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排序方式: 共有1565条查询结果,搜索用时 46 毫秒
61.
Katayama Kazuhiro Hosui Atsushi Sakai Yoshiyuki Itou Minoru Matsuzaki Yasushi Takamori Yoriyuki Hosho Keiko Tsuru Tomomi Takikawa Yasuhiro Michitaka Kojiro Ogawa Eishin Miyoshi Yoko Ito Toshifumi Ida Shinobu Hamada Izumi Miyoshi Katsunori Kodama Hiroko Takehara Tetsuo 《Biological trace element research》2020,195(1):71-81
Biological Trace Element Research - The essential trace element zinc maintains liver functions. Liver diseases can alter overall zinc concentrations, and hypozincemia is associated with various... 相似文献
62.
Stefenon Valdir Marcos Ree Joseph Francis Pinheiro Marcos Vinicius Marques Goeten Daniela Steiner Neusa Guerra Miguel Pedro 《Plant Cell, Tissue and Organ Culture》2020,142(2):241-251
Plant Cell, Tissue and Organ Culture (PCTOC) - Mambalgin-1 is a peptide that acts as a potent analgesic through inhibiting acid-sensing ion channels (ASIC) in nerve cells. Research has shown that... 相似文献
63.
64.
Nathalia Torres Dutra Vanildo Silveira Inga Gonçalves de Azevedo Lupis Ribeiro Gomes‐Neto Arnoldo Rocha Façanha Neusa Steiner Miguel Pedro Guerra Eny Iochevet Segal Floh Claudete Santa‐Catarina 《Physiologia plantarum》2013,148(1):121-132
Polyamines (PAs) are abundant polycationic compounds involved in many physiological processes in plants, including somatic embryogenesis. This study investigates the role of PAs on cellular growth and structure of pro‐embryogenic masses (PEMs), endogenous PA and proton pump activities in embryogenic suspension cultures of Araucaria angustifolia. The embryogenic suspension cultures were incubated with putrescine (Put), spermidine (Spd), spermine (Spm) and the inhibitor methylglyoxal‐bis(guanylhydrazone) (MGBG), respectively (1 mM). After 24 h and 21 days, the cellular growth and structure of PEMs, endogenous PA contents and proton pump activities were analyzed. The addition of Spm reduced the cellular growth and promoted the development of PEMs in embryogenic cultures, which could be associated with a reduction in the activities of proton pumps, such as H+‐ATPase P‐ and V‐types and H+‐PPases, and alterations in the endogenous PA contents. Spm significantly affected the physiology of the A. angustifolia somatic embryogenesis suspension, as it potentially affects cellular growth and structure of PEMs through the modulation of proton pump activities. This work demonstrates the involvement of exogenous PAs in the modulation of cellular growth and structure of PEMs, endogenous PA levels and proton pump activities during somatic embryogenesis. To our knowledge, this study is the first to report a relationship between PAs and proton pump activities in these processes. The results obtained in this study offer new perspectives for studies addressing the role of PAs and proton pump on somatic embryogenesis in this species. 相似文献
65.
Rumiko Nakashita Yuzuru Hamada Eishi Hirasaki Juri Suzuki Toru Oi 《Primates; journal of primatology》2013,54(3):271-281
We determined the magnitude of isotopic fractionation of carbon and nitrogen stable isotope ratios (as enrichment factors, Δδ13C and Δδ15N, respectively) between the tissues and diets of captive Japanese macaques (Macaca fuscata) using a controlled feeding experiment, to provide basic data for reconstructing their feeding habits. The Δδ13C and Δδ15N values, respectively, were 0.9 ± 0.2 ‰ (mean ± standard deviation, SD) and 3.0 ± 0.3 ‰ for whole blood, 1.3 ± 0.2 ‰ and 4.3 ± 0.3 ‰ for plasma, and 0.8 ± 0.2 ‰ and 3.0 ± 0.2 ‰ for red blood cells. However, the Δδ13C and Δδ15N values for hair were 2.8 ± 0.3 ‰ and 3.4 ± 0.2 ‰, respectively. No difference was detected in the δ13C and δ15N values of hair sampled from different parts of the body. We investigated the effects of diet on δ13C in growing hair by alternating the diet of the macaques each month between two diets that differed markedly in δ13C. Hair regrown after shaving repeatedly recorded the δ13C of the diet consumed during the time of hair growth. On the other hand, hair naturally grown during the diet-change experiment did not show a clear pattern. One possible reason is that the hair had grown abnormally under unnatural indoor conditions and showed complicated isotope signatures. To reconstruct the long-term feeding history of Japanese macaques, we need to further clarify the relationships between the stable isotope signature of diet and various body tissues. 相似文献
66.
Shin Hamada Kennichi Satoh Shin Miura Morihisa Hirota Atsushi Kanno Atsushi Masamune Kazuhiro Kikuta Kiyoshi Kume Jun Unno Shinichi Egawa Fuyuhiko Motoi Michiaki Unno Tooru Shimosegawa 《Journal of cellular physiology》2013,228(6):1255-1263
Invasive ductal adenocarcinoma (IDA) of the pancreas manifests poor prognosis due to the early invasion and distant metastasis. In contrast, intraductal papillary mucinous adenoma or carcinoma (IPMA or IPMC) reveals better clinical outcomes. Various molecular mechanisms contribute to these differences but entire picture is still unclear. Recent researches emphasized the important role of miRNA in biological processes including cancer invasion and metastasis. We previously described that miR‐126 is down‐regulated in IDA compared with IPMA or IPMC, and miR‐126 regulates the expression of invasion related molecule disintegrin and metalloproteinase domain‐containing protein 9 (ADAM9). Assessing the difference of miRNA expression profiles of IDA, IPMA, and IPMC, we newly identified miR‐197 as an up‐regulated miRNA specifically in IDA. Expression of miR‐197 in pancreatic cancer cells resulted in the induction of epithelial–mesenchymal transition (EMT) along with the down‐regulation of p120 catenin which is a putative target of miR‐197. Direct interaction between miR‐197 and p120 catenin mRNA sequence was confirmed by 3′UTR assay, and knockdown of p120 catenin recapitulated EMT induction in pancreatic cancer cells. In situ hybridization of miR‐197 and immunohistochemistry of p120 catenin showed mutually exclusive patterns suggesting pivotal role of miR‐197 in the regulation of p120 catenin. This miR‐197/p120 catenin axis could be a novel therapeutic target. J. Cell. Physiol. 228: 1255–1263, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
67.
Alexander R. Mackie Prasanna Krishnamurthy Suresh K. Verma Tina Thorne Veronica Ramirez Gangjian Qin Tatiana Abramova Hiromichi Hamada Douglas W. Losordo Raj Kishore 《The Journal of biological chemistry》2013,288(25):18022-18034
We have shown previously that estrogen (estradiol, E2) supplementation enhances voluntary alcohol consumption in ovariectomized female rodents and that increased alcohol consumption impairs ischemic hind limb vascular repair. However, the effect of E2-induced alcohol consumption on post-infarct myocardial repair and on the phenotypic/functional properties of endothelial progenitor cells (EPCs) is not known. Additionally, the molecular signaling of alcohol-estrogen interactions remains to be elucidated. This study examined the effect of E2-induced increases in ethanol consumption on post-infarct myocardial function/repair. Ovariectomized female mice, implanted with 17β-E2 or placebo pellets were given access to alcohol for 6 weeks and subjected to acute myocardial infarction. Left ventricular functions were consistently depressed in mice consuming ethanol compared with those receiving only E2. Alcohol-consuming mice also displayed significantly increased infarct size and reduced capillary density. Ethanol consumption also reduced E2-induced mobilization and homing of EPCs to injured myocardium compared with the E2-alone group. In vitro, exposure of EPCs to ethanol suppressed E2-induced proliferation, survival, and migration and markedly altered E2-induced estrogen receptor-dependent cell survival signaling and gene expression. Furthermore, ethanol-mediated suppression of EPC biology was endothelial nitric oxide synthase-dependent because endothelial nitric oxide synthase-null mice displayed an exaggerated response to post-acute myocardial infarction left ventricular functions. These data suggest that E2 modulation of alcohol consumption, and the ensuing EPC dysfunction, may negatively compete with the beneficial effects of estrogen on post-infarct myocardial repair. 相似文献
68.
Huong T.T. Phan Takahiro HataMasamune Morita Tsuyoshi YodaTsutomu Hamada Mun'delanji C. VestergaardMasahiro Takagi 《生物化学与生物物理学报:生物膜》2013
The interaction of amyloid beta (Aβ) peptide with cell membranes has been shown to be influenced by Aβ conformation, membrane physicochemical properties and lipid composition. However, the effect of cholesterol and its oxidized derivatives, oxysterols, on Aβ-induced neurotoxicity to membranes is not fully understood. We employed here model membranes to investigate the localization of Aβ in membranes and the peptide-induced membrane dynamics in the presence of cholesterol and 7-ketocholesterol (7keto) or 25-hydroxycholesterol (25OH). Our results have indicated that oxysterols rendered membranes more sensitive to Aβ, in contrast to role of cholesterol in inhibiting Aβ/membrane interaction. We have demonstrated that two oxysterols had different impacts owing to distinct positions of the additional oxygen group in their structures. 7keto-containing cell-sized liposomes exhibited a high propensity toward association with Aβ, while 25OH systems were more capable of morphological changes in response to the peptide. Furthermore, we have shown that 42-amino acid Aβ (Aβ-42) pre-fibril species had higher association with membranes, and caused membrane fluctuation faster than 40-residue isoform (Aβ-40). These findings suggest the enhancing effect of oxysterols on interaction of Aβ with membranes and contribute to clarify the harmful impact of cholesterol on Aβ-induced neurotoxicity by means of its oxidation. 相似文献
69.
Neusa Martins Maria Leonor Osório Sandra Gonçalves Júlio Osório Anabela Romano 《Biometals》2013,26(3):427-437
We evaluated the impact of low pH and aluminum (Al) on the leaves and roots of Plantago almogravensis Franco and Plantago algarbiensis Samp., focusing on energy partitioning in photosystem II, H2O2 levels, lipid peroxidation, electrolyte leakage (EL), protein oxidation, total soluble protein content and antioxidant enzyme activities. In both species, Al triggered more changes in oxidative metabolism than low pH alone, particularly in the roots. We found that Al increased the levels of H2O2 in P. algarbiensis roots, but reduced the levels of H2O2 in P. almogravensis leaves and roots. Neither low pH nor Al affected the spatial heterogeneity of chlorophyll fluorescence, the maximum photochemical efficiency of PSII (Fv/Fm), the actual quantum efficiency of PSII (?PSII) or the quantum yields of regulated (?NPQ) and nonregulated (?NO) energy dissipation, and there was no significant change in total soluble protein content and EL. In P. algarbiensis, Al increased the carbonyl content and the activities of superoxide dismutase (SOD) and catalase (CAT) in the roots, and also CAT, ascorbate peroxidase and guaiacol peroxidase activities in the leaves. In P. almogravensis, Al reduced the level of malondialdehyde in the roots as well as SOD activity in the leaves and roots. We found that P. almogravensis plantlets could manage the oxidative stress caused by low pH and Al, whereas the P. algarbiensis antioxidant system was unable to suppress Al toxicity completely, leading to the accumulation of H2O2 and consequential protein oxidation in the roots. 相似文献
70.
Yuji Enomoto Yoshio Furutani Hiroshi Naganawa Masa Hamada Tomio Takeuchi Hamao Umezawa 《Bioscience, biotechnology, and biochemistry》2013,77(7):1331-1336
In the screening for inhibitors of cyclic adenosine-3′,5′-monophosphate phosphodiesterase, two compounds, PDE-I (C13H13N3O5) and PDE-II (C14H14N2O5), were isolated from culture filtrates of a Streptomyces. Concentrations for 50% inhibitions of PDE-I and PDE-II against the high Km enzyme were 15 µm and 13 µm, and those against the low Km enzyme were 65 µm and 130 µm, respectively. Production, isolation and characterization of these compounds are described. 相似文献