Search PubMed⌕ Search

Biomedical subjects

M Nohara

Publications and source records attributed to M Nohara.

At least 55 records · Page 3Linked to original sources
PubMed1991

Evaluation of DNA probe test for clinical diagnosis of chlamydial and gonococcal infections of the uterine cervix.

A DNA probe test (Gen-Probe) was compared with cell culture and an enzyme immunoassay method (Chlamydiazyme) for the clinical diagnosis of cervical chlamydial infection. A total of 127 specimens (95 before treatment and 32 after treatment) were obtained from 95 patients considered members of a high risk population. Forty-five (47.4%) of the 95 cases examined before treatment were positive for the DNA probe and the sensitivity, specificity, positive predictive value and negative predictive value of the test vs cell culture were 78.4, 93.4, 88.9, and 86.6%, respectively. Comparison of these data with those of Chlamydiazyme showed that the DNA probe method was a little less sensitive but much more specific. The kit could also detect gonococcal infection with sufficient accuracy in the same specimen as used for Chlamydia trachomatis, and was considered to be a useful tool as another noncultural alternative for clinical diagnosis of sexually transmitted chlamydial and gonococcal infections of the uterine cervix, although further improvement on the kit for Chlamydia trachomatis is expected.

Adolescent↗
PubMed1989

Electrophysiological properties of cultured dog myocytes obtained by endomyocardial biopsy.

Right ventricular cardiac tissue (10-20 mg wet weight) was obtained from anesthetized adult dogs by endomyocardial biopsy. The biopsy could be repeated in one dog every 2 weeks for up to 3 months. Fifty to 200 cardiomyocytes, dispersed with collagenase and trypsin, were collected by centrifugation of the cells with 50% polysucrose-sodium diatrizoate solution (Ficoll-Paque). Single cardiomyocytes were suspended in a minimum essential medium containing 20% fetal bovine serum and 8-bromoadenosine 3': 5'-cyclic monophosphate (0.1 mM) for up to 3 weeks. Approximately 70-80% of the cultured cardiomyocytes were rod shaped after 24 hours (10-20% after 7 days). Cytoplasmic organelles of the cultured cells, examined with a transmission electron microscope, were within the normal range of canine heart morphology in vivo. Resting membrane potential of the cells was about -80 mV when superfused with a Krebs' solution containing 4.7 mM potassium ions. The action potential lasted for 300 msec and had a peak amplitude of about 120 mV. Voltage-clamp experiments demonstrated the presence of an inward calcium current (congruent to 0.9 nA at +9 mV), which was facilitated by isoproterenol (0.1-1 microMs). The background potassium current showed typical inward rectification at potentials more negative than -80 mV. The results indicate that morphological, electrophysiological, and pharmacological properties of the cultured cardiomyocytes were intact. We propose that the culture techniques we have developed can be useful for repeated investigation on functional aspects of cardiac muscles in myocardial disease.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1985

High-performance liquid chromatographic determination of N1-alkylnicotinamide in urine.

A simple high-performance liquid chromatographic method has been developed for determining N1-alkylnicotinamides, including C1-C5 alkyl derivatives, in urine. N1-Alkylnicotinamides were reacted with acetophenone in strong alkali medium at 0 degrees C and then formic acid was added. The reaction mixture was heated in acidic medium at above 93 degrees C, and the fluorescent product, 1-alkyl-7-phenyl-1,5-dihydro-5-oxo-1,6-naphthyridine, was chromatographed by HPLC, using a Zorbax SCX-300 column with a mixed mobile phase of acetonitrile-0.04 M ammonium phosphate, monobasic. N1-Alkylnicotinamides can be determined as 1,6-naphthyridine derivatives by a fluorometric detector at a level of 100 pg (signal/noise = 2). Recoveries of N1-alkylnicotinamides in urine were satisfactory. Interfering reaction products from NAD+ and NADP+ were clearly eliminated for determination of N1-alkylnicotinamides without pentyl derivatives.

Adult↗
PubMed1985

Relationship between mutagenic potency in Salmonella typhimurium and chemical structure of amino- and nitro-substituted biphenyls.

All positional isomers of mononitro- and monoaminobiphenyls and those of dinitro-, diamino- and aminonitrobiphenyls, which have one substituent on each benzene ring, were assayed for mutagenicity in Salmonella typhimurium by the Ames method. The results suggest that the structural requirements favoring mutagenic activity are the presence of substituents at the 4-position and their absence at the 2'-position. The introduction of an amino group to the 3'- or 4'-position of 4-nitrobiphenyl or a nitro group to 3'- or 4'-position of 4-aminobiphenyl enhanced the mutagenicity. Among the mutagenic compounds, 4-nitro analogues were mutagenic in strains TA98 and TA100 in the absence of a microsomal metabolic activation system. Strain TA98NR was not reverted by the direct-acting mutagens, whereas strain TA98/1,8-DNP6 was as revertible as strain TA98; these results suggest that the direct-acting mutagenicity involves the reduction of the nitro group by bacterial nitroreductase but does not involve specific esterification enzymes.

Biphenyl Compounds↗
PubMed1985

The effect of quercetin on the mutagenicity of 2-acetylaminofluorene and benzo[alpha]pyrene in Salmonella typhimurium strains.

The comutagenic and desmutagenic effect of quercetin on the mutagenicity of typical mutagens e.g. 2-acetylaminofluorene (AAF), 4-nitroquinoline-1-oxide (4NQO) and benzo[alpha]pyrene (B[a]P), in Salmonella typhimurium TA98, TA100 and TA98/1,8 DNP6 were examined. In the mixed application of AAF with quercetin in the presence of mammalian metabolic activation system (S9 mix), the numbers of revertants in TA98 increased by as much 2.2-5.0-fold compared with the sum of those in the separate applications of AAF and quercetin. A 1.4-2.7-fold increase was observed in TA100. Quercetin did not affect the mutagenicity of 4NQO, and depressed that of B[a]P. Dose-response curves for mutagenicity of quercetin with or without AAF (5 micrograms/plate) were examined. The results suggest that quercetin, present in a molarity of up to 1.5 times that of AAF, is apparently effective in enhancing the mutagenicity of AAF, because a linear dose-response curve was observed in the range of 0-5 micrograms/plate quercetin with AAF although quercetin alone was not mutagenic in the same range. Dose-response curves for mutagenicity of quercetin with or without 5 micrograms/plate B[a]P did not increase compared with that for quercetin alone. The mutagenicity of the mixed application of B[a]P with quercetin was reduced to about 60% of the sum of separate application at doses ranging from 25 to 100 micrograms/plate of quercetin. Since enhancement and depression of mutagenicity by quercetin were observed for indirect mutagens, AAF and B[a]P, respectively, in the presence of S9 mix, quercetin may affect the metabolic pathway of these mutagens.

2-Acetylaminofluorene↗
PubMed1984

Meningoencephalitis due to serratia marcescens infection in neonates.

Six autopsy cases of Serratia meningoencephalitis were reported. The symptoms of this infection become apparent at an early stage in neonates; the meningoencephalitis in these six cases was severe, with or without inflammatory lesions in other organs. Serratia marcescens was originally described as a nonpathogenic organism; however, it is believed that after entering the blood stream of neonates, it becomes pathogenic, especially to the central nervous system. Meningoencephalitis due to Serratia marcescens is very severe and takes a rapid and progressive course against which no antibiotics have been found effective. Prevention of this infection is therefore considered of crucial importance.

Cerebrospinal Fluid↗
PubMed1984

Angiogenesis of cultured endothelial cells of bovine coronary artery.

Endothelial cells of bovine coronary artery were isolated and cultivated and bovine clots were placed in the cultured endothelial cells (42 generations), followed by observation on the 14th day. Cultured endothelial cells not only covered the surface of each clot but also migrated in it to form oval or irregularly shaped intracytoplasmic vacuoles or sometimes intercellular vacuoles surrounded by 2 or 3 cells. Some of these vacuoles contained membranous materials. This vacuolization was considered to represent angiogenetic activity peculiar to endothelial cells.

Animals↗
PubMed1983

Perianal alveolar rhabdomyosarcoma in a child. Report of a long-term survival case.

The long-term survival of alveolar rhabdomyosarcoma of the perianal region in a 13-month-old infant is described. Local excision with chemotherapy consisting of vincristine, actinomycin D, and cyclophosphamide over a period of two years has resulted in eight years of tumor-free survival with normal growth and development. Our case and review of the literature suggest that local excision with chemotherapy may be an appropriate treatment for Group I perianal rhabdomyosarcoma in children.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1983

Mutagenicity of coal-pyrolyzed products and their photochemical reaction products with nitrogen oxides in Salmonella typhimurium TA98 and TA100.

The chemical class separation of coal-pyrolyzed products and the photochemical reaction of these fractions with nitrogen oxides in the experimental chamber, and the application of a short-term mutagenicity test were investigated. The altered products from the fraction hydroxy polycyclic aromatic compounds in a simulated atmosphere containing a small volume of nitrogen oxides under irradiation with a xenon lamp were the most potent mutagenic fraction among all the fractions tested against Salmonella typhimurium, both TA98 and TA100, with or without S9.

Animals↗
PubMed1983

High performance liquid chromatographic determination of malondialdehyde in vegetable oils.

A simple high performance liquid chromatographic (HPLC) method has been developed for determining malondialdehyde (MDA) in vegetable oils. MDA was reacted with dansyl hydrazine in an acidic medium, and the product, 1-dansyl-pyrazole, was determined by HPLC, using a Zorbax sil column with mixed mobile phase of n-hexane-methylene chloride. MDA can be determined as 1-dansyl-pyrazole by fluorometric detection at a level of 0.01 ppm in vegetable oils.

Chromatography, High Pressure Liquid↗