Search PubMed⌕ Search

Biomedical subjects

N Ueda

Publications and source records attributed to N Ueda.

At least 469 records · Page 26Linked to original sources
PubMed1982

Chemoreceptors for serotonin (5-HT), acetylcholine (ACh), bradykinin (BK), histamine (H) and gamma-aminobutyric acid (GABA) on rabbit visceral afferent neurons.

The somata of type 'C' neurons in rabbit nodose ganglion are endowed with receptor sites for 5-HT, BK, ACh, II and GABA. 5-HT and ACh application to type 'C' neurons in the nodose ganglion of rabbits produced a rapid depolarization associated with an increased membrane conductance, most likely to Na+ and K+. BK and H elicited slow depolarizations accompanied by a decreased membrane conductance probably to K+. GABA induced a rapid depolarization associated with an increased conductance to Cl-. In contrast, type 'A' neurons were insensitive to the four algesic agents but responded to GABA. d-Tubocurarine or picrotoxin at relatively low concentrations blocked ACh, 5-HT and GABA depolarizations without affecting membrane properties. Hexamethonium blocked ACh responses but not 5-HT responses. In addition, no desensitization occurred between the substances 5-HT, ACh or BK. The results suggest that the depolarizing effect of these agents on visceral neurons might be exerted via different receptors.

Acetylcholine↗
PubMed1982

Specific induction of erythroleukemia and myelogenous leukemia in Sprague-Dawley rats.

The experimental induction of leukemias of two sorts by two powerful chemical carcinogens was investigated in rats of a single strain. In Sprague-Dawley rats a series of intravenous injections of N-nitroso-N-methylurea selectively elicited myelogenous leukemia in high yields, whereas erythroleukemia was not evoked. Conversely, a set of intravenous injections of 7,8,12-trimethylbenz[a]anthracene specifically elicited erythro-leukemia in high incidence in the rats, whereas myelogenous leukemia was not produced.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1982

Suppression of 7,12-dimethylbenz[a]anthracene-induced chromosome aberrations in rat bone marrow cells after treatment with Sudan III and related azo dyes.

Noninbred Long-Evans rats fed Sudan III at 24 hours before they were given an injection of 7,12-dimethylbenz[a]anthracene (DMBA) displayed prominently suppressed DMBA-induced chromosome aberrations (CA) in their bone marrow cells. Rats fed Sudan III simultaneously with the DMBA injection showed no suppressed CA effect. The suppressive effect of Sudan III on DMBA-induced CA paralleled the dose rate of Sudan III when given in the range between 1 and 10 mg Sudan III/kg body weight; higher doses produced no additional suppression. The capacity of various Sudan III-related chemicals to prevent DMBA-induced CA paralleled their capacity to prevent DMBA-induced adrenal apoplexy and mammary cancer. Among the azo dyes investigated, Sudan III was most efficient in protecting against DMBA-induced CA. Polychlorinated biphenyl and phenobarbital, inducers of drug-metabolizing enzymes, also suppressed DMBA-induced CA.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1982

[Clinical effects of netilmicin].

In the present study, we used netilmicin for the postoperative complications and obtained the following results. 1. Netilmicin was used in totally 29 cases; 23 with localized peritonitis, 4 with generalized peritonetis and 2 with wound infection. Excellent effects were obtained in 2 cases, effective results in 24 cases and ineffective results in 3 cases. The effective rate was 89.7%. 2. Adverse reactions or abnormal clinical laboratory test results which might be attributable to the use of netilmicin were not noticed.

Adult↗
PubMed1981

N-Nitroso-N-methylurea elicits mammary cancer in resistant and sensitive rat strains.

A single intravenous (i.v.) injection of the water-soluble mammary carcinogen N-nitroso-N-methylurea (NMU; 35 mg/kg of body weight) elicited cancer of the breast in young female rats of two strains in the following incidence: Long-Evans strain, 4%; Sprague-Dawley strain, 70%. In sisters of these rats, a set of 5 i.v. injections of NMU (35 mg/kg at biweekly intervals) evoked mammary carcinoma as follows: Long-Evans strain, 76%; Sprague-Dawley strain, 100%. In its effectiveness in evoking mammary cancer in Sprague-Dawley rats, the lipid-soluble mammary carcinogen 7,8,12-trimethylbenz[a]anthracene exceeded NMU in rapidity of development of cancer and in tumor yield.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1981

Supravital observation of in vitro basophils in immunological reactions.

The migration velocity and morphology of basophils in vitro were examined after the addition of anti-immunoglobulin (anti-IgE or anti-IgG). In atopic asthma patients with high serum IgE levels (more than 1000 i.u./ml) basophils showed increased migration velocity and showed pear-shaped and palmate processes after the addition of anti-IgE, but on the addition of anti-IgG, these basophils did not show increased migration velocity or morphological changes. In intractable asthma patients with low serum IgE levels, these changes occurred with anti-IgG but not with anti-IgE. These in vitro findings suggest a basophil reactivity to anti-IgE and anti-IgG in individual patients and support our previous differentiation of asthma patients according to basophil reaction.

Antibodies, Anti-Idiotypic↗
PubMed1981

Noncholinergic, nonadrenergic contraction and substance P in rabbit iris sphincter muscle.

In the rabbit iris sphincter muscle, electrical transmural stimulation produced fast and slow components of contraction which were markedly attenuated by tetrodotoxin. The fast component was augmented by physostigmine and was abolished by atropine, while the slow component was little affected. Adrenergic and ganglionic blocking agents did not inhibit the slow component. Therefore, the fast component is probably cholinergic, while the slow one is noncholinergic, nonadrenergic in nature. Capsaicin did produce a considerable contractile response, but there was a gradual decline with repetitive application and a tachyphylaxis occurred. Under such conditions the slow but not the fast component was abolished. Substance P and acetylcholine produced the largest contraction, while ATP, histamine, serotonin and noradrenaline produced little or no response. In cold stored preparations, the responses to electrical transmural stimulation and capsaicin were either markedly attenuated or abolished, whereas substance P and acetylcholine produced considerable contractions. Baclofen and theophylline did not inhibit the slow response to electrical transmural stimulation or the response to substance P and capsaicin. Thus, electrical transmural stimulation produces cholinergic and noncholinergic, non-adrenergic contractions in the rabbit iris sphincter muscle and the latter response is considered to be mediated by substance P or a related peptide released from the neural component.

Acetylcholine↗
PubMed1981

Hormone dependency of chromosome aberrations induced by 7,12-dimethylbenz[a]anthracene in rat bone marrow cells: site-specific increase by erythropoietin.

The frequency of chromosome aberrations (CA) 6 hours after iv injection of 50 mg 7,12-dimethylbenz[a]anthracene (DMBA)/kg was studied in bone marrow cells of the noninbred Long-Evans rat under various hematopoietic conditions. The percentage of metaphase cells with CA was enhanced by anemia and suppressed by polycythemia. The low incidence of CA in polycythemic rats was reversed by 6 U of sheep erythropoietin (EP) injected at the time of DMBA treatment. The interchromosomal and intrachromosomal distribution of CA indicated that hematopoietic stimuli, more specifically EP, greatly enhanced DMBA-induced CA in specific chromosomal regions.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1981

Chemical carcinogenesis in the rat: common mode of action of carcinogens at the chromosome level.

The chromosomal distribution of chromosome aberrations (CA) and sister chromatid exchanges (SCE) induced by various chemical carcinogens such as 7,12-dimethylbenz[a]anthracene, 7,8,12-trimethylbenz[a]anthracene, 1-butyl-1-nitrosourea, urethan, 4-nitroquinoline 1-oxide, 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide, and the antineoplastic compound mitomycin C was studied with the use of noninbred Long-Evans male rat bone marrow cells in vivo and in vitro. The CA and SCE induced by these structurally different chemicals were distributed in a similar pattern among and along chromosomes when the chemicals were given a short time (6 hr) before the metaphase cells were harvested. The specific distribution pattern of chemically induced CA and SCE along chromosomes was attributed to the late DNA replication of the vulnerable chromosome regions. Conversely, X-ray-induced CA were distributed more randomly. Thus the different chemical carcinogens were shown to exert a similar genetic effect at the chromosome level.

Animals↗
PubMed1981

[Evaluation of pancreatic scintigram in the diagnosis of pancreatic diseases (author's transl)].

The classification of accumulative patterns with the pancreatic scintigram findings of chronic pancreatitis and carcinoma of the pancreas were compared with endoscopic retrograde pancreatography (ERP) findings and Pancreozymin-Secretin test (P-S test). I) The frequency of pancreatic cancer was 93%, whilst, the chronic pancreatitis was 88% in the abnormal pancreatic scintigram. II) In the scintigram the type II (localized defect shadows) of pancreatic cancer was comparatively high and it is proportional to evidence derived from ERP. Localized diagnostic certainty is helpful, although the two tests are related. The P-S test is only restricted to the carcinoma of head, whilst, scintigram is more useful to detect the carcinoma of the body and tail of the pancreas. II) As for the chronic pancreatitis, there are various accumulative patterns. This is resemblance to that of ERP findings, but in the P-S normal test, it showed discrepancy in part of the result. Particularly, in the type I (slightly generalized low uptake with density silhouette) and type II. Therefore in order to obtain an accurate diagnosis, it is essential to have both the P-S test and scintigram.

Cholangiopancreatography, Endoscopic Retrograde↗