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Biomedical subjects

T Koshikawa

Publications and source records attributed to T Koshikawa.

At least 109 records · Page 6Linked to original sources
PubMed1986

Immunochemical similarity of synthetic alpha-(1----3)-branched D-glucans to dextran B1375.

Anti-dextran B1375 antibodies were raised in rabbits by injecting formalin-killed Leuconostoc mesenteroides strain NRRL B1375, and the anti-dextran serum was used to examine native dextran B1375, and synthetic linear and four alpha-(1----3)-branched alpha-(1----6)-D-glucopyranans for similarities. The antiserum reacted with the homologous dextran B1375 and also with all the synthetic linear and branched glucans. Precipitation and precipitation-inhibition studies indicated that the antiserum contained at least three groups of antibodies with different specificities, the first specific for linear alpha-(1----6)-D-glucopyranan structure, the second specific for alpha-D-glycopyranosyl-(1----3)-branching and the last specific for another, unknown structure present in the dextran B1375 molecule. Two samples of the synthetic branched glucans were shown to be immunochemically the most similar to natural dextran B1375 by inhibition experiments.

Antibodies↗
PubMed1986

[Immunohistochemical localization of epithelial membrane antigen, carcinoembryonic antigen and secretory component in urinary bladder cancer].

To clarify the relationship between the immunohistochemical distribution pattern of epithelial antigens in transitional cell carcinomas and their histopathological grading and staging, epithelial membrane antigen (EMA), carcinoembryonic antigen (CEA) and secretory component (SC) were localized. Formalin-fixed paraffin-embedded sections from 55 patients with bladder carcinoma were stained by the indirect immunoperoxidase method. In normal transitional epithelium, EMA was found on the luminal side of the plasma membrane of a few surface layers, and in the cytoplasm of the superficial cells. In the lower grade and stage of transitional cell carcinoma, only the luminal surface of superficial cells was positively stained. Membrane and cytoplasmic staining of EMA was frequently found in the intermediate and basal layers of the carcinoma, and the incidence of cytoplasmic staining increased with the higher grade and stage. CEA was not detected in normal epithelium. Cytoplasmic staining of CEA was progressively more frequent in the higher grade and stage of transitional cell carcinoma. In normal epithelium SC was observed on the apical surface plasma membrane and in the cytoplasm of the superficial cells, as shown in the immunohistochemical staining for EMA. The correlation of immunohistochemical detection of SC with the grade or stage was not as good as the correlations for EMA or CEA. These findings suggest that immunohistochemical examination for EMA, CEA and SC in bladder carcinoma could provide valuable information for grading or staging in pathological diagnosis.

Carcinoembryonic Antigen↗
PubMed1986

Enolase isozymes in renal tubules and renal cell carcinoma.

To elucidate the localization of enolase isozymes in renal tubules and renal cell carcinoma, an immunohistochemical study and quantitative analysis by employing the enzyme immunoassay were performed. The alpha-enolase was localized in almost all epithelial cells of renal tubules except for loops of Henle. The gamma-enolase was localized in macula densa cells and epithelial cells of loops of Henle and collecting ducts of the medulla, but not in those of proximal tubules. In renal cell carcinoma, most tumor cells possessed two enolase isozymes. From these immunohistochemical findings, it is suggested that enolases are present mainly in the alpha alpha form in epithelial cells of proximal tubules, in the gamma gamma form in those of loops of Henle, and in the two forms and/or the alpha gamma form in tumor cells of renal cell carcinoma. The levels of gamma-enolase in the normal cortex were 16.8 +/- 3.7 ng/mg protein (n = 7), whereas those in renal cell carcinoma were 928 +/- 554 ng/mg protein (n = 7), about 55-fold higher than those in the normal cortex. The serum gamma-enolase levels were also enhanced in 20 (49%) of 41 patients with renal cell carcinoma. Because it is generally accepted that renal cell carcinoma is derived from epithelium of proximal tubules, the expression of gamma-enolase has occurred during carcinogenesis.

Carcinoma, Renal Cell↗
PubMed1985

Collapse of cortex expansion during germination of Bacillus megaterium spores.

When spores of Bacillus megaterium ATCC 12872 were incubated with CdCl2, they germinated without decomposition of the cortex. Moreover, the volume ratio of cortex to protoplast-plus-cortex, C/(P+C), of the CdCl2-germinated spores was reduced. Incubation of isolated cortex with the divalent compounds Cd2+, Ca2+, and Mg2+ reduced the gel volume to about 1/5 but incubation with a nonionic compounds, glucose, did not. The spores with reduced C/(P+C) were observed in the early period of glucose-induced germination. The time required for a 50% change in cortex morphology to occur was 2.5 min, which corresponds well with the time for 50% loss of heat resistance. This time was shorter than that necessary for release of peptidoglycan fragments and hydrolysis of cortex glycan chains. These data indicate that cortex hydrolysis is not related to the initiation of germination. 50% of the dipicolinic acid, calcium and magnesium were released at 3.4, 4.0, and 2.4 min, respectively. These results suggest that collapse of cortex expansion by the interaction of cortex with dipicolinic acid and cations released from the core, or exogenous ionic germinants is an important step in the initiation of germination.

Bacillus megaterium↗
PubMed1985

Immunohistochemical localization of gamma-enolase in normal human tissues other than nervous and neuroendocrine tissues.

The neuron-specific enolase, gamma-enolase, is present at high concentrations in tissues of the nervous and neuroendocrine systems and at significant levels in other human tissues as detected by enzyme immunoassay. Its precise localization, however, has remained unclear. We report here the immunohistochemical localization of gamma-enolase in normal adult human tissues other than those of the nervous and neuroendocrine systems using direct and indirect enzyme-labeled antibody methods. The gamma-enolase was found in such smooth muscle cells as the media of aorta, fibromuscular tissue of the prostate, and the myometrium of the uterus, myoepithelial cells, the conducting system of heart, epithelial cells of loops of Henle, and macula densa cells of the kidney. It was also demonstrated in spermatogonia, lymphocytes, plasma cells, platelets, and megakaryocytes and in lesser amounts in bronchial epithelial cells and type II alveolar epithelial cells of the lung, and in secretory cells of the fallopian tube. The significance of its presence in these cells and the application of the gamma-enolase detection for diagnostic purposes in pathology are discussed.

Histocytochemistry↗
PubMed1985

[Effects of phenobarbital on EEG and sensory evoked potentials in normal cat brain].

In adult cats, authors studied changes in parameters obtained by the recordings of sensory evoked potentials following cumulative intravenous administration of phenobarbital. P1 and N1 of cortical SEP showed gradual tendencies to decrease in amplitude and to increase in latency with increasing barbiturate dose. These changes preceded to the appearance of burst-suppression activity on electroencephalogram. At this point I-II and III-IV interpeak latencies of BAEP showed statistically significant increase. BAEP and all early components of SEP (I.II.III) persisted in the extremely high serum concentration of phenobarbital. Furthermore, II-III interpeak latency of BAEP showed no statistically significant increase. These experimental results suggest that sensory evoked potentials will provide useful information in the assessment of the brainstem function in patients under deep coma.

Animals↗
PubMed1985

[A case of renal oncocytoma].

A case of renal oncocytoma is reported. A 56-year-old woman was admitted with the complaint of an abdominal mass. Right transabdominal nephrectomy was performed on January 23, 1984. The resected kidney weighed 262 g and contained a well-demarcated 5 X 5 X 4 cm tumor in the middle portion. The cross section of the tumor was tan-brown. Light microscopic examination disclosed that the greater part of the tumor was composed of cells with abundant, and finely granular eosinophilic cytoplasm and with moderate nuclear pleomorphism. Electron microscopic examination confirmed that the cytoplasm had numerous mitochondria and few other organelles. According to these findings, the tumor was diagnosed as renal oncocytoma. Furthermore, it is noteworthy that in this case there were tubular arrangement of the cells resembling proximal renal tubules in a focal area and a group of cells with considerable nuclear atypia and hyperchromatism in another area. The patient has been well without any local recurrence or distant metastasis ten months after the operation. In addition, fourteen cases of renal oncocytoma in Japan, including the present case, are reviewed.

Adenoma↗
PubMed1984

Cellular and humoral dynamics in the periarterial lymphatic sheaths of rat spleens.

Humoral and cellular dynamics in the periarterial lymphatic sheath (PALS) of the splenic white pulp were investigated in regards to the lymph flow and the architecture of the deep lymphatics in rat spleens. The effects of the splenic venous pressure on the lymph flow were also examined. We found a remarkable depletion of lymphocytes in the PALS and strong lymph flow to the deep lymphatics from the red pulp when the spleen was perfused via the splenic artery at a high speed with a high venous pressure. It was evident that lymphocyte depletion in the PALS depended on the venous pressure during the perfusion. Hemorrhage and lymphocyte depletion in the PALS also occurred after the ligature of the splenic vein. The migration of charcoal particles into the PALS via the red pulp was observed after intravenous or direct injection of charcoal particles. However, the bridging channels in the marginal zone (MZ) were always free of charcoal particles. The existence of deep lymphatics was confirmed around the central arteries which were more than 20 microns in diameter. The ligature of the thoracic duct resulted in the dilatation of the deep lymphatics and intercellular spaces which were easily recognized as the termination of the splenic lymphatics. The terminal lymphatics were localized only in the PALS but not in the follicles. Therefore, the PALS might be considered to act as a central station of the extra-vascular pathway which is connected to both the deep lymphatics and the MZ bridging channels.

Animals↗
PubMed1984

Resistance, germination, and permeability correlates of Bacillus megaterium spores successively divested of integument layers.

A variant strain that produced spores lacking exosporium was isolated from a culture of Bacillus megaterium QM-B1551. Two additional spore morphotypes were obtained from the parent and variant strains by chemical removal of the complex of coat and outer membrane. Among the four morphotype spores, heat resistance did not correlate with total water content, wet density, refractive index, or dipicolinate or cation content, but did correlate with the volume ratio of protoplast to protoplast plus cortex. The divestment of integument layers exterior to the cortex had little influence on heat resistance. Moreover, the divestment did not change the response of either the parent or the variant spores to various germination-initiating agents, except for making the spores susceptible to germination by lysozyme. The primary permeability barrier to glucose for the intact parent and variant spores was found to be the outer membrane, whereas the barrier for the divested spores was the inner membrane.

Bacillus megaterium↗
PubMed1983

[Histological study of urinary bladder tumor: DNA of rat urinary bladder tumor caused by N-butyl-N-(4-hydroxybutyl) nitrosamine and that of human bladder tumor].

Male Fisher rats were treated with 0.5% BBN, and the appearance of cancer in the rat's bladder was observed successively. The quantities of DNA in the normal and tumorous tissues were compared with those in the bladder cancer excised from man; and, the bladder cancer produced in the rat and that occurring in man were compared. 96 rats were divided into 4 groups, and given 8, 16, 24 or 32 weeks of treatment with BBN. Papillomas appeared after administration for 8 weeks, and with subsequent increase in the period of administration the rate of canceration increased. The cancerous tissue proliferated papillarily , the malignancy was grade 1 to 2, no case showed infiltration into the muscle layer, and the quantity of DNA scarcely changed with time, always showing a peak near 2c. In the papillary type of bladder cancer in man, the quantity of DNA showed little change at any stage, and little tendency of infiltration; and, the growth pattern was similar to that of the BBN-induced cancer in rats. On the other hand, non-papillary cancer in man showed a flat histogram of DNA, had a strong tendency of infiltration, and showed a growth pattern different from that of the BBN-induced cancer in rats, thus the BBN-induced cancer in the rat cannot be used as a model of non-papillary infiltrative cancer.

Animals↗
PubMed1982

Wet and dry bacterial spore densities determined by buoyant sedimentation.

The wet densities of various types of dormant bacterial spores and reference particles were determined by centrifugal buoyant sedimentation in density gradient solutions of three commercial media of high chemical density. With Metrizamide or Renografin, the wet density values for the spores and permeable Sephadex beads were higher than those obtained by a reference direct mass method, and some spore populations were separated into several density bands. With Percoll, all of the wet density values were about the same as those obtained by the direct mass method, and only single density bands resulted. The differences were due to the partial permeation of Metrizamide and Renografin, but not Percoll, into the spores and the permeable Sephadex beads. Consequently, the wet density of the entire spore was accurately represented only by the values obtained with the Percoll gradient and the direct mass method. The dry densities of the spores and particles were determined by gravity buoyant sedimentation in a gradient of two organic solvents, one of high and the other of low chemical density. All of the dry density values obtained by this method were about the same as those obtained by the direct mass method.

Bacillus cereus↗
PubMed1982

Identification of taurine occurring sporulating cells of Bacillus subtilis.

An unidentified ninhydrin-positive substance was detected in trichloroacetic acid extract from the sporulating cells of Bacillus subtilis NRRL B558. The substance was isolated as the corresponding 2,4-dinitrophenyl (DNP) derivative, the structure of which was identified with a pyridinium salt of DNP-taurine, based on spectral and synthetic evidence. a pyridine molecule should be introduced into a taurine molecule during the isolation procedure and hence, the original amino acid was assigned to taurine. Taurine was accumulated into the cells from the medium during the early stages os sporulation, and thereafter metabolized or excreted.

Bacillus subtilis↗
PubMed1982

[Parenteral administration of diphenylhydantoin in the pre- and post-operative course on plasma level measurement].

In the neurosurgical care, postoperative convulsion, the especially in the early postoperative course, is one of major complications because it can spoil an otherwise good surgical result. The present study was intended to investigate the prophylactic use of anticonvulsants on chemical measurement of their plasma levels. Parenteral diphenylhydantoin (DPH) given just before craniotomy failed to maintain high level of DPH in the postoperative course even with pretreatment of oral DPH. On the other hand, preoperative oral phenobarbital administration maintained fairly high level in spite of no prescription on the operative day. Intravenous DPH of 250 mg immediately after craniotomy resulted in fairly high level of DPH throughout the early postoperative course in cases of pretreatment of oral DPH. In reviewing the pharmacokinetics of anticonvulsants, the prophylactic use of anticonvulsants in the early postoperative course was discussed.

Adult↗
PubMed1981

Studies on protease from marine bacteria. 1 Isolation of marine Pseudomonas sp 145-2 and purification of protease.

Marine Pseudomonas strain 145-2 having the ability to produce extracellular protease was isolated from Uwa sea water, Ehime prefecture in Japan. This strain grows at 0 degrees - 37 degrees C, but protease production was observed only during 6-10 h cultivation at 20 degrees - 30 degrees C, when casein, as the nitrogen and carbon source in a concentration of 0.5-1.0%, was used. Maximum production of protease by the strain was also observed. Na, K, Ca and Mg ions were needed for growth and production of protease. Two extracellular proteases (proteases I and II) were purified from the culture supernatant by ammonium sulphate fractionation following Sephadex gel chromatography. Protease I had a larger molecular weight than protease II. After purification, proteases I and II were revealed as homogeneous by acrylamide gel electrophoresis and immunoelectrophoresis.

Amino Acids↗