Search PubMed⌕ Search

Biomedical subjects

N Ohsawa

Publications and source records attributed to N Ohsawa.

At least 127 records · Page 7Linked to original sources

Glucocorticoid receptor in multiple myeloma.

Glucocorticoid receptor levels of myeloma cells were quantitated in 7 patients with multiple myeloma. In 4 patients, glucocorticoid receptor levels were less than 10 fmol/10(6) cells. In 3 patients, receptor levels were from 17.6 to 21.4 fmol/10(6) cells. We further examined the correlation between glucocorticoid receptor levels and effect of dexamethasone on 14C-thymidine incorporation and cell viability using 2 myeloma cell lines, OPM-1 and OPM-2, established from a patient with multiple myeloma. Glucocorticoid receptor levels of OPM-1 and OPM-2 were 8.5 fmol/10(6) cells and 63.2 fmol/10(6) cells, respectively. The sensitivity of OPM-1 to dexamethasone in these studies was lower than that of OPM-2. These results suggest the possibility that the low level of glucocorticoid receptor in myeloma cells may be important for predicting a poor response to glucocorticoid therapy.

Cell Line↗

Purification and characterization of high Ca2+-requiring neutral proteases from porcine and bovine brains.

Porcine and bovine brain high Ca2+-requiring neutral proteases were purified to homogeneity by the same isolation procedures, and their properties were compared. A high degree of similarity existed between the two proteases. The purification procedures included ion-exchange chromatography on DEAE-cellulose, hydrophobic chromatography on phenyl-Sepharose CL-4B, second DEAE-cellulose chromatography, second phenyl-Sepharose CL-4B chromatography, and gel filtration on Ultrogel AcA 34. Both purified enzymes were composed of Mr 75,000 and 29,000 subunits, as shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Both enzymes required 250 microM Ca2+ for half-maximal activity and 700 microM Ca2+ for maximal activity. Sr2+ and Ba2+, but not Mg2+ or Mn2+, also activated both enzymes but not as effectively as Ca2+. Both enzymes displayed maximum activity at pH 7.5-8.0. Leupeptin, antipain, and trans-epoxysuccinyl-L-leucylagmatine inhibited both enzymes. Neurofilament triplet proteins and microtubule-associated proteins were extensively hydrolyzed by both proteases, but tubulin and actin were not hydrolyzed. The amino acid compositions of the two proteases were very similar. Antisera against bovine brain protease cross-reacted with porcine brain protease when examined by immunoelectrotransfer blot techniques.

Amino Acids↗

Lipid metabolism in endotoxic rats: decrease in hepatic triglyceride lipase activity.

Studies were conducted to investigate the effect of E. coli endotoxin administration on hepatic triglyceride lipase (H-TGL) activity in rats, since H-TGL activity is known to behave differently from lipoprotein lipase (LPL) activity in various situations. Plasma triglyceride and free fatty acid concentrations were markedly elevated in animals after injection of endotoxin. Cholesterol and phospholipids were also increased significantly. Lipoprotein analysis by ultracentrifugation showed that the most pronounced increase of lipoproteins was in the VLDL and IDL fractions. Triglyceride lipase activities in post-heparin plasma were markedly decreased. A selective assay for H-TGL activity using a specific antibody revealed that this enzyme as well as LPL is significantly decreased (26% of control) in endotoxic animals. Thus, the increase of VLDL and IDL appears to result from the decrease of both of LPL and H-TGL.

Animals↗

Production of bone-resorbing activity and colony-stimulating activity in vivo and in vitro by a human squamous cell carcinoma associated with hypercalcemia and leukocytosis.

A squamous cell carcinoma of 33-yr-old patient who developed marked leukocytosis and hypercalcemia was transplanted into nude mice in which more marked leukocytosis and hypercalcemia also developed. This tumor (LJC-1-JCK) produced a colony-stimulating factor (CSF) and formed a cyst in the tumor from which a CSF-producing cell line (T3M-1) was established. The CSF causes predominantly formation of granulocytic colonies in addition to macrophage colonies. Bone-resorbing activity (BRA) was detected in the cystic fluid and was eluted as two separate peaks with proteins of an apparent molecular weight of 30,000-50,000 and 10,000-20,000. Colony-stimulating activity (CSA) was eluted at an apparent 30,000 mol wt. The conditioned medium of the T3M-1 cells also contained a BRA with an apparent 14,000 mol wt, whereas CSA eluted at an apparent 30,000 mol wt. PTH, epidermal growth factor, transforming growth factor-alpha, prostaglandin Es, and vitamin D could not account for the powerful BRA. In contrast to CSA, BRA was not inactivated by trypsin and more stable at 70 degrees C. When T3M-1 cells were transplanted into nude mice, marked hypercalcemia developed in addition to granulocytosis. Our findings suggest that the tumor produces and secretes a powerful BRA in vivo and in vitro, which is different from CSA in terms of molecular weight, heat stability, and trypsin treatment. We speculate that the synergistic action of CSF that stimulates macrophage colony formation and recruits osteoclast precursors, and BRA, which stimulates mononuclear phagocytes and/or osteoclasts were responsible for a marked increase in osteoclastic bone resorption and humoral hypercalcemia in the patient.

Animals↗

Effect of phytohemagglutinin on concentrations of glucocorticoid receptors in lymphocytes from patients with connective tissue diseases.

We examined the effect of phytohemagglutinin (PHA) on glucocorticoid receptors in lymphocytes, using peripheral mononuclear leukocytes from patients with connective tissue diseases. Glucocorticoid receptor concentrations and dissociation constants (Kd) for [3H]dexamethasone binding to lymphocytes from patients with rheumatoid arthritis, Sjögren's syndrome, and other connective tissue diseases did not differ significantly from values for normal volunteers. Kd values correlated positively with glucocorticoid receptor concentrations after PHA stimulation both in normal volunteers and in patients with connective tissue diseases. The correlations (r values) for the control group and patients were not significantly different.

Adult↗

The value of urinary polyamine assay in stomach cancer. Comparison with serum carcinoembryonic antigen.

The authors recently established a new simple enzymatic assay method for total urinary polyamines (Cancer Res 1983; 43:2263-2367). In order to assess the clinical usefulness of measuring total urinary polyamines for the detection of cancer, this method has been applied to the assay of polyamines in the urine of 45 patients with stomach cancer who were classified as to clinical stage. In addition, the value of serum carcinoembryonic antigen (CEA) in the same individual patients was measured for comparison. Percentage of patients with elevated levels of total urinary polyamines increased with International Union Against Cancer (UICC) clinical stage, and was 40.0% (6/15), 50% (3/6), 72.7% (8/11), and 84.6% (11/13) for Stage I, II, III and IV stomach cancer patients, respectively. In 32 patients with stomach cancer of potentially operable Stage I, II, and III, elevated levels of total urinary polyamines were found in 17 patients and elevated levels of serum CEA were found in 5 patients. In 13 patients with inoperable stage IV stomach cancer, elevated levels of total urinary polyamines were found in 11 patients and elevated levels of serum CEA were found in 5 patients. Statistical differences in the detection rate were found between the two markers in these two groups of patients. The combination of these two markers did not increase the detection rate of stomach cancer significantly. The data indicate that the determination of total urinary polyamines by the new assay is clinically useful as a potential marker for the detection of advanced stages of stomach cancer and may be more useful than that of serum CEA. Furthermore, this study demonstrates the relationship between urinary polyamine levels and tumor regression and also the prognostic significance of polyamine determination in stomach cancer patients. In 6 of 13 patients who showed elevated levels of urinary polyamines before surgery, polyamine levels fell to within the normal range after successful surgical removal of tumor. In general, each polyamine level decreased significantly following surgery by paired Student's t test analysis. All of the five Stage IV patients with polyamine levels greater than 4.0 mumol/kg/24 hour died in less than 3 months whereas five of eight Stage IV patients with polyamine levels less than or equal to 4.0 mumol/kg/24 hour survived 10 to 20 months. Statistical differences in survival were observed between Stage IV patients with polyamine levels greater than 4.0 mumol/kg/24 hour and those with polyamine levels less than or equal to 4.0 mumol/kg/24 hour.(ABSTRACT TRUNCATED AT 400 WORDS)

Carcinoembryonic Antigen↗

Induction of alkaline phosphatase in neutrophilic granulocytes, a marker of cell maturity, from bone marrow of normal individuals by retinoic acid.

We examined whether chemical agents reported to induce differentiation of leukemic cells also have differentiating effects on normal human granulocytes using alkaline phosphatase activity as a marker. Among 11 compounds examined, only vitamin A analogues were shown to induce this activity in granulocytes from bone marrow of normal individuals. Retinoic acid was the most potent inducer of the activity followed by retinal, whereas retinol and retinol acetate did not induce any activity. The effect on the alkaline phosphatase activity by retinoic acid and retinal was considered to reflect their effect on normal granulocytic differentiation and maturation.

Alkaline Phosphatase↗

Characterization of neutrophil alkaline phosphatase-inducing factor (NAP-IF).

A factor, termed neutrophil alkaline phosphatase-inducing factor (NAP-IF), that has the capacity to increase the NAP activity of granulocytes was characterized by using two samples: cystic fluid (CF) and conditioned medium of a tumor cell line (T3M5). The molecular weight of NAP-IF was shown to be between 13,000 and 45,000, and its isoelectric point was between 5.5 and 6.2. It was sensitive to heat and proteolytic enzymes, but was resistant to DNase and RNase, suggesting that NAP-IF is an acidic protein or glycoprotein. These characteristics of NAP-IF seem to be similar to those of granulocyte-macrophage colony-stimulating factor (GM-CSF) that is also present in the CF. NAP-IF rich fractions obtained by isoelectric focusing from CF were also found to be rich in a subclass of GM-CSF: granulocyte-CSF (G-CSF). Furthermore, a high correlation was noted between the activities of G-CSF and NAP-IF (gamma = 0.798, P less than 0.005). These results suggest that the two activities, i.e., G-CSF and NAP-IF, may be attributable to an identical macromolecule.

Alkaline Phosphatase↗

A kinetic study of [3H]-dexamethasone binding to chick erythrocytes.

The chick erythrocyte has about 300 specific glucocorticoid binding sites per cell. The apparent dissociation constant at 20 degrees C was 0.31 nM after 1 hr incubation and decreased to 0.12 nM after 8 hr incubation. The association rate constant of [3H]-dexamethasone binding to chick erythrocytes was higher than that reported for goat mononuclear leukocytes. The dissociation of [3H]-dexamethasone bound to erythrocytes at 20 degrees C consisted of two components which are similar to the values reported for goat mononuclear leukocytes.

Animals↗

Urinary polyamines as a tumor marker.

We recently established a new simple enzymatic assay method for measuring total urinary polyamines. To evaluate the clinical usefulness of measuring total urinary polyamines as a tumor marker, we have applied this method to the assay of polyamines in the urine of cancer patients. Elevation above 3 SD of the normal mean was found in 116 of the 181 patients with cancer (stomach 49/72 [68.1%], colon 22/32 [68.8%], lung 16/24 [66.7%], blood 15/27 [55.6%], liver 3/14 [21.4%], gallbladder 4/4 [100%], and esophagus 7/8 [87.5%]). Total urinary polyamine levels were determined before and after surgery in 36 patients with gastrointestinal cancer (stomach 22 and colon 14). Urinary polyamine levels fell to within the normal range after successful surgery in 23 of 30 patients who had showed elevated levels of urinary polyamines before surgery. Our data indicate that the determination of total urinary polyamines by our new assay may be useful as a tumor marker.

Humans↗

Purification of a calcium-activated neutral proteinase from human placenta.

A calcium-activated neutral proteinase has been purified to homogeneity from human placenta. The purified enzyme is a dimer composed of Mr 73 000 and 30 000 subunits. Half-maximal activity is observed at 250 microM Ca2+. It requires reduced sulfhydryl groups and neutral pH for optimal activity. Leupeptin, antipain, E-64, sulfhydryl-blocking agents and endogenous proteinase inhibitor inhibit the purified enzyme. This paper is the first to describe the purification and characterization of a calcium-activated neutral proteinase from a human non-muscular parenchymatous organ.

Calcium↗

Establishment of a human colony-stimulating-factor-producing cell line from an undifferentiated large cell carcinoma of the lung.

Two different types of lung cancer, a squamous cell carcinoma designated as OTUK, and an undifferentiated large cell carcinoma named as T3M-10, were investigated in vitro; both produced a moderate neutrophilia in each patient. In order to analyze this phenomenon, primary cultures were performed. Epithelial cells attached and grew in both of the cultures. The conditioned medium from both tumor cells revealed high colony-stimulating-factor (CSF) activities. From T3M-10 tumor cultures, a new CSF-producing cell line has been established. T3M-10 cells have been continuously propagated during the last 28 months and produced CSF. Chromosomal analysis revealed the cell line to be a human aneuploid one with a near-diploid mode. These results indicate that the two different types of lung cancers produce CSF, which may have stimulated granulopoiesis in vivo in the patients as well.

Adult↗

Antibody-dependent cell-mediated cytotoxicity against HLA-A, HLA-B and HLA-DR specificities.

HLA specificity of alloantibodies involved in antibody-dependent cell-mediated cytotoxicity (ADCC) was investigated using PHA-induced lymphoblasts ( PLB ) from peripheral blood and Epstein-Barr virus-induced human lymphoblastoid cell lines (LCL). The ADCC activity with PLB sensitized by HLA-A or HLA-B antibodies was relatively low, but higher than that of control. DR antibodies completely failed to sensitize PLB for ADCC. LCL sensitized by corresponding DR antibodies gave strong ADCC reactions, independent from their D phenotypes. The ADCC reactions against LCL were abolished by absorption of the DR antibodies from the alloantisera. Thus the ADCC with LCL would provide a procedure to study the role of DR antibodies in chronic rejection of long-term renal allografts.

Antibody Specificity↗