Biomedical subjects

A Kawauchi

Publications and source records attributed to A Kawauchi.

At least 37 records · Page 2Linked to original sources

PubMed1999

Firing of putative cholinergic neurons and micturition center neurons in the rat laterodorsal tegmentum during distention and contraction of urinary bladder.

The relation between unit activity in the laterodorsal tegmental (LDT) area and the state of the urinary bladder was examined in urethane-anesthetized rats. Neurons in the LDT area can be classified into two populations: broad-spike (possibly cholinergic) and brief-spike (non-cholinergic). When the rats showed cortical electroencephalographic activity with large amplitude lower frequency, indicative of deep anesthesia, more than 40% of the broad-spike neurons was excited and about 10% was inhibited by infusion of saline into the bladder. The response was followed by decrease in amplitude and slight increase in frequency of the cortical activity, i.e., lightening of anesthesia. During light anesthesia, excitation was observed only in less than 10% of the units, while 17% was inhibited. In the brief-spike neurons, a similar proportion (about 20%) was excited and less than 10% was inhibited by the distention during either state of anesthesia. About 10% of the broad-spike neurons in the LDT area and 30% of the brief-spike neurons examined were discharged prior to the bladder contraction. Such neurons of the brief-spike category were encountered frequently outside of the central gray; lateral, caudal and ventral to the main mass of cholinergic neurons in the LDT area. These results suggest the possible involvement of the broad-spike (cholinergic) neurons in the elevation of vigilance level caused by bladder distention. The brief-spike (non-cholinergic) neurons firing with relation to bladder contraction may be part of the micturition reflex center.

Action Potentials↗

PubMed1999

Systematic treatment for nocturnal urinary frequency following a sleep-micturition chart.

Seven patients complaining of nocturnal urinary frequency were treated following a sleep-micturition chart. By clinical analysis of the data, the causes of nocturnal urinary frequency were divided into three diagnostic categories: a small bladder capacity group, a sleep disorder group and a large nocturnal urinary volume group. The three groups were treated by anticholinergic agents, sleeping pills and restriction of water intake at night respectively. With the administration of anti-cholinergic agents or sleeping pills nocturnal bladder capacity increased. By restriction of water intake at night nocturnal urinary volume decreased. In all patients nocturnal urinary frequency decreased and sleep efficiency was improved.

Aged↗

PubMed1999

Locus coeruleus function in enuresis.

There are four neuronal networks projecting to many areas of the brain. All networks relate closely to arousal and sleep function. Among the four networks, the noradrenaline projection network, originating from the locus coeruleus (LC), is the system most typically responsible for arousal. This study shows that the LC is activated by the stimulation of bladder distension only while the patient is in deep sleep, not in light sleep. This finding corresponds with the mechanism of enuresis type I in our classification of enuresis, based on overnight simultaneous monitoring using electroencephalography and cystometry. The importance of arousal and sleep systems in the pathogenesis of enuresis is also discussed.

Arousal↗

PubMed1999

[Renal angiomyolipoma with marked extrarenal development: a case report].

A 28-year-old female complained of minimal fever elevation. Computed tomography (CT) revealed a left renal tumor of 10 cm in diameter. Ultrasonogram and CT, magnetic resonance imaging and angiography suggested a renal angiomyolipoma (AML) with marked extrarenal development. Partial nephrectomy was performed using a microwave tissue coagulater without clamping of the renal artery. The tumor weight was 800 g and the pathological diagnosis was AML. The management of large AML is reviewed in the literature. Nephron sparing surgery should be performed even in patients who have a larger tumor with extrarenal development.

Adult↗

PubMed1998

Changes in the structure of sleep spindles and delta waves on electroencephalography in patients with nocturnal enuresis.

OBJECTIVE: To evaluate the mechanism of the dysfunction of arousal in patients with Type I and Type IIa enuresis. PATIENTS AND METHODS: The numbers of sleep spindles and delta waves were analysed during electroencephalography in 19 patients with enuresis (17 male, two female, mean age 9.7 years, range 8-14). RESULTS: In four patients with Type I enuresis, who awoke spontaneously and remained dry as a result of urinary sensation, the numbers of sleep spindles and delta waves diminished gradually and finally disappeared just before the patients awoke completely. In the remaining nine patients with Type I enuresis, there was no decrease in the number of sleep spindles and delta waves, and enuresis occurred without the subjects awakening. In the six patients with Type IIa enuresis, there was no arousal reaction or generation of sleep spindles on urination while asleep. CONCLUSIONS: An immaturity in the function of the thalamus might be a cause of the arousal dysfunction in patients with Type I enuresis. In Type IIa enuresis, a possible abnormal or immature arousal mechanism in the pons or the lower tract may be responsible.

Adolescent↗

PubMed1998

The objective assessment of urinary incontinence in children.

OBJECTIVE: To assess urinary incontinence objectively in children. PATIENTS AND METHODS: Thirty-three children (mean age 8.2 years, range 5-12) were examined, of whom 23 suffered from incontinence and 10 did not. The first method of assessing incontinence was the 1-h pad-weighing test proposed by the International Continence Society in 1983 and the second was a test in which the pad was weighed between one urination and the next. At the end of the tests the volume of normally voided urine was measured and the total voided volume during the test calculated. The volume of urine lost during incontinence and the ratio [incontinence volume/(incontinence volume + voided volume)] were evaluated; the ratio was used because the bladder capacity in children differed with age. RESULTS: In both tests, no wetting occurred in any of the 10 patients not complaining of incontinence. In the 1-h pad-weighing test, no wetting occurred in 14 of the 23 patients complaining of incontinence but did in the nine remaining patients, the loss being 1-30 g, and the incontinence ratio 0.5-14.8%. In the second test, no wetting occurred in 12 of the 23 patients complaining of incontinence but did so in the 11 remaining patients, with losses of 2-50 g and incontinence ratios of 1.5-80.6%. CONCLUSIONS: There was no significant difference between the tests in the incidence of incontinence. However, the second method seemed to be more closely related to the clinical symptoms than was the 1-h pad-weighing test and may be useful in the assessment of incontinence in children.

Child↗

PubMed1998

How does the distention of urinary bladder cause arousal?

Under urethane anesthesia, the urinary bladder of male rats was distended by 0.3-0.5 mL of saline. When the animals displayed large amplitude delta waves, the distention caused tonic excitation in 76% (19/25) of the noradrenergic neurons in the locus coeruleus and in 53% (16/30) of the cholinergic neurons in the laterodorsaltegmental nucleus. The response was followed by a shift of electroencephalogram (EEG) pattern to faster waves of smaller amplitude. When EEG amplitude was faster and smaller, the same stimuli caused no response. Neurons in Barrington's nucleus were excited by a small amount of bladder distention independent of EEG patterns. These results suggest that the transition of state, caused by bladder distention, from deep sleep to light sleep is mediated by noradrenergic and cholinergic neurons in the brainstem.

Adrenergic Fibers↗

PubMed1998

Relationship between nocturnal urinary frequency and sleep disturbances in aged men.

The relationship between nocturnal urinary frequency and sleep disturbances is investigated in aged men in 12 rural towns in Kyoto and Shiga Prefectures. The subjects were 178 men who did not have diseases or symptoms that were likely to affect urinary condition or sleep. There were no significant differences in sleep disturbances, except sleep maintenance, between the normal group (nocturnal urinary frequency below twice per night) and the abnormal group (nocturnal urinary frequency twice or more per night). In healthy aged men, nocturnal urinary frequency only caused disturbance in sleep maintenance, but did not cause any other sleep disturbance.

Age Factors↗

PubMed1998

Classification based on overnight simultaneous monitoring by electroencephalography and cystometry.

OBJECTIVES: To evaluate the features of the clinical findings in three types (types I, IIa, IIb) of enuresis, classified by overnight simultaneous monitoring by electroencephalography (EEG) and cystometry (CM). METHODS: We performed a test to evaluate bladder capacity, arousal response and the pattern of nighttime urination in sucklings and infants. RESULTS: As for the values of enuretic bladder capacity (EBC), the smallest were found in enuresis type IIb. As for arousal response, enuresis type I showed the best, while enuresis type IIa showed the worst response. With regard to the pattern of nighttime urination in sucklings and infants, all sucklings had a stable bladder in the sleep state and urinated in the pattern of type IIa. The arousal response to bladder distention indicating type I appeared at the age of about 2 or 3. CONCLUSIONS: The smallest EBC in patients with enuresis type IIb represented a bladder dysfunction in the sleep period. It was observed that patients with enuresis type I had the best arousal function while those with enuresis type IIa had the worst arousal function. All sucklings urinated unconsciously during sleep in the pattern of type IIa. The arousal response to bladder distention indicating type I, which was not observed below the age of 1 year, was thought to appear at the age of about 2 or 3 years. If this change has not appeared by the age of 3, bed-wetting might persist after the age of 5.

Child, Preschool↗

PubMed1998

Effects of systematic treatment based on overnight simultaneous monitoring of electroencephalography and cystometry.

OBJECTIVE: To clarify the effects of systematic treatment based on overnight simultaneous monitoring by electroencephalography (EEG) and cystometry (CM) on each type of enuresis. METHODS: For enuresis type I, the change in the awakening response during the conditioning treatment with a therapeutic machine was observed. For enuresis type IIa, the effect of imipramine on the EEG was observed. For enuresis type IIb, the effect of oxybutynin hydrochloride on the cystometrogram (CMG) was observed. RESULTS: Values, in which the awakening score on the second night was subtracted from the score on the last night, were significantly higher in the effective cases than in the unchanged cases. Out of the 3 patients in whom imipramine was effective, an awakening response on the EEG was observed in 2. Neither of the 2 unchanged cases showed an awakening response. Out of 4 patients in whom oxybutynin hydrochloride was effective, uninhibited contractions (UIC) on the CMG disappeared in 3. UIC stopped in neither of the 2 unchanged cases. CONCLUSIONS: Improvement of the awakening response plays an important role in the effectiveness of conditioning treatment with our therapeutic machine. The generation of awakening response is thought to be the most important result of imipramine directly concerned with its clinical effect on enuresis type IIa. The main result with oxybutynin hydrochloride in enuresis type IIb is thought to be related to its antispasmodic effect.

Adrenergic Uptake Inhibitors↗

PubMed1998

[New application of ultrasound imaging using contrast agent].

Recently, various ultrasound contrast agent have been developed all over the world. This paper reviewed recent development of some contrast agent and clinical application of new imaging using contrast agent (Enhanced color Doppler Imaging, Harmonic Imaging, Flash Echo Imaging and Loss of Correlation Imaging). These new methods are easily feasible with a clinical ultrasound diagnosis machine for evaluating further information, for example, slow or deeply located lesion's blood flow, furthermore tissue perfusion. Contrast enhanced ultrasound imaging such as Harmonic imaging is enable to evaluate tissue function.

Animals↗

PubMed1998

[Evaluation of blood flows inside hepatic tumors using color Doppler echography with galactose-based intravenous contrast medium "SH/TA 508" administration].

The purpose of this study is to evaluate hemodynamic characteristics of various hepatic tumors using color Doppler echography administered galactose-based intravenous contrast medium "SH/TA 508 (Levovist)". Subject were 9 cases of hepatocellular carcinomas, 5 cases of metastatic liver tumors and a case of hemangioma. We evaluated the characteristics of blood flows inside various hepatic tumors, and also evaluated the first pass through the hepatic tumors during administration of Levovist. The strongly pulsatile branched blood flows inside tumor and the slow-increased and plateau patterns were observed in the all cases of hepatocellular carcinomas, the weakly pulsatile blood flows surrounding tumor and the rapid-increased and slow-decreased patterns were observed in the cases of metastatic liver tumors, and the continuous blood streams in the margin of tumor and the slow-increased and slow-decreased pattern were observed in the case of hemangioma. These findings were characteristic in various hepatic tumors, and color Doppler echography enhanced by Levovist was very useful to distinguish hepatic tumors.

Carcinoma, Hepatocellular↗

PubMed1998

[Contrast echo imaging on the breast and thyroid cancers].

The utility of ultrasound color Doppler flow mapping imaging for the differential diagnosis on the breast and thyroid tumors had already reported in 1991. Ultrasound contrast agent, SH/TA 508 (Levovist; Schering AG, Germany), had already finished clinical trials in Japan and reported the result phase II, III. On the breast and thyroid lesions, the utility of this contrast agent are safety and usefulness for the accurate diagnosis by the ultrasound color Doppler examination. Throughout of these clinical trials, a quit new ultrasound Doppler imaging methods had been developed, Harmonic Imaging and acoustic emission mode. As the result, ultrasound contrast agent is useful not only for the conventional color Doppler diagnosis but also for the developing of new diagnostic imaging methods.

Breast Neoplasms↗

PubMed1998

Noninvasive evaluation of bladder compliance in children using ultrasound estimated bladder weight.

PURPOSE: In healthy children as well as those with urinary disturbance we determined ultrasound estimated bladder weight with the aim of revealing its possible usefulness as a measure of bladder compliance. MATERIALS AND METHODS: We measured ultrasound estimated bladder weight in 71 healthy children with a mean age of 10.3 years, and determined a standard value. A total of 82 patients with a mean age of 9.6 years with urinary disturbance also underwent ultrasound estimated bladder weight measurement as well as conventional urological examinations, including filling cystometry. RESULTS: In healthy children ultrasound estimated bladder weight increased with age, showing a significant linear correlation (r = 0.80, p < 0.0001). Using the formula for linear correlation, 0.86 x patient age + 6.9 gm., we obtained an age matched estimated weight. In 82 patients the percent deviation of the estimate from age matched values was calculated using the formula, (measured ultrasound estimated bladder weight -age matched ultrasound estimated bladder weight)/age matched ultrasound estimated bladder weight x 100, and then correlated with bladder compliance. In 75 of 77 patients (97%) with compliance of 10 ml./cm. water or more the estimate was within 100% deviation. In contrast, 4 of 5 patients (80%) with a low compliant bladder (less than 10 ml./cm. water) had an ultrasound estimated bladder weight greater than 100% deviation. When the estimate was within 100% deviation, all but 1 patient (75 of 76, 98.7%) had compliance of 10 ml./cm. water or more compared to 33.3% (2 of 6) of those with an estimate greater than 100% deviation. As a result, with the use of a cutoff value of 100% deviation ultrasound estimated bladder weight predicted a low compliant bladder with a diagnostic accuracy as high as 96.3% (79 of 82 cases). CONCLUSIONS: Ultrasound estimated bladder weight may be used to evaluate bladder compliance in children. It seems to be a suitable noninvasive urodynamic test in children with suspected urodynamic abnormalities.

Adolescent↗

PubMed1997

Physiological background of enuresis type I. A preliminary report.

The physiological background of enuresis Type I, which is due to a mild arousal dysfunction, has been investigated in two studies, one in rats and one in children with Type I enuresis. The results of these investigations suggest that in this type of enuresis, the fundamental arousal function following bladder distension, due to an arousal centre like the locus coeruleus and its network, is normal. In contrast, the process of multiplying the transient connection from light sleep to complete awakening, which probably relies upon functions of the thalamus and the further upper centrums, was thought to be abnormal.

Animals↗

PubMed1996

Early morning urine osmolality in nonenuretic and enuretic children.

Early morning urine osmolality in 1,453 nonenuretic children and 144 enuretic children was measured in a population study. Early morning urine osmolality was lower in nonenuretic children aged 3-4 years than in those aged over 5 years. A similar pattern was observed in enuretic children. No significant difference in early morning urine osmolality was observed between nonenuretic children and enuretic children at any age. These data suggest that nocturnal urine concentration may be immature in nonenuretic children under 4 years. We did not find any evidence for increased nocturnal urine production as a cause of enuresis.

Aging↗

PubMed1996

[Long-term results of systematic treatment for nocturnal enuresis based on overnight simultaneous monitoring of electroencephalography and cystometry].

BACKGROUND: The long-term results of systematic treatment based on overnight simultaneous monitoring of electroencephalography (EEG) and cystometry in the patients with enuresis were evaluated. METHODS: From January to December a total of 213 patients were classified into 3 types. Enuresis Type I: such cases show a normal cystometrogram (CMG) with an awakening response on the EEG before enuresis, but they do not awake. Enuresis Type IIa; such cases show a normal CMG without an awakening response on the EEG. Enuresis Type IIb: such cases show an abnormal CMG with no awakening response on the EEG. When such cases enter the deep sleep stage, continuous uninhibited contractions of the bladder are observed on the CMG. 136 cases were of Type I, 20 cases of Type IIa, and 57 cases of Type IIb. RESULTS: Out of 213 patients who were followed up for 2 years, cured cases were 94 (44%), effective cases were 81 (38%) and unchanged cases were 38 (18%). In 136 patients with Type I, cured cases were 71 (52%), effective cases were 50 (37%) and unchanged cases were 15 (11%). In 20 patients with Type IIa, cured cases were 8 (40%), effective cases were 9 (45%) and unchanged cases were 3 (15%). In 57 patients with Type IIb, cured cases were 15 (26%), effective cases were 22 (39%) and unchanged cases were 20 (35%). The age of the effective group, which included cured cases and effective cases, was significantly higher than that of the unchanged group. In enuresis Type I, the percentage of the patients with incontinence in daytime were significantly in the unchanged group than in the effective group. No significant differences in the frequency of enuresis and the percentage of the patients who had awakened spontaneously by urinary sensation were found between the two groups. CONCLUSION: The therapeutic response was best in enuresis Type 1 and worst in enuresis Type IIb. The patients, in whom not only frequency of enuresis but also type of enuresis was unchanged by systematic treatment for two years, was approximately 10% across the types. Accordingly they were thought to be non-responders to this systematic treatment.

Child↗

PubMed1996

Urological abnormalities in 1,328 patients with nocturnal enuresis.

OBJECTIVES: Evaluation of the incidence of urological abnormalities as revealed by urological examinations of a large number of patients with enuresis. METHODS: Patients with the chief complaint of nocturnal enuresis were examined urologically. RESULTS: The incidence of urological abnormalities was 1.8% of 940 patients on intravenous pyelography (IVP), 7.1% of 695 patients on voiding cystourethrography (VCG) and 11.5% of 487 patients on cystometry (CM). No abnormal findings were observed in 58 patients on renal ultrasonography (US). 92.1% of reflux cases detected by VCG were low grade and only 8.9% of patients with reflux had pyuria. 20.2% of 446 patients who were submitted to all these examinations had some urological abnormality. Only pollakisuria was statistically more frequent in patients with urological abnormalities than in patients without them. CONCLUSION: These data suggest that the incidence of urological abnormalities was rather low when compared with the past literature. In particular, IVP was though to be unnecessary.

Child↗