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71.
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The roles of adipokines, proinflammatory cytokines, and adipose tissue macrophages in obesity-associated insulin resistance have been explored in both animal and human studies. However, our current understanding of obesity-associated insulin resistance relies on studies of artificial metabolic extremes. The purpose of this study was to explore the roles of adipokines, proinflammatory cytokines, and adipose tissue macrophages in human patients with modest obesity and early metabolic dysfunction. We obtained omental adipose tissue and fasting blood samples from 51 females undergoing gynecologic surgery. We investigated serum concentrations of proinflammatory cytokines and adipokines as well as the mRNA expression of proinflammatory and macrophage phenotype markers in visceral adipose tissue using ELISA and quantitative RT-PCR. We measured adipose tissue inflammation and macrophage infiltration using immunohistochemical analysis. Serum levels of adiponectin and leptin were significantly correlated with HOMA-IR and body mass index. The levels of expression of MCP-1 and TNF-α in visceral adipose tissue were also higher in the obese group (body mass index ≥ 25). The expression of mRNA MCP-1 in visceral adipose tissue was positively correlated with body mass index (r = 0.428, p = 0.037) but not with HOMA-IR, whereas TNF-α in visceral adipose tissue was correlated with HOMA-IR (r = 0.462, p = 0.035) but not with body mass index. There was no obvious change in macrophage phenotype or macrophage infiltration in patients with modest obesity or early metabolic dysfunction. Expression of mRNA CD163/CD68 was significantly related to mitochondrial-associated genes and serum inflammatory cytokine levels of resistin and leptin. These results suggest that changes in the production of inflammatory biomolecules precede increased immune cell infiltration and induction of a macrophage phenotype switch in visceral adipose tissue. Furthermore, serum resistin and leptin have specific roles in the regulation of adipose tissue macrophages in patients with modest obesity or early metabolic dysfunction.  相似文献   
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74.
An enriched consortium obtained from lake-sediment was developed for the removal of heavy metals such as Cu, Pb, Cr, Ni, and Zn from heavy metal-contaminated water. The removal efficiency of heavy metals in a shaking condition was generally higher than that in the static state. After the fifteenth enrichment with assorted heavy metals, the removal efficiencies in the shaking and static condition at an average concentration of 100 mg/L of each heavy metal were approximately 99 approximately 100% and 95 approximately 100%, respectively, depending on the type of heavy metal. An aerobically grown, pure culture isolated from an enriched culture was analyzed by 16S rRNA sequencing and identified as Ralstonia sp. HM-1. This strain was found to remove various heavy metals with an efficiency of approximately 97 approximately 100% at an average concentration of 200 mg/L of each heavy metal.  相似文献   
75.
A series of 3(R)-aminopyrrolidine derivatives were designed and synthesized for JAK1-selective inhibitors through the modification of tofacitinib’s core structure, (3R,4R)-3-amino-4-methylpiperidine. From the new core structures, we selected (R)-N-methyl-N-(pyrrolidin-3-yl)-7H-pyrrolo[2,3-d]pyrimidin-4-amine as a scaffold for further SAR studies. From biochemical enzyme assays and liver microsomal stability tests, (R)-3-(3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)pyrrolidin-1-yl)-3-oxopropanenitrile (6) was chosen for further in vivo test through oral administration. Compound 6 showed improved selectivity for JAK1 compared to that of tofacitinib (IC50 11, 2.4?×?102, 2.8?×?103, and 1.1?×?102?nM for JAK1, JAK2, JAK3, and TYK2, respectively). In CIA and AIA model tests, compound 6 exhibited similar efficacy to tofacitinib citrate.  相似文献   
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The voltage-gated potassium channel, Kv1.3, is present in human T-lymphocytes. Blockade of Kv1.3 results in T-cell depolarization, inhibition of T-cell activation, and attenuation of immune responses in vivo. A class of benzamide Kv1.3 channel inhibitors has been identified. The structure-activity relationship within this class of compounds in two functional assays, Rb_Kv and T-cell proliferation, is presented. In in vitro assays, trans isomers display moderate selectivity for binding to Kv1.3 over other Kv1.x channels present in human brain.  相似文献   
78.
ABSTRACT

Considering the effects of circadian misalignment on human pathophysiology and behavior, it is important to be able to detect an individual’s endogenous circadian time. We developed an endogenous Clock Estimation Model (eCEM) based on a machine learning process using the expression of 10 circadian genes. Hair follicle cells were collected from 18 healthy subjects at 08:00, 11:00, 15:00, 19:00, and 23:00 h for two consecutive days, and the expression patterns of 10 circadian genes were obtained. The eCEM was designed using the inverse form of the circadian gene rhythm function (i.e., Circadian Time = F(gene)), and the accuracy of eCEM was evaluated by leave-one-out cross-validation (LOOCV). As a result, six genes (PER1, PER3, CLOCK, CRY2, NPAS2, and NR1D2) were selected as the best model, and the error range between actual and predicted time was 3.24 h. The eCEM is simple and applicable in that a single time-point sampling of hair follicle cells at any time of the day is sufficient to estimate the endogenous circadian time.  相似文献   
79.
Endangered wolves cloned from adult somatic cells   总被引:1,自引:0,他引:1  
Over the world, canine species, including the gray wolf, have been gradually endangered or extinct. Many efforts have been made to recover and conserve these canids. The aim of this study was to produce the endangered gray wolf with somatic cell nuclear transfer (SCNT) for conservation. Adult ear fibroblasts from a female gray wolf (Canis lupus) were isolated and cultured in vitro as donor cells. Because of limitations in obtaining gray wolf matured oocytes, in vivo matured canine oocytes obtained by flushing the oviducts from the isthmus to the infundibulum were used. After removing the cumulus cells, the oocyte was enucleated, microinjected, fused with a donor cell, and activated. The reconstructed cloned wolf embryos were transferred into the oviducts of the naturally synchronized surrogate mothers. Two pregnancies were detected by ultrasonography at 23 days of gestation in recipient dogs. In each surrogate dog, two fetal sacs were confirmed by early pregnancy diagnosis at 23 days, but only two cloned wolves were delivered. The first cloned wolf was delivered by cesarean section on October 18, 2005, 60 days after embryo transfer. The second cloned wolf was delivered on October 26, 2005, at 61 days postembryo transfer. Microsatellite analysis was performed with genomic DNA from the donor wolf, the two cloned wolves, and the two surrogate female recipients to confirm the genetic identity of the cloned wolves. Analysis of 19 microsatellite loci confirmed that the cloned wolves were genetically identical to the donor wolf. In conclusion, we demonstrated live birth of two cloned gray wolves by nuclear transfer of wolf somatic cells into enucleated canine oocyte, indicating that SCNT is a practical approach for conserving endangered canids.  相似文献   
80.
Twenty-five bacterial strains that secrete mucous materials were isolated from sediment obtained from King George Island, Antarctica. Seven of these strains proved capable of producing cryoprotective exopolysaccharides. The strain KOPRI 21653 was selected for the further study of an anti-ice-nucleating polysaccharide (ANP), which originated from a polar region. KOPRI 21653 was identified as Pseudoalteromonas arctica as the result of 16S rRNA analysis. The exopolysaccharide, P-21653, was purified completely from the KOPRI 21653 cell culture via column chromatography and protease treatment. The principal sugar components of P-21653 were determined to be galactose and glucose, at a ratio of 1:1.5, via GC-MS analysis. The cryoprotective activity of P-21653 was characterized via an E. coli viability test. In the presence of 0.1% (w/v) P-21653, the survival ratio of E. coli cells was as high as 82.6% over three repeated freeze-thaw cycles. The survival ratio decreased drastically to 71.5 and 48.1%, respectively, in five and seven repeated cycle conditions; however, the survival ratios were greater over three (96.6-92.1%) to seven (100.5-91.6%) freeze-thaw cycles in the presence of 0.5 and 1.0% (w/v) P-21653. In addition, at much lower concentrations (0.1-1.0%), P-21653 resulted in survival ratios (83.1-98.4%) similar to those of two commercially available cryoprotectants (VEG plus X-1000, 92.9% and VM3, 95.3%), which were utilized at the recommended concentrations (90%). The biochemical characteristics of exopolysaccharide P-21653 reflect that this compound may be developed as a useful cryoprotectant for use in medical applications and in the food industry.  相似文献   
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