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81.
Nishi Y Fujimoto S Sasaki M Mukai E Sato H Sato Y Tahara Y Nakamura Y Inagaki N 《The Biochemical journal》2011,435(2):421-430
In pancreatic β-cells, glucose-induced mitochondrial ATP production plays an important role in insulin secretion. The mitochondrial phosphate carrier PiC is a member of the SLC25 (solute carrier family 25) family and transports Pi from the cytosol into the mitochondrial matrix. Since intramitochondrial Pi is an essential substrate for mitochondrial ATP production by complex V (ATP synthase) and affects the activity of the respiratory chain, Pi transport via PiC may be a rate-limiting step for ATP production. We evaluated the role of PiC in metabolism-secretion coupling in pancreatic β-cells using INS-1 cells manipulated to reduce PiC expression by siRNA (small interfering RNA). Consequent reduction of the PiC protein level decreased glucose (10 mM)-stimulated insulin secretion, the ATP:ADP ratio in the presence of 10 mM glucose and elevation of intracellular calcium concentration in response to 10 mM glucose without affecting the mitochondrial membrane potential (Δψm) in INS-1 cells. In experiments using the mitochondrial fraction of INS-1 cells in the presence of 1 mM succinate, PiC down-regulation decreased ATP production at various Pi concentrations ranging from 0.001 to 10 mM, but did not affect Δψm at 3 mM Pi. In conclusion, the Pi supply to mitochondria via PiC plays a critical role in ATP production and metabolism-secretion coupling in INS-1 cells. 相似文献
82.
Yageta Y Ishii Y Morishima Y Masuko H Ano S Yamadori T Itoh K Takeuchi K Yamamoto M Hizawa N 《Journal of virology》2011,85(10):4679-4690
Influenza virus is a common respiratory tract viral infection. Although influenza can be fatal in patients with chronic pulmonary diseases such as chronic obstructive pulmonary disease, its pathogenesis is not fully understood. The Nrf2-mediated antioxidant system is essential to protect the lungs from oxidative injury and inflammation. In the present study, we investigated the role of Nrf2 in protection against influenza virus-induced pulmonary inflammation after cigarette smoke exposure with both in vitro and in vivo approaches. For in vitro analyses, peritoneal macrophages isolated from wild-type and Nrf2-deficient mice were treated with poly(I:C) and/or cigarette smoke extract. For in vivo analysis, these mice were infected with influenza A virus with or without exposure to cigarette smoke. In Nrf2-deficient macrophages, NF-κB activation and the induction of its target inflammatory genes were enhanced after costimulation with cigarette smoke extract and poly(I:C) compared with wild-type macrophages. The induction of antioxidant genes was observed for the lungs of wild-type mice but not those of Nrf2-deficient mice after cigarette smoke exposure. Cigarette smoke-exposed Nrf2-deficient mice showed higher rates of mortality than did wild-type mice after influenza virus infection, with enhanced peribronchial inflammation, lung permeability damage, and mucus hypersecretion. Lung oxidant levels and NF-κB-mediated inflammatory gene expression in the lungs were also enhanced in Nrf2-deficient mice. Our data indicate that the antioxidant pathway controlled by Nrf2 is pivotal for protection against the development of influenza virus-induced pulmonary inflammation and injury under oxidative conditions. 相似文献
83.
Shuichi Miyagawa Yusaku Koyama Mika Kokubo Yuichi Matsushita Yoshinao Adachi Sengdeaune Sivilay Nobumitsu Kawakubo Shinya Oba 《Journal of ethnobiology and ethnomedicine》2011,7(1):1-6
Background
This study was conducted to identify medicinal plants and spices used for medicine by the community of Beni-Sueif, Upper Egypt.Methods
Ethnobotanical data from local people was collected using direct interviews and a semi-structured questionnaire.Results
Forty-eight plant species belonging to twenty-seven families and forty-seven genera were encountered during the study. Their botanical and vernacular names, plant parts used and medicinal uses are given. Results of the study were analyzed using two quantitative tools. The factor informant consensus indicated the agreement in the use of plants and the fidelity level indicated the ratio between the number of informants who independently suggested the use of a species for the same major purpose and the total number of informants who mentioned the plant for any use. The results of the factor informant consensus showed that the cardiovascular category has the greatest agreement, followed by the immunological, gastrointestinal and respiratory categories. The most important species according to their fidelity are: Hibiscus sabdariffa L. for the cardiovascular category; Trigonella foenum-graecum L. for the immunological category; Mentha piperita L. for the gastrointestinal category and Pimpinella anisum L. for the respiratory category.Conclusions
Medicinal plants are still used for treatment in Beni-Sueif community despite the availability of prescribed medications. Documentation of this ethnomedicinal knowledge is important. Evaluation of pharmacological activity for the promising medicinal plants is suggested. 相似文献84.
Role of G protein‐coupled receptor kinase 2 in oxidative and nitrosative stress‐related neurohistopathological changes in a mouse model of sepsis‐associated encephalopathy 下载免费PDF全文
85.
Hirotaka Sumi Yuichi Ishikawa Kazunari Nagaoka Hideshige Toda Yoshio Aikawa 《Soil & Sediment Contamination》2014,23(8):899-916
We investigated the effect of adding an alkaline material (containing calcium carbonate and gypsum) on the immobilization of heavy metals (Cd, Cu, Pb, and Zn) in a paddy soil slightly contaminated with Cd and Zn under flooded and non-flooded conditions in the laboratory. Adding the alkaline material increased the soil pH and significantly decreased the exchangeable fraction of all of the metals, especially for Cd (>75% decrease) and Zn (ca. 90% decrease), under both flooded and non-flooded conditions. Drying the flooded soil samples increased the ratio of exchangeable fraction to the total fraction, particularly for Cd. The exchangeable fraction ratio was lower in the dried, previously flooded samples that contained the alkaline material than in the samples that did not contain the alkaline material, indicating that adding the alkaline material would be an effective way of immobilizing heavy metals during the oxidation of anoxic soils. These results show that the alkaline material can be used to immobilize heavy metals under both anoxic and oxic conditions, and that the effects of flooding and amending a paddy soil with alkaline material on the chemical forms will be different between heavy metals. 相似文献
86.
Masaya Yamaoka Norikazu Maeda Yasunori Takayama Ryohei Sekimoto Yu Tsushima Keisuke Matsuda Takuya Mori Kana Inoue Hitoshi Nishizawa Makoto Tominaga Tohru Funahashi Iichiro Shimomura 《PloS one》2014,9(11)
Visceral fat adiposity plays an important role in the development of metabolic syndrome. We reported previously the impact of human visceral fat adiposity on gene expression profile of peripheral blood cells. Genes related to circadian rhythm were highly associated with visceral fat area and period homolog 1 (PER1) showed the most significant negative correlation with visceral fat area. However, regulation of adipose Per1 remains poorly understood. The present study was designed to understand the regulation of Per1 in adipose tissues. Adipose Per1 mRNA levels of ob/ob mice were markedly low at 25 and 35 weeks of age. The levels of other core clock genes of white adipose tissues were also low in ob/ob mice at 25 and 35 weeks of age. Per1 mRNA was mainly expressed in the mature adipocyte fraction (MAF) and it was significantly low in MAF of ob/ob mice. To examine the possible mechanisms, 3T3-L1 adipocytes were treated with H2O2, tumor necrosis factor-α (TNF-α), S100A8, and lipopolysaccharide (LPS). However, no significant changes in Per1 mRNA level were observed by these agents. Exposure of cultured 3T3-L1 adipocytes to low temperature (33°C) decreased Per1 and catalase, and increased monocyte chemoattractant protein-1 (Mcp-1) mRNA levels. Hypothermia also worsened insulin-mediated Akt phosphorylation in 3T3-L1 adipocytes. Finally, telemetric analysis showed low temperature of adipose tissues in ob/ob mice. In obesity, adipose hypothermia seems to accelerate adipocyte dysfunction. 相似文献
87.
Hayuki Sugimoto Yuichi Nakajima Ayaka Motoyama Erina Katagiri Takeshi Watanabe Kazushi Suzuki 《Biopolymers》2020,111(1):e23339
Chitin-binding protein 21 (CBP21) from Serratia marcescens is a lytic polysaccharide monooxygenase that contains a copper ion as a cofactor. We aimed to elucidate the unfolding mechanism of CBP21 and the effects of Cu2+ on its structural stability at pH 5.0. Thermal unfolding of both apo- and holoCBP21 was reversible. ApoCBP21 unfolded in a simple two-state transition manner. The peak temperature of the DSC curve, tp, for holoCBP21 (74.4°C) was about nine degrees higher than that for apoCBP21 (65.6°C). The value of tp in the presence of excess Cu2+ was around 75°C, indicating that Cu2+ does not dissociate from the protein molecule during unfolding. The unfolding mechanism of holoCBP21 was considered to be as follows: N∙Cu2+ ⇌ U∙Cu2+, where N and U represent the native and unfolded states, respectively. Urea-induced equilibrium unfolding analysis showed that holoCBP21 was stabilized by 35 kJ mol−1 in terms of the Gibbs energy change for unfolding (pH 5.0, 25°C), compared with apoCBP21. The increased stability of holoCBP21 was considered to result from the structural stabilization of the protein-Cu2+ complex itself. 相似文献
88.
Ken Nozawa Takayoshi Shotake Yoshi Kawamoto Yuichi Tanabe 《Primates; journal of primatology》1982,23(3):432-443
Amount of genetic differentiation between chimpanzee and man was estimated from the result of comparative electrophoretic
screening of blood protein variations at 32 independent genetic loci. TheNei's genetic distance (D) was calculated as 0.4514, and from this value the divergence time between the two species was estimated as 2.26 million
years; considering the variation among amino-acid substitution rate in different proteins, the corrected figures were given
as genetic distance of 0.5706 and divergence time of 2.85 million years. This genetic difference is considered too small the
two species to be allocated in different families, in accordance with the results of the similar kind of analyses byKing andWilson (1975) and Bruce andAyala (1979). Discussions were made for a discrepancy between the divergence times estimated by using and not by using the splitting
time recognized by paleoprimatologists as a reference, and for the difference in the estimations made in different laboratories. 相似文献
89.
Inhibition of RANKL‐dependent cellular fusion in pre‐osteoclasts by amiloride and a NHE10‐specific monoclonal antibody 下载免费PDF全文
90.
Takeichiro Aso Mioko Matsuo Hideyuki Kiyohara Kenichi Taguchi Fumihide Rikimaru Mototsugu Shimokawa Yuichi Segawa Yuichiro Higaki Hirohito Umeno Tadashi Nakashima Muneyuki Masuda 《PloS one》2015,10(3)