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991.
To address whether diabetes enhances lipid peroxidation and attenuates nitric oxide (NO) generation resulting in tissue complications, we measured oxysterols and NO metabolites (NOx) in the tissues of diabetic Wistar rats. After 4 weeks of streptozotocin injection (STZ, 80?mg/kg, i.p.), we measured 7α- and 7β-hydroperoxycholest-5-en-3β-ol (7α-OOH and 7β-OOH), 7α- and 7β-hydroxycholesterol (7α-OH and 7β-OH) and 7-ketocholesterol (7-keto) by HPLC in the kidneys, heart, and liver. All the oxysterols were much higher in the diabetic than in sham rats, while the extent of the increase was higher in the order of the kidney, heart, and liver. Together with high blood urea nitrogen, the data indicate that the kidney is the predominant target of early diabetic complications. Plasma NOx were decreased by 20% in the STZ rats. The enhanced oxidative stress in diabetes would increase oxysterols by peroxidation, while superoxide is known to reduce NO by reaction to form another potent oxidant peroxynitrite. 相似文献
992.
Koichi Ariyoshi Junko Adachi Migiwa Asano Yasuhiro Ueno Rajkumar Rajendram Victor R. Preedy 《Free radical research》2013,47(6):661-666
It was our hypothesis that, as a consequence of increased oxidative stress, cholesterol-derived hydroperoxides and oxysterols are increased in livers of rats exposed to ethanol. To test this we dosed Wistar rats (approximately 0.1 kg initial body weight) with ethanol chronically (rats fed a nutritionally complete liquid diet containing ethanol as 35% of total calories; sampled liver at approximately 6-7 weeks). We measured concentrations of 7 f - and 7 g -hydroperoxycholest-5-en-3 g -ol (7 f -OOH and 7 g -OOH) as well as 7 f - and 7 g -hydroxycholesterol (7 f -OH and 7 g -OH), and 3 g -hydroxycholest-5-en-7-one (also termed 7-ketocholesterol; 7-keto). In response to chronic alcohol feeding, there were significant elevations in the concentrations of 7 f -OOH (+169%, P =0.005 ) and 7 g -OOH (+199%, P =0.011 ). Increases in the concentrations of hepatic 7-keto (+74%, P =0.01 ) and decreases in cholesterol ( m 43%; P =0.03 ) also occurred. In contrast, the concentrations of both 7 f -OH and 7 g -OH were not significant (NS). However, when oxysterols in chronic ethanol-fed rats were expressed relative to cholesterol there were significant increases in 7-keto/cholesterol ( P =0.0006), 7 f -OH/cholesterol ( P =0.0018) and 7 g -OH/cholesterol ( P =0.0047). In conclusion, this is the first report of increased 7 f -OOH, 7 g -OOH, and 7-keto in liver of rats and their elevation in chronic experimental alcoholism represent evidence of increased oxidative stress. 相似文献
993.
Hiroyuki Matsui Kotaro Shirakawa Yoshinobu Konishi Shigeki Hirabayashi Anamaria Daniela Sarca Hirofumi Fukuda Ryosuke Nomura Emani Stanford Yoshihito Horisawa Yasuhiro Kazuma Tadahiko Matsumoto Hiroyuki Yamazaki Yasuhiro Murakawa Emilie Battivelli Eric Verdin Yoshio Koyanagi Akifumi Takaori-Kondo 《Journal of virology》2021,95(8)
994.
Yasuhiro Nonaka Takashi Ogawa Hiroki Shoji Nozomu Nishi Shigehiro Kamitori Takanori Nakamura 《Biochimica et Biophysica Acta - Proteins and Proteomics》2021,1869(10):140684
The galectin family is a representative soluble lectin group, which is responsible for the modulation of various cell functions. Although the carbohydrate-binding specificity of galectins has been well-studied, the relationship between protein structure and specificity remains to be elucidated. We previously reported the characteristics of a Xenopus laevis skin galectin, xgalectin-Va, which had diverged from galectin-1. The carbohydrate selectivity of xgalectin-Va was different from that of human galectin-1 and xgalectin-Ib (a Xenopus laevis galectin-1 homolog). In this study, we clarified the key residues for this selectivity by site-directed mutagenesis. Substitution of two amino acids of xgalectin-Va, Val56Gly/Lys76Arg, greatly enhanced the binding ability to N-acetyllactosamine and conferred significant T-cell growth inhibition activity, although the wild type had no activity. These two residues, Gly54 and Arg74 in galectin-1, would cooperatively contribute to the N-acetyllactosamine recognition. The loop region between the S4 and S5 β-strands was involved in the binding to the TF-antigen disaccharide. The loop substitution successfully changed the carbohydrate selectivity of xgalectin-Va and xgalectin-Ib. 相似文献
995.
Kusumoto Buntarou Kubota Yasuhiro Shiono Takayuki Villalobos Fabricio 《Biological invasions》2021,23(9):2973-2984
Biological Invasions - Understanding the mechanisms of biological invasion is fundamental for biodiversity conservation in the Anthropocene. This study focused on a large-scale colonization pattern... 相似文献
996.
Takeshi Tokida Minaco Adachi Weiguo Cheng Yasuhiro Nakajima Tamon Fumoto Miwa Matsushima Hirofumi Nakamura Masumi Okada Ryoji Sameshima Toshihiro Hasegawa 《Global Change Biology》2011,17(11):3327-3337
Quantification of rhizodeposition (root exudates and root turnover) represents a major challenge for understanding the links between above‐ground assimilation and below‐ground anoxic decomposition of organic carbon in rice paddy ecosystems. Free‐air CO2 enrichment (FACE) fumigating depleted 13CO2 in rice paddy resulted in a smaller 13C/12C ratio in plant‐assimilated carbon, providing a unique measure by which we partitioned the sources of decomposed gases (CO2 and CH4) into current‐season photosynthates (new C) and soil organic matter (old C). In addition, we imposed a soil‐warming treatment nested within the CO2 treatments to assess whether the carbon source was sensitive to warming. Compared with the ambient CO2 treatment, the FACE treatment decreased the 13C/12C ratio not only in the rice‐plant carbon but also in the soil CO2 and CH4. The estimated new C contribution to dissolved CO2 was minor (ca. 20%) at the tillering stage, increased with rice growth and was about 50% from the panicle‐formation stage onwards. For CH4, the contribution of new C was greater than for heterotrophic CO2 production; ca. 40–60% of season‐total CH4 production originated from new C with a tendency toward even larger new C contribution with soil warming, presumably because enhanced root decay provided substrates for greater CH4 production. The results suggest a fast and close coupling between photosynthesis and anoxic decomposition in soil, and further indicate a positive feedback of global warming by enhanced CH4 emission through greater rhizodeposition. 相似文献
997.
Amer S Dar Y Ichikawa M Fukuda Y Tada C Itagaki T Nakai Y 《Parasitology international》2011,60(1):5-12
Fascioliasis has a negative impact on the farming industry in both developed and developing countries, rather than a public health challenge. This study was performed to identify Fasciola sp. from different definitive hosts (buffalo, cattle, and sheep) based on the molecular parameters and spermatogenesis. Ninety-one adult flukes were collected from livers of slaughtered animals at abattoirs in different prefectures in Egypt. Microscopic examination of the analyzed flukes showed many normal spermatozoa in the seminal vesicles (spermic), suggesting that they have the ability of spermatogenesis. This study showed that no parthenogenic Fasciola species occurred in Egypt. Molecular analysis was performed utilizing genomic (ITS1 and ITS2) and mitochondrial (NDI and COI) gene markers. Whereas 16 animals proved to have infection with a single Fasciola species, 2 were infected with both F. hepatica and F. gigantica. The results indicated that sheep were prone to F. hepatica (8 out of 10 animals) more than F. gigantica infection. Sequences of ITS1 and ITS2 ribosomal region indicated that the flukes were categorized into 3 groups F. hepatica-type (47), F. gigantica-type (42) and 2 flukes possessed sequences of both types indicating an existence of different alleles at the same loci. Unique overlapping of T/C bases were detected in both ITS1 (Position 96) and ITS2 (Position 416). Based on results of mitochondrial gene markers (NDI and COI), flukes were classified into F. hepatica-type and F. gigantica-type. Extensive intra-sequence polymorphism was detected at both markers. NDI and COI sequences of Egyptian strain of F. gigantica showed pronounced diversity compared with relevant sequences at database. 相似文献
998.
Hiroyuki Taniguchi Yasuhiro Kondoh Masahito Ebina Arata Azuma Takashi Ogura Yoshio Taguchi Moritaka Suga Hiroki Takahashi Koichiro Nakata Atsuhiko Sato Yukihiko Sugiyama Shoji Kudoh Toshihiro Nukiwa 《Respiratory research》2011,12(1):1-9
Background
The rate of decline in forced expiratory volume in 1 second (FEV1) is representative of the natural history of COPD. Sparse information exists regarding the associations between the magnitude of annualised loss of FEV1 with other endpoints.Methods
Retrospective analysis of UPLIFT® trial (four-year, randomized, double-blind, placebo-controlled trial of tiotropium 18 μg daily in chronic obstructive pulmonary disease [COPD], n = 5993). Decline of FEV1 was analysed with random co-efficient regression. Patients were categorised according to quartiles based on the rate of decline (RoD) in post-bronchodilator FEV1. The St George's Respiratory Questionnaire (SGRQ) total score, exacerbations and mortality were assessed within each quartile.Results
Mean (standard error [SE]) post-bronchodilator FEV1 increased in the first quartile (Q1) by 37 (1) mL/year. The other quartiles showed annualised declines in FEV1 (mL/year) as follows: Q2 = 24 (1), Q3 = 59 (1) and Q4 = 125 (2). Age, gender, respiratory medication use at baseline and SGRQ did not distinguish groups. The patient subgroup with the largest RoD had less severe lung disease at baseline and contained a higher proportion of current smokers. The percentage of patients with ≥ 1 exacerbation showed a minimal difference from the lowest to the largest RoD, but exacerbation rates increased with increasing RoD. The highest proportion of patients with ≥ 1 hospitalised exacerbation was in Q4 (Q1 = 19.5% [tiotropium], 26% [control]; Q4 = 33.8% [tiotropium] and 33.1% [control]). Time to first exacerbation and hospitalised exacerbation was shorter with increasing RoD. Rate of decline in SGRQ increased in direct proportion to each quartile. The group with the largest RoD had the highest mortality.Conclusion
Patients can be grouped into different RoD quartiles with the observation of different clinical outcomes indicating that specific (or more aggressive) approaches to management may be needed.Trial Registration
ClinicalTrials.gov number, NCT00144339 相似文献999.
Tanabe F Yone K Kawabata N Sakakima H Matsuda F Ishidou Y Maeda S Abematsu M Komiya S Setoguchi T 《Autophagy》2011,7(12):1462-1471
Intracellular accumulation of altered proteins, including p62 and ubiquitinated proteins, is the basis of most neurodegenerative disorders. The relationship among the accumulation of altered proteins, autophagy, and spinal cord dysfunction by cervical spondylotic myelopathy has not been clarified. We examined the expression of p62 and autophagy markers in the chronically compressed spinal cord of tiptoe-walking Yoshimura mice. In addition, we examined the expression and roles of p62 and autophagy in hypoxic neuronal cells. Western blot analysis showed the accumulation of p62, ubiquitinated proteins, and microtubule-associated protein 1 light chain 3 (LC3), an autophagic marker, in the compressed spinal cord. Immunohistochemical examinations showed that p62 accumulated in neurons, axons, astrocytes, and oligodendrocytes. Electron microscopy showed the expression of autophagy markers, including autolysosomes and autophagic vesicles, in the compressed spinal cord. These findings suggest the presence of p62 and autophagy in the degenerated compressed spinal cord. Hypoxic stress increased the expression of p62, ubiquitinated proteins, and LC3-II in neuronal cells. In addition, LC3 turnover assay and GFP-LC3 cleavage assay showed that hypoxic stress increased autophagy flux in neuronal cells. These findings suggest that hypoxic stress induces accumulation of p62 and autophagy in neuronal cells. The forced expression of p62 decreased the number of neuronal cells under hypoxic stress. These findings suggest that p62 accumulation under hypoxic stress promotes neuronal cell death. Treatment with 3-methyladenine, an autophagy inhibitor decreased the number of neuronal cells, whereas lithium chloride, an autophagy inducer increased the number of cells under hypoxic stress. These findings suggest that autophagy promotes neuronal cell survival under hypoxic stress. Our findings suggest that pharmacological inducers of autophagy may be useful for treating cervical spondylotic myelopathy patients. 相似文献
1000.
Watanabe T Chuma S Yamamoto Y Kuramochi-Miyagawa S Totoki Y Toyoda A Hoki Y Fujiyama A Shibata T Sado T Noce T Nakano T Nakatsuji N Lin H Sasaki H 《Developmental cell》2011,20(3):364-375
MITOPLD is a member of the phospholipase D superfamily proteins conserved among diverse species. Zucchini (Zuc), the Drosophila homolog of MITOPLD, has been implicated in primary biogenesis of Piwi-interacting RNAs (piRNAs). By contrast, MITOPLD has been shown to hydrolyze cardiolipin in the outer membrane of mitochondria to generate phosphatidic acid, which is a signaling molecule. To assess whether the mammalian MITOPLD is involved in piRNA biogenesis, we generated Mitopld mutant mice. The mice display meiotic arrest during spermatogenesis, demethylation and derepression of retrotransposons, and defects in primary piRNA biogenesis. Furthermore, in mutant germ cells, mitochondria and the components of the nuage, a perinuclear structure involved in piRNA biogenesis/function, are mislocalized to regions around the centrosome, suggesting that MITOPLD may be involved in microtubule-dependent localization of mitochondria and these proteins. Our results indicate a conserved role for MITOPLD/Zuc in the piRNA pathway and link mitochondrial membrane metabolism/signaling to small RNA biogenesis. 相似文献