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Biomedical subjects

H Onodera

Publications and source records attributed to H Onodera.

At least 253 records · Page 14Linked to original sources
PubMed1989

Teratoma of the pituitary gland in a young male rat.

A pituitary teratoma was found in a 5-week-old (37-day-old) male Donryu rat. The tumour (10 x 11 x 9 mm) was round in shape and white in colour. The cut surface was solid without haemorrhagic or cystic change. Histologically, it was composed of various kinds of tissue components including mature and immature elements derived from the three embryonic germ layers, i.e., nervous tissue, cartilage, bone, squamous epithelial element, glandular element lined by one or more layers of ciliated columnar or cuboidal epithelial cells, striated muscle tissue, adipose tissue and connective tissue. Neuroepithelial rosettes and immature or embryonal epithelium as well as immature cartilage were intermingled with mature somatic tissues.

Animals↗
PubMed1989

Excitatory amino acid binding sites in the rat hippocampus after transient forebrain ischemia.

The influence of transient forebrain ischemia on the temporal alteration of glutamate receptors in the hippocampal formation was analyzed by means of in vitro quantitative receptor autoradiography. We compared the binding of N-methyl-D-aspartate (NMDA) receptors using [3H]3-[+/-)2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP), noncompetitive NMDA antagonist binding sites using [3H]N-(1-(2-thienyl)-cyclohexyl)-3,4-piperidine (TCP), and kainate (KA) receptors. In the CA1 subfield of the hippocampus, the number of NMDA receptors and noncompetitive NMDA antagonist binding sites remained constant during the early stage of recirculation when the CA1 pyramidal cells remained histologically intact. A significant reduction of these receptor densities was observed 7 days following ischemia, when NMDA receptors and noncompetitive NMDA antagonist binding sites lost 64 and 29% of their binding sites in the stratum radiatum of the CA1, respectively. The KA receptor density in the CA1 subfield decreased by 44% 7 days after ischemia. Marked loss of the above-mentioned receptors in the CA1 after selective depletion of the CA1 pyramidal cells indicated that NMDA receptors, noncompetitive NMDA antagonist binding sites, and KA receptors in the CA1 are predominantly localized on the CA1 pyramidal cells. NMDA receptor density in the CA3 gradually decreased during the recirculation period. The stratum moleculare of the dentate gyrus, whose structure was histologically intact after ischemic insult, also showed a reduction of NMDA receptors 7 days following ischemia. [3H]KA receptor density in the stratum lucidum of the CA3 and in the hilus also decreased during recirculation. These

Amino Acids↗
PubMed1989

Dose-response carcinogenicity in rats on low-dose levels of N-ethyl-N-nitrosourethane.

A dose-response study on the carcinogenicity of N-ethyl-N-nitrosourethane (ENUR) was undertaken to examine its effect at low doses. Six-week-old female F344 rats were divided into 5 groups, each consisting of 40 animals. ENUR was dissolved in distilled water at dose levels of 0 (control), 0.15, 0.6, 2.5 and 10 ppm, and rats were given these solutions ad libitum for 2 years. Significant increase of the total tumor incidences and shortening of the mean survival times were observed in groups given 2.5 and 10 ppm ENUR. In groups given 0.6 ppm or more ENUR, digestive tract tumors were induced dose-dependently. They were restricted to the upper digestive tract from the oral cavity to the forestomach, and were histologically squamous cell papillomas or carcinomas. Dose-related differences in the location and incidence of these tumors were found. The virtually safe doses (VSDs) calculated by using the Weibull, Logit and Probit models were 0.365 x 10(-2), 0.110 x 10(-1) and 0.779 x 10(-1) ppm, respectively. The VSDs estimated in the present study are discussed in comparison with those of other carcinogens.

Administration, Oral↗
PubMed1989

[Clinical study of combination chemotherapy with mitomycin C, vindesine and cisplatin (MVP therapy) in advanced non-small cell lung cancer].

Thirty-seven patients with inoperable non-small cell lung cancer were treated with the combination chemotherapy (MVP therapy) with mitomycin C (8 mg/m2), vindesine (3 mg/m2 X 2) and cisplatin (60 mg/m2). The partial responders were 13 cases (35%), and the median survival time was 271 days. In this study the cisplatin dose was less than in any other report of "MVP" therapy. But both the response rate and the median survival time did not differ from those reported elsewhere. The side effects (bone marrow suppression, renal toxicity, etc.) were mild, and did not prevent the continuance of this therapy. Thus, we could repeat more than 6 courses of "MVP" therapy for 8 patients. Nowadays, it is difficult to obtain complete responders with any chemotherapy for inoperable non-small cell lung cancer. To prolong lives of patients and maintain good quality of life, we recommend chemotherapy with low toxicity in often-repeatable courses.

Adult↗
PubMed1989

[Effect of blood transfusion on prognosis of colorectal cancer patients].

To evaluate the effect of blood transfusion on prognosis of colorectal cancer, data of 592 patients having been operated on in our department were analyzed using Cox method, logistic regression and Mantel-Haenszel test. The predictor variables were age, tumor location, Turnbull's modification of Dukes stage, preoperative hemoglobin (HB), anesthetic time (AT), perioperative blood transfusion (BT), and intraoperative blood loss (BL). Cox analysis showed that the most significant prognostic factors were Stage and BT (p less than 0.001), followed by location and BL. Logistic analysis also revealed that Stage and BT were significant predictors of 1-year and 5-year survivals. Similar results were obtained by Mantel-Haenszel test in which the patients were stratified by Stage, and grouped by HB, BT and BL. BT was a significant factor whereas BL and HB did not achieve statistical significance. We conclude that BT is an important prognostic factor unrelated to other variables and its adverse effect on survival is of higher significance than BL and HB. Some measures including clinical decision analysis were proposed to avoid unnecessary blood transfusion in surgery.

Colorectal Neoplasms↗
PubMed1989

[Subchronic oral toxicity study of calcium lactate in F344 rats].

A subchronic toxicity study of calcium lactate was carried out in male and female F344 rats to estimate the maximum tolerated dose for a subsequent long-term toxicity/carcinogenicity study. Experiment I: Rats were divided into 6 groups, each consisting of 5 males and 5 females. Calcium lactate was dissolved in water at concentrations of 5, 2.5, 1.25, 0.6, 0.3 and 0%, each animal group was given one of these solutions as the drinking water for 13 wk. In all groups, basic diet (CRF-1) was given ad libitum. No fatalities occurred. In all treated groups, including the 5% group, a less than 10% depression of body-weight gain as compared with the control group was observed. Some parameters in the hematological and biochemical data demonstrated change in the treated groups. On histological examination, however, no severe toxicological findings were found in any of the treated groups. Experiment II: Rats were fed synthetic diet B, containing 30, 20, 10, 5 or 0% calcium lactate. In the highest dose group, body weight-gain was strongly reduced as compared with the control group. Histological examination revealed nephrocalcinosis in all groups, including the control group, and adverse dose-effect relation was observed with regard to degree of its development. Females exhibited this lesion to a greater extent than males. Experiment III: Rats were given CRF-1 or synthetic diet B for 8 wk. Nephrocalcinosis was found only in the group given synthetic diet. It was ascertained that the nephrocalcinosis observed in Exp. II and III was dependent on the low Ca/P ratio (Ca/P: less than 1) of the synthetic diet B.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

[A case of huge duodenal leiomyosarcoma].

A case of duodenal leiomyosarcoma with large central necrosis was reported. Tumor was 15 X 10 X 10 cm in size. Ultrasonography showed a cystic tumor with thick wall in the right upper abdomen. CT scan revealed a gas formation in the central cystic cavity of the tumor. The gas formation was probably caused by bacterial infection. The diagnosis was confirmed histologically.

Aged↗
PubMed1989

[A case of pseudolymphoma of the lung with cough and fever].

This case report presents a 48-year-old woman who had been suffering from cough and fever for 5 years. A large mass in the right lung was pointed out. Even after various examinations, we couldn't resolve the difficult diagnostic problems involved, but it was clear that there were no signs of a malignant tumor. We suspected a large benign tumor or pulmonary sequestration. Right lower lobectomy was performed and histological examinations of the resected tumor revealed lymphoproliferative disorder. Microscopic examinations of the specimen disclosed monotonous lymphoid cells proliferation (small to medium size) without definite lymph follicles or germinal centers. Lymph follicles were clearly demonstrated with the immunoperoxidase method. These findings were interpreted to be consistent with what has been recently called pseudolymphoma of the lung and prompted discussions on the reasonableness of criteria for the diagnosis of various pseudolymphoma and effective immunological examinations for the clarification of the etiology.

Complement System Proteins↗
PubMed1988

Differential localization of adenosine A1 receptors in the rat hippocampus: quantitative autoradiographic study.

[3H]Cyclohexyladenosine ([offCHA) was used to label adenosine A1 receptors in the rat hippocampus by quantitative autoradiography, and selective lesions in the neurons intrinsic to CA1 and CA3 subfields were chemically produced to determine the cellular localization of A1 receptors. Lesioning the CA3 subfield by intracerebroventricular kainic acid injection caused a 50% reduction in the maximal binding capacity of [3H]CHA in the CA3 subfield with no alteration in binding affinity. Five days after unilateral CA3 lesioning, a reduction of [3H]CHA binding by 10-30% of ipsi- and contralateral was observed in the dendritic fields in the CA1 region, though a significant reduction was restricted to the ipsilateral stratum radiatum. Thirty-five days after CA3 lesioning, [3H]CHA binding in the stratum radiatum in the CA1 subfield ipsilateral to the CA3 lesion revealed a small reduction in Bmax values but no alteration in Bmax in other sublayers of the CA1. The Kd values in all regions of the hippocampus were not different from the control values. Selective CA1 pyramidal cell lesioning by transient ischemia caused a 70% reduction of [3H]CHA binding sites in the CA1 subfield. Neither CA1 nor CA3 lesions altered [3H]CHA binding in the stratum moleculare of the dentate gyrus. These results suggest that only a small population of adenosine A1 receptors are associated with the terminals of the CA3 pyramidal cells (Schaffer collaterals and commissural fibers) in the CA1 subfield. A1 receptors in the CA1 and CA3 subfields are predominantly located on intrinsic pyramidal cells.

Adenosine↗
PubMed1988

The effect of transient ischemia on 2-[14C]deoxyglucose metabolism in the rat hippocampus pretreated with kainic acid.

CA1 pyramidal neurons are selectively vulnerable to ischemia. 2-[14C]Deoxyglucose (2-DG) autoradiography was employed to measure local glucose utilization in the rat hippocampus after transient ischemia, under the condition of unilateral prevention of ischemic CA1 pyramidal cell necrosis by unilateral lesioning of Schaffer collaterals (left side). Columnar 2-DG uptake patterns in the CA1 region with intact Schaffer collaterals (right side) was observed 19-22 h after recirculation, though no laterality was noted 3 and 8 h after recirculation. In the right subiculum, higher 2-DG uptake was observed 19-22 h after recirculation in 5 out of 8 animals. These results suggest that Schaffer collaterals play a role in modulating glucose metabolism in the CA1 and subiculum during recirculation.

Animals↗
PubMed1988

Carcinogenicity and organ specificity of N-trimethylsilylmethyl-N-nitrosourea (TMS-MNU), N-neopentyl-N-nitrosourea (neoPNU), and N-methyl-N-nitrosourea (MNU) in rats.

The carcinogenicity and organ specificity of TMS-MNU and neoPNU, a carbon-analogue of TMS-MNU, in rats were investigated and compared with those of MNU. Compounds were dissolved in olive oil and rats in the experimental groups received 20 weekly intragastric intubations of 10 mg/kg of MNU or equimolar amounts of TMS-MNU or neoPNU in the same manner. The experiment was terminated when the survivors were sacrificed at the 52nd week after the final administration. In the TMS-MNU and MNU groups, tumors of the forestomach were induced and the incidence was 100% in the groups of both sexes. In addition, tumors of the glandular stomach, nervous system, kidney, and lung were also observed in these groups. Neurogenic tumors were found more frequently in the MNU group than in the TMS-MNU group. The incidence of lung tumors, however, was higher in the TMS-MNU group than in the MNU group. On the other hand, in the control and neoPNU groups, no tumor was found in these organs except the lung, and all tumors observed in these two groups were histologically similar to spontaneous ones in this strain of rats. These results indicate that the carcinogenicity of N-alkyl-N-nitrosoureas is dependent on the chemical structure of their alkyl chain. The result of the present study coincides with the previous result that the species of TMS-MNU in the alkylating step is the same as that of MNU, but different from neoPNU. The difference in the organ specificity between TMS-MNU and MNU demonstrates that the organ specificity is dominantly dependent on the distribution of the chemicals, since TMS-MNU may possibly be distributed differently from MNU because of its different partition property.

Animals↗
PubMed1988

Neurotransmitter receptors of the rolling mouse Nagoya: a quantitative autoradiographic study.

The distribution of neurotransmitter and neuromodulator receptors was studied in the brain of the rolling mouse Nagoya (RMN) and in controls, using in vitro receptor autoradiography. Quantitative autoradiography was used to map adenosine A1 (labeled with [3H]cyclohexyladenosine), GABAA [( 3H]muscimol), opiate [( 3H]naloxone), L-glutamate [( 3H]L-glutamate), benzodiazepine [( 3H]flunitrazepam), and muscarinic cholinergic [( 3H]quinuclidinyl benzilate) receptors. In the cerebellar cortex, GABAA and adenosine A1 binding sites were significantly reduced in the RMN, whereas other transmitter binding sites were not significantly altered. Adenosine A1 binding sites were also reduced in the cerebral cortex and caudate-putamen. Benzodiazepine binding was significantly decreased in the cerebral cortex and increased in the CA1 subfield of the hippocampus. These results suggest that neurochemical alterations in the caudate-putamen as well as in the cerebellar cortex play important roles in the ataxia and motor dysfunction of the RMN.

Animals↗
PubMed1988

Autoradiographic localization of opioid and spirodecanone receptors in the gerbil hippocampus as compared with the rat hippocampus.

Opioid ([3H]naloxone) and spirodecanone ([3H]spiperone) binding sites in the hippocampus were visualized in the Mongolian gerbil and in the rat using in vitro autoradiography. In the hippocampus, marked differences were noted in the stratum (sr.) pyramidale of the CA1 subfield where opioid and spirodecanone (assayed in the presence of mianserin and sulpiride) binding activities were very low in gerbils, but high in rats. Gerbils exhibited a high concentration of [3H]naloxone binding sites in the sr. pyramidale of the CA3 subfield, as observed in the rat. In addition, the gerbil has a very high opioid receptor density in the hilar region and in the sr. moleculare of the dentate gyrus. The cellular localization of opioid and spirodecanone receptor sites was studied in the rat hippocampus using selective neuronal damage to CA1 and CA3 neurons by means of ischemia and kainic acid treatment, respectively. The results suggest that the gerbil differs from the rat with respect to the characteristic pyramidal cells (spirodecanone binding site) and interneurons (opioid receptor) in the CA1 subfield of the hippocampus. Distinct localization of opioid and spirodecanone receptors in the gerbil provides a good model with which to investigate the electrophysiological and biochemical roles of opioid peptides and butyrophenone spirodecanone drugs.

Animals↗
PubMed1988

Effects of active oxygen scavengers on the peroxidation of linoleic acid catalyzed by dehydro-L-ascorbic acid or its degradation products.

The addition of 1,4-diazabicyclo-[2,2,2]octane (DABCO) (100 mM) or 1,2-dihydroxybenzene-3,5-disulfonic acid (Tiron) (1 mM) to a reaction mixture containing 10 mM linoleic acid (LA), 20% EtOH, and 135 microM dehydroascorbic acid (DHA) as a catalyst suppressed LA peroxidation, but the addition of mannitol (approximately 100 mM), uric acid (100 microM), and catalase (6.5 units) did not. DHA or 2,3-diketo-L-gulonic acid (DKG) accelerated LA peroxidation, but the splitting products of DHA did not affect LA peroxidation. These results suggest that some specific radicals are liberated in the degradation of DHA or DKG.

1,2-Dihydroxybenzene-3,5-Disulfonic Acid Disodium ↗