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41.
K Kasai T Emoto M Hiraiwa H Kuroda A Yamazaki Y Hattori S Shimoda 《Metabolism: clinical and experimental》1990,39(7):709-713
In an attempt to elucidate possible mechanism(s) for stimulated arachidonic acid metabolism by phorbol 12-myristate 13-acetate (PMA) and epidermal growth factor (EGF) in porcine thyroid cells, we examined the effects of protein kinase inhibitors, isoquinolinesulfonamide derivatives (H-7 and HA-1004), and cycloheximide. The production of PGE2 stimulated by either PMA or EGF was strongly inhibited by H-7, with an ID50 value of approximately 20 to 25 mumol/L in each case, as well as by cycloheximide, with an ID50 value of less than 0.5 micrograms/mL in each case. In contrast, 100 mumol/L of HA-1004 showed less inhibition of PGE2 production provocated by either PMA or EGF. On the other hand, PGE2 production in basal or stimulated condition by exogenously added arachidonic acid, was inhibited to an even lesser extent by both H-7 and cycloheximide. The EGF- and PMA-stimulated release of 3H-arachidonic acid from the cells was also strongly inhibited by H-7 and cycloheximide. These results suggest an induction of synthesis of some proteins responsible for the release of arachidonic acid, which might be attributed to protein kinase-C activation in arachidonic acid metabolism stimulated by PMA or EGF. Moreover, PGE2 production was potently induced by PMA and slightly by EGF in the cyclooxygenase-inactivated cells by acetyl salicylate pretreatment, which also suggests that both agents might induce the synthesis of cyclooxygenase in cultured porcine thyroid cells, although we did not measure its activity. 相似文献
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Sasaki S Katagiri A Tsuji T Shimoda T Amano K 《International journal of obesity (2005)》2003,27(11):1405-1410
OBJECTIVE: To examine associations between rate of eating and macronutrient and dietary fiber intake, and body mass index (BMI). DESIGN: Cross-sectional study. SUBJECTS: A total of 1695 18-y-old female Japanese dietetic students. MEASUREMENTS: Macronutrient intake (protein, carbohydrate, and fat) and dietary fiber intake were assessed over a 1-month period with a validated, self-administered, diet history questionnaire. Body height and weight and rate of eating (according to five categories) were self-reported. RESULTS: Among the nutrients examined, only dietary fiber intake weakly, but significantly, and negatively correlated with BMI in a multiple regression analysis. The rate of eating showed a significant and positive correlation with BMI. The mean BMI was higher by 2.2, 1.5, 1.0, and 0.5 kg/m(2) in the 'very fast', 'relatively fast', 'medium', and 'relatively slow' groups, respectively, compared with the 'very slow' rate of eating group. This correlation remained evident after adjustment for nutrient intake. CONCLUSIONS: Rate of eating showed a significant and positive correlation with BMI, whereas only dietary fiber intake showed a weak correlation with BMI. 相似文献
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Chieko Sakano Makoto Kuroda Tsuyoshi Sekizuka Taisei Ishioka Yukio Morita Akihide Ryo Hiroyuki Tsukagoshi Yuko Kawai Nobuko Inoue Hayato Takada Yumiko Ogaswara Atsuyoshi Nishina Masa-aki Shimoda Kunihisa Kozawa Kazunori Oishi Hirokazu Kimura 《Journal of clinical microbiology》2013,51(1):328-330
Whole-genome sequencing of non-H2S-producing Salmonella enterica serovar Typhimurium and S. enterica serovar Infantis isolates from poultry meat revealed a nonsense mutation in the phsA thiosulfate reductase gene and carriage of a CMY-2 β-lactamase. The lack of production of H2S might lead to the incorrect identification of S. enterica isolates carrying antimicrobial resistance genes. 相似文献
46.
Seiya Jingushi Jun-ichi Shida Yukihide Iwamoto Takayuki Kinoshita Yoshiyuki Hiyama Makoto Tamura 《Connective tissue research》2013,54(4):242-248
Fibroblast growth factor-2 (FGF-2) has the potential to regenerate damaged articular cartilage tissue due to its exerting anabolic effects on chondrocytes. However, FGF-2 is involved in pathogenesis of rheumatoid arthritis, where the joint is destructed. The study aims at clarifying the effects of FGF-2 on joints. When radiolabeled FGF-2 was injected into knee joints of C57Bl/10 mice, a transient binding was observed in the superficial and intermediate zones of the articular cartilage as well as in the synovium and perichondrium. An FGF-2 injection (5 μg) caused synovial hyperplasia adjacent to the articular cartilage on day 7, cartilage formation adjacent to the articular cartilage on day 14, and osteophyte on day 21. The intensity of safranin-O staining of the articular cartilage increased on day 14. These changes were dose-dependent. No destructive changes in the joints were observed. In a joint, transient exposure of FGF-2 caused proliferative changes, but not destructive changes. 相似文献
47.
Kanako Iwasaki Tomoyuki Fujiyama Shinya Nakata Minjeong Park Chika Miyoshi Noriko Hotta-Hirashima Aya Ikkyu Miyo Kakizaki Fumihiro Sugiyama Seiya Mizuno Manabu Abe Kenji Sakimura Satoru Takahashi Hiromasa Funato Masashi Yanagisawa 《The Journal of neuroscience》2021,41(12):2733
Sleep is regulated in a homeostatic manner. Sleep deprivation increases sleep need, which is compensated mainly by increased EEG δ power during non-rapid eye movement sleep (NREMS) and, to a lesser extent, by increased sleep amount. Although genetic factors determine the constitutive level of sleep need and sleep amount in mice and humans, the molecular entity behind sleep need remains unknown. Recently, we found that a gain-of-function Sleepy (Slp) mutation in the salt-inducible kinase 3 (Sik3) gene, which produces the mutant SIK3(SLP) protein, leads to an increase in NREMS EEG δ power and sleep amount. Since Sik3Slp mice express SIK3(SLP) in various types of cells in the brain as well as multiple peripheral tissues from the embryonic stage, the cell type and developmental stage responsible for the sleep phenotype in Sik3Slp mice remain to be elucidated. Here, we generated two mouse lines, synapsin1CreERT2 and Sik3ex13flox mice, which enable inducible Cre-mediated, conditional expression of SIK3(SLP) in neurons on tamoxifen administration. Administration of tamoxifen to synapsin1CreERT2 mice during late infancy resulted in higher recombination efficiency than administration during adolescence. SIK3(SLP) expression after late infancy increased NREMS and NREMS δ power in male synapsin1CreERT2; Sik3ex13flox/+ mice. The expression of SIK3(SLP) after adolescence led to a higher NREMS δ power without a significant change in NREMS amounts. Thus, neuron-specific expression of SIK3(SLP) after late infancy is sufficient to increase sleep.SIGNIFICANCE STATEMENT The propensity to accumulate sleep need during wakefulness and to dissipate it during sleep underlies the homeostatic regulation of sleep. However, little is known about the developmental stage and cell types involved in determining the homeostatic regulation of sleep. Here, we show that Sik3Slp allele induction in mature neurons in late infancy is sufficient to increase non-rapid eye movement sleep amount and non-rapid eye movement sleep δ power. SIK3 signaling in neurons constitutes an intracellular mechanism to increase sleep. 相似文献
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