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Biomedical subjects

H Ohmori

Publications and source records attributed to H Ohmori.

At least 325 records · Page 18Linked to original sources
PubMed1984

Mechanoelectrical transducer has discrete conductances in the chick vestibular hair cell.

Properties of mechanoelectrical transduction were studied at the single-cell level by applying a whole-cell recording variation of the patch-clamp technique to dissociated vestibular hair cells of chicks. The hair bundle was directly stimulated by a glass rod, and transduction currents were recorded from the cell body. After a triangular movement of the stimulating probe, the transduction current was generated stepwise between discrete levels of amplitude. The minimum step amplitude was -1.8 pA at -27 mV in Na-containing normal saline.

Animals↗
PubMed1984

Studies of ionic currents in the isolated vestibular hair cell of the chick.

The ionic currents in enzymatically isolated vestibular hair cells of the chick were studied by a whole-cell-clamp variation of the patch voltage clamp, and by single channel recording. At membrane potentials more negative than -80 mV the hair cell showed anomalous rectification, and at potentials more positive than -40 mV large outward K currents were observed in normal saline. The outward K current decreased at large positive potentials, showing an N-shaped I-V relation. The outward K current was carried mostly through the Ca-activated K channel. K currents through the anomalous rectifier channel showed a decay in normal saline. This decay was eliminated reversibly in Na-free saline when the isotonic KCl-EGTA solution was used as the internal medium. However, a fast decay was still observed in Na-free high-K external solution when isotonic CaCl-EGTA was used as the internal medium. An increase in [K]o decreased the decay rate of the inward K current. The single-channel conductance of the anomalous rectifier channel was 50 pS in 160 mM-K saline and 23 pS in 40 mM-K saline. In 100 mM-Ca, -Sr and -Ba salines a large inward current was observed. At positive potentials the inward current carried by Ca and Sr ions showed significant decay; the current became outward at large positive potentials. Since the decay of the inward current was eliminated when 100 microM-quinine was added to the bathing medium, it was probably due to the activation of some Ca-activated K conductance which remained even with isotonic CsCl-EGTA internal medium. The activation kinetics of the Ca channel were studied in 100 mM-Ba solution at low temperatures (9-13 degrees C). From a comparison of the time constants of activation with the time constants of the tail currents, it was concluded that the Ca channel follows Hodgkin-Huxley-type m2 kinetics. A slow component that deviated from m2 kinetics was frequently observed at relatively large positive potentials. The steady-state fluctuations of Ba current showed a power density spectrum reasonably well fitted by a sum of two Lorentzian functions. The spectrum has a low-frequency component which indicates kinetics close to the macroscopic activation process of the Ca channel and a high-frequency component that indicates very fast flickering kinetics operating in the Ca channel.

Action Potentials↗
PubMed1984

Malignant fibrous histiocytoma originating in the left spermatic cord with a review of 14 cases in the literature.

An 84-yr-old man developed a small-finger-tip sized tumor in the left inguinal area about five to six years prior to consultation with the Urology Department. Later, the tumor extended to the scrotum and the suprapubic area. Histological examination of an en block specimen showed the tumor to be a malignant fibrous histiocytoma of spermatic cord origin. Fourteen cases in the worldwide literature are reviewed, and characteristics of malignant fibrous histiocytoma at this particular site are discussed.

Aged↗
PubMed1984

[Intravesical chemotherapy for superficial bladder tumors].

Intravesical chemotherapy is one of the most effective treatments for superficial bladder tumors. Recent progress in the development of chemotherapeutic agents has provided a variety of compounds of potential benefit for intravesical administration in cases of superficial bladder tumors, including thio-TEPA, MMC, carboquone, adriamycin, FT-207, cytosine arabinoside and bleomycin, and the in therapeutic effectiveness has been reported. We selected adriamycin, because it is considered suitable for intravesical instillation. A 68% effectiveness has been experienced for instillation repeated six to nine times (adriamycin 50 mg/normal saline 30 ml) and side effects occurred in 23% of patients. Intravesical chemotherapy has also been attempted to prevent recurrence after conservative therapy but these modalities still seem to need further study.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1984

[Comparative studies of DL-8280 and pipemidic acid in complicated urinary tract infections by double-blind method].

The clinical efficacy, safety and usefulness of DL-8280 for the treatment of complicated urinary tract infections were compared with those of pipemidic acid (PPA) by a double-blind method. DL-8280 and PPA were orally administered at a daily dose of 600 mg (t.i.d.) and 2.0 g (q.i.d.) for 5 days, respectively. Of the 311 patients who received DL-8280 or PPA, clinical efficacy, safety and usefulness were evaluated in 228 patients (DL-8280, 115; PPA, 113), 306 patients (DL-8280, 153; PPA, 153) and 250 patients (DL-8280, 124; PPA, 126), respectively. There was no significant difference in the background characteristics between the two groups. In the DL-8280 group the overall clinical efficacy was excellent in 39.1% and moderate in 41.7%, the effectiveness rate being 80.9%, whereas in the PPA group it was excellent in 23.9% and moderate in 33.6%, the effectiveness rate being 57.5%. The efficacy in the DL-8280 group was significantly higher than that in the PPA group (P less than 0.001). According to classification by the type of infection, the overall clinical efficacy of DL-8280 in groups except group 2 (monomicrobial infection, post prostatectomy) and group 3 (monomicrobial infection, upper urinary tract infection) was superior to that of PPA, the difference being significant. Pyuria was cleared or improved in 59.1% of the patients treated with DL-8280 and in 46.0% of the patients with PPA. The difference was not significant. Bacteriuria was eliminated in 76.5% in the DL-8280 group and in 50.4% in the PPA group. DL-8280 demonstrated a significantly higher response than PPA (P less than 0.001). Of the bacteria isolated from the DL-8280 group and PPA group 89.0% and 72.1%, respectively, were eradicated after the treatment, a significant difference being observed between the two groups (P less than 0.001). The clinical efficacy evaluated by the doctor in charge was excellent in 46.1% and good in 37.4% of the patients treated with DL-8280 and excellent in 26.5% and good in 34.5% of the patients treated with PPA, the intergroup difference in the efficacy being significant (P less than 0.001). The evaluation of usefulness of DL-8280 and PPA was "satisfactory" for 71.8% and 47.6%, respectively, the difference being significant (P less than 0.001). Side effects were observed in 11 patients (7.2%) in the DL-8280 group and in 12 patients (7.8%) in the PPA group, but none were serious.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗
PubMed1984

[Clinical studies on intravenous drip-infusion of micronomicin for complicated urinary tract infections].

The clinical efficacy and safety of intravenous micronomicin (MCR) therapy were evaluated in cases with complicated urinary tract infections. MCR was administered to 13 patients by intravenous drip infusion over a period of 1 hour, in a dose of 120 mg twice daily for 5 consecutive days. Therapeutic results were evaluated by the criteria proposed by UTI committee and the judgement of the doctor in charge and the overall clinical efficacy rate was 69% (9/13) and 85% (11/13), respectively. Among 18 strains isolated before treatment, 15 strains were eradicated and bacteriological efficacy rate was 83%. No side effects including nephrotoxicity and ototoxicity associated with the treatment were noted, except for 1 case with transient elevation of A1-P.

Adult↗
PubMed1984

[Intravesical chemotherapy with 4'-Epi-Adriamycin in patients with superficial bladder tumors].

Intravesical instillation of anticancer agents is one of the most effective methods for treating superficial bladder cancer. We evaluated the effects of including 4'-Epi-Adriamycin, a derivative of Adriamycin, in intravesical instillation chemotherapy. Thirty-five patients with superficial bladder tumors were treated with 4'-Epi-Adriamycin. The patients received 2 courses of 3 consecutive daily instillations of 50-80 mg 4'-Epi-Adriamycin dissolved in 30 ml of physiological saline, with an interval of 4 days. Of the 33 cases which could be fully evaluated, complete regression was observed in 4 cases and partial regression (greater than 50%) in 14 cases, showing an effectiveness rate of 55%. Side effects such as pollakisuria and miction pain occurred in 9 cases. The rate of effectiveness of this treatment was approximately equivalent to the results that we reported using Adriamycin and the occurrence and degree of side effects were lower.

Adult↗
PubMed1984

[Prostatic tissue and fluid levels of DL-8280].

The concentration of DL-8280, a new pyridone carboxylic acid, in the prostatic tissue and fluid after oral administration to man was studied. The drug was concentrated in the prostate and the concentration was dose-dependent. The ratios of prostatic tissue and fluid levels to serum levels were 1.62-1.79 and 1.65-1.96. respectively.

Administration, Oral↗
PubMed1983

[R 1881 binding receptor and DHT concentrations in prostatic cytosol].

R 1881 binding receptor and DHT concentrations in human prostatic cytosol were assayed in surgically removed prostatic tissues of benign prostatic hyperplasia (BPH) and of the normal prostate. The normal prostates were obtained from totally cystectomized male patients with bladder cancer. Cytosols were incubated with 0.25--8.0 nM (6 points) of 3H-R 1881 in the presence or absence of excess radioinert R 1881 at 4 degrees C for 20 hours, thereafter treated with 0.5% dextran coated charcoal. Specific bindings were analysed in the form of scatchard plot analysis. Cytosol DHT levels were determined by radioimmunoassay reported previously. Steroid specificity studies revealed that R 1881 binding receptor was inhibited not only by androgens but also by progesterone, however, an addition of 1000 fold excess triamcinolone acetonide (TCA) reduced the inhibition by progesterone. As R 1881-receptor complex was eluted at the void volume of sephacryl S-200 chromatography, the receptor was considered to be 8-9S protein. Cytosol DHT levels were 35.5 +/- 13.6 pg/mg cytosol protein in BPH and 18.9 +/- 7.1 pg/mg protein in the normal prostates, showing a significantly higher value in the former (p less than 0.01). Kd and NBS of R 1881 receptor in BPH were 0.73 +/- 0.21 nM and 30.1 +/- 9.0 fmol/mg cytosol protein and those in normal prostate were 0.68 +/- 0.28 nM, 10.2 +/- 4.2 fmol/mg protein, respectively. NBS were also higher in BPH compared to the normal prostate (p less than 0.001). Moreover, DHT levels (y) and NBS (x) showed a significant correlation (y = 0.631 X + 15.764, r = 0.506).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1983

Mechanism of augmentation of the antibody response in vitro by 2-mercaptoethanol in murine lymphocytes. II. A major role of the mixed disulfide between 2-mercaptoethanol and cysteine.

Five thiol compounds including 2-mercaptoethanol (2-ME) were examined for their augmenting effects on in vitro antibody response to sheep erythrocytes. Three compounds were effective with the following order of activity; 2-ME greater than dithiothreitol greater than cysteamine. Glutathione and thioglycollate failed to enhance the response. The same order or effectiveness was seen in the stimulation of [35S]cystine uptake by murine lymphocytes by these thiols. Murine lymphocytes took up cysteine five to six times more rapidly than cystine. It is, however, unlikely that 2-ME stimulation of cystine uptake is solely due to the reduction of cystine into cysteine, because 2-ME was still stimulatory after free thiol groups had disappeared in the medium containing 2-ME and [35S]cystine. The mixed disulfide of cysteine with 2-ME (Cys-2-ME) was found to be an only product after free thiols had been oxidized. [35S]Cys-2-ME was taken up by the lymphocytes with a comparable rate to cysteine via a transport system common to that of leucine and phenylalanine. Cysteine was, however, transported via a different route. It was observed that Cys-2-ME was readily metabolized to cysteine and glutathione after the uptake. Cys-2-ME added to cystine-free RPMI 1640 medium could support the antibody response as efficiently as cystine plus 2-ME. These observations strongly suggest that 2-Me stimulates cystine uptake and, therefore, enhances the antibody response through the formation of the mixed disulfide with cysteine.

Adjuvants, Immunologic↗
PubMed1983

Mechanism of augmentation of the antibody response in vitro by 2-mercaptoethanol in murine lymphocytes. III. Serum-bound and oxidized 2-mercaptoethanol are available for the augmentation.

The fetal calf serum (FCS) that was incubated with 2-mercaptoethanol (2-ME) followed by the removal of free 2-ME could support the antibody response to sheep erythrocytes in vitro as effectively as native FCS plus 2-ME. The supporting activity of 2-ME-pulsed FCS was reversibly abrogated by the treatment with dithiothreitol followed by dialysis. In addition, iodoacetamide-treated FCS did not acquire the supportiveness by 2-ME pulsing. These observations suggest that the activity of 2-ME-pulsed FCS would be due to the mixed disulfide between 2-ME and FCS components. On the other hand, the disulfide form of 2-ME (2-MEox) could also augment the antibody response as effectively as fresh 2-ME (the reduced form). These derivatized forms of 2-ME as well as fresh 2-ME was found to stimulate the transport of [35S]cystine into murine lymphocytes when the uptake was examined by the long-term experiments (24 hr). These stimulations were thought to be mediated by the formation of the mixed disulfide between 2-ME and cysteine because the lymphocytes promoted the reaction of [35S]cystine with 2-MEox- or 2-ME-pulsed FCS to produce the mixed disulfide that had been shown to be taken up by the lymphocytes four to five times more rapidly than cystine. Therefore, it was suggested that 2-MEox, and 2-ME-pulsed FCS could augment the antibody response in a similar fashion to 2-ME by stimulating the uptake of cystine, an essential amino acid.

Adjuvants, Immunologic↗
PubMed1983

Intravesical adriamycin chemotherapy in bladder cancer.

In an experimental study undertaken to elucidate the mechanism whereby Adriamycin (ADM) instilled into the bladder produces its side-effects, the time course of ADM concentration in blood, urine, and tissues of various organs, and also histopathological changes in the bladder mucosa were investigated in normal adult dogs that had undergone bilateral ureterostomy and then received intravesically instilled ADM. Clinically, ADM was used in the treatment of superficial bladder tumors in an attempt to facilitate the transurethral operative procedure. A total of 261 patients were included in this trial. ADM was instilled into the bladder at the following dosages: 1,000 micrograms/ml (30 mg ADM per 30 ml physiological saline), 1,600 micrograms/ml (50 mg ADM per 30 ml physiological saline), and 2,000 micrograms/ml (60 mg ADM per 30 ml physiological saline). The rate of effectiveness was 32%, 66%, and 60%, respectively. The incidence of side-effects was 29%, 20%, and 45%, respectively. The systemic uptake of the drug was small and the side-effects were pain an micturition, pollakiuria, and urgency. From the aspects of efficacy and toxicity, 1,600 micrograms/ml was found to be the optimal dosage.

Aged↗