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Y Takeda

Publications and source records attributed to Y Takeda.

At least 739 records · Page 41Linked to original sources
PubMed1992

[Enteroadherent Escherichia coli exhibiting localized pattern of adherence among infants with diarrhoea in Brazil--incidence and prevalence of serotypes].

The incidence of enteroadherent Escheridhia coli exhibiting localized adherence to HeLa cells was investigated using the EAF probe (Nataro et al., J. Infect. Dis., 152:560-563, 1985) among 126 infants below 3 years of age along with 126 age-matched healthy controls in Brazil. The EAF probe proved to be sensitive and specific in detection of enteroadherent E. coli. EAF-probe positive E. coli was isolated from 23.0% of the infants with acute diarrhoea while the corresponding rate of isolation from healthy controls was 11.9%. EAF-probe positive E. coli strains belonging to the classical enteropathogenic E. coli (EPEC) serogroups were more often associated with diarrheal cases (18.3%) than with strains isolated from control healthy infants (5.6%). The predominant EAF-probe positive E. coli serotypes were O55:H-, O111:H2 and O119:H6. These serotypes, especially O111:H2, were mainly isolated from cases with diarrhoea suggesting a strong causal association. Among the EAF positive non-EPEC serotypes, the most prevalent serotype was O88:H25 and this represents a, hitherto, unrecognized diarrheagenic E. coli serotype.

Bacterial Adhesion↗
PubMed1992

[Isolation of vero-cytotoxin-producing Escherichia coli from cattle and serotyping and toxin-typing of the isolated strains].

Two hundred and sixty-six piglets with diarrhea (from 4 farms), 73 healthy pregnant pig (from 2 farms), 27 calves with diarrhea (from 9 farms) and 47 healthy milk cows (from 1 farm) were examined for Vero-cytotoxin-producing Escherichia coli (VTEC), and 52, 11, 15 and 67 strains of VTEC were isolated from 17 piglets, 11 pregnant pigs, 6 calves and 23 milk cows, respectively. All VTEC strains from the piglets produced only VT2vp, while the strains from the healthy pigs did not produce VT2vp, but did VT1 and/or VT2. Most VTEC strains from calves and cows produced VT2vhb and some produced VT2 and VT1. Serotyping of the isolated strains showed that many strains from the piglets belonged either O139:H1, O141:H4 or O141:HUT, but the strains from the pigs were either R-form or O-untypable. Many strains from the calves and cows were serotyped into O116 or O113, but there were several R-form and O-untypable. From these results, it is suggested that VTEC strains, especially from the pregnant pigs, calves with diarrhea and healthy milk cows, which produced the same type of Verotoxins to that produced by human isolates, may become sources of human infections.

Animals↗
PubMed1992

Sequence variation in the thermostable direct hemolysin-related hemolysin (trh) gene of Vibrio parahaemolyticus.

Our previous molecular epidemiologic study with gene probes (H. Shirai, H. Ito, T. Hirayama, Y. Nakamoto, N. Nakabayashi, K. Kumagai, Y. Takeda, and M. Nishibuchi, Infect. Immun. 58:3568-3573, 1990) demonstrated that the gene (trh) encoding a thermostable direct hemolysin-related hemolysin was strongly associated with clinical strains of Vibrio parahaemolyticus. Strain-to-strain variation in the intensities of the hybridization signals observed in the above study also suggested that the trh genes in different strains may have significantly divergent nucleotide sequences. To assess the public health significance of the rare environmental strains which exhibited very weak hybridization signals with the trh gene-specific DNA probe, the trh-like sequence was cloned from one of the environmental strains and the nucleotide sequence was determined in this study. A hemolysin gene (trh2) which was 84% homologous to the trh gene (newly named trh1) and 54.8 to 68.8% homologous to the genes (tdh) encoding thermostable direct hemolysins was detected in the cloned sequence. The trh2 gene product showed a profile of hemolytic activities against various animal erythrocytes different from that of the trh1 gene product. The trh2 gene product was antigenically related (partially identical) to the trh1 and tdh gene products. DNA colony blot and Southern blot hybridization analyses with trh1- and trh2-specific DNA probes showed that the trh1 probe-positive strains exhibiting hybridization signals with varying intensities could be clustered into trh1 and trh2 subgroups. In addition, hybridization analysis with oligonucleotide probes demonstrated significant strain-to-strain variation in the trh1 and trh2 gene sequences.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1992

Reassessment of the prevalence of heat-stable enterotoxin (NAG-ST) among environmental Vibrio cholerae non-O1 strains isolated from Calcutta, India, by using a NAG-ST DNA probe.

A collection of 521 environmental isolates of Vibrio cholerae which were previously examined by the suckling mouse assay and found to be negative for the heat-stable enterotoxin NAG-ST were reassessed by a recently developed DNA probe for NAG-ST. A total of 12 (2.3%) of the isolates hybridized with the NAG-ST probe. By using a cholera toxin (CT) DNA probe, the CT gene was detected in six of the strains in the collection, although none of the isolates of V. cholerae non-O1 hybridized with both of the toxin probes. All of the NAG-ST and CT probe-positive strains were hemolysin positive. Thirty-fold-concentrated supernatants of the three representative NAG-ST DNA probe-positive V. cholerae non-O1 strains gave positive fluid accumulation ratios in the suckling mouse assay even after heating (100 degrees C for 5 min) and also inhibited the binding of a NAG-ST monoclonal antibody to the bound NAG-ST in a competitive enzyme-linked immunosorbent assay (ELISA). Likewise, all six CT probe-positive V. cholerae non-O1 strains produced in vitro CT when examined by the CT bead ELISA. HindIII digest patterns of chromosomal DNA from the representative NAG-ST gene-positive strains were visually indistinguishable. Between the groups of NAG-ST probe-positive strains examined, there was a variation in the hybridizable fragments, with one group of strains exhibiting a hybridizable fragment similar to that of the NRT 36 reference strain; a smaller HindIII fragment hybridized with the NAG-ST probe in the other group of strains.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Glycoprotein receptors for a heat-stable enterotoxin (STh) produced by enterotoxigenic Escherichia coli.

Glycoprotein receptors for heat-stable enterotoxin STh of enterotoxigenic Escherichia coli in the rat intestinal cell membrane were identified and characterized. Incubation of rat intestinal cell membranes with radioiodinated N-5-azidonitrobenzoyl-STh[5-19] (125I-ANB-STh[5-19]) followed by photolysis resulted in specific radiolabeling of two distinct proteins with M(r)s of 200,000 (designated STR-200A and STR-200B). STR-200A was found to be composed of two molecules of a protein with an M(r) of 70,000 (70-kDa protein), whereas STR-200B was composed of two different protein molecules with M(r)s of 53,000 (53-kDa protein) and 77,000 (77-kDa protein). These proteins showed no guanylate cyclase activity. The 70-kDa protein was labeled most with 125I-ANB-STh[5-19], suggesting that STR-200A is the main receptor protein in the rat intestinal cell membrane. The carbohydrate moieties of STR-200A and STR-200B were examined by enzymatic deglycosylation. The 70-kDa protein of STR-200A was found to contain N-linked high-mannose-type and/or hybrid-type oligosaccharides, and results suggested that it possesses at least three N glycosylation sites. The 53-kDa protein of STR-200B was found to have an N-linked complex-type oligosaccharide side chain. The deglycosylated 70-kDa protein retained activity for binding to STh, suggesting that the carbohydrate moieties of these receptor proteins are not important for binding with STh.

Animals↗
PubMed1992

Evaluation of the bead enzyme-linked immunosorbent assay for detection of cholera toxin directly from stool specimens.

A highly sensitive bead enzyme-linked immunosorbent assay (bead ELISA) for detection of cholera toxin (CT) was evaluated for direct detection of CT from stool specimens of patients with acute secretory diarrhea. Of the 75 stool samples examined, 59 yielded biochemically, and serologically confirmed strains of Vibrio cholerae O1. The bead ELISA was positive for CT in stool supernatants in 50 (84.7%) of the 59 samples from which V. cholerae O1 was isolated. In addition, the bead ELISA was positive for three stool specimens which were negative by culture. The free CT present in 48 of the 50 stool samples positive by culture for V. cholerae O1 and for CT by bead ELISA was completely absorbed by anti-CT immunoglobulin G. All of the 59 strains of V. cholerae O1 biotype eltor isolated in this study produced in vitro CT. The concentration of CT present in the bead ELISA-positive stool samples ranged between 26 pg/ml and greater than 100 ng/ml. This evaluation study demonstrates that the bead ELISA is a sensitive and simple method for direct detection of CT in nonsterile stool samples, and we recommend routine use of this assay for detection of CT in stool samples and culture supernatants in clinical and reference laboratories.

Cholera Toxin↗
PubMed1992

Argyrophilic proteins of the nucleolar organizer region in acute leukemias and its relation to the S-phase fraction of leukemic cells.

Nucleolar organizer regions (NORs) are loops of DNA which transcribes to ribosomal RNA. The NOR-related protein becomes visible in nucleus by a silver-staining technique under a light microscope, and it has been named argyrophilic protein of NOR (Ag-NOR). In various malignancies, the correlation between the proliferation potential of tumor cells or histological grade and the number of Ag-NORs has been reported. In this study, we investigated the Ag-NOR of acute leukemic cells and its relation to the in vivo proportion of bone marrow leukemic cells in DNA synthetic phase. The number of Ag-NORs in bone marrow leukemic cells was more than that in peripheral blood (means values 2.78 and 2.48, respectively, p less than 0.01). This result shows that the number of Ag-NORs reflects the vigorous proliferative potential of bone marrow leukemic cells. However, no significant correlation was obtained between the number of Ag-NORs and the bromodeoxyuridine-labeling indices (r = 0.2064). These results suggest that Ag-NOR might be one of the markers for cellular proliferation in leukemia, while DNA synthesis of leukemic cells do not seem to be directly related to Ag-NOR. In order to clarify the role of Ag-NOR in leukemia, further studies are needed.

Adolescent↗
PubMed1992

Phospholipase C-mediated hydrolysis of phosphatidylcholine is activated by cis-diamminedichloroplatinum(II).

We have investigated the effect of cis-diamminedichloroplatinum(II) (CDDP) on signal transduction pathways. CDDP treatment did not cause any change in the binding of [3H]-phorbol dibutyrate to PC-9 (human lung adenocarcinoma cell line) cells, a measure of protein kinase C activation. However, 2-h CDDP treatment (20 micrograms/ml) caused approximately 200% increase in 1,2-sn-diacylglycerol (DAG) production and approximately 50% decrease in inositol 1,4,5-triphosphate production. To explore the different source of DAG, we analyzed phospholipids labeled with [14C]choline by TLC and revealed that [14C]choline-labeled phosphatidylcholine (PC) was decreased to 50% by CDDP treatment. This suggested that PC turnover was increased by CDDP-treatment. PC-specific phospholipase C (PC-PLC) activity was increased to 2.5-fold (2.58 +/- 0.28 nmol/mg protein per min) by 2 h CDDP (20 micrograms/ml) treatment compared with control (1.05 +/- 0.24 nmol/mg protein per min). Treatment of CDDP also stimulated PC-PLC in the crude membrane extract from PC-9 cells. CDDP had no effect on the activities of phospholipase A2 and D. Trans-DDP, which has far less cytotoxicity than its stereoisomer, CDDP, did not cause any change in PC-PLC activity. A significant inhibition of DNA synthesis (less than 80%) occurred 4 h after 2 h CDDP (20 micrograms/ml) treatment. These results demonstrated that CDDP-induced PC-PLC activation was an early event in CDDP-induced cytotoxicity and suggested that the effects of CDDP on signal transduction pathways had an important role in CDDP-induced cytotoxicity.

Cisplatin↗
PubMed1992

Effect of sodium restriction on urinary excretion of 19-noraldosterone and 18,19-dihydroxycorticosterone, newly identified mineralocorticoids in man.

19-Noraldosterone, which was recently shown to be synthesized and produced in the human adrenal gland, possesses potent mineralocorticoid activity. 18,19-Dihydroxycorticosterone [18,19-(OH)2B], a possible precursor of 19-noraldosterone, has also been identified in human urine. To elucidate the regulatory mechanism for these newly described steroids, we studied the effect of sodium restriction on the urinary excretion of 19-noraldosterone and 18,19-(OH)2B in six normal subjects. 18,19-(OH)2B and 19-noraldosterone were measured by specific RIAs after purification of the urine extract by high performance liquid chromatography. The 24-h urinary excretion of 19-noraldosterone and 18,19-(OH)2B during the control period were 107 +/- 40 (+/- SE) pmol/day and 5.6 +/- 0.8 nmol/day, respectively. After sodium restriction, the values increased approximately 2-fold (P less than 0.05), to 259 +/- 76 pmol/day and 15.6 +/- 4.5 nmol/day, respectively. Virtually identical responses were seen for aldosterone (from 21 +/- 6.0 to 38 +/- 10 nmol/day), 18-hydroxycorticosterone (from 9.9 +/- 1.1 to 21 +/- 2.8 nmol/day), and 18-hydroxycortisol (from 377 +/- 93 to 554 +/- 129 nmol/day). These observations suggest that 19-noraldosterone and 18,19-(OH)2B are partly under the control of the renin-angiotensin system in normal subjects.

18-Hydroxycorticosterone↗
PubMed1992

The enantioselective metabolism of p-cymene in rabbits.

p-Cymene (1) was metabolized in rabbits and the following four optically active metabolites, 2-(p-tolyl)-1-propanol (3': R/S = 65:35), 2-(p-tolyl)propanoic acid (5': R/S = 0:100), p-(2-hydroxy-1-methylethyl)benzoic acid (6': R/S = 91:9) and p-(1-carboxyethyl)benzoic acid (8': R/S = 30:70), were isolated in addition to three optically inactive metabolites, 2-(p-tolyl)-2-propanol (2), p-isopropylbenzoic acid (4'), and p-(1-hydroxy-1-methylethyl)benzoic acid (7'). The presumed metabolic pathways of p-cymene in rabbits were confirmed by the administration of the intermediate metabolites (2, 3', 4', and 5'). The enantiomeric ratios of the metabolites, 3' and 6', suggested that omega-hydroxylations of the isopropyl group in 1 and 4' occurred preferentially at the pro-S methyl group. In the metabolism of 1, the S-isomers are predominant in the propanoic acid derivatives, but the R-isomers are rich in the propanol derivatives. It is of interest that the metabolism of 4', however, produced predominantly the corresponding propanol derivative (6'; R/S = 91:9) and propanoic acid derivative (8'; R/S = 80:20) possessing the same R-configuration. Some optically active p-cymene derivatives were also synthesized as standard compounds.

Animals↗
PubMed1992

Lobenzarit disodium (CCA) inhibits in vitro immunoglobulin production via direct interaction with B lymphocytes.

The regulatory effects of lobenzarit disodium (CCA), a therapeutic agent for treating rheumatoid arthritis (RA), on polyclonal immunoglobulin production by human lymphocytes were investigated in vitro. CCA inhibited the production of immunoglobulin in all the classes examined at a clinically relevant concentration. Moreover, it inhibited the immunoglobulin production as well as lymphocyte proliferation even when purified B lymphocytes preactivated by Staphylococcus aureus COWAN I were cultured with recombinant lymphokines such as IL2 and IL6. These results suggest that CCA acts directly on B lymphocytes. The analysis at each of two different stages of B lymphocyte activation lineage, i.e., the primary activation stage and a stage of proliferation and differentiation to antibody secreting cells, has indicated that CCA inhibits the proliferation-differentiation stage of B lymphocytes. CCA does not inhibit B lymphocytes at the primary activation stage; actually, it augments them, resulting in the subsequent enhancement of immunoglobulin production.

Adult↗
PubMed1992

Indonesian medicinal plants. I. Chemical structures of calotroposides A and B, two new oxypregnane-oligoglycosides from the root of Calotropis gigantea (Asclepiadaceae).

Two new oxypregnane-oligoglycosides named calotroposides A (1) and B (2) have been isolated from the root of Calotropis gigantea (Asclepiadaceae), an Indonesian medicinal plant, and their chemical structures have been elucidated by chemical and spectroscopic methods as 12-O-benzoyllineolon 3-O-beta-D-cymaropyranosyl(1----4)-beta-D-oleandropyranosyl( 1----4)- beta-D-oleandropyranosyl(1----4)-beta-D-cymaropyranosyl(1--- -4)-beta-D- cymaropyranoside and 12-O-benzoyldeacetylmetaplexigenin 3-O-beta-D-cymaropyranosyl(1---4)-beta-D-oleandropyranosyl(- ---4)- beta-D-oleandropyranosyl(1----4)-beta-D-cymaropyranosyl(1--- -4)- beta-D-cymaropyranoside, respectively.

Parasympathomimetics↗
PubMed1992

Effect of methotrexate treatment on the onset of autoimmune kidney disease in lupus mice.

In the present study, we examined the effects of methotrexate (MTX) on the development of autoimmune kidney disease in three kinds of autoimmune prone mice, NZB/NZW F1 (BWF1) mice, MRL/Mp-lpr/lpr (MRL/lpr) mice and NZW/BXSB F1 (WBF1) mice. The results showed that MTX delayed the appearance of proteinuria and prolonged survival of both BWF1 and MRL/lpr mice and inhibited the elevation of blood urea nitrogen (BUN) levels which accompanies the development of lupus nephritis. However, MTX treatment did not affect these in WBF1 mice. Furthermore, MTX could not suppress immunoglobulin G (IgG) class anti-deoxyribonucleic acid (DNA) and anti-trinitrophenol (TNP) antibody production in any variety of mice. These suggest that the therapeutic effect of MTX on BWF1 and MRL/lpr mice does not result in the suppression of IgG autoantibody production.

Animals↗
PubMed1992

Indonesia medicinal plants. III. On the constituents of the bark of Fagara rhetza (Rutaceae). (1): Alkaloids, phenylpropanoids, and acid amide.

Two new phenylpropanoids, named O-geranylsinapyl alcohol (1) and O-geranylconiferyl alcohol (2), and a new acid amide, named hazeleamide (3), were isolated from the bark of Fagara rhetza (Rutaceae), an Indonesian medicinal plant from Flores Island, Indonesia. The chemical structures of 1, 2, and 3 have been elucidated on the basis of their chemical and physicochemical properties. Among the three new compounds, hazeleamide (3) was found to show a pungent taste and to exert a moderate antimalarial activity in an in vitro test system.

Alkaloids↗
PubMed1992

Urinary excretion of 19-noraldosterone, 18, 19-dihydroxycorticosterone and 18-hydroxy-19-norcorticosterone in patients with aldosterone-producing adenoma or idiopathic hyperaldosteronism.

Urinary excretion of 19-noraldosterone, 18. 19-dihydroxycorticosterone (18, 19(OH)2-B), 18-hydroxy-19-norcorticosterone (18-OH-19-nor-B), 18-hydroxycorticosterone (18-OH-B), 18-hydroxycortisol (18-OH-F) and aldosterone were measured in 25 patients with primary aldosteronism, 16 with an aldosterone-producing adenoma and 9 with idiopathic hyperaldosteronism. In patients with idiopathic hyperaldosteronism, urinary 19-noraldosterone (207 +/- 51 pmol/day), 18, 19(OH)2-B (21 +/- 4.2 nmol/day) and 18-OH-19-nor-B (879 +/- 213 pmol/day) levels were lower but not significantly different from 19-noraldosterone (263 +/- 56 pmol/day), 18, 19(OH)2-B (40 +/- 8.7 nmol/day) and 18-OH-19-nor-B (1322 +/- 267 pmol/day) seen in patients with aldosterone-producing adenoma. Urinary aldosterone did not differ significantly between patients with idiopathic hyperaldosteronism and those with aldosterone-producing adenoma. Both urinary 18-OH-B and 18-OH-F excretion were significantly higher in aldosterone-producing adenoma (39 +/- 5.2 nmol/day, 1660 +/- 318 nmol/day, respectively) compared with patients with idiopathic hyperaldosteronism (19 +/- 3.3 nmol/day, 541 +/- 93 nmol/day, respectively) (p less than 0.05). Though urinary 18-OH-F and 18-OH-B concentrations were useful markers, the mineralocorticoid steroids which we can only now measure, 19-noraldosterone, 18, 19(OH)2-B and 18-OH-19-nor-B, could not be used to distinguish the two subsets of primary aldosteronism.

18-Hydroxycorticosterone↗
PubMed1992

Augmentation of mitogen-induced interleukin 2 production by oral administration of polysaccharide SPR-901.

The effects of oral administration of antitumor polysaccharide SPR-901 (RBS), an alpha-1,3 branched alpha-1,6 glucan, on concanavalin A (Con A)-induced interleukin 2 (IL-2) production of splenocytes were studied. The augmentation effect on Con A-induced IL-2 production was evident when more than 30 mg/kg of SPR-901 was administered orally to mice. On the other hand, oral administration of B512 dextran, an analogous alpha-1,6 glucan, did not show any augmentation effects on IL-2 production. The augmentation effect of SPR-901 on IL-2 production seemed to be mediated mainly by macrophages stimulated with SPR-901.

Adjuvants, Immunologic↗
PubMed1992

[Application of bromodeoxyuridine (BrdU) and anti-BrdU monoclonal antibody for the analysis of tumor cell kinetics by flow cytometry].

Bromodeoxyuridine (BrdU) is a thymidine analogue which is incorporated into the cells of DNA synthetic phase. BrdU-labeling index (BrdU-LI) of tumor cells can be estimated with an anti-BrdU antibody. Bivariate distributions of BrdU and DNA content are simultaneously obtained by flow cytometric two parameter analysis with a double staining method. The exact DNA synthetic cells are determined using this method by removal of the cells having S phase DNA content without DNA synthesis; quiescent (S0) cells. Once the BrdU-LIs are obtained, DNA synthesis time (Ts) and other time parameters of tumor cell kinetics can be calculated by mathematical methods. BrdU and anti-BrdU monoclonal antibody makes it possible to easily and rapidly recognize the tumor cell kinetics with high accuracy.

Antibodies, Monoclonal↗