Biomedical subjects

H Shibata

Publications and source records attributed to H Shibata.

At least 487 records · Page 27Linked to original sources

PubMed1990

Nuclear factor I stimulates transcription of the adenovirus 12 E1A gene in a cell-free system.

Binding to the cis-acting region of NF-I-like protein and/or NF-III-like protein was previously suggested to be responsible for the preferential stimulation of transcription from distal start-site of the adenovirus 12 E1A gene in a cell-free system. In this study, nuclear extracts of Ehrlich ascites tumor cells depleted of NF-I-like protein were found to lose activity to stimulate the E1A gene transcription. This activity was recovered when NF-I purified from HeLa cells with no contamination of NF-III was supplemented. It is thus evident that NF-I is involved in stimulating distal transcription of the adenovirus 12 E1A gene. Moreover, activities for both stimulating the E1A gene transcription and binding to a region recognized by NF-I did not apparently exist in nuclear extracts of a cell line expressing the adenovirus 12 E1A gene. These results suggest that transcription of the adenovirus 12 E1A gene may possibly be autoregulated at least in part through modulation of the activity of NF-I.

Adenoviridae↗

PubMed1990

A rapid turbidimetric immunoassay for serum antistreptolysin-O.

We designed a rapid, quantitative turbidimetric immunoassay for serum antistreptolysin-O (ASO), based on the immunoprecipitating velocity with purified streptolysin-O (SLO), which can be measured turbidimetrically at 340 nm. The assay system involves polyoxyethylene mono-p-nonylphenyl ether to accelerate and enhance the immunoprecipitation reaction. No antibody excess phenomenon is observed, up to 1,700 U/ml. Grossly icteric sera can be assayed. Patient sera gave acceptable results. Free cholesterol offers no interference. The standard curve is linear for values up to 800 U/ml. Results measured by the proposed method and those by the conventional microtitration method correlated well. Analytical recovery averaged 90.1% (80.3%-102.5%). Within-run and day-to-day CVs ranged from 2.1% to 3.5% and from 2.5% to 6.9%, respectively. Working SLO is stable for at least 15 days at 4 degrees C. The proposed method has proven to be superior to other available methods for measuring serum ASO.

Antistreptolysin↗

PubMed1990

Tumor cell adhesion to frozen lymph node sections--a correlate of lymphatic metastasis in breast carcinoma models of human and rat origin.

The role of tumor cell adhesion in lymphatic metastasis of breast cancer was investigated in vitro using a rat mammary carcinoma model of four cell lines with different metastatic phenotypes, two human breast cancer cell lines, and cryostast sections of normal rat or human lymph nodes, respectively. A positive correlation was found between the adhesion levels obtained with three metastatic rat mammary cell lines (TMT-081 greater than MT-100M & TMT-50) and a non-metastatic line MT-W9B, the latter being 3-4 fold less adhesive to the lymph node sections than the metastatic tumors. This selective adhesion was specific, as it was not found with cryostat sections of rat liver and brain. Enzyme assays indicated that cell surface glycoproteins bearing terminal beta-galactoside residues were involved in the adhesion of the rat tumors. Adhesion of the human breast carcinoma cells Hs578T to sections of human lymph nodes was significantly higher than that of the normal breast epithelial cell line Hs578Bst, and comparable to adhesion of a second breast carcinoma line, MCF-7. Moreover, Hs578T cells isolated from regional lymph nodes of tumor-bearing nude mice were significantly more adhesive to human lymph node sections than the parental line. Adhesion of both human and rat tumors could be partially blocked by the addition of the synthetic peptide GRGDSPK and by antibodies directed to the beta 1 chain of integrin, suggesting that an integrin receptor may played a role in the adhesion. The results suggest that tumor cell adhesion to cryostat sections of lymph nodes is a correlate of the malignant phenotype in mammary tumors of diverse origins, and could be used to delineate the adhesion factors mediating lymphatic metastasis.

Animals↗

PubMed1990

Comparative studies on the action of 7-N-[2-[[2-(gamma-L-glutamylamino)ethyl]dithio]ethyl]mitomycin C and of mitomycin C on cultured HL-60 cells and isolated phage and plasmid DNA.

The mechanism of action of a new mitomycin C (MMC) derivative, KT6149, was studied in human leukemia HL-60 cells and in isolated phage and plasmid DNA, and its effects were compared with those of MMC. Cell growth was markedly inhibited by KT6149, with an IC50 of 2 x 10(-9) M, that for MMC being 2 x 10(-8) M. DNA synthesis of HL-60 cells as determined by incorporation of [3H]-thymidine was also inhibited by KT6149, with an IC50 of 2 x 10(-7) M as compared with 2 x 10(-6) M for MMC. RNA and protein synthesis were less markedly inhibited at low concentrations. Alkaline sucrose density-gradient centrifugation revealed a significant decrease in sedimentation velocity for cellular DNA of the cells after 1 h treatment with KT6149 at concentrations higher than 10(-7) M. In contrast, no such change was observed for DNA of cells treated with MMC, even at a concentration of 10(-5) M. In a cell-free system, analysis by agarose gel electrophoresis patterns showed that the drug induced a decrease in the amount of covalently closed circular DNA of phage PM2 and an increase in that of open circular DNA in the presence of dithiothreitol (DTT), whereas MMC did not cause any change in DNA subfraction amounts. Furthermore, the electrophoretic mobility of linearized pBR322 DNA in alkaline agarose gel was significantly decreased by KT6149 in the presence of DTT and FeSO4, no such change being observed in the case of MMC. The results clearly indicate that the inhibitory effects of KT6149 on the growth and DNA synthesis of HL-60 cells are more potent than those of MMC and that KT6149-induced DNA damage is due to single-strand scission and to cross-linking of DNA, suggesting a mode of activation different from that of MMC.

Antineoplastic Agents↗

PubMed1990

Intestinal phosphate transport in spontaneously hypertensive rats and genetically matched controls.

Hypophosphatemia has been documented in patients with hypertension and in spontaneously hypertensive rats compared with genetically matched control Wistar-Kyoto rats. However, renal tubular reabsorption is increased in spontaneously hypertensive rats. Therefore, it was hypothesized that decreased serum phosphate levels in spontaneously hypertensive rats may be related to a decrease in the intestinal transport of phosphate. To test this hypothesis, sodium-dependent phosphate uptake by jejunal brush-border membrane vesicles of spontaneously hypertensive rats and genetically matched Wistar-Kyoto rats was determined. Phosphate uptake consisted of two components: sodium-independent passive diffusion across the brush border and sodium-dependent, carrier-mediated uptake. The initial rate of uptake in spontaneously hypertensive and Wistar-Kyoto rats was linear up to 20 seconds. The initial rate and time course of jejunal sodium-dependent phosphate uptake was decreased in adult spontaneously hypertensive rats compared with corresponding mean values in Wistar-Kyoto rats. This decrease was secondary to a decrease in Vmax rather than Km, suggesting tha the number and/or the activity of the sodium-phosphate transporters is decreased. Sodium-dependent phosphate uptake was pH dependent, with greater uptake at pH 6.0 than at pH 7.4. However, uptake values were lower in spontaneously hypertensive rats than in Wistar-Kyoto rats at all pH levels tested. In contrast, sodium-dependent phosphate uptake in weanling rats (prehypertensive state) was not significantly different between spontaneously hypertensive and Wistar-Kyoto rats. Vitamin D deficiency in both spontaneously hypertensive and Wistar-Kyoto rats decreased Vmax and Km of sodium-dependent phosphate uptake, whereas 1,25(OH)2 vitamin D3 administration increased Vmax and Km in both spontaneously hypertensive and Wistar-Kyoto rats. These results suggest that the hypophosphatemia seen in adult spontaneously hypertensive rats is secondary to a decrease in sodium-dependent phosphate uptake compared with controls. The sodium phosphate transporter in spontaneously hypertensive rats is responsive to vitamin D administration.

Animals↗

PubMed1990

Iodoacetic acid-induced rigor in ileal longitudinal smooth muscle of guinea-pig.

1. Ileal tensions to iodoacetic acid (IAA) develop when tissue ATP concentration falls below approximately 60-55% of the control. 2. As the IAA concentration is increased (0.1-10 mM), the ATP concentrations decrease rapidly, and both the time of the onset and the duration of the contraction shorten. 3. In the presence of lactate, IAA failed to decrease the tissue ATP concentration and did not develop tension. 4. The contraction to IAA developed in the presence of Ca2+ antagonist, D-600 or in Ca2(+)-free solution, however, onset time was prolonged. 5. These results suggest that the contraction to IAA is referred to as 'rigor' because it increases with decreasing tissue ATP concentration in ileum.

Adenosine Triphosphate↗

PubMed1990

Three-dimensional analysis of facial morphology using moiré stripes. Part I. Method.

A system is presented for analysing facial morphology using moiré stripes. Faces are photographed with a moiré camera, the moiré stripes are entered into a computer, and the computer automatically analyses the dimensions of the face. Subtle differences between the right and left sides of the face appear as asymmetries in the moiré pattern and are easily identified. The method is useful for analysing maxillofacial deformities, for treatment planning, and assessment of postoperative results.

Cleft Lip↗

PubMed1990

Three-dimensional analysis of facial morphology using moiré stripes. Part II. Analysis of normal adults.

This paper presents a system for analysing facial morphology using moiré stripes in 60 normal Japanese high-school students. Analysis of the central region of the face revealed consistent differences between the sexes and between the right and left sides of the face. On the basis of these data, it is suggested that 1 mm difference should be considered permissible between the 2 sides of the upper lip in cases of lip repair in cleft lip and palate patients.

Adolescent↗

PubMed1990

Kinetics of hydroperoxide degradation by NADP-glutathione system in mitochondria.

Hydroperoxide decomposition by the NADP-glutathione system in rat liver mitochondria was analyzed. Mitochondria were found to contain high concentrations of the reduced form of glutathione (GSH) (4.32 +/- 0.50 nmol/mg) and NADPH (4.74 +/- 0.64 nmol/mg), and high activities of glutathione peroxidase and reductase. In the initial phase of the reaction, the rate of hydroperoxide decomposition was proportional to both the GSH level and the activity of GSH peroxidase. However, in the later steady state, the step of NADP reduction was rate-limiting, and the overall reaction rate was independent of the initial concentration of GSH, and activities of glutathione peroxidase and reductase. Some GSH was released from mitochondria during incubation, but the rate of the decomposition could be simply expressed as kappa [GSH]/2, where kappa is the first-order rate constant of the peroxidase and [GSH] is the intramitochondrial level of GSH in the steady state. The rate of the reaction in the steady state was also dependent on the NADPH level, its reciprocal being linearly correlated with [NADPH]-1. The rate of decomposition of hydroperoxide was influenced by the respiratory state. During state 3 respiration, the rate was greatly depressed, but was still considered to exceed by far the rate of physiological generation of hydroperoxide.

Animals↗

PubMed1990

Intestinal calcium transport in spontaneously hypertensive rats and their genetically matched Wistar-Kyoto rats. I. Endoplasmic reticulum.

The present study was designed to investigate calcium uptake by the intestinal endoplasmic reticulum in the spontaneously hypertensive rat (SHR) and its genetically matched normotensive control, the Wistar-Kyoto rat (WKY). The calcium uptake was characterized before (weanling) and after (adult) development of hypertension in SHR and their age-matched WKY controls. Adenosine 5'-triphosphate (ATP)-driven calcium uptake with time was stimulated several-fold compared with the no-ATP condition, and the maximal uptake occurred after 15 min in both SHR and WKY. The maximal ATP-dependent calcium uptake was significantly greater in the intestinal endoplasmic reticulum of adult SHR than in that of WKY (P less than 0.05). The initial rate of calcium uptake was linear up to 30 s in both SHR and WKY. The kinetics of ATP-dependent calcium uptake at a concentration between 0.1 and 1.0 mumol/l showed a maximal uptake (Vmax) of 1.89 +/- 0.3 and 1.06 +/- 0.1 nmol/mg protein per 15 s for adult SHR and WKY, respectively (P less than 0.02), and binding constant (Km) values of 0.15 +/- 0.08 and 0.12 +/- 0.05 mumol/l, respectively. The ontogeny of calcium uptake by intestinal endoplasmic reticulum was characterized before the development of hypertension in weanling (3-week-old) SHR and WKY. In both SHR and WKY weanlings, calcium uptake by the intestinal endoplasmic reticulum was enhanced several-fold by the presence of ATP compared with the no-ATP condition, and the maximal uptake occurred after 15 min. The maximal ATP-dependent calcium uptake was significantly greater in 3-week-old SHR than in age-matched WKY (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗

PubMed1990

Increase in the level of P-glycoprotein mRNA expression in multidrug-resistant K562 cell lines treated with sodium butyrate is not accompanied with erythroid differentiation.

We examined the effect of hemin, sodium butyrate and mitomycin C on levels of P-glycoprotein mRNA in human myelogenous K562 cells by northern blot analysis. After treatment with sodium butyrate a dose-dependent increase of P-glycoprotein mRNA expression was observed in the adriamycin-resistant K562 and vincristine-resistant K562 lines. With 10 mM sodium butyrate, the level of P-glycoprotein mRNA reached 20 times that of control adriamycin-resistant K562 and with 30 mM sodium butyrate, it exceeded 5 times that of control vincristine-resistant K562. In contrast, hemin and mitomycin C had almost no effect on P-glycoprotein mRNA. In this experiment, since expression of P-glycoprotein mRNA was not necessarily accompanied with induction of erythroid differentiation, the increased amount of P-glycoprotein mRNA is unlikely to be a result of differentiation.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1990

Double-blind test of human urinary macrophage colony-stimulating factor for allogeneic and syngeneic bone marrow transplantation: effectiveness of treatment and 2-year follow-up for relapse of leukaemia.

A randomized, double-blind placebo-controlled phase III clinical trial was performed to study the effects of human urinary macrophage colony-stimulating factor (hM-CSF) after allogeneic and syngeneic bone marrow transplantation (BMT) in 60 hM-CSF treated and 59 placebo control patients. HM-CSF was administered at a daily dose of 2 x 10(5) units/kg from day 1 to day 14 after BMT. Significant differences between hM-CSF and control patient were found in the recovery time to greater than 0.5 x 10(9) granulocytes/l and the survival rate during the initial 120 d without retransplantation. There was no difference in the incidence or grade of graft-versus-host disease (GVHD). There was no difference in the rate of leukaemic relapse at 24-36 months after BMT in patients with acute lymphocytic, acute nonlymphocytic, or monocytic leukaemia. The results of this trial show that human M-CSF improves the outcome of BMT without any influence on the occurrence of leukaemic relapse or GVHD.

Adolescent↗

PubMed1990

The pharmacokinetics and pharmacodynamics of a new thromboxane synthetase inhibitor, 6-(1-imidazolylmethyl)-5,6,7,8-tetrahydronaphthalene-2-carboxylic acid (DP-1904) in man after repeated oral doses.

The pharmacokinetics of DP-1904, a new potent and selective thromboxane synthetase inhibitor, and its effects on ex-vivo prostanoid formation have been studied in groups of Japanese normal male volunteers, who received repeated oral doses of 200 mg every 12 h for 4 doses, or 400 mg every 24 h for 2 doses, or 200 mg every 12 h for 14 doses. The drug was well tolerated by all subjects without evidence of adverse reactions. Repeated administration showed no significant changes in half-lives, tmax values, cmax values and AUC values. DP-1904 did not exhibit time-dependent kinetics. Its plasma levels were lower than the quantifiable level (50 ng mL-1) at 12 h after each dose. These data suggest no significant accumulation of DP-1904 in normal volunteers. DP-1904 reduced the serum thromboxane B2 by about 80% during the medication, the serum concentrations returning to about 44, 75 and 20% of the predrug control values at 36 h after the last 200 mg doses and 48 h after the last 400 mg dose.

Administration, Oral↗

PubMed1990

[Actual conditions of bacterial infection associated with hematopoietic disorders--changes in 10 years. The Hanshin Study Group of Hematopoietic Disorders and Infections].

This study showed several accumulated data through ten years from our experience in hematopoietic disorders and associated infections, which has been analyzed by the Hanshin Study Group of Hematopoietic Disorders and Infections. Since 1979 to 1988, our group had evaluated the sorts of causative organisms and the efficacy of various antibiotics therapy in 2119 cases of infectious diseases associated with hematopoietic disorders. On behalf of evaluating the changes of disease profile for ten years, we divided the accumulated data into three phases; former phase the first three years, middle phase the second three years and late phase the last four years. There was no significant difference in the frequency of various hematopoietic disorders among the three phases. Each leukemia patients occupied 77% of all cases. Sepsis suspected is the most frequent infectious disease accounting for 68.8%. The other infectious diseases were 8.4% of the sepsis, 14.8% of the respiratory infections and 3.1% of the urinary tract infections. Comparing the frequency of infections among the three phases, the respiratory and urinary tract infections inclined to decrease. Of the 532 strains isolated from 2119 cases and identified as causative organisms, gram-negative bacilli occupied 62.8% and gram-positive bacteria 36.5%. In comparing the percentage of gram-negative bacilli among the three phases, it showed a decreasing tendency in order former phase 63.6%, middle phase 76.4% and late phase 43.8%. Pseudomonas, however, had been isolated at almost constant ratio through ten years. On the other hand, the ratio of gram-positive bacteria isolated were 34.5% in former phase, 23.6% in middle phase and 56.3% in late phase, showing increasing a tendency through the period. Twenty-three kinds of antibiotics were administered by intravenous drip infusion. The efficacy rate was 43.9% to 67.2%. In particular, effectiveness of antibiotic therapy often depends on the change of peripheral neutrophil counts from the onset and during the therapy. The efficacy rate, however, was 36% even neutrophil counts have not shown the tendency of increase from less than 100/microliters.

Adolescent↗

PubMed1990

Is macronodular liver cirrhosis an irreversible lesion? Changes in the intrahepatic micro-vasculature treated with estradiol benzoate in rats.

Estradiol benzoate (EB), a synthetic estrogen, was injected to macronodular cirrhotic rats, and the reversibility of the lesion was investigated. Macronodular liver cirrhosis (MNLC) was produced by use of carbon tetrachloride plus 3'-Me-DAB. In animals with no treatment, regenerative nodules remained unchanged during an eighteen-week observation period. Microangiograms showed markedly deranged intrahepatic microvasculatures, including an irregularly contoured vascular tree and rarefaction in the peripheral area. On the other hand, EB treatment exerted conspicuous efficacy on the above-mentioned intrahepatic microcirculatory disorder and on sinusoidal dilatation, which led the livers with MNLC to revert to almost normal appearance. It is concluded that EB provides a salutary effect on the intrahepatic microcirculatory system, by means of which MNLC can be shown to be a reversible lesion.

Animals↗

PubMed1990

Ontogeny of calcium transport by intestinal Golgi in spontaneously hypertensive rats and genetically matched WKY rats.

Our studies were designed to characterize calcium transport by intestinal Golgi vesicles in spontaneously hypertensive rats (SHR) and their genetically matched control, Wistar-Kyoto rats (WKY). The biochemical purity of the intestinal Golgi in SHR and WKY was validated by marker enzyme studies. Calcium uptake by Golgi vesicles represented transport into the intravesicular space as evidenced by temperature dependency and by calcium ionophore A23187-induced calcium efflux experiments. ATP-driven calcium uptake was stimulated several-fold compared with uptake in the absence of ATP and adenylyl-(beta-gamma-methylendiphosphate) (nonhydrolyzable ATP) in both SHR and WKY. ATP-dependent calcium uptake was significantly higher in WKY compared with SHR at early times points, 15 s-5 min (p less than 0.05-0.01). The initial rate of calcium uptake was linear up to 60 s. Kinetic parameters of calcium uptake at free calcium concentrations of 0.1 to 2.0 microM showed a Vmax of 1.64 +/- 0.06 and 1.2 +/- 0.06 nmol.mg protein-1.15 s-1 in WKY and SHR, respectively (p less than 0.01), and the Km values were 0.17 +/- 0.03 and 0.16 +/- 0.04 microM, respectively. Kinetic analysis of ATP-dependent calcium uptake in 3-wk-old rats showed a Vmax of 0.07 +/- 0.005 and 0.36 +/- 0.05 nmol/mg protein-1.15 s-1 (p less than 0.01) and a Km of 0.26 +/- 0.08 and 0.4 +/- 0.2 microM in SHR and WKY, respectively. These results suggest that intestinal Golgi vesicles in SHR and WKY demonstrate an ATP-driven calcium uptake. This ATP-dependent process is significantly decreased in the weanling and adult SHR compared with WKY. Such an abnormality in intracellular calcium regulation may have a role in the development of hypertension.

Adenosine Triphosphate↗

PubMed1990

[Augmentation of pirarubicin cytotoxicity by chlorpromazine in doxorubicin-resistant mouse P388 leukemia cells].

The intracellular uptake, retention and cytotoxicity of pirarubicin, an anthracycline derivative, combined with chlorpromazine were investigated in doxorubicin-resistant mouse P388 leukemia (P388/DXR) cells. The number of viable cells was determined by the dye exclusion method. Chlorpromazine increased the cytotoxicity of pirarubicin in a dose-related manner in P388/DXR cells. A similar dose-response relationship was observed for chlorpromazine in increasing net intracellular pirarubicin accumulation. The accumulation was based on block of enhanced pirarubicin efflux from resistant cells by chlorpromazine. However, chlorpromazine did not affect cytotoxicity or transport of pirarubicin in the drug-sensitive cell line. The possible mechanisms of the restoration of pirarubicin sensitivity in P388/DXR cells by chlorpromazine are discussed.

Animals↗

PubMed1990

Induction of prolonged elevation of interleukin 2 in the culture medium of murine splenocytes by their precultivation before mitogenic stimulations and its potentiation by glucocorticoid treatment and restraint stress loading.

Enhancement of interleukin 2 (IL 2) activity in the culture medium of splenocytes of BALB/c mice occurred if the cells were precultured before concanavalin A (Con A) and phytohemagglutinin stimulation. This enhancing effect was much greater in autoimmune NZB/W F1 mice than BALB/c mice, the induced high level of IL 2 being sustained for 11 days of culture. The continuously elevated IL 2 activity induced by precultivation was lowered by the addition of the intact normal thymocytes, but not by precultured or irradiated thymocytes. Lipopolysaccharide-induced anti-DNA antibody production in the precultured splenocytes of NZB/W F1 mice was higher than that in freshly prepared ones. Mitogen-induced proliferative responses in both freshly prepared thymocytes and splenocytes of BALB/c mice treated with hydrocortisone (HC) were significantly enhanced, although the number of splenocytes and the primary in vitro plaque-forming cell response to sheep erythrocytes were reduced. Con A-induced IL 2 elevation in the supernatant of splenocytes precultured before the antigen stimulation was potentiated in HC-treated mice. Similar results were obtained in splenocytes from BALB/c mice loaded with restraint stress. These findings suggest that disturbance of IL 2 metabolism might be involved in the pathogenesis of NZB/W F1 mice, and an increased level of glucocorticoids might lead to a condition in which the body becomes susceptible to the development of hyper-immune responses.

Animals↗