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H Hanawa

Publications and source records attributed to H Hanawa.

70 records · Page 4Linked to original sources
PubMed1993

FK506 therapy of experimental autoimmune myocarditis after onset of the disease.

Preventive effects of FK506 on autoimmune myocarditis have been demonstrated, but the therapeutic efficacy of the agent in established myocarditis yet remains to be assessed. In this study, effects of FK506 on experimental autoimmune myocarditis were investigated by the use of the agent after the onset of the disease. Lewis rats were immunized with either cardiac myosin or bovine serum albumin (BSA) in complete Freund's adjuvant. The onset of the disease was ascertained by examining randomly chosen cardiac myosin-immunized rats. Animals were divided into four groups: the BSA-immunized saline-treated group (group A, n = 6); the BSA-immunized FK506-treated group (group B, n = 6); the myosin-immunized saline-treated group (group C, n = 6); and the myosin-immunized FK506-treated group (group D, n = 11). Saline or 1.0 mg/kg/day of FK506 were intramuscularly injected from day 16 to day 27. All the rats were put to death on day 28. Rats of group C became severely ill by the third week, while in contrast, rats of group D remained active, as did rats of groups A and B. The heart weight/body weight ratio was significantly lower in group D than in group C rats. Group mean values were 3.48 +/- 0.10 gm/kg for group A, 3.48 +/- 0.16 gm/kg for group B, 4.94 +/- 0.66 gm/kg for group C, and 3.88 +/- 0.43 gm/kg for group D. Rats of group C showed severe myocarditis with mononuclear cell infiltration, myocardial necrosis, and interstitial edema.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Effects of cyclosporine, prednisolone and aspirin on rat autoimmune giant cell myocarditis.

OBJECTIVES: Preventive effects of cyclosporine, prednisolone and aspirin on autoimmune giant cell myocarditis in rats were investigated. BACKGROUND: The therapeutic efficacy of immunosuppressants for human myocarditis is controversial. Although harmful effects of immunosuppressive therapy on experimental viral myocarditis have been reported, the effects on autoimmune myocarditis have not been investigated. Recently, a novel experimental autoimmune myocarditis model characterized by congestive heart failure and multinucleated giant cell has been established. Using this model, the preventive effects of cyclosporine, prednisolone and aspirin on autoimmune myocarditis were investigated. METHODS: Lewis rats were immunized with cardiac myosin in complete Freund's adjuvant on days 0 and 7. In experiment 1, four groups of seven rats each were established. Rats in each group received for 21 days intraperitoneal injections of either 1) phosphate-buffered saline solution, 1 ml/day (control); 2) cyclosporine, 20 mg/kg body weight per day (cyclosporine 20); 3) prednisolone, 4 mg/kg per day; or 4) aspirin, 15 mg/kg per day. In experiment 2, two additional groups (five rats each) received for 21 days an injection of cyclosporine, 1 or 5 mg/kg per day (cyclosporine 1 and cyclosporine 5, respectively). All rats were killed on day 21, when histopathologic studies were performed and the titers of antimyosin antibodies were measured. RESULTS: The rats in the control, prednisolone and aspirin groups became ill and immobile in week 3. In comparison, rats in the cyclosporine 5 and 20 groups were still active until death was induced. Heart weight/body weight, lung weight/body weight and liver weight/body weight ratios in the rats in the cyclosporine 5 and cyclosporine 20 groups were significantly lower than those in the control group, and no differences were detectable among rats in the control, prednisolone and aspirin groups. The rats in the latter three groups and the cyclosporine 1 groups showed severe myocarditis with multinucleated giant cells. However, myocarditis was effectively prevented in the rats in the cyclosporine 5 and 20 groups. The histologic scores in each group were 2.91 in the control group, 2.14 in the prednisolone group, 2.91 in the aspirin group and 0.02, 2.58 and 0.07, respectively, in the cyclosporine 20, 1 and 5 groups. Production of antimyosin antibodies was remarkably suppressed in rats in the cyclosporine 5 and 20 groups in comparison with values in all other groups. CONCLUSIONS: Autoimmune myocarditis is preventable by cyclosporine but not by prednisolone or aspirin in usual dosages.

Animals↗
PubMed1993

In situ inactivation of infiltrating T cells in the central nervous system with autoimmune encephalomyelitis. The role of astrocytes.

Our previous study using bromodeoxyuridine (BrdU) has shown that T cells in lesions of experimental autoimmune encephalomyelitis (EAE) in the rat central nervous system (CNS) lose their proliferating capability immediately after infiltration into the CNS. To characterize the nature of this phenomenon in more detail, we have isolated T cells from EAE lesions and examined their surface phenotype and response to encephalitogenic antigen, myelin basic protein (MBP). By flow cytometry (FCM) analysis, it was revealed that compared with peripheral blood lymphocytes, up-regulation of interleukin-2 (IL-2) receptors (0.06%-->3.73%) and the lymphocyte function-associated antigen-1 (LFA-1) molecules (0.76%-->17.6%) on spinal cord T cells (SCT) was observed. In spite of the latter finding suggesting that SCT are activated, SCT recovered from rats with full-blown EAE responded very poorly to MBP. The addition of thymocytes or thymocytes plus astrocytes did not alter the low responsiveness of SCT. More importantly, astrocytes strongly suppressed the response of lymph node T cells to MBP. Using MBP-specific T-line cells, it was revealed that T-cell suppression might be induced by incomplete presentation of MBP and release of suppressive humoral factors by astrocytes. Since the response of SCT was still poor when assayed after three and 12 rounds of stimulation with the antigen and propagation with IL-2, this phenomenon is long lasting. These findings are consistent with the findings obtained by the BrdU study that infiltrating T cells into the CNS do not proliferate vigorously. Taken together, the poor response of infiltrating T cells to MBP would be induced by co-existing cells such as astrocytes although the T cells are in an active form as judged by their surface phenotype. The present study suggests that activation of non-haematopoietic parenchymal cells in each organ by infiltrating T cells and subsequent inactivation of the T cells are important healing processes for organ-specific autoimmune diseases.

Animals↗
PubMed1992

An immunosuppressant compound, FK-506, prevents the progression of autoimmune myocarditis in rats.

A new immunosuppressive compound, FK-506, is a macrolide produced by Streptomyces tsukubaensis. It is reported that FK-506 prolongs the viability of allogenic grafts of the heart and kidney in vivo and inhibits the development of autoimmune diseases. Furthermore, immunosuppressive therapy of myocarditis in humans has been given special attention by various observers; however, it is controversial. This study investigates the effects of FK-506 on experimental autoimmune myocarditis in rats. We performed two experiments. In Experiment 1, FK-506 was given intramuscularly on Days 11-20 after the first immunization. The rats were immunized twice (on Day 0 and Day 7). They were injected subcutaneously in the footpads with 1.0 mg of human cardiac myosin in equal volumes of complete Freund's adjuvant supplemented with Mycobacterium tuberculosis. They were divided into four groups: Control (six rats, saline), group 1 (six rats, FK-506: 0.1 mg/kg/day), group 2 (seven rats, FK-506: 0.32 mg/kg/day), and group 3 (six rats, FK-506: 1.0 mg/kg/day). To investigate the histologic extent of myocarditis, we formulated a histologic score (0-3). Histologic scores were: Control, 1.90 +/- 0.14; group 1, 0.97 +/- 0.46; group 2, 0.03 +/- 0.05; and group 3, 0 +/- 0. The indices of heart weight/body weight were: Control, 0.74 +/- 0.10%; group 1, 0.45 +/- 0.05%; group 2, 0.35 +/- 0.03%; and group 3, 0.35 +/- 0.03%. In Experiment 2, FK-506 was given on Days 1-10 after the first immunization, earlier than in Experiment 1. The rats were similarly divided into four groups. Each group was given the same dose of FK-506 as in Experiment 1. Histologic scores were: Control 1.49 +/- 0.24; group 1, 1.60 +/- 0.22; group 2, 0.29 +/- 0.41; and group 3, 0.03 +/- 0.03. The indices of heart weight/body weight were: Control, 0.69 +/- 0.15%; group 1, 0.76 +/- 0.09%; group 2, 0.42 +/- 0.08%; and group 3, 0.37 +/- 0.03%. Accordingly, in Experiments 1 and 2, the effects of FK-506 on autoimmune myocarditis were dose-dependent. On the other hand, in Experiments 1 and 2, not only in the control group but also in all treated groups, the titers of anti-myosin IgG were high. In conclusion, even if it is administered just before the onset of myocarditis, FK-506 is extremely effective at suppressing autoimmune myocarditis, despite a high titer of anti-myosin IgG.

Animals↗
PubMed1992

Immunohistochemical characterization of infiltrating mononuclear cells in the rat heart with experimental autoimmune giant cell myocarditis.

The pathogenesis of giant cell myocarditis remains unclear. Subsets of inflammatory infiltrating cells may reflect the pathogenesis and etiology of the disease. Therefore, we examined subsets of infiltrating mononuclear cells in the heart of the rat with experimental giant cell myocarditis. Lewis rats were immunized with cardiac myosin in Freund's complete adjuvant (FCA). Severe myocarditis characterized by congestive heart failure and multinucleated giant cells were elicited. The lesions were composed of predominant mononuclear cells, polymorphonuclear neutrophils and fragments of degenerated myocardial fibres. The subsets of infiltrating mononuclear cells were investigated using MoAbs against rat CD4+ T cell (W3/25), CD8+ T cell (CX8), B cell (OX33) and macrophage (OX42). By serial examination, bound immunoglobulin could only be found on degenerated myocardial fibres. In this model, most infiltrating mononuclear cells were composed of macrophages and CD4+ T cells. The frequencies of macrophages and CD4+ T cells were 73.7% and 13.8%, respectively. CD8+ T cells were scarce and B cells were rare in the lesions. The frequencies of CD8+ T cells and B cells were 4.5% and 0.4%, respectively. The dominance of macrophages and CD4+ T cells was the constant finding among the sites of the lesions and throughout the course of the disease. These characteristic subsets of infiltrating cells were in contrast to those of murine viral myocarditis which were mainly composed of natural killer (NK) cells and CD8+ T cells. Clarifying the subsets of infiltrating cells in myocarditis may contribute to differential diagnosis of myocarditis between viral and autoimmune types. From this study, the pathogenesis of experimental autoimmune giant cell myocarditis seemed to be closely related to CD4+ T cells and macrophages.

Animals↗
PubMed1992

Acute hemodynamics of pimobendan in chronic heart failure. A comparative crossover study of captopril and pimobendan.

Acute hemodynamics of pimobendan were compared to captopril in a crossover trial in patients with chronic heart failure (NYHA II-III). Heart failure had been stabilized by conventional therapy with diuretics and digitalis for more than 2 weeks. Patients receiving vasodilators were excluded. The hemodynamics were analyzed using a Swan-Ganz catheter at the bedside during drug administration. Following an intravenous injection of 2.5 mg of pimobendan, there was a significant increase in heart rate and decrease in mean pulmonary artery pressure, total pulmonary resistance, mean arterial pressure, systemic vascular resistance and mean right atrial pressure 2 hours after the injection. Captopril (12.5 mg, orally) significantly decreased mean arterial pressure, systemic vascular resistance and double product 2 hours after administration. In this study, the inotropic effect was evaluated through the relation between the stroke volume index and diastolic pulmonary artery pressure, and also between the stroke volume index and mean arterial pressure. Although decreases of diastolic pulmonary artery pressure and mean arterial pressure were seen with both drugs, the differences in stroke volume index were not significant. In comparison with captopril, the acute hemodynamics of pimobendan are characterized as follows: 1) the systemic arteriovasodilating effects of the two drugs were equal, 2) the pulmonary arteriovasodilating effect of pimobendan was marked, 3) a venodilating effect, documented through a decrease of mean right atrial pressure, was seen only with pimobendan. This study concluded that pimobendan is a stronger arterio-venodilator than captopril.

Aged↗
PubMed1992

Diastolic mitral regurgitation in intact mitral valve detected by color Doppler echocardiography in a patient with acute aortic regurgitation.

A 38-year-old man was admitted with coingestive heart failure due to infective endocarditis. Echocardiography with color Doppler imaging revealed severe aortic regurgitation, mitral valve premature closure and diastolic mitral regurgitation. The flow of the diastolic mitral regurgitation was directed to the posterior wall of the left atrium through just behind the posterior mitral leaflet. The diastolic mitral regurgitation was observed only in the period of late diastole and no mitral regurgitation could be detected in the systolic phase. After successful aortic valve replacement, the diastolic mitral regurgitation disappeared completely.

Adult↗
PubMed1992

[Acute hemodynamic effects of pimobendan and captopril: a comparative study in the same patients with chronic heart failure].

In this study, the acute hemodynamic effects of pimobendan (2.5 mg), a new drug, was compared with that of captopril (12.5 mg) in the same 8 patients with chronic heart failure (NYHA class II-III); 3 with dilated cardiomyopathy and 5 with regurgitant valvular heart disease. The hemodynamics were serially assessed before and after drug administration for at most 6 hours. Pimobendan reduced mean blood pressure, mean pulmonary artery pressure, pulmonary capillary wedge pressure, right atrial pressure, total systemic vascular resistance, and total pulmonary vascular resistance but it increased heart rate. By contrast, captopril reduced mean blood pressure and double product. No significant changes were noted in the cardiac index, stroke volume index, AV-O2 difference or the arterial oxygen pressure between the 2 drugs. In conclusion, pimobendan seems to function as a strong arterio-veno-dilator rather than as an inotropic agent in patients with chronic heart failure.

Aged↗
PubMed1991

Characteristics of giant cells and factors related to the formation of giant cells in myocarditis.

Giant cell myocarditis is a serious and frequently fatal inflammatory heart disease of which the etiology remains unknown. In the present study, we investigated the origin of multinucleated giant cells in myocarditis with the use of an experimental model. We also examined the factors relating to the formation of giant cells in myocarditis. Severe myocarditis characterized by the appearance of multinucleated giant cells was induced in Lewis rats by immunization with cardiac myosin in complete Freund's adjuvant. Two types of giant cells, foreign body giant cell-like and myocytelike, were observed in this myocarditis. Immunohistochemical studies revealed that both types of multinucleated giant cells were stained with OX42 and ED1 (macrophage markers) and were not stained with anti-desmin antibody and HHF35 (markers for muscle fibers). Therefore, it is likely that multinucleated giant cells in this myocarditis are derived from macrophages. During the course of the disease, the appearance of multinucleated giant cells was restricted to a period corresponding with the fulminant phase of inflammation. When the severity of the disease was modulated by immunization with various doses of the antigen, multinucleated giant cells appeared only in severe myocarditis after inoculation of a large dose of the antigen. Administration of immunoadjuvants also affected the formation of giant cells. Most of the rats injected with cardiac myosin in complete Freund's adjuvant developed giant cell myocarditis.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

[Variations of clinical rest position in complete denture-wearing subjects].

With a view to proposing concrete grounds for the measurement of the rest vertical dimension on the face in the establishment of the vertical dimension of occlusion for edentulous patients, 20 complete denture-wearing subjects were made to take a clinical rest position by 4 different denture-wearing patterns, i.e. setting both dentures (UL), setting maxillary denture only (U), setting mandibular denture only (L) and completely edentulously (O), and were measured for the distance between 2 points on the face by slide calipers masking the reading part. The data were statistically analyzed and the following results were obtained. 1) Rest vertical dimension was largest for L, and significant differences were noted between UL, O, U and L, but not between UL and O, between UL and U and between O and U. 2) No significant difference in rest vertical dimension was noted between subjects of not more than 65 years and those of not less than 65 years. 3) No significant difference in rest vertical dimension was noted between the group of subjects of not more than 6 edentulous years and that of subjects of not less than 6 edentulous years. 4) The above results give suggestions to the measurement and evaluation of the vertical dimension between 2 points on the face when jaws are in the vertical relationship with the clinical rest position, in the establishment of the vertical dimension of occlusion.

Age Factors↗
PubMed1985

Postnatal sudanophilic leukodystrophy in two siblings.

Reported here are two siblings with sudanophilic leukodystrophy occurring in early infancy. Soon after birth, high fever, distension of the abdomen and spasticity of the extremities were noted. Neurologic disorders, frequent convulsive seizures, and malnutrition caused both siblings to die at the age of 3 and 6 months, respectively. Neuropathologic examination of the brain revealed diffuse demyelination in the cerebral and cerebellar white matter as well as a disturbance of the myelination, especially in the descending pathway. Numerous sudanophilic lipids and glial fibers proliferated in the demyelinated areas. Neurochemically, there was a marked decrease in all lipid components, cholesterol, phospholipids, and glycolipids and an increase in cholesterol ester. Fatty-acid composition of cerebroside and sulfatide, especially that of long-chain acids, was within normal range, unlike the fatty-acid composition found in connatal Pelizaeus-Merzbacher disease. The brain damage in postnatal infant caused by frequent convulsive seizures and the severe demyelination in the cerebral and cerebellar white matter in both patients are discussed. The cases of sudanophilic leukodystrophy and Pelizaeus-Merzbacher disease occurring in children under 5 years of age are reviewed.

Brain↗
PubMed1980

[Clinical studies of effectiveness of ceftezole (Falomesin 'Chugai') on the infectious disease in infancy and childhood (author's transl)].

Clinical studies of the effectiveness of ceftezole (Falomesin 'Chugai') were performed on 50 cases of infants and children with infectious disease during November 1978 and February 1979. Effective results were obtained in 86% of subjects with remarkable effect especially in the group of acute upper respiratory disease. No side effect was detected in our study while elevated mean value of platelet count was observed after medication.

Age Factors↗
PubMedDate not supplied

High-level expression of naked DNA delivered to rat liver via tail vein injection.

BACKGROUND: High levels of foreign gene expression in mouse hepatocytes can be achieved by rapid tail vein injection of a large volume of a naked DNA solution, the 'hydrodynamics-based procedure'. Rats are more tolerant of the frequent phlebotomies required for monitoring blood parameters than mice, and thus are better for some biomedical research. METHODS: We tested this technique for the delivery of a therapeutic protein in normal rats, using a rat erythropoietin (Epo) expression plasmid vector, pCAGGS-Epo. RESULTS: We obtained maximal Epo expression when the DNA solution was injected in a volume of 25 ml (approximately 100 ml/kg body weight) within 15 s. We observed a dose-response relationship between serum Epo levels and the amount of injected DNA up to 800 microg. Using quantitative real-time PCR, the vector-derived Epo mRNA expression was mainly detected in the liver. When a lacZ expression plasmid was injected similarly, beta-galactosidase was exclusively detected in the liver, mainly in hepatocytes. Toxicity attributable to the technique was mild and transient, as assessed by histochemical analysis. Epo gene expression and erythropoiesis occurred with Epo gene transfer in a dose-dependent manner, and persisted for at least 12 weeks, the last time point examined. Repeated administration of the plasmid DNA also effectively led to erythropoiesis. CONCLUSIONS: These results demonstrate that gene transfer into the liver via rapid tail vein injection can easily be achieved in the rat, which is more than 10 times larger than the mouse, and has significant value for gene function analysis in rats.

Animals↗