Muscle sympathetic nerve activity during central,mixed and obstructive apnea: Are there any differences?

Abstract  We recorded muscle sympathetic nerve activity (MSNA) from the peroneal nerve during sleep in three OSAS patients who showed three kinds of apnea. During central apneas and central component of mixed apnea, bursts of MSNA appeared in high probability with almost each heart beat. During obstructive apneas and the obstructive component of mixed apneas, bursts of MSNA appeared in a cluster after the end of each inspiratory effort. Burst rate of MSNA during apnea were higher in central apneas and the central component of mixed apnea than in obstructive apneas and the obstructive component of mixed apneas. These findings indicate that activity in the sympathetic nervous system is enhanced not only in obstructive apnea but also in central and mixed apnea.     

Treatment of Malignant Neurocardiogenic Vasovagal Syncope with a Rate Drop Algorithm in Dual Chamber Cardiac Pacing

A 29-year-old man with malignant vasovagal syncope presented with episodes of abrupt loss of consciousness associated with an aura, totaling more than 10 episodes over 3 months. Holter monitoring showed cardiac arrest with a duration of 15 seconds. Oral propranolol and disopyramide therapy failed to prevent the syncope. A dual chamber pacemaker with a rate drop response algorithm successfully prevented the syncope but not the aura. There may be multifactors involved in the mechanism of this syndrome. The patient has returned to a normal active life. This rate drop algorithm is an effective therapy for the prevention of syncope in malignant vasovagal syncope.     

Ultrasonic Tactile Sensor: An Experimental Study to Evaluate the Depth of Invasion in Esophageal Squamous Cell Carcinomas

Abstract: To date, an objective scale for evaluation of tissue stiffness has been lacking. A new instrument, the “ultrasonic tactile sensor (UTS)”, allows objective evaluation of stiffness. For the purpose of evaluating cancer stiffness, we first introduce an experimental study on tissue stiffness using surgically resected specimens of esophageal squamous cell carcinomas with no special preoperative treatment. From November 1995 to January 1996, the authors examined 11 esophageal cancer specimens. Although this experiment revealed no differences between normal mucosa and mucosal cancer in the esophagus, significant differences between mucosal and submucosal cancers in terms of tissue stiffness were clearly demonstrated. Therefore, UTS examination is useful for assessing malignant invasion, thereby providing valuable information for determining appropriate indications for endoscopic mucosal resection. We currently perform this UTS examination using a miniature probe during preoperative endoscopy. We anticipate that this new method will become an essential tool for evaluating the depth of invasion in esophageal cancer preoperatively.     

Absorbable and Sell-expanding Esophageal Stent

Abstract: A flexible self-expanding esophageal stent, made entirely of absorbable materials, was recently developed by the authors. The new stent consists of two components: a rolled vicryl sheet (Vicryl woven mesh, Ethicon) which has a 20-mm outer diameter, and a PDS string (PDS II, 1 -0. Ethicon) which runs spirally around the rolled sheet. The stent is almost equal in flexibility to the Ultraflex (Microvasive, USA) and its expanding force exceeds that of the Ultraflex. This stent was uneventfully placed in the porcine esophagus and then fully opened. This absorbable stent, incubated in 37°C saline, showed a gradual diminution of its expanding force over a period of more than two weeks. We conclude that this novel absorbable stent, which has characteristics comparable to those of a metallic stent, as well as certain other advantages, is applicable to clinical cases.     

Prevalence of sleep-related respiratory disorders in 101 schizophrenic inpatients

Abstract We studied the prevalence of sleep-related respiratory disorders (SRRD) in 101 schizophrenic inpatients (64 men and 37 women) and in 48 healthy volunteers (control group:22 men and 26 women) using ambulatory pulse-oximetric devices. Those with a desaturation index (DI) 5 were classified as having SRRD. The prevalence of SRRD in the schizophrenic patients (men 21.9%, women 13.5%) was not higher than that in the control group (men 30.7%, women 13.6%). Gender difference in the prevalence of SRRD was not observed in schizophrenic group. This was probably because the schizophrenic women took an increased amount of sleeping pills. Neuroleptics were shown to be least effected on SRRD.     

Functional evaluation of one-stage urethroplasty with parameatal foreskin flaps repair of hypospadias using uroflowmetry

BACKGROUND: Uroflowmetry is a simple, accurate and non-invasive test. In the present study, we aimed to determine the role of uroflowmetry in the evaluation of the functional results of one-stage urethroplasty with parameatal foreskin flaps (OUPF) technique. METHODS: Twenty-one children who had undergone OUPF repair at our clinic were selected. Selection criteria were that patients were toilet trained and had no fistula. Uroflowmetry was performed using a rotating disk sensor. The maximum flow rate (Qmax) and average flow rate (Qave) were plotted against body surface related flow rate nomograms. The upper 95% tolerance limits for the 5th, 10th, 15th, 20th and 25th percentiles of the normal population were used for comparison. The flow pattern was classified as bell ring, plateau or intermittent. RESULTS: The median age at the first uroflowmetry was 4.7 years (range 2.5-8.6) and the mean postoperative follow-up period was 25 months (range 1-58). Twelve children had Qmax above the 25th, six between the 5th and 25th and three less than the 5th percentiles of the normal population. A normal bell-shaped flow curve was obtained in 17 (80.6%) of the children. Of the three children with Qmax below the 5th percentile, two children had a plateau flow pattern and were found to have a urethal stricture. Dilation was performed successfully, after which the Qmax returned to the normal range and the symptoms disappeared. CONCLUSION: The OUPF technique provided satisfactory functional results for hypospadias repair. We advocate the use of uroflowmetry for routine postoperative follow-up.     

Acquired pure red cell aplasia in a hemodialyzed patient

A 68-year-old male had end-stage renal disease secondary to hypertension. He was placed on chronic dialytic therapy and was given recombinant human erythropoietin (epoetin) for renal anemia. One month later, rapidly progressing anemia was noted. The anemia was unresponsive to maximal doses of epoetin and the patient soon became transfusion-dependent. Erythroid hypoplasia was demonstrated by bone marrow biopsy. A detailed search for the cause of the erythroblastopenia revealed nothing. A diagnosis of acquired pure red cell aplasia was made. The use of immunosuppressive agents improved the patient's symptoms and laboratory data. Antibodies for erythropoietin (EPO) were negative after the treatment. It is suggested that patients with EPO-resistant anemia with no obvious etiology should be examined for underlying hematologic disorders.     

Effects of Thyrotrophin-releasing Hormone Tartrate and its Sustained Release Formulation on Cerebral Glucose Metabolism in Aged Rats

The effects of a sustained release formulation of thyrotrophin-releasing hormone (TRH) over two weeks (TRH-SR, 10 or 50 mg kg^? equivalent to 0.56 or 2.80 mg kg^? free TRH, respectively) and repeated treatment with TRH tartrate (TRH-T, 0.3, 1.0 or 3.0 mg kg^?, equivalent to 0.2, 0.7 or 2.0 mg kg^? free TRH, respectively) on the rate of local cerebral glucose utilization (LCGU) were investigated using the quantitative autoradiographic 2-deoxy-[¹⁴C]d -glucose method in various brain regions of aged rats. In aged rats (28 months old), the LCGU was significantly reduced as compared with young adult rats (3 months old), while treatment with TRH-SR ameliorated the reduction of the LCGU in a dose-dependent manner. The brain regions ameliorated by TRH-SR were the auditory cortex, septal nucleus, substantia nigra, cerebellar cortex and cerebellar nucleus. In contrast, once-daily repeated treatment over one week with TRH-T at a dose of 0.3 mg kg^? (equivalent to 50 mg kg^? of TRH-SR) had no effect on the reduced LCGU in various brain regions in aged rats (27 months old), whereas treatment with a higher dose of TRH-T (0.7 or 2.0 mg kg^? free TRH) significantly ameliorated the reduction. The comparison of the ameliorating potencies between TRH-T and TRH-SR indicated that TRH-SR had a potency about 7 times greater than TRH-T.