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Biomedical subjects

N Ueda

Publications and source records attributed to N Ueda.

At least 433 records · Page 24Linked to original sources
PubMed1984

Acute cytogenetic effect of sterigmatocystin on rat bone-marrow cells in vivo.

The acute cytogenetic effects of sterigmatocystin (SC) on rat bone-marrow cells in vivo were studied. The incidence of chromosome aberrations in bone-marrow cells increased and reached the maximum level at 12 h after an intraperitoneal injection of 10(-1) mM(31.2 mg)/kg body weight of SC and decreased gradually to the original level after 96 h. A dose-response relationship was observed between the dose of 10(-6) and 1 mM. The chromosome aberrations consisted of chromatid breaks and gaps, the distribution of breaks and gaps within chromosomes (Nos. 1 and 2) was similar to that induced by a carcinogen, 7,12-dimethyl-benz[a]anthracene.

Animals↗
PubMed1984

Enzyme histochemical studies on transplantable pancreatic adenocarcinomas in Syrian golden hamsters.

Transplantable pancreatic adenocarcinomas were established in subcutaneous tissue of Syrian golden hamsters and examined by enzyme histochemistry. The original tumors were found at week 40 after subcutaneous injection of N-nitrosobis(2-hydroxypropyl)amine (DHPN) at a dose of 250 mg/kg body weight once a week for the first 20 weeks of the experiment. They were well differentiated adenocarcinomas and their histology was not changed by serial transfer for 18 generations. Their transplantability was 67 to 100% and their average doubling time was 4.1 +/- 0.82 d. The enzymes gamma-glutamyl transpeptidase (GGT), lactate dehydrogenase (LDH), succinate dehydrogenase (SDH), alkaline phosphatase (ALPase), and acid phosphatase (ACPase) were examined in tumor cells at the 14th and 15th generations and in ductal cells and acinar cells of normal pancreas of hamsters. Increased GGT activity was found in the tumor cells, and a strongly positive reaction was observed in acinar cells but not ductal cells of normal pancreas. LDH and SDH were found in the tumor cells, acinar cells and ductal cells. No ALPase was detected in the tumor cells, acinar cells, or ductal cells. ACPase was found in acinar cells and ductal cells, but not in the tumor cells.

Adenocarcinoma↗
PubMed1984

Regression of myelocytic leukemia in rats after hypophysectomy.

A standard series of five intravenous injections of N-nitroso-N-methylurea (NMU) elicited selective patterns of neoplasms in male rats of the Sprague-Dawley strain; the neoplastic pattern was related to the age of the recipients. When the injections of NMU were started in weanling male rats, a specific triad of neoplasms developed that consisted of mammary carcinoma, primary myelocytic leukemia, and ear duct cancer. When the injections of NMU were started in males at age 100 days, a specific dyad of neoplastic growths was evoked that consisted of primary myelocytic leukemia and ear duct cancer, whereas mammary cancer and other neoplasms were not evident. Secondary myelocytic leukemia and myelocytic sarcoma were produced when blood from the foregoing rats with advanced primary myelocytic leukemia was injected in a subcutaneous site in newborn allogeneic rats. In a proportion of animals, primary and secondary myelocytic leukemia and myelocytic sarcoma underwent dramatic and continued regression after hypophysectomy.

Animals↗
PubMed1984

Chromosome aberrations induced by 7,12-dimethylbenz[a]-anthracene in bone marrow cells of spontaneously hypertensive rats (SHR) and control Wistar Kyoto (WKY) rats: time course and site specificity.

The frequency of chromosome aberrations (CA) induced by iv injection of 7,12-dimethylbenz[a]anthracene [(DMBA) CAS: 57-97-6] was examined with the use of control Wistar Kyoto (WKY) rats and spontaneously hypertensive rats (SHR). SHR appear to be analogous to hypertensive humans, since evidence has been reported of a difference in tumor susceptibility between SHR and WKY strains. Injection of DMBA evoked CA in bone marrow cells of both SHR and WKY rats. The frequency of CA in SHR was significantly higher than in WKY rats at 12 and 18 hours after DMBA treatment. With regard to the relative frequencies of aberrations in SHR and WKY rats, chromosomes 1 and 2 were more susceptible to DMBA-induced CA. The proportion of breaks that occur in the "hot spot" at 6 hours after DMBA treatment was distributed nonrandomly at a site approximately 40% of the total length from the centromere in chromosome 1 and at lengths of approximately 30 and 55% in chromosome 2. The specific distribution of CA seemed to be caused by a cell cycle-specific effect. These results, confirming nonrandom CA induced by DMBA in bone marrow cells of WKY rats, are similar to previous reports in which Long-Evans rats were used. Thus they indicate that a common mode of action by DMBA at the chromosome level in rat bone marrow cells was observed in different strains and that SHR were more sensitive than WKY rats to CA induced by DMBA.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1984

An ultrastructural and histochemical study of alveolar soft part sarcoma with special reference to the nature of crystals.

We have presented a case of typical alveolar soft part sarcoma probably originating from the soft tissues of the retroperitoneum with metastasis to the brain. An ultrastructural study including histochemical observation of the metastatic lesion was performed to clarify the nature of the crystals characteristic to the tumor cells of this disease. The crystalline structures have acid phosphatase activity at a histological and ultrastructural level. Our results suggested that they might be derived from coalescence of primary lysosomes or by digestive disintegration of some protein.

Acid Phosphatase↗
PubMed1984

Supersensitivity of the rabbit iris sphincter muscle induced by trigeminal denervation: the role of substance P.

The rabbit left ophthalmic nerve (first branch of the left trigeminal nerve) was cut at the intracranial, peripheral side of the trigeminal ganglion and the effects of denervation were examined using iris sphincter muscle preparations isolated from the left and right eye, as denervated and control innervated preparations, respectively. Electrical transmural stimulation produced a substance P-operated contraction, in addition to a cholinergic one, in the preparation isolated from the right control eye. The former response was abolished in the preparation isolated from the left denervated eye, thereby indicating that the trigeminal, substance P nerve ipsilaterally innervates the iris sphincter muscle. Exogenously applied carbachol and substance P produced concentration-dependent contractions in preparations isolated from either eye. Supersensitivity characterized by a decrease in median effective concentration (EC50) values and an increase in maximal response was observed in the responses to both agents of the left denervated preparation. Such supersensitivity developed slowly after trigeminal denervation and 3 weeks was required for full development. Exogenously applied KCl produced substance P-operated and direct muscle contractions in the right control preparations. In the left denervated preparations, the substance P-operated contraction was either markedly attenuated or abolished, while the direct muscle-related contraction was enhanced after trigeminal denervation. The length of the left denervated preparation was longer than that of the right control preparation, and the resting tensions required to produce maximal carbachol contraction shifted to lower values. These physical changes of the iris sphincter muscle developed within 5 days after trigeminal denervation. In the non-denervated preparation treated with capsaicin in vitro, electrical transmural stimulation and KCl failed to produce the substance P-related contraction. However, supersensitivity to neither exogenously applied substance P, carbachol and KCl nor physical changes were observed in the capsaicin-treated preparation. These results suggest that trigeminal, substance P-related nerves tonically and ipsilaterally innervate the rabbit iris sphincter muscle and that the denervation results in non-specific supersensitivity. These findings are essentially the same as those observed in various types of smooth muscles after autonomic denervation.

Action Potentials↗
PubMed1984

Induction of hepatic glutathione transferase and suppression of 7,12-dimethylbenz[a]anthracene-induced chromosome aberrations in rat bone marrow cells by Sudan III and related azo dyes.

Noninbred Long-Evans rats fed the reduced form of glutathione (GSH) 2 hours before injection with 7,12-dimethylbenz[a]anthracene [(DMBA) CAS: 57-97-6)] showed a significant suppression of DMBA-induced chromosome aberrations (CA) in bone marrow cells. However, rats given injections of ethyl maleate [(EM) CAS: 141-05-9; (z)-2-butenedioic acid diethyl ester] 0.5 or 2 hours before being killed showed a remarkable fall in the hepatic GSH level. Furthermore, the administration of EM and bromosulfophthalein [CAS: 71-67-0; 3,3'-(4,5,6,7-tetrabromo-3-oxo-1(3H)-isobenzofuranylidene) bis(6-hydroxy)benzenesulfonic acid disodium salt] shortly before the DMBA injection inhibited the suppressive effects of Sudan III on DMBA-induced CA. A clear positive correlation was found between the capacity of Sudan III and related azo dyes to protect against DMBA-induced CA in bone marrow cells and glutathione transferase (GST) activity toward 1-chloro-2,4-dinitrobenzene in the liver cytosol induced by these azo dyes. DMBA activation with hepatic S-9 obtained from rats treated by polychlorinated biphenyls (PCB), phenobarbital, and Sudan III in the Ames system was high in this order as was also the case for the cytochrome P450 content. The addition of GSH to the Ames system containing S-9 from PCB-treated rats resulted in a substantial loss in the mutagenicity of DMBA. The present results suggest that GST and GSH play important roles in DMBA inactivation in rats previously administered Sudan III.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1984

Capsaicin and bradykinin-induced substance P-ergic responses in the iris sphincter muscle of the rabbit.

Exogenously applied capsaicin and bradykinin produced contractile responses in the rabbit iris sphincter muscle and responses were suppressed remarkably by [D-Pro2, D-Trp7,9]-substance P, a substance P antagonist, and disappeared in trigeminally denervated preparations. Thus, the responses to capsaicin or bradykinin were considered to be mediated by substance P released from the trigeminal nerve. Repetitive application of capsaicin or bradykinin produced a gradual decline in the responses, thereby indicating the development of tachyphylaxis. Furthermore, bradykinin failed to induce any response after the development of capsaicin-induced tachyphylaxis, but after the development of tachyphylaxis to bradykinin, responses to capsaicin persisted. Electrical transmural stimulation produced cholinergic and substance P-ergic responses in the rabbit iris sphincter muscle. Substance P-ergic response to electrical transmural stimulation also was abolished after development of tachyphylaxis to capsaicin, but not to bradykinin. The contractile response to exogenously applied substance P was not affected by the development of tachyphylaxis to capsaicin and bradykinin. These results suggest that capsaicin and bradykinin produce substance P-ergic contractile responses mediated by the trigeminal nerve and that the mechanisms of action differ between the two drugs. These effects of capsaicin and bradykinin are discussed in relation to occurrence of neurogenic inflammation in the eye.

Animals↗
PubMed1984

[Macroamylasemia, report of two cases].

Serum amylase isozyme was determined in 2 cases with normal urinary amylase but persistantly high serum amylase. Both cases showed dominant S-type amylase associated with tailing findings that was characteristic of macroamylasemia. Moreover, using the immunofixation method, the serum amylase was found to be bound with IgG (K) in case 1 and with IgA (L) in case 2.

Adult↗
PubMed1984

[Two autopsy cases of intramedullary spinal cord metastasis].

Two autopsy cases of intramedullary metastasis to the spinal cord from small cell lung cancer and seminoma of the testis are reported and a review of the literature is presented. Rather than lung cancer, the most common primary tumor of this rare intramedullary spinal cord metastasis is seminoma of the testis. In our case, we posit the occurrence of hematogenous spread via arterial and vertebral venous system.

Aged↗
PubMed1984

[Mass screening for colorectal cancer by occult blood testing under restricted diet].

We conducted a mass screening survey for colorectal cancer by the combination of fecal occult blood tests under a restricted diet and a medical questionnaire in 7,392 healthy volunteers. Further diagnostic work-up was needed in 1,934 (26.2%) individuals. Of these, 1,409 (72.9%) showed occult blood in at least one slide, 245 (12.7%) had symptoms and 306 (15.8%) had a positive family history. Proctosigmoidoscopy, barium enema and flexible colonoscopy were performed in 1,251, 779 and 95 persons, respectively. Colorectal cancers were detected in 10 individuals (0.14%); 5 of these were in the early stage.

Adult↗
PubMed1983

Enzyme immunoassay of thromboxane B2.

An immunoassay for thromboxane B2 was developed in which the hapten molecule was labeled with beta-galactosidase. The immunoprecipitate formed after competition between enzyme-labeled and unlabeled thromboxane B2 was subjected to a fluorometric assay of beta-galactosidase. Thromboxane B2 was detectable in the range of 0.1-30 pmol. Both enzyme immunoassay and radioimmunoassay showed essentially the same cross-reactivities with other prostaglandins and their metabolites when the same antibody was used. Known amounts of thromboxane B2 were added to human plasma, and the sample was applied to an octadecyl silica column. The extract was analyzed by enzyme immunoassay to examine the correlation between the added (x) and measured (y) thromboxane B2 (y = 1.09x + 11.07 pmol/ml, r = 0.99). A satisfactory correlation was observed between radioimmunoassay (x) and enzyme immunoassay (y) (y = 0.92x + 4.64 pmol/ml, r = 0.96). The validity of enzyme immunoassay was also confirmed by gas chromatography-mass spectrometry of a dimethylisopropylsilyl ether derivative of thromboxane B2 methyl ester. The method was applicable to the assay of thromboxane B2 produced from endogenous precursor during thrombin-induced aggregation of human platelets.

Cross Reactions↗
PubMed1983

Physicochemical studies on leukocyte alkaline phosphatase.

Leukocyte alkaline phosphatase (ALP) was subjected to polyacrylamide gradient gel electrophoresis and its observed characteristic mobility compared with the ALP of placenta, intestine, liver, and bone. Comparison runs showed that leukocyte ALP moved more anodal to the origin than the others. Physicochemical differences between the leukocyte and other ALP were examined, based on studies of inhibition by L-phenylalanine, L-homoarginine, urea and EDTA, and of heat inactivation. Leukocyte ALP was inhibited strongly by L-homoarginine and urea but not by L-phenylalanine, which seemed similar to the effect of inhibition of liver and bone ALP. However, heat inactivation appeared to be helpful in distinguishing leukocyte from liver and bone ALP.

Alkaline Phosphatase↗