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991.
Daikichi Nishimura Akira Hasegawa Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(10):1767-1772
The condensation reaction of 3-acetamido-2,4,6-tri-O-benzyl-3-deoxy-α-d-glucopyranosyl chloride, 6-acetamido-2,3,4-tri-O-benzyl-6-deoxy-d-glucopyranosyl chloride and 2,3,4,6-tetra-O-benzyl-α-d-glucopyranosyl chloride were performed by a modified Königs-Knorr method. The rapid conversion of the benzyl halogeno derivative of 3-acetamido-3-deoxy-d-glucose to a stable intermediate caused a poor yield in the glucoside formation with complex aglycons at the presence of dioxane. For the benzyl halogeno derivative of 6-acetamido-6-deoxy-d-glucose, the C-6 acetamido group was favorable to the α-glucoside formation by its anchimeric assistance. A favorable effect of dioxane was observed for the α-glucoside formation of benzyl halogeno derivative of d-glucose. 相似文献
992.
Keiji Tanaka Makoto Kiso Masanori Yoshida Norio Kurihara Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(1):229-237
Two diastereomers of 1,2,3,4,5-pentachlorocyclohexane and two diastereomers of tetrachloromonomethoxycyclohexane were synthesized stepwise from diastereomers of 3,4,5-trichlorocyclohexene, which had been derived from the dl-(36/45)-, dl-(34/56)- and (346/5)-isomers of 3,4,5,6-tetrachlorocyclohexenen (α-, β- and γ-BTC, respectively) by selective reduction with LiAlH4. The configurations of all the products and intermediary trichlorocyclohexene isomers were determined by PMR studies. 相似文献
993.
In the presentstudy, we examined the ability of adenosine 3',5'-cyclicmonophosphate (cAMP) to reduce elevated levels of cytosolicCa2+ concentration([Ca2+]i)in pancreatic -cells.[Ca2+]iand reduced pyridine nucleotide, NAD(P)H, were measured in rat single-cells by fura 2 and autofluorescence microfluorometry. Sustained[Ca2+]ielevation, induced by high KCl (25 mM) at a basal glucose concentration (2.8 mM), was substantially reduced by cAMP-increasing agents, dibutyryl cAMP (DBcAMP, 5 mM), an adenylyl cyclase activatorforskolin (10 µM), and an incretin glucagon-likepeptide-1-(7-36) amide (109 M), as well as byglucose (16.7 mM). The[Ca2+]i-reducingeffects of cAMP were greater at elevated glucose (8.3-16.7 mM)than at basal glucose (2.8 mM). An inhibitor of protein kinase A (PKA),H-89, counteracted[Ca2+]i-reducingeffects of cAMP but not those of glucose. Okadaic acid, a phosphataseinhibitor, at 10-100 nM also reduced sustained [Ca2+]ielevation in a concentration-dependent manner. Glucose, but not DBcAMP,increased NAD(P)H in -cells.[Ca2+]i-reducingeffects of cAMP were inhibited by 0.3 µM thapsigargin, an inhibitorof the endoplasmic reticulum (ER)Ca2+ pump. In contrast,[Ca2+]i-reducingeffects of cAMP were not altered by ryanodine, an ERCa2+-release inhibitor,Na+-free conditions, or diazoxide,an ATP-sensitive K+ channelopener. In conclusion, the cAMP-PKA pathway reduces[Ca2+]ielevation by sequestering Ca2+ inthapsigargin-sensitive stores. This process does not involve, but ispotentiated by, activation of -cell metabolism. Together with theknown[Ca2+]i-increasingaction of cAMP, our results reveal dual regulation of -cell[Ca2+]iby the cAMP-signaling pathway and by a physiological incretin. 相似文献
994.
Shigenobu Yoshida Motoo Koitabashi Dai Yaginuma Masato Anzai Minoru Fukuda 《Journal of Phytopathology》2019,167(11-12):679-685
The potential of the active ingredient of a commercial bioinsecticide, XenTari® (Bacillus thuringiensis [BT] serovar aizawai strain ABTS‐1857), to suppress gray mold in tomato plants was elucidated. First, a suspension of the active ingredient of XenTari® and a liquid culture of the bacterial strain as BT inocula were sprayed onto detached leaves or drenched into pots of tomato seedlings, and then, propagules of the gray mold fungus, Botrytis cinerea, were inoculated onto the leaves. The gray mold disease was significantly suppressed when rhizospheres were drenched with either inoculum, but not when inocula were sprayed onto detached leaves of seedlings. Both BT inocula were verified not to directly inhibit the mycelial growth of B. cinerea based on in vitro culture plate assays. Additionally, real‐time RT‐PCR analysis verified that the active ingredient increased the expression levels of defence‐related genes, such as PR‐1(P6) and P4, in the leaves of tomato seedlings. These results suggest that the active ingredient has the potential to suppress gray mold disease in tomato, not through direct antagonistic interactions with B. cinerea, but rather through systemic activation of the plant defence system by increased expression of several defence‐related genes. 相似文献
995.
Mitsuru Yasui Takehiko Kikuchi Masahiro Ogawa Yoshihisa Otaka Minoru Tsuchitani Hiroshi Iwata 《Bioelectromagnetics》1997,18(8):531-540
Male and female F344 rats, 48 per exposure group, were sham exposed (Group A) or exposed to 0.5 (Group B) and 5 mT (Group C) magnetic fields for two years. Animals were exposed from 5–109 weeks of age in SPF conditions according to the OECD test guideline No. 451. Average exposure was 22.6 hr/day. No significant differences in body weight and food consumption were observed between the sham and exposed groups. At the end of the exposure period, survival rates of the male rats were 73, 83, and 79%, and those of the females, 77, 79, and 75% for Groups A, B, and C, respectively, with no significant differences between groups. Differential counts of leukocytes were measured at the 52nd, 78th, and 104th weeks of exposure and no significant differences were observed between the exposure groups. All survivors were euthanized on schedule, and all the organs and tissues suspected of tumoral lesions were examined histopathologically. Incidences of mononuclear cell leukemia in the male and the female rats were 5, 4, 4 and 8, 6, 7 for Groups A, B and C, respectively; incidences of malignant lymphoma in the female rats were 0, 1 and 1. Neither significant increases nor acceleration of incidence of leukemia were observed. Incidences of brain and intracranial tumors did not increase in the exposed groups. Incidences of both benign and malignant neoplasms showed no significant difference between the exposed and sham exposed groups with one exception: fibroma of the subcutis in the male rats, which was considered not to be a statistically significant when evaluated with respect to the historical control data in our laboratory. Bioelectromagnetics 18:531–540, 1997. © Wiley-Liss, Inc. 相似文献
996.
997.
998.
Hiroyuki Yamamoto Rina Okada Kazuaki Iguchi Satoshi Ohno Takashi Yokogawa Kazuya Nishikawa Keiko Unno Minoru Hoshino Atsushi Takeda 《Biochemical and biophysical research communications》2013,430(3):999-1004
Progalanin is released from the small cell lung carcinoma line SBC-3A and converted to its active form by plasmin. To elucidate the role of progalanin activation in the extracellular compartment, matrix metalloproteinase (MMP) activity was studied in SBC-3A cells treated with progalanin siRNA, and angiogenesis was measured in tumor tissue originating from SBC-3A cell transplantation into mice. Progalanin siRNA caused downregulation of progalanin expression for approximately 8 days. MMP activity and angiogenesis were reduced in tumors induced by transplantation of progalanin siRNA-treated SBC-3A cells. In contrast, MMP-9 and MMP-2 activity and angiogenesis increased in tumors originating from progalanin siRNA-treated SBC-3A cells in the presence of galanin and progalanin. Furthermore, injection of tranexamic acid, a plasmin inhibitor, more markedly reduced MMP-9 and MMP-2 activity and angiogenesis in tumors originating from progalanin siRNA-treated SBC-3A cells and in tumor tissue originating from progalanin siRNA-treated SBC-3A cells in the presence of progalanin. The reduction of MMP-9 and MMP-2 activity with tranexamic acid was restored by galanin, but not by progalanin. Moreover, tranexamic acid reduced angiogenesis in control siRNA-treated SBC-3A cells. These results suggest that the activation of progalanin by plasmin in the extracellular compartment was involved in MMP-9 and MMP-2 activation and in angiogenesis in tumor tissue. 相似文献
999.
Body fat mass reduction and up-regulation of uncoupling protein by novel lipolysis-promoting plant extract 下载免费PDF全文
Shinobu Mori Mayumi Satou Satoshi Kanazawa Naonobu Yoshizuka Tadashi Hase Ichiro Tokimitsu Yoshinori Takema Yoshinori Nishizawa Toshihiko Yada 《International journal of biological sciences》2009,5(4):311-318
We have found natural products exhibiting lipolysis-promoting activity in subcutaneous adipocytes, which are less sensitive to hormones than visceral adipocytes. The activities and a action mechanisms of a novel plant extract of Cirsium oligophyllum (CE) were investigated in isolated adipocytes from rat subcutaneous fat, and its fat-reducing effects by peroral administration and topical application were evaluated in vivo. CE-induced lipolysis was synergistically enhanced by caffeine, a phosphodiesterase inhibitor, and was reduced by propranolol, a β adrenergic antagonist. The peroral administration of 10% CE solution to Wistar rats for 32 days reduced body weight gain, subcutaneous, and visceral fat weights by 6.6, 26.2, and 3.0%, respectively, as compared to the control group. By the topical application of 2% of this extract to rats for 7 days, weight of subcutaneous fat in the treated skin was reduced by 23.2%. This fat mass reduction was accompanied by the up-regulation of uncoupling protein 1 (UCP), a principal thermogenic mitochondrial molecule related to energy dissipating, in subcutaneous fat and UCP3 in skin except for the fat layer. These results indicate that CE promotes lipolysis via a mechanism involving the β adrenergic receptor, and affects the body fat mass. This fat reduction may be partially due to UCP up-regulation in the skin including subcutaneous fat. This is the first report showing that repeated lipolysis promotion through CE administration may be beneficial for the systematic suppression of body fat accumulation or the control of fat distribution in obesity. 相似文献
1000.
Yoshio Matsuda Hidehito Kato Ken'ichi Imanishi Minoru Mitani Hiroaki Ohta Takehiko Uchiyama 《Microbiology and immunology》2010,54(1):38-45
The aim of this study was to determine the percentage of CD45RO+ T cells in umbilical cord blood from neonates born at less than 37 weeks of gestation. Fifty-nine patients were enrolled in this study, including 49 with preterm and 10 with term deliveries. Preterm deliveries were divided into two categories; spontaneous (Group A, n = 31) and indicated (Group B, n = 18). Perinatal infection was categorized as C-CAM, H-CAM and neonatal infection. The percentage of CD45RO+ T cells in the umbilical cord was assessed using flow cytometry. IL-6 was measured using ELISA. In Group A, the percentage of CD45RO+ T cells and concentrations of IL-6 in patients with perinatal infection ( n = 18) were significantly higher than in those without perinatal infection ( n = 13). A significant correlation between percentage of CD45RO+ T cells and IL-6 concentrations was observed in the cord blood ( r = 0.62, P = 0.001). In Group B, pink–tinged amniotic fluid was observed in seven cases. In these cases, an increase in the percentage of CD45RO+ T cells (>10%) was noted. In the cases without perinatal infection, which included all those delivered at term ( n = 32), no correlation was observed between the percentage of CD45RO+ T cells and gestational age at delivery ( r =−0.139, P = 0.448). We concluded that a high percentage of CD45RO+ cord blood T cells is observed not only in perinatal infection, but also in the presence of abnormal perinatal events such as maternal bleeding in preterm gestation. 相似文献