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Biomedical subjects

S Oh

Publications and source records attributed to S Oh.

At least 163 records · Page 9Linked to original sources
PubMed1989

The structure of avian type XII collagen. Alpha 1 (XII) chains contain 190-kDa non-triple helical amino-terminal domains and form homotrimeric molecules.

The monoclonal antibody 75d7, specific for type XII collagen (Sugrue, S.P., Gordon, M.K., Seyer, J., Dublet, B., van der Rest, M., and Olsen, B. R. (1989) J. Cell Biol., in press), was used to characterize the intact form of type XII collagen from chick embryo leg tendons. On an immunoblot of a 6% polyacrylamide gel of tendon extracts, one sharp band is recognized by the antibody at Mr = 220,000, while two fuzzy and poorly resolved bands are seen at Mr = 270,000 and Mr = 290,000. By immunoprecipitation of radiolabeled tendon culture media and electrophoresis of the precipitated material, bands with the same mobilities are observed, indicating that type XII collagen is not proteolytically processed in the extracellular space. Type XII collagen was extracted from tendons with 1 M NaCl in a Tris-HCl buffer and partially purified by concanavalin A-Sepharose and gel permeation chromatographies, using dot immunoblots to monitor the purification. Fractions highly enriched in bacterial collagenase-sensitive proteins with the same electrophoretic properties as type XII collagen were obtained. These fractions did not stain with Alcian blue and neither they nor the immunostained type XII collagen were affected by chondroitinase ABC digestion, indicating that type XII collagen is not a proteoglycan. A disulfide-bonded trimeric CNBr peptide was isolated by affinity chromatography on an antibody column and further purified by gel electrophoresis. Its NH2-terminal amino acid sequence was shown to be unique, demonstrating that type XII collagen is a homotrimer [alpha 1 (XII)]3. After bacterial collagenase digestion, both the immunopurified radiolabeled preparation and the purified tendon extract fraction showed by gel electrophoresis the presence of a large disulfide-bonded, 3 x 190-kDa, collagenase-resistant domain. Rotary shadowing and electron microscopy of the purified type XII fraction demonstrated that the molecule has the structure of a cross consisting of a 75 nm collagenase-sensitive tail, a central globule, and three 60 nm arms each ending in a small globule. After heat denaturation and renaturation, only a very large globule can be seen, attached to the triple helical tail. These results show that type XII collagen has a unique structure and is different from the other matrix constituents described so far.

Amino Acid Sequence↗
PubMed1989

[A case of pulmonary carcinoma presenting flow cytometrical heterogeneity of the nuclear DNA content between its primary focus and the metastatic foci].

We have experienced case involving a 63-year-old patient with a pulmonary carcinoma, who was given an enterectomy following a lobectomy, due to minimal intestinal metastasis. In this case, using flow cytometry, the cancer cell nuclear DNA content was analyzed for the primary tumor focus, the mediastinal lymph node metastatic focus, and the small intestinal metastatic focus. For the primary focus, a cancer cellular population of polyploidy with 2 ploidies of DNA content was observed, while for both the metastatic foci, only a single cancer cellular population was observed, indicating the heterogeneity of the nuclear DNA content between the primary focus and metastatic foci. These 2 metastatic foci had DNA contents completely corresponding to that for a ploidy with a high DNA content in the primary focus, suggesting a metastasis of only the above population from the primary focus. The present case apparently formed metastatic foci in other organs than the lungs but only by cancer cells more susceptible to metastasis among the cancer cells found in the primary focus.

Aneuploidy↗
PubMed1989

[Changes of protein and RNA content in accumulated G1 cells by delta12-PGJ2].

Protein and RNA content in accumulated G1 cells was measured with B16 melanoma cells by flow cytometer to study the mechanism of antineoplastic action of delta 12PGJ2. DNA histogram showed that, after a 6 hr exposure to delta 12PGJ2, the percentage of tumor cells in G2M phase increased, and G1 accumulation with depletion of cell population in S phase was seen after 12-24 hr exposure to 2.0 micrograms/ml of delta 12 PGJ2. Protein content in accumulated G1 cells increased at 6 hr after exposure, and subsequently decreased. However, the protein content treated with delta 12PGJ2 was higher than that of the control. A reduction of RNA content in G1 cells was seen after delta 12PGJ2 exposure. As the result, it was found that delta 12PGJ2 made cell progression ceased in G1 phase of cell cycle, and where protein and RNA content was higher than that of control. It is suggested that some hyper-metabolite state was caused by delta 12 PGJ2 in cultured B16 melanoma cells.

Antineoplastic Agents↗
PubMed1988

[Changes in cell cycle and RNA content in cultured cancer cells treated with cis-diamminedichloroplatinum (II)].

Recent reports have shown that CDDP interacts with RNA and protein as well as DNA. We studied the alteration of cell cycle, cellular RNA content and the effect of nucleic acid metabolism on cultured cancer cells after treatment with CDDP by flow cytometry and 3H incorporation assay. The alteration of cell cycle was found to be accumulation of cells in after delay S phase in cytostatic concentrations, CDDP inhibited 3H-TdR uptake markedly at this time and 3H-UR uptake earlier. Increase in RNA content accompanied accumulation of cells in G2M phase. This increase was not a specific phenomenon caused by CDDP, because increase in RNA content was also induced by other inhibitors of DNA synthesis. It is more likely that the direct alteration of cell cycle and cellular RNA content due to action of DNA-combined CDDP rather than that of RNA-combined CDDP.

Cell Cycle↗
PubMed1988

Modulation of type III collagen synthesis in bovine corneal endothelial cells.

Bovine corneal endothelial cells in culture synthesize predominantly type III collagen, unlike rabbit corneal endothelial cultures which synthesize type IV collagen. In an attempt to document whether this type III collagen synthesis by bovine cells is a tissue culture-specific phenomenon, collagens synthesized by organ culture of bovine Descemet's membrane/corneal endothelium complex were compared with those of subsequent tissue culture cells, up to the eighth passage. The biosynthetically labeled collagens were analyzed on SDS electrophoresis. The soluble fractions of tissues extracted with neutral salt followed by pepsin digestion contained only type I collagen; no other radiolabeled collagens were detected in organ culture. When pepsin treatment was eliminated, type IV collagen was identified in the tissue extract by immunoblot analysis using monoclonal antibody; type III collagen failed to show a positive band by immunoblot analysis. The pepsin-treated medium fraction of the primary culture contained types I, III and V collagen; type IV collagen was identified by either the characteristic electrophoretic mobility or by immunoblot analysis only prior to the proteolysis step. The subsequent subcultures continued to synthesize types I, III and V collagen, but type IV collagen was no longer detectable from the third passage on. No substantial quantitative changes in the expression of individual collagens were observed during subculture. From the primary culture, type I collagen accounted for 30%, type III for 60% and type V for 10%. Enhanced expression of type III collagen was observed in the eighth passage and in primary cultures grown on type I collagen matrix.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

[Surgical treatment of lung cancer for both preserving lung function and maintaining radicality--bronchoplastic surgery].

Fifty cases with lung cancer given bronchoplastic surgery were discussed. Five-year survival rates of all of the cases, those with squamous cell carcinoma, pathological stage I + II cases and absolute curative cases were 36%, 42%, 46% and 59%, respectively, excluding operation death and hospital death. These results were virtually comparable with those of all of the cases with lung cancer which were ever resected in our hospital. The prognosis for cases with adenocarcinoma and of cases operated with bronchoplasty was poor because of direct bronchial invasion from inter-lobar lymph-node metastasis. Hence, this procedure could be better indicated for cases with squamous cell carcinoma, direct primary tumor invasion of the bronchus, and these in which absolute curative operation could be expected clinically. As is characteristic, suture failure occurred in 3 cases, and 2 of them which were followed by pulmonary arterial fistula died of massive bleeding. Preoperative BAI (Bronchial Arterial Infusion had been performed in all 3 cases. It is suggested that there may will be some relation between BAI and suture failure. From the viewpoint of technique, both blood supply preserving and tension relaxing procedures are the most important to avoid suture failure.

Adenocarcinoma↗
PubMed1987

Allergic bronchopulmonary candidiasis: case report and suggested diagnostic criteria.

A patient with an illness consistent with allergic bronchopulmonary candidiasis is described. The patient had asthma, atelectatic pulmonary infiltrates on three occasions, immediate cutaneous reactivity as low as 10(-7) (wt/vol) to Candida albicans extract, and precipitating antibody to this organism. C. albicans was the only organism cultured from two bronchial lavage specimens. Total serum IgE was elevated to 5745 ng/ml and decreased rapidly with corticosteroid therapy. Serologic studies were not consistent with allergic bronchopulmonary aspergillosis. Serum IgE to C. albicans, measured by ELISA after adsorption of IgG from the serum samples by incubation with staphylococcal protein A, was found to be 575% to 650% above control values. The serum IgE antibody activity against Candida decreased with clinical improvement after corticosteroid therapy.

Adolescent↗
PubMed1987

[The influence of smoking on the development of various subtypes of pulmonary carcinoma].

The influence of smoking on the development of pulmonary carcinoma of various histological subtypes was analyzed in 244 primary and 84 metastatic lung cancer patients. The new WHO classification was used for histological diagnosis. The relative risk was calculated by the odds ratio. It was found that all the squamous, small-and large-cell carcinomas were derived from smokers with relative risks of 27.8, 7.5 and 5.6, respectively. On the other hand, adenocarcinoma had very little, if any, relationship with smoking, the relative risk being 1.5 in men and 1.3 in women. The high-risk group for squamous cell carcinoma in men was defined with a regression line of y (duration of smoking) on x (number of cigarettes per day) as y = -0.24 x + 48.6.

Adenocarcinoma↗