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71.
Peptides derived from soybean beta-conglycinin and pork protein stimulate cholecystokinin (CCK) secretion from the enteroendocrine cells (EECs) and suppress food intake. Here we examined CCK-releasing activities from the enteroendocrine cell line STC-1, in peptides derived from underutilized legumes, and found much higher activity in the peptic hydrolysate of Country beans (CBP) compared to that from other legume-derived peptides including beta-conglycinin peptone. Active components in CBP were separated into acetonitrile-soluble fractions, but the activities were abolished after pronase treatment. To identify the Country bean protein containing the active peptides, Country bean protein extracts in an alkaline solution (CBE) were fractionated based on isoelectric point or molecular weight. Peptones prepared from CBE fractions containing a 51 kDa major protein stimulated CCK release, but other fractions did not. N-Terminal sequence analysis indicated that the 51 kDa protein is a phaseolin-like globular protein, and we designated this protein dolicholin. These results indicate that Country bean-derived peptides are very potent legume peptides in stimulating CCK secretion from EECs and that the stimulant peptides originate from dolicholin, a newly identified phaseolin-like globular protein in Country beans.  相似文献   
72.
IRAK-4 is a protein kinase that is pivotal in mediating signals for innate immune responses. Here, we report that IRAK-4 signaling is also essential for eliciting adaptive immune responses. Thus, in the absence of IRAK-4, in vivo T cell responses were significantly impaired. Upon T cell receptor stimulation, IRAK-4 is recruited to T cell lipid rafts, where it induces downstream signals, including protein kinase C activation through the association with Zap70. This signaling pathway was found to be required for optimal activation of nuclear factor kappaB. Our findings suggest that T cells use this critical regulator of innate immunity for the development of acquired immunity, suggesting that IRAK-4 may be involved in direct signal cross talk between the two systems.  相似文献   
73.
The anticholinergic effects of 7 benzodiazepines, bromazepam, camazepam, chlordiazepoxide, diazepam, lorazepam, medazepam and triazolam, were compared by examining their inhibitory effects on the acetylcholine receptor-operated potassium current (I(K).(ACh)) in guinea-pig atrial myocytes. All of these benzodiazepines (0.3-300 μM) inhibited carbachol (1 μM)-induced I(K).(ACh) in a concentration-dependent manner. The ascending order of IC(50) values for carbachol-induced I(K).(ACh) was as follows; medazepam, diazepam, camazepam, triazolam, bromazepam, lorazepam and chlordiazepoxide (>300 μM). The compounds, except for bromazepam, also inhibited I(K).(ACh) activated by an intracellular loading of 100 μM guanosine 5'-[γ-thio]triphosphate (GTPγS) in a concentration-dependent manner. The ascending order of IC(50) values for GTPγS-activated I(K).(ACh) was as follows; medazepam, diazepam, camazepam, lorazepam, triazolam chlordiazepoxide (>300 μM) and bromazepam (>300 μM). To clarify the molecular mechanism of the inhibition, IC(50) ratio, the ratio of IC(50) for GTPγS-activated I(K).(ACh) to carbachol-induced I(K).(ACh), was calculated. The IC(50) ratio for camazepam, diazepam, lorazepam, medazepam and triazolam was close to unity, while it for chlordiazepoxide could not be calculated. These compounds would act on the GTP binding protein and/or potassium channel to achieve the anticholinergic effects in atrial myocytes. In contrast, since the IC(50) ratio for bromazepam is presumably much higher than unity judging from the IC(50) values (104.0 ± 30.0 μM for carbachol-induced I(K).(ACh) and >300 μM for GTPγS-activated I(K).(ACh), it would act on the muscarinic receptor. In summary, benzodiazepines had the anticholinergic effects on atrial myocytes through inhibiting I(K).(ACh) by different molecular mechanisms.  相似文献   
74.
Fisheries Science - Two sediment cores were collected from two sites in Nagatsura-Ura Lagoon, the mouth of which was destroyed in the 2011 Tohoku-oki tsunami. Although sediment conditions differed...  相似文献   
75.
Cushing's disease caused by pituitary corticotroph adenoma is a common endocrine disease in dogs. A characteristic biochemical feature of corticotroph adenomas is their relative resistance to negative feedback by glucocorticoids. In this study, we examined gene expression related to adrenocorticotropic hormone (ACTH) production and secretion, and the negative feedback by glucocorticoids in canine corticotroph adenoma. We used resected corticotroph adenomas from 10 dogs with Cushing's disease. In order to investigate the alteration of gene expression between corticotroph adenoma and normal corticotrophic cells, ACTH-positive cells in the anterior lobe were microdissected using a laser-capture microdissection system, and mRNA levels of proopiomelanocortin (POMC), corticotropin releasing hormone receptor 1 (CRHR1), glucocorticoid receptor (GR), mineralocorticoid receptor (MR), and 11 beta hydroxysteroid dehydrogenase (11HSD) type 1 and type 2 were determined using real-time RT-PCR. POMC, CRHR1, and 11HSD2 mRNA levels in corticotroph adenoma were greater than those in normal corticotrophic cells (POMC, 5.5-fold; CRHR1, 4.9-fold; 11HSD2, 4.2-fold, P<0.01, respectively). MR and 11HSD1 mRNA levels in corticotroph adenoma were lower than those in normal corticotrophic cells (MR, 2.2-fold; 11HSD1, 2.9-fold, P<0.01, respectively). GR mRNA levels did not differ between corticotroph adenoma and normal corticotrophic cells. Our results may help to understand the increased ACTH production and the resistance to negative feedback suppression by glucocorticoids in canine corticotroph adenomas. These changes in gene expression may have a role in the growth of canine corticotroph adenoma, and help elucidate the pathophysiology of dogs with Cushing's disease.  相似文献   
76.
77.
SUMMARY: Cathepsin S was purified from carp hepatopancreas to homogeneity up to 300-fold. The amino acid sequence of its NH2-terminus was determined to be V-P-D-A-M-D-W-Y-N-K-G-Y-V-T-D-V-K-N-Q. On the contrary, that of purified cathepsin L from carp hepatopancreas was to be V-P-N-S-L-D-W-R-E-K-G. Purified cathepsin S consisted of a single chain with 37 kDa estimated by sodium dodecylsulfate–polyacrylamide gel electrophoresis. The enzyme had strong hydrolytic activity toward Z-Phe-Arg-MCA with the pH optimum of 7.0, but this lacked the ability to hydrolyze most of the other MCA substrates. The optimum pH of cathepsin S for protein substrate (carp myosin heavy chain) was also to be pH 7.0. These properties of purified cathepsin S obviously differ from cathepsins B and L. The enzyme activity was totally inhibited by E-64, leupeptin, 5–5'-dithiobis (2-nitro-benzoic acid) and p -tosyl-lys chloromethylketone as well.  相似文献   
78.
To clarify the effect of nutritive conditions on changes in immune cells in Japanese Black (JB) calves during the growth period, leukocyte populations were analyzed in ten healthy JB calves managed in one herd. The calves were divided into two groups: five calves in Group 1 were given insufficient nutrition, and the other five calves in Group 2 received adequate nutrition. The levels of serum total cholesterol and glucose were significantly lower in Group 1 than in Group 2 at 1 month. The numbers of CD3+, CD4+ and CD8+ cells tended to be lower in Group 1 than in Group 2 at months 1 and 2, and the difference in CD4+ was significant at month 2. The number of MHC class-II(+high) cells was significantly lower in Group 1 than in Group 2 at months 1 and 2. These results suggest that adequate nutrition might stimulate an increase in immune cells in calves during the growth period.  相似文献   
79.
The effects of alpha-cyclodextrin-horseradish oil complex (CD-HR) on methane production and ruminal fermentation were studied in vitro and in steers. In the in vitro study, diluted ruminal fluid (30 mL) was incubated anaerobically at 38 degrees C for 6 h with or without CD-HR, using cornstarch as substrate. The CD-HR was added at various concentrations (0, 0.17, 0.85 and 1.7 g/L). Treatment affected neither the pH of the medium nor the number of protozoa. Total VFA increased in a linear manner (P = 0.02), and NH3-N decreased quadratically (P = 0.04) as the concentration of CD-HR increased from 0.17 g/L to 1.7 g/L. Molar proportions of acetate decreased in a linear manner (P = 0.03), and propionate increased linearly (P = 0.008) with increasing concentrations of CD-HR. Production of methane was inhibited up to 90%, whereas accumulation of dihydrogen was increased 36-fold by 1.7 g/L of CD-HR supplementation relative to controls. The effect of CD-HR on methane production, ruminal fermentation and microbes, and digestibility was further investigated in vivo using four Holstein steers in a crossover design. The CD-HR supplement was mixed into the concentrate portion of a (1.5:1) Sudangrass hay plus concentrate mixture that was fed twice daily to the steers. Ruminal samples were collected 0, 2, and 5 h after the morning feeding. No effects of CD-HR supplementation on ruminal pH (P = 0.63) or protozoal numbers (P = 0.44) were observed. Molar proportion of acetate was decreased (P = 0.04) and propionate was increased (P = 0.005) by CD-HR treatment. Molar proportion of butyrate was increased (P = 0.05) in CD-HR-supplemented steers. Ruminal NH3-N was decreased (P = 0.05) by treatment. Blood plasma glucose concentration was increased (P = 0.02) and urea-N was decreased (P = 0.04) with CD-HR supplementation. Daily DMI was decreased (P = 0.04), and apparent digestibility of DM (P = 0.13), NDF (P = 0.14), and CP tended (P = 0.14) to be increased by treatment. Methane production was decreased (P = 0.03) by 19%, and the number of methanogens was also decreased (P = 0.03). Although N retention (P = 0.11), total viable bacteria (P = 0.15), and sulfate-reducing bacteria (P = 0.17) were not significantly altered by treatment, tendencies for increases were noted with CD-HR supplementation. The number of cellulolytic (P = 0.38) and acetogenic bacteria (P = 0.32) remained unchanged by treatment. These results indicate that CD-HR supplementation can be used to decrease methane production in steers.  相似文献   
80.
OBJECTIVE: To determine whether small intestinal ischemia and reperfusion induces bacterial translocation and proinflammatory cytokine response in either the systemic or portal circulation in dogs. ANIMALS: 17 healthy adult Beagles. PROCEDURE: The superior mesenteric artery (SMA) was occluded for 0 (group-3 dogs), 30 (group-1 dogs), or 60 (group-2 dogs) minutes, followed by reperfusion for 180 minutes; serum lactate and endotoxin concentrations and tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and IL-6 activities in the systemic and portal circulation and intramucosal pH were measured at various time points. RESULTS: In group-2 dogs, TNFalpha activity was found to be significantly increased in the portal circulation, peaking at 60 minutes of reperfusion; TNF-alpha activity, in the systemic circulation, gradually increased from 60 minutes of reperfusion to the end of the experiment; however, the increase was not significant. In group-1 and -2 dogs, IL-6 activities significantly and gradually increased in the systemic and portal circulation during the reperfusion phase, and the magnitude of these increases was dependent on the duration of the ischemic phase. There were no significant changes in IL-1beta activity or endotoxin concentration in any dog group. CONCLUSIONS AND CLINICAL RELEVANCE: Results of the our study indicate that intestinal ischemia and reperfusion leads to significant increases of the circulating TNF-alpha and IL-6 activities, depending on the duration of the ischemia phase, in the absence of detectable endotoxin in the circulation. This finding suggests that intestinal ischemia and reperfusion induces a systemic proinflammatory cytokine response in dogs.  相似文献   
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