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Biomedical subjects

J Nakashima

Publications and source records attributed to J Nakashima.

68 records · Page 4Linked to original sources
PubMed1992

[Studies on the production of endogenous cytokines in patients with renal cell carcinoma].

This study was undertaken to determine the production of tumor necrosis factor (TNF) and interferon-gamma (IFN-gamma) by biological response modifier (BRM) in patients with renal cell carcinoma (RCC). Peripheral blood mononuclear cells (PBMC), which were donated from thirteen patients with RCC and five healthy controls, were cultured with streptococcal preparation, OK432, and/or macrophage-colony stimulating factor (M-CSF), and the TNF levels and IFN-gamma levels in the supernatant were evaluated. TNF activities were assayed by cytotoxicity to L929 cells and IFN-gamma activities were measured by inhibition of the cytopathic effects of sindbis virus on FL cells. The highest levels of TNF in the supernatant were 235.4 +/- 96.0 U/ml/1 x 10(4) cells in patients with renal cell carcinoma and 251.6 +/- 71.8 U/ml/1 x 10(4) cells in healthy controls, which were noted at 12 hours of incubation with the concentration of OK432 adjusted to 0.05 KE/ml. There was no statistically significant difference between the TNF activities induced by in vitro culture of PBMC obtained from patients with renal cell carcinoma and those from healthy controls. The production of TNF by in vitro culture of PBMC with OK432 of 0.05 KE/ml was augmented by adding 100 U/ml M-CSF especially at 48 and 72 hours of incubation, whereas M-CSF alone did not stimulated TNF production. The medium levels of IFN-gamma in six different cultures of PBMC with 0.05 KE/ml OK432 at 12, 24 and 48 hours of incubation were 1.15 +/- 0.34 U/ml/l x 10(4) cells, 2.23 +/- 0.93 U/ml/l x 10(4) cells, and 7.83 +/- 4.00 U/ml/l x 10(4) cells, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Characterization of erythropoietin production in a hepatocellular carcinoma cell line.

This study reports the effects of cyclic adenosine 3'-5' monophosphate (cAMP) and hypoxia on erythropoietin biosynthesis in an erythropoietin-producing hepatocellular carcinoma cell line (Hep3B). Erythropoietin levels in the medium and cell extracts of low-density Hep3B cells after 20-hour incubation under hypoxic conditions (1% O2) were 25.33 +/- 1.50 mU/ml/10(7) cells and 3.60 +/- 0.50 mU/10(7) cells, respectively. These levels were significantly higher than in the respective normoxic controls (medium, 2.51 +/- 0.31 mU/ml/10(7) cells; cell extracts, undetectable [less than 0.31 mU/10(7) cells]). Cobalt also produced a significant increase in medium and cell erythropoietin levels. However, hypoxia and cobalt alone failed to produce an increase in cAMP accumulation in the cell cultures. Erythropoietin levels in the medium and cell extracts from cells exposed to 8-bromo cAMP (1 x 10(-4) mol/L) and forskolin (4 x 10(-6) mol/L) in a hypoxic atmosphere were significantly (p less than 0.05) higher than in the respective hypoxic controls. In addition, forskolin produced a significant (p less than 0.05) increase in cAMP accumulation (180 +/- 11.5 pmol/10(6) cells) under hypoxic conditions compared with the hypoxic controls (cAMP, 2.27 +/- 0.33 pmol/10(6) cells). These results suggest that cAMP elevation is not required in vitro in Hep3B cells for the increase in medium and cell levels of erythropoietin after hypoxia, but may be involved indirectly in erythropoietin biosynthesis, secretion, or both in vivo through some synergistic action with hypoxia.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1991

Increased erythropoietin secretion in human hepatoma cells by N6-cyclohexyladenosine.

The present studies were undertaken to assess the direct effects of N6-cyclohexyladenosine (CHA), a stable adenosine analogue, on erythropoietin (Ep) secretion in hepatocellular carcinoma cells (Hep 3B). Ep levels in the medium of low density Hep 3B cells treated with CHA in concentrations of 10(-5) and 5 x 10(-5) M for 20 h under hypoxic conditions (1% O2) were significantly higher than that of hypoxic controls. In addition, CHA at the same concentrations produced significant increases in adenosine 3',5'-cyclic monophosphate (cAMP) levels in Hep 3B cells after 1-h incubation under hypoxic conditions when compared with hypoxic controls. Dibutyryl cAMP (10(-5), 10(-4) M) also caused significant increases in Ep secretion when compared with control hypoxic cells. On the other hand, 8-phenyltheophylline, an adenosine receptor antagonist, significantly inhibited the stimulatory effects of CHA on both Ep secretion and cAMP accumulation in the Hep 3B cell cultures in response to hypoxia. These data suggest that Ep secretion may be regulated by adenosine receptor-coupled activation of adenylyl cyclase and the generation of cAMP.

Adenosine↗
PubMed1990

Increased secretion of erythropoietin in human renal carcinoma cells in response to atrial natriuretic factor.

The present studies were undertaken to assess the effects of atrial natriuretic factor (ANF) on erythropoietin (Ep) secretion in Ep-producing renal carcinoma (RC) cells using a sensitive radioimmunoassay for Ep. Human ANF produced a significant dose-related increase in Ep secretion at concentrations of 10(-7) and 10(-6) M when compared with vehicle controls. ANF (greater than or equal to 10(-9) M) also significantly increased the intracellular guanosine 3',5'-cyclic monophosphate (cGMP) concentration after 5-min incubation with the RC cells. Scatchard analysis of the human 125I-labeled ANF binding data indicated that the RC cells contain a single class of binding sites with a dissociation constant (Kd) of 93 +/- 1 pM and a binding capacity of 2,190 +/- 750 sites/cell. Incubation of the RC cells with 8-bromo-cGMP in concentrations of 10(-7)-10(-5) M also produced a significant dose-related enhancement of Ep secretion. These findings suggest that the increase in Ep secretion in response to ANF can be attributed, at least in part, to activation of guanylate cyclase, which is coupled to specific ANF receptors on the RC cell.

Atrial Natriuretic Factor↗
PubMed1989

A new approach to characterize whole-gut transit in infants with use of a nonabsorbable intestinal marker.

To characterize mouth to anus transit of intestinal contents, polyethylene glycol (PEG) was given as an intestinal marker to 11 healthy infants, and daily fecal collections were analyzed for PEG concentration per unit of dry stool weight for 9-15 d. Fecal PEG excretion followed first-order kinetics. Thus, half-life (t1/2) and volume of distribution (Vd) of PEG in the gut could be computed for each of seven infants who received continuous daily PEG doses and t1/2 only for four infants who received a single PEG dose. t1/2 of PEG in the gut was 0.99 +/- 0.48 d (means +/- SD). Vd for PEG in the gut was 18.74 +/- 15.38 g of fecal dry weight. We propose that whole-gut transit be expressed in terms of t1/2 and Vd of intestinal contents because these may better characterize the changes in intestinal transit that occur with disease or dietary modifications.

Feces↗
PubMed1989

Enhanced erythropoietin secretion in hepatoblastoma cells in response to hypoxia.

Erythropoietin (Ep) levels in spent culture media of a Hep G2 human hepatoblastoma cell line were measured by radioimmunoassay (RIA), fetal mouse liver erythroid colony formation (FMLC), and the exhypoxic polycythemic mouse assay (EHPCMA). The Hep G2 cells at high density produced approximately 700 mU/ml Ep when measured with the RIA. On the other hand, the Ep levels when assayed in EHPCMA and FMLC were 50 and 2,600 mU/ml, respectively. The bioactivity in FMLC was completely neutralized by an antibody to purified human recombinant Ep, indicating that the erythropoietic activity in the Hep G2 spent culture medium was immunologically equivalent to Ep. Ep levels in the medium from low-density Hep G2 cells in 5% O2 and 1% O2 were 2.5- and 4-fold greater, respectively, than that of 20% O2. In contrast, hyperoxia (40% O2) significantly inhibited Ep production. A significant increase in Ep secretion was also observed when the cells were incubated with cobaltous chloride (2 X 10(-6) -2.5 X 10(-4) M). Tunicamycin (0.5 micrograms/ml), which inhibits N-linked glycosylation, significantly reduced the enhancement of Ep secretion induced by hypoxia (1% O2) without affecting cell growth. Forskolin and cholera toxin, each of which increased the levels of cyclic AMP in the Hep G2 cells by 40-fold, produced a significant (P less than 0.05) further increase in Ep secretion in the presence of hypoxia.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

[Clinical studies of gamma-seminoprotein in prostatic disease. I. Clinical evaluation of serum gamma-seminoprotein].

Serum gamma-seminoprotein (gamma-Sm) in patients with prostatic disease was determined by enzyme immunoassay. A total of 136 patients including 13 untreated and 40 treated patients with prostatic cancer, 45 patients with benign prostatic hyperplasia (BPH) and 38 patients with other urological diseases were analyzed. The mean +/- SD of serum gamma-Sm in the 13 patients with untreated prostatic cancer and the 45 patients with BPH was 31.7 +/- 46.1 and 3.7 +/- 6.6 ng/ml, respectively, there being a statistically significant difference between the two groups. All patients with untreated stage A or B prostatic cancer had a serum gamma-Sm of less than 4 ng/ml (cut off value). The mean level of serum gamma-Sm was 5.1 +/- 1.9 ng/ml for all patients with untreated stage C prostatic cancer; 66% of them had a value above the cut off value. However, it was 55.9 +/- 52.6 ng/ml in all patients with untreated stage D prostatic cancer; 87.5% of them had a value above the cut-off value. These results suggest that gamma-Sm may be a useful tumor marker in the management of patients with prostatic cancer.

Acid Phosphatase↗
PubMed1987

[Clinical studies of gamma-seminoprotein in prostatic disease. II. Immunohistochemical study of gamma-seminoprotein].

Localization of gamma-seminoprotein (gamma-Sm) was examined using horseradish peroxidase-labeled anti-gamma-Sm antibody (Chugai Corp. Ltd., Tokyo, Japan) by the enzyme-labeled antibody method in paraffin embedded specimens of 18 benign prostatic hyperplasias and 32 untreated prostatic cancers. The level of serum gamma-Sm was also determined by enzyme immunoassay in 10 untreated patients with prostatic cancer and 18 with benign prostatic hyperplasia. Specific gamma-Sm staining was detected in prostatic glandular epithelial cells and prostatic secretion of all specimens of benign prostatic hyperplasias and a half of the specimens of prostatic cancers. Specific gamma-Sm staining was shown to correlate with histological differentiation of the prostatic cancer, but no correlation was found between specific gamma-Sm staining and the level of serum gamma-Sm.

Adenocarcinoma↗
PubMed1987

[Bed-side management of post-operative bleeding in transurethral resection of the prostate--hemostatic trial with thrombin solution injected into the resected cavity of the prostate].

To control post-operative bleeding from the resected cavity in transurethral resection of the prostate (TUR-P), 20,000 units of thrombin dissolved in 5-20 ml of physiological saline was injected into the cavity in one shot with a new type of 3-way Foley catheter. The catheter has two holes close to the balloon, and the holes provide outlets through which the solution is directly injected into the cavity. Out of 23 patients between 58 and 87 years old, 11 were given thrombin and 12 were control cases. In each case, urine blood volume (ml/hr) was determined before (a) and after (b) injection. The hemostatic effect was assessed with a "hemostatic index" of b/a. There was a statistically significant difference in the hemostatic indices between thrombin group and the control. (p less than 0.02) This new hemostatic method proved to be a very useful easy bed-side technique to control bleeding even in sudden bleeding after TUR-P. No serious side effects were found during the course of this study.

Aged↗
PubMed1976

Metabolic and hormonal responses to a protein-glucose meal in normal infants and in marasmus and marasmic kwashiorkor.

Blood sugar and plasma free fatty acids (FFA), immunoreactive insulin (IRI), and growth hormone (GH) responses to a protein-glucose meal were determined in normal infants and those with marasmus and marasmic kwashiorkor. Among the normal subjects, fasting blood sugar (BS), peak BS and IRI, and the IRI/BS ratio tended to decrease as age increased. Peak IRI was at least 13muU/ml above fasting in 21 of 24 infants. Fasting GH levels were high 38.5 +/- 13.6 (SD) and 26.3 +/- 14.0 ng/ml, in the two youngest groups (under 1 year) and were comparable with those of the late newborn period. They were slightly lower, 20.8 +/- 22.1, in those 12.5-18.5 months of age. Suppressions of FFA and subsequent rebounds were in close temporal relation to BS and IRI peaks and lows, but not the GH levels. GH was promptly suppressed by the meal, and in most infants secondary elevations were seen. Untreated marasmic infants had normal or low BS, correspondingly normal or low IRI, markedly elevated FFA (1,821 +/- 588 muEq/liter), and GH levels comparable with those of the control subjects. There was some delay in BS elevation and disappearance and poor insulin release after the meal, with only two of nine having elevations of at least 13 muU /ml The BS elevations and IRI responses, however, were adequate to block FFA release. GH levels were poorly suppressed by the meal but some infants had further elevations, possibly in response to protein. After partial rehabilitation, fasting BS and FFA and BS elevations after the meal were normal. A slight improvement in insulin release was apparent. Fasting GH levels and responses to the meal were normal. Fasting, minimally treated children with marasmic kwashiorkor (MK) had normal or low BS, normal or low IRI, normal FFA, and probably normal GH levels. There was considerable delay in BS elevation, moderately delayed glucose disappearance, and very poor or unmeasurable insulin release after the test meal; FFA and GH were poorly suppressed. After partial rehabilitation, fasting BS was normal, FFA levels were (630 +/- 163 muEq/l), IRI was still low, BS elevations and disappearance improved. IRI responses modestly improved, and GH responses were normal.

Age Factors↗