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371.
Takeshi Sakaki Katsuko Niino Hirohiko Sakuma Shiro Sugawara 《Bioscience, biotechnology, and biochemistry》2013,77(12):3121-3128
Two simple methods, the Tenax GC method and the active carbon method, have been developed to analyze the headspace volatiles of tobacco. The headspace volatiles swept by helium from cut tobacco were collected by either Tenax GC or active carbon and were analyzed by gas chromatography after desorption by heating the Tenax GC or by extracting the active carbon with dichloromethane. The gas chromatograms of the headspace volatiles of flue-cured tobacco obtained by these two methods differed. Both methods showed good reproducibility and were applied to the analysis of the headspace volatiles of American and Japanese flue-cured tobacco samples. By principal component analysis, three or four principal components were. extracted from the 15 selected peaks of the headspace volatiles of these samples that had been obtained from both the Tenax GC and the active carbon methods. 相似文献
372.
373.
Shunji Nagaoka Yukiko Bito Rie Sakuma Hiroko Nomura Tadayoshi Hata Junpei Nishiyama Yutaka Hirata 《Biological Sciences in Space》2003,17(3):265-266
We analyzed and compared the frequency components of the heart rate variability in human neonate, rat, white chicken, turtle, and frog during the developments. Frequency analysis with autocorrelation-FFT method was applied to the heart rate and respiration waves to calculate the respiration induced frequency component in the power spectra. The comparative analysis of the cardiopulmonary reflex in human and rat neonates resulted in a similar developmental progress. In case of human immature neonate, respiration induced frequency component in the heart rate variability was negligible at day-old 0, and significantly increased at postnatal 1 month. The rat neonates also showed no or negligible respiration induced components until days 8 and it became significant approximately postnatal 1 month. The white chicken also indicated negligible respiration induced component before and a few days after hatching, and became significant after 38 days-old (17 days post hatching). However the frog and the turtle indicated no clear response in entire periods of the development even in adult. The results strongly suggested that gravity may be a possible essential factor of the appearance of the post natal development of the cardiopulmonary reflex. 相似文献
374.
Sadanori Okada Takeshi Morimoto Hisao Ogawa Mio Sakuma Hirofumi Soejima Masafumi Nakayama Hideaki Jinnouchi Masako Waki Yasuhiro Akai Hitoshi Ishii Yoshihiko Saito investigators for the Japanese Primary Prevention of Atherosclerosis with Aspirin for Diabetes trial 《PloS one》2016,11(1)
Background
Low-dose aspirin is widely recommended for patients at high risk for cardiovascular disease (CVD); however, it remains uncertain whether long-term treatment adversely affects renal function in patients with diabetes.We investigated whether long-term low-dose aspirin affects renal dysfunction in patients with diabetes.Methods
We conducted a randomized controlled trial (RCT), the Japanese Primary Prevention of Atherosclerosis with Aspirin for Diabetes (JPAD) trial, to evaluate low-dose aspirin as primary prevention for CVD in patients with type 2 diabetes. We followed the patients with negative urine dipstick albumin of the JPAD trial in a cohort study after the RCT period was completed. Patients were randomly allocated to receive aspirin (81 mg or 100 mg daily, aspirin group) or no aspirin (no aspirin group). After the RCT, the treating physician decided whether to administer aspirin. We evaluated the incidence of positive urine dipstick albumin and annual changes in estimated glomerular filtration rate (eGFR).Results
Positive urine dipstick albumin developed in 297 patients in the aspirin group (n = 1,075) and 270 patients in the no aspirin group (n = 1,098) during follow-up (median, 8.5 years). Intention-to-treat analysis showed low-dose aspirin did not increase the incidence of positive urine dipstick albumin (hazard ratio [HR], 1.17; 95% confidence interval [CI], 0.995–1.38). On-treatment analysis yielded similar results (HR, 1.08; 95% CI, 0.92–1.28). Multivariable analysis showed the incidence of positive urine dipstick albumin was higher among the elderly and those with elevated serum creatinine, high hemoglobin A1c, or high blood pressure; however, low-dose aspirin did not increase the risk of positive urine dipstick albumin. There were no significant differences in annual changes in eGFR between the groups (aspirin, −0.8 ± 2.9; no aspirin, −0.9 ± 2.5 ml/min/1.73m2/year).Conclusion
Long-term low-dose aspirin does not affect eGFR and positive urine dipstick albumin in patients with type 2 diabetes. 相似文献375.
Yohei Sakaki Mitsuru Tashiro Moe Katou Chiseko Sakuma Takako Hirano Wataru Hakamata 《Bioscience, biotechnology, and biochemistry》2016,80(9):1836-1842
Two kinds of oligosaccharides, N-acetylraffinosamine (RafNAc) and N-acetylplanteosamine (PlaNAc), were synthesized from N-acetylsucrosamine and melibiose using the transgalactosylation activity of Aspergillus niger α-galactosidase. RafNAc and PlaNAc are novel trisaccharides in which d-glucopyranose residues in raffinose (Raf) and planteose are replaced with N-acetyl-d-glucosamine. These trisaccharides were more stable in acidic solution than Raf. RafNAc was hydrolyzed more rapidly than Raf by α-galactosidase of green coffee bean. In contrast, RafNAc was not hydrolyzed by Saccharomyces cerevisiae invertase, although Raf was hydrolyzed well by this enzyme. These results indicate that the physicochemical properties and steric structure of RafNAc differ considerably from those of Raf. 相似文献
376.
Rhesus monkey TRIM5alpha restricts HIV-1 production through rapid degradation of viral Gag polyproteins 总被引:4,自引:0,他引:4
Mammalian cells have developed diverse strategies to restrict retroviral infection. Retroviruses have therefore evolved to counteract such restriction factors, in order to colonize their hosts. Tripartite motif-containing 5 isoform-alpha (TRIM5alpha) protein from rhesus monkey (TRIM5alpharh) restricts human immunodeficiency virus type 1 (HIV-1) infection at a postentry, preintegration stage in the viral life cycle, by recognizing the incoming capsid and promoting its premature disassembly. TRIM5alpha comprises an RBCC (RING, B-box 2 and coiled-coil motifs) domain and a B30.2(SPRY) domain. Sequences in the B30.2(SPRY) domain dictate the potency and specificity of the restriction. As TRIM5alpharh targets incoming mature HIV-1 capsid, but not precursor Gag, it was assumed that TRIM5alpharh did not affect HIV-1 production. Here we provide evidence that TRIM5alpharh, but not its human ortholog (TRIM5alphahu), blocks HIV-1 production through rapid degradation of HIV-1 Gag polyproteins. The specificity for this restriction is determined by sequences in the RBCC domain. Our observations suggest that TRIM5alpharh interacts with HIV-1 Gag during or before Gag assembly through a mechanism distinct from the well-characterized postentry restriction. This finding demonstrates a cellular factor blocking HIV-1 production by actively degrading a viral protein. Further understanding of this previously unknown restriction mechanism may reveal new targets for future anti-HIV-1 therapy. 相似文献
377.
K Jarukamjorn T Sakuma J Miyaura N Nemoto 《Archives of biochemistry and biophysics》1999,369(1):89-99
The effect of the synthetic glucocorticoid, dexamethasone, and phenobarbital upon the expression of Cyp2b9 and Cyp2b10, major CYP2B subfamilies in the mouse, was differentiated in C57BL/6 mouse liver and hepatocytes in primary culture. Overall expression was higher in the untreated female liver than in the male liver. More Cyp2b9 than Cyp2b10 mRNA was present in the female liver, whereas the level of Cyp2b10 was higher in the male. Phenobarbital increased Cyp2b10 expression more than did Cyp2b9 in both sexes. Treatment with dexamethasone markedly induced Cyp2b10 expression dose dependently, but simultaneously suppressed Cyp2b9 in both sexes. Evidence of this was obtained both in vivo and in hepatocyte culture. Furthermore, the existence of at least two unknown species of CYP2B, whose expressions were either increased or decreased by dexamethasone was suggested. Adrenalectomy increased the expression of Cyp2b9 and Cyp2b10 mRNAs, especially that of Cyp2b9 in the male liver. In addition, the expression of one unknown species which was constitutively suppressed increased in adrenalectomized male mice. That the treatment of dexamethasone or adrenalectomy altered the expression of CYP2B subfamilies suggests that endogenous glucocorticoid hormone plays a basic role in the constitutive expression of cytochrome P450. Furthermore, the sex-related difference in the expression of Cyp2b9 and Cyp2b10 suggests that sex-dependent secretion of endogeneous modulating factors is involved in the regulatory pathway. 相似文献
378.
Changes in the immunoreactivity of pituitary luteinizing hormone (LH) cells and in their fine structure were studied in 4-day-cyclic female rats along with the radioimmunoassay of pituitary and serum LH. Pituitary LH increased during diestrus (DE) and in early proestrus (PE) to a maximal level at noon of PE, followed by a marked decrease by 2100 h PE. Serum LH stayed at low levels in estrus (E) and in DE, while they displayed a significant increase at PE. Light microscopic immunocytochemistry distinguished intensely and weakly stained cells using rat LH beta antiserum. The populations of intensely stained cells were 80% at PE, 30% at E and 75% at DE. This suggests that all of the LH cells do not secrete LH synchronously on the afternoon of PE. Immunoreactivity of LH cells was related to the amount of secretory granules stored in the cells as determined by the superimposition technique. Analysis of the LH storage site by the protein A-gold method confirmed that the small secretory granules, which accumulated in LH cells at DE or PE, certainly contain LH. At least two LH cell types were distinguished: one is the oval or polygonal cell with flattened rER numerous mitochondria, abundant small secretory granules (about 200 nm), a well developed Golgi complex, and a round nucleus. The other has similar structural characteristics along with large secretory granules which are more than 300 nm in diameter. At noon of PE almost all of the LH cells were the first type while the second ones were mainly found at DE or E. The relationship of these LH cell types of the male gonadotrophs is discussed. 相似文献
379.
trans activation of the latent Epstein-Barr virus (EBV) genome after transfection of the EBV DNA fragment. 总被引:56,自引:37,他引:19
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Transfection of Epstein-Barr virus (EBV)-nonproducer Raji cells with the BamHI Z fragment of EBV DNA induced antigens that were detected with human antiserum against EBV-specific early antigens. Northern blot analysis of transfected cells revealed that one intense RNA band hybridized with the BamHI H and F fragments but not with the BamHI Z fragment. Cooperation between the BamHI H, F, and BamHI Z regions was also confirmed in baby hamster kidney cells that were cotransfected with both fragments. These results indicate that the transfected BamHI Z fragment of EBV DNA induces a trans-acting factor which activates the gene expression of the BamHI H and F region and that the BamHI Z region possibly plays an important role in the latency of EBV. 相似文献
380.
M Shinada M Azuma H Kawai K Sazaki I Yoshida T Yoshida T Suzutani T Sakuma 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1986,181(2):205-210
The effects of glycyrrhizin, a component of licorice (Glycyrrhiza glabra) roots, on the production of interferon-gamma in human peripheral lymphocyte-macrophage cultures by concanavalin A (Con A) was examined. Interferon-gamma production in normal lymphocyte-macrophage cultures treated with 10 to 100 micrograms/ml of glycyrrhizin at 37 degrees C for 12 hr or longer, and then treated with 10 micrograms/ml of Con A, was enhanced four to eight times compared to control cell cultures. Lymphocyte-macrophage cultures treated with 10 to 100 micrograms/ml of glycyrrhizin alone did not produce interferon. No significant difference in the adsorption of [3H]Con A to glycyrrhizin-treated and control lymphocyte-macrophage cultures was found, but RNA and protein synthesis of the treated lymphocytes was increased compared to control cells; DNA synthesis, however, was reduced. Collaboration between enriched T-lymphocytes and macrophages, both treated with glycyrrhizin, was needed for the enhancement of interferon-gamma production. A smaller increase in interferon production was also observed in the glycyrrhizin-treated peripheral lymphocyte-macrophage cultures derived from an asymptomatic carrier of hepatitis B virus, in response to Con A and surface antigen of hepatitis B virus. 相似文献