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H Tsukada

Publications and source records attributed to H Tsukada.

At least 181 records · Page 10Linked to original sources
PubMed1993

Membrane damage and interleukin-1 production in murine macrophages exposed to listeriolysin O.

To obtain some insight into the interaction between listeriolysin O (LLO) and the macrophage membrane, we examined the effect of purified Listeria monocytogenes hemolysin on the viability and functions of mouse peritoneal exudate macrophages. The study showed that purified LLO impaired a variety of functions of the macrophages. First, it suppressed the luminol-dependent chemiluminescence response of macrophages. Second, it suppressed the phagocytic ingestion of opsonized sheep erythrocytes and latex beads. Third, exposure of macrophages to LLO resulted in an increase in dead cells, as determined by the trypan blue dye exclusion method. An interesting observation of this study is that the LLO-induced production of interleukin-1 from macrophages could not be blocked by preincubation with cholesterol, while the membrane-damaging ability could be blocked by cholesterol. The dissociation of the blocking effects of cholesterol suggests that the interleukin-1-inducing ability of LLO may be distinct from its membrane-damaging ability.

Animals↗
PubMed1993

Soluble complex of complement increases hydraulic conductivity in single microvessels of rat lung.

We determined the effect of sera enriched with the soluble complex of complement (SC5b-9), on hydraulic conductivity (Lp) of single pulmonary venules (diameter 20-30 microns). Sera free of anticoagulants and blood cells were prepared from rat and human blood. Lp were determined by our split drop technique in isolated, blood-perfused lungs prepared from anesthetized rats (2% halothane; Sprague Dawley, 500 g; n = 73). Zymosan-activated (ZAS) and control sera were used for Lp determinations. In ZAS prepared from human serum, SC5b-9 concentration was > 300 micrograms/ml (control: < 1 microgram/ml) as determined by ELISA. At baseline, Lp averaged 3.4 +/- .4 x 10(-7) ml/(cm2.s.cm H2O), but it increased by 217 +/- 32% with undiluted ZAS (P < 0.05). The Lp increase correlated significantly with different ZAS dilutions for rat serum and with SC5b-9 concentration for human serum. Lp did not increase significantly with ZAS prepared from heat-treated sera, C6- and C8-deficient sera; or with ZAS in which SC5b-9 had been depleted by immunoprecipitation. The ZAS-induced increase of Lp was blocked completely by venular preinfusion with the arginine-glycine-aspartic acid (RGD) tripeptide (1 mg/ml, 10 min). We report for the first time that: (a) SC5b-9 increases lung endothelial Lp; and (b) the increase of Lp is attributable to an integrin-dependent mechanism.

Animals↗
PubMed1993

[Serum level of Pseudomonas aeruginosa-specific IgA in patients with chronic lower respiratory tract infection and its clinical significance].

Elevation of the serum IgA level has been observed in many cases of chronic lower respiratory tract infection. To determine the specificity of elevated serum IgA for the pathogen colonizing the respiratory tract of patients, we measured Pseudomonas aeruginosa-specific IgA titers in patients with chronic lower respiratory tract infections by ELISA. Sonicated P. aeruginosa strain BB5746 was used as the coating antigen. Optical density was significantly elevated in sera from patients in whom P. aeruginosa was consistently isolated from sputum cultures, when they were respondent to the antigen, indicating that bacteria-specific IgA is not localized in the respiratory tract surface, but is circulating in the blood stream of these patients. The other two groups, chronic bronchitis patients from whom bacteria other than P. aeruginosa were occasionally isolated from sputum culture, and IgA nephropathy patients, had no detectable specific IgA in their sera as is the case in normal adults. Our results indicate that bacteria-specific serum IgA levels appeared to correlate with duration from the time of bacterial colonization with P. aeruginosa and the degree of bronchial and alveolar destruction seen on chest X-rays. In addition, detection of increased serum P. aeruginosa-specific IgA seems to contribute to the recognition of persistent bacterial colonization of the respiratory tract.

Adult↗
PubMed1992

IFN-gamma-producing ability as a possible marker for the protective T cells against Mycobacterium bovis BCG in mice.

We searched for a functional marker with which T cells mediating acquired cellular resistance (ACR) can be discriminated from those mediating delayed-type hypersensitivity (DTH) in mice immunized with Mycobacterium bovis BCG. Four wk after injection of the mice with 10(5) viable BCG (vBCG) cells emulsified in IFA, a passive transfer experiment revealed that T cells mediating DTH as well as ACR, which we designated TACR, were generated in the spleen. In contrast, T cells mediating only DTH (TDTH) were generated by immunization with 10(7) killed BCG cells along with IFA. The transferring ability of both TACR and TDTH was substantially reduced by treatment with anti-Thy-1.2 or anti-CD4 mAb plus complement, whereas anti-CD8 treatment had no effect. To determine the functional differences between TACR and TDTH, we assessed IL-2 and IFN-gamma production from TACR and TDTH after stimulation with PPD in vitro. Similar levels of enhanced IL-2 activity were detected in the culture supernatants of both groups of T cells. However, augmented production of IFN-gamma was observed only in TACR. This finding was confirmed by Northern blot analysis for detection of IFN-gamma-specific mRNA. In addition, a significant increase in the number of IFN-gamma-producing cells was observed only in T cells from mice immunized with vBCG. The production of IFN-gamma was also totally abolished by treatment with anti-Thy-1.2 and anti-CD4 mAb plus complement in vitro, whereas anti-CD8 mAb treatment had no effect. These results suggest that CD4+ protective T cells generated by immunization with vBCG are characterized by the ability to produce IFN-gamma after stimulation with specific Ag.

Animals↗
PubMed1992

Induction of macrophage interleukin-1 production by Listeria monocytogenes hemolysin.

Listeriolysin O produced by a hemolytic strain of Listeria monocytogenes was purified from the ammonium sulfate precipitate of a culture supernatant through the steps of ion-exchange chromatography and gel filtration. The purified hemolysin finally gave a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with a molecular weight of 58,000. When peritoneal exudate macrophages were stimulated with purified hemolysin, we found a high level of IL-1 activity as determined by thymocyte costimulator assay in the culture supernatant. Cell-associated and intracellular IL-1 activity was also detected. The activity in the supernatant or membrane was blocked by polyclonal antibody to murine IL-1 alpha. Moreover, IL-1-specific mRNA expression could be detected in the macrophages stimulated with listeriolysin O by Northern blot analysis. Possible contamination by LPS of the listeriolysin O preparation did not seem to contribute to the induction of macrophage IL-1 production.

Animals↗
PubMed1992

A case of ectopic opening of vasa deferentia into müllerian duct cyst.

We report very rare case in which the vasa deferentia entered a large Müllerian duct cyst in a 4-month-old infant. The presenting findings were lower abdominal mass and the complaint of urinary retention. A computed tomography scan of the pelvis showed a monolocular cystic mass between the bladder and the rectum. Surgical removal of the cyst was done because the mass increased in size and both hydronephroses and hydroureters were getting worse despite the use of antibiotics. The patient has no urological difficulty after the operation. This case was characterized as follows: the cyst was located on the midline, the vasa entered the cyst directly, the size of the cyst was large, and it was not associated with other malformations of the genitourinary system.

Choristoma↗
PubMed1992

[A clinical study of bacteremia in the last fifteen years].

Between 1976 and 1990, 208 cases of bacteremia in our department were studied. Community acquired bacteremias were only 18 (8.7%) cases. Bacteremias, particularly caused by Gram positive organisms, increased significantly after 1981, compared with the first five years. It was related to the marked increase in cases of venous access devices and less sensitivity of the Gram positive organisms to the new cephem antibiotics. In the study, 144 (69.2%) cases were eradicated. Severe underlying diseases or complication of pneumonia influenced the eradication rate of bacteremia. Bacteremia caused by methicillin resistant Staphylococcus aureus or Pseudomonas aeruginosa showed poor prognosis. The average duration from onset to death, was 5.1 days. Forty cases (62.5%) died within 3 days. Among the 201 cases, leukocytosis (WBC greater than 10,000/mm3) was present in 38.3%, while leukopenia (WBC less than 1000/mm3) in 25.3%. Eradication rate between the two groups was not significant. CRP was elevated (greater than 8.5 mg/dl) in 63.5%. The prognosis of this group was significantly poor. Elevation of serum bilirubin was also related with increase of mortality. According to these results, empiric therapy before the isolation of organisms is the most important strategy for treatment of bacteremia.

Adolescent↗
PubMed1992

Effects of endothelin-1 and conversion of big endothelin-1 in the isolated perfused rabbit lung.

We examined the effects of endothelin-1 (ET-1) on pulmonary hemodynamic and transvascular fluid filtration and the conversion of big endothelin-1 (big ET-1), a precursor of ET-1, in isolated perfused rabbit lungs at constant vascular and airway pressures. Furthermore we examined whether ET-1 contributes to cyclooxygenase metabolism. The perfusate flow decreased significantly after bolus administration of 1 or 0.1 nmol of ET-1. Lung weight did not increase throughout the experimental period. Big ET-1- (1 nmol) induced decrease in the flow was slow in developing, although the maximum response was comparable to that induced by the same dose of ET-1. The concentration of bit ET-1 in the perfusate progressively decreased, while that of ET-1 increased in a time-dependent manner. Phosphoramidon, an inhibitor of metalloproteinase, suppressed the pressor effect of big ET-1 (P less than 0.01) and the increase in the concentration of ET-1 in the perfusate (P less than 0.05). The present findings provide the first evidence suggesting that the potent vasocontractile effect of big ET-1 in pulmonary circulation can be attributed to the production of ET-1 by the conversion from big ET-1 in the vascular bed. ET-1-induced perfusate flow changes were not affected by indomethacin, and the concentration of 6-ketoprostaglandin F1 alpha, a metabolite of prostacyclin, did not increase after ET-1 administration.

Animals↗
PubMed1992

Interferon gamma attenuates hypertensive renal injury in salt-sensitive Dahl rats.

Evidence has been provided that the immunological mechanism is involved in the genesis or maintenance of hypertension. In the present study, we investigated the effects of interferon gamma, a potent immunomodulator derived from lymphocytes, on hypertension and organ damage in Dahl salt-sensitive rats and in spontaneously hypertensive rats. Subcutaneous injection of interferon gamma (5 x 10(4) units/kg body wt once a week for 10 weeks) reduced blood pressure in Dahl salt-sensitive rats fed a 4% high salt diet (174 versus 194 mm Hg, p less than 0.025). This blood pressure reduction was associated with an improvement of renal functions, an increase in glomerular filtration rate (690 versus 569 ml/day/100 g body wt, p less than 0.05), and decreases in urinary protein excretion (48 versus 78 mg/day/100 g body wt, p less than 0.025) and urinary N-acetyl-beta-D-glucosaminidase excretion (143 versus 183 milliunits/day/100 g body wt, p less than 0.05). Morphological investigation showed a marked resolution of the vascular injuries seen in untreated Dahl salt-sensitive rats, e.g., intimal and medial hyperplasia, with infiltration of inflammatory cells, and significant amelioration of the glomerular sclerotic changes. In contrast, interferon gamma affected neither blood pressure nor renal functions in spontaneously hypertensive rats. These data indicate that interferon gamma ameliorates the development of hypertension and vascular and renal injuries in Dahl salt-sensitive rats. The resolution of vascular and renal injuries contributes, in part, to the antihypertensive action of interferon gamma.

Acetylglucosaminidase↗
PubMed1992

[Respiratory control in diffuse interstitial lung disease].

Whether the change of lung volume affect ventilatory responsiveness to chemical stimuli has not been studied in patients with interstitial lung disease (ILD). We measured the responses of minute ventilation (VE), tidal volume (VT), and occlusion pressure (P0.1) to hypercapnia (HCVR) and hypoxia (HVR) in these patients. Breathing efficiency (delta VE/delta P0.1) and effective compliance (delta VT/delta P0.1) were also measured under the same stimuli. 1) HCVR and HVR were measured in one female patient with hypersensitivity pneumonitis. VE responses during low VC phase (VC; 71% of predicted value) were similar to that during increased VC phase (VC; normal level) in both HCVR and HVR. However, VT responses of low VC phase were lower than those of increased phase, and P0.1 responses of low VC phase were higher than those of increased VC phase. Both breathing efficiency and effective compliance of low VC phase were lower than those of increased VC phase. 2) Thirty one patients with ILD were divided into two groups: low VC group; VC < 80% of predicted value, and normal VC group; VC > 80% of predicted value. HCVR and HVR were compared between two groups. Mean values of VE response to hypercapnia and hypoxia in low VC group were lower than those of in normal group, although they were not significantly different. VT response to hypercapnia and hypoxia were significantly lower of low VC group than those of normal VC group. Mean values of P0.1 responses to hypercapnia and hypoxia of low VC group were higher than those of normal VC group, although they were not significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Imprint cytodiagnosis of lymph node metastasis in resected lung cancer].

The cytological examination of lymph node imprints is a rapid and useful method for diagnosis of lymph node metastasis. We applied this technique for the diagnosis of regional lymph node metastasis of resected lung cancer, and compared its diagnostic value with histological examination. The accuracy rate of imprint cytology is 97.3%, and the sensitivity rate is 100%. We conclude that imprint cytology of lymph node for diagnosis of cancer metastasis is highly accurate and simple, and its diagnostic value may be equal to that of routine histological examination.

Adenocarcinoma↗
PubMed1992

[A case of acute renal failure in a patient with idiopathic hypouricemia].

This report is a 17-year-old man with an acute renal failure who complained of nausea, vomiting, bilateral loin pain and abdominal pain after scuffle. Renal biopsy specimen obtained from the left kidney revealed acute tubular necrosis. After recovering renal function he showed extreme hypouricemia (serum uric acid, 0.6 mg/dl) and elevated uric acid clearance (62-78 ml/min). The fractional excretion of uric acid (CUA/Ccr) could not be influenced by either oral pyrazinamide or probenecid. As no other renal tubular or metabolic abnormalities were detected, it is suggested that presecretory reabsorption defect or subtotal defect in uric acid transportation was responsible for the hypouricemia in this patient.

Acute Kidney Injury↗
PubMed1991

Reserpine-induced reduction of in vivo binding of SCH 23390 and N-methylspiperone and its reversal by d-amphetamine.

In order to clarify the role of endogenous dopamine in the binding of [3H]SCH23390 and [3H]N-methylspiperone to the mouse striatum in vivo, the effects of reserpine and the reversal of these effects by d-amphetamine were investigated. Radioactivity was measured in the striatum and cerebellum following i.v. injection of each ligand into control and drug-treated mice. The ratio of radioactivity in the striatum to that in the cerebellum, plotted as a function of time, showed a linear correlation. Pretreatment with reserpine 24 h prior to injection of tracer significantly decreased the in vivo binding of both [3H]SCH23390 and [3H]N-methyl-spiperone in a dose-dependent manner. Saturation experiments indicated that these changes in in vivo binding were due mainly to changes in apparent affinity rather than to the number of binding sites available. Administration of d-amphetamine to reserpine-treated mice reversed the effect of reserpine in a dose-dependent manner. Blockade of dopamine D1 receptors with SCH23390 did not prevent the reversal by d-amphetamine of [3H]N-methylspiperone binding in vivo; however, treatment with haloperidol did prevent the effect of d-amphetamine on [3H]SCH23390 binding. These results suggest that dopamine D2 receptor-mediated neurotransmission might itself regulate the binding of dopamine to receptors in vivo.

Animals↗
PubMed1991

Difference in in vivo receptor binding between [3H]N-methylspiperone and [3H]raclopride in reserpine-treated mouse brain.

The in vivo binding of [3H]N-methylspiperone (NMSP) and [3H]raclopride was compared in mice treated with reserpine (5 mg/kg, 24 hr prior to the tracer injection). With both radioligands, selective accumulation of radioactivity in the striatum following intravenous injection was observed, whereas a relatively low accumulation and a rapid decline in radioactivity in the cerebellum was seen. Reserpine significantly decreased [3H]NMSP binding in vivo, however it increased [3H]raclopride binding. By compartment model analysis, it was found that the decrease in [3H]NMSP binding was primarily due to the decrease in the association rate (K3) and the increase in [3H]raclopride was due to the decrease in the dissociation rate (K4) in vivo. As both Kd and Bmax of dopamine D2 receptors have been reported to be unaltered by reserpine, these results suggested that some unknown factors except Kd and Bmax which influence on in vivo binding of receptors might be changed by reserpine. These results revealed that it is of importance to measure kinetics of ligand-receptor binding in vivo rather than static analysis. These two different types of radioligands can be combined to reveal functional roles of dopamine receptor in vivo, especially in the study of the human brain with positron emission tomography (PET).

Animals↗
PubMed1991

Swim stress alters in vivo binding of [3H]N-methylspiperone.

The effect of swim stress on the in vivo binding of [3H]N-methylspiperone in the striatum of the mouse was investigated. Mice were forced to swim for 5 min at 18 degrees C and the time course of radioactivity in the striatum and cerebellum, following intravenous injection of [3H]N-methylspiperone was measured. The ratio of radioactivity in the striatum to that in the cerebellum was plotted as a function of time for the estimation of in vivo binding to dopamine D2 receptors. Immediately after the swim stress, a significant decrease in binding to D2 receptors in vivo was observed. Neither the KD nor Bmax determined by in vitro binding were altered by swim stress. The time course of the changes in binding, within a 24 hr period, following the swim stress was also studied and a rapid reversal of binding, within 1 hr after the swim stress was observed. In vivo binding of [3H]N-methylspiperone in the cerebral cortex, which appeared to involve serotonin receptors, as well as D2 receptors, was not significantly altered by the swim stress. A saturation study of in vivo binding indicated that the decreases in binding to D2 receptors, due to swim stress, were primarily caused by changes in the apparent affinity rather than in the number of binding sites available in vivo. These results support the hypothesis that micro-environmental factors, including the diffusion barrier to the synapse, might be altered by swim stress.

Animals↗