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Biomedical subjects

M Sekiguchi

Publications and source records attributed to M Sekiguchi.

At least 397 records · Page 22Linked to original sources
PubMed1990

Doppler assessment of pulmonary hypertension induced by hypoxic breathing in subjects susceptible to high altitude pulmonary edema.

To verify the abnormal pulmonary vascular response implicated in the pathogenesis of high altitude pulmonary edema (HAPE), we examined the hemodynamic responses to hypoxia in HAPE-susceptible subjects (HAPE-S) by means of both right heart catheterization and pulsed Doppler echocardiography. The HAPE-S were seven men and one woman with a history of HAPE. Six healthy volunteers who had repeated experiences of mountain climbing without any history of altitude-related problems served as control subjects. The HAPE-S showed much greater increase in pulmonary vascular resistance (PVR) than did the control subjects, resulting in a much higher level of pulmonary arterial pressure (Ppa) under acute hypoxia both of 15% O2 and 10% O2. We then evaluated the usefulness of pulsed Doppler echocardiography in the prediction of pulmonary hypertension. Acceleration time (AcT) and right ventricular ejection time (RVET) were measured from the flow velocity pattern in the right ventricular outflow tract. The ratio of AcT to RVET was correlated to invasively determined mean Ppa (Ppa) and PVR. The results were as follows: (1) AcT/RVET = 0.52 to 0.0047 (Ppa), r = -0.93, SEE = 0.017, p less than 0.001 (HAPE-S); (2) AcT/RVET = 0.55 to 0.0055 (Ppa), r = -0.70, SEE = 0.030, p less than 0.001 (HAPE-S); (4) AcT/RVET = 0.52 to 0.00077 (PVR), r = -0.91, SEE = 0.016, p less than 0.001 (control subjects). We conclude that HAPE-S have a constitutional abnormality in the pulmonary vascular response to hypoxia, which is a possible causative factor of HAPE, and that pulsed Doppler echocardiography may be supportive to assess the pulmonary vascular pressor response in the HAPE-S.

Adult↗
PubMed1990

Computerized M-mode echocardiographic assessment of left ventricular diastolic function in patients with familial amyloid polyneuropathy.

To determine left ventricular diastolic properties in patients with familial amyloid polyneuropathy, 23 patients were studied by digitized M-mode echocardiography and were compared with 15 age-matched normal subjects. None of the patients had restrictive ventricular physiology and all but two showed normal left ventricular fractional shortening. Both the normalized peak rate of diastolic increase in left ventricular internal dimension and the normalized peak rate of diastolic thinning of posterior wall were significantly lower in patients than in normal subjects (2.0 +/- 0.8 vs 3.0 +/- 0.4 sec-1; p less than 0.001, and 2.5 +/- 1.2 vs 5.8 +/- 1.0 sec-1; p less than 0.001, respectively). The left ventricular isovolumic relaxation time in patients was 91.5 +/- 22.2 msec, compared with 64.0 +/- 2.6 msec in normal subjects (p less than 0.001). Of the 18 patients without clinical evidence of overt heart disease, 12 had normal ventricular wall thickness and normal fractional shortening, but 10 of the 12 exhibited some abnormalities in diastolic properties. In addition, indexes of diastolic function were significantly related to ventricular wall thickness alone. These findings indicate that left ventricular diastolic abnormalities precede the development of clinically overt heart disease, ventricular wall thickening, and systolic dysfunction and may be related to intramyocardial amyloid infiltration with resultant fibrosis in patients with familial amyloid polyneuropathy.

Adult↗
PubMed1990

Heterozygote effects in dreher mice.

The dreher mutation (gene symbol: dr) is an autosomal recessive mutation located on chromosome 1 of the mouse. Homozygous dreher mice (dr/dr) are ataxic, have a white belly spot, a short-tail, inner ear and skeletal malformations, and a variety of CNS abnormalities. Recently in our dreher colony (the drsst-J allele on a B6C3Fe background), we noticed mice with one or more white belly spots typical of drsst-J/drsst-J mice but which were non-ataxic and had a normal tail length; wild-type mice (+/+) of the same genetic background do not have simialr belly spots. Results of three breeding experiments indicate that a new mutation had not occurred, but rather that the spotted, non-ataxic mice are heterozygous dreher mice (drsst-J/+). Histological examination showed that drsst-J/+ mice have abnormalities in the hippocampal formation that are qualitatively similar to those found in drsst-J/drsst-J mice. Most frequently there is an increase in the number of pyramidal cells in CA3 and a marked thickening of the pyramidal cell layer. In contrast to dreher homozygotes the cerebellum appears to have a normal foliation pattern and no discernible laminar abnormalities. Thus, both breeding experiments and histological examination indicate that drsst-J is semidominant. We speculate that drsst-J is a "loss of function" mutation, but, in any event, the presence of phenotypic abnormalities in drsst-J/+ mice may be useful in identifying the primary developmental defect in dreher mice.

Animals↗
PubMed1990

[Elimination of mycoplasmas from cultured human cell lines utilizing a combination of two antibiotics, quinolone and a pleuromutilin derivative].

Forty three cultured human cell lines were treated with a combination of 2 antibiotics to eliminate contaminant mycoplasmas. One course of treatment was composed of consecutive 3 or 4 cycles. Each cycle grew cells in BM-1 (pleuromutilin derivative; Boehringer Mannheim) containing medium (10 micrograms BM-1/ml culture) for 3 days, alternating with MC-210 (quinolone; Dainihon Pharmaceutical) containing medium (0.625 micrograms MC-210/ml culture) for 4 days. No treatment failure was encountered with this procedure. Before treatments, 18 (90%) of 20 cell line samples were contaminated with mycoplasma, as tested by DNA hybridization method (MYCOPLASMA T.C. RAPID DETECTION SYSTEM; Gen-Probe Inc.). Out of 43 cell lines treated, 7 were reduced in growth and dropped out. Among the other 36 cell lines, 27 became negative, 5 borderline and 4 slightly positive to the mycoplasma detection. All of the latter 9 cell lines, treated with one more similar course, found to be free from mycoplasma. Six of the dropout lines were cured of mycoplasma by a second treatment, under modified culture conditions. The last cell line (NATO) was successfully treated with another lot of FCS. Thus, the procedure proved successful even in treating promiscuously infected cell lines.

Anti-Bacterial Agents↗
PubMed1990

Significant myocardial pathology and increase of alpha 1-adrenergic receptor number affecting the arrhythmogenic condition in cases with ventricular tachycardia.

To study the pathogenesis of idiopathic ventricular tachycardia with left bundle branch block morphology (LBBB-VT), histopathological findings in 34 patients and adrenergic receptor (AR) density obtained by micro-autoradiography in 11 patients were analyzed, using endomyocardial biopsy samples. According to the ventricular volume, we divided the patients into 3 groups. Group A patients (n = 8) were diagnosed as having arrhythmogenic right ventricular dysplasia (ARVD) showing right ventricular enlargement, group B patients (n = 7) showed decreased left ventricular function and/or enlarged left ventricle, and group C (n = 19) included patients with idiopathic ventricular tachycardia (VT) without enlargement or dysfunction of either ventricle. Histologically, there was a high incidence of significant pathology showing myocardial hypertrophy, degeneration, abnormal branching, and interstitial fibrosis in all groups (group A, 100%; group B, 86%; group C, 56%). There was a higher incidence of fatty tissue infiltration in groups A (100%), B (71%), C (48%) than in the control groups. As for AR, specific grains of alpha 1- and beta-AR were 23.0, and 18.3 (grains/25 x 25 mm square) respectively, in patients with LBBB-VT. The number of alpha 1 grains in patients with LBBB-VT was apparently higher than in the control group, sick sinus syndrome (SSS; 11.2), and the beta-AR density in the LBBB-VT group was the same as in the control group (SSS; 15.4). We concluded that the significant pathology in cases with VT might affect the arrhythmogenic condition. Moreover, these results suggested that the increase in the number of alpha 1-AR might have a great influence in idiopathic VT.

Adult↗
PubMed1990

Glycine-insensitive NMDA-sensitive receptor expressed in Xenopus oocytes by guinea pig cerebellar mRNA.

The electrophysiological and pharmacological properties of N-methyl-D-aspartate (NMDA)-sensitive receptors expressed in Xenopus oocytes by injection of total poly(A)+RNAs (mRNAs) from the cerebellum and cerebrum of guinea pigs were compared. The inward current induced by NMDA under voltage-clamp in cerebellar mRNA-injected oocytes was depressed in a voltage-dependent fashion by Mg2+ to show a negative slope conductance and selectively antagonized by D-2-amino-5-phosphonovalerate (D-APV) and phencyclidine (PCP). Glycine (0.01-10 microM) did not potentiate NMDA-induced currents in cerebellar mRNA-injected oocytes, while it potentiated NMDA-induced currents in cerebral mRNA-injected oocytes in a dose-dependent fashion. 6-Cyano-7-nitroquinoxaline-2,3-dione and 7-chlorokynure-nate suppressed the NMDA response but significantly less potently in cerebellar mRNA-injected oocytes than in cerebral mRNA-injected oocytes. These results suggest that the NMDA-sensitive receptor expressed in Xenopus oocytes by guinea pig cerebellar mRNA resembles the cerebral NMDA receptor in its high sensitivities to Mg2+, PCP, and D-APV, but it is distinct from the cerebral NMDA receptor in responsiveness to glycine.

2-Amino-5-phosphonovalerate↗
PubMed1990

[Establishment and characterization of human pancreatic adenocarcinoma cell line SOJ producing carcinoembryonic antigen and carbohydrate antigen 19-9].

A new tumor cell line derived from a human pancreatic exocrine adenocarcinoma was established in tissue culture and was transplantable in a nude mouse. In tissue culture, the neoplastic cells grew as epithelial-like, mucin-producing cells with a population doubling time of 50-70 hrs. Chromosomes ranged from 63 to 186 with a modal number of 77. Subcutaneous injection of 1 x 10(6) cultured neoplastic cells into nude mice resulted in tumor formation histologically closely resembling the original neoplasm. Ultrastructurally, the cell line showed characteristic ductal epithelium. Immunohistochemically, carcinoembryonic antigen (CEA). Carbohydrate Antigen 19-9 (CA19-9) and DU-PAN-2 antigen were demonstrated in the original tumor, the culture cells and the transplanted tumor. The cells secreted CEA (48.7 ng/1 x 10(5) cells/24 hrs) and CA19-9 (325 U/1 x 10(5) cells/24 hrs) in spent medium as well as sera of the nude mouse. This cell line has been passaged 30 times in vitro and maintained for more than one year. These characteristics will make the cell line SOJ a valuable tool in studying various aspects of biology of human pancreatic cancer.

Adenocarcinoma↗
PubMed1990

Clinicopathological analysis of a patient with hypereosinophilic syndrome who demonstrated disseminated eosinophilic infiltration in various organs at autopsy.

A case (41 year old man) of idiopathic hypereosinophilic syndrome is presented. Typical eosinophilic endocarditis with restrictive cardiac failure and ventricular thrombosis was demonstrated by various clinical investigations, including cardiac pool scan and biopsy. The patient died after 22 months, and an autopsy revealed disseminated eosinophilic infiltration in the pancardium of the whole heart, aorta, main pulmonary artery, liver, and spleen.

Adult↗
PubMed1990

Histopathologic findings of endomyocardial biopsies in pediatric patients with arrhythmias or conduction disturbances.

Histopathologic findings of endomyocardial biopsy in 23 pediatric patients with arrhythmias or conduction disturbance were analyzed. ECG abnormalities consisted of atrioventricular block (AVB) in 11, ventricular arrhythmia including premature ventricular contractions (PVC) and ventricular tachycardia in 7, sick sinus syndrome (SSS) in 3, and bundle branch block in 2 cases. Biopsy specimens were obtained from the right ventricle in all cases and, additionally, from the right atrium in SSS cases. Biopsy revealed significant pathology in 19 cases (83%). Advanced histologic changes, including myocyte hypertrophy, disarrangement of muscle bundles, and interstitial fibrosis with or without myocyte degeneration, were observed in 7/11 AVB cases and 1/6 PVC cases. SSS cases showed interstitial fibrosis with disarrangement of muscle bundles in the right atrium, but no significant pathologic changes were seen in the right ventricle. There was no clinical evidence of hypertrophic or dilated cardiomyopathy, cardiac defects, or other heart disease in these patients. It is suggested that these cases may fall under the arrhythmia-conduction disturbance type of cardiomyopathy.

Adolescent↗
PubMed1990

High incidence of significant pathology in endomyocardial biopsy and familial occurrence in cases with arrhythmia and/or conduction disturbance.

In our series of studies of cardiomyopathy with endomyocardial biopsy in 1500 cases, we have noticed that there were a certain number of patients with arrhythmias and/or conduction disturbance who showed no evidence of hypertrophic or dilated form of caridiomyopathy but showed significant pathology in the biopsy. Significant pathology was determined when the biopsy findings from the right atrium and the right ventricle showed apparent pathology such as interstitial fibrosis, myocyte degeneration, and fragmentation of muscle bundles. Among 226 biopsied patients in whom arrhythmia and/or conduction disturbance were the main clinical feature, 85 patients (38%) demonstrated significant pathology in their biopsy. Familial occurrence was note-worthy among these patients. We propose that these cases should be grouped as nonhypertrophic, nondilated, and nonrestrictive cardiomyopathy, and suggest the term electric disturbance type of cardiomyopathy (ECM).

Arrhythmias, Cardiac↗
PubMed1990

Usefulness of electrophysiologic study and endomyocardial biopsy in differentiating arrhythmogenic right ventricular dysplasia from idiopathic right ventricular tachycardia.

Fifteen patients with right ventricular tachycardia without evidence of coronary artery disease or dilated or hypertrophic cardiomyopathy were evaluated, by means of electrophysiologic study and right ventricular endomyocardial biopsy. Six cases were diagnosed as definite arrhythmogenic right ventricular dysplasia (ARVD), while 2 cases without characteristic findings of ARVD by noninvasive studies and angiography were diagnosed as probable ARVD on the basis of their electrophysiologic and histopathologic data. In conclusion, ARVD is relatively common as an etiology of right ventricular tachycardia, and detailed electrophysiologic study and endomyocardial biopsy appear to be useful for diagnosis of ARVD.

Adolescent↗
PubMed1990

Hemodynamic and scintigraphic improvement after steroid therapy in a case with acute eosinophilic heart disease.

A 70-year-old woman with active hypereosinophilic myocarditis presented with high fever and heart failure. Repeated right ventricular endomyocardial biopsies and 201-T1 myocardial scans before and after steroid therapy suggested that this treatment reversed the cardiac injury. Patients with hypereosinophilia may die from complications of eosinophilic infiltration and fibrosis in target organs, especially the heart. The findings in this patient suggest that steroids have benefit in this disease, at least in the short term.

Acute Disease↗
PubMed1990

An atypical case of cardiomyopathy in a child: hypertrophic or restrictive cardiomyopathy?

A case of an atypical form of cardiomyopathy, in which biopsy showed bizarre myocardial hypertrophy with disorganization, and in which there was no obvious hypertrophy of the interventricular septum and left ventricular free wall, is presented. Ventricular filling was critically impaired, and consequently pulmonary and systemic venous congestion predominated in the clinical presentation which was similar to that of restrictive cardiomyopathy.

Biopsy↗
PubMed1990

[Two autopsied cases of arrhythmogenic right ventricular dysplasia].

Autopsy studies of arrhythmogenic right ventricular dysplasia (ARVD) have rarely been reported, and its etiology remains unknown. The present report describes a detailed histopathological study of two autopsied cases of ARVD. Case 1: This 21-year-old man experienced palpitation accompanied by syncope. He died after ventricular tachycardia of right ventricular origin. The heart weighed 365 g and the right ventricular cavity was markedly dilated. The distribution of fatty tissue was roughly limited to the middle layer of the free wall, replacing the myocardium with fatty degeneration. Medial hyperplasia of the small arteries within the fatty tissue was also observed. Fibroelastosis was observed in the left ventricular endocardium. In the conduction system, fatty tissue was found in the sinus node. In addition, medial hypoplasia was observed in the pulmonary arteries. Case 2: This 32-year-old man who had had an arrhythmia for 10 years died of ventricular tachycardia of right ventricular origin. His older brother also died of heart disease. His heart weighed 515 g and both the right and left ventricles were dilated. Fatty tissue, unlike that in Case 1, was shown to markedly infiltrate from the epicardium into both the right and left ventricular walls. In the right ventricular wall, muscle layers disappeared in some portions. In the conduction system, fatty tissue was observed in the sinus node. Although ARVD may be considered a syndromic entity, individual cases are different in terms of pathological morphology, with possible variations in the etiology and pathogenesis.

Adipose Tissue↗
PubMed1990

[A case of marked effectiveness using medroxyprogesterone acetate (MPA) in lung metastases of cancer of the uterine body].

This case is a 71-year-old female. As hormonotherapy, 400 mg/day of MPA alone was orally administered in a lung metastatic case of cancer of the uterine body in the IV stage. Although progressing for 2 years and 1 month after the initial administration, lung metastatic foci disappeared, and recurrence was not noted, and serious side effect by using MPA was also not noted. Progesterone therapy such this case is considered as one of therapeutic methods which can be expected remarkably effective rate in the lu metastatic foci of cancer of the uterine body.

Administration, Oral↗
PubMed1990

[Radionuclide assessment of cardiac involvement in patients with sarcoidosis].

This study was aimed to determine whether nuclear methods were useful for examining cardiac pathology and for making a decision of corticosteroid therapy in patients with sarcoidosis. Thirty six patients were divided into two groups; GpA consisted of 19 patients with cardiac sarcoidosis and abnormal ECG findings, and GpB of 17 patients with sarcoidosis without ECG abnormalities. Cardiac uptake of 67Ga-citrate in 2 and 99mTc-PYP in one of GpA was observed and steroid therapy resulted in the disappearance of the uptake. 201Tl-CL cardiac tomograms disclosed perfusion defects in 10 of 14 patients (71%) in GpA, including defects with redistribution in 8 of the 10 pts, but only one case in GpB. Radionuclide ventriculography using 99mTc-RBC revealed abnormal response of left ventricular (LV) function to exercise and LV dysfunction in GpA. These data suggest that nuclear study is a useful tool for diagnosing cardiac sarcoidosis, evaluating therapeutic effectiveness and long-term follow-up in patients with sarcoidosis.

Adult↗
PubMed1990

[Arachidonic acid metabolites on peripheral blood plasma in patients with bronchial asthma].

To assess the role of arachidonic acid metabolites in pathogenesis of bronchial asthma, we measured thromboxane B2 (TxB2), 6-keto PGF1 alpha, leukotriene (LT) C4, and LTB4 in venous blood plasma in patients with bronchial asthma and in controls. The level of TxB2 was significantly higher in 18 asthmatics with attacks than that in 11 controls (77.3 +/- 48.8 pg/ml vs 48.8 +/- 9.4 pgml). The levels of 6-keto PGF1 alpha in both asthmatics with attacks (17.8 +/- 6.7 pg/ml) and without an attack (16.4 +/- 9.7) were significantly higher than that in controls (11.6 +/- 3.9 pg/ml). The levels of LTC4 in asthmatics with attacks (0.84 +/- 0.11 ng/ml, n = 11) were significantly higher than that in controls, furthermore the level of LTC4 in asthmatics without an attack. The level of LTB4 was significantly higher in asthmatics with attacks (295.0 +/- 160.7 pg/ml, n = 26) than that in controls (161.7 +/- 25.3 pg/ml, n = 12) and asthmatics without an attack (182.4 +/- 97.9 pg/ml, n = 22). These findings suggest that the arachidonic acid metabolites are related to the asthma attack and are associated with the pathogenesis of bronchial asthma.

6-Ketoprostaglandin F1 alpha↗