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91.
A mouse representing a new hereditary cataract strain was found in a mouse colony and a new line was established strain CSM. These mice were investigated genetically, histologically and biochemically. The results suggested that this cataract was apparently inherited through two recessive autosomal genes. Histologically the denucleation process of lens fibers was abnormal and small vacuoles appeared in the equatorial region of the lens cortex at 12 days. Biochemically, insoluble protein and sodium increased in the lens with age. 相似文献
92.
A Umemoto S Grivas Z Yamaizumi S Sato T Sugimura 《Chemico-biological interactions》1988,68(1-2):57-69
In order to study the possible detoxification mechanisms of the carcinogenic arylamine, 2-amino-6-methyldipyrido[1,2-a: 3',2'-d]imidazole (Glu-P-1), the in vitro non-enzymatic reaction of 2-nitroso-6-methyldipyrido[1,2-a: 3',2'-d]imidazole (NO-Glu-P-1) with reduced glutathione (GSH) was examined at pH 7.4 under both aerobic and anaerobic conditions. Two GSH-arylamine adducts were isolated and found to contain the Glu-P-1 and GSH moieties in a 1:1 molar ratio via an N-S linkage. Their structures were assigned as sulfinamide (-NH-SO-) and N-hydroxy-sulfonamide (-N(OH)-SO2-) by their behaviour under acidic and basic conditions and by UV-VIS, 1H-NMR, infrared and mass spectrometries. Also, a N-hydroxy-sulfonamide adduct was produced when NO-Glu-P-1 and cysteine were reacted at pH 7.4. The N-hydroxy-sulfonamide structure is a new binding form between arylnitroso compounds and thiols. The formation of these adducts may also take place in vivo as a detoxification of toxic arylamines since GSH is abundant in organs such as liver or kidney. 相似文献
93.
In order to investigate whether endogenous GHRH and somatostatin were involved in the mechanism of the paradoxical GH rise after TRH injection, changes in serum GH and plasma GHRH were examined before and after TRH injection in 12 cancer patients and changes in serum TSH and GH were similarly studied in 76 cancer patients including 31 GH-responders and 45 GH-nonresponders to TRH. TRH stimulated GH secretions without altering the circulating GHRH concentration in 4 of the 12 cancer patients. There was neither a significant correlation between the increase from the basal to maximum GH and GHRH after TRH injection in the 12 cancer patients nor a reciprocal relationship between the increase in GH and TSH after TRH injection in the 76 cancer patients. These findings suggested that the paradoxical GH rise after TRH injection in cancer patients was exerted by its direct action at the pituitary level, and not mediated through the hypothalamus. 相似文献
94.
C Hamada N L Sato S Niimura A Kato N Fujisawa Y Maeda T Kumanishi H W Lee 《Jikken dobutsu》1986,35(1):1-9
An assay method for the infectivity of Hantaan virus, a causative agent of HFRS (hemorrhagic fever with renal syndrome), was developed by the use of IFA (immunofluorescent antibody technique). With the aid of this method, the growth characteristics of Hantaan virus, 76-118 strain, were followed in A549 cells. At a maximal MOI (multiplicity of infection) of 1.6 VAIU (viral antigen-inducing units) per cell, the conventionally available value, plateau level potencies of the viral antigen and virus infectivity were attained at eight and ten days postinfection, respectively, and most of the infective virus produced accumulated in the culture fluids of infected cells. When infections were defined with MOI values in terms of VAIU per cell, development of the viral antigen was highly consistent and followed a given pattern of kinetics. Based on these findings, a protocol for preparation of the viral antigen in IFA was presented, wherein spot culture and FBS treatment were emphasized as effective procedures to minimize non-specific staining. 相似文献
95.
Quantitation of the Myelin-Associated Glycoprotein in Human Nervous Tissue from Controls and Multiple Sclerosis Patients 总被引:3,自引:2,他引:1
David Johnson Shuzo Sato Richard H. Quarles Takashi Inuzuka Roscoe O. Brady Wallace W. Tourtellotte 《Journal of neurochemistry》1986,46(4):1086-1093
Myelin-associated glycoprotein (MAG) was measured by radioimmunoassay in the human CNS and peripheral nervous system (PNS). The level of MAG, expressed as ng/microgram of total protein, was approximately 20-fold higher in whole homogenates of cerebral white matter (4.7 +/- 0.60) than of peripheral nerve (0.12-0.28). MAG concentrations were only slightly higher in the isolated myelin fractions from these tissues: CNS myelin, 5.6 ng/microgram; PNS myelin, 0.37 ng/microgram. The levels of MAG were measured in nine plaques, periplaque regions, and areas of macroscopically normal-appearing white matter (NAWM) from six separate multiple sclerosis brains and compared with the levels of other myelin proteins in the same samples. MAG and other myelin proteins were reduced to very low levels in plaques. The levels of MAG and basic protein (BP) and the activity of 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP) in periplaque areas were significantly lower than those in control white matter, and MAG and BP levels were also significantly reduced in NAWM. In a periplaque region and NAWM from the most rapidly progressing case of multiple sclerosis examined, the MAG content was between 30 and 35% of the control level, whereas BP and PLP levels and CNP activity were between 50 and 85% of control values. The reduction of MAG content in periplaque regions from all nine multiple sclerosis plaques examined was significantly greater than the reductions of BP level and CNP activity. In NAWM samples, the mean reduction of MAG content was also greater than the reductions of BP level and CNP activity, but the difference was only statistically significant in comparison to CNP.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
96.
D Takatsuka H Mori S Noguchi Y Nishizawa B Sato K Matsumoto 《Journal of steroid biochemistry》1986,24(3):715-719
Homogenates of estrogen-responsive mouse Leydig cell tumors (T 124958-R and T 22137) or 28- and 120-day-old mouse testes were incubated with [3H]progesterone or [14C]4-androstene-3,17-dione in the presence of NADPH, and progesterone metabolism and enzyme activities were estimated. The growth of T 124958-R tumor transplanted in BALB/c mice was markedly stimulated by estrogenization of host mice, but the growth of T 22137 tumor was evidently suppressed by the estrogenization. The major C21-17-OH-steroids and C19-steroids formed from progesterone by both tumors and the testes of immature mice were 5 alpha-steroids, such as 3 alpha,17-dihydroxy-5 alpha-pregnan-20-one, 5 alpha-androstane-3,17-dione, androsterone, 3 beta-hydroxy-5 alpha-androstan-17-one and 5 alpha-androstane-3 alpha,17 beta-diol. In contrast, the major steroids formed by the testes of adult mice were testosterone and 4-androstene-3,17-dione, and no or little 5 alpha-steroids were produced. 5 alpha-Reductase activities in both tumor cells (40-50 nmol/l X 10(8) cells per h) were also found to be approx. 5-6 times higher than that in Leydig cells of adult mouse testes (8 nmol/l X 10(8) Leydig cells per h), though 17-hydroxylase activity was much higher in the Leydig cells of adult testes (730 nmol/l X 10(8) Leydig cells per h) than in both tumor cells (1-7 nmol/l X 10(8) cells per h). Furthermore, the presence of significant amounts of endogenous androsterone and/or 5 alpha-androstane-3 alpha,17 beta-diol was demonstrated in both tumors by radioimmunoassay. The present results demonstrate for the first time that C19-5 alpha-steroids are major C19-steroid products (immature type of testicular androgen production) in Leydig cell tumor lines. 相似文献
97.
Phosphoenolpyruvate carboxykinase of chicken liver cytosol was purified to homogeneity by procedures including affinity chromatography with GTP as a ligand. The purified enzyme showed a molecular weight of 68,000 on gel electrophoresis in the presence of dodecyl sulfate. Comparative studies on this enzyme and its isozyme purified from chicken liver mitochondria were performed. As regards amino acid composition, the cytosolic enzyme was quite different from the mitochondrial enzyme, but was rather similar to rat liver cytosolic phosphoenolpyruvate carboxykinase. Specific activities of the cytosolic enzyme were 30-100% higher than those of the mitochondrial enzyme for oxaloacetate-CO2 exchange, oxaloacetate decarboxylation, and phosphoenolpyruvate carboxylation reactions, though the relative rates of the activities were similar, decreasing in the order given. Apparent Michaelis constants for oxaloacetate in the oxaloacetate decarboxylation reaction were 11.6 and 17.9 microM for the cytosolic and the mitochondrial enzyme, respectively, but the values for GTP, GDP, phosphoenolpyruvate, and CO2 in the oxaloacetate decarboxylation and phosphoenolpyruvate carboxylation reactions were 1.3-2.2 times higher for the cytosolic enzyme than for the mitochondrial enzyme. Thus, the fundamental catalytic properties of the chicken liver phosphoenolpyruvate carboxykinase isozymes were rather similar, despite the marked difference in amino acid compositions. 相似文献
98.
OH-induced free radicals in purine nucleosides and their homopolymers: e.s.r. and spin-trapping with 2-methyl-2-nitrosopropane 总被引:1,自引:0,他引:1
M Kuwabara O Inanami F Sato 《International journal of radiation biology and related studies in physics, chemistry, and medicine》1986,49(5):829-844
Free radicals produced by X-irradiation of N2O-saturated aqueous solutions of purine nucleosides (2'-deoxyadenosine, adenosine, 2'-deoxyguanosine, 3'-deoxyadenosine, guanosine and inosine) and the corresponding homopolymers (poly A and poly I) have been investigated by the technique of spin-trapping and e.s.r. spectroscopy. 2-Methyl-2-nitrosopropane was used as a spin-trap. For 2'-deoxyadenosine and 2'-deoxyguanosine, the resulting spin-adducts were separated by Bio-Gel P-2 column chromatography and analysed by e.s.r. spectroscopy. For homopolymers, e.s.r. spectra were recorded at 50 degrees C after enzymatic digestion to obtain signals with narrower line width. The e.s.r. signal consisting of only a primary triplet without further splittings, which is consistent with assignment to the trapping of an H-abstraction radical at the C4' position of the sugar moiety, was observed in all cases. For 2'-deoxyguanosine an e.s.r. signal consisting of a secondary triplet was observed. Examinations using other spin-trapping reagents such as PBN, 4-PyOBN and DMPO provided no positive evidence supporting the proposal that this was due to an alpha-nitrogen. The e.s.r. signal consisting of a secondary doublet which further splits into a doublet was observed for 2'-deoxyadenosine, adenosine, 3'-deoxyguanosine, 2'-deoxyguanosine, and inosine, and tentatively associated with a radical centered in the sugar moiety. 相似文献
99.
Conservation of DNA sequences for plasmid-mediated citrate utilization within the enterobacteria. 总被引:2,自引:1,他引:1
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Southern blot DNA-DNA hybridization experiments with a cloned Cit+ DNA fragment as a probe showed that the plasmid-mediated Cit+ determinants from four Cit plasmids (R726, pOH3001, pOH3035, and pOH30221) were all homologous. Sequences homologous to the plasmid-borne Cit+ gene were also found in total bacterial DNA isolated from Salmonella paratyphi B, Salmonella enteritidis, Salmonella typhimurium LT-2, Citrobacter freundii, ATCC 8090, Citrobacter amalonaticus ATCC 25405, Klebsiella pneumoniae I and IID 977, and Enterobacter aerogenes ATCC 13048. The DNA digest from C. amalonaticus ATCC 25405 contained a 1.4-kilobase BamHI-HincII DNA fragment that was strongly homologous with and identical in size to the plasmid Cit+ probe. 相似文献
100.
A new method for solid-state ethanol fermentation (the SSEF system) was experimented on for the ethanol production from solid starchy materials, where a packedbed-type fermentor was used. Both cultivation of Aspergillus saitoi and enrichment of a saccharifying enzyme were effective for hydrolysis of the starch. Ethanol production was set in by a form of parallel fermentation using a respiration-deficient mutant of Saccharomyces cerevisiae. Produced ethanol was simultaneously stripped by circulating inert gas and separated in a condenser. Average ethanol concentration in the condensate was over 200 g/L, and over 90% of produced ethanol was recovered from the packed bed during 15 or 16 days of stripping. The fermentation efficiency was about 80%, which was evaluated much higher than those of conventional solid-state fermentations. The residue had lesser volume and a higher solids content compared with the distillery wastewaters of conventional liquid-state fermentations. This means an advantage for the treatment and the effective conversion of the residue into fetilizers or animal feeds. 相似文献