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T Kurita

Publications and source records attributed to T Kurita.

At least 19 recordsLinked to original sources
PubMed1992

Frequency analysis of signal-averaged electrocardiogram in patients with right ventricular tachycardia.

OBJECTIVES: The purpose of this study was to analyze the frequency content of signal-averaged electrocardiograms (ECGs) in patients with idiopathic ventricular tachycardia of right ventricular origin and in patients with arrhythmogenic right ventricular dysplasia. BACKGROUND: The late potentials in the time domains are usually found in patients with arrhythmogenic right ventricular dysplasia. They are not usually found in patients with idiopathic ventricular tachycardia of right ventricular origin. METHODS: Fast Fourier transform analysis of signal-averaged ECGs was performed with the use of a Blackman-Harris window in 43 subjects: 20 normal volunteers (group I), 12 patients with idiopathic ventricular tachycardia of right ventricular origin (group II) and 11 patients with arrhythmogenic right ventricular dysplasia (group III), and the frequency spectrum was displayed in a three-dimensional graph. Area ratio (ratio of the area under the spectral plot from 40 to 120 Hz to the area from 0 to 120 Hz) was calculated in all subjects. RESULTS: Area ratio was significantly higher in group II than in group I (243 +/- 45 vs. 196 +/- 15, p < 0.01) and significantly higher in group III (396 +/- 51) than in group I or II (p < 0.001). The high frequency components in group II were confined within the QRS complex in the three-dimensional graph, whereas those in group III extended outside the QRS complex. CONCLUSIONS: Frequency analysis of the signal-averaged ECG with fast Fourier transform analysis can detect the high frequency components in patients with right ventricular tachycardia, including idiopathic ventricular tachycardia and arrhythmogenic right ventricular dysplasia.

Adult↗
PubMed1992

Molecular cloning and sequencing of cDNA encoding urinary stone protein, which is identical to osteopontin.

We have sequenced a cDNA of urinary stone protein. cDNA sequences show complete homology between urinary stone protein and human osteopontin (bone sialoprotein) (nucleotides 265-886 and 1183-1424). Osteopontin is a recently discovered bone matrix protein which has been implicated in mediating mineral formation within bone extracellular matrix. This result shows that osteopontin is presumably involved in stone formation as stone matrix.

Base Sequence↗
PubMed1992

Bradycardia-induced abnormal QT prolongation in patients with complete atrioventricular block with torsades de pointes.

Fourteen patients with complete atrioventricular block with or without torsades de pointes (TdP) were included in this study. They were divided into 2 groups, 6 patients with TdP (TdP[+] group) and 8 patients without TdP (TdP[-] group). The patients were evaluated at 2 different periods, before (acute period) and after (chronic period) pacemaker implantation. In the acute period, the QRS and heart rate during the escape rhythm were not significantly different between the 2 groups; however, the QT and QTc intervals were significantly longer in the TdP(+) group than in the TdP(-) group: 753 +/- 57.5 vs 635 +/- 78.4 ms (p less than 0.01) and 585 +/- 44.8 vs 476 +/- 58.3 ms (p less than 0.01). In the chronic period (greater than 2 months after pacemaker implantation), we changed the pacemaker rate from 90 or 100 beats/min to 50 beats/min and examined the QT interval changes in relation to the heart rate. The QT interval in the TdP(+) group was significantly prolonged compared with the TdP(-) group when the pacing rate was decreased less than or equal to 60 beats/min: 551 +/- 40 vs 503 +/- 36 ms at 60 beats/min (p less than 0.05), and 700 +/- 46 vs 529 +/- 43 ms at 50 beats/min (p less than 0.001). Patients with complete atrioventricular block with TdP had a bradycardia-sensitive repolarization abnormality and this characteristic remained after pacemaker implantation. The critical heart rate that induced abnormal QT prolongation in the TdP(+) group was less than or equal to 60 beats/min.

Adult↗
PubMed1992

Induction of TU abnormalities in patients with torsades de pointes.

1. TU abnormalities could be induced by the specific interventions in the majority of the patients with TDP in chronic stage: isoproterenol in congenital long QT patients, disopyramide in Ia-related TDP patients, and slow heart rate in bradycardia-related TDP patients. 2. Humps in MAP could be recorded in all patients with congenital long QT syndrome by isoproterenol, in half of the patients with Ia-related TDP by disopyramide, but in none of the control patients by these agents. 3. The results suggested that TU abnormalities and the occurrence of hump in MAP were hypersensitive reactions. 4. The results also suggested that specific intervention was not enough for the appearance of marked TU abnormalities in some TDP patients, especially in Ia-related TDP patients. Additional aggravating factors were probably required for marked TU abnormalities and the occurrence of TDP in these patients.

Action Potentials↗
PubMed1992

A new method for determination of urinary citrate.

We have developed a new assay technique using high-performance liquid chromatography. The assay was performed at a flow rate of 0.7 ml/min, a temperature of 60 degrees C and an ultraviolet absorption of 214 nm. Comparison of the results of the new assay with the results obtained for identical samples using the conventional fluorometric method demonstrated a very high correlation coefficient of 0.931.

Adult↗
PubMed1992

Clinical assessment of carcinoma in situ of the human urinary bladder.

Recent interest in intravesical instillation of bacillus Calmette-Guérin for the management of carcinoma in situ (CIS) of the bladder prompted us to review our results of total immediate cystourethrectomy. From 1975 to 1987, we surgically treated 302 patients with primary bladder tumours. Of these, 21 bladder tumours were histologically diagnosed as CIS, and total immediate cystourethrectomy was performed in all cases. The lesions were classified into three types: primary CIS accompanied by neither previous nor simultaneous tumours of the urinary tract (Type 1, 9 patients), concomitant CIS associated with superficial papillary tumour (Type 2, 6 patients), and secondary CIS detected during the follow-up period after treatment of the superficial papillary tumour (Type 3, 6 patients). Primary CIS was more often diagnosed according to subjective symptoms such as micturition pain than concomitant CIS. Secondary CIS was diagnosed in all patients by routine examinations including cytology and cystoscopy. There was no particular relationship between the time of recurrence of the tumour and the occurrence of secondary CIS. Within the same period, 60 patients with stage T1 bladder tumour were treated by total cystourethrectomy. The actuarial 5-year survival rate was 77% for T1 and 75% for CIS. The 5-year survival rate was 71% for Type 1, 83% for Type 2, and 67% for Type 3 CIS with no difference among the CIS types. Tumour invasion to the bladder, prostate, ureter, or lymph nodes was observed in 9 (42.9%) of the 21 patients, although cystourethrectomy was performed within 3 months of the diagnosis. Examination of ABH antigens did not allow prediction of invasion of CIS. Our findings suggest that the invasive potential of CIS may seriously limit the indications of conservative treatment against carcinoma in situ.

Adult↗
PubMed1992

Comparison of imaging methods for localization of parathyroid tumors.

Preoperative localization of parathyroid tumors by computed tomography (CT), thallium-201/technetium-99m pertechnetate subtraction scintigraphy (Tl-201/Tc-99m), ultrasonography (US), and magnetic resonance imaging (MRI) was compared in patients with hyperparathyroidism (HPT) to examine the characteristics of each method. A total of 87 patients with HPT were divided into two groups according to the time when they were examined. Patients in group I were examined before MRI had been introduced in our hospital, and a 2.5-MHz transducer probe was used for US. Those in group II were examined by MRI and US using a 7.5-MHz transducer probe. Group I included 45 patients (36 with primary hyperparathyroidism [PHPT] and 9 with secondary hyperparathyroidism [SHPT]), and group II included 42 patients (15 with PHPT and 27 with SHPT). In both PHPT and SHPT and SHPT of group I and PHPT of group II, there was no significant difference in detection rates between all diagnostic methods. In patients with SHPT in group II, the detection rate was significantly higher for CT than for Tl-201/Tc-99m and MRI (both p less than 0.01), and for US than for Tl-201/Tc-99m (p less than 0.01). In both groups I and II, the detection rate of each study method was significantly higher in patients with PHPT than in those with SHPT (all p less than 0.01). Compared with group I, the rate was significantly improved in group II, in both types of patients. Regarding the location of the parathyroid tumor, the detection rate of CT was significantly higher for upper parathyroid glands than for lower glands, whereas that of US and Tl-201/Tc-99m was significantly higher for lower glands. The detection rate sharply increased when the tumor weight reached 250 mg (CT, US) or 1,000 mg (Tl-201/Tc-99m, MRI).

Adult↗
PubMed1992

Clinical events in association with timing of intraventricular hemorrhage in preterm infants.

To ascertain whether any routine practices or clinical manipulations in a neonatal intensive care unit could induce intraventricular hemorrhage (IVH) in preterm infants, we performed ultrasonic monitoring of the germinal layer continuously for 48 hours in 33 extremely premature infants with respiratory distress. Intraventricular hemorrhage developed in 16 of these infants. In four infants the timing of the germinal layer hemorrhage was confirmed with ultrasonic monitoring. Three of the four cases were apparently associated with clinical events occurring at the moment of IVH: manual ventilation for improvement of hypercapnia associated with primary pulmonary hypertension of the newborn; correction of hyperkalemia, which was causing an arrhythmia, with administration of calcium gluconate and sodium bicarbonate; and administration of surfactant-TA to improve respiratory failure caused by pulmonary hemorrhage. In these three infants it appeared that one of the basic factors inducing IVH might be an increase in blood pressure with or without hypercapnia, causing cerebral reperfusion after ischemic damage of the germinal layer.

Blood Pressure↗
PubMed1992

Effects of a combination of disopyramide and mexiletine on the anterograde accessory pathway conduction in patients with Wolff-Parkinson-White syndrome.

In order to evaluate the electrophysiological effects of the combined administration of disopyramide and mexiletine on anterograde accessory pathway conduction, we studied 11 patients with Wolff-Parkinson-White (WPW) syndrome. Disopyramide was first infused intravenously at 1 mg kg-1 for 5 min followed by a continuous infusion at 0.025 mg kg-1 min-1. After the infusion rate of disopyramide was decreased to 0.004 mg kg-1 min-1 to maintain a lower serum concentration, mexiletine was infused at 2 mg kg-1 for 5 min followed by a continuous infusion at 0.008 mg kg-1 min-1 (protocol 1). The shortest atrial paced cycle length with 1:1 anterograde accessory pathway conduction (shortest CL with 1:1) and the anterograde effective refractory period of the accessory pathway (ERP) were measured: (1) before drug administration, (2) after disopyramide was given alone, and (3) after disopyramide and mexiletine were combined at lower concentrations. The same protocol was repeated with the order of drug administration reversed (mexiletine followed by disopyramide) in all patients (protocol 2). Both disopyramide and mexiletine lengthened the shortest CL with 1:1 and the ERP to the same degree. The combination of disopyramide and mexiletine at lower concentrations further lengthened the shortest CL with 1:1. It was longer than with disopyramide (protocol 1) or mexiletine (protocol 2) alone [protocol 1: 412 +/- 169 ms (combination) vs 356 +/- 117 ms (disopyramide); P less than 0.05, protocol 2: 409 +/- 166 ms (combination) vs 355 +/- 119 ms (mexiletine); P less than 0.01].(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Significance of ventricular pacing site in manifest entrainment during orthodromic atrioventricular reentrant tachycardia with left-sided accessory pathway.

We examined entrainment by ventricular pacing in six patients during orthodromic atrioventricular reentrant tachycardia (AVRT) utilizing a left-sided lateral accessory pathway. Constant fusion and progressive fusion were demonstrated in all patients by left ventricular pacing during tachycardia, but in none of the patients by right ventricular pacing. When left ventricular pacing was performed during AVRT, the antidromic wave front from the pacing impulse (n) collided with the orthodromic wave front of the previous pacing beat (n - 1) within the ventricle, therefore, constant fusion and progressive fusion were demonstrated in the surface electrocardiographic QRS complexes. On the other hand, when right ventricular pacing was performed during orthodromic AVRT, the antidromic wave front from the pacing impulse (n) collided with the orthodromic wave front of the previous paced beat (n - 1) within the normal atrioventricular pathway, and constant fusion and progressive fusion were therefore not demonstrated. These phenomena were explained by the relationship of the ventricular pacing site and the reentrant circuit. This study demonstrates the importance of the pacing site in manifest entrainment of orthodromic AVRT during ventricular pacing.

Adult↗
PubMed1992

Renal damages after extracorporeal shock wave lithotripsy evaluated by Gd-DTPA-enhanced dynamic magnetic resonance imaging.

Renal damages after extracorporeal shock wave lithotripsy (ESWL) were evaluated by magnetic resonance imaging (MRI) including Gd-DTPA-enhanced dynamic MRI in 37 patients with renal stone by spin echo methods (T1 and T2-weighted scan) and small tip angle gradient echo method (T2-weighted scan). Sixty-eight percent of the patients had changes in the MRI findings after ESWL. The frequently observed findings were perirenal fluid collection (38%), loss of corticomedullary junction (35%), and increased signal intensity of muscle and other adjacent tissue (34%). Preoperative Gd-DTPA-enhanced dynamic MRI showed low intensity band which suggests Gd-DTPA secretion from the glomerulus into the renal tubulus. In all cases the low intensity band became unclear after ESWL because of renal contusion due to ESWL. MRI, including Gd-DTPA-enhanced dynamic MRI, is considered to be a good procedure for evaluation of renal damages due to ESWL.

Contrast Media↗
PubMed1992

Spectral analysis of signal-averaged electrocardiograms in patients with idiopathic ventricular tachycardia of left ventricular origin.

BACKGROUND: The signal-averaged ECG has been used to detect late potentials, and it is considered a noninvasive marker for areas of slow conduction requisite for reentrant arrhythmia. Late potentials are not usually found in patients with idiopathic ventricular tachycardia (VT); nevertheless, fragmented electrograms are often recorded in those patients during endocardial mapping. The purpose of this study was to investigate the spectral content of the signal-averaged ECGs with use of fast Fourier transform analysis (FFT) in patients with idiopathic VT of left ventricular origin. METHODS AND RESULTS: Signal-averaged ECGs were recorded in 12 patients with idiopathic VT originating from the left ventricle (group 1) and 25 age-matched normal volunteers (group 2). Frequency analysis with FFT was performed with a Blackman-Harris window in a segment length of 120 msec from 40 msec before the end of the QRS complex, and the frequency spectrum was displayed in a three-dimensional graph. Area ratio 1 (area of 20-50 Hz/area of 10-50 Hz) and area ratio 2 (area of 40-100 Hz/area of 0-40 Hz) were calculated in all subjects. Late potentials defined by the time domain were negative in all subjects. The area ratios of group 1 were significantly higher than those of group 2. High-frequency components in the three-dimensional graph were confined within the QRS complex. CONCLUSIONS: These results suggest that frequency analysis of signal-averaged ECGs with FFT is an available method for detecting the high-frequency component within the QRS complex in some patients with idiopathic VT of left ventricular origin.

Adult↗
PubMed1992

[Study of factors requiring more than two ESWL treatments].

Nine hundred and fifty cases with renal and ureteral stones were treated by extracorporeal shock wave lithotripsy (ESWL) with Siements Lithostar unit from September, 1988 to October, 1990 at Kinki University Hospital. ESWL treatments were performed twice or more on 110 cases (DIFFICULTY GROUP). Ninety-seven cases who were cured by only one ESWL treatment were selected randomly as the control group. The two groups were retrospectively compared to study the factors requiring more than two times of ESWL treatments. There was a significant difference in the time of spontaneous stone discharge before ESWL treatment, the degree of hydronephrosis and the incidence of staghorn calculi as well as middle-lower ureteral calculi between the two groups. There was not a significant difference but a tendency to a longer period of stone existing at the same position and a higher percentage of past history of percutaneous nephrolithotropsy (PNL) in DIFFICULTY GROUP. Because ESWL monotherapy is considered to have limitations, auxiliary procedures or other treatments such as PNL and transurethral lithotripsy are recommended for patients in who in the stones were poorly disintegrated by the first ESWL treatment.

Humans↗
PubMed1992

[Investigation on unsuccessful endoscopic operation for cases with vesicoureteral reflux].

Endoscopic operation of vesicoureteral reflux (VUR) has several advantages such as less invasiveness and technical ease with the procedure and shorter hospitalization for the operation in comparison with coeliotomy, but the cure rate achieved by endoscopic operation compares unfavorably with that by coeliotomy. The unsuccessful cases of VUR by endoscopic operation were investigated to promote the success rate by endoscopic operation. Of 66 ureters in 55 patients 50 were successfully treated with the first operation, and 4 of 8 ureters with the second one. All 15 infants were cured, but the cure rate in females between 17 and 45 year old was significantly low (57%). An equally high cure rate was obtained by the endoscopic operation even in patients who had a high grade VUR, patulous ureteral orifices, an underlying neurogenic bladder, or episodes of urinary tract infection. All ureters were cured just after operation. The recurrence of VUR occurred in 19 ureters (29%) and 16 ureters were discovered at one month examination after operation, which indicates that olive oil dissolving teflon paste was partly absorbed to bladder tissue. Teflon paste shifted to internal urethral orifice in 4 unsuccessful ureters. Based on these findings, the endoscopic operation should be considered to be the preferred treatment among others in the management of VUR and the injection of sufficient volume of teflon paste into submucosal and muscular space of the bladder trigone could promote the cure rate.

Adolescent↗
PubMed1992

[Treatment of rejection with deoxyspergualin after renal transplantation].

Deoxyspergualin (DSG), which is a new immunosuppressive drug developed in Japan, is expected to be an immunosuppressant for the treatment of rejection, because it has immunosuppressive action different from that of other drugs. In the present study we used DSG to treat renal allograft rejection of in total 17 cases; 6 cases with acute rejection, 8 with chronic rejection and 3 with acute on chronic rejection. We infused DSG very slowly over 3 hours at a dose of 3-7 mg/kg/day for 5-7 days. Four cases (44.4%) with acute or acute on chronic rejection showed excellent response to DSG, three cases (33.3%) showed fair response and two cases (22.3%) did not respond at all. We also used DSG in patients with chronic rejection. In many of them, the increase in serum creatinine was suppressed. Ten of the total patients (58.8%) developed side effects including leukocytopenia, thrombocytopenia, numbness of the fact etc. No patients needed discontinuation of DSG. From the above results, we think that DSG is a safe and effective drug to treat acute rejection. Furthermore, we could get the results which suggest that DSG is effective for the treatment of chronic rejection.

Adolescent↗
PubMed1992

[A multicenter, fixed-flexible dose study of terazosin hydrochloride in the treatment of symptomatic benign prostatic hypertrophy].

In this study the multicenter, fixed-flexible dose regimen was taken to evaluate the effective dose range of Terazosin for the treatment of micturition disturbance in benign prostatic hypertrophy (BPH) and to clarify the characteristics of patients who are more responsive to Terazosin therapy. After a 1-week washout (placebo) the first two weeks 1 mg/day of Terazosin was administered, then depending on efficacy of subjective symptoms, Terazosin doses were increased up to 2 mg/day and 4 mg/day at intervals of two weeks. After six weeks the final efficacy and safety were assessed. The subjective symptom improvement rate was 18.5% by 1 mg/day, 55.6% by 2 mg/day and 65.4% by 4 mg/day cumulatively. The objective symptom improvement rate were 13.2% by 1 mg/day, 42.1% by 2 mg/day and 50.0% by 4 mg/day cumulatively. The global improvement rate was 14.5% by 1 mg/day, 50.0% by 2 mg/day and 61.8% by 4 mg/day cumulatively. The patients who had a higher subjective symptom score in the lead-in period were more improved rather than those who had a lower score. In objective symptoms, voided volume, maximum flow rate (MFR), MFR nomogram score and average flow rate improved and the ratio of residual urine volume decreased. There was no relationship between clinical improvement on either subjective or objective symptoms and prostatic weight. Adverse reactions, such as dizziness, vertigo, tinnitus, nausea and blurred vision; were seen in 10 cases. In conclusion Terazosin was effective and well tolerated for the treatment of patients who had micturition disturbance with BPH in the dose range of 2 to 4 mg/day.

Adrenergic alpha-Antagonists↗