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Biomedical subjects

T Baba

Publications and source records attributed to T Baba.

At least 487 records · Page 27Linked to original sources
PubMed1986

Determination of molecular species composition of C80 or longer-chain alpha-mycolic acids in Mycobacterium spp. by gas chromatography-mass spectrometry and mass chromatography.

The molecular species composition of alpha-mycolic acids ranging from C68 to C86 in 13 rapidly growing and 12 slowly growing mycobacterial species was determined by gas chromatography, gas chromatography-mass spectrometry, and mass chromatography. In gas chromatographic analysis, the molecular species of alpha-mycolic acids were well separated as trimethylsilyl ether derivatives of the methyl esters, according to their total carbon numbers. The total carbon and double-bond numbers of mycolic acids at each peak on gas chromatograms were determined from the [M]+, [M - 15]+, and [M - 90]+ ions on the mass spectrum, and straight and branched chain structures were identified by the mass fragment ions [A]+, due to C2--C3 cleavage [R-CH-O-Si(CH3)3]+, and [B]+, due to C3--C4 cleavage [(CH3)3-Si-O-CH-CH(R')-COOCH3]+. The concentration of odd- and even-carbon-numbered mycolic acids, which often overlap each other on gas chromatograms, and the composition of three homologous mycolic acids with different alpha units (C22:0, C24:0, and C26:0) were clearly determined by mass chromatography monitoring [M - 15]+ ions and [B - 29]+ ions, respectively. The molecular species composition of alpha-mycolic acids and their average carbon numbers (av. cn.) as a simple expression of the composition were calculated from the mass chromatograms. Each mycobacterial species examined was demonstrated to possess a characteristic profile of alpha-mycolic acid composition, and based on this the species were classified approximately into eight groups: C68 to C76 (av. cn. 72), dienoic, possessing a C20 alkyl branch at the 2 position (C22 alpha-unit) for Mycobacterium diernhoferi and Mycobacterium sp. strain 3707, a chromogenic rapid grower; C72 to C78 (av. cn. 75), dienoic with both C22 and C24 alpha units, containing a small or a large amount of odd-carbon-numbered molecules, for M. vaccae, M. rhodesiae, and M. phlei (chromogenic rapid growers); C72 to C80 (av. cn. 75 to 77), dienoic with C24 alpha-unit, containing a moderate or a large amount of odd-carbon-numbered molecules, for M. smegmatis, M. chitae, M. chelonae (M. chelonei), and M. fortuitum (nonchromogenic rapid growers); C78 to C82 (av. cn. 80), even-carbon-numbered dienoic with C24 alpha unit for M. agri and M. thermoresistible (rapid growers); C75 to C81 (av. cn. 77 to 79), odd-carbon-numbered dienoic with C24 alpha unit for M. nonchromogenicum complex (M. nonchromogenicum, M. terrae, and "M. novum") (slow growers); (vi) C76 to C84 (av. cn. 79 to 81), even-carbon-numbered dienoic with C24 alpha unit for MAIS complex including M. scrofulaceum, M. avium, and M. intracellulare (slow growers); (vii) C72 to C80 (av. cn. 77 to 79), even-carbon-numbered dienoic with C24 alpha unit for M. szulgai, M. gordonae, and M. kansasii (chromogenic slow growers); and (viii) C76 to C86 (av. cn. 79 to 81), even-carbon-numbered dienoic with C26 alpha unit M. bovis Ravenol and BCG and M. tuberculosis H37Rv. This study demonstrated that gas chromatography-mass spectrometric analysis of the molecular species composition of alpha-mycolic acid can give rapid, important, and very precise information for the identification of pathogenic and nonpathogenic mycobacterial species.

Chromatography, Gas↗
PubMed1986

Investigation of regional differences in water and electrolyte absorption across the human colon by in vivo perfusion method.

Colonic perfusion studies were performed to evaluate regional differences in water and electrolyte absorption across the human colon. In 19 healthy male volunteers, a 5-lumen tube with two balloons was inserted into the colon by the endoscopic retrograde bowel insertion (ERBI) method and a 25 cm segment of either the right or the left colon was perfused with an isotonic electrolyte solution simulating the fasting ileal content at a rate of 5 ml/min. Additionally into 5 subjects of the right colon and 5 subjects of the left colon, PSP solution was injected and mean transit time was calculated by the dilution method. Higher absorption rates of water, Na and Cl were observed in the right than in the left colon. Mean transit time was longer in the left than in the right colon. It was considered that the right colon had greater absorptive capacity than the left. The colonic perfusion study by the use of ERBI method made it possible to determine the absorption of water and electrolytes in the right and left colon directly in man, and would be useful to elucidate the pathophysiology of colonic diarrhea.

Adolescent↗
PubMed1986

Renal effects of nicardipine, a calcium entry blocker, in hypertensive type II diabetic patients with nephropathy.

We studied the renal effects of nicardipine, a calcium entry blocker, in eight patients with essential hypertension (group A, WHO I or II), six hypertensive type II diabetics with mild-to-moderate nephropathy (group B, urinary albumin 200-789 mg/day), and six hypertensive type II diabetics with severe or advanced nephropathy (group C, urinary albumin 1,596-4,300 mg/day). The patients received an intravenous dose of nicardipine hydrochloride (0.5 mg) or saline placebo in a random order. Glomerular filtration rate (GFR) and renal blood flow (RBF) were measured by means of thiosulfate sodium and p-aminohippurate, respectively, during the 30 min after the nicardipine or saline injection. Blood pressures were serially monitored during the study. Nicardipine reduced both systolic and diastolic blood pressures significantly (P less than .05 to .01) at all measurement periods in all study groups compared with the respective placebo. Nicardipine increased RBF (P less than .01), GFR (P less than .05), and urinary Na+ excretion (P less than .01) and decreased total renal vascular resistance (P less than .01) in groups A and B, but these parameters remain unchanged in group C. The filtration fraction remained unaltered in all groups. The results indicate that nicardipine has several favorable renal effects with a concomitant hypotensive action in hypertensive type II diabetics with mild-to-moderate nephropathy, as observed in patients with uncomplicated essential hypertension, and the renal pharmacological responsiveness appears to be related to the severity of nephropathy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Some cardiotonics enhance the effectiveness of angiotensin II-induced hypertension cancer chemotherapy in mice.

Angiotensin II-induced hypertension chemotherapy proved to be more effective than conventional chemotherapy using cis-diamminedichloroplatinum (II) (DDP), when applied to an established mouse mammary carcinoma. In an attempt to improve the effectiveness, a cardiotonic such as aminophylline or trans-pi-oxocamphor was added to a solution containing angiotensin II and DDP. A remarkable improvement in therapeutic efficacy was apparent as compared to angiotensin II hypertension chemotherapy. A possible synergism between angiotensin II and the cardiotonic may result in selective delivery of the antitumor drug to the tumor tissue.

Aminophylline↗
PubMed1986

fos oncogene transfer to a transformed rat fibroblast cell line enhances spontaneous lung metastasis in rat.

When investigating the relationship of different oncogenes to metastasis, we found that transfer of the v-fos oncogene into a transformed rat cell line augmented spontaneous lung metastasis. The metastatic potential of the cell lines examined depended on the manner of integration and the extent of transcription of the fos genes. Thus, the fos oncogene is probably involved in certain events related to acquisition of metastatic potential.

Animals↗
PubMed1985

Photoaffinity labeling of undecaprenyl pyrophosphate synthetase with a farnesyl pyrophosphate analogue.

The prenyl transferase undecaprenyl pyrophosphate synthetase was partially purified from the cytosolic fraction of Escherichia coli. Its enzymic products were characterized as a family of cis-polyprenyl phosphates, which ranged in carbon number from C55 to C25. The enzyme is constituted of two subunits of approximately 30,000 molecular weight. A radiolabeled photolabile analogue of t,t-farnesyl pyrophosphate, [3H]2-diazo-3-trifluoropropionyloxy geranyl pyrophosphate, was shown to label Lactobacillus plantarum and E. coli undecaprenyl pyrophosphate synthetase on UV irradiation in the presence of isopentenyl pyrophosphate and divalent cation. The only labeled polypeptide migrated on electrophoresis in a sodium dodecyl sulfate-polyacrylamide gel at a molecular weight of approximately 30,000. No protein was radiolabeled when the natural substrate, t,t-farnesyl pyrophosphate was included in the irradiation mixture. Irradiation in the presence of MgCl2 without isopentenyl pyrophosphate gave less labeling of the polypeptide. Irradiation with only isopentenyl pyrophosphate gave little labeling of the polypeptide. When the enzyme was irradiated with 3H-photoprobe, [14C]isopentenyl pyrophosphate, and MgCl2, the labeled polypeptide gave a ratio of 14C/3H that indicated the product must also bind to the enzyme on irradiation. These results demonstrate the ability to radiolabel the allylic pyrophosphate binding site and possibly product binding site of undecaprenyl pyrophosphate synthetase by a process which is favored when both cosubstrate and divalent cation are present.

Affinity Labels↗
PubMed1985

Ultrastructural cytochemistry of carbohydrates in microfibrils associated with the amorphous elastin in the monkey aorta.

Two distinct ultrastructural components of elastic fibers can be identified--namely, the amorphous elastin and the microfibrils. We have examined the tunica adventitia of monkey aortas to demonstrate differential localization of carbohydrates in elastic fibers and collagen fibrils using Thiéry's periodic acid-thiocarbohydrazide-silver proteinate (PA-TCH-SP) staining of thin sections for vicinal-glycol-containing complex carbohydrates, en bloc concanavalin A (Con A) staining specific for alpha-D-mannosyl and alpha-D-glucosyl groups, and en bloc wheat germ agglutinin (WGA) staining specific for N-acetyl-D-glucosamine, N-acetylneuraminic acid, and N-acetyl-D-galactosamine. The PA-TCH-SP method moderately stained microfibrils and weakly stained collagen fibrils, but did not stain the amorphous elastin. Both Con A and WGA staining methods strongly stained microfibrils and moderately stained collagen fibrils, whereas the amorphous elastin lacked staining. Thus PA-TCH-SP, Con A, and WGA staining methods allow differential ultrastructural localization of carbohydrates in elastic fibers and collagen fibrils in monkey aortic adventitia and demonstrate the presence of more carbohydrate components in microfibrils than in collagen fibrils, whereas amorphous elastin lacks carbohydrate staining.

Animals↗
PubMed1985

An inhibitory factor against monocyte spreading in the sera of patients with systemic lupus erythematosus.

The effect of the sera of patients with systemic lupus erythematosus (SLE) on monocyte function was studied using cell spreading as an indicator. Monocyte spreading induced by exogenous stimuli was shown to be inhibited by SLE sera. Gel filtration of SLE sera on Sephadex G-200 revealed that the factor responsible for this inhibition had a molecular weight of about 50,000. Pretreatment of monocytes with the inhibitory factor led to suppression of cell spreading induced by subsequent stimulation, but this hyporeactivity was reversible. Spreading of monocytes was rapidly aborted by the addition of this inhibitory factor. Thus, the inhibitory factor appeared to affect monocyte itself, but its effect seemed to be transient.

Cell Adhesion↗
PubMed1985

Inactivation of cis-diamminedichloroplatinum (II) in blood and protection of its toxicity by sodium thiosulfate in rabbits.

The mode of inactivation of cis-diamminedichloroplatinum(II) (DDP) in the bloodstream and protection from its toxicity by sodium thiosulfate (STS) were investigated in rabbits. Plasma ultrafiltrate in rabbits given 5 mg/kg DDP IV and various excess molar ratios of STS IV were assayed for the active platinum levels with a new microbiological assay system using an E. coli strain. The active platinum species in the plasma were inactivated completely by co-administration of a 400-fold excess of STS IV. The rabbits were almost completely protected against both BUN increase and body weight loss normally caused by DDP when 400-fold doses of STS were given. Diuretic effects were also observed. Our data provide evidence for the basis of optimum use of STS to protect against DDP toxicity.

Animals↗
PubMed1985

1H-2-Benzopyran-1-one derivatives, microbial products with pharmacological activity. Conversion into orally active derivatives with antiinflammatory and antiulcer activities.

A novel gastroprotective substance, 6-[[1(S)-[3(S),4-dihydro-8-hydroxy-1-oxo-1H-2-benzopyran-3-yl] -3-methylbutyl]amino]-4(S),5(S)-dihydroxy-6-oxo-3(S)-ammoniohexanoate (AI-77-B, 1), isolated from a culture broth of Bacillus pumilus AI-77, was chemically modified to prodrugs that are active by oral dosing. Compound 1 was lactonized and then monoalkylated at the primary amine position. Six N-alkylated gamma-lactone derivatives of 1 (with alkyl chains being methyl 5a, ethyl 5b, n-propyl 5c, n-butyl 5d, n-pentyl 5e, or n-hexyl 5f) were synthesized and eight compounds including 1 and gamma-lactone derivative 2 were compared for their gastroprotective activities and blood levels after oral administration in rats. Further, chloroform-water partition coefficients of 5a-f were also compared as a measure of lipid solubility. The protective effects of these compounds on stress ulcers were mutually related to blood levels of dealkylated compounds (1 and 2). Parent compound 1 was detected in blood at 1 h after each of 5a-d was administered. When 5b or 5c was administered, high activity and high blood levels of 1 were observed in comparison with those levels obtained with 5a or 5d. Neither 5e nor 5f were detected in any amount in blood by oral administration without special formulation due to extremely low solubilities and agglutinative properties in intestinal fluid. Interestingly, 5b and 5c were found to have antiinflammatory activities in addition to potent antiulcerogenicity action.

Administration, Oral↗
PubMed1985

Effects of ovarian hormones on manifestation of purulent endometritis in rat uteruses infected with Escherichia coli.

To assess the influence of hormones on uterine infections, Escherichia coli was infused into uterine lumens of ovariectomized or adrenoovariectomized rats receiving exogenous administration of various doses of ovarian hormones. Large numbers of E. coli were recovered from the rat uterine lumens, irrespective of hormonal influences. The number of leukocytes in the uterine flushings, representing the magnitude of purulent inflammation, differed significantly depending upon the hormonal regimen given to each host. Purulent endometritis was induced by E. coli in ovariectomized rats receiving progesterone or corn oil (hormone vehicle). Infections were asymptomatic in rats receiving estradiol, but promethazine-treated uterine horns were susceptible to infection. When progesterone was administered along with estradiol, purulent inflammation was caused by E. coli, but the number of leukocytes in the uterine lumens was significantly less than that obtained from the rats treated with progesterone or corn oil. These effects of ovarian hormones on uterine infections were observed in adrenoovariectomized rats as well as in ovariectomized rats. It is suggested that estradiol alters the nature of endometrial epithelium and prevent manifestation of purulent endometritis; progesterone antagonizes estradiol. Adrenal hormones appear not to participate in the pathogenesis of endometritis induced by E. coli.

Adrenalectomy↗
PubMed1985

In vitro adherence of Escherichia coli to endometrial epithelial cells of rats and influence of estradiol.

The influence of ovarian hormones on the adhesion of Escherichia coli to endometrial epithelial cells was investigated in an in vitro system. Endometrial cells liberated by collagenase from rat uteri were used. Optimal test conditions were obtained when 5 X 10(8) E. coli bacteria were added to 10(5) epithelial cells and incubated for 60 min. The adhesion of the organisms was inhibited by the addition of either mannose or alpha-methyl-D-mannopyranoside. When epithelial cells collected from uteri of estradiol-treated rats were used, the number of E. coli adhering to the cells was markedly lower than that adhering to epithelial cells collected from control rats. These results suggest that E. coli adheres to endometrial epithelial cells with so-called type 1 pili and that estradiol alters the nature of the endometrial epithelium and prevents the adherence of the organisms to the cells.

Animals↗