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71.
Kozaki T Kitamura S Higashihara Y Ishibashi K Noguchi H Yasukouchi A 《Journal of PHYSIOLOGICAL ANTHROPOLOGY and Applied Human Science》2005,24(2):183-186
In order to examine whether the spectral compositions of light source may affect sleep quality, sleep architecture under different color temperatures of light sources was evaluated. Seven healthy males were exposed to the light sources of different color temperatures (3000 K, 5000 K and 6700 K) for 6.5 h before sleep. The horizontal illuminance level was kept at 1000 lux. Subjects slept on a bed in near darkness (< 10 lux) after extinguishing the light, and polysomnograms recorded the sleep parameters. In the early phase of the sleep period, the amount of stage-4 sleep (S4-sleep) was significantly attenuated under the higher color temperature of 6700 K compared with the lower color temperature of 3000 K. Present findings suggest that light sources with higher color temperatures may affect sleep quality in a view that S4-sleep period is important for sleep quality. 相似文献
72.
Characterization of UDP-glucose dehydrogenase isoforms in the medicinal legume Glycyrrhiza uralensis
Ayumi Kawasaki Ayaka Chikugo Keita Tamura Hikaru Seki Toshiya Muranaka 《Plant Biotechnology》2021,38(2):205
Uridine 5′-diphosphate (UDP)-glucose dehydrogenase (UGD) produces UDP-glucuronic acid from UDP-glucose as a precursor of plant cell wall polysaccharides. UDP-glucuronic acid is also a sugar donor for the glycosylation of various plant specialized metabolites. Nevertheless, the roles of UGDs in plant specialized metabolism remain poorly understood. Glycyrrhiza species (licorice), which are medicinal legumes, biosynthesize triterpenoid saponins, soyasaponins and glycyrrhizin, commonly glucuronosylated at the C-3 position of the triterpenoid scaffold. Often, several different UGD isoforms are present in plants. To gain insight into potential functional differences among UGD isoforms in triterpenoid saponin biosynthesis in relation to cell wall component biosynthesis, we identified and characterized Glycyrrhiza uralensis UGDs (GuUGDs), which were discovered to comprise five isoforms, four of which (GuUGD1–4) showed UGD activity in vitro. GuUGD1–4 had different biochemical properties, including their affinity for UDP-glucose, catalytic constant, and sensitivity to feedback inhibitors. GuUGD2 had the highest catalytic constant and highest gene expression level among the GuUGDs, suggesting that it is the major isoform contributing to the transition from UDP-glucose to UDP-glucuronic acid in planta. To evaluate the contribution of GuUGD isoforms to saponin biosynthesis, we compared the expression patterns of GuUGDs with those of saponin biosynthetic genes in methyl jasmonate (MeJA)-treated cultured stolons. GuUGD1–4 showed delayed responses to MeJA compared to those of saponin biosynthetic genes, suggesting that MeJA-responsive expression of GuUGDs compensates for the decreased UDP-glucuronic acid pool due to consumption during saponin biosynthesis. 相似文献
73.
Matsuno YK Yamada K Tanabe A Kinoshita M Maruyama SZ Osaka YS Masuko T Kakehi K 《Analytical biochemistry》2007,362(2):245-257
An apparatus, AutoGlycoCutter (AGC), was developed as a tool for rapid release of O-linked-type glycans under alkaline conditions. This system allowed rapid release of oligosaccharides at the glycosaminoglycan-protein linkage region in proteoglycans (PGs). After digestion of PGs with chondroitinase ABC, the oligosaccharides at the linkage region were successfully released from the protein core by AGC within 3 min. The reducing ends of the released oligosaccharides were labeled with 2-aminobenzoic acid and analyzed by a combination of capillary electrophoresis (CE) and matrix-assisted laser desorption time-of-flight mass spectrometry. In addition, the unsaturated disaccharides produced by chondroitinase ABC derived from the outer parts of the glycans were labeled with 2-aminoacridone and analyzed by CE to determine the disaccharide compositions. We evaluated AGC as a method for structural analysis of glycosaminoglycans in some chondroitin-sulfate-type PGs (urinary trypsin inhibitor, bovine nasal cartilage PG, bovine aggrecan, bovine decorin, and bovine biglycan). Recoveries of the released oligosaccharides were 57-73% for all PGs tested in the present study. In particular, we emphasize that the use of AGC achieved ca. 1000-fold rapid release of O-glycans compared with the conventional method. 相似文献
74.
Hironobu Yasui Tatsuya Kawai Shingo Matsumoto Keita Saito Nallathamby Devasahayam James B. Mitchell 《Free radical research》2017,51(9-10):861-871
Hypoxia is considered one of the microenvironmental factors associated with the malignant nature of glioblastoma. Thus, evaluating intratumoural distribution of hypoxia would be useful for therapeutic planning as well as assessment of its effectiveness during the therapy. Electron paramagnetic resonance imaging (EPRI) is an imaging technique which can generate quantitative maps of oxygen in vivo using the exogenous paramagnetic compound, triarylmethyl and monitoring its line broadening caused by oxygen. In this study, the feasibility of EPRI for assessment of oxygen distribution in the glioblastoma using orthotopic U87 and U251 xenograft model is examined. Heterogeneous distribution of pO2 between 0 and 50?mmHg was observed throughout the tumours except for the normal brain tissue. U251 glioblastoma was more likely to exhibit hypoxia than U87 for comparable tumour size (median pO2; 29.7 and 18.2?mmHg, p?=?.028, in U87 and U251, respectively). The area with pO2 under 10?mmHg on the EPR oximetry (HF10) showed a good correlation with pimonidazole staining among tumours with evaluated size. In subcutaneous xenograft model, irradiation was relatively less effective for U251 compared with U87. In conclusion, EPRI is a feasible method to evaluate oxygen distribution in the brain tumour. 相似文献
75.
Modelling and predicting the potential habitat and future range expansion of invasive species can help managers to mitigate
the impact of such species. Because habitat suitability and the colonization process are key determinants of range expansion,
inferences drawn from invasion patterns should be based on both attributes. To predict the potential habitat and expansion
rate of the invasive tree Bischofia javanica on Hahajima Island, we used simultaneous models of habitat and dispersal to estimate the effect of environment and dispersal
from the source population on the current distribution. We compared the fit and the estimated magnitudes of the environment
and dispersal effects in the simultaneous models with those in habitat suitability and colonization kernel models. The values
of Akaike’s information criterion for the simultaneous models were better than those of the habitat suitability and colonization
kernel models, indicating that the current distribution of Bischofia was determined by both environment and dispersal. The simultaneous models predicted that the potential habitat of Bischofia would be larger than that predicted by the habitat suitability model. The potential habitat distribution and future invasion
predicted by the simultaneous models will contribute to the development of specific landscape-scale management plans to control
this invasive species. 相似文献
76.
Babacar Diao Papa Ahmed Fall Ibrahima Bah Cyrille Ze Ondo Yoro Diallo Lamine Niang Alain Khassim Ndoye Sérigne Maguèye Gueye Mamadou Ba Bay Assane Diagne 《Andrologie》2006,16(2):131-134
Patients and Methods
This is a retrospective study of patients admitted with gunshot injuries to the external genital organs to the urology departments of Aristide Le Dantec Hospital, Grand Yoff General Hospital and Dakar Principal Hospital, between January 1998 and January 2003. The following parameters were studied: patients’ age and gender, interval between accident and admission, clinical features, complementary investigations and treatment, and early and late outcomes.Results
Only males were observed and the mean age of these patients was 37.7 years (range: 22–52 years). Lesions were accidental in five cases. Two cases of testicular wounds, two cases of corpus cavernosum injuries, two cases of urethral injury, and one case of perineal wound were observed. After excision of the lesions, complementary procedures consisted of: orchidectomy in two cases, corpus cavernosum — albuginea suture in two cases and end-to-end urethral suture in one case. Perineoscrotal wounds were sutured three days after debridement. All patients received antibiotics and antitetanus serum. No death was observed during the immediate follow-up. No case of urethral stricture or erectile dysfunction was observed with a follow-up of 18 months. Semen analysis was normal in the two cases of orchidectomy. 相似文献77.
Screening of faecal bacteria for glycyrrhetic acid (GA) production by hydrolysing of glycyrrhizin (GL) resulted in the isolation of two strains, designated ZM35T and ZM38. Strains ZM35T and ZM38 were Gram-positive, obligate anaerobic, non-spore-forming and rod-shaped bacteria. Analysis of the 16S rRNA gene sequences indicated that strains ZM35T and ZM38 belonged to cluster XIVa of the genus Clostridium. The 16S rRNA gene sequences of strains ZM35T and ZM38 were identical. Strain ZM35T exhibited approximately 94% to 95% identity with the validly described species, Clostridium oroticum(94.5%), Eubacterium contortum(93.8%), Ruminococcus gnavus(94.5%) and R. torques(95.1%). In an experiment of DNA-DNA hybridization, it was confirmed that strains ZM35T and ZM38 were the same species. The guanine-plus-cytosine (G+C) content of strain ZM35T is 45.7 mol%. Based on the phylogenetic and phenotypic findings, we propose that strains ZM35T and ZM38 be assigned to a novel species named Clostridium glycyrrhizinilyticum. The type strain is ZM35T (=JCM 13368T=DSM 17593T). 相似文献
78.
Huang M Ida H Arima K Nakamura H Aramaki T Fujikawa K Tamai M Kamachi M Kawakami A Yamasaki H Origuchi T Eguchi K 《Life sciences》2007,81(19-20):1461-1466
Our recent report demonstrated that apoptosis-specific autoantibodies against granzyme B-induced cleavage fragments of SS-B (La) were found in the sera from patients with primary Sj?gren's syndrome. The objective of this study was identified by the intracellular redistribution of La autoantigen during granzyme B-induced apoptosis. We developed green fluorescence protein (GFP)-La and GFP-LaDelta220 (generation of granzyme B-specific cleavage of La protein) fusion proteins. GFP-La protein was localized in the nucleus, whereas the GFP-LaDelta220 protein predominantly existed in the cytoplasm in transformed A293T cells. Nuclear GFP-La protein was translocated to cytoplasm after granzyme B enriched YT cells incubation. La protein in human salivary grand HSG cells is cleaved and translocated from the nucleus to the cytoplasm after YT cell co-cultivation. These results suggest that La protein is cleaved by granzyme B and N-terminal La fragment (27 kD) translocated to the cytoplasm, thus leading to a novel autoantibody production during granzyme B-mediated cytotoxicity. 相似文献
79.
Woclawek-Potocka I Bah MM Korzekwa A Piskula MK Wiczkowski W Depta A Skarzynski DJ 《Experimental biology and medicine (Maywood, N.J.)》2005,230(3):189-199
Phytoestrogens acting as endocrine disruptors may induce various pathologies in the female reproductive tract. The purpose of this study was to determine whether phytoestrogens present in the soybean and/or their metabolites are detectable in the plasma of cows fed a diet rich in soy and whether these phytoestrogens influence reproductive efficiency and prostaglandin (PG) synthesis during the estrous cycle and early pregnancy in the bovine endometrium. In in vivo Experiment 1, we found significant levels of daidzein and genistein in the fodder and their metabolites (equol and p-ethyl-phenol) in bovine serum and urine. The mean number of artificial inseminations (AIs) and pregnancy rates in two kinds of herds, control and experimental (cows fed with soybean 2.5 kg/day), were almost double in the soy-diet herd in comparison with the control animals. In in vivo Experiment 2, three out of five heifers fed soybean (2.5 kg/day) became pregnant whereas four out of five heifers in the control group became pregnant. The concentrations of a metabolite of PGF2alpha (PGFM) were significantly higher in the blood plasma of heifers fed a diet rich in soybean than those in the control heifers throughout the first 21 days after ovulation and AI. The higher levels of PGFM were positively correlated with equol and p-ethyl phenol concentrations in the blood. In in vitro experiments, the influence of isoflavones on PG secretion in different stages of the estrous cycle was studied. Although all phytoestrogens augmented the output of both PGs throughout the estrous cycle, equol and p-ethyl-phenol preferentially stimulated PGF2alpha output. The results obtained lead to the conclusion that soy-derived phytoestrogens and their metabolites disrupt reproductive efficiency and uterus function by modulating the ratio of PGF2alpha to PGE2, which leads to high, nonphysiological production of luteolytic PGF2alpha in cattle during the estrous cycle and early pregnancy. 相似文献
80.
Nobukatsu Horita Kiichiro Tsuchiya Ryohei Hayashi Keita Fukushima Shuji Hibiya Masayoshi Fukuda Yoshihito Kano Tomohiro Mizutani Yasuhiro Nemoto Shiro Yui Ryuichi Okamoto Tetsuya Nakamura Mamoru Watanabe 《Biochemical and biophysical research communications》2014