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41.
Kohyama K Sawada H Nonaka M Kobori C Hayakawa F Sasaki T 《Bioscience, biotechnology, and biochemistry》2007,71(2):358-365
The difficulty in masticating and swallowing rice cake was quantified. Healthy subjects ate pieces of rice cake (9 g and 3 g) and a modified product (9 g). We used electromyography to measure the activity of the jaw-closing and -opening muscles during chewing, as well as the suprahyoid muscle activity, laryngeal movement, and sound during swallowing. The smaller the rice cake, the shorter the mastication time, the fewer the number of chews, and the less the jaw-closing muscle activity. A modified rice cake product (9 g) was consumed with less mastication effort than the standard rice cake (9 g) and with the same effort as the standard (3 g). Both the sample amount and texture influenced mastication, although neither factor caused a significant difference in swallowing characteristics. These observations suggest that swallowing was induced when the bolus properties became suitable for swallowing, as healthy subjects could adjust their mastication technique according to the food amount and texture. 相似文献
42.
Maki K Holmes AR Watabe E Iguchi Y Matsumoto S Ikeda F Tawara S Mutoh S 《Microbiology and immunology》2007,51(11):1053-1059
The aim of this study was to compare the pharmacodynamics of the azole antifungal drugs fluconazole, itraconazole and ketoconazole, and the polyene antifungal amphotericin B, in a mouse model of disseminated Candida albicans infection. In order to directly compare effective serum concentrations of these antifungals, drug concentrations were assayed microbiologically by measuring inhibition of C. albicans mycelial growth (mMIC) in a mouse serum-based assay (serum antifungal titer). Efficacy in the mouse infection model was determined using an organ-based (kidney burden) endpoint. For all four drugs, the serum antifungal titers, 8 hr after administration of single doses of drugs at a range of drug concentrations, correlated closely with C. albicans kidney fungal burden in the mouse model. The results showed that determining serum antifungal titer may be used to accurately represent kidney fungal burden in a mouse model of disseminated candidiasis and allowed direct comparison of the pharmacodynamics of differing classes of antifungal drugs. 相似文献
43.
44.
Tsujikawa A Kiryu J Nonaka A Yamashiro K Nishiwaki H Honda Y Ogura Y 《American journal of physiology. Regulatory, integrative and comparative physiology》2000,279(3):R980-R989
Diabetes is associated with increased neural damage after transient cerebral ischemia. Recently, leukocytes, which are thought to play a central role in ischemia-reperfusion injury, have been suggested to be involved in exacerbated damage after transient ischemia in diabetic animals. The present study was designed to clarify whether the anticipated worse outcome after transient cerebral ischemia in diabetic animals was due to augmented leukocyte-mediated neural injury. Using rats with streptozotocin-induced diabetes of 4-wk duration, we investigated leukocyte-endothelial cell interactions during reperfusion after a transient 60-min period of retinal ischemia. Unexpectedly, postischemic diabetic retina showed no active leukocyte-endothelial cell interactions during reperfusion. The maximal numbers of rolling and accumulating leukocytes in diabetic retina were reduced by 73.6 and 41.2%, respectively, compared with those in nondiabetic rats. In addition, neither preischemic insulin treatment of diabetic rats nor preischemic glucose infusion of nondiabetic rats significantly influenced leukocyte-endothelial cell interactions during reperfusion. The present study demonstrated that high blood glucose concentration before induction of ischemia did not exacerbate leukocyte involvement in the postischemic retinal injury. Furthermore, diabetic retina showed suppressed leukocyte-endothelial cells interactions after transient ischemia, perhaps due to an adaptive mechanism that developed during the period of induced diabetes. 相似文献
45.
Sayuki Iijima Kentaro Matsuura Tsunamasa Watanabe Koji Onomoto Takashi Fujita Kyoko Ito Etsuko Iio Tomokatsu Miyaki Kei Fujiwara Noboru Shinkai Atsunori Kusakabe Mio Endo Shunsuke Nojiri Takashi Joh Yasuhito Tanaka 《PloS one》2015,10(2)
The levels of expression of interferon-stimulated genes (ISGs) in liver are associated with response to treatment with pegylated interferon (PEG-IFN) plus ribavirin (RBV). However, associations between the responses of ISGs to IFN-based therapy and treatment efficacy or interleukin-28B (IL28B) genotype have not yet been determined. Therefore, we investigated the early responses of ISGs and interferon-lambdas (IFN-λs) in peripheral blood mononuclear cells (PBMCs) during PEG-IFN/RBV plus NS3/4 protease inhibitor (PI) therapy. We prospectively enrolled 50 chronic hepatitis C patients with HCV genotype 1, and collected PBMCs at baseline, 8 and 24 h after the initial administration of PEG-IFN/RBV/PI. Levels of mRNAs for selected ISGs and IFN-λs were evaluated by real-time PCR. All 31 patients with a favorable IL28B genotype and 13 of 19 with an unfavorable genotype achieved sustained virological responses (SVR). Levels of mRNA for A20, SOCS1, and SOCS3, known to suppress antiviral activity by interfering with the IFN signaling pathway, as well as IRF1 were significantly higher at 8 h in patients with an unfavorable IL28B genotype than in those with a favorable one (P = 0.007, 0.026, 0.0004, 0.0006, respectively), especially in the non-SVR group. Particularly, the fold-change of IRF1 at 8 h relative to baseline was significantly higher in non-SVR than in SVR cases with an unfavorable IL28B genotype (P = 0.035). In conclusion, levels of several mRNAs of genes suppressing antiviral activity in PBMCs during PEG-IFN/RBV/PI differed according to IL28B genotypes, paralleling treatment efficacy. 相似文献
46.
Mitsuru Niwano Etsuko Mirumachi Masakazu Uramoto Kiyoshi Isono 《Bioscience, biotechnology, and biochemistry》2013,77(5):1359-1360
The Maillard reaction of DNA with ketoses was investigated. Several days of incubation of d-fructose 6-phosphate with deoxyribonucleotides or with polymer DNA in an aqueous buffer resulted in the formation of chromophores and fluorophores. Aminoguanidine and sodium cvanoborohydride inhibited the formation of fluorophores. Transition metal ions such as Cu2+, Fe3+, Fe2+, or Mn2 + promoted the formation of chromophores and fluorophores. Metal-chelating agents such as DETAPAC, citrate, and Desferal inhibited the formation of fluorophores. Superoxide dismutase and catalase also inhibited the formation of fluorophores. The transition metal ion-catalyzed autoxidation of d-fructose 6-phosphate or of the Heyns rearrangement products were to be partially involved in the glycation of DNA and subsequent formation of chromophores and of fluorophores. 相似文献
47.
Minoru Ishii Shunpei Uemoto Kunimitsu Fujieda Mizuo Nonaka Yukihiro Shoyama Yumi Miyahara Itsuo Nishioka 《Phytochemistry》1979,18(7):1211-1213
A new phenolic, hydroxyeucomic acid, and dopamine were isolated from Cattleya trianaei and their biological activities examined. 相似文献
48.
Tissue and subcellular distributions of an inhibitory GDP/GTP exchange protein (GDI) for the rho proteins by use of its specific antibody 总被引:3,自引:0,他引:3
K Shimizu K Kaibuchi H Nonaka J Yamamoto Y Takai 《Biochemical and biophysical research communications》1991,175(1):199-206
We have recently purified from bovine brain cytosol to near homogeneity a GDP/GTP exchange protein for the rho proteins, named rho GDI, that inhibits the dissociation of GDP from and the subsequent binding of GTP to the rho proteins. In the present study, we made a monoclonal antibody against rho GDI and studied its tissue distribution in rat and its subcellular distribution in rat cerebrum by use of this antibody. rho GDI was found in most rat tissues as described for the rho proteins. In rat cerebrum, rho GDI was mostly found in the cytosol of neuron body and synaptosome. In synaptosome, it was mainly found in the synaptic cytosol. 相似文献
49.
Many parasitoids have single‐locus complementary sex determination (sl‐CSD), which produces sterile or inviable males when homozygous at the sex determining locus. A previous study theoretically showed that small populations have elevated risks of extinction due to the positive feedback between inbreeding and small population size, referred to as the diploid male vortex. A few modeling studies have suggested that the diploid male vortex may not be as common because balancing selection at sex determining loci tends to maintain high allelic diversity in spatially structured populations. However, the generality of the conclusion is yet uncertain, as they were drawn either from models developed for particular systems or from a general‐purpose competition model. To attest the conclusion, we study several well‐studied host–parasitoid models that incorporate functional response specifying the number of attacked hosts given a host density and derive the conditions for a diploid male vortex in a single population. Then, we develop spatially structured individual‐based versions of the models to include female behavior, diploid male fertility, and temporal fluctuations. The results show that producing a handful of successful offspring per female parasitoid could enable parasitoid persistence when a typical number of CSD alleles are present. The effect of functional response depends on the levels of fluctuations in host abundance, and inviable or partially fertile diploid males and a small increase in dispersal can alleviate the risk of a diploid male vortex. Our work supports the generality of effective genetic rescue in spatially connected parasitoid populations with sl‐CSD. However, under more variable climate, the efficacy of the CSD mechanism may substantially decline. 相似文献
50.
Kazunari Momma Satoru Noguchi May Christine V. Malicdan Yukiko K. Hayashi Narihiro Minami Keiko Kamakura Ikuya Nonaka Ichizo Nishino 《PloS one》2012,7(12)
Rimmed vacuoles in myofibers are thought to be due to the accumulation of autophagic vacuoles, and can be characteristic in certain myopathies with protein inclusions in myofibers. In this study, we performed a detailed clinical, molecular, and pathological characterization of Becker muscular dystrophy patients who have rimmed vacuoles in muscles. Among 65 Becker muscular dystrophy patients, we identified 12 patients who have rimmed vacuoles and 11 patients who have deletions in exons 45–48 in DMD gene. All patients having rimmed vacuoles showed milder clinical features compared to those without rimmed vacuoles. Interestingly, the rimmed vacuoles in Becker muscular dystrophy muscles seem to represent autophagic vacuoles and are also associated with polyubiquitinated protein aggregates. These findings support the notion that rimmed vacuoles can appear in Becker muscular dystrophy, and may be related to the chronic changes in muscle pathology induced by certain mutations in the DMD gene. 相似文献