conditional lethal mutation in CDC28 of S. cerevisiae to clone a functional homologue from the human fungal pathogen Candida albicans. The protein sequence, deduced from the nucleotide sequence, is 79% identical to that of S. cerevisiae Cdc28 and as such is the most closely related protein yet identified. We have also isolated from C. albicans two genes encoding putative G1 cyclins, by their ability to rescue a conditional GI cyclin defect in S. cerevisiae; one of these genes encodes a protein of 697 amino acids and is identical to the product of the previously described CCN1 gene. The second gene codes for a protein of 465 residues, which has significant homology to S. cerevisiae Cln3. These data suggest that the events and regulatory mechanisms operating at START are highly conserved between these two organisms.  相似文献   
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Exhausted T cells and regulatory T (Treg) cells have been recently proposed to be new risk factors for recurrent miscarriage (RM). Intravenous immunoglobulin G (IVIG) treatment reported to modulate various immune cells. In this study, the effects of IVIG on the frequency and function of exhausted T cells, exhausted Tregs, and Treg cells, as well as pregnancy outcome in women with unexplained RM (URM), were investigated. Ninety-four pregnant women with RM were enrolled. At the time of positive pregnancy, blood samples were drawn. Forty-four patients with URM were included as IVIG receiving treated group and received 400 mg/kg of IVIG and the rest fifty patients were considered as a control group and received no IVIG administration. IVIG was given intravenously every 4 weeks during 32 weeks of gestation. Blood samples of patients were collected after the latest administration. Exhausted T cells, exhausted Tregs, and Treg cells were evaluated pre- and posttreatment in both groups. IVIG induced a significant decrease in the frequency of exhausted Tregs population and function as well as a significant increase in Treg cells population, however, IVIG failed to affect population and the function of exhausted T cells. Pregnancy outcome was successful in IVIG treated women (86.3%) and were significantly different (P = 0.0006) in compared with the untreated URM subjects (42%). Therefore, employing of IVIG increases Treg cells and diminishes exhausted Tregs responses in RM patients with cellular immune anomalies throughout the pregnancy. Immunemodulatory effects of IVIG are probably associated with successful pregnancy outcome.  相似文献   
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