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81.
82.
Wada R Sakata I Kaiya H Nakamura K Hayashi Y Kangawa K Sakai T 《Regulatory peptides》2003,111(1-3):123-128
Ghrelin was isolated from the rat stomach as an endogenous ligand for the growth hormone secretagogue receptor (GHS-R) and has been found in the gastrointestinal tract of many vertebrates. Although the sequence and structure of chicken ghrelin has recently been determined, morphological characteristics of ghrelin cells in the chicken gastrointestinal tract are still obscure. In this study, we investigated ghrelin expression and distribution of ghrelin-producing cells in the hatching and adult chicken gastrointestinal tract by RT-PCR, immunohistochemistry and in situ hybridization. Ghrelin mRNA expression was observed mainly in the proventriculus in the hatching chicken and in the proventriculus, pylorus and duodenum of the adult chicken by RT-PCR. Ghrelin-immunopositive (ghrelin-ip) cells in the proventriculus were located at the mucosal layer but not in the myenteric plexus or smooth muscle layer. The number of ghrelin-ip cells in the adult chicken was greater than that in the hatching chicken. Interestingly, in the adult chicken, the number of ghrelin-ip cells were almost the same as that of ghrelin mRNA-expressing (ghrelin-ex) cells; however, in the hatching chicken, the number of ghrelin-ex cells was greater than that of ghrelin-ip cells. These results clearly demonstrate that ghrelin-producing cells exist in the chicken gastrointestinal tract, especially in the proventriculus, from hatching to adult stages of development, as well as in mammals. 相似文献
83.
Watanabe T Hashimoto Y Umemoto Y Tatebe D Furuta E Fukamizo T Yamamoto K Utsumi R 《Journal of molecular microbiology and biotechnology》2003,6(3-4):155-163
The response regulator YycF is essential for cell growth in gram-positive bacteria including Bacillus subtilis, Staphylococcus aureus and Streptococcus pneumoniae. To study the function of YycF in the essential process, we characterized a YycF (H215P) mutation that caused temperature-sensitive growth in B. subtilis. The response regulators YycF and YycF (H215P) were analyzed using circular dichroism spectroscopy, whose T(m) values were 56.0 and 45.9 degrees C, respectively, suggesting that YycF (H215P) significantly affects the protein structure with an increase in temperature. Furthermore, using the gel mobility shift assay and DNase I footprinting, we investigated the effect of YycF (H215P) on binding to the YycF box of ftsAZ operon of B. subtilis. The replacement of the histidine 215 with proline resulted in a decrease of the DNA-binding ability of YycF in vitro. In vivo, using Escherichia coli two-hybrid and homodimerization assays, we clarified that His 215 of YycF plays a crucial role in the homodimerization of the protein. Thus the essential genes involved in growth of B. subtilis appear to be regulated by the homodimer of YycF. These results suggest that the YycF dimerization is an excellent target for the discovery of novel antibiotics. 相似文献
84.
OBJECTIVE: Gynecomastia is known to be a side effect of neuroleptics. The authors investigated the prevalence of gynecomastia and galactorrhea in a group of regularly neuroleptic-treated male patients. METHODS: Gynecomastia was defined as a palpable, discrete button of firm subareolar tissue measuring at least 2 cm in diameter. The subjects were 100 male patients who were taking neuroleptic treatment regularly. Each patient gave informed consent for the research involved in this study. RESULTS: (1) Palpable gynecomastia was present in 2% of the patient group, but not at all in the normal group. (2) Galactorrhea was not present in either patient or normal group. (3) The mean level of the serum prolactin in the group of patients without gynecomastia (n = 53) was significantly higher than that in the normal group (n = 35), but there was no significant difference in blood luteinizing hormone, follicle-stimulating hormone, testosterone (T), estradiol (E(2)) or T/E(2) ratio between the groups. (4) The mean level of the T/E(2) ratio in the patients with gynecomastia tended to be higher than that in the group of patients without gynecomastia. CONCLUSIONS: Overall, these results seem to indicate that (i) gynecomastia is not common in the Japanese population, and (ii) in male patients neither palpable gynecomastia nor galactorrhea is a common side effect of neuroleptics. To clarify the relation between gynecomastia and neuroleptic treatment, large prospective studies are required. 相似文献
85.
Yamamoto Y Kusakabe T Hayashida Y Yoshida T Matsuda H Atoji Y Suzuki Y 《Histochemistry and cell biology》2000,114(4):277-282
The morphology, topographic distribution, effects of denervation, and exposure to hypercapnic hypoxia of endocrine cells were examined in rat larynx. The endocrine cells, which were immunoreactive for protein gene product 9.5 (PGP 9.5) and calcitonin gene-related peptide (CGRP), were observed within the epithelial layer of the laryngeal cavity and in the laryngeal gland, while solitary endocrine cells with apical and/or basal cytoplasmic processes appeared near the glottis. After denervation of the left cervical vagosympathetic trunk and the superior laryngeal nerve, the number of mucosal endocrine cells in the denervated side was not significantly different from that in the intact side. After exposure to hypercapnic hypoxia for 3 months, the number of endocrine cells with PGP 9.5 and CGRP was markedly increased. In conclusion, the secretion of laryngeal endocrine cells may be stimulated by CO2 rather than O2. Furthermore, the endocrine cells and the sensory and autonomic nervous system may regulate each other by an axon reflex mechanism. Endocrine cells appear to play a very important role in the local regulation of the laryngeal mucosa. 相似文献
86.
Phenotypic Characterization of Polysaccharidases Produced by Four Prevotella Type Strains 总被引:3,自引:0,他引:3
Matsui H Ogata K Tajima K Nakamura M Nagamine T Aminov RI Benno Y 《Current microbiology》2000,41(1):45-49
Four ruminal Prevotella type strains, P. ruminicola JCM8958T, P. bryantii B14T, P. albensis M384T, and P. brevis ATCC19188T, were characterized for polysaccharide-degrading activities with the reducing sugar release assay and zymogram analyses.
Carboxymethylcellulase, xylanase, and polygalacturonate (PG)-degrading enzyme activities were determined in cultures grown
on oat spelt xylan, xylose, arabinose, cellobiose, and glucose as sole growth substrates. P. ruminicola and P. albensis showed carboxymethylcellulase induction patterns. When xylan was supplied as a sole growth substrate, xylanase activities
produced by P. bryantii and P. albensis were at least 18- and 11-fold higher, respectively, than during growth on other carbohydrates, suggesting that the regulation
of the xylanases was highly specific to xylan. All strains constitutively produced PG-degrading enzymes. The corresponding
activity of P. bryantii was more than 40-fold higher than in other strains. Zymogram analyses routinely detected the presence of high-molecular-weight
(100–170 kDa) polysaccharide-degrading enzymes in ruminal Prevotella. Characteristics of the polysaccharide-degrading activities showed diversity of ruminal Prevotella species.
Received: 29 November 1999 / Accepted: 1 February 2000 相似文献
87.
Nagamine I Shimada J Nakamura Y Toyoda A Minato H 《The Journal of General and Applied Microbiology》1998,44(6):375-380
The features and the constitution of the microbial population of fresh feces were compared between pigs fed a diet supplemented with dietary microbes and pigs given nonsupplemented diets. The former were reared on farm C and the latter on farms A and B. The concentrations of ammonia-N, indole, and skatole of fresh feces were not significantly different between pigs reared on farm C and those raised on farms A and B, but the concentrations of ammonia-N and the skatole of fresh feces were significantly different between pigs reared on farms A and B. The total VFA (volatile fatty acids) concentration of fresh feces in pigs on farm C was slightly lower than in those on farms A and B. Moreover, the molar proportion of the acetic acid in feces in pigs on farm C was lower; inversely, that of propionic and butyric acids was higher in comparison with those on farms A and B. No differences were evident in the total viable counts of feces among pigs reared on the three different farms. Clostridium perfringens was abundant in feces of pigs raised on farms A and B, but it was not detected in pigs reared on farm C. Megasphaerae, bifidobacteria, and clostridia except for C. perfringens were more abundant in the feces of pigs fed a diet supplemented with dietary microbes on farm C, compared with pigs given the nonsupplemented diets on farms A and B. 相似文献
88.
Tomohito Sato Manabu Kinoshita Tetsuo Yamamoto Masataka Ito Takafumi Nishida Masaru Takeuchi Daizoh Saitoh Shuhji Seki Yasuo Mukai 《PloS one》2015,10(2)
Ascorbic acid is an effective antioxidant and free radical scavenger. Therefore, it is expected that ascorbic acid should act as a radioprotectant. We investigated the effects of post-radiation treatment with ascorbic acid on mouse survival. Mice received whole body irradiation (WBI) followed by intraperitoneal administration of ascorbic acid. Administration of 3 g/kg of ascorbic acid immediately after exposure significantly increased mouse survival after WBI at 7 to 8 Gy. However, administration of less than 3 g/kg of ascorbic acid was ineffective, and 4 or more g/kg was harmful to the mice. Post-exposure treatment with 3 g/kg of ascorbic acid reduced radiation-induced apoptosis in bone marrow cells and restored hematopoietic function. Treatment with ascorbic acid (3 g/kg) up to 24 h (1, 6, 12, or 24 h) after WBI at 7.5 Gy effectively improved mouse survival; however, treatments beyond 36 h were ineffective. Two treatments with ascorbic acid (1.5 g/kg × 2, immediately and 24 h after radiation, 3 g/kg in total) also improved mouse survival after WBI at 7.5 Gy, accompanied with suppression of radiation-induced free radical metabolites. In conclusion, administration of high-dose ascorbic acid might reduce radiation lethality in mice even after exposure. 相似文献
89.
Eri Miyamoto-Mikami Koji Sato Toshiyuki Kurihara Natsuki Hasegawa Shumpei Fujie Satoshi Fujita Kiyoshi Sanada Takafumi Hamaoka Izumi Tabata Motoyuki Iemitsu 《PloS one》2015,10(3)
To elucidate the effects of endurance training on circulating irisin levels in young and middle-aged/older adults, and to determine the association between endurance training-induced alteration of irisin and reduction in body fat. Twenty-five healthy young (age 21 ± 1 years; 16 men, 9 women) and 28 healthy middle-aged/older adults (age 67 ± 8 years; 12 men, 16 women) participated in the study. Each age cohort was divided into two groups: the endurance-training group (14 young, 14 middle-aged/older) and the control group. Subjects in the training groups completed an 8-week endurance-training program (cycling at 60-70% peak oxygen uptake [O2peak] for 45 min, 3 days/week). Before and after the intervention, we evaluated serum irisin level, O2peak, and body composition. The increase in O2peak in the young and middle-aged/older training groups after the intervention period was significantly greater than those in the young and middle-aged/older control groups (P < 0.05). Serum irisin level was significantly increased in the middle-aged/older training group after the intervention period (P < 0.01), but not in the young training group. Furthermore, in the middle-aged/older training group, the endurance training-induced reduction in visceral adipose tissue area was negatively correlated with the change in serum irisin level (r = −0.54, P < 0.05). These results suggest a possible role for secreted irisin in the exercise-induced alteration of abdominal visceral fat in middle-aged and older adults. 相似文献
90.
Cumulative Incidence and Predictors of Progression in Corticosteroid-Na?ve Patients with Sarcoidosis
Yusuke Inoue Naoki Inui Dai Hashimoto Noriyuki Enomoto Tomoyuki Fujisawa Yutaro Nakamura Takafumi Suda 《PloS one》2015,10(11)