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We report a new form of congenital muscular dystrophy (CMD) in 4 patients from three unrelated families with probable autosomal-recessive inheritance. All patients had the clinical characteristics of merosin-positive congenital muscular dystrophy, but had marked mental retardation. The disease was slowly progressive and 1 patient died from dilated cardiomyopathy at the age of 13 years. In addition to dystrophic changes with necrosis and regeneration in muscle, the most striking finding was mitochondrial depletion in the center of the sarcoplasm. Mitochondria at the periphery of fibers were markedly enlarged ("megaconial" appearance) with complicated cristae, and contained a normal amount of mitochondrial DNA by in situ hybridization. Mitochondrial enlargement may represent functional compensation for mitochondrial depletion in the central sarcoplasm, where myofibrillar degeneration occurred. 相似文献
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Ji Hye Yang Sae Kwang Ku IL Je Cho Je Hyeon Lee Chang-Su Na Sung Hwan Ki 《International journal of molecular sciences》2021,22(4)
Hepatic fibrosis occurs when liver tissue becomes scarred from repetitive liver injury and inflammatory responses; it can progress to cirrhosis and eventually to hepatocellular carcinoma. Previously, we reported that neoagarooligosaccharides (NAOs), produced by the hydrolysis of agar by β-agarases, have hepatoprotective effects against acetaminophen overdose-induced acute liver injury. However, the effect of NAOs on chronic liver injury, including hepatic fibrosis, has not yet been elucidated. Therefore, we examined whether NAOs protect against fibrogenesis in vitro and in vivo. NAOs ameliorated PAI-1, α-SMA, CTGF and fibronectin protein expression and decreased mRNA levels of fibrogenic genes in TGF-β-treated LX-2 cells. Furthermore, downstream of TGF-β, the Smad signaling pathway was inhibited by NAOs in LX-2 cells. Treatment with NAOs diminished the severity of hepatic injury, as evidenced by reduction in serum alanine aminotransferase and aspartate aminotransferase levels, in carbon tetrachloride (CCl4)-induced liver fibrosis mouse models. Moreover, NAOs markedly blocked histopathological changes and collagen accumulation, as shown by H&E and Sirius red staining, respectively. Finally, NAOs antagonized the CCl4-induced upregulation of the protein and mRNA levels of fibrogenic genes in the liver. In conclusion, our findings suggest that NAOs may be a promising candidate for the prevention and treatment of chronic liver injury via inhibition of the TGF-β/Smad signaling pathway. 相似文献
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Bong Gu Lee Jun IL Yang Euna Kim Sun Woo Geum Ju-Hyeong Park Min-Kyeong Yeo 《Indoor air》2021,31(5):1553-1562
The advent of high-throughput sequencing methods allowed researchers to fully characterize microbial community in environmental samples, which is crucial to better understand their health effects upon exposures. In our study, we investigated bacterial and fungal community in indoor and outdoor air of nine classrooms in three elementary schools in Seoul, Korea. The extracted bacterial 16S rRNA gene and fungal ITS regions were sequenced, and their taxa were identified. Quantitative polymerase chain reaction for total bacteria DNA was also performed. The bacterial community was richer in outdoor air than classroom air, whereas fungal diversity was similar indoors and outdoors. Bacteria such as Enhydrobacter, Micrococcus, and Staphylococcus that are generally found in human skin, mucous membrane, and intestine were found in great abundance. For fungi, Cladosporium, Clitocybe, and Daedaleopsis were the most abundant genera in classroom air and mostly related to outdoor plants. Bacterial community composition in classroom air was similar among all classrooms but differed from that in outdoor air. However, indoor and outdoor fungal community compositions were similar for the same school but different among schools. Our study indicated the main source of airborne bacteria in classrooms was likely human occupants; however, classroom airborne fungi most likely originated from outdoors. 相似文献
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A. S. Bedekar J. J. Feng S. Krishnamoorthy - S. Krishnamoorthy is currently with Baxter Healthcare Corporation Round Lake IL. K. G. Lim G. T. R. Palmore S. Sundaram 《Chemical Engineering Communications》2008,195(3):256-266
Biofuel cells are devices that use biocatalysts (enzymes or microbes) to convert biochemical energy directly into electrical energy. Microfluidic biofuel cells exploit the lack of active mixing at microscale dimensions to eliminate the use of proton exchange membranes that separate anolyte and catholyte streams. Simulation of this system, by solving the governing 3-D conservation equations (flow, species transport), reveals that oxygen availability limits the performance of the cathode. An exponential decay in the availability of oxygen at the cathode is observed along the length of the microchannel, indicating that increasing the number of electrode pairs reduces the overall current density. This conclusion is consistent with experimental observations. Increasing electrolyte flow rates can reduce the mass transport limitations by decreasing the diffusion boundary-layer thickness, but disparity between the flow rates of the anolyte and catholyte can induce wastage of dissolved oxygen. 相似文献
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The physicochemical properties and antioxidant properties of bokbunja, a Korean black raspberry, were clarified and compared with blueberry, cranberry, raspberry, and strawberry. The amount of soluble solids was significantly (p<0.05) lower in bokbunja than in other berries, whereas the pH of bokbunja was significantly (p<0.05) higher. Analysis of the total phenolic, flavonoid, and anthocyanin contents found that bokbunja had the highest, while the others were ranked in the order of raspberry>blueberry>cranberry>strawberry. The content of ellagic acid (147.3 mg/100 g of FW) also was highest in bokbunja. The antioxidant activities of bokbunja, assessed based on DPPH, ABTS, and ferric reducing antioxidant power (FRAP) assays, were higher than for other berries. Bokbunja is a healthier antioxidant source than other berries. 相似文献
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四、第一代表面工程方法 1.固态淬火(硬化) 加热的各项工艺参数、材料的初始组织和机件的具体几何形状,都对材料的组织和性能、淬硬的深度和机件的表面质量有很大的影响。在我们的试验研究中,对各种不同的结构钢和工具钢以及某些铁进行了研究,采用的加热方式为将需要淬硬的整个表面同时加热等。对于退火状态的和整体淬硬的多,硬化度分别达到3.6~3.7和1.5~1.7。钢的硬度达到HRC65~68,显微硬度为10~11GPa,硬化的深度为 1.5-2.0mm。 在各种钢中,会产生残余的压缩应力,还会形成细粒组织,并… 相似文献
70.
MB Iarustovski? RG Grigor'iants VS Timokhov MV Abramian IL Mikha?lova SS Volkova IaV Banketov II Golenishchev II Iakovleva 《Canadian Metallurgical Quarterly》1997,(6):40-46
The efficacy of continuous methods of renal substitute therapy (RST) in patients with multiple organ failure is assessed. The patients were divided in 2 groups administered different types of PST. Group 1 were 16 patients subjected to RST by peritoneal dialysis, in group 2 (n = 16) GP and/or GDP were used. Hemodynamics, hematological and biochemical values, and clearance of inflammation mediators were monitored and hemohydrobalance and complications of therapy assessed in the course of RST. Both RST methods proved to be highly effective. The possibility of differentiated use of peritoneal dialysis and GP/GDP permits an individual approach to treatment, and equally high efficacy of both methods solves the problem of treating total renal insufficiency in the majority of patients with multiple organ failure following cardiovascular surgery. 相似文献