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Biomedical subjects

M Ogata

Publications and source records attributed to M Ogata.

At least 397 records · Page 22Linked to original sources
PubMed1987

Differential ability of tumor-unique and cross-reactive antigen(s) on two murine hepatoma cell lines to induce Lyt-1+2- T cells responsible for in vivo protective immunity.

The role of the tumor-unique determinant(s) on two syngeneic murine hepatoma cells in inducing in vivo protective immunity was investigated in comparison with that of the tumor-cross-reactive determinant(s). Induction of vaccinia-reactive helper T cells in C3H/He mice by intraperitoneal (i.p.) inoculation of viable vaccinia virus and then immunization with vaccinia-infected syngeneic MH134 or MH129 tumor cells resulted in the production of potent anti-MH134 or -MH129 antibody as well as the generation of in vivo protective immunity. Neither antibody reacted with other syngeneic plasmacytoma or fibrosarcoma cells, but both cross-reacted appreciably with the other hepatoma cells as well reacted strongly as with the tumor cells used for immunization. The absorptions of anti-MH134 and -MH129 antisera with the respective hepatoma cells abolished their reactivities with both the corresponding hepatoma cells and the other hepatoma cells. In contrast, the absorption of these antisera with the other tumor cells resulted in loss of their cross-reactivities with the other hepatoma cells, but not loss of their specific reactivity to the respective hepatoma cells. Although in these hematoma systems, the above-mentioned immunization protocol resulted in in vivo induction of protective immunity and generation of antibodies, in vivo immunity as observed by Winn assays was mediated by Lyt-1+2- T cells and was specific for each type of hepatoma cells. These results indicate that these two types of hepatoma cells bear two kinds of antigenic determinants, one kind unique to each hepatoma and the other kind cross-reactive with the other hepatoma cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from urinary tract infections (1985). II. Background of patients].

We have investigated relationships between patients' backgrounds and isolates from urinary tract infections in reference to various conditions, such as sexes, age distribution by sex, species of causative organisms by sex, age distribution according to species and types of infections, species and infections before and after treatment with antibacterial agents, and species and detected places. As for the relationship between sexes and types of infections, although simple urinary tract infections were consistently found at about 20% in men and at about 80% in women between 1981 and 1983, these infections were seen at 24.4% in men and at 75.6% in women in 1984, and at 26.6% and at 73.4% in 1985, indicating slight decreases in the ratio of women. By contrast, complex urinary tract infections were found in men at about 60-70% from 1981 up to 1985, regardless of the presence or absence of indwelling catheter. There were no noticeable changes according to age during this 5-year period in incidences of infections including simple urinary tract infection and complex urinary tract infection with or without indwelling catheter. Thus, backgrounds of patients with urinary tract infections, including sex, age and simple or complex infections, were fairly consistent throughout this period, while there were relatively large changes in species of isolates. Enterococcus faecalis was isolated at about 8% of both men and women in 1982 and 1983, but its isolation rates were increased to 22.5% of men and 17.9% of women in 1984. In 1985 this species was isolated in 14.9% of men and 7.6% of women, and in 11.2% of all patients. Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus spp. and Enterococcus spp. were detected at rates of 3.2%, 8.1%, 0.7% and 1.0%, respectively, and 24.2% of isolated strains were Gram-positive organisms. When species of isolates before treatment with antibacterial agents and their isolation rates were analyzed, it was found that the isolation rate of E. faecalis increased dramatically in 1983, and that this tendency was still seen in 1984. The isolation rate of Gram-positive organisms was 25% in 1984 and 24.3% in 1985. Escherichia coli was consistently isolated at about 40%, but, as far as simple urinary tract infections are concerned, its isolation rate decreased by about 10% in 1985, compared to 1982 and 1983. These results suggested that causative organisms for simple urinary tract infections became similar to those for complex urinary tract infections. In other words, isolates obtained from complex urinary tract infections before treatment were similar to those of simple infections.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗
PubMed1987

Detection of Lea substance in saliva stains by enzyme-linked immunosorbent assay (ELISA) using anti-gum arabic serum.

It is known that rabbit anti-gum arabic (GA) serum has cross-reactivity with Lea antigen, and that, by using this cross-reactive anti-Lea antibody, the presence of Lea antigen in red blood cells and saliva can be demonstrated with accuracy. We have devised a rapid and highly sensitive method for detecting Lea substance in human saliva by the enzyme-linked immunosorbent assay (ELISA) method using an anti-Lea antibody isolated from anti-GA serum by affinity chromatography on Synsorb Lea. The ELISA plate, coated with the specific anti-Lea antibody, adsorbed the Lea substance in saliva which was subsequently identified by adding enzyme labeled anti-Lea IgG in that order. The method could detect the Lea substance in Le(a+) saliva stains as small as 0.1 by 0.1 cm in size that had been stored at room temperature for three weeks and in Le(a+) saliva stains 0.7 by 0.7 cm in size that had been stored for ten years. This method seems to be useful for quantitative analyses of the Lea substance in various body fluids.

Alkaline Phosphatase↗
PubMed1987

Metallic mercury in the arterial blood of normal and acatalasemic mice exposed to metallic mercury vapor.

Concentration of metallic mercury in the arterial blood was higher in acatalasemic mice after exposure to 3.45 mg/m3 for 10 minutes in comparison with normal mice, whereas concentration of mercuric ion was lower in acatalasemic mice than in normal mice. Thus, the ratio of metallic mercury to total mercury in the arterial blood of acatalasemic mice was 5.86 +/- 3.61%, which was statistically significantly higher than the value (1.36 +/- 0.65%) of corresponding normal mice. The mercury concentration and distribution in the brain and liver of acatalasemic mice were higher than those in normal mice. Data indicate that the concentration of metallic mercury in the arterial blood of acatalasemic mice was higher than that of normal mice and that metallic mercury soluble in lipids is likely transferred to the brain and liver from the blood. Conclusively, metallic mercury in the arterial blood is the biologically active form for transferring mercury from blood to organs.

Acatalasia↗
PubMed1987

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from urinary tract infections (1985). I. Susceptibility distribution].

The results of determinations of sensitivities of bacterial strains to various antibiotics are summarized as follows: 1. Against Escherichia coli, ofloxacin (OFLX) showed the strongest activity among oral antibacterial and antibiotic agents. Its MIC90 was below 0.10 micrograms/ml. The next strongest activity was found in mecillinam (MPC), cefaclor (CCL) and pipemidic acid (PPA); MIC90's of these agents 3.13 micrograms/ml. Cefotiam (CTM), cefotaxime (CTX), ceftizoxime (CZX), cefmenoxime (CMX) and latamoxef (LMOX) had MIC90 below 0.39 micrograms/ml. MIC90's of cefmetazole (CMZ) and cefoperazone (CPZ) were 1.56 micrograms/ml. Aztreonam (AZT) and carumonam (CRMN) in the monobactam group showed strong activities with MIC90's at 0.20 micrograms/ml. 2. Although Klebsiella pneumoniae had a strong resistance to ampicillin (ABPC) and showed relatively low sensitivities to other oral antibacterial and antibiotic agents, OFLX maintained high activity against this species and showed MIC90 of 0.39 micrograms/ml. Among injectable antibiotics, third generation cephems showed the strongest activity to this species with MIC90 of CZX below 0.10 micrograms/ml, of CTX and CMX 0.20 micrograms/ml, and of LMOX 0.78 micrograms/ml. MIC90 of CPZ was 6.25 micrograms/ml, which was the same as those of cefazolin (CEZ) and cefoxitin (CFX). CTM had similar MIC90 to LMOX, namely, 1.56 micrograms/ml. MIC90 of CMZ was 3.13 micrograms/ml. Monobactams AZT and CRMN showed strong activities to this species; their MIC90's were below 0.10 micrograms/ml and 0.20 micrograms/ml. 3. Although Citrobacter freundii generally exhibited low sensitivities to antibacterial and antibiotic agents examined, it showed high sensitivity to OFLX, at MIC80 of 0.78 micrograms/ml. This species showed low sensitivities to MPC, nalidixic acid (NA), PPA, and sulfamethoxazole-trimethoprim (ST). Among injectable antibiotics, LMOX and CMX had activities against this species; namely, MIC80's were 6.25 and 3.13 micrograms/ml, respectively. Among monobactams, AZT showed MIC80 of 12.5 micrograms/ml, and CRMN had that of 6.25 micrograms/ml. 4. Against Enterobacter cloacae, the strongest antibacterial activity was found with OFLX which had MIC90 of 0.39 micrograms/ml. A relatively strong activity was seen with MPC. MIC80 of MPC was 1.56 micrograms/ml. Except to CTM, this species had poor sensitivities to injectable first and second generation cephems, and their MIC80's were over 200 micrograms/ml. MIC80 of CTM was 25 micrograms/ml.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗
PubMed1987

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from urinary tract infections (1985). III. Secular changes in susceptibility].

Sensitivities to antimicrobial agents of Escherichia coli, Klebsiella spp., Citrobacter spp., Enterobacter spp., Proteus spp., Pseudomonas aeruginosa and Serratia marcescens isolated from infected patients were evaluated and compared according to the types of their infections, i.e., simple and complicated urinary tract infections with or without indwelling catheter. There were no apparent decreases in the sensitivity of E. coli isolated from patients with simple urinary tract infections. When data obtained in 1982-1985 were summarized, it was found that a new quinoline derivative, ofloxacin (OFLX), showed the strongest activity among oral antimicrobial and antibiotic agents. This agent inhibited 100% of bacterial growth at MIC of 1.56 micrograms/ml. The next strongest activity was found with mecillinam (MPC) which showed 89.3% growth inhibition at the same concentration. Cefaclor (CCL) also showed 84.9% growth inhibition at the same concentration. When sensitivities of E. coli isolated from patients with complicated urinary tract infections with or without indwelling catheter to first and second generation cephems were determined, cefotiam (CTM), which inhibited 88.9%: 91.4% bacterial growth at MIC of 0.39 micrograms/ml, had the strongest activity among CTM, cefazolin (CEZ), cefoxitin (CFX) and cefmetazole (CMZ). Among third generation cephems, including cefmenoxime (CMX), latamoxef (LMOX), ceftizoxime (CZX), cefotaxime (CTX) and cefoperazone (CPZ), the strongest activity was observed with CZX, and the agent having the next strongest activity was CMX. LMOX and CPZ showed relatively low activities. Carumonam (CRMN) and aztreonam (AZT), monobactams, showed strong activities against E. coli. As for Klebsiella spp., activities of pencillins against these strains were low. When activities of oral cephems (cephalexin (CEX) and CCL) and of a quinoline derivative OFLX against these strains were determined, OFLX showed strong activity; i.e., the growth of Klebsiella spp. isolated from complicated urinary tract infections was inhibited at 87.2%: 82.1% at MIC of 0.20 micrograms/ml.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Bacterial Agents↗
PubMed1986

Non-H-2-linked genetic regulation of cytotoxic responses to hapten-modified syngeneic cells. I. Non-H-2-linked Ir gene defect expressed on T cells is not predetermined at the stage of bone marrow cells.

Spleen cells from C3H/He or BALB.K mice immunized to the newly synthesized amino-reactive hapten 5-sulfo-1-naphthoxy acetic acid N-hydroxysuccinimide ester (AED-NH2) were stimulated in vitro with AED-NH2-modified syngeneic cells. After 5 days of culture, effector cells were assayed for their cytotoxic activity against AED-NH2-modified target blast cells. C3H/He and BALB.K mice exhibited the respective high and low anti-AED-NH2 cytotoxic T lymphocyte (CTL) responses. This contrasted with the observation that both of these H-2k strains generated potent CTL responses against aminoreactive haptens, e.g., trinitrophenyl (TNP). Because C3H.SW and BALB.B strains, which are the H-2b counterpart of the above two strains, also represented the respective high and low responders to AED-NH2 hapten, this hapten model enabled us to investigate cellular mechanisms underlying the above non-H-2-associated genetic regulation of CTL responses (C3H vs BALB non-H-2 backgrounds). The results demonstrated that there was no detectable difference between C3H/He and BALB.K strains in the lysability of target cells and the ability of stimulating cells to activate primed spleen cells. Anti-AED-NH2 CTL responses were only marginal when antigen-presenting cells (APC) were eliminated from the primed spleen cells of high responder C3H/He or (C3H/He X BALB.K)F1 mice. The addition of APC to cultures free of APC regained an appreciable CTL response in C3H/He or (C3H/He X BALB.K)F1 mice, irrespective of whether APC were derived from high (C3H/He) or low (BALB.K) responders. We have also demonstrated that allogeneic radiation bone marrow chimera (BALB.K----C3H/He) exhibited a CTL response comparable to that induced by C3H/He mice, whereas the reverse direction of allogeneic chimera (C3H/He----BALB.K) induced a marginal CTL response. These results indicate that this non-H-2-associated Ir gene defect is expressed on T cells (CTL precursors and/or helper T cells) rather than APC, and that this T cell defect is not predetermined at the level of bone marrow cells. The results are discussed in the light of the genetic and cellular mechanisms underlying non-H-2-linked Ir gene control.

Animals↗
PubMed1986

Quantitative analysis of urinary glycine conjugates by high performance liquid chromatography: excretion of hippuric acid and methylhippuric acids in the urine of subjects exposed to vapours of toluene and xylenes.

A new method for the direct determination of hippuric acid (HA) and o-, m- and p-methylhippuric acids (MHAs) in the urine, metabolites of toluene and o-, m- and p-xylenes by high performance liquid chromatography (HPLC) is described. A stainless-steel column packed with silica gel having dinitrophenyl residue and a mixed solution of methanol/water/acetic acid (80/20/0.2) containing tetra-n-butylammonium bromide (0.2% w/v) as mobile phase was used. Concentrations of HA and MHAs were estimated from their peak height at a wave length of 225 nm. Urine can be analyzed directly without solvent extraction or pretreatment to obtain complete separation of HA and o-, m- and p-MHAs. Urine samples from male workers exposed to toluene or xylenes were analyzed for HA or MHAs. The urinary levels of HA and MHAs increased by exposure to toluene and xylenes in proportion to the environmental concentrations of the solvents, although there is a considerable variation in metabolite concentrations. The slope of regression line between toluene and HA and that between m-xylene and m-MHA were similar. The urinary concentrations of HA and MHAs corresponding to 100 ppm (TLV) of toluene was 2.35 g/g creatinine and that of m-MHA corresponding to 100 ppm (TLV) of m-xylene was 2.05 g/g creatinine. The warning levels of the urinary metabolite concentrations of a group of workers and that of an individual worker corresponding to TLV of organic solvent concentration is discussed.

Adult↗
PubMed1986

Significance of urinary phenyl sulfate and phenyl glucuronide as indices of exposure to phenol.

Urine samples from subjects, who had been using phenol for treatment of chemical fiber in factories, were analysed for urinary phenyl sulfate (PhS) and phenyl glucuronide (PhG) by high-performance liquid chromatography (HPLC). The urinary levels of phenol metabolites (PhG and PhS) had a significant correlation with the environmental concentration of phenol. The urinary concentration of phenol metabolites, as a total of PhS and PhG, corresponding to 5 ppm of environmental phenol was 251 mg phenol/g creatinine.

Chromatography, High Pressure Liquid↗
PubMed1986

Synthesis and antiviral activity of sulfonamidobenzophenone oximes and sulfonamidobenzamides.

To find antiviral agents, various sulfonamidobenzophenone oximes (II) were synthesized from the appropriate m-sulfonamidobenzophenones by hydroxylamine reaction. The reaction products were generally obtained as syn/anti mixtures which were separable by fractional crystallization. The anti isomer had more potent antipoliovirus activity than the syn isomer. Various sulfonamidobenzamides (III) which were structurally related to II were synthesized by the reactions of amino-substituted benzamides with sulfuryl chloride or amines with (aminosulfonyl)benzoyl chloride. Antiviral activity was examined by the plaque-inhibition test. Compounds 5, 36, and 69 exhibited strong antipicornavirus activity. The structure-activity relationships are discussed.

Animals↗
PubMed1986

Pyruvate dehydrogenase and the path of lactate degradation in Desulfovibrio vulgaris Miyazaki F.

Pyruvate dehydrogenase from Desulfovibrio vulgaris Miyazaki F was partially purified from the soluble fraction of the bacterial sonicate, and characterized. The enzyme catalyzes oxidative decarboxylation of pyruvate to produce acetyl-CoA, in contrast to statements in current review articles in which acetyl phosphate is indicated to be a direct decomposition product of pyruvate in sulfate-reducing bacteria. The established reaction stoichiometry is: pyruvate + CoA + FMN----acetyl-CoA + CO2 + FMNH2. The Km values are 2.9 mM for pyruvate, 32 microM for CoA and 6.7 mumol for FMN. Participation of thiamine diphosphate in the enzymic process was not proven. 2-Oxobutyrate, but not 2-oxoglutarate, can substitute for pyruvate. The three flavin compounds, FMN, FAD, and flavodoxin, as well as clostridial ferredoxin, serve as electron carriers for the enzyme. Thus the enzyme is a kind of pyruvate synthase [EC 1.2.7.1], but acts in the direction of pyruvate degradation in the growing cells. The rate of cytochrome C3 reduction is extremely low, but in the presence of flavodoxin as an electron mediator, the reduction rate of cytochrome C3 becomes faster than the reduction rate of flavodoxin alone. It seems that the physiological electron acceptor for this enzyme is flavodoxin, which might be complexed with cytochrome C3 to produce a very efficient electron transfer system in the cell. The soluble fraction of D. vulgaris cells has been proved to contain, in addition to the pyruvate dehydrogenase, lactate dehydrogenase (Ogata, M., Arihara, K., & Yagi, T. (1981) J. Biochem. 89, 1423-1431), phosphate acetyltransferase and acetate kinase, i.e., all the enzymes necessary to convert lactate to acetate, producing ATP by substrate level phosphorylation.

Acetyl Coenzyme A↗
PubMed1986

Role of L3T4 antigen in the activation of various functions of Lyt-1+2- T cells against vaccinia virus.

The present study defines assay systems for vaccinia virus-reactive Lyt-1+2- T cells mediating various functions and investigates the positivity of L3T4 antigen on these Lyt-1+2- T cells as well as the role of L3T4 antigen in the activation of these T cells with respect to their functions. C3H/He mice were immunized against vaccinia virus by inoculating viable virus intraperitoneally (i.p.). Anti-vaccinia virus reactivity in lymphoid cells from these immunized mice was assessed by proliferative response, helper T cell activities involved in cytotoxic T lymphocyte (CTL) and B cell (antibody) responses, delayed type-hypersensitivity (DTH) response, and production of lymphokines such as interleukin 2 (IL2) and macrophage-activating factor (MAF). The results demonstrate that all of the above anti-vaccinia virus responses were mediated by Lyt-1+2- T cells and that these Lyt-1+2- T cells expressed L3T4 antigens on their cell surfaces. Moreover, such anti-vaccinia Lyt-1+2- T cell responses were inhibited in the presence of anti-L3T4 antigen antibody. These results indicate that there is a reciprocal relationship between Lyt-2 and L3T4 markers, and that L3T4 antigen is closely related to the activation of various functions of anti-vaccinia virus Lyt-1+2- T cells.

Animals↗