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1.
The effects of food availability and ambient temperature (Ta) on hibernation in the Japanese dormouse,Glirulus japonicus, were examined. When the dormice were deprived of food under natural environmental conditions in midwinter, they showed typical hibernation patterns; in contrast, the animals given ad lib food did not show continuous long-term torpor. Furthermore, exposure to constant low temperature did not affect the torpor patterns in the animals receiving adequate food. These results suggest that food availability plays a decisive role in the onset and maintenance of hibernation in this species, and that low Ta does not have a great influence on the torpor patterns in animals with access to food. This differs from the previous study that emphasized the importance of Ta in the occurrence of torpor and discounted the effects of food shortage.  相似文献   
2.
This report is concerned with the time course of changes of several enzymes during endogenous respiration. It was observed that enzymes such as deaminases, amidases and transaminases found in the mycelia increased in activity more or less during endogenous respiration. It was assumed that enzyme formation occurred as the result of glucose starvation or depression of carbohydrate metabolism during endogenous respiration of the mold mycelia on buffer solution.  相似文献   
3.
We studied the effects of hormone replacement therapy (HRT) with estrogen on postmenopausal changes in the production of bone-resorbing cytokines interleukin 1 beta (IL-1beta) and tumor necrosis factor alpha (TNFalpha). Both cytokines were measured in the supernatants of lipopolysaccharide (LPS)-stimulated whole-blood cells from 72 untreated and 44 HRT-treated women by ELISA. The levels of IL-1beta were significantly higher in women in their 40s and 50s and in postmenopausal women than in women in their teens, 20s and 30s, while the levels of TNFalpha did not show any changes related to age. Both levels in HRT-treated women were significantly lower than those in untreated women at almost every postmenopausal stage. In a prospective study, HRT induced significant declines in both levels. These results show that estrogen decreases the accelerated production of IL-1beta and reduces the production of TNFalpha in postmenopausal women at each postmenopausal stage, even in late-postmenopausal women.  相似文献   
4.
Studies were made on the effect of water level of culture medium on the mycelial compositions and enzyme production in Aspergillus sojae K. S. The mold was grown on the media of various water levels made of powder of defatted soybean and wheat granule. The mycelia grown on the medium of low water level produced more protease and α-amylase, consumed more oxygen, formed less ammonia, and were richer in 2 n H2SO4-soluble glycogen, 60% H2SO4-soluble carbohydrates, protein and RNA per mg dry weight than the mycelia grown on the medium of high water level. Chromatographic analyses were carried out for nucleotides, sugar phosphates and free carbohydrates in cold TCA-soluble fraction of the mycelia.  相似文献   
5.
Natural killer cell responses play a crucial role in virus clearance by the innate immune system. Although the killer immunoglobulin-like receptor (KIR) in combination with its cognate human leukocyte antigen (HLA) ligand, especially KIR2DL3-HLA-C1, is associated with both treatment-induced and spontaneous clearance of hepatitis C virus (HCV) infection in Caucasians, these innate immunity genes have not been fully clarified in Japanese patients. We therefore investigated 16 KIR genotypes along with HLA-B and -C ligands and a genetic variant of interleukin (IL) 28B (rs8099917) in 115 chronic hepatitis C genotype 1 patients who underwent pegylated-interferon-α2b (PEG-IFN) and ribavirin therapy. HLA-Bw4 was significantly associated with a sustained virological response (SVR) to treatment (P = 0.017; odds ratio [OR] = 2.50, ), as was the centromeric A/A haplotype of KIR (P = 0.015; OR 3.37). In contrast, SVR rates were significantly decreased in patients with KIR2DL2 or KIR2DS2 (P = 0.015; OR = 0.30, and P = 0.025; OR = 0.32, respectively). Multivariate logistic regression analysis subsequently identified the IL28B TT genotype (P = 0.00009; OR = 6.87, 95% confidence interval [CI] = 2.62 - 18.01), KIR2DL2/HLA-C1 (P = 0.014; OR = 0.24, 95% CI = 0.08 - 0.75), KIR3DL1/HLA-Bw4 (P = 0.008, OR = 3.32, 95% CI = 1.37 - 8.05), and white blood cell count at baseline (P = 0.009; OR = 3.32, 95% CI = 1.35 - 8.16) as independent predictive factors of an SVR. We observed a significant association between the combination of IL28B TT genotype and KIR3DL1-HLA-Bw4 in responders (P = 0.0019), whereas IL28B TT along with KIR2DL2-HLA-C1 was related to a non-response (P = 0.0067). In conclusion, combinations of KIR3DL1/HLA-Bw4, KIR2DL2/HLA-C1, and a genetic variant of the IL28B gene are predictive of the response to PEG-IFN and ribavirin therapy in Japanese patients infected with genotype 1b HCV.  相似文献   
6.
C60-based polyanionic high-spin clusters (S = 1–3) in their ground state have been prepared by successive chemical reductions of pristine C60 fullerene with potassium in the presence of dicyclohexano-18-crown-6-ether in solution. Intermolecular spin-triplet, quintet, and septet states arising from the C60-based polyanionic molecular clusters have been generated at ambient temperature and identified by CW-ESR and pulse-ESR-based two-dimensional (2D) electron spin transient nutation (2D-ESTN) spectroscopy in organic rigid glasses, for the first time. Intermolecular exchange interactions between mono- and polyanionic C60 fullerenes are ferromagnetic via bridging potassium metal cations. The molecular structures of the polyanionic high-spin C60 clusters in solution have been proposed by a well-established phenomenological spin Hamiltonian approach in terms of the D-tensor-based calculations for the high-spin clusters. The findings of the C60-based high-spin molecular clusters evidence the occurrence of an intramolecular triplet C60 dianion in the ground state. Unequivocal spin identification for molecular high-spin entities by 2D-ESTN spectroscopy and its powerfulness have been illustrated, emphasizing that the 2D-ESTN spectroscopy is useful for mixtures of molecular species with different spin multiplicities, characterized by a small g-anisotropy, for which the powerfulness of advanced high-frequency ESR spectroscopy is hampered.  相似文献   
7.
We investigated the effects of estradiol-treated females on the behavior of male budgerigars. In comparison to control females, females given implants of estradiol showed elevated nest behavior and darker cere color, which are characteristics of breeding females. After we confirmed the efficacy of estradiol treatment on behavior and morphology, each female was paired with a male mate. Males paired with estradiol-treated females showed more courtship behavior (auditory and visual display, and courtship feeding) to their mates than males paired with control females. These data indicate that budgerigar females with a high estrogen level enhance males' courtship behavior. Since males did not show response to estradiol-treated females soon after females were introduced, effects of estradiol-treated female budgerigars may be mediated by the endocrine system, rather than wholly by the nervous system, of males. Electronic Publication  相似文献   
8.
Gastric mucosal ulceration and gastric hemorrhage are frequently associated with treatment by non-steroid anti-inflammatory drugs (NSAIDs); however, no convenient biomarker-based diagnostic methods for these adverse reactions are currently available, requiring the use of endoscopic evaluation. We recently reported five biomarker candidates in serum which predict gastric injury induced by NSAIDs in rats, but were unable to clarify the mechanism of change in the levels of these biomarker candidates. In this study, we performed capillary electrophoresis–mass spectrometry-based metabolomic profiling in stomach and serum from rats in which gastric ulcer was induced by aspirin and prevented by co-administration of omeprazole and famotidine. Results showed drug-induced decreases in the levels of citrate, cis-aconitate, succinate, 3-hydroxy butanoic acid, and O-acetyl carnitine in all animals administered aspirin. In contrast, aspirin-induced decreases in the level of 4-hydroxyproline were suppressed by co-administration of omeprazole and famotidine. We consider that these changes were due to the prevention of gastric ulcer and decrease in the amount of collagen in stomach tissue by omeprazole and famotidine, without prevention of the NSAID-induced depression of mitochondrial function. In addition, the decreases in 4-hydroxyproline in the stomach was also detectable as changes in the serum. While further study is needed to clarify limitations of indications and extrapolation to humans, this new serum biomarker candidate of gastric injury may be useful in the monitoring of NSAID-induced tissue damage.  相似文献   
9.
Structure-activity relationship of sphingosine-1-phosphate receptor agonist was examined. In terms of reducing the flexibility of molecule, hit compound 1 was modified to improve S1P1 agonistic activity as well as selectivity over S1P3 agonistic activity. Novel S1P agonists with cinnamyl scaffold or 1,2,5,6-tetrahydropyridine scaffold were identified.  相似文献   
10.
4-Amino-3,3'-dichloro-5,4'-dinitrobiphenyl (ADDB) is a novel chemical exerting strong mutagenicity, especially in the absence of metabolic activation. In addition to mutagenicity, ADDB may also disrupt the endocrine system in vitro. ADDB may be discharged from chemical plants near the Waka River and could be unintentionally formed via post-emission modification of drainage water containing 3,3'-dichlorobenzidine (DCB), which is a precursor in the manufacture of polymers and dye intermediates in chemical plants. The main purpose of this study was to make a comprehensive survey of the behaviour and levels of ADDB and suspected starting material or intermediates of ADDB, i.e., DCB, 3,3'-dichloro-4,4'-dinitrobiphenyl (DDB), and 4-amino-3,3'-dichloro-4'-nitrobipheny (ADNB) in Waka River water samples. We also postulated the formation pathway of ADDB. Water samples were collected at five sampling sites from the Waka River four times between March 2003 and December 2004. Samples were passed through Supelpak2 columns, and adsorbed materials were then extracted with methanol. Extracts were used for quantification of ADDB and the related chemicals by HPLC on reverse-phase columns; mutagenicity was evaluated in the Salmonella assay using the O-acetyltransferase-overexpressing strain YG1024. High levels of ADDB, DCB, DDB, and ADNB (12.0, 20,400, 134.8, and 149.4ng/L-equivalent) were detected in the samples collected at the site where wastewater was discharged from chemical plants into the river. These water samples also showed stronger mutagenicity in YG1024 both with and without S9 mix than the other water samples collected from upstream and downstream sites. The results suggest that ADDB is unintentionally formed from DCB via ADNB in the process of wastewater treatment of drainage water containing DCB from chemical plants.  相似文献   
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