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H Muranishi

Publications and source records attributed to H Muranishi.

13 recordsLinked to original sources
PubMed1992

Uptake of fractionated [3H]heparin by rat parenchymal hepatocytes in primary culture: effects of alpha-globulin, temperature, and pH.

The mechanism of uptake of fractionated [3H]heparin in conjunction with the effect of alpha-globulin (the major binding protein of heparin) was investigated in primary cultures of rat parenchymal hepatocytes. The uptake clearances were estimated from the initial linear phase, up to 1 min, of the uptake-versus-time profile. The uptake clearance for fractionated [3H]heparin was 11.0 mL/min/g of liver at 7.5 nM fractionated [3H]heparin in the absence of alpha-globulin. This value decreased with increasing concentration of alpha-globulin in the incubation solution, a fact suggesting that the rate of uptake of alpha-globulin-bound, fractionated [3H]heparin is lower than that of unbound [3H]heparin, as generally assumed for hepatic drug elimination. However, the uptake clearance in the presence of alpha-globulin at 8 mg/mL, where free, fractionated [3H]heparin was supposed to be negligible according to the results of our in vitro study, was approximately 12% of that in the absence of alpha-globulin. These results suggest that alpha-globulin-bound, fractionated [3H]heparin also contributes to the uptake of fractionated [3H]heparin. This effect on uptake could be explained by the protein-mediated transport concept rather than the traditional assumption that protein-bound drugs are not transported. The uptake clearance was reduced significantly by reducing the incubation temperature from 37 to 4 degrees C. However, neither the pH of the incubation solution (6.4-8.4) nor several inhibitors of active transport had any clear effects on the uptake clearance.

Alpha-Globulins↗
PubMed1992

Time-dependent alterations of leukotriene production and catabolism in rat peritoneal macrophages following intraperitoneal injection of thioglycollate broth.

Alterations of leukotriene (LT) productivity in peritoneal macrophages (PM) from untreated rats (control) as well as from rats treated i.p. with thioglycollate broth (TG) were investigated on days 3, 7 and 14 after TG administration. The resident PM from the untreated rats produced mainly LTB4 and 5-HETE with small amounts of 12-HETE and LTD4 with only a trace of LTC4 when stimulated with the calcium ionophore A23187. The PM elicited from rats on days 3 and 7 produced more LTC4 than did the resident PM but fewer other lipoxygenase metabolites. On day 14, however, the elicited PM resembled the resident PM in terms of lipoxygenase metabolite production. Similar results were achieved in the presence of arachidonic acid and A23187. A decrease in lipoxygenase metabolism in the elicited PM was also suggested by using opsonized zymosan. Catabolism studies indicated a reduction in r-glutamyl transpeptidase activity in the elicited PM and suggested a reduction in catabolism for LTB4 in the former cells. The authors conclude that the TG-elicited PM generate fewer lipoxygenase metabolites than the resident PM following stimulation, but show a preferential conversion of LTA4 to sulfidopeptide LTs rather than to LTB4. The elicited PM also show a reduced catabolism for LTC4 and LTB4.

Animals↗
PubMed1992

Macromolecule-macromolecule interaction in drug distribution. II. Effect of alpha-globulin on saturable uptake of fractionated [3H]heparin by rat parenchymal hepatocytes in primary culture.

The uptake of fractionated [3H]heparin was investigated in rat parenchymal hepatocytes in primary culture. The initial uptake of fractionated [3H]heparin was found to be saturable with the maximum uptake velocity (Vmax) of 10.1 +/- 1.46 pmol/min/mg protein and the Michaelis constant (Km) of 284 +/- 47.9 nM. The effect of alpha-globulin, the major protein binding to fractionated [3H]heparin, on the saturable uptake profile of fractionated [3H]heparin was also investigated. The uptake clearance was reduced, depending on the concentration of fractionated [3H]heparin, by the addition of 1 mg/ml alpha-globulin. We assumed that fractionated 3H-heparin bound to alpha-globulin was not available for uptake and that the reduction in the uptake clearance was solely attributable to the saturable binding of fractionated [3H]heparin to alpha-globulin. The uptake clearance versus concentration profile was analyzed to obtain the dissociation constant (Kd) of 31.8 nM and the capacity (n) of 0.047 for the binding of fractionated [3H]heparin to alpha-globulin. The saturable binding of fractionated [3H]heparin to alpha-globulin was supported by in vitro binding experiments using gel chromatography, in which bound fractionated [3H]heparin decreased with the concentration of fractionated [3H]heparin in the presence of alpha-globulin. In conclusion, the present study demonstrated the saturable uptake of fractionated [3H]heparin by rat parenchymal hepatocytes and the saturable binding of fractionated [3H]heparin to alpha-globulin. The saturable uptake may suggest the involvement of a specific transport system such as receptor-mediated endocytosis.

Alpha-Globulins↗
PubMed1992

Simultaneous measurements of adenosine deaminase activity and tuberculostearic acid in pleural effusions for the diagnosis of tuberculous pleuritis.

Adenosine deaminase (ADA) activity and tuberculostearic acid (TSA) levels in pleural effusions were measured in 18 patients with active tuberculous pleuritis, 16 patients suspected of having tuberculous pleuritis, 14 patients with carcinomatous pleuritis, and 19 patients suffering from pleuritis of non-malignant and non-tuberculous etiology. In the patients with active tuberculous pleuritis, ADA was elevated in 56% and TSA was positive in 78%. In 83% of these patients, either ADA was elevated or TSA was positive. ADA was elevated together with a positive TSA in 50%. In contrast, TSA was positive in only 6% and ADA was elevated in 24% of the patients with non-tuberculous pleuritis, and none of these patients showed the combination of an elevation of ADA and a positive TSA. These results suggest that simultaneous measurements of both ADA and TSA in pleural effusions are useful for the diagnosis of tuberculous pleuritis.

Adenosine Deaminase↗
PubMed1992

Stereotactic radiosurgery using a linear accelerator.

A basic and clinical study of radiosurgery using the linear accelerator (Linac) system for unremovable deep-seated brain tumors is reported. A Komai stereotactic ring was used to locate the target coordinates. The patient was laid on the Linac treatment table and held in the head fixation system. Irradiation was given in five positions. The dose profile by film dosimetry and Rando phantom was satisfactory. Seventeen tumors in 14 patients were treated. Clinical or histological diagnoses were nine metastases, one benign and two malignant gliomas, one meningioma, and one craniopharyngioma. Tumor sizes were between 8 and 30 mm. Doses were between 12 and 30 Gy. Computed tomographic evaluation after 3 months of 12 tumors in 11 survivors showed one complete remission, three partial remission, six no change, and two partial deterioration. For progressive tumors, Linac radiosurgery results are excellent.

Adult↗
PubMed1990

Enhanced leukotriene C4 synthase activity in thioglycollate-elicited peritoneal macrophages.

The utilization of LTA4 by peritoneal macrophages (MO) obtained from untreated rats (control) as well as by those elicited from rats was investigated at designated intervals (on days 3, 7, and 14) following the intraperitoneal injection of thioglycollate (TG). On day 7 following the injection the elicited MO converted LTA4 to LTC4 at the highest rate while the resident MO showed the lowest rate. The conversion of LTA4 to LTC4 and LTB4 was next examined by using each MO lysate. The apparent LTC4 synthase activity was significantly higher in the MO lysate both on day 3 and day 7, with the latter being the highest value obtained. The GSH S-transferase activity in each lysate using as the substrate, DNCB was significantly lower on day 3 but significantly higher on day 7 as compared to control values. However, this elevated activity was less variable than that observed with LTC4 synthase. The possible implication for these observations is discussed.

Animals↗
PubMed1990

Macromolecule-macromolecule interaction in drug distribution: effect of alpha-globulin concentration on the hepatic uptake of fractionated 3H-heparin by perfused rat liver.

The effect of alpha-globulin, the dominant binding protein for fractionated 3H-heparin, on the hepatic uptake of 3H-heparin was studied by liver perfusion experiments in rats. Fractionated 3H-heparin concentration in the recirculated perfusate decline one-exponentially with time for each of six initial concentration levels of alpha-globulin. The hepatic uptake clearance of fractionated 3H-heparin was 0.154 ml/min/g liver in the absence of alpha-globulin, and it decreased with increasing alpha-globulin concentrations. This result indicates that the hepatic uptake rate of alpha-globulin-bound fractionated 3H-heparin is lower than that of unbound fractionated 3H-heparin. On the other hand, it was indicated that almost all fractionated 3H-heparin binds to alpha-globulin at 8 mg/ml of alpha-globulin in in vitro study. However, the hepatic uptake clearance of the heparin at the concentration was of a certain value that could not be ignored. It was suggested that alpha-globulin-bound fractionated 3H-heparin also contributed to the hepatic uptake of fractionated 3H-heparin. Therefore, a protein-mediated transport system, which has been reported for some low molecular weight drugs, may also exist in the hepatic uptake of such a high molecular weight compound as fractionated 3H-heparin.

Alpha-Globulins↗
PubMed1990

[Basic and clinical evaluation of rapid diagnosis of tuberculosis by detecting tuberculostearic acid].

Tuberculostearic acid (TSA) is known to be one of the characteristic lipid in the limited species of the order Actinomycetale, including Mycobacterium tuberculosis. We studied the significance of detecting TSA in the diagnosis of tuberculosis from clinical specimens collected from 791 patients with various respiratory diseases by using gas--chromatography/mass--spectrometry. By our method, the detectable limit of TSA was around 10(2)-10(3) bacilli of Mycobacterium tuberculosis, and our method is as sensitive as culture examination for tuberculosis. In sputa collected from patients with active pulmonary tuberculosis (n=169), TSA positively was around 90%, while less than 10% false positive ws also recognized. In pleural effusion (n=81) and bronchial washing (n=91) collected from patients with active tuberculosis, the positivity of TSA was around 70%. We could also detect TSA in about 30% of clinical specimens collected from patients suspected of tuberculosis. The diagnostic sensitivity of TSA for tuberculosis was similar to that of adenosine deaminase activity (ADA), while TSA was slightly superior to ADA in specificity. These findings indicate that detection of TSA from clinical specimens is useful to make rapid diagnosis of pulmonary tuberculosis.

Bronchoalveolar Lavage Fluid↗
PubMed1988

Immunodeficiency in preclinical smoldering adult T-cell leukemia.

We treated two Japanese patients with Pneumocystis carinii pneumonia. Inclusion bodies in both adrenal glands of patient no. 1 indicated a herpesvirus infection. The patient no. 2 recovered from the pneumonia upon sulfametoxazole-trimethoprim medication and high-dose methylprednisolone therapy. In both patients, anti-human T-cell leukemia virus type I (HTLV-I) antibodies were positive and anti-human immunodeficiency virus antibodies were negative. Peripheral leukocytes in patient no. 1 numbered 13.6 X 10(3)/microliter with 25% morphologically normal lymphocytes and 4% abnormal. Lymphocyte surface markers were 72.6%, CD4+, 13.6% CD8+ and 46.4% CD3+. In patient no. 2, leukocytes numbered 13.8 X 10(3)/microliter, including 18% lymphocytes, although no morphologically abnormal lymphocyte was evident. Lymphocyte markers were 36.6% CD4+, 16.8% CD8+ and 46.6% CD3+. Monoclonal integration HTLV-I proviral DNA in lymphocytes of patient no. 2 was demonstrated by Southern blotting. Thus, both patients must have had smoldering adult T-cell leukemia (ATL) without any cutaneous involvement, whereas the morphological diagnosis from peripheral blood smears was one of HTLV-I carrier status with a few atypical lymphocytes, i.e., the preclinical state of smoldering ATL. Pneumocystis carinii infections, a viral infection of the adrenals (no. 1), negative purified protein derivatives of the tuberculin reaction and suppressed blastogenesis of the peripheral lymphocytes indicated HTLV-I-induced impairment of the immune mechanism to have already occurred in both patients without there being a vast proliferation of ATL cells.

Adult↗
PubMedDate not supplied

Measurement of tuberculostearic acid in sputa, pleural effusions, and bronchial washings. A clinical evaluation for diagnosis of pulmonary tuberculosis.

Gas chromatography/mass spectrometry combined with selected ion monitoring was used to measure tuberculostearic acid (TSA), in sputum, pleural effusion, and bronchial washing. The detection limit corresponded to the amount of TSA eluted from as low as 10(3) tubercle bacilli. Sputa were collected from 169 patients with active pulmonary tuberculosis, 35 clinically suspected to be active, 53 with obsolete pulmonary tuberculosis, and 160 with pulmonary diseases other than tuberculosis. TSA was positive in 90% of the patients with active pulmonary tuberculosis (152/169) and 71% of the clinically suspected cases (25/35), respectively. In contrast, less than 10% of the patients with obsolete tuberculosis or other pulmonary diseases had a positive TSA. Pleural effusions and bronchial washings were also collected from patients with active tuberculosis and from those with other diseases, as the controls. TSA in pleural effusions and bronchial washings was detected in 24 of 32 patients and 15 of 22 patients with active tuberculosis, respectively. In those with pulmonary diseases other than tuberculosis, only 8.7% of pleural effusion (4/46) and 4.3% of bronchial washing samples (3/69) showed a positive TSA. Therefore, the measurement of TSA is useful as a rapid and sensitive method for diagnosing pulmonary tuberculosis.

Bronchoalveolar Lavage Fluid↗