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排序方式: 共有1422条查询结果,搜索用时 31 毫秒
31.
Akira Araumi Tsukasa Osaki Kazunobu Ichikawa Kosuke Kudo Natsuko Suzuki Sayumi Watanabe Masafumi Watanabe Tsuneo Konta 《Biochemistry and Biophysics Reports》2021
The choice of treatment for primary nephrotic syndrome depends on the pathologic type of the disorder. Renal biopsy is necessary for a definitive diagnosis, but it is burdensome for the patients, and can be avoided if tests could be performed using urine or plasma. In this study, we analyzed 100 urinary proteins, 141 plasma proteins, and 57 urine/plasma ratios in cases of diabetic nephropathy (DN; n = 11), minimal change nephrotic syndrome (MCNS; n = 14), and membranous nephropathy (MN; n = 23). We found that the combination of urinary retinol-binding protein 4 and SH3 domain-binding glutamic acid-rich-like protein 3 could distinguish between MCNS and DN, with an area under the curve (AUC) of 0.9740. On the other hand, a selectivity index (SI) based on serotransferrin and immunoglobulin G, which is often used in clinical practice, distinguished them with an AUC of 0.9091. Similarly, the combination of urinary afamin and complement C3 urine/plasma ratio could distinguish between MN and DN with an AUC of 0.9842, while SI distinguished them with an AUC of 0.8538. Evidently, the candidates identified in this study were superior to the SI method. Thus, the aim was to test these biomarkers for accurate diagnosis and to greatly reduce the burden on patients. 相似文献
32.
Soluble oligomeric amyloid-β (Aβ) has been suggested to impair synaptic and neuronal function, leading to neurodegeneration that is clinically observed as the memory and cognitive dysfunction characteristic of Alzheimer disease, while the precise mechanism(s) whereby oligomeric Aβ causes neurotoxicity remains unknown. Recently, the cellular prion protein (PrPC) was reported to be an essential co-factor in mediating the neurotoxic effect of oligomeric Aβ. Our recent study showed that Prnp−/− mice are resistant to the neurotoxic effect of oligomeric Aβ in vivo and in vitro. Furthermore, application of an anti-PrPC antibody or PrPC peptide was able to block oligomeric Aβ-induced neurotoxicity. These findings demonstrate that PrPC may be involved in neuropathologic conditions other than conventional prion diseases, i.e., Creutzfeldt-Jakob disease. 相似文献
33.
Gaku Takibuchi Hirotake Imanishi Mami Morimoto Kaori Ishikawa Kazuto Nakada Noriko Toyama-Sorimachi Yoshiaki Kikkawa Keizo Takenaga Jun-Ichi Hayashi 《Mitochondrion》2013,13(6):881-887
To examine whether polymorphic mtDNA mutations that do not induce significant respiration defects regulate phenotypes of tumor cells, we used mouse transmitochondrial tumor cells (cybrids) with nuclear DNA from C57BL/6 (B6) strain and mtDNA from allogenic C3H strain. The results showed that polymorphic mutations of C3H mtDNA in the cybrids induced hypoxia sensitivity, resulting in a delay of tumor formation on their subcutaneous inoculation into B6 mice. Therefore, the effects of polymorphic mutations in normal mtDNA have to be carefully considered, particularly when we apply the gene therapy to the embryos to replace their pathogenic mtDNA by normal mtDNA. 相似文献
34.
Susumu Kudo Minoru Kawarabayashi Mariko Ikeda Kazuo Tanishita 《Journal of Biorheology》2013,26(1-2):38-43
Recent studies suggest that the temporal gradient of shear stress that is generated by blood flow plays an important role in the pathology of arteriosclerosis. We focused on the temporal gradient of shear stress and measured the permeability of albumin under steady or pulsatile shear stress conditions. Porcine aortic endothelial cells were seeded on a membrane filter and subjected to steady or pulsatile shear stress (1 Hz) at 1 Pa for 48 h, and the permeability of albumin was measured over time. The permeability increased gradually under steady flow but increased acutely under pulsatile shear stress. In particular, the maximum permeability of albumin differed under these conditions. The value was 4.2 × 10?5 cm/s at 18 h under pulsatile shear stress and 2.8 × 10?5 cm/s at 48 h under steady shear stress. The permeable route of albumin was examined using isoproterenol, which decreases junctional permeability. The increase in albumin permeability with pulsatile shear stress was decreased by isoproterenol. These results suggest that the increased permeability of albumin with pulsatile shear stress was related to trafficking through paracellular junctions. Thus, pulsation may promote a mechanotransduction process that differs from that of steady shear stress, and these pulsation effects likely play an important role in the permeability of macromolecules. 相似文献
35.
Masashi Kato Mayuko Y. Kumasaka Shoko Ohnuma Akio Furuta Yoko Kato Hossain U. Shekhar Michiyo Kojima Yasuko Koike Nguyen Dinh Thang Nobutaka Ohgami Thuy Bich Ly Xiaofang Jia Husna Yetti Hisao Naito Gaku Ichihara Ichiro Yajima 《PloS one》2013,8(6)
Health risk for well drinking water is a worldwide problem. Our recent studies showed increased toxicity by exposure to barium alone (≤700 µg/L) and coexposure to barium (137 µg/L) and arsenic (225 µg/L). The present edition of WHO health-based guidelines for drinking water revised in 2011 has maintained the values of arsenic (10 µg/L) and barium (700 µg/L), but not elements such as manganese, iron and zinc. Nevertheless, there have been very few studies on barium in drinking water and human samples. This study showed significant correlations between levels of arsenic and barium, but not its homologous elements (magnesium, calcium and strontium), in urine, toenail and hair samples obtained from residents of Jessore, Bangladesh. Significant correlation between levels of arsenic and barium in well drinking water and levels in human urine, toenail and hair samples were also observed. Based on these results, a high-performance and low-cost adsorbent composed of a hydrotalcite-like compound for barium and arsenic was developed. The adsorbent reduced levels of barium and arsenic from well water in Bangladesh and Vietnam to <7 µg/L within 1 min. Thus, we have showed levels of arsenic and barium in humans and propose a novel remediation system. 相似文献
36.
37.
Koshiishi Yuichi Murata-Okubo Michiko Fujisawa Shin-ichiro Shimoi Gaku Hirayama Hiroki Kameyama Yuichi Souma Kousaku Wada Kenta 《Molecular biology reports》2020,47(4):2521-2527
Molecular Biology Reports - The emu (Dromaius novaehollandiae) is a useful poultry animal farmed for fat, meat, and eggs. Genetic structure and relationships among farmed emu populations in Japan... 相似文献
38.
Mohammad Badrul Anam Shah Adil Ishtiyaq Ahmad Mikiko Kudo Arif Istiaq Athary Abdulhaleem M. Felemban Naofumi Ito Kunimasa Ohta 《Development, growth & differentiation》2020,62(2):97-107
Specialized microenvironment, or neurogenic niche, in embryonic and postnatal mouse brain plays critical roles during neurogenesis throughout adulthood. The subventricular zone (SVZ) and the dentate gyrus (DG) of hippocampus in the mouse brain are two major neurogenic niches where neurogenesis is directed by numerous regulatory factors. Now, we report Akhirin (AKH), a stem cell maintenance factor in mouse spinal cord, plays a pivotal regulatory role in the SVZ and in the DG. AKH showed specific distribution during development in embryonic and postnatal neurogenic niches. Loss of AKH led to abnormal development of the ventricular zone and the DG along with reduction of cellular proliferation in both regions. In AKH knockout mice (AKH−/−), quiescent neural stem cells (NSCs) increased, while proliferative NSCs or neural progenitor cells decreased at both neurogenic niches. In vitro NSC culture assay showed increased number of neurospheres and reduced neurogenesis in AKH−/−. These results indicate that AKH, at the neurogenic niche, exerts dynamic regulatory role on NSC self-renewal, proliferation and differentiation during SVZ and hippocampal neurogenesis. 相似文献
39.
Naoyuki Okita Miyuki Yoshimura Kazuhito Watanabe Shota Minato Yuki Kudo Yoshikazu Higami Sei-ichi Tanuma 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
CHK1 is an important effector kinase that regulates the cell cycle checkpoint. Previously, we showed that CHK1 is cleaved in a caspase (CASP)-dependent manner during DNA damage-induced programmed cell death (PCD) and have examined its physiological roles.Methods and results
In this study, we investigated the behavior of CHK1 in PCD. Firstly, we found that CHK1 is cleaved at three sites in PCD, and all cleavages were inhibited by the co-treatment of a pan-CASP inhibitor or serine protease inhibitors. We also showed that CHK1 is cleaved by CASP3 and/or CASP7 recognizing at 296SNLD299 and 348TCPD351, and that the cleavage results in the enhancement of CHK1 kinase activity. Furthermore, as a result of the characterization of cleavage sites by site-directed mutagenesis and an analysis performed using deletion mutants, we identified 320EPRT323 as an additional cleavage recognition sequence. Considering the consensus sequence cleaved by CASP, it is likely that CHK1 is cleaved by non-CASP family protease(s) recognizing at 320EPRT323. Additionally, the cleavage catalyzed by the 320EPRT323 protease(s) markedly and specifically increased when U2OS cells synchronized into G1 phase were induced to PCD by cisplatin treatment.Conclusion
CHK1 cleavage is directly and indirectly regulated by CASP and non-CASP family proteases including serine protease(s) and the “320EPRT323 protease(s).” Furthermore, 320EPRT323 cleavage of CHK1 occurs efficiently in PCD which is induced at the G1 phase by DNA damage.General significance
CASP and non-CASP family proteases intricately regulate cleavage for up-regulation of CHK1 kinase activity during PCD. 相似文献40.
Kyosuke Takabe Shuichi Nakamura Masamichi Ashihara Seishi Kudo 《Microbiology and immunology》2013,57(3):236-239
The motility of bacteria is an important factor in their infectivity. In this study, the motility of Leptospira, a member of the spirochete family that causes a zoonotic disease known as leptospirosis, was analyzed in different viscous or osmotic conditions. Motility assays revealed that both pathogenic and saprophytic strains increase their swimming speeds with increasing viscosity. However, only pathogenic Leptospira interrogans maintained vigorous motility near physiological osmotic conditions. This suggests that active motility in physiological conditions is advantageous when Leptospira enters hosts and when it migrates toward target tissues. 相似文献