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Biomedical subjects

Y Tsumura

Publications and source records attributed to Y Tsumura.

At least 19 recordsLinked to original sources
PubMed1992

[Left atrial ejection performance in heart failure as assessed by transesophageal Doppler echocardiography].

To investigate the left atrial ejection performance in heart failure, we observed both the transmitral (TMF) and pulmonary venous flow waves (PVF) by transesophageal Doppler echocardiography in 20 patients with heart failure (16 males, 4 females, 56 +/- 13 years old). In 7 of 20 patients, pulmonary capillary wedge pressures (PC) were also obtained within 72 hours after the transesophageal Doppler echocardiographic examinations. A reversal flow on PVF during atrial systole (atrial backward ejection flow) was observed in all of the 20 patients. Corrected atrial pre-ejection period correlated significantly with PC (r = -0.76, p < 0.05), indicating that the period was shortened in accordance with left atrial Starling's law. This period correlated significantly with both the duration and the time velocity integral of atrial backward flow (r = -0.72, p < 0.005; r = -0.55, p < 0.05, respectively), but not with the atrial ejection time nor with the time velocity integral of atrial systole. These results suggest that in some cases of heart failure, left atrial contractile function is preserved despite the marked augmentation of left atrial afterload, resulting in a decrease of the left atrial forward ejection and an increase of the left atrial backward ejection. Thus, the observations of TMF and PVF by transesophageal Doppler echocardiography are useful for assessing the left atrial ejection performance in patients with heart failure.

Adult↗
PubMed1992

[Clinical and echocardiographic evaluation of the effects of atrial defibrillation in patients with idiopathic cardiomyopathy].

To elucidate the effects of atrial defibrillation in patients with idiopathic cardiomyopathy, we clinically and echocardiographically assessed 6 patients with hypertrophic cardiomyopathy (HCM) and 7 patients with dilated cardiomyopathy (DCM). Their mean age was 57 +/- 14 years and the mean duration of their atrial fibrillation (Af) was 47 +/- 29 days. There were no differences in age and the duration of Af between the HCM and DCM groups. We assessed the effects of defibrillation on the NYHA functional classification, heart rate (HR), systolic blood pressure (S-BP), M-mode echocardiographic data (LVDd, LVDs, %FS, LAD) and transmitral pulsed Doppler echocardiographic findings (peak velocity, time-velocity integral of rapid and atrial filling waves). These indices were obtained before and 52 +/- 22 days after defibrillation, and were compared with each other. 1. HR decreased (HCM: 87 +/- 16-->58 +/- 7/min, DCM: 93 +/- 19-->70 +/- 14/min) and total left ventricular filling increased (HCM: 6 +/- 1-->11 +/- 4 cm, DCM: 6 +/- 1-->10 +/- 2 cm) after defibrillation, and the increment of %FS (HCM: 36 +/- 6-->41 +/- 6%, DCM: 16 +/- 6-->25 +/- 11%) was observed. Four of 6 HCM patients and 5 of 7 DCM patients also improved with regard to the NYHA classification. 2. After defibrillation, LVDd increased in HCM (42 +/- 4-->47 +/- 4 mm), but not in DCM. However, LVDs decreased in DCM (52 +/- 9-->44 +/- 12 mm), but not in HCM. We concluded that atrial defibrillation had a beneficial effect on the recovery of the left ventricular function both in HCM and DCM due to the reduction in HR and increase in left ventricular filling. The mode of LV functional improvement after defibrillation varied depending on the state of patient's basal pathophysiology .

Adult↗
PubMed1992

[Studies on the analysis of copper chlorophyll and sodium copper chlorophyllin in imported foods].

The analysis of copper chlorophyll (CuCh) and sodium copper chlorophyllin (CuCh-Na) in imported foods was carried out. Standards of CuCh and CuCh-Na were examined by ultraviolet and visible spectrophotometer. CuCh gave absorption maximum around 650 nm, while CuCh-Na gave around 630 nm. Imported sweets and liqueurs were homogenized and extracted with ethyl acetate. These extracts also gave absorption maxima absorbance around 650 nm or 630 nm. The results suggested that a distinction between CuCh and CuCh-Na in foods was possible by spectrophotometry. Visible spectrophotometric quantitation was also tried. However the estimated levels of CuCh or CuCh-Na in the samples by this method did not meet with those by atomic absorption spectrometry.

Chlorophyllides↗
PubMed1992

[Analytical results of post-harvest pesticides in citrus fruits and fruits juices by GC-MS (SIM) and HPLC with fluorescent detector].

Determination of 6 kinds of post-harvest pesticides (DP, OPP, TBZ, 2,4-D, Imazalil and Benomyl) in citrus fruits and fruits juices was carried out by GC-MS (SIM) and HPLC with fluorescent detector. DP for 16 samples, OPP for 27 samples, TBZ for 12 samples, 2,4-D for 10 samples, imazalil for 20 samples and Benomyl for 4 samples were detected in total 32 samples.

Beverages↗
PubMed1992

Determination of organophosphorus pesticides in imported foods by FPD-GC and GC-MS.

Organophosphorus pesticides in 47 agricultural products imported at the Yokohama and Kobe Quarantine Station in 1990 were determined by FPD-GC and identified by GC-MS. Chlorpyrifosmethyl, malathion and fenitrothion were found in wheat (0.03-0.69 ppm), chlorpyrifosmethyl and fenitrothion in soy bean (0.02-1.03 ppm), chlorpyrifosmethyl in cherry (0.12-0.17 ppm), chlorpyrifosmethyl in pumpkin (0.07-0.15 ppm), chlorpyrifosmethyl and malathion in corn (0.15-1.38 ppm).

Chromatography, Gas↗
PubMed1991

Effects of long-term beta-blockade (metoprolol) therapy in patients with dilated cardiomyopathy.

Twenty-two patients with dilated cardiomyopathy (DCM) were treated with metoprolol and their clinical courses were compared with those of 26 patients untreated with beta-blocking agents (non beta group). Of the 22 patients treated with metoprolol, 19 (beta group) were treated for a long period, 3 patients left the study within its first 6 months. Using the NYHA classification, 4 patients of the beta group were evaluated as having clinically improved, while none was aggravated, excluding 2 cases of death which occurred during the follow up period. In the non-beta group, clinical improvement was found for 2 patients and aggravation in functional class for 10. The left ventricular diameter was significantly decreased and parameters of systolic function and exercise tolerance were significantly improved in patients of the beta group, while no such improvements occurred in patients of the non-beta group. Twenty-four-hour ECG monitoring demonstrated a significant reduction in incidences of ventricular extrasystole in the beta group but not in those of the non-beta group. Improvement of arrhythmias, evaluated using Lown's grading system, was also identified more frequently in the beta group than in the non-beta group. During the follow-up period, 2 patients of the beta group and 10 patients of the non-beta group died. The survival curve for patients of the beta group prepared using the Caplan Meier Method was better than that for patients of the non-beta group. Metoprolol was therefore found to be useful for treatment of DCM.

Arrhythmias, Cardiac↗
PubMed1990

[A case of emphysematous cystitis].

Emphysematous cystitis is a rare but interesting disease. A case is reported of cystitis emphysema with acute pyelonephritis and uncontrolled diabetes. The patient was a 54-year-old woman complaining of gross hematuria and fever. A submucosa emphysema in bladder was found by cystoscopy . Radiography showed the gas around the bladder. The patient was administered antibiotics, then symptoms was improved. We reviewed 12 cases of emphysematous cystitis reported in Japan and summarized the pathophysiologic features of this entity.

Acute Disease↗
PubMed1989

[A case of herniation of the bladder].

A 34-year-old man was admitted with pain on urination, pollakisuria and left inguinal hernia. He had undergone a surgery for the left inguinal hernia 3 times, about 30 years, 28 years and 14 years earlier. Physical examination revealed that there was an elastic soft mass in the left inguinal region. Cystoscopy and cystography showed the bladder herniation and left vesicoureteral reflux (Grade 1). Radical surgery for the hernia of bladder was not performed. The literature on the hernia of the bladder in Japan were collected and discussed.

Adult↗
PubMed1989

[Clinical study of estramustine phosphate (Estracyt) on prostatic cancer].

Clinical effect of Estracyt was investigated in prostatic cancer patients. Twenty seven patients had been previously treated and 20 had not received prior treatment. Improvement rate of subjective symptoms was 85% in the previously untreated patients and that of objective findings was 85%, while those rates were 44% and 50% in the previously treated patients, respectively. Most of the adverse reactions were changes in mamma and mammary papilla which were considered to be due to the estrogenic activity.

Aged↗
PubMed1979

Insulin release and metabolism of calcium, adenine and adenosine 3',5'-cyclic monophosphate.

In order to assess further the mechanisms involved in insulin release, we prelabeled rat pancreatic islets of Langerhans by incubating either 45Ca or [2-3H]adenine. When prelabeled islets were perfused with a glucose-free medium (the experiment with 45Ca) and a medium containing 2.8 mM glucose (the experiment with [2-3H]adenine) respectively, a constant rate of efflux of the radioactivity was established by 30 min in each case. D-Glucose at 16.7 mM concentration elicited a rapid efflux of 45Ca and [2-3H]adenine derivatives ([3H]Ad) within 4 to 6 min after commencing the step-wise stimulation by glucose, concomitantly with insulin release. However, L-glucose and D-galactose littel stimulated both 45Ca and [3H]Ad release. Lanthanum chloride caused a burst peak of 45Ca release in the absence of glucose. A rapid efflux of 45Ca was caused by beta-D-glucose and D-glyceraldehyde to much lesser extent than by alpha-D-glucose. The slowly rising concentration of glucose at 0.1 mM/min of gradient level failed to elicit any rapid efflux of 45Ca or [3H]Ad, although insulin release occurred in accordance with an increase in glucose concentration. Even when the gradient of glucose concentration was raised to 0.7 mM/min, glucose failed to stimulate an efflux of [3H]Ad but the subsequent stimulation by 16.7 mM glucose caused a rapid efflux of [3H]Ad concomitantly with the release of insulin. No rapid efflux of 45Ca was observed under a slow-rise glucose stimulation until the gradient level of the glucose concentration was raised to 6.7 mM. Analysis of distribution of the radioactive adenine derivatives after incubation showed that the adenosine fraction had the highest radioactivity in the medium followed by the ATP, adenine and cAMP fraction in that order, and the ATP fraction had the highest radioactivity in the islet. The ratio of radioactivity in the cAMP fraction in the medium to the total count was the highest among all. On the basis of these results, it was suggested that the discharge of [3H]Ad and 45Ca might occur with the alteration of the membrane permeability induced by a rapid change of the glucose concentration, and that their discharge might perhaps link to the glucoreceptor mechanism directly controlling insulin release.

Adenine↗
PubMed1979

Insulin release and eflux of [32P]Phosphate from islets of rat Langerhans treated with iodoacetic acid and the anomers of D-glucose.

To clarify the insulin-releasing mechanism, we studied insulin release and the efflux of [32P]phosphate by glucose at 0.1 mM/min of gradient level or at 16.7 mM, and other metabolism in islets of rat Langerhans. When treated with 1 mM iodoacetic acid (IAA) plus the anomers of D-glucose at 2.8 mM for 6 min at 37 degrees C, islets elicited insulin at half the control rate under the step-wise stimulation by glucose and at the same rate as the control under the slow-rise stimulation by glucose. Using islets treated with IAA plus the alpha anomer at 16.7 mM, the step-wise stimulation secreted insulin at half a rate of the control and the slow-rise stimulation at the rate lower than the control, which was not significantly different from the control rate. Treatment with IAA plus the beta anomer at 16.7 mM inhibited insulin release under both types of stimulations by glucose. The step-wise stimulation caused the same rapid efflux of [32P]phosphate from IAA-treated islets as from the control islets, except for islets treated with IAA plus the beta anomer at 16.7 mM. The rate of glucose utilization in islets was inhibited by all IAA-treatments to the same extent, being merely half the control rate. Treatments with IAA plus the anomers at 16.7 mM significantly reduced the formation of [3H]-cAMP and the activity of protein phosphokinase in islets, while in the presence of the anomers at 2.8 mM IAA produced no significant effect. Neither IAA-treatments altered the uptake of 45Ca and the ATP content in islets. The uptake of [14C]IAA was significantly enhanced by the presence of the beta anomer at 16.7 mM to two times the control level. On the basis of these results, we suggested that the B cell might contain both glucoreceptors and rate-sensors of glucose controlling insulin release and the former might be less sensitive to IAA as compared with the latter.

Animals↗
PubMed1977

Sensitized effect of prestimulation on insulin release from the perifused rat islets with a slow-rise glucose stimulation.

The sensitized effect of prestimulation with 16.7 mM glucose on insulin release with a slow-rise glucose stimulation from the perifused rat islets of Langerhans was studied, together with the kinetic analysis of insulin release, and the interrelationship between the prestimulation time and the maximal rate of insulin release. All dose-response relationships which were derived from the dynamics of insulin release from islets prestimulated over various time periods within 60 min, showed sigmoidal profiles. Kinetic analyses were performed with Lineweaver-Burk's and Hill's equations. The 30-min prestimulation significantly reduced Hill's constant (n) from 6.2 +/- 0.7 of the control to 3.7 +/- 0.6 (p less than 0.05) and also enhanced the logarithmic equilibrium constant (log K) from -5.4 +/- 0.6 mM-n to -3.7 +/- 0.6 mM-n (p less than 0.05). However, the Km value was almost the same as that of the control (7.3 +/- 0.5 mM). On the other hand, the 60-min prestimulation remarkably diminished the Km value and the maximal rate of insulin release to 5.3 +/- 0.4 mM (p less than 0.05) and 0.6 +/- 0.08 muU/ml/islet/min (p less than 0.005), respectively. The maximal rate of insulin release linearly increased in proportion to the prestimulation time within 30 min. In conclusion, these results suggested that there would be some regularity depending on the prestimulation time in the process of transmission of the insulin-releasing signal in the pancreatic B cell and the accumulation of insulin into the provisional pool such as the labile insulin.

Animals↗