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Biomedical subjects

N Sugihara

Publications and source records attributed to N Sugihara.

At least 55 records · Page 3Linked to original sources
PubMed1991

Left atrial afterload mismatch in hypertrophic cardiomyopathy.

To investigate left atrial (LA) booster pump function in hypertrophic cardiomyopathy (HC), LA and left ventricular pressure-volume loops were estimated in 5 control subjects, 6 patients with essential hypertension and 11 patients with HC. Investigation of LA preload revealed that LA pressure and volume immediately before LA contraction were both increased in patients with hypertension (10 +/- 5 mm Hg, 71 +/- 19 ml/m2) compared with control subjects (7 +/- 1 mm Hg, 59 +/- 6 ml/m2), and even more increased in patients with HC (16 +/- 7 mm Hg, 81 +/- 25 ml/m2). Investigation of LA afterload revealed that the left ventricular chamber stiffness constant was higher in patients with hypertension (0.035 +/- 0.015) than in control subjects (0.028 +/- 0.009), and even more increased in patients with HC (0.056 +/- 0.017). LA stroke work index was higher in patients with hypertension (116 +/- 34 mm Hg.ml) and HC (115 +/- 19 mm Hg.ml) than in control subjects (87 +/- 23 mm Hg.ml). Investigation of LA ejection revealed that LA stroke index was higher in patients with hypertension (24 +/- 5 ml/m2) than in control subjects (18 +/- 4 ml/m2) and patients with HC (18 +/- 2 ml/m2), and LA ejection fraction was lower in patients with HC (23 +/- 6%) than in control subjects (32 +/- 7%) and patients with hypertension (34 +/- 8%). In patients with HC, LA function curve showed a shift to the lower right, and LA stroke index was inversely correlated (r = -0.76) with LA afterload. This study suggests that LA booster pump failure due to LA afterload mismatch exists in HC.

Adult↗
PubMed1991

Distribution of fluoride in sound and periodontally diseased human cementum.

Fluoride distribution was investigated by an abrasive micro-sampling technique. The fluoride concentration increased with age in both sound and diseased cementum. In sound teeth, the fluoride profiles (distribution of fluoride from the surface to interior) of the middle and apical cementum were similar. In the diseased cementum the profile of the middle region tended to be more variable than that of the apical cementum, suggesting a possible effect of the oral environment on the fluoride profile at this site.

Adult↗
PubMed1991

Correlation between histopathological changes and mechanical dysfunction in diabetic rat hearts.

Recent clinical and experimental studies have suggested that diabetic patients may develop myocardial dysfunction in the absence of coronary heart disease and hypertension. In this study, the correlation between histopathological changes and myocardial dysfunction was studied in experimental diabetic rat hearts. Male Wistar rats were made diabetic at 9 weeks of age with a single intravenous injection of streptozotocin 50 mg/kg. The diabetic rats were studied along with age-matched control and insulin-treated rats at 4, 8, 12 and 24 weeks after the induction of diabetes to investigate isolated papillary muscle contraction and the histopathological picture simultaneously. In the isometric contractions, resting and developed tensions were similar. Time to peak tension and time to 1/2 relaxation were prolonged and the peak rate of tension rise and tension fall was depressed. On histological examination of left ventricular walls, diameters of myocytes were similar at all disease durations. Interstitial fibrosis and disarrangement of myocytes after 12 weeks were slightly increased in the diabetic hearts. Mechanical parameters did not worsen in parallel with the duration of diabetes and histological changes, but correlated with the blood glucose level. These data suggest that short-term mechanical defects in the experimental diabetic rat heart result from the metabolic disorder itself, with histopathological changes occurring later.

Animals↗
PubMed1991

Increase in the plasma protein binding of weakly basic drugs in carbon tetrachloride-intoxicated rats.

Plasma protein binding of weakly basic drugs such as propranolol and quinidine was determined in rats with carbon tetrachloride (CCl4)-induced hepatic disease. Free fractions of propranolol and quinidine in the plasma of rats at 24 h after CCl4-intoxication were decreased by 41 and 30%, respectively, compared to those of control rats. An addition of Tris (butoxyethyl) phosphate (TBEP), a specific displacer for basic drugs from alpha 1-acid glycoprotein (AGP), to the plasma increased the free fractions of the basic drugs, resulting in no difference in the extent of the plasma free fraction of each drug between control and CCl4-intoxicated rats. Plasma concentration of AGP in CCl4-intoxicated rats was elevated 2.7-fold of that in control rats at 24 h after the CCl4 intoxication and reached a peak of 4.8-fold elevation at 48 h. A regression analysis revealed a high degree of positive correlation between ratios of bound to free fraction of propranolol and plasma concentrations of AGP. These results suggest that the plasma protein binding of the basic drugs was increased mainly due to the rise in the plasma AGP concentration in CCl4-intoxicated rats.

Animals↗
PubMed1991

Increase in left ventricular chamber stiffness in patients with non-insulin dependent diabetes mellitus.

Indices of left ventricular ejection and diastolic filling were measured by cineventriculography in 11 patients with non-insulin dependent diabetes mellitus without significant coronary stenosis and 11 control subjects without diabetes mellitus. Indices of left ventricular ejection, such as ejection fraction and peak ejection rate, were the same in the two groups. The left ventricular end-diastolic volume index and the rapid filling volume index were significantly smaller, the peak filling rate was lower, the left ventricular end-diastolic pressure was higher and the modulus of left ventricular chamber stiffness was larger in the diabetic patients than in the control subjects. These results indicate that left ventricular chamber stiffness is increased in patients with non-insulin dependent diabetes mellitus.

Adult↗
PubMed1991

[A case of tricuspid annular calcification].

A 76-year-old man was referred to our hospital with complaints of productive cough, dyspnea and peripheral cyanosis. The chest X-ray film indicated the pulmonary emphysema and acute bronchitis, but no abnormal intracardiac calcification. The electrocardiogram revealed a peaked P-wave, complete left bundle branch block, and ventricular premature contraction. Chest tomography demonstrated abnormal intracardiac calcium deposition in the right heart region. Two-dimensional echocardiography revealed the tricuspid annular calcification in the postero-lateral portion, showing a synchronous movement with tricuspid annular motion throughout the cardiac cycle. The size of calcification was 10 x 14 mm. The tricuspid valve showed no significant regurgitation. Left ventricular dilatation, associated with mild mitral regurgitation and impairment of systolic function (EF = 49%) was revealed by echocardiography. Serum examination revealed positive in Wassermann reaction. This case of tricuspid annular calcification might be caused by atherosclerotic degenerative change related to the aging process, or by an unknown mechanism related to pulmonary emphysema.

Aged↗
PubMed1990

[Assessment of the relation between bone mineral metabolism and mitral annular calcification or aortic valve sclerosis--the relation between mitral annular calcification and postmenopausal osteoporosis in elderly patients].

We assessed the effect of bone mineral metabolism on mitral annular calcification (MAC) and aortic valve sclerosis or calcification (AVS) in elderly patients. Both MAC and AVS were derived by 2-D echocardiography, and bone mineral content (BMC) of vertebral bodies was obtained by quantitative computed tomography using a calibrated phantom system. The calcium (Ca), phosphate (P), parathyroid hormone (PTH-c), calcitonin (CLT), vitamin-D (25-(OH)D) and osteocalcin (OC) in serum were examined within a period of one month. The 265 patients were classified into three groups according to the echocardiographic findings. The control (CNT) group consisted of 122 patients (44 males, 78 females) without MAC or AVS, the MAC group consisted of 64 patients (16 males, 48 females) with MAC, and the AVS group consisted of 79 patients (31 males, 48 females) with AVS. 1) The incidences of MAC and AVS in both males and females were found to increase in proportion to aging. 2) The incidence of MAC in females (28%) was higher than that of males (18%). 3) AVS in males (34%) was more frequent than in females (27%). 4) In females of the eighth and ninth decade of age, BMC in the MAC group was significantly less than in the CNT group (eighth p less than 0.05, ninth p less than 0.01), but no difference was seen in males. 5) In both males and females, BMC in the AVS group was not significantly different from that in the CNT group. 6) In all subjects of the eighth and ninth decades, the serum levels of Ca and P were within normal ranges. PTH-c, CLT and 25-(OH)D showed subnormal or lower normal values, while OC showed supernormal or upper normal values. However, the was no difference among the three groups. These results suggest that MAC may be attributed to ectopic calcium deposit, probably related to decalcification from bone in postmenopausal osteoporosis. However, in the present study, there was no relation between the incidence of MAC and humoral factors of calcium metabolism. On the other hand, AVS may be caused by other factors, mainly prolonged and sustained pressure or stress loading.

Aged↗
PubMed1990

[Early diastolic dysfunction of the left ventricle and its relation to histopathological findings in patients with diabetes mellitus].

The relation of left ventricular diastolic function and the histopathological findings of the myocardium in patients with diabetes mellitus were observed using echocardiography and endomyocardial biopsy. The subjects consisted of six diabetic patients (mean age 49.3 years) and eight normal control subjects (mean age 44.8 years). Coronary angiography had no significant stenotic lesions in their coronary arteries. Their diabetic complications were mild to moderate in severity. Echoes from the left ventricular margin of the septum and from the posterior left ventricular wall were traced on a digitizing board; then the isovolumic relaxation period, rapid filling period, slow filling period and atrial contraction period were determined to calculate fractional shortening (FS), isovolumic relaxation time (IRT), and three filling volumes (RFV, SFV and ACV). The quotients of the left ventricular filling volume and stroke volume were also determined. Right ventricular endomyocardial biopsies were performed to determine the diameters of myocytes, the percentage of fibrosis and the eccentricity e, as a parameter of the degree of myocardial dysarrangement. The results were as follows: IRT was significantly longer and RFV/SV was significantly greater in patients with diabetes mellitus than those among the controls. Also the diameters of myocytes and the percentage of fibrosis were significantly greater, while the eccentricity e was less compared to that of the controls. There were no significant correlations, among IRT, RFV/SV, the diameters of myocytes, and eccentricity e, but the percentage of fibrosis significantly correlated with IRT and RFV/SV (r = 0.62, r = -0.63). IRT and RFV/SV were mainly responsible for the percentage of fibrosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Early diastolic dysfunction of the left ventricle affected by hypertrophy and abnormal histopathology in hypertrophic cardiomyopathy].

In this study, we investigated correlations of left ventricular hypertrophy and its histopathology with diastolic dysfunction in patients with hypertrophic cardiomyopathy. Nine control subjects and 14 hypertrophic cardiomyopathy (HCM) patients with asymmetrical septal hypertrophy were evaluated. M-mode echocardiography was used to assess fractional shortening (FS), isovolumic relaxation time (IRT), and the left ventricular filling volume index during rapid and slow filling periods and atrial contraction period (RFVI, SFVI and ACVI). End-diastolic thickness of the interventricular septum and posterior wall was determined using biventriculography. Right ventricular endomyocardial biopsies were performed to calculate the diameters of myocytes, the percentage of fibrosis and the eccentricity e which indicates the degree of myocardial disarrangement including disorganization. The FS was normal in the two groups. The IRT of the HCM group was significantly greater and the RFVI significantly less than those of the controls. The left ventricular wall thickness, the diameters of myocytes and the percentage of fibrosis in the HCM group were significantly greater; and the eccentricity e was significantly less, suggesting that myocardial disarrangement was significantly more severe than that in the controls. Significant positive correlations were observed between the IRT and the wall thickness (r = 0.647), between the diameter of myocytes (r = 0.681) and the percentage of fibrosis (r = 0.628), and there was a significantly negative correlation between the IRT and the eccentricity e (r = -0.759). There was a significantly negative correlation between the RFVI and the wall thickness (r = -0.663); and a significantly positive correlation between the RFVI and the eccentricity e (r = 0.579). Multiple regression analyses showed that the diameter of myocytes, the percentage of fibrosis and the eccentricity e all correlated significantly with the IRT (R = 0.821) and the RFVI (R =0.604). The standard regression coefficients of the diameter of myocytes, the percentage of fibrosis and the eccentricity e were 0.253, 0.278 and -0.431 in respect to IRT, and those of the percentage of fibrosis and the eccentricity e were -0.204 and 0.469 in respect to RFVI, respectively. These results indicated that diastolic dysfunction in hypertrophic cardiomyopathy is related not only to the degree of left ventricular hypertrophy, but also to the degree of myocardial hypertrophy, increased interstitial fibrosis, and especially to myocardial disarrangement including disorganization.

Adult↗
PubMed1989

Serial electrocardiographic and angiographic changes of patients with hypertrophic cardiomyopathy.

The characteristics of ECG findings as they relate to myocardial changes during long-term course of hypertrophic cardiomyopathy (HCM) were studied. Serial changes in ECG were compared with changes left ventriculogram and bi-ventriculogram in 15 patients with HCM without intraventricular conduction disturbance. Serial changes in ECG findings, with special reference to the negative T wave, were categorized in three groups; 1) 5 patients with increase or appearance of the negative T wave (A-1 group). 2) 4 patients with decrease or disappearance of the negative T wave (A-2 group). 3) 6 patients without significant changes in the T wave (B-group). A-1 group presented a marked increase in SV1 + RV5, and of the thickness of anterior and apical wall, and a decrease of the peak dV/dt/EDV (end diastolic volume-normalized peak filling rate), serially. End diastolic volume (EDV) and ejection fraction (EF) did not change significantly. The configuration of left ventriculogram changed from a round form to a spade-like form. A-2 group presented a marked decrease in SV1 + RV5, the thickness of anterior and apical wall, peak dV/dt/EDV and peak dV/dt/V (left ventricular volume of the time of peak filling-normalized peak filling rote). EF decreased serially, 2 cases of A-2 group presented the clinical picture of dilated cardiomyopathy in the end stage. In B group, SV1 + RV5, the wall thickness and left ventricular function did not change, serially. In conclusion, serial observations of ECG are useful for assessing alterations in wall thickness, LV-form and LV-function.

Adult↗
PubMed1989

[Ectopic calcification of the abdominal aorta and bone mineral content of vertebrae].

The relationship between the ectopic calcification of abdominal aorta and the de-calcification of bone in 137 elderly patients was investigated by quantitative computed tomography. We calculated the index (CAI) of the calcification volume to the aorta volume in the lower abdominal aorta, and simultaneously estimated the bone mineral content (BMC) of the vertebral body using a calibration phantom. The CAI increased and the BMC decreased progressively in proportion to aging. There was a significant negative correlation between the CAI and the MBC in females in the eighth and ninth decades (eighth decade: n = 37, r = -0.400; p less than 0.01, ninth decade: n = 37, r = -0.334; p less than 0.05). These results suggested that in elderly females, abdominal aortic calcification is closely related to de-calcification from the vertebral body.

Aged↗
PubMed1989

[Assessment of the relation between bone mineral metabolism and mitral annular calcification or aortic valve sclerosis in elderly patients].

We assessed the effect of bone mineral metabolism on mitral annular calcification (MAC) and aortic valve sclerosis (AVS) in elderly patients. Both MAC and AVS were derived by 2-D echocardiography and bone mineral content (BMC) of vertebral body was obtained by quantitative computed tomography using a calibrated phantom system. The 162 patients were classified according to the echocardiographic finding into three groups; CNT group consisted of the 79 control patients (31 males, 48 females) without MAC or AVS. MAC group: 42 patients (11 males, 31 females) with MAC, and AVS group: 41 patients (19 males, 22 females) with AVS. The results were as follows: 1) The incidence of MAC and AVS in both males and females were increased in proportion to aging. 2) The incidence of MAC in females (31%) was higher than that of males (18%). 3) The AVS in males (31%) was more frequent than that in females (22%). 4) In females of eighth and ninth decades, the BMC in MAC group was significantly decreased than that in CNT group, but not different in males. 5) In both males and females, the BMC in AVS group was not significantly different from that in CNT group. These results suggest that the MAC may be attributed to the ectopic deposit, probably related to the de-calcification from the spinal bone. On the other hand, the AVS may be caused by the other factors, mainly prolonged and sustained pressure or stress loading.

Aged↗
PubMed1989

[A case of bilateral coronary artery to pulmonary artery fistulas associated with hepatic arteriovenous fistula].

A 55-year-old man, previously treated for primary hypothyroidism, was admitted for evaluation of atypical chest pain. On physical examination, the pulse rate was 60 and blood pressure was 132/84 mmHg. Heart sounds were normal and no murmur was heard. Abdominal palpation showed no abnormal finding, and bruit was not heard. The electrocardiogram was normal and stress-induced ischemia was not found. The chest X-ray showed no sign of pulmonary hyperaemia or mass lesion, and central shadow was normal (CTR = 44%). During right heart catheterization, the pressures were normal in the cardiac chambers, pulmonary artery, and wedge position. A significant increase in oxygen saturation was disclosed at pulmonary artery level (10%) and the upper site of the inferior vena cava (22%). Coronary arteriography found coronary artery fistulas from the left main trunk, the left anterior descending artery, the left circumflex, and the right coronary artery to the pulmonary trunk. The left and right ventriculograms were normal. The digital subtraction angiography of celiac artery showed hepatic arteriovenous fistula. Ultrasonography and computed tomography found no mass lesion of the liver. Since combination of the bilateral coronary artery with pulmonary artery fistula, and hepatic arteriovenous fistula is very rare, the present case is worth noting for the investigation of the pathogenesis of congenital arteriovenous fistulas.

Arterio-Arterial Fistula↗
PubMed1989

[Dental health status of junior high school students in the suburbs of Chiba city].

The Population of 12-15 years is a key age group for oral health because the permanent dentition and periodontal tissues are almost complete at this stage. The purpose of this study was to evaluate oral health status and to develop an effective school dental health program for junior high schools students. The survey was performed on 527 persons aged 12-13 at 2 junior high schools in the suburbs of Chiba city. Periodontal disease was evaluated on the basis of the CPITN, and analyzed for severity and region of periodontal disease. Gingivitis was examined with PMA index, using color photo slides taken of anterior dentition at the time of inspection. At the same time, caries experience and oral hygiene index were also estimated. The results were as follows: (1) The mean DMFT was 3.89. Caries prevalence in females was higher than males. Ratio of treated teeth rate was 77.03%; that of untreated teeth rate was 22.65%. Females revealed less treatment for caries than males. Oral hygiene index showed significant difference between males and females. Labial and buccal parts of the maxillary and molar region on the mandibular showed remarkable plaque deposition. Calculus accumulation in this population was greatest on the lower incisor. (2) The mean PMA index was 7.36. Gingivitis was highly prevalent in both sexes, although it was more severe in males. There was correlations between PMA index and OHI. (3) From the results of CPITN, 10.6% of the subjects showed no signs of periodontal disease (Code 0), and 5.7% exhibited gingival bleeding (Code 1).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

[Distribution of dental plaque and time analysis of toothbrushing without instruction in school children and students].

The purpose of this study is to evaluate oral hygiene before and after individual method toothbrushing without instruction and to analyze toothbrushing times for school children from 6 to 13 years of age. Subjects were 150 pupils from primary to junior high school affiliated with the faculty of education of an university located in Setagaya, Tokyo: 38 first-grade pupils aged 6, 36 fourth-grade pupils aged 9, 37 sixth-grade pupils aged 11, and 39 second-year junior high school pupils aged 13. Assessments of dental plaque were made by two dentists using the PHP plaque score (Podshadely and Haley, 1968) for primary school pupils and OHI-S (only DI-S; Greene and Vermillion, 1964) for junior high school pupils. Plaque distribution disclosed by an Erythrosine solution was examined before and after toothbrushing, and the performance of toothbrushing by subjects was recorded on video-tape through a one-way mirror so that the children were unaware. Toothbrushing time was measured by 2 or 3 examiners using a time counter of video-monitor. Average scores for dental plaque before and after toothbrushing were almost the same for first and fourth-grade primary school pupils; but scores decreased with a statistically significant difference (p less than 0.01) for sixth-grade pupils. Distribution patterns of plaque scores for fourth-grade pupils showed characteristically narrow ranges (2-5 before brushing and 1-4 after brushing). The majority of subjects (69.4%) had scores of 2-3 after brushing, Whereas only 8.3% showed a range of 2-3 before brushing.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

Quantitation of myocardial fibrosis and its relation to function in essential hypertension and hypertrophic cardiomyopathy.

Myocardial interstitial fibrosis is an important microscopic feature of hypertrophic cardiomyopathy. To determine whether interstitial fibrosis of the myocardium in hypertrophic cardiomyopathy and essential hypertension differ in quality or quantity, and to determine whether fibrosis affects cardiac function directly, we measured the percentage of fibrosis in patients of both categories and compared the severity of fibrosis with several cardiac functions. Left and right ventricular endomyocardial biopsies were performed in 25 patients with essential hypertension and in 19 patients with hypertrophic cardiomyopathy. Interstitial fibrosis was classified into four different microscopic types, and the percentage of total and of each type was calculated using the point-counting method. Although the percentage of total fibrosis was similar between the two groups, the type of fibrosis was different. There was no correlation between the percentage of total fibrosis and the mean size of myocytes in either group. Although there was a significant correlation between the percentage of total fibrosis and the thickness of the interventricular septum in hypertrophic cardiomyopathy, such correlation was lacking in hypertension. There was no correlation between the percentage of total fibrosis and the ejection fraction, cardiac index, or left ventricular end-diastolic pressure in either group. We concluded that the amount of myocardial interstitial fibrosis in hypertrophic cardiomyopathy is no greater than that in essential hypertension, but the type of fibrosis is different. Furthermore, in subjects in whom the ejection fraction is normal or only slightly decreased, fibrosis does not influence global cardiac functions.

Adult↗