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1.
A simple method of estimating type-specific neutralizing antibody to type 2 herpes simplex virus (HSV-2) was devised with the use of the microneutralization system. Serially diluted serum was mixed in the well with a constant amount of type 1 virus (HSV-1), and after 3 days' incubation at 37 C, the plate was irradiated with ultraviolet light. The absorbing HSV-1 consisted of culture fluid plus an extract of infected Vero cells not especially concentrated. The well then received indicator HSV-1 or HSV-2, and after being left at 37 C for 1 hr a suspension of dispersed Vero cells was dropped into the wells, following our standard neutralization procedure. Preliminary tests with rabbit antisera showed that even a low level of HSV-2 antibody was detected by this method, unless an exceptionally high titer of HSV-1 antibody originally coexisted with the HSV-2 antibody. Sera from acutely infected persons testified to the specificity of the antibody so detected. It was revealed by means of the new technique that the rate of HSV-2 antibody was significantly higher in uterine cervical cancer patients than in control women. There was no correlation between the clinical stage of cervical cancer and the presence of HSV-2 antibody.  相似文献   
2.
Abstract Pseudomonas syringae cells were exposed to Cu2+ alone or in the precence of acetate, proline or cysteine, at concentrations that reduced free Cu2+ to 1/10 of the total copper. Ligand concentrations (designated as isoeffective) were determined experimentally using a Cu2+-selective electrode and confirmed by computer calculations using published stability constants. Exposure of P. syringae cells to Cu2+ alone resulted in rapid and pronounced cell death, and binding of most of the copper in solution. The addition of acetate, proline or cysteine, a few minutes after Cu2+ treatment, resulted in a significant reduction in cell death, and in the amount of copper bound to the cells. For short exposures to Cu2+, cysteine was more effective than acetate or proline, but after 60 min of treatment, similar results were observed with these ligands. The addition of ligands before Cu2+ resulted in even more reduced copper toxicity. The results showed that, at isoeffective concentrations, weak and moderate copper-ligands can effectively antagonize copper toxicity, and that this protective effect does not require previously equilibrated copper-ligand solutions and is not very dependent of the nature of the ligand.  相似文献   
3.
The effect of fish oil-derived omega-3 (omega-3) fatty acids on anaphylaxis, Arthus and delayed type hypersensitivity reactions in mice has been investigated. Mice on a normal chow diet were fed eicosapentaenoic acid and docosahexaenoic acid at a dose of 500 and 333 mg/kg/day, respectively, by a gastric tube over a period of 61 days. Control groups were given water, safflower oil or oleic acid. Anaphylactic and Arthus type reactions were induced in the mouse footpad using bovine serum albumin as an antigen. Carrageenin was utilized to produce a delayed type hypersensitivity reaction. The animals fed omega-3 fatty acids induced a more anaphylactic foodpad reaction. There was no significant effect of the diet on Arthus and delayed type hypersensitivity responses. There was no effect of the fish oil-supplemented diet on production of antibodies to bovine serum albumin. Synthesis of prostaglandin E2 by peritoneal macrophages was significantly inhibited in the animals fed omega-3 fatty acid-enriched fish oil, while leukotriene B4 production was not affected. These results suggest that a diet enriched in omega-3 fatty acids modulates production of arachidonic acid metabolites and this may influence anaphylaxis, but not Arthus and cellular mediated hypersensitivity responses.  相似文献   
4.
Axenically transformed primary sporocysts of Schistosoma mansoni (NMRI strain) were labeled with 125I in an effort to identify sporocyst proteins exposed at the tegumental surface. Using the 125I activating reagent, 1,3,4,6-tetrachloro-3 alpha,6 alpha-diphenylglycoluril, in conjunction with SDS-PAGE and autoradiography, up to 12 bands were radiolabeled out of 60 components visualized by silver staining. Labeled proteins ranged in apparent Mr from greater than 200 to less than 12 kDa. Pronase treatment of living sporocysts after radioiodination removed all labeled material, suggesting that only surface proteins were being iodinated. Western blot analysis employing 5 monoclonal antibodies (MAB's) to sporocyst surface antigens revealed a wide range of reactivities which produced banding patterns closely reflecting autoradiograms of identical samples. The concomitant removal by Pronase of immunoreactive and radiolabeled surface proteins with identical Mr in the range of 90-130 kDa suggests that epitopes recognized by these antibodies are associated with these higher molecular weight surface proteins. However, although Pronase removes all labeled surface proteins, substantial nonradiolabeled, immunoreactive material with Mr less than 90 kDa still remains on enzyme-treated parasites. This indicates that MAB-reactive epitopes, in addition to their occurrence with surface proteins, are also associated with either unlabeled, protease-resistant surface components or internal antigens. The immunohistochemical localization of antibody-reactive material in gland-like structures within sporocysts supports an internal source for nonradiolabeled, immunoreactive components. Finally, the periodate sensitivity of the epitopes recognized by all tested MAB's suggests that carbohydrate moieties may represent a common and extremely immunogenic constituent of the sporocyst surface.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
5.
The effect of forskolin on collagen production in osteoblasts was investigated by using clonal osteoblastic MC3T3-E1 cells cultured in a-minimum essential medium containing 0.1% bovine serum albumin. Forskolin increased the adenylate cyclase activity in membranes pelleted from homogenates of the cell line in a dose-dependent manner. The drug caused a 13-fold stimulation at 10(-4) M, indicating that the compound directly acts on adenylate cyclase, leading to an increase in the intracellular cAMP content of the cells. Collagen accumulation in the cultures was elevated by one-day treatment with 5 X 10(-5) M forskolin to about twice that in the controls. The stimulation was mainly due to an elevation in collagen synthesis but not to an inhibition of intracellular collagen degradation because forskolin dose-dependently increased collagen synthesis; it also significantly increased the amount of low-molecular-weight hydroxyproline found in the cultures. Cells treated with forskolin produced mainly type I collagen, as found in bone matrix in situ, with only small amounts of other types of collagen. Furthermore, forskolin time-dependently inhibited DNA synthesis in the cells, indicating that the increase in type I collagen synthesis by forskolin was not due to stimulated cell proliferation. These results suggest that cAMP is closely linked to the differentiation of osteoblasts in vitro.  相似文献   
6.
To elucidate the mechanisms underlying the dysfunctions of intestinal absorption induced by antitumor drugs, the effect of pretreatment with mitomycin C on sodium gradient-dependent D-glucose and L-alanine transports was studied in rat brush-border membrane vesicles. 24, 48, 96, or 120 h following a single intravenous injection of mitomycin C, brush-border membrane vesicles were prepared from rat small-intestines. The uptake of D-glucose and L-alanine was shown to be Na+ gradient-dependent even in the case of vesicles obtained from mitomycin C-treated rats, but uptake rates measured at 15 s and magnitude of overshooting effect in uptake of both solutes were decreased in vesicles maximally from 48 h mitomycin C-treated rats. The rate of D-glucose uptake calculated at 15 s recovered to the control level in vesicles prepared at 96 h and 120 h after mitomycin C-treatment, indicating that the effect of mitomycin C on Na+ gradient-dependent D-glucose transport would be fully reversible. Tracer exchange experiments under Na+ and D-glucose equilibrated conditions indicated that the Na+/D-glucose transporters were similarly operative in the vesicles from control and 48 h mitomycin C-treated rats. Rates of 22Na+ uptake measured at 15 s in vesicles from 48 h mitomycin C-treated rats, however, were increased. The increased permeability to Na+ might bring about a more rapid dissipation of the Na+ gradient in these vesicles and this would secondarily cause the decrease in Na+-dependent D-glucose uptake in vesicles from mitomycin C-treated rats.  相似文献   
7.
Summary A convenient and efficient method of NADPH production from NADP+ has been established using a glucose dehydrogenase system involving whole cells and immobilized cells of Gluconobacter suboxydans IFO 3172. Using airdried cells of the bacterium, the optimum conditions for NADPH production were examined, including the cell and glucose concentrations, NADP+ concentration, pH, buffer and reaction temperature. Under suitable conditions, the conversion ratio and the amount of NADPH accumulated reached about 100% and 73 mg/ml of the reaction mixture, respectively, after 1-h reaction. Intact cells of the bacterium also showed high NADPH production even in the reaction mixture without a surfactant. The addition of Triton X-100 to the reaction mixture and freeze-thawing treatment of intact cells enhanced the production. The NADPH production method was further improved by using cells of the bacterium immobilized by entrapment in a -carrageenan gel lattice. The immobilized cells had almost the same enzymatic properties as the air-dried cells. The conditions for the continuous production of NADPH with an immobilized cell column were also investigated. NADPH was produced in a good yield (about 95%) with this continuous process.  相似文献   
8.
The chromosomal gene for human phenylethanolamine N-methyltransferase (PNMT; EC 2.1.1.28) was isolated from a human genomic library using a cloned human PNMT cDNA as a probe, and the nucleotide sequence was determined. PNMT is encoded in a single gene which consists of three exons. We observed newly the presence of minor PNMT mRNA (type B) besides the major mRNA (type A) as reported previously (Kaneda et al., J. Biol. Chem. 263, 7672–7677, 1988) by Northern hybridization. Type B mRNA carries an approximately 700 nucleotide-long untranslated region in the 5′ terminus. This suggests that two types of mRNA are produced from a single gene through the use of two alternative promoters. A TATA-like sequence locates 30 base pair upstream from the cap site of type A mRNA. Upstream of the cap site, there are several sequences resembling Spl binding sites and glucocorticoid responsive elements, with the latter also found in the first intron.  相似文献   
9.
Pre- and postoperative intradermal administration of OK-432 enhanced the SU-PS skin reaction in patients with gastric cancer, but failed to prevent a fall in the NK activity induced by the operation.The change in NK activity was not associated with a change in the proportion of Leu 7-positive cells, but was related to Leu 11a-positive cells. Intradermal injection of OK-432 increased the proportion of Leu 7-positive cells in the patients in whom they accounted for less than 20% of lymphocyte population. The case was the same with Leu 11a-positive cells.Intravenous injection of OK-432 tended to increase suppressor-inducer T cells (CD4+2HA+ cells), B cells and Leu 7-positive cells. Particularly, the proportions of OK-M1-positive cells and MHC class II antigen-positive cells increased in all patients. Immunotherapy with OK-432 given intravenously at a dose of 0.1 KE appeared to be safe because no side effects were essentially observed.  相似文献   
10.
Among several detergents, a zwitterionic detergent, 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate (CHAPS), was found to be least cytotoxic for cultured mammalian cells. CHAPS improved the activity recovery and elution profile of crude and purified fibroblast growth factors (FGFs) during chromatographies. Diluted preparations of FGFs were stabilized by CHAPS against the loss during storage. Amino acid sequence analysis was not disturbed by CHAPS. CHAPS was removable by reversed-phase high-performance liquid chromatography. These results indicate that CHAPS is useful as a non-cytotoxic stabilizing agent in purification of various kinds of bioactive polypeptides.Abbreviations -MEM Alpha Modification of Eagle's Minimal essential medium - CHAPS 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate - CHAPSO 3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxy-1-propane sulfonate - CS Calf Serum - EGF Epidermal Growth Factor - FGF Fibroblast Growth Factor - HPLC High-Performance Liquid Chromatography - NGF Nerve Growth Factor - NOG 1-O-n-octyl--D-glucopyranoside - NP-40 Nonidet P-40 - PBS Phosphate-Buffered Saline - SB 12 3-(dodecylmethylammonio)-1-propane sulfonate - SDS Sodium Dodecyl Sulfate - TGF- and Transforming Growth Factor type and   相似文献   
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