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H Kumamoto

Publications and source records attributed to H Kumamoto.

48 records · Page 3Linked to original sources
PubMed1998

Angiotensin II type 1 receptor gene polymorphisms in patients with cardiac hypertrophy.

Chronic mechanical stress of the heart secondary to arterial hypertension is a primary cause of left ventricular hypertrophy (LVH). The renin-angiotensin system (RAS) plays an important role in the cardiovascular system, regulating the expression of cardiac hypertrophy, in part, independent of the effects of systemic hypertension. A major component of RAS is angiotensin converting enzyme (ACE), which is upregulated in pressure overload-induced cardiac hypertrophy as well as heart failure. In a recent study, we found that the T allele of the M235T polymorphism of the angiotensinogen gene in sporadic hypertrophic cardiomyopathy (HCM) patients is associated with LVH. The present study was designed to assess the contribution of the polymorphisms of the angiotensin II type 1 receptor (AGT1R A1166C) genes on development of left ventricular hypertrophy. Patients with hypertensive LVH and relatives of HCM without manifesting the disease, showed higher C allele frequency compared to patients with HCM (11.3% vs 4.2%, chi 2 = 5.3, p < 0.05 and 10.5% vs 4.2%, chi 2 = 5.3, p < 0.05, respectively), but healthy controls did not (11.3% vs 7.5%, chi 2 = 1.42, NS and 10.5% vs 7.5%, chi 2 = 1.2, NS). The strong interaction between ACE I/D and AGT1R A1166C gene polymorphisms has been found in groups of relatives of HCM patients; odds ratio associated with ACE D allele was significant in subjects carrying the AGT1R C allele (OR = 7.3, 95% CI 1.6-33.1; chi 2 = 7.9, p < 0.02) compared with healthy subjects. We conclude that the molecular variant of the AGT1R A1166C gene is not contributing to the development of cardiac hypertrophy in hypertensive LVH and HCM patients, whereas carriers of both C and D alleles had a four-fold increase in the odds ratio for family history of HCM without manifesting the disease.

Aged↗
PubMed1997

Detection of apoptosis-related factors and apoptotic cells in ameloblastomas: analysis by immunohistochemistry and an in situ DNA nick end-labelling method.

To clarify the possible role of apoptosis in odontogenic epithelium, apoptosis-related factors and apoptotic cells were examined by immunohistochemistry and an in situ DNA nick end-labelling method. Expression of bcl-2 protein was detected in both normal and neoplastic odontogenic epithelium, whereas expression of p53 protein was detected only in neoplastic but not in normal odontogenic epithelium. The prevalence of cases positive for Lewis(y) antigen in ameloblastomas was significantly lower than in enamel organs. Correlation between these factors and apoptotic cells presented by an in situ DNA nick end-labelling method was not clear. The number of apoptotic cells in ameloblastomas was significantly greater than in normal odontogenic epithelium, and apoptotic reactions in the granular cell type ameloblastoma tended to be more frequently detected than in other types of ameloblastomas. These results suggested that apoptotic cell death might play an important role in oncogenesis and/or tissue differentiation in odontogenic epithelium.

Ameloblastoma↗
PubMed1996

Characterization of novel monoclonal antibodies raised against formalin-fixed, paraffin-embedded human ameloblastoma.

To obtain monoclonal antibodies reactive with odontogenic but not other types of epithelium, mice were immunized with homogenates of fixed ameloblastoma tissues, and monoclonal antibodies Y4 and M11 were produced. Y4 reacted immunohistochemically with odontogenic epithelial components but not with those of squamous differentiation, while M11 reacted with odontogenic epithelial components and a part of keratotic epithelial tissues. Immunoglobulin isotypes of both antibodies were IgM as determined by Ouchterlony immunodiffusion and enzyme-linked immunosorbent assays. Western blotting revealed that the antigen recognized by Y4 had a molecular mass of approximately 66 kDa; however, the antigen reactive with M11 was not identified by Western blotting in spite of various attempts in changing reaction conditions. These antibodies may be beneficial to histological analyses of odontogenic tissues and their related lesions.

Ameloblastoma↗
PubMed1996

Transfusion-associated graft-versus-host disease diagnosed by polymerase chain reaction analysis of DNA microsatellites: an autopsy case with immunohistochemical investigation.

An autopsy case of transfusion-associated graft-versus-host disease (TA-GVHD) is reported with immunohistochemical investigation and polymerase chain reaction (PCR) analysis. In a 58-year-old male, esophagectomy for carcinoma was performed with a transfusion of 4 units of fresh whole blood. Diarrhea, fever, erythematous rash, pain and leukopenia occurred with an onset 11 days after the operation. He died of sudden dyspnea 29 days after the operation. At autopsy, histological examinations revealed lichenoid lesion in the skin, injury of mucosal epithelia in the digestive tract and damage of interlobular bile ducts in the liver. Immunohistochemical investigation suggested the association between these lesions and CD8-positive T lymphocytes. Severe disturbances of bone marrow and lymphoid organs were accompanied with gram-positive cocci infection in the lungs, esophagus and small intestine. PCR analysis of DNA at microsatellite loci, human growth hormone (HGH) and apolipoprotein B (Apo B), showed DNA chimerism and established the definitive diagnosis of TA-GVHD.

Antigens, CD↗
PubMed1992

[A case of vasovagal syncope associated with venipuncture].

A 33 year-old-man presented recurrent syncopal episodes after venipuncture. This was sometimes associated with seizure. It was also noted that the syncope was aroused by mental stress. The patient was admitted to the department of neurological medicine because of epilepsy. Cardiac arrest of more than 15 seconds was detected during the venipuncture-prooshed syncope test. He had normal routine testing, holter monitoring, head CT scan, carotid sinus massage, valsalva maneuver etc. The syncope was similar to a malignant vasovagal one which has no typical warning signs. He had recurrent syncopal episodes without typical prodrome. Therefore a DDD pacemaker was implanted. It has not been completely established as effective in the treatment of vasovagal syncope, but for the treatment of syncope involving cardioinhibitory action, dual chamber pacing in considered as the main treatment available.

Adult↗