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991.
Haruaki Kageyama Asako Suga Misato Kashiba Jun Oka Toshimasa Osaka Takayuki Kashiwa Tsutomu Hirano Kiyomitsu Nemoto Yoshio Namba Daniel Ricquier Jean-Paul Giacobino Shuji Inoue 《FEBS letters》1998,440(3)
Streptozotocin (STZ)-induced diabetic animals are vulnerable to cold stress. Uncoupling proteins (UCPs) play an important role in regulating thermogenesis. We investigated the gene expressions of UCPs in brown adipose tissue (BAT), white adipose tissue (WAT), liver and gastrocnemius muscle of STZ-diabetic rats using Northern blot. UCP-1, -2 and -3 mRNA expressions in BAT were all remarkably lower in STZ-diabetic rats than those in control rats. Both UCP-2 and -3 gene expressions in gastrocnemius muscle were substantially elevated in STZ-diabetic rats and insulin treatment restored UCP gene expressions to normal levels. These results suggest that in STZ-diabetic rats, the overexpression of UCP-2 and UCP-3 in skeletal muscle provides a defense against hypothermogenesis caused by decreased UCPs in BAT. 相似文献
992.
Nobuo Kido Tsuyoshi Sugiyama Takashi Yokochi Hidemitsu Kobayashi & Yoshio Okawa 《Molecular microbiology》1998,27(6):1213-1221
WbdA (previously MtfA) is one of the mannosyltransferases encoded within the Escherichia coli O9a wb* gene cluster. It is composed of two domains of similar size, connected by an α-helix chain. Elimination of the C-terminal half by transposon insertion or gene deletion caused synthesis of an altered structural O-polysaccharide consisting only of α-1,2-linked mannose. O9a polysaccharide synthesis was restored by the C-terminal half of WbdA in trans . No membrane incorporation of mannose from GDP mannose was observed in a strain carrying only the gene for truncated WbdA. For mannose incorporation, it was necessary to introduce both wbdB and wbdC genes into the strain. Therefore, it is likely that the N-terminal half of truncated WbdA synthesizes the altered O-polysaccharide together with other mannosyltransferases which participate in the initial reactions of the O9a polysaccharide synthesis. Both N- and C-terminal domains of WbdA are required for the synthesis of the complete E. coli O9a polysaccharide. The chi sequence location between the two domains and homology plot analyses of the wbdA and the WbdA protein suggested that the wbdA gene might have arisen by fusion of two independent genes. 相似文献
993.
The effects of trivalent metal ions such as lanthanoid (La , Ce, Nd , Sm , Gd , Er , Yb , Lu ) and Al ions on the morphological change and proliferation of B16 melanoma cells in culture are discussed. These metal ions induced morphological transformations and decreased growth rates at doses of 1 mM. B16 melanoma cells treated with La , Ce , Nd , Sm , and Gd showed polyhedrical spreading. Elongation of axones was dependent on the metal ions. B16 melanoma cells treated with Er , Yb , Lu , and Al showed a long slender shape. Growth rates of melanoma cells in the presence of 1 mM of metal ions (La , Ce , Nd , Sm , Gd , Yb , Al ) were significantly lower than that of control cells. Measurements of cell cycle indicated that the metal ions arrested the transitions from G /G to S state. © Rapid Science 1998 相似文献
994.
Masaharu Inouye Yoshio Takada Naoki Muto Teruhiko Beppu Sueharu Horinouchi 《Molecular & general genetics : MGG》1994,245(4):456-464
A 29 kb shuttle cosmid vector, pTYS507, was constructed from a cryptic Micromonospora griseorubida plasmid and the Escherichia coli cosmid pJB8. Subcloning of mycinamicin II biosysnthesis genes in pTYS507 led to the identification of a DNA region that could complement a mutant of M. griseorubida that lacked both hydroxylase and epoxidase activities. Nucleotide sequence and mutational analysis suggested that a single P-450-like protein catalyzes both reactions. 相似文献
995.
Shimada Toshio Arakawa Eiji Itoh Kenichiro Okitsu Tadayuki Matsushima Akiyoshi Asai Yoshio Yamai Shiro Nakazato Tamotsu Nair G. Balakrish Albert M. John Takeda Yoshifumi 《Current microbiology》1994,28(3):175-178
Fifty-seven new O serogroups have been added to the existing serotyping scheme ofVibrio cholerae to extend the scheme from O84 to O140. Prominent new additions were serogroups O139 and O140. The reference strain of O139 was isolated from a patient from an epidemic of cholera-like diarrhea in Madras, Southern India. Serogroup O140 was assigned to a group ofV. cholerae strains which were tentatively named as the Hakata serogroup and which possessed the C (Inaba) factor but not the B (Ogawa) nor the A (major specific antigen of O1 serogroup ofV. cholerae). As all antisera against reference strains ofV. cholerae contained some amount of antibody to the rough (R) antigen, all diagnostic O antisera must be absorbed with the reference rough strain, CA385. 相似文献
996.
Yoshio Ichinose Masahiko Ehara Takeshi Honda Toshio Miwatani 《FEMS microbiology letters》1994,115(2-3):265-271
Abstract The effect on enterotoxicity of protease purified from Vibrio cholerae O1 was investigated by the inoculation of live vibrio cells into the protease-treated loops of the ileal loop model. Fluid accumulation ratios in the protease-treated loops were elevated in a dose-dependent manner by challenge with live vibrio cells byt not that with toxin. An enhancement effect of protease on enterotoxicity was observed in both serotypes of V. cholerae O1 and V. cholerae non-O1. It is suggested, therefore, that the enterotoxicity was enhanced by treatment with protease when live vibrio cells were inoculated into the ileal loops of rabbits. 相似文献
997.
Yukiko Shimizu Carol Yarborough Yoshio Osawa 《The Journal of steroid biochemistry and molecular biology》1993,44(4-6):651-656
In order to better understand the function of aromatase, we carried out kinetic analyses to asses the ability of natural estrogens, estrone (E1), estradiol (E2), 16-OHE1, and estriol (E3), to inhibit aromatization. Human placental microsomes (50 μg protein) were incubated for 5 min at 37°C with [1β-3H]testosterone (1.24 × 103 dpm 3H/ng, 35–150 nM) or [1β-3H,4-14C]androstenedione (3.05 × 103 dpm 3H/ng, 3H/14C = 19.3, 7–65 nM) as substrate in the presence of NADPH, with and without natural estrogens as putative inhibitors. Aromatase activity was assessed by tritium released to water from the 1β-position of the substrates. Natural estrogens showed competitive product inhibition against androgen aromatization. The Ki of E1, E2, 16-OHE1, and E3 for testosterone aromatization was 1.5, 2.2, 95, and 162 μM, respectively, where the Km of aromatase was 61.8 ± 2.0 nM (n = 5) for testosterone. The Ki of E1, E2, 16-OHE1, and E3 for androstenedione aromatization was 10.6, 5.5, 252, and 1182 μM, respectively, where the Km of aromatase was 35.4 ± 4.1 nM (n = 4) for androstenedione. These results show that estrogens inhibit the process of andrigen aromatization and indicate that natural estrogens regulate their own synthesis by the product inhibition mechanism in vivo. Since natural estrogens bind to the active site of human placental aromatase P-450 complex as competitive inhibitors, natural estrogens might be further metabolized by aromatase. This suggests that human placental estrogen 2-hydroxylase activity is catalyzed by the active site of aromatase cytochrome P-450 and also agrees with the fact that the level of catecholestrogens in maternal plasma increases during pregnancy. The relative affinities and concentration of androgens and estrogens would control estrogen and catecholestrogen biosynthesis by aromatase. 相似文献
998.
Norimichi Kan Keiichi Mise Masaki Nakanishi Takashi Okino Takehisa Harada You Ichinose Yoshio Moriguchi Tomoharu Sugie Li Li Masayuki Imamura 《Biotherapy》1993,6(4):303-309
Mice were injected in the foot pad with either 5×105 syngeneic plasmacytoma (MOPC104E) or fibrosarcoma cells (Meth A). Lymph nodes containing tumor cells were harvested 14 days later and cultured. In the presence of recombinant interleukin-2 (r-IL-2) predominantly tumor cells proliferated. Culture with T cell growth factor (TCGF) resulted in the growth of lymphoid cells. Concanavalin A (Con A) had only a modest effect on elimination of tumor cells in the culture. Tumor-infiltrating lymphocytes (TIL) prepared from the lymph nodes showed specific tumor-neutralizing activity when grown in the presence of TCGF. In vitro examination revealed that Meth A cells could not be lysed by TIL, while TIL from MOPC tumors showed tumor specific activity. This study may explain negative results in human trials with TIL induced by IL-2 alone.Abbreviations r
recombinant
- IL-2
interleukin-2
- TCGF
T cell growth factor
- TIL
tumor infiltrating lymphocytes
- Con A
concanavalin A
- HBSS
Hanks' balanced salt solution 相似文献
999.
Takehisa Harada Norimichi Kan Takashi Okino You Ichinose Yoshio Moriguchi Li Li Tomoharu Sugie Kazuhisa Ohgaki Masayuki Imamura 《Biotherapy》1993,7(2):91-99
This study shows that intraperitoneal injection of interleukin-1 (IL-1), followed by interleukin-2 (IL-2), can effectively eradicate murine ascitic tumor cells. This antitumor effect of IL-1 and IL-2 was abolished when administration of IL-2 preceded that of IL-1. Solid tumors inoculated subcutaneously (s.c.) into the back of mice were also sensitive to this combined i.p. therapy, indicating a systemically-operating antitumor mechanism. Splenocytes from tumor-bearing mice treated with IL-1 followed by IL-2 showed a strong tumor-neutralizing activity. The population responsible proved to be Lyt2.2 (CD8)-positive cells.Abbreviations IL
interleukin
- LAK
lymphokine activated killer
- LU
lytic unit
- MST
median survival time
- SE
sonicated tumor extract 相似文献
1000.
Keinosuke Okamoto Yoshio Fujii Noriko Akashi Shunji Hitotsubashi Hisao Kurazono Tadahiro Karasawa Yoshifumi Takeda 《Microbiology and immunology》1993,37(5):411-414
Stock strains of Eschericia coli isolated from patients with traveller's diarrhea were examined for production of heat-stable enterotoxin II (STII). Of 400 strains examined, 3 were found to produce STII. The nucleotide sequence of the STII gene of these human strains was shown to be identical to that of porcine strains. Cultured cells of these strains induced fluid accumulation in ligated mouse intestinal loops and the activity was neutralized by anti-STII antiserum. These results suggest that STII-produciing enterotoxigenic E. coli can cause human diarrhea. 相似文献