Tissue distribution and hypotensive effect of prazosin in the conscious rat

We investigated the hypotensive effect and tissue distribution of prazosin (1 mg/kg i.v.) in conscious rats. This dose caused an immediate fall in blood pressure, associated with a nonsignificant increase in heart rate. Blood pressure then gradually rose to control over a 2-h period. Prazosin was measured in plasma and tissue samples by high-pressure liquid chromatography. Highest concentrations of drug were found in liver and kidney and the lowest in brain. The rate of decline of prazosin from plasma was similar to its decline from the tissues, indicating a rapid equilibrium. This rate of disappearance was also similar to the decay of the hypotensive response and suggests that prazosin in plasma may be in equilibrium with prazosin at its site of action.     

Continuous facial nerve monitoring during pleomorphic adenoma recurrence surgery

OBJECTIVES: Surgery of recurrent pleomorphic adenoma (RPA) is known to lead to a high facial nerve complication rate. The efficacy of the continuous facial nerve monitoring (CFNM) technique remains to be proven in RPA surgery. The goal was thus to evaluate facial nerve palsy rates and the recovery period after parotidectomy for RPA using CFNM by way of continuous electromyography and to compare these rates and the operation time with those of patients who had undergone surgery without facial nerve monitoring. DESIGN: Cohort study. PATIENTS: Forty-seven patients were referred for RPA (1981-2003). Among them, 32 (18 unmonitored and 14 monitored) patients displayed no preoperative facial palsy, and histologic analyses revealed evidence of recurrence. The operation time and the extent and duration of postoperative facial nerve palsy were examined in both groups (monitored vs. unmonitored). Both groups had a similar clinical appearance distribution. RESULTS: Facial nerve paralysis was estimated using the House-Brackmann grading scale. CFNM reduced the intensity of facial nerve paralysis independently of the kind of surgery performed. The complete deficit rates were 0% for the monitored group and 5.6% for the unmonitored group. Postoperative facial nerve paralysis was significantly lower (P = .01) in the monitored group than in the unmonitored group. CFNM improved the duration of facial paralysis (P = .001) in the monitored group. The operation time was significantly lower in the monitored group than in the unmonitored group (P = .001). CONCLUSIONS: Routine use of CFNM during RPA surgery improves the surgical outcome. The facial nerve deficit can be reduced, and the recovery of facial nerve function is faster.     

A case of an anomalous radial artery arising from the thoracoacromial trunk

We present a case of an anomalous radial artery (ARA), which arose as a branch of the thoracoacromial trunk. After giving rise to the lateral thoracic artery, the ARA continued superficially through the brachium and antebrachium, terminating as the deep palmar arterial arch. This anomalous artery was found to completely replace the radial artery which normally arises from the brachial artery. Embryological considerations and possible clinical consequences are discussed.     

Activation of XII motoneurons and premotor neurons during various oropharyngeal behaviors

Neural control of tongue muscles plays a crucial role in a broad range of oropharyngeal behaviors. Tongue movements must be rapidly and accurately adjusted in response to the demands of multiple complex motor tasks including licking/mastication, swallowing, vocalization, breathing and protective reflexes such as coughing. Yet, central mechanisms responsible for motor and premotor control of hypoglossal (XII) activity during these behaviors are still largely unknown. The aim of this article is to review the functional organization of the XII motor nucleus with particular emphasis on breathing, coughing and swallowing. Anatomical localization of XII premotor neurons is also considered. We discuss results concerned with multifunctional activity of medullary and pontine populations of XII premotor neurons, representing a single network that can be reconfigured to produce different oromotor response patterns. In this context, we introduce new data on swallowing-related activity of XII (and trigeminal) motoneurons, and finally suggest a prominent role for the pontine K?lliker-Fuse nucleus in the control of inspiratory-related activity of XII motoneurons supplying tongue protrusor and retrusor muscles.     

Cough determinants in patients with neuromuscular disease

Neuromuscular disease leads to cough impairment. Cough augmentation can be achieved by mechanical insufflation (MI) or manually assisted coughing (MAC). Many studies have compared these two methods, but few have evaluated them in combination. In 155 neuromuscular patients, we assessed determinants of peak cough flow (PCF) using stepwise correlation. Maximal inspiratory capacity contributed 44% of the variance (p<0.001), expiratory reserve volume 13%, and maximal expiratory pressure 2%. Thus, augmenting inspiration seems crucial. However, parameters dependent on expiratory muscles independently influence PCF. We measured vital capacity and PCF in 10 neuromuscular patients during cough augmentation by MI, MAC, or both. MI or MAC significantly improved VC and PCF (p<0.01) as compared to the basal condition and VC and PCF were higher during MI plus MAC than during MAC or MI alone (p<0.01). In conclusion, combining MAC and MI is useful for improving cough in neuromuscular patients.     

Patient characteristics and setting variables related to use of restraint on four inpatient psychiatric units for youths

OBJECTIVES: This study examined the characteristics of children and adolescents who were restrained during brief inpatient psychiatric treatment and identified whether restraint use was related to the characteristics of the youths or to the setting-time of day, day of the week, place, or programming. Incidents related to restraint use were also examined. METHODS: Charts were reviewed for 100 youths who were admitted to four inpatient units between December 1998 and January 2000. RESULTS: Thirty-one youths were not restrained, 57 were restrained once or twice, and 12 were restrained three or more times. Youths were significantly more likely to be restrained if they were male, had multiple admissions to the facility during the study period, remained in the hospital longer, had been given a diagnosis of a psychotic disorder, or had a previous psychiatric hospitalization. Youths who were restrained were also more likely to be enrolled in special education or to be in foster care or in custody of the Department of Children and Family Services. Also, these youths were more likely to have a history of voicing suicidal ideation and attempting suicide. No single setting variable was significantly related to restraint use. Incidents that prompted restraint generally involved agitation, threats, or assaults. CONCLUSIONS: Youths who were at greatest risk of being restrained during brief inpatient treatment shared particular characteristics related to greater use of inpatient services, guardianship arrangements, special education placement, and history of suicide attempts. Inpatient staff members should remain particularly alert to the processing and regulation problems of these groups of patients.     

Prevalence of essential tremor in Singapore: a study on three races in an Asian country

To investigate the prevalence of Essential Tremor (ET) in Singapore and compare the rates between Singaporean Chinese, Malays, and Indians, a community-based survey among a disproportionate random sample of 15,000 individuals (9000 Chinese, 3000 Malays, 3000 Indians) aged 50 years and above was conducted. In phase 1, trained interviewers conducted a door-to-door survey using a screening questionnaire for Parkinson's disease. In phase 2, medical specialists examined participants who screened positive to evaluate for the presence of postural or kinetic tremor of the upper limbs, or head tremor. Participants with suspected ET had their diagnosis confirmed in phase 3 by a movement disorders specialist and fellow based on the latest core diagnostic criteria. Forty participants with classic ET were identified. The prevalence rate (PR) of ET was 2.37 per 1000 (95% CI: 1.65-3.32), age-adjusted to UICC world standard population. The PR was significantly higher in males (p=0.01) and increased significantly with age (p<0.001). Indians (PR=4.94 per 1000, 95% CI: 2.63-9.04) were 1.8 times more likely to have ET than Chinese (PR=2.77 per 1000, 95% CI: 1.78-4.17) (p=0.08). No Malays with ET were identified. The data suggest that the prevalence of ET increases with age, is higher in males and may be higher amongst Indians.     

Levetiracetam for the treatment of generalized dystonia

We report the case of a woman with generalized dystonia whose symptoms improved with the use of levetiracetam. Improvements were noted in blepharospasm, cervical, and truncal dystonia. The patient has been on LEV for a total of 20 weeks, and has experienced sustained improvement of symptoms.     

Novel features of nitric oxide,endothelial nitric oxide synthase,and atherosclerosis

There is a complex pathophysiologic scenario involving nitric oxide (NO), endothelial nitric oxide synthase (_eNOS), and the development of atherosclerosis and unstable atheroma. Endothelial damage induced by atherosclerosis leads to the reduction in bioactivity of _eNOS with subsequent impaired release of NO. An important mechanism is local enhanced degradation of NO by increased generation of reactive oxygen species and other free radicals, with subsequent cascade of oxidationsensitive mechanisms in the arterial wall. Novel molecular approaches have resulted in the development of new strains of mice lacking _eNOS. These experimental models will help to understand how to implement NO-based therapies against atherosclerosis. L-arginine, the precursor of NO, has demonstrated beneficial effects in atherosclerosis and disturbed shear stress. The target or goal for new drugs should be the complete restoration of NOmediated signaling pathways in atherosclerotic arteries.