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Biomedical subjects

T Matsui

Publications and source records attributed to T Matsui.

At least 901 records · Page 50Linked to original sources
PubMed1986

Production of histological changes mimicking primary biliary cirrhosis in rabbits by immunization with bile duct antigen.

Histopathological liver changes resembling primary biliary cirrhosis were induced in an experimental animal model. A special strain of rabbit received an antigen prepared from scrapings of bovine gallbladder mucosa. Eventually, 47 out of 84 antigen-treated rabbits displayed histopathological liver features resembling those of chronic non-suppurative destructive cholangitis as seen in humans. In addition, granuloma formation, ductular proliferation and fibrosis were seen in some cases. However, advanced lesions consistent with micronodular cirrhosis have not been found. Lymphocytes seemed to play an important role triggering early pathogenetic mechanisms, judging from the presence of lymphocytes invading the basement membrane of the affected bile ducts. Furthermore, we observed by electron microscopy that the epithelial cells of the involved bile ducts revealed both mitochondrial swelling and dilatation of endoplasmic reticulum cisternae. In summary, our experimental animal model offers interesting possibilities regarding the study of pathogenesis and development of primary biliary cirrhosis.

Animals↗
PubMed1986

Inhibitors of IL-2 production and IL-2 receptor expression in human leukemic T-cell line, Jurkat.

1-(5-Isoquinolinylsulfonyl)-2-methylpiperazine (H-7), a protein kinase inhibitor, suppressed interleukin 2 (IL-2) production and IL-2 receptor (IL-2R) expression of the human leukemic T-cell line, Jurkat, induced by 12-O-tetradecanoyl-phorbol-13-acetate and phytohemagglutinin-P. This effect was significant at 5 microM H-7 without loss of cell viability. Such activity was not observed with N-(2-guanidinoethyl)-5-isoquinolinesulfonamide (HA 1004), a potent inhibitor of cGMP- and cAMP-dependent kinases, and a weak inhibitor of Ca2+-phospholipid-dependent protein kinase (protein kinase C). These findings suggest that protein kinase C is more closely associated with IL-2 receptor expression and IL-2 production of T cells than cGMP- or cAMP-dependent kinases. In addition, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7), a calmodulin inhibitor, suppressed both IL-2 production and IL-2R expression. Cycrosporin A (Cy A), a potent immunosuppressive drug, markedly inhibited IL-2 production of Jurkat cells whereas it did not affect the IL-2R expression. Thus, the mechanism of action of Cy A appears to differ from that of the protein kinase inhibitor, H-7, and the calmodulin inhibitor, W-7.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1986

Nude mice bearing human primary hepatocellular carcinoma that produces hepatitis B surface, core, and e antigens, as well as deoxyribonucleic acid polymerase.

A primary hepatocellular carcinoma, from a patient carrying hepatitis B virus, was transplanted to athymic nude mice, and maintained through eight passages involving 39 mice. Hepatitis B surface and e antigens were detected in the circulation of tumor-bearing mice. Hepatitis B surface, core, and e antigens were demonstrated in tumor cells. Hepatitis B core particles were visualized in the tumor extract by immune electron microscopy, and they exhibited an activity of deoxyribonucleic acid polymerase. In the tumor tissue, deoxyribonucleic acid of hepatitis B virus was present both in integrated and extrachromosomal forms. Nude mice carrying the tumor would provide opportunities for studying the replication of hepatitis B virus and the expression of its various proteins, and also for evaluating the efficacy of virustatic drugs in interrupting the persistent infection.

Aged↗
PubMed1986

Faithful initiation of the in vitro transcription of a cloned rDNA from Tetrahymena pyriformis.

A cloned rDNA fragment containing the transcriptional start point of Tetrahymena pyriformis was transcribed in vitro with a crude extract from homologous Tetrahymena cells. When a KpnI-HindIII fragment from the cloned rDNA plasmid was used as the template, the runoff transcription gave rise to two major RNA products about 490 and 460 nucleotides (nt) in length. An RNA of about 490 nt long was found to correspond to the expected transcript starting from the in vivo start point determined at our laboratory [Saiga et al., Nucl. Acids Res. 10 (1982) 4223-4235]. Precise size determination was performed using an RNA size marker prepared by hybridizing the template DNA with in vitro-capped 35S pre-rRNA followed by treatment with single-strand specific P1 nuclease. The size of the runoff transcript changed as predicted, according to downstream truncation points. The effects of alpha-amanitin and actinomycin D showed the transcription to be dependent on the added template DNA and to be catalyzed by form-I RNA polymerase. Possible reasons for the discrepancy between our determination of the size of the transcription product and that of Sutiphong et al. [Biochemistry 23 (1984) 6319-6326] are discussed.

Amanitins↗
PubMed1986

Clinical features of nongangrenous ischemic colitis. A comparison of stricturing and transient forms.

Forty cases of nongangrenous ischemic colitis were studied to find the different clinical features between stricturing form and transient form. Clinical and laboratory findings were compared between two groups, 15 cases of stricturing form and 25 of transient form, which were diagnosed by follow-up barium enema radiography. The following four items, of the nine studied, were significantly different between the two groups; namely, patients of stricturing form were older in age, had longer time intervals from the onset of disease to disappearance of subjective symptoms and to normalization of white blood cell count and/or erythrocyte sedimentation rate, and showed an increase in 1-h erythrocyte sedimentation rate on day 5 or earlier of the disease. Our observations indicate that the age and 1-h erythrocyte sedimentation rate might be useful indicators to differentiate the stricturing and transient forms early after the onset of the disease.

Adult↗
PubMed1986

Integration of region X of hepatitis B virus genome in human primary hepatocellular carcinomas propagated in nude mice.

Tissues of human primary hepatocellular carcinoma (PHC) from six patients infected with hepatitis B virus (HBV) were propagated in nude mice, as well as a strain of hepatitis B surface antigen-positive PHC (PLC/PRF/5). Integration of viral DNA into chromosomal DNA of tumour cells was evaluated by the capacity to hybridize with radiolabelled DNA probes, each representing fundamental parts of the HBV genome, that is S and C genes and regions pre-S and X. All PHC cells possessed region X integrated in their chromosomes. However, integration of the S gene, C gene and region pre-S was found in only six of the seven PHCs. Based on these findings, the integration of region X seems to be most closely associated with carcinogenesis in HBV infection.

Animals↗
PubMed1986

Inhibition of replication and cytopathic effect of human T cell lymphotropic virus type III/lymphadenopathy-associated virus by 3'-azido-3'-deoxythymidine in vitro.

Human T cell lymphotropic virus type III (HTLV-III)/lymphadenopathy-associated virus is the etiologic agent of the acquired immune deficiency syndrome (AIDS) and AIDS-related complex. The effect of 3'-azido-3'-deoxythymidine (AZT) on the HTLV-III/lymphadenopathy-associated virus infection was quantitatively studied with HTLV type I-carrying MT-4 cells. The AZT compound inhibited HTLV-III-induced cytopathic effect and virus-specific antigen expression in MT-4 cells at concentrations of 5 and 10 microM. In addition, a plaque-forming assay was performed to assess the effect of AZT on virus replication in MT-4 cells freshly infected with HTLV-III and in continuous HTLV-III-producing Molt-4/HTLV-III cells. Results showed that AZT efficiently and effectively inhibited the replication of HTLV-III in infected MT-4 cells. AZT is a strong inhibitor of reverse transcriptase activity of HTLV-III as a triphosphate, to such a degree that even 1.0 pM azido-TTP inhibits 50% of reverse transcriptase activity. However, it did not show any effect in the HTLV-III-producing cell line Molt-4/HTLV-III. Thus, AZT has no effect on virus replication of an already integrated virus. When 5 microM AZT was added to HTLV-III-infected MT-4 within 20 h after infection, a striking suppressive effect was noticed. This concentration was much lower than that which inhibits the growth of MT-4 cells. These results confirm those found in a previous report (H. Mitsuya, K. J. Weinhold, P. S. Furman, H. S. Clair, S. N. Lehrman, R. C. Gallo, D. Bolognesi, D. W. Barry, and S. Broder, Proc. Natl. Acad. Sci. USA 82:7096-7100, 1985) and suggest that AZT might be used as an experimental antiviral agent for AIDS and AIDS-related complex.

Antigens, Viral↗
PubMed1986

Adenovirus 2 peptide IX gene is expressed only on replicated DNA molecules.

Transcription of the adenovirus type 2 peptide IX (pIX) gene was examined in transient expression assays. When a nonreplicating plasmid DNA containing the pIX gene was introduced into HeLa cells by the DEAE-dextran method, no pIX gene transcript was detected. In contrast, efficient transcription was observed in the cells transfected with a replicating plasmid containing the pIX gene. Adenovirus early genes did not affect the level of transcription of the pIX gene on either a nonreplicating or a replicating plasmid. Inhibition of plasmid replication with cytosine arabinoside prevented transcription of the pIX gene. By quantitative analysis of the amount of the pIX gene and its transcript in transfected cells, it was concluded that active transcription of the pIX gene occurred only on DNA molecules replicated in the cell.

Adenoviruses, Human↗
PubMed1986

Ischemic colitis: serial changes in double-contrast barium enema examination.

Serial double-contrast barium enema examinations were performed in 40 patients with nongangrenous ischemic colitis, 15 with the stricturing form and 25 with the transient form. Thumb-printing was observed in 30 cases (75%); it appeared within 9 days after the onset of the disease in patients with the stricturing form and within 6 days in those with the transient form. Thumb-printing disappeared about 10 days after the onset, but it lasted considerably longer in two patients with the stricturing form (21 and 29 days, respectively). Longitudinal ulcers were observed in 24 patients (60%), and healing was confirmed on day 20 or later in patients with the stricturing form and on day 9 or later in those with the transient form. Eccentric deformity was found in 19 patients (48%), sacculation in 12 (30%), and transverse ridging in five (13%). These results indicate that longitudinal ulcers and thumb-printing are both characteristic findings of ischemic colitis. The double-contrast study is useful for visualization of the ulcer.

Adult↗
PubMed1986

[New additional operation in the prevention of gastric stasis after selective gastric vagotomy with antrectomy].

The new additional operation for the prevention of the gastric stasis after the selective gastric vagotomy with antrectomy (SV + A) was performed. Our additional operative procedure was followed: After selective gastric vagotomy and antrectomy, gastroduodenostomy was anastomosed at acute angle with the longitudinalis of the stomach. Then, both lesser and greater omentum were incised outside of the gastric vessels. After these procedure, posterior wall sided to lesser curvature was fixed with the edge of the hepatogastric ligament and posterior wall sided to greater curvature was fixed with the retroperitoneum inferior to the pancreas by several sutures. The outcome of these treatments of the additional operation on SV + A enabled to shorten the duration of drainage of gastric juice, as well as smooth intake. By fluoroscopic examination one month after operation, gastric stasis was observed on SV + A due to the contrast medium stored in the ptotic corpus, whereas, in the case of SV + A with our additional operation, smooth gastric emptying was observed without any stasis of the contrast medium, because the corpus was placed upper from the anastomosis portion. In conclusion, our additional operation to SV + A was able to perform easy and safely, and was observed the effective prevention of gastric stasis.

Duodenal Ulcer↗
PubMed1986

Relationships of the molecular structure of aldosterone derivatives with their binding affinity for mineralocorticoid receptor.

The molecular structures of 19-nor-11-deoxycorticosterone (III) and 21-hydroxypregna-4,11-diene-3,20-dione (IV) were determined by X-ray crystallographic analysis and the factors affecting the binding affinities for the mineralocorticoid receptor were examined with six aldosterone derivatives (I-VI) containing these two compounds. The most important factor was found to be the steric one; affinity increased with increasing flatness of the structure. The electronic factor may be a minor influence although a good relationship was found between the affinity and the 13C-NMR chemical shift of the C(5) atom. The factor playing no role in the binding is the hydrophobic one.

Aldosterone↗
PubMed1986

1,25-Dihydroxyvitamin D3-regulated expression of genes involved in human T-lymphocyte proliferation and differentiation.

1,25-Dihydroxyvitamin D3 [1,25-(OH)2D3] inhibited the secretion of gamma-interferon from human T-lymphocytes activated by the calcium ionophore, A23187, or phytohemagglutinin with or without 12-O-tetradecanoylphorbol-13-acetate. The agent also inhibited cell proliferation and interleukin 2 secretion by these cells. The inhibition of gamma-interferon secretion was time and dose dependent and partially abolished by the addition of exogenous human recombinant interleukin 2. To elucidate the molecular events by which 1,25-(OH)2D3 inhibits cell proliferation and lymphokine secretion, complementary DNA probes were used to follow the expression of genes involved in human T-lymphocyte proliferation and differentiation. 1,25-(OH)2D3 inhibited the expression of interleukin 2 and gamma-interferon messenger RNA in human lymphocytes activated by phytohemagglutinin and 12-O-tetradecanoylphorbol-13-acetate. It also inhibited the accumulation of c-myc protooncogene messenger RNA and, to a lesser extent, interleukin 2 receptor messenger RNA in these cells. However, it did not affect the expression of the HLA-DR gene. These results suggest that 1,25-(OH)2D3 selectively regulates T-lymphocyte activation-related genes at the level of messenger RNA.

Calcimycin↗