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91.
Nobutoshi Baba Hiroyuki Kawami Yukio Sato Takahiro Takayama Tetsuya Toge 《Biotherapy》1991,3(4):359-364
The enhancement of antitumor activities of the tumoricidal soluble factor (SF) from a streptococcal preparation (OK-432)-activated macrophages by the pretreatment with a protein-bound polysaccharide (PSK) was investigated in tumor-bearing mice.Two-step stimulations with OK-432 atin vivo priming andin vitro eliciting were required for the production of the tumoricidal SF by macrophages, and the tumoricidal activity of the SF apparently correlated with the uptake of OK-432 by macrophages at priming phase.Tumoricidal activity of the SF from OK-432-activated macrophages in proteose-peptone (P-P)-pretreated mice significantly decreased with the development of the tumor, whereas in PSK-pretreated mice did not. Pretreatment of tumor-bearing mice with PSK saved a decrease in the macrophages carrying Iak or asialo GM1 antigens and an increase in wheat germ agglutinin (WGA) receptors. Furthermore, the uptake of OK-432 by macrophages at priming phase was enhanced. The tumoricidal activity of the SF from OK-432-activated macrophages was augmented.Thus, PSK may restore the depressed functions of macrophages, and the combination therapy with PSK and OK-432 may be effective to enhance the production of tumoricidal SF in tumor-bearing mice. 相似文献
92.
T Baba A Jacq E Brickman J Beckwith T Taura C Ueguchi Y Akiyama K Ito 《Journal of bacteriology》1990,172(12):7005-7010
Mutations which cause poor growth at a low temperature, which affect aspects of protein secretion, and which map in or around secY (prlA) were characterized. The prlA1012 mutant, previously shown to suppress a secA mutation, proved to have a wild-type secY gene, indicating that this mutation cannot be taken as genetic evidence for the secA-secY interaction. Two cold-sensitive mutants, the secY39 and secY40 mutants, which had been selected by their ability to enhance secA expression, contained single-amino-acid alterations in the same cytoplasmic domain of the SecY protein. Protein export in vivo was partially slowed down by the secY39 mutation at 37 to 39 degrees C, and the retardation was immediately and strikingly enhanced upon exposure to nonpermissive temperatures (15 to 23 degrees C). The rate of posttranslational translocation of the precursor to the OmpA protein (pro-OmpA protein) into wild-type membrane vesicles in vitro was only slightly affected by reaction temperatures ranging from 37 to 15 degrees C, and about 65% of OmpA was eventually sequestered at both temperatures. Membrane vesicles from the secY39 mutant were much less active in supporting pro-OmpA translocation even at 37 degrees C, at which about 20% sequestration was attained. At 15 degrees C, the activity of the mutant membrane decreased further. The rapid temperature response in vivo and the impaired in vitro translocation activity at low temperatures with the secY39 mutant support the notion that SecY, a membrane-embedded secretion factor, participates in protein translocation across the bacterial cytoplasmic membrane. 相似文献
93.
M Ito M Baba S Mori K Hirabayashi A Sato S Shigeta E De Clercq 《Biochemical and biophysical research communications》1990,166(3):1095-1101
Tumor necrosis factor alpha (TNF-alpha) completely reverses the activity of azidothymidine (AZT) against human immunodeficiency virus type 1 (HIV-1) in MOLT-4 cell cultures. The 50% effective concentration of AZT, required to protect MOLT-4 cells against the cytopathic effect of HIV-1, increased from 5.8 nM in the absence of TNF-alpha to greater than 125 microM in the presence of TNF-alpha (100 U/ml). TNF-alpha also antagonized the anti-HIV-1 activity of dideoxycytidine but did not markedly affect the anti-HIV-1 activity of dextran sulfate. The intracellular phosphorylation pattern of AZT was not changed upon the presence of TNF-alpha. 相似文献
94.
Takeshi Shimizu Hiroaki Kinoh Masaaki Yamaguchi Norio Suzuki 《Development, growth & differentiation》1990,32(5):473-487
A sialoglycoprotein and a fucose sulfate glycoconjugate (FSG) were purified from egg jelly of the sea urchin Hemicentrotus pulcherrimus . Sialoglycoprotein which consisted of sialic acid (90%, w/w) and protein (10%, w/w) did not cause induction of the acrosome reaction and sperm isoagglutination. FSG which contained one mol sulfate/mol fucose possessed 2.0 times protein to fucose by weight. The proteins in intact FSG were separated to two major (258 kDa and 237 kDa) and one minor (120 kDa) proteins by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) in the presence of 2-mercaptoethanol (2-ME) while the proteins could not be separated by HPLC in the presence of 0.1% SDS or SDS-PAGE without 2-ME. However, after carboxymethylation of FSG, two major (260 kDa and 240 kDa) proteins and two minor (140 kDa and 135 kDa) proteins were separated from the fucose sulfate moiety by HPLC in the presence of 0.1% SDS or SDS-PAGE without 2-ME. When FSG was first carboxymethylated with non-radioactive iodoacetic acid and then reduced with 2-ME and finally carboxymethylated with 14 C-iodoacetic acid, the most of radioactivity was detected in 140 kDa and 135 kDa proteins. Carboxymethylted-FSG was less potent than intact FSG in induction of the acrosome reaction. Fucoidan, a fucose sulfate polymer, did not induce the acrosome reaction. 相似文献
95.
96.
Four tests for antibody to varicella-zoster (V-Z) virus were compared; these were tests of complement fixation (CF), neutralization (NT), fluorescent antibody to membrane antigen (FAMA) and immune adherence hemagglutination (IAHA). Fifty-two sera from patients with varicella and zoster and from recipients of live varicella vaccine were examined by the 4 tests. The CF test was least sensitive, but the antibody titers by the NT, FAMA and IAHA tests were roughly comparable. The IAHA test was the simplest and fastest to perform, and appeared suitable for routine serological assay to V-Z virus. The correlation between the IAHA antibody titer and susceptibility of individuals to clinical varicella was investigated retrospectively using sera obtained during 2 outbreaks of varicella in an institution for children, where all the unvaccinated children had developed varicella symptoms. Most of the 25 pre-exposure sera from unvaccinated children examined by the IAHA test had tiers of less than 1:2. In contrast, all the 23 sera from vaccinated children who did not develop varicella had detectable antibody titers of 1:2 to 1:64. These results indicate that the IAHA titer reflects the susceptibility or resistance of individuals to clinical varicella. 相似文献
97.
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99.
A case of hypoglycemic coma after alcohol ingestion was observed in a chronic alcoholic. Upon close examination isolated corticotrophin-deficiency was found. It is suggested that ethanol-induced hypoglycemia may be consistent with dysfunction of mitochondria in hepatic cells and that there may be disorder of the hypothalamus in the chronic drinker. 相似文献
100.
The rates of the utilization of glucose and mannose in Schizosaccharomycespombe were determined using glucose-grown cells. The rate ofaerobic fermentation in the medium containing glucose was notaffected by the addition of mannose. In contrast, CO2 evolutionin the mannose medium was greatly enhanced by the addition ofglucose, showing nearly the same rate as the glucose medium.The rate of glucose consumption was much higher than that ofmannose. In a medium containing both sugars, the rates of consumptionof glucose and mannose interfered with each other, the mannoseconsumption rate being more seriously affected by glucose. Intracellularaccumulation of the reducing sugar from the mannose containingmedium proceeded much more rapidly and reached a higher levelthan with the glucose medium. However, trehalose accumulatedat a much higher rate with the glucose medium. Consequently,the net increase in cellular carbohydrates, as calculated fromthe amount of reducing sugar and trehalose, proceeded much morerapidly in the glucose medium. We concluded that the differencein the rates of utilization of glucose and mannose might bedue to the difference in the rates of uptake of both sugars.
1Present adress: Department of Biology, Faculty of Science,Osaka City University, Sumiyoshiku, Osaka 558. To whom reprintrequests should be adressed. (Received June 24, 1975; ) 相似文献