Prestin-dependent and prestin-independent motility of guinea pig outer hair cells

The motile response of isolated guinea pig outer hair cells (OHCs) was investigated using a combination of whole-cell patch clamp recording and continuous video image analysis. OHC's length, width, and area were measured from video images and the cell volume estimated from these values. Morphological data was then correlated with electrophysiological recordings of whole-cell current, membrane potential and voltage-dependent non-linear capacitance. Electromotility was evoked either by manipulating the membrane potential under voltage-clamp conditions or by exposing OHCs to high K+ solutions. Other motile responses were investigated in voltage-clamp experiments at constant holding potential, or exposing OHCs to solutions that did not affect the membrane potential. We found that electrical stimulation evoked voltage-dependent changes in OHC's length, width and area but not in cell volume regardless of the time course of stimulation. Moreover, changes in cell area were always associated with both voltage-dependent motility and non-linear capacitance, suggesting prestin dependency. In contrast, voltage-independent motile responses at constant membrane potential, which are presumed to be prestin-independent, were associated with changes in cell length, width and volume without significant changes in area. Area measurements, then, become a tool to investigate the simultaneous occurrence of both prestin-dependent and prestin-independent OHC motilities, and for evaluating the individual contribution of each mechanism to the total cell movement.     

Reduction of radiation dose at HRCT of the temporal bone in children

PURPOSE: The purpose of this study was to reduce the radiation exposure of the eye lens in high resolution computed tomography (HRCT) of the temporal bone using an experimental phantom. MATERIALS AND METHODS: The HRCT image that was used for analysis was obtained by changing parameters including effective-mAs (E-mAs), distance coverage, and height of object in the Y-axis. Radiation exposure was measured to calculate equivalent doses by glass rod dosimeters that were fixed above the right orbit parallel to the body axis. Deterioration in image quality was evaluated by three radiologists and the following three-point rating method was employed: grade 1 (good image quality without diagnostic limitations), grade 2 (image was deteriorated, but there were no diagnostic limitations), and grade 3 (image was deteriorated with diagnostic limitations). RESULTS: Assuming that the equivalent dose was y (mSv), and E-mAs was x, a simple regression line, y=0.506x-0.494 (decision coefficient, R2=0.999), was obtained. A standard deviation (S.D.) less than 120 (E-mAs, 220-120) was judged as grade 1, an S.D. between 120 and 150 was judged as grade 2, and an S.D. higher than 150 was judged as grade 3, indicating that deterioration of the quality of images with reduced E-mAs affected the diagnosis by imaging at S.D. higher than 150. CONCLUSION: Radiation dose at the eye lens in HRCT could be reduced up to an equivalent dose corresponding to 70 mAs without compromising diagnostic quality in the phantom experiment.     

The impact of angiogenesis on the prognosis of advanced renal cell carcinomas

We studied the relationship between angiogenic factors and clinical responses in advanced renal cell carcinomas (RCCs) and evaluated the angiogenic factors to clarify the potential impact of these factors on the cancer-specific survival. From January 1990 to December 2000, 148 patients underwent a nephrectomy for RCCs at our institution. Of the 32 patients who had distant metastasis, 17 met the histopathologic analysis requirements for an immuno-histochemical investigation. Fifteen of them were administered interferon-gamma and the remaining two patients were added to interferon-alpha and eight of seventeen patients also underwent radiation therapy. Both thymidine phosphorylase (TP) and Factor VIII immunostaining were performed. The overall survival rates at 1, 5 and 10 years were 82.4%, 30% and 30%, respectively. Three of these patients were diagnosed with lung metastasis and a complete response was seen in two, while a partial response was observed in one. In addition another patient who was diagnosed with bone metastasis also showed a partial response (group A). The remaining 13 patients showed progressive disease (group B). Group A had a higher TP-positive ratio (TP-PR) than that of group B. A multivariate analysis of the clinicopathologic data showed that a positive mean vascular area (PMVA) could be an independent factor regarding the potential impact of these factors on a long survival in advanced RCCS. PMVA was thus found to be an independent factor regarding the prognosis with advanced RCCs.     

Testicular abscess: report of 2 cases

We report two cases of testicular abscess. The first case is in a 53-year-old man who had been suffering from diabetes mellitus. Because of cerebral infarction, he had been bedridden and a Foley catheter had been indwelt for a long period of time. The second case is in a 78-year-old man who had suffered from acute prostatitis six months earlier. In both cases, the chief complaints were high fever and painful scrotal swelling. At initial evaluation, ultrasonography revealed that the affected testes were swollen without abscess formation and an ipsilateral epididymal swelling was demonstrated in the second case but not in the first case. The urine bacterial culture (UBC) result was positive for Escherichia coli in first case and Pseudomonas aeruginosa in the second case. In both cases, fever and scrotal pain subsided after antibiotic chemotherapy, and inflammatory reactions on routine blood studies were normalized within 2 weeks. Nevertheless, the swollen testes did not sigunificantly reduce in size, and testicular abscess was suspected by magnetic resonance imaging (MRI). Orchiectomy was performed, and intratesticular abscess formations were confirmed macroscopically and microscopically. In each case, bacterial culture from the abscess was positive for the same bacterium as detected from the UBC. It is difficult to distinguish testicular abscess from acute epididymitis at the early stage because of similarities on symptoms or signs between the two. If testicular swelling lasts after appropriate chemotherapy, we believe that attention should be directed to testicular abscess, which needs orchiectomy to obtain a complete cure and MRI is useful in its diagnosis.     

Treatment of traditional Chinese medicine for idiopathic male infertility

Several Chinese herbal medicines have been used to treat patients with idiopathic male infertility and have been reported to improve semen quality. The clinical efficacy of these medicines was reviewed. The therapeutic effect of Hochu-ekki-to based on the pretreatment traditional diagnosis (Sho) was examined. Three months after the administration of Hochu-ekki-to, the semen count and motility significantly increased in comparison with pretreatment values. When the patients were classified into 3 categories based on "Sho", Hochu-ekki-to was effective in semen motility in patients with vacuity pattern (Kyo-Sho). Seminal plasma soluble Fas (sFas) levels before and three months after the administration of drug were analyzed. Seminal plasma sFas level elevated significantly after the administration of Hochu-ekki-to. After the administration of Hochu-ekki-to, seminal plasma sFas levels significantly correlated with sperm concentration. To make the best use of traditional medicine, it is important to give medication according to the traditional diagnosis (Sho).     

Relationship between penile hemodynamic parameters assessed by color Doppler ultrasonography and penile rigidity recorded by the RigiScan Plus

OBJECTIVE: We studied the relationship between penile hemodynamic parameters assessed by color Doppler ultrasonography and penile rigidity estimated by objective measurement. PATIENTS AND METHODS: A total 37 patients with erectile dysfunction were examined. After intracavernous injection of 20 microg prostaglandin E1, we measured their penile hemodynamic parameters in the cavernous arteries by color Doppler ultrasonography. Simultaneously, the RigiScan Plus device was used for real-time evaluation of penile rigidity. Hemodynamic parameters were correlated with penile rigidity. RESULTS: Peak systolic velocity and resistive index were significantly correlated with penile tip (r = 0.54, r = 0.72, respectively) and base (r = 0.55, r = 0.76, respectively) rigidity; there was no significant correlation between end-diastolic velocity and penile rigidity. CONCLUSIONS: Peak systolic velocity and resistive index were strongly correlated with penile rigidity in patients with erectile dysfunction during intracavernous pharmacological testing. The resistive index in particular appeared to be the most valid parameter for assessment of penile rigidity.