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Biomedical subjects

M Ueda

Publications and source records attributed to M Ueda.

At least 901 records · Page 50Linked to original sources
PubMed1992

Histological pancreatitis in end-stage renal disease.

To clarify a possible cause of hyperamylasemia in end-stage renal disease (ESRD), histological studies were performed on the pancreatic glands of twenty-seven autopsied patients with ESRD who had received long-term hemodialysis. The findings were compared with those in a similar number of age-matched control subjects. Histological evidence of pancreatitis was found in 51.9% of the ESRD patients as compared with 14.8% in the controls (p < 0.005). The pancreatitis was chronic in nature in 85.7% of the ESRD patients showing changes of pancreatitis. Secretin administration to an additional group of twelve patients with ESRD induced an elevation in the activities of both total and P-type serum amylase in only one patient. These findings suggest that although histological pancreatic alterations are common in patients with ESRD, they are probably not responsible for the P-type hyperamylasemia frequently found in such patients.

Adult↗
PubMed1992

Mitotic activity of cells in the fibrous zone of the rat mandibular condyle.

To investigate cell renewal in this fibrous zone, Wistar rats at 3 and 6 weeks of age were injected intraperitoneally with colchicine (1 mg/kg) three times, at 10:00, 13:00 and 16:00 h, and mitotic cells were examined after killing the rats at 18:00 h. Colchicine induced a significant increase in the number of arrested metaphases in the fibrous and the proliferating cell zone. The mitotic rates (per 1000 cells per h) in the fibrous zone at 3 weeks of age were 0.426 for the superficial layer and 0.266 for the deeper layer. These findings suggest that the fibrous zone of young rats grew with the proliferation of the cells within this zone. Age-associated histological changes in the fibrous zone were related to changes in mitotic rates within that zone.

Aging↗
PubMed1992

Immunodeficiency and the role of suppressor cells after human bone marrow transplantation.

Although not totally analogous to a fetus or newborn, the donor-derived immune system attempts to recapitulate immune ontogeny over a 1- to 2-year period. Early after BMT, primitive functions such as cytotoxicity are present in an immunologic environment dominated by suppressive signals. The suppressive signals are so intense that helper cells are inhibited in their ability to function. Teleologically, the suppressive signals may be required for the development of specific tolerance. Full immune reconstitution is accompanied by the development of specific suppressor activity and specific immune functions. Cognitive T cell-T cell and T cell-B cell interactions are dependent upon the finely tuned and orchestrated synthesis of lymphokines, as well as the expression of specific receptors for the lymphokines on target cells. Future studies will elucidate the mechanisms involved in such interactions in lymphocytes from BMT recipients. Understanding the mechanisms involved will permit the development of therapeutic strategies to manipulate immune responses after BMT.

Bone Marrow Transplantation↗
PubMed1992

Detailed analysis of an amplified region at chromosome 11q13 in malignant tumors.

We have examined the amplification unit at chromosome band 11q13 in 12 primary tumors and one cancer cell line (A431) with 15 DNA markers. The amplified region and size varied from one tumor to another; the smallest amplicon was estimated to be 700 kb long and the largest was 4.5 Mb long at maximum, on the basis of a physical map. Furthermore, the DNA amplified in tumors was not always continuous, because in three cases one locus within the amplicon was not amplified. The amplified region common to all 13 cancers consisted of 500 kb of DNA which incorporated eight defined loci (BCL-1, cCI11-524, cCI11-283, cCI11-234, HBI-1, cCI11-454, HSTF1, and INT2). As two of them, cCI11-524 and cCI11-454, were found to contain DNA sequences conserved in other species, one or both of these loci might encode the gene(s) that may be associated with progression of these tumors.

Blotting, Southern↗
PubMed1992

Altered distribution of 1-2B7B antigen in basal cell carcinoma, squamous cell carcinoma and Bowen's disease.

Skin lesions of basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and Bowen's disease were immunohistochemically examined using the 1-2B7B monoclonal antibody, which recognizes a 120 kDa polypeptide component found in hemidesmosomes of normal human epidermis and hemidesmosome-like adhesion junction of vascular endothelial cells, to disclose altered characteristics of the interface between the tumor cell aggregate and stromal tissues of the epidermal neoplasms. In BCC, 1-2B7B antigen was rarely expressed at the tumor cell aggregate-stromal tissue interface, where poorly developed hemidesmosometonofibril complexes and a normal-looking lamina densa were detectable. In SCC and Bowen's disease, 1-2B7B antigen was expressed not only along the interface of the tumor nest and stromal tissue, but also in the intercellular space of the desmosomes and other adhesion junction structures that lack associating tonofibrils. In the invading front of SCC, 1-2B7B antigen had partly disappeared from the tumor cell aggregate-stromal tissue interface, where neither hemidesmosomes nor lamina densa were noted. The altered distribution of this hemidesmosomal component in the epidermal neoplasms seems to reflect aberrant interaction of neoplasmic cells and surrounding stromal tissue.

Antibodies, Monoclonal↗
PubMed1992

Simple in vivo bioassay without radioisotopes for recombinant human erythropoietins.

A simple in vivo bioassay suitable for routine testing of quality control of recombinant human erythropoietin (rHuEPO) analogues was developed. The assay took four days, normal mice were used and radioactive compounds were not needed. EPO activity was measured by the increased number of some part of reticulocytes which increased specifically and dose-dependently by the injection of rHuEPO. They were considered to be mostly immature reticulocytes and were counted as the residual particles from blood cells after treatment with a hemolysing reagent. These particles could be counted by conventional automated microcell counters. The assay procedure was simple and easy. The sensitivity, reliability and reproducibility of this method were acceptable for routine in vivo bioassay of rHuEPOs. This method was economical, and can be used instead of the existing bioassays for rHuEPOs.

Animals↗
PubMed1992

In vivo biological activities of recombinant human erythropoietin analogues produced by CHO cells, BHK cells and C127 cells.

The in vivo biological activity of four pharmaceutical preparations of recombinant human erythropoietin was compared. Two of the erythropoietins were produced by Chinese hamster ovary cells, CHO-K1, and the others were produced by mouse mammary cells, C127, and baby hamster kidney cells, BHK-21. The activities of the analogues were estimated by a simple cell counting method with conventional automated microcell counters. The amounts of these analogues gave straight logarithmic dose-response curves when plotted against the count of particles resistant to hemolysing reagent, which particles were mostly immature reticulocytes. The lines from the four analogues were parallel to each other. The relative activities of these analogues were 1.02, 1.19 and 1.21 when one of the analogues was arbitrarily used as the standard. These differences in the extent of the activity were not significant. Thus, the four recombinant human erythropoietin analogues, produced by four different mammalian cell lines, expressed the same biological potencies in vivo corresponding to their units, and the units used up to now by the manufacturers are equivalent. These results also draw the conclusion that the new simple in vivo bioassay can replace the existing accepted assay methods.

Animals↗
PubMed1992

Induction of protective immunity to Brugia pahangi in jirds by drug-abbreviated infection.

Protective immunity of homologous challenge infection was examined in jirds after drug-abbreviated infection with Brugia pahangi. Mebendazole (MBZ) treatment at the early prepatent (5-7 weeks of post infection) or the late prepatent (7-9 weeks of post infection) period was highly effective in causing almost complete eradication of the primary infection. After challenge infection, the worm burden was significantly reduced 19% (31.1 in average) and 77% (9.5) to that of the controls (38.8 and 41.7), respectively. The magnitude of eosinophil response paralleled the degree of protection. No or only a few microfilariae were seen after challenge infection in jirds treated during the prepatent periods. They were also resistant to intravenous challenge with the microfilariae of B. pahangi. MBZ treatment at the patent period was, on the contrary, incomplete against primarily infected adult worms, and was not able to induce either significant protection (30.1 vs 33.1 in control) or eosinophil response to the challenge infection.

Animals↗
PubMed1992

Beta-oxidation of butyrate, the short-chain-length fatty acid, occurs in peroxisomes in the yeast Candida tropicalis.

When an n-alkane-utilizable yeast, Candida tropicalis pK233, was cultivated on butyrate, the fatty acid of shortest chain-length for beta-oxidation, as the sole source of carbon and energy, catalase and the enzymes of the fatty acid beta-oxidation system were inducibly synthesized at high levels. As in the alkane-grown cells, the proliferation of peroxisomes was harmonized with the induction of peroxisomal enzymes. The results of subcellular fractionation and immunoelectronmicroscopy indicated the localization of these enzymes in peroxisomes, not in mitochondria. It was suggested that only peroxisomes have a role in fatty acid beta-oxidation in the yeast cells, unlike in mammalian cells, in which cooperation between peroxisomes and mitochondria is essential.

Acetyl-CoA C-Acyltransferase↗
PubMed1992

Physiological roles of acetoacetyl-CoA thiolase in n-alkane-utilizable yeast, Candida tropicalis: possible contribution to alkane degradation and sterol biosynthesis.

The presence of two types of thiolases, acetoacetyl-CoA thiolase and 3-ketoacyl-CoA thiolase, was demonstrated in peroxisomes of n-alkane-grown Candida tropicalis [Kurihara, T., Ueda, M., & Tanaka, A. (1989) J. Biochem. 106, 474-478], while acetoacetyl-CoA thiolase was also shown to be present in cytosol. The activity of the enzyme in cytosol was constant irrespective of culture conditions, while the peroxisomal enzyme was inducibly synthesized in the alkane-grown yeast cells. These results indicate that peroxisomal acetoacetyl-CoA thiolase participates in alkane degradation, while the cytosolic enzyme is associated with other fundamental metabolic processes, probably sterol biosynthesis, because this enzyme can catalyze the first step of the sterol biosynthesis. 3-Hydroxy-3-methylglutaryl (HMG)-CoA reductase, a key regulatory enzyme of sterol biosynthesis, was found to be localized exclusively in microsomes of the alkane-grown yeast cells. These results suggest that yeast peroxisomes do not contribute to sterol biosynthesis, unlike the case of mammalian cells.

Acetyl-CoA C-Acetyltransferase↗
PubMed1992

Intracellular glutathione and its metabolizing enzyme activities in a metastatic variant melanoma cell line.

Levels of glutathione peroxidase (GSH-PX), glutathione-S-transferase (GST), gamma-glutamyl transpeptidase (gamma GTP) and glutathione reductase (GR) activities in the B16-F10 metastatic melanoma cell line are higher than those in non-metastatic B-16 murine melanoma cells. An inverse relationship was observed between the level of reduced glutathione (GSH) and metastatic capacity. Interferon (IFN), an antitumour and antimetastic agent, reduced the experimental metastatic capacity of B16-F10 cells while increasing the intracellular GSH content. This was associated with a fall in activity of GSH-metabolizing enzymes. These results suggest a correlation of intracellular GSH and its metabolizing enzymes with malignant transformation.

Animals↗
PubMed1992

Lamina densa malformation involved in histogenesis of primary localized cutaneous amyloidosis.

Skin lesions of lichenoid amyloidosis and macular amyloidosis were immunohistochemically investigated using five monoclonal antibodies against basement membrane zone (BMZ) components. A hemidesmosomal component did not contribute to amyloid deposits, but components of the lamina densa and anchoring fibrils were associated with amyloid deposits in the uppermost dermis. Immunoelectron microscopy revealed that these BMZ components were not only aggregated in the BMZ and dermis, but were also involved in the individual amyloid islets. The lamina densa was disrupted in the interface areas just above the amyloid deposits, where cytoplasm of the basal cells directly faced the aggregate of amyloid filaments. Aggregates of some BMZ components were continuous to the amyloid islets from the lamina densa area. These findings suggest that a lamina densa malformation is involved in amyloid production in the interface of the BMZ, and support the secretion theory rather than the fibrillar body theory of amyloidogenesis in these types of primary localized cutaneous amyloidosis.

Amyloid↗
PubMed1992

Assessment of an EIA for measuring human serum erythropoietin as compared with RIA and an in-vitro bioassay.

A recently developed enzyme-linked immunosorbent assay (EIAZ, ELISA) using two murine monoclonal anti-erythropoietin antibodies was compared with a radioimmunoassay (RIA) and a commercial in-vitro bioassay, EPOS, for measuring serum erythropoietin (Epo) in humans. Specificity and validity for Epo-EIA and the other two assays were examined. The serum Epo in normal subjects was 18 +/- 12 mU/ml (mean +/- SD, n = 80) for EIA compared with 22.5 +/- 18.5 mU/ml (n = 20) for RIA and 136 +/- 132 mU/ml (n = 14) for the bioassay. The serum Epo concentrations in normals and patients were highly comparable between EIA and RIA for Epo (P less than 0.01, r = 0.95). Epo concentrations by the EIA for normal female and male subjects were 20.5 +/- 13 and 16.5 +/- 10 mU/ml, respectively. Epo levels in patients with secondary polycythaemia or autoimmune haemolytic anaemia were significantly higher than normal subjects by the three methods. Epo levels in patients with chronic renal failure were within the normal range. By the EPOS bioassay, the Epo concentrations of normals and patients with renal failure were significantly higher than expected (136 +/- 132 and 447 +/- 273, respectively). Due to its inherent design, the EPOS bioassay possibly measures bone marrow proliferative activity in response to other serum growth regulators besides erythropoietin and was found to be unsuitable for clinical assessment of Epo. We concluded that the new EIA and RIA were similarly sensitive, reliable and accurate for measurement of serum Epo. The EIA method has the advantage of being less time consuming, more convenient and avoids the use of a radioisotope.

Adolescent↗
PubMed1992

Spontaneous infarction of an intraductal papilloma of the breast: cytological presentation on fine needle aspiration.

A relatively rare case of spontaneous infarction of an intraductal papilloma of the breast is presented which was considered to be suspicious for malignancy on fine needle aspiration (FNA) cytology. The aspirate revealed several groups of atypical cells featuring a high nuclear-cytoplasmic ratio, coarsely granular chromatin, and somewhat prominent nucleoli. There was abundant necrotic cellular debris in the background. These cellular features were considered evidence of ductal carcinoma of the breast. The correct diagnosis was made by open biopsy which revealed necrosis involving the breast due to infarction of an intraductal papilloma.

Adult↗