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101.
The contribution of genetic factors to blood pressure levels is well established. The contribution of genes to the longitudinal change in blood pressure has been less well studied, because of the lack of longitudinal family data. The present study investigated a possible major-gene effect on the observed increase with age in diastolic blood pressure (DBP) levels. Subjects included 965 unmedicated adults (age > or = 18 years) in 73 pedigrees collected in Utah as part of a longitudinal cardiovascular family study. Segregation analysis of DBP change over 7.2 years of follow-up identified a recessive major-gene effect with a gene frequency of p = .23. There was also a significant age effect on the genotypic means, which decreased expression of the major gene at older ages. For those inferred to have the genotype responsible for large DBP increases, DBP increased 32.3%, compared with a 1.5% increase in the nonsusceptible group (P < .0001). The relative risk of developing hypertension between the susceptible and nonsusceptible groups after 7.2 years was 2.4 (P = .006). Baseline DBP reactivities to mental arithmetic (P < .0001), and isometric handgrip (P < .0001) stress tests were greatest in those assigned to the susceptible genotype. We conclude that age-related changes in DBP are influenced by a major gene. Characteristics of this major-gene effect for greater age-related blood pressure increases include greater reactivity to mental and physical stressors. The present study thus provides evidence for genetic control of changes in blood pressure, in addition to the previously suggested genetic control of absolute blood pressure level.  相似文献   
102.
Aseptic loosening is the most common long-term complication of total joint replacement, which is associated with the generation of wear debris. The purpose of this study was to investigate the inhibitory effect of small interfering RNA (siRNA) targeting tumor necrosis factor-α (TNF-α) on wear debris-induced inflammation. A local delivery of lentivirus-mediated TNF-α siRNA into the modified murine air pouch, which was stimulated by polymethylmethacrylate (PMMA) particles, resulted in significant blockage of TNF-α both in mRNA and protein levels for up to 4 weeks. In addition, significant down-regulation of interleukin-1 (IL-1) and interleukin-6 (IL-6) was observed in TNF-α siRNA-treated pouches. The safety profile of gene therapy was proven by Bioluminescent assay and quantitative fluorescent flux. Histological analysis revealed less inflammatory responses (thinner pouch membrane and decreased cellular infiltration) in TNF-α siRNA-treated pouches. These findings suggest that local delivery of TNF-α siRNA might be an excellent therapeutic candidate to inhibit particle-induced inflammation.  相似文献   
103.
104.
Use of historical data and real-world evidence holds great potential to improve the efficiency of clinical trials. One major challenge is to effectively borrow information from historical data while maintaining a reasonable type I error and minimal bias. We propose the elastic prior approach to address this challenge. Unlike existing approaches, this approach proactively controls the behavior of information borrowing and type I errors by incorporating a well-known concept of clinically significant difference through an elastic function, defined as a monotonic function of a congruence measure between historical data and trial data. The elastic function is constructed to satisfy a set of prespecified criteria such that the resulting prior will strongly borrow information when historical and trial data are congruent, but refrain from information borrowing when historical and trial data are incongruent. The elastic prior approach has a desirable property of being information borrowing consistent, that is, asymptotically controls type I error at the nominal value, no matter that historical data are congruent or not to the trial data. Our simulation study that evaluates the finite sample characteristic confirms that, compared to existing methods, the elastic prior has better type I error control and yields competitive or higher power. The proposed approach is applicable to binary, continuous, and survival endpoints.  相似文献   
105.
Kamal  Osama M.  Shah  Sayyed Hamad Ahmad  Li  Yan  Hou  Xilin  Li  Ying 《Molecular biology reports》2020,47(9):6887-6897
Molecular Biology Reports - The objective of the present work was the selection of cultivar, suitable medium and explant type for callus, root production, ascorbic acid, total ascorbic acid,...  相似文献   
106.
Human complement protein C8 was labeled with the fluorescent chromophores fluorescein-5-isothiocyanate (FITC), 3-(4-isothiocyanatophenyl)-7-diethylamine-4-methyl coumarin (IPM), eosin-5-isothiocyanate (EOS), or Texas Red (sulforhodamine-101-sulfonyl chloride; TR) with only minor reduction in the specific hemolytic activity of the protein. The distribution of C5b-8 complexes bound to sheep erythrocyte membranes was investigated by monitoring fluorescence resonance energy transfer (RET) between the following RET donor/acceptor pairs of labeled C8: FITC-C8/EOS-C8, IPM-C8/EOS-C8, and FITC-C8/TR-C8. On binding to membranes containing pre-formed C5b67 complexes, specific RET was detected for each of the donor/acceptor pairs of labeled C8 investigated. In contrast, no energy transfer was observed for these RET donor/acceptor pairs of labeled C8 incubated in the presence of control membranes or in membrane-free solution. On the basis of a consideration of the transfer efficiency that would be expected for donor/acceptor pairs of labeled C8 that were uniformly dispersed on the membrane surface, these results suggest that C5b-8 complexes are aggregated into polymeric clusters when membrane-bound. The efficiency of donor-C8 to acceptor-C8 RET--and the hemolytic activity of membrane-bound C5b-8 (in the absence of C9)--are both related to the surface density of membrane-bound C5b67, suggesting that the physical clustering of the membrane-inserted C5b-8 complex may be related to the expression of its cytolytic activity.  相似文献   
107.
The sugar alcohol mannitol and it’s catabolic enzyme mannitol dehydrogenase (MTD), in addition to welldocumented roles in metabolism and osmoprotection, may play roles in hostpathogen interactions. Research suggests that in response to the mannitol that pathogenic fungi secrete to suppress reactive oxygen-mediated host defenses, plants make MTD to catabolize fungal mannitol. Yet previous work suggested that pathogen-secreted mannitol is extracellular, while in healthy plants MTD is cytoplasmic. We have presented results showing that the normally cytoplasmic MTD is exported into the cell wall or extracellular space in response to the endogenous inducer of plant defense responses salicylic acid (SA). This SA-induced secretion is insensitive to brefeldin A, an inhibitor of Golgimediated protein transport. Together with the absence of MTD in Golgi stacks and the lack of a documented extracellular targeting sequence in the MTD protein, this suggests MTD is secreted by a non-Golgi, pathogen-activated secretion mechanism in plants. Here we discuss the potential significance of non-Golgi secretion in response to stress.Key words: protein secretion, mannitol metabolism, plant-pathogen interaction, extracellular space, apoplast  相似文献   
108.
109.
The purpose of the study was to investigate the anti-fibrotic effect and the potential mechanisms of action of betulinic acid (BA) against hepatic fibrosis in vivo and in vitro. BA is an active compound isolated from the bark of the birch tree Betula spp. (Betulaceae). Liver fibrosis was induced by intraperitoneal injections of thioacetamide (TAA, 200mg/kg) twice weekly for 6weeks in Wistar rats. The administration of BA (20 or 50mg/kg) was started following TAA injections and was continued for 6 or 8weeks to evaluate both the preventive and the protective effects. BA demonstrated great efficacy in preventing and curing hepatic fibrosis via attenuating the TAA-mediated increases in liver tissue hydroxyproline and α-smooth muscle actin (α-SMA). In vitro, BA effectively decreased the HSC-T6 cell viability induced by TNF-α and showed low toxicity in normal human chang liver cells. Moreover, BA significantly attenuated the expression of α-SMA and tissue inhibitor of metalloproteinase-1 (TIMP-1) and increased the levels of matrix metalloprotease (MMP)-13. BA also inhibited the expression of Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88) and the activation of nuclear factor-κB (NF-κB) in a time-dependent manner. This study provides evidence that BA exerts a significant anti-fibrosis effect by modulating the TLR4/MyD88/NF-κB signaling pathway.  相似文献   
110.
Endothelial dysfunction is a hallmark of inflammation and is mediated by inflammatory factors that signal through G protein–coupled receptors including protease-activated receptor-1 (PAR1). PAR1, a receptor for thrombin, signals via the small GTPase RhoA and myosin light chain intermediates to facilitate endothelial barrier permeability. PAR1 also induces endothelial barrier disruption through a p38 mitogen-activated protein kinase–dependent pathway, which does not integrate into the RhoA/MLC pathway; however, the PAR1-p38 signaling pathways that promote endothelial dysfunction remain poorly defined. To identify effectors of this pathway, we performed a global phosphoproteome analysis of thrombin signaling regulated by p38 in human cultured endothelial cells using multiplexed quantitative mass spectrometry. We identified 5491 unique phosphopeptides and 2317 phosphoproteins, four distinct dynamic phosphoproteome profiles of thrombin-p38 signaling, and an enrichment of biological functions associated with endothelial dysfunction, including modulators of endothelial barrier disruption and a subset of kinases predicted to regulate p38-dependent thrombin signaling. Using available antibodies to detect identified phosphosites of key p38-regulated proteins, we discovered that inhibition of p38 activity and siRNA-targeted depletion of the p38α isoform increased basal phosphorylation of extracellular signal–regulated protein kinase 1/2, resulting in amplified thrombin-stimulated extracellular signal–regulated protein kinase 1/2 phosphorylation that was dependent on PAR1. We also discovered a role for p38 in the phosphorylation of α-catenin, a component of adherens junctions, suggesting that this phosphorylation may function as an important regulatory process. Taken together, these studies define a rich array of thrombin- and p38-regulated candidate proteins that may serve important roles in endothelial dysfunction.  相似文献   
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