Extremely small-diameter, high-density, radio frequency, plasma sources and central gas feeding for next-generation electrodeless plasma thrusters.

Radio frequency (RF) waves including helicon waves can readily produce high-electron-density (ne up to 1013 cm-3) plasmas with a broad range of external operating parameters. Various featured RF and helicon sources in a wide range of scales are suitable for plasma propulsion schemes. Electrodeless RF plasmas have no direct contact between electrodes and antennas, which enables long-life operation. However, one of the crucial problems is to reduce the plasma size for future applications in nano- and pico-satellites. Diagnostics of the plasma parameters in a small area should also be improved. Furthermore, to increase plasma performance, it is important to consider the radial electron density (ne) profile with an increasing upper limit, observed in high-density helicon sources due to the depletion of neutrals. This problem may be controlled by the location of neutral gas feeding and knowledge of the gas pressure distribution. Here, production of RF plasmas, with extremely small diameters from 3-mm down to 0.5-mm including 1-mm, was demonstrated, and characterization of ne and the electron temperature was performed with a collisional radiative model. Finally, to improve plasma performance such as ne and the thrust force, internal gas feeding was demonstrated using a developed Pirani gauge to measure neutral density.

Autophagy regulates selective HMGB1 release in tumor cells that are destined to die.

Macroautophagy (hereafter referred to as autophagy) can increase or decrease the amount of cell death in response to various stimuli. To test whether autophagy also controls the characteristics associated with dying cells, we studied tumor cell killing by epidermal growth factor receptor-targeted diphtheria toxin (DT-EGF). DT-EGF kills epithelial and glioblastoma tumor cells with similar efficiency but by different mechanisms that depend on whether the cells activate autophagy when treated with the drug. Dying cells in which autophagy is induced selectively release the immune modulator high-mobility group B1 (HMGB1) without causing lysis of the cell membrane and classical necrosis. Conversely, cells that are killed by DT-EGF where autophagy is blocked, activate caspases but retain HMGB1. These data suggest that it may be feasible to manipulate the immunogenicity of dying cells by increasing or decreasing autophagy.

Coaxial-slot antenna for interstitial microwave thermal therapy and its application to clinical trial.

The authors have been studying thin coaxial-slot antennas for interstitial microwave thermal therapy. In this paper, firstly, the structure of the coaxial-slot antenna is briefly reviewed. Secondly, the procedure for temperature calculation around the antennas and the calculation model based on the CT images of the patient are described. Thirdly, the blood flow rate of the tissue concerned during the treatment is estimated from the temperature transition during the treatment. Finally, the temperature distribution in and around the tumor is calculated based on the estimated blood flow rate and some conditions for the actual treatment.

Serotonin-induced nitric oxide production in the ventral nerve cord of the earthworm, Eisenia fetida.

Effect of serotonin on nitric oxide (NO) production in the ventral nerve cord (VNC) of the earthworm Eisenia fetida was investigated by a bio-imaging and an electrochemical technique. In the bio-imaging, the spatial pattern of NO production in VNC was visualized using an NO-specific fluorescent dye, diaminofluorescein-2 diacethyl (DAF-2 DA). Application of serotonin (100 microM) increased NO production in VNC by about 65% (P<0.05), compared with basal NO production. The increase was mainly from the nitergic neurons in the ventral side of VNC. In the electrochemical technique, real-time basal and serotonin-induced NO production was estimated with an NO-specific electrode. On the ventral surface of VNC, the estimated basal NO production was stable at 200+/-52 nM, and was transiently augmented to 840+/-193 nM by the addition of 10 microM serotonin. In conclusion, the estimated basal NO production in the earthworm VNC is relatively high compared with other nervous systems earlier reported, and transiently augmented by serotonin. Our results suggest that NO signaling in VNC is involved in neuromodulation by serotonin.

Epileptic seizures and sleep-wake rhythm.

The subjects were 25 children, including West syndrome, Lennox-Gastaut syndrome, childhood absence epilepsy (CAE) and localization-related epilepsies. Clinical seizures occurred only during waking state in 14 patients (including the cases of West syndrome, CAE and epilepsy with myoclonic absences (EMA)), only during sleeping state (especially during non-REM sleep in five patients, including the case of benign epilepsy with centrotemporal spike), and diffusely during waking and sleeping states in six patients (including the case of early infantile epileptic encephalopathy with suppression burst). These three types were observed in the cases of Lennox-Gastaut syndrome and localization-related epilepsies. Subclinical ictal discharges occurred during REM sleep in West syndrome, and during REM and non-REM sleep especially during non-REM sleep in CAE and EMA.

Visualization of nitric oxide production in the earthworm ventral nerve cord.

Distribution of nitric oxide (NO)-producible neurons in the ventral nerve cord (VNC) of the earthworm was investigated by nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemistry. Some neurons (20-30 microm in diameter) were intensely stained and were localized in areas between the 1st and 2nd lateral nerves in the ventral side of VNC. In contrast, no neurons including giant fibers were stained in the dorsal side. Endogenous NO production from VNC was visualized using a fluorescent dye, diaminofluorescein-2 diacethyl (DAF-2 DA). When VNC was incubated in a saline, a relative high level of NO was produced from the ventral side, especially from NADPH-d-positive neurons. Under high-K+ stimulation, NO was also detected in the giant fibers in the dorsal side of VNC. Our results suggest that the earthworm VNC constantly and relative highly produces NO as a neuromodulator, and that NO produced from the ventral side sometimes reaches and affects the giant fibers. In conclusion, we successfully visualized NO in the earthworm VNC by clarifying both the distribution of NO-producible neurons and the endogenous NO production.

Recovery of sexual function after nerve-sparing radical prostatectomy or cystectomy.

BACKGROUND: The recovery of sexual function (erectile function and frequency of sexual intercourse) over time after nerve-sparing radical prostatectomy or cystoprostatectomy was evaluated. METHODS: Forty-nine consecutive patients with clinically localized prostate cancer and muscle-invasive bladder cancer were treated with radical prostatectomy and radical cystoprostatectomy with a nerve-sparing procedure. Erectile function was evaluated by the circumferential change of the penis during nocturnal penile tumescence (NPT value) with an erectometer before and after surgery. Erectile function and the frequency of sexual intercourse were also evaluated with a self-administered questionnaire before and after surgery. Multivariate analysis by Cox's proportional hazards model was used to evaluate the factor(s) that affected the recovery of erectile function and sexual intercourse. RESULTS: The recovery rates of erectile function were 49% at 3 years and 79% at 5 years. For recovery of sexual intercourse the rates were 36% at 3 years and 57% at 5 years. Multivariate analysis revealed that the preoperative NPT value was the only independent factor which significantly affected the recovery of erectile function. The age at surgery was a significant factor for recovery of sexual intercourse. CONCLUSION: Nerve-sparing operations can often, but not always, provide preservation or recovery of erectile function for patients who receive radical prostatectomy or cystoprostatectomy. Recovery of erectile function depends upon the preoperative NPT value and recovery of sexual intercourse depends upon the age of the patient.

The correlation between penile tumescence measured by the erectometer and penile rigidity by the RigiScan.

BACKGROUND: The goal of this study was to evaluate the correlation between increments of penile tumescence and penile rigidity measured by the erectometer and the RigiScan, respectively. METHODS: Nocturnal penile tumescence (NPT) was measured in 25 volunteers (mean age, 49.5 years). The erectometer and the RigiScan were used simultaneously for a total of 47 nights. We studied the correlation between maximum penile circumferential changes determined by the erectometer and penile rigidity patterns measured by the RigiScan. RESULTS: Maximum circumferential changes during NPT measured by the erectometer were well correlated to those determined by the RigiScan (correlation coefficient, 0.719). In addition, penile circumferential changes measured by the erectometer corresponded well to the penile rigidity pattern determined by the RigiScan (P=0.0001). Specifically, maximum penile circumferential changes of more than 30 mm and less than 10 mm had 70% positive predictive value and 100% negative predictive value for predicting the normal rigidity pattern, respectively. CONCLUSIONS: Penile circumferential changes measured by the erectometer were well correlated to penile rigidity measured by the RigiScan, particularly when the increments were larger than 30 mm or less than 10 mm. These results suggested that the erectometer was a useful tool to estimate the penile rigidity patterns of the RigiScan.

Extraperitoneal bladder rupture secondary to rectal impalement.

Impalement injury to both the urinary bladder and the rectum is a rare occurrence. A 45-year-old man was referred to our hospital because he had been stabbed through the internal femoral skin by a steel bar. Retrograde cystography and computed tomography failed to demonstrate bladder rupture. We carried out cystoscopy (CS) because of the existence of gross hematuria and found a penetrating wound in the posterior wall. Colon fiberscopy revealed two wounds in the rectum, one of which communicated with the bladder. A diagnostic laparoscopy revealed no associated injuries in the peritoneal cavity. Vesicorectal injury was diagnosed and treatment included transanal closure of fistulas and indwelling ureteral and urethral catheters. Postoperative CS revealed complete closure of the injury.

Treatment of erectile dysfunction: what should we do next?

Because sildenafil (Viagra) is scheduled to be clinically available in the near future, urologists in Japan must prepare for changes in the treatment of erectile dysfunction. The drug will surely influence our current clinical style of diagnosis and treatment of the dysfunction. We herein discuss this issue, referring to favorable and unfavorable effects that will be brought about by the drug. We also propose several future studies that we should do, including those on testosterone replacement therapy. We present results of our experiment using testosterone replacement therapy in aged rats and speculate about the mechanism by which the hormone replacement works in the sex center of the brain.

Regional specificity of localized cortical lesions in West syndrome.

West syndrome, although classified as a generalized epilepsy, is associated with localized cerebral lesions in some cases. However, similar localized cortical abnormalities usually can result in partial epilepsy, instead of West syndrome. We performed this study to determine the additional factors that result in West syndrome instead of partial epilepsy in patients with localized cerebral lesions. We reviewed the pathologic features, topographic localization, and side of unilaterally defined cerebral lesions in relation to the seizure types in 39 epileptic patients, including five patients who presented with West syndrome. The lesions of all five patients with West syndrome involved the temporal or occipital lobes (or both). Among the nine with an occipital lesion, four had West syndrome. In the 19 with a temporal lesion, three had West syndrome. However, in the 16 patients with a frontal lesion, none exhibited epileptic spasms. In four of the five with West syndrome the lesions were on the right side; 23 had lesions on the right, 16 had them on the left. Temporo-occipital lesions and lesions on the right were related to the genesis of West syndrome, which would be in close correlation with normal brain maturation.

[Epileptogenesis of acute encephalitis and acute encephalopathy: epilepsy with its onset in the acute phase and without a latent period].

Epileptogenesis was evaluated in 60 patients with acute encephalitis and in 10 patients with acute encephalopathy. Forty-seven patients have been seizure-free during for more than three years' follow-up (Group III). On the other hand, 23 patients developed epilepsy. Among them, 18 patients developed epilepsy after a latent period of 1 month to 2 3/12 years (Group I). In Group I, a younger age of the onset, a long period of disturbed consciousness and a high activity of CSF neuron-specific enolase (NSE) was associated with refractory epilepsy. The other five patients had continuous seizures from the acute phase of encephalitis without a latent period (Group II). They had more than 2 types of partial motor seizures which occurred frequently during the acute phase of encephalitis. The NSE activity in the CSF of patients in Group II was less than 50 ng/ml, being similar to those in Group III. The epilepsy in Group II, however, was the most refractory. The reason for the development of this continuous refractory epilepsy remained obscure.

[Validity analysis of Sapporo Medical University-sexual function questionnaire].

BACKGROUND: We evaluated the validity of the Sapporo Medical University-sexual function questionnaire, comparing the response to each question of patients having sexual dysfunction with those of normal volunteers as controls. PATIENTS AND METHODS: Responses from 335 patients with sexual dysfunction and 490 normal volunteers aged from 20 to 39 years old were evaluated. We compared mean scores of each question for patients having sexual dysfunction with those for controls. Discriminant analysis was used for evaluating which questions contributed more strongly to discriminating patients having the disease from controls. The analysis was also used for validating the questionnaire. RESULTS: Mean scores for patients with sexual dysfunction were significantly lower than those for controls in all questions. Nine of the 11 questions were statistically useful to discriminate these two groups with discriminant analysis. The analysis also revealed that questions about frequency of erection, rigidity of the erectile penis and duration of erection highly contributed to discriminate these two groups. The discriminant analysis achieved high sensitivity and specificity for classifying the groups. CONCLUSION: These results suggest that the use of the Sapporo Medical University-sexual function questionnaire is valid for discriminating patients with sexual dysfunction from subjects with normal sexual function.

The effects of alterations in nitric oxide levels in the paraventricular nucleus on copulatory behavior and reflexive erections in male rats.

PURPOSE: To examine the effects of altered nitric oxide (NO) levels in the paraventricular nucleus (PVN) on copulatory behavior and reflexive erections in male rats. MATERIALS AND METHODS: Extracellular nitrite (NO2-) and nitrate (NO3-) levels were measured in the PVN following administration of the NO precursor L-arginine (L-arg, 10 mM), the NO synthase inhibitor N(G)-monomethyl L-arginine (L-NMMA, 10 mM), or Ringer's solution via a dialysis probe to the PVN. The effects of alterations in extracellular NO on reflexive erections and copulatory behavior were assessed. RESULTS: L-arg administration was associated with significant elevations of extracellular NO2- and NO3- in the PVN, while L-NMMA significantly reduced NO2- and NO3- levels. A corresponding increase in reflexive erections was noted during infusion of L-arg in the PVN, with a corresponding decrease in reflexive erections observed during administration of L-NMMA into the PVN (Student's t test for paired samples, p <0.05). Mount rate was unaffected by infusion of the either L-arg or L-NMMA. CONCLUSIONS: Altered NO levels in the PVN affected the frequency of reflexive erections, but not the mount rate. These studies contrast with previous observations of the effects of altered NO levels in the MPOA, and support the hypothesis that physiological specificity in the actions of NO on discrete brain nuclei may have important implications to erectile physiology and dysfunction.

Effects of levodopa on nocturnal penile tumescence: a preliminary study.

We studied the effects of levodopa (L-dopa), which is reported to increase the dopamine level in the brain, on male erectile function. Of the 21 subjects studied, 12 subjects who were 50 years old or older showed significant increases of two nocturnal penile tumescence (NPT) parameters, NPT frequency and total tumescence time, with L-dopa. On the other hand, in nine subjects who were younger than 50 years, maximum penile circumference increase showed a significant increment with L-dopa. This significant increment of NPT with L-dopa was not observed in the subjects who had low androgen levels. The results of this preliminary study show a positive relationship between administration of L-dopa and erectile function. L-Dopa administration may improve erectile function in subjects aged 50 years and older who have normal androgen levels.

Restoration of sexual behavior and dopaminergic neurotransmission by long term exogenous testosterone replacement in aged male rats.

PURPOSE: We investigated the effects of long-term testosterone replacement on copulatory behavior and dopaminergic neurotransmission in the medial preoptic area of aged male rats. MATERIALS AND METHODS: The rats were divided into 3 groups depending on testosterone replacement. Those in the long-term replacement group were castrated at the age of 12 months and received testosterone replacement thereafter for 12 months. In the short-term replacement group, rats were castrated at the age of 22 months and high or low dose testosterone replacement was done for 2 months. The control group consisted of aged rats 24 months old and young rats 12 weeks old, neither of which had been castrated or received testosterone replacement. We observed sexual behavior in rats of these groups. After a behavioral test, we measured the tissue concentration of dopamine in the MPOA and the change rate of the extracellular dopamine level induced by infusion of N-methyl-D-aspartic acid (NMDA) in the MPOA and compared the long-term replacement and no-replacement groups. RESULTS: The rats in the long-term replacement group showed a mount rate at the same level as that of young rats at 6 weeks after starting replacement and it was maintained to 24 months of age. Their mount rate was significantly higher than that of the rats with the short-term replacement. A significantly higher change rate of dopamine release was recognized in the long-term group; however, no significant difference in the concentration of dopamine was recognized between aged rats with long-term replacement and those without replacement. CONCLUSIONS: Aged rats (24 months old) with long-term testosterone replacement maintained almost the same level of mount behavior as young rats (12 weeks old). The results imply that long-term testosterone replacement may favorably alter the decline in the process of sexual activity with aging. The restoration by testosterone replacement of dopaminergic activity in the MPOA may be involved in the maintenance of sexual function in aged rats.

Evaluation of the alleviative action of neurotropin for penile pain associated with intracavernous injection of prostaglandin E1 assessed using the visual analogue scale.

We examined whether penile pain associated with intracavernous injection of PGE1 could be alleviated with a intracavernous injection of neurotropin, a non-protein, bioactive agent extracted from skin tissue with inflammation elicited by the Vaccinia virus. Twenty-three patients with erectile dysfunction were enrolled in this study. They were divided into two groups. The first group was allocated 20 micrograms of PGE1 alone first, followed by PGE1 plus 1.5 ml of neurotropin after two weeks. The second group was allocated PGE1 plus 1.5 ml of neurotropin first, followed by PGE1 alone after two weeks. Pain was evaluated by the visual analogue scale (VAS). In the 17 patients reporting discomfort, pain scores for PGE1 injection with neurotropin were significantly lower than those without neurotropin. No patients showed local or systemic complications that might be related to neurotropin. From these data we conclude that neurotropin may be an effective and safe drug for penile pain associated with PGE1 intracavernous injection.

[A case of neuroblastoma with abnormal LD isoenzyme].

We encountered a patient with neuroblastoma showing remarkably high total LD activity (12,585 IU/l). His liver and heart function was normal. In the serum LD isoenzyme pattern, LD1 was increased, and LD2 extra band (LD2 ex) was observed on the negative pole side of LD2. However, LD2 ex was absent in erythrocytes of the patient, which demonstrates the exclusion of genetic factors. Neither the enzyme counter current method or immunofixation showed immune complexes, excluding anomalies. The LD isoenzyme in a metastatic lymphnode lesion before treatment showed increased LD1. The LD isoenzymes in the tissue, removed after 5 courses of chemotherapy, showed predominance of LD3 and absence of LD2 ex. Rapid decreases in the serum total LD activity and LD1 fraction and the disappearance of LD2 ex after chemotherapy suggest that these changes in the two LD fractions are associated with production of abnormal LD (LD2 ex) by the tumor.

Effect of the nitric oxide level in the medial preoptic area on male copulatory behavior in rats.

We investigated the influence of the extracellular nitric oxide (NO) level on male copulatory behavior. We confirmed the changes of nitrite (NO2-) and nitrate (NO3-) in the medial preoptic area (MPOA) by administration of the NO precursor L-arginine (L-Arg, 10 mM) or the NO synthase inhibitor NG-monomethyl-L-arginine (L-NMMA, 10 mM) via a dialysis probe. NO2- and NO3- were measured simultaneously by an in vivo microdialysis method coupled with the Griess reaction. L-Arg induced significant elevations of extracellular NO2- and NO3-. L-NMMA significantly reduced NO2- and NO3- levels. We observed male copulatory behavior during infusion of L-Arg or L-NMMA. The mount rate of male rats significantly increased during infusion of L-Arg in the MPOA. Administration of L-NMMA reduced the mount rate. These findings suggested that the elevation of extracellular NO in the MPOA facilitates male copulatory behavior of rats, whereas the decrease of NO reduces their copulatory behavior.