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101.
Construction of a taste-blind medaka fish and quantitative assay of its preference-aversion behavior 总被引:1,自引:0,他引:1
In vertebrates, the taste system provides information used in the regulation of food ingestion. In mammals, each cell group within the taste buds expresses either the T1R or the T2R taste receptor for preference-aversion discrimination. However, no such information is available regarding fish. We developed a novel system for quantitatively assaying taste preference-aversion in medaka fish. In this study, we prepared fluorescently labeled foods with fine cavities designed to retain tastants until they were bitten by the fish. The subjects were fed food containing a mixture of amino acids and inosine monophosphate (AN food), denatonium benzoate (DN food) or no tastant (NT food), and the amounts of ingested food were measured by fluorescence microscopy. Statistical analysis of the fluorescence intensities yielded quantitative measurements of AN food preference and DN food aversion. We then generated a transgenic fish expressing dominant-negative Galpha(i2) both in T1R-expressing and in T2R-expressing cells. The feeding assay revealed that the transgenic fish was unable to show a preference for AN food and an aversion to DN food. The assay system was useful for evaluating taste-blind behaviors, and the results indicate that the two taste signaling pathways conveying preferable and aversive taste information are conserved in fish as well as in mammals. 相似文献
102.
Mashiko S Ishihara A Iwaasa H Moriya R Kitazawa H Mitobe Y Ito J Gomori A Matsushita H Takahashi T MacNeil DJ Van der Ploeg LH Fukami T Kanatani A 《Obesity (Silver Spring, Md.)》2008,16(7):1510-1515
Objective: To further address the function of the Y5 receptor in energy homeostasis, we investigated the effects of a novel spironolactone Y5 antagonist in diet-induced obese (DIO) mice. Methods and Procedures: Male C57BL/6 or Npy5r−/− mice were adapted to high-fat (HF) diet for 6–10 months and were submitted to three experimental treatments. First, the Y5 antagonist at a dose of 10 or 30 mg/kg was administered for 1 month to DIO C57BL/6 or Npy5r−/− mice. Second, the Y5 antagonist at 30 mg/kg was administered for 1.5 months to DIO C57BL/6 mice, and insulin sensitivity was evaluated using an insulin tolerance test. After a recovery period, nuclear magnetic resonance measurement was performed to evaluate body composition. Third, DIO mice were treated with the Y5 antagonist alone, or in combination with 10% food restriction, or with another anorectic agent, sibutramine at 10 mg/kg, for 1.5 months. Plasma glucose, insulin, and leptin levels, and adipose tissue weights were quantified. Results: The spironolactone Y5 antagonist significantly reduced body weight in C57BL DIO mice, but not in Npy5r−/− DIO mice. The Y5 antagonist produced a fat-selective loss of body weight, and ameliorated obesity-associated insulin resistance in DIO mice. In addition, the Y5 antagonist combined with either food restriction or sibutramine tended to produce greater body weight loss, as compared with single treatment. Discussion: These findings demonstrate that the Y5 receptor is an important mediator of energy homeostasis in rodents. 相似文献
103.
This paper presents a framework for annotating protein domains with predicted domain-domain interaction networks. Specially, domain annotation is formalized as a multi-class classification problem in this work. The numerical experiments on InterPro domains show promising results, which proves the efficiency of our proposed methods. 相似文献
104.
Nakano K Higashi T Hashimoto K Takagi R Tanaka Y Matsushita S 《Biochemical and biophysical research communications》2008,373(2):286-291
Five types of dopamine receptors, termed D1 to D5, have been identified to date. The D1 and D5 receptors form the D1-like group that couples with the Gαs class of G proteins, while D2, D3 and D4 form the D2-like group that couples with the Gαi class of G proteins. A D2-like-receptor (D2-like-R) antagonist L750667 induced dendritic cell (DC)-mediated Th17 differentiation. In contrast, a D1-like-R antagonist SCH23390 inhibited DC-mediated Th17 differentiation. The D1-like-Rs were expressed on both DCs and T cells, whereas D2-like-Rs were marginally expressed on CD4+CD45RA+ naïve T cells. In addition, SCH23390 had the ability to prevent experimental autoimmune encephalomyelitis (EAE) in mice. Spleen cells from EAE mice showed decreased IL-17 production, when SCH23390 was administered. Adoptive transfer of DCs treated with SCH23390 successfully prevented EAE. These findings indicate that antagonizing D1-like-Rs on DCs inhibits Th17 differentiation, thereby leading to an amelioration of EAE. 相似文献
105.
FK506 and dexamethasone were used to investigate whether or not immunosuppression affects H. pylori colonization and gastric mucosal damage induced by Helicobacter pylori in Mongolian gerbils. Two weeks after H. pylori infection, FK506 and dexamethasone or vehicle alone were subcutaneously administered once daily for the following 2 weeks. FK506 or vehicle alone was administered subcutaneously once daily for 5 weeks (1 week before and 4 weeks after infection). In H. pylori-infected animals for 4 weeks, hemorrhagic erosions and inflammatory responses (neutrophil infiltration and lymphoid follicle formation) were induced in gastric mucosa at an incidence of 100%. Both FK506 and dexamethasone administered for 2 weeks markedly reduced such mucosal changes. In these animals, H. pylori viability in the stomach was significantly elevated. FK506 administered for 5 weeks also significantly inhibited the hemorrhagic erosions, edema and neutrophil infiltration in the stomach. H. pylori viability was slightly elevated as compared with the control. It was concluded that the host immune responses might play dual roles both by deteriorating gastritis induced by H. pylori and by protecting against H. pylori infection in its early stage. 相似文献
106.
Takehiro Yamamoto Masamitsu Tomiyama Hajime Mita Koji Sode Isao Karube 《FEMS microbiology letters》1990,66(1-3):187-192
The hydB gene of Escherichia coli, which is related with the expression of hydrogenase activity, was cloned into the plasmid (pES1). Using the maxicell protein-labeling method, the molecular weight of hydB gene product was estimated. Comparing between the gene products from the mutant strains and that of the hydB genes cloned strains, the molecular weight of the gene product was 35,000 Mr. Similarly, the molecular weight of the gene product of hydA, which had been previously cloned, was determined by maxicell analysis. The molecular weight of hydA gene product was estimated to be 80,000 Mr. Using deletion analysis and Tn1000 insertional inactivation of hydA's function, the hydA coding region was estimated between 2.2 kb and 2.8 kb in a 3.1 kb EcoRI-MluI fragment on the recombinant plasmid pEH3. 相似文献
107.
108.
Regiane Marinho da Silva Gui Mi Ko Rinaldo Florêncio Silva Ludmila Cabreira Vieira Rafael Vicente de Paula Júlio Takehiro Marumo Amanda Ikegami Maria Helena Bellini 《Biological trace element research》2018,182(2):303-308
Acute kidney injury (AKI) is an important health problem and can be caused by number of factors. The use of aminoglycosides, such as gentamicin, is one of these factors. Recently, an effort has been made to find biomarkers to guide treatment protocols. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was used to estimate the contents of Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn in serum and urine of the healthy, AKI, and spontaneous recovery (SR) groups of animals. The animal model of AKI and SR was validated by measuring serum and urinary urea and creatinine. The quantitative determination of the elements showed a decrease in serum levels of Ca, and Fe in the AKI group (P<0.01 vs. healthy), with a return to normal levels in the SR group, without a significant difference between the healthy and SR groups. In the urine samples, there was a decrease in P and Na levels in the AKI group (P<0.001 and P<0.01 vs. healthy), but Ca levels were increased in this group compared with the healthy and SR groups (P<0.01). These findings indicate that mineral elements might be useful as biomarkers for AKI. 相似文献
109.
Suleiman M. Saidi Yoshio Lijima William K. Sang Anderson K. Mwangudza Joseph O. Oundo Kenichiro Taga Masanori Aihara Kenichi Nagayama Hiroyuki Yamamoto Peter G. Waiyaki Takeshi Honda 《Microbiology and immunology》1997,41(10):773-778
Diarrheal diseases are major causes of morbidity and mortality among children in developing countries. We have analyzed the causative agents of diarrhea in children under five years of age who resided in rural environments but attended a hospital in Malindi, a coastal town in Kenya. Bacterial diarrhea was found in 239 (27.7%) of 862 patients with diarrhea. Diarrheagenic Escherichia coli, including enteropathogenic, enterotoxigenic, and enterohaemorrhagic strains, was isolated from 119 (13.8%) patients, followed by Salmonella spp. (63 cases, 7.3%) and Shigella spp. (56 cases, 6.5%). Intestinal parasites were found in 109 (12.6%) of the patients. Entamoeba histolytica and Giardia lamblia were found in 67 (7.8%) and 42 (4.9%) of the cases, respectively. Rotavirus was found in 69 (16.1%) of 428 cases, a part of the 862 cases. Significant differences in age distribution were seen in diarrheal cases due to Campylobacter spp., G. lamblia, and rotavirus. No significant seasonal incidence of specific pathogens was found, but the number of diarrheal patients was significantly correlated to rainfall. Drinking water was contaminated with bacteria at concentrations ranging from 103 to 106 CFU/ml in 98% of the households and by coliform bacteria at concentrations of 102 to 105 CFU/ml in 72% of the households. These results suggest that the main routes of infection may be contaminated drinking water and fecal-oral transmission of enteric pathogens. Consequently, we propose that the enhancement of hygienic practice through health education is a feasible control measure of diarrhea in the study area. 相似文献
110.
Takehiro Kaida Osamu Kozawa Takeshi Ito Kumiko Tanabe Hidenori Ito Hiroyuki Matsuno Masayuki Niwa Hideo Miyata Toshihiko Uematsu Kanefusa Kato 《Experimental cell research》1999,246(2):327
In the present study, we examined the effect of vasopressin on the induction of the low-molecular-weight heat shock proteins heat shock protein 27 (HSP27) and αB-crystallin in an aortic smooth muscle cell line, A10 cells. Vasopressin induced a time-dependent accumulation of HSP27 and αB-crystallin. The stimulatory effects of vasopressin were dose-dependent over the range 0.1 nmol/L to 0.1 μmol/L. The EC50values for vasopressin were 2 (HSP27) and 4 nmol/L (αB-crystallin). Vasopressin induced increases in the levels of the mRNAs for HSP27 and αB-crystallin. 12-O-Tetradecanoylphorbol 13-acetate (TPA), a protein kinase C (PKC)-activating phorbol ester, induced an accumulation of HSP27 (EC50, 20 nmol/L) and αB-crystallin (EC50, 2 nmol/L). In contrast, 4α-phorbol 12,13-didecanoate, a non-PKC-activating phorbol ester, had no such effect. Staurosporine and calphostin C, inhibitors of PKC, significantly reduced the vasopressin-induced accumulation of HSP27 and αB-crystallin as well as that induced by TPA. BAPTA/AM and TMB-8, inhibitors of intracellular Ca2+mobilization, significantly reduced the vasopressin-induced accumulation of HSP27 and αB-crystallin. These results strongly suggest that vasopressin stimulates the induction of HSP27 and αB-crystallin via PKC activation in vascular smooth muscle cells and that this effect of vasopressin is dependent on intracellular Ca2+mobilization. 相似文献