A double-blind, placebo-controlled study of the effect of imipramine on TRH-induced urinary urgency in healthy men.

We studied the effect of imipramine (IMI) on thyroid releasing hormone (TRH)-induced urinary urgency as a way of investigating the mechanism of the beneficial effect of IMI on enuresis. In a double-blind study, 12 normal, healthy men between 21 and 39 yr of age ranked their urge to urinate at 30-sec intervals following IV injection of TRH (500 micrograms) or saline. The subjects then were randomly assigned to either IMI (1 mg/kg) or placebo groups for 10 days, and the procedure was repeated. Compared to saline, TRH produced a significant elevation in urinary urgency in all subjects. IMI did not significantly blunt TRH-induced urinary urgency. Thus, the mechanism by which IMI affects enuresis is likely not mediated at the level of the urinary urgency induced by TRH.     

Development of hypothalamic opioid neurons: a combined immunocytochemical and [3H]thymidine autoradiographic study

Using a combined technique of immunocytochemistry and [3H]thymidine autoradiography, we have determined the "birth-date" of opioid peptide containing neurons in three hypothalamic nuclei. These include proopiomelanocortin neurons (indicated by ACTH immunoreactivity) in the arcuate nucleus, dynorphin A neurons in the supraoptic nucleus, and [Leu]enkephalin neurons in the periventricular nucleus. Arcuate proopiomelanocortin neurons were born very early in embryonic development, with peak heavy [3H]thymidine nuclear labelling occurring on embryonic day E12. Supraoptic dynorphin A neurons were also labelled relatively early (peak at E13). By contrast, [Leu]enkephalin neurons in the periventricular nucleus exhibited peak heavy nuclear labelling on day E14. The results indicate a differential genesis of these three opioid peptide containing neuronal groups in three different hypothalamic nuclei.     

Approach to sleep disorders in the nursing home setting. REVIEW ARTICLE

Evidence suggests that sleep disorders and sleep fragmentation are very common in nursing home residents. A variety of factors contribute to these sleeping difficulties, including age-related changes in sleep; the high prevalence of dementia, depression, medical illness and medications that affect sleep; and sleep disorders such as respiratory disturbance of sleep. Other important factors include common lifestyle characteristics in nursing home residents (such as inactivity, large amounts of time spent in bed, lack of bright light exposure, and poor sleep hygiene) and the disruptive night-time nursing home environment. Recent interventional studies suggest that improvement in the nursing home environment may be an important aspect of the management of sleeping difficulties. Assessment and management of sleeping problems in nursing home residents should involve comprehensive assessment and treatment of the multiple factors that can interfere with sleep. Residents who fail these interventions can be considered for treatment with sleeping medications. Unfortunately, there is little data on the effectiveness of sleeping medications and the specific management of sleep disorders in this setting. Future research should focus on clarifying the contribution of various environmental factors to sleep impairment, and the testing of these various interventions on sleep.     

Two distinct types of depolarizing afterpotentials are differentially expressed in stellate and pyramidal‐like neurons of entorhinal‐cortex layer II

Two types of principal neurons, stellate cells and pyramidal‐like cells, are found in medial entorhinal‐cortex (mEC) layer II, and are believed to represent two distinct channels of information processing and transmission in the entorhinal cortex–hippocampus network. In this study, we found that depolarizing afterpotentials (DAPs) that follow single action potentials (APs) evoked from various levels of holding membrane voltage (V_h) show distinct properties in the two cells types. In both, an evident DAP followed the AP at near‐threshold V_h levels, and was accompanied by an enhancement of excitability and spike‐timing precision. This DAP was sensitive to voltage‐gated Na⁺‐channel block with TTx, but not to partial removal of extracellular Ca²⁺. Application of 5‐μM anandamide, which inhibited the resurgent and persistent Na⁺‐current components in a relatively selective way, significantly reduced the amplitude of this particular DAP while exerting poor effects on the foregoing AP. In the presence of background hyperpolarization, DAPs showed an opposite behavior in the two cell types, as in stellate cells they became even more prominent, whereas in pyramidal‐like cells their amplitude was markedly reduced. The DAP observed in stellate cells under this condition was strongly inhibited by partial extracellular‐Ca²⁺ removal, and was sensitive to the low‐voltage‐activated Ca²⁺‐channel blocker, NNC55‐0396. This Ca²⁺ dependence was not observed in the residual DAP evoked in pyramidal‐like cells from likewise negative V_h levels. These results demonstrate that two distinct mechanism of DAP generation operate in mEC layer‐II neurons, one Na⁺‐dependent and active at near‐threshold V_h levels in both stellate and‐pyramidal‐like cells, the other Ca²⁺‐dependent and only expressed by stellate cells in the presence of background membrane hyperpolarization. © 2015 Wiley Periodicals, Inc.     

全椎间盘置换术治疗腰椎间盘源性退行性疾病

目的 评价腰椎全椎间盘置换治疗腰椎间盘源性退行性疾病的效果.方法 应用两种人工腰椎间盘移植物治疗90例108节段具有明确腰椎间盘源性退行性疾病且6个月保守治疗无效的患者,男28例,女62例;年龄25~54岁,平均39.2岁;单节段植入85例,双节段10例,三节段1例;L3-4节段6例,L4-5节段39例,L5S1A节段63例.使用Prodisc L人工腰椎间盘48节段,Maverick人工腰椎间盘60节段.手术均取腹膜后人路.术后采用改良Odom评估、Oswestry评分、VAS评分及影像学检查四种方法对症状及疼痛改善程度进行评价.结果 手术时间75~160min,平均115.5min.术中血管损伤1例.术后并发深静脉血栓1例.术后90例患者均随访12个月.随访时间分别为:术后4、6、26、52周.术后Odom评估显示:优76例,良10例,可4例,优良率95.55%.住院时间2.5~6d.平均3.4d.术后翻修2例.影像学检查:假体下沉2例,两种假体移植物均无明显向前或后迁移.结论 应用腰椎全椎间盘置换可恢复退变节段的间盘高度和神经根管的高度及前、后径,保留腰椎后柱结构的完整性和稳定性.     

Surgical management of popliteal artery aneurysms: Which factors affect outcomes?

OBJECTIVE: Popliteal artery aneurysm (PAA) is uncommon. The clinical presentation of PAA includes rupture, embolism, and thrombosis. In this article, we evaluate the results of our 20-year experience with surgical management of PAAs, analyzing the role of anatomic, clinical, and surgical factors that potentially affect early and long-term results. METHODS: From January 1984 to December 2004, 159 PAAs in 137 patients were operated on at our department. Data from all the patients were retrospectively collected in a database. PAAs were asymptomatic in 67 cases (42%); 5 (3%) PAAs were ruptured. In 51 cases (32%), PAA caused intermittent claudication. The remaining 36 limbs (23%) had threatening ischemia due in 30 cases to acute PAA thrombosis, in 4 cases to chronic PAA thrombosis, and in 2 cases to distal embolization. In selected patients with acute ischemia, preoperative intra-arterial thrombolysis with urokinase was performed. Early results in terms of mortality, graft thrombosis, and limb salvage were assessed. Follow-up consisted of clinical and ultrasonographic examinations at 1, 6, and 12 months and yearly thereafter. Long-term survival, patency, and limb salvage rates were analyzed. RESULTS: Forty cases were treated with aneurysmectomy and prosthetic graft interposition; in 39 cases, the aneurysm was opened, and a graft was placed inside the aneurysm. Four patients had aneurysmectomy with end-to-end anastomosis. In 73 cases, ligation of the aneurysm with bypass grafting (39 with a prosthetic graft and 34 with an autologous vein) was performed. The remaining three patients underwent endovascular exclusion of their PAAs. A medial approach was used in 97 patients (61%), and a posterior approach was used in 59 patients (37.1%). The outflow vessel was in most cases (93.7%) the below-knee popliteal artery. Thirty-day amputation and death rates were 4.4% (7/159 limbs) and 2.1% (3/137 patients), respectively. The amputation rate was significantly higher in symptomatic limbs than in asymptomatic ones (6.5% and 1.4%, respectively; P = .05). Eight limbs (5%) had an early graft thrombosis that required a reintervention. Follow-up was available in 116 patients (84.7%) and 138 limbs (86%) with a mean follow-up time of 40 months (range, 1-205 months). The cumulative estimated 60-month survival, limb salvage, and primary and secondary patency rates were 84.2%, 86.7%, 66.3%, and 83.6%, respectively. Asymptomatic limbs had significantly better results than symptomatic ones in terms of limb salvage (93.4% and 80.4%, respectively; P = .03; log-rank, 4.2) and primary patency (86.5% and 51.6%, respectively; P = .001; log-rank, 10.3). Among symptomatic patients, results were better in claudicant limbs than in acutely ischemic ones in terms of limb salvage (90.5% and 58.7%, respectively; P = .001; log-rank, 17.5). Univariate analysis showed the absence of symptoms, the presence of two or three tibial vessels, the use of a posterior approach, the kind of intervention, and the site of distal anastomosis to significantly affect long-term patency. Cox regression for factors affecting 60-month primary patency showed that clinical presentation, runoff status, and the site of distal anastomosis significantly influenced long-term results. CONCLUSIONS: Results of surgery on asymptomatic PAAs are good-significantly better than those for symptomatic ones. Elective surgical intervention should be performed in patients with a low surgical risk and a long life expectancy when the correct indication exists. In thrombosed aneurysms, intra-arterial thrombolysis may represent an alternative to emergent surgical management. Our data demonstrated that results are similarly good in claudicants, and this fact confirms that only acute ischemia due to PAA thrombosis represents a real surgical challenge. In selected patients with focal lesions, a posterior approach seems to offer better long-term results. The runoff status and the site of distal anastomosis affect long-term patency as well.