Pinacidil抑制线粒体和死亡受体通路减少大鼠脑缺血再灌注后神经元凋亡(英文)

目的探讨ATP敏感性钾通道开放剂pinacidil对大鼠脑缺血再灌注后神经元凋亡的保护作用及信号转导机制。方法 100 只Wistar 雄性大鼠随机分为四组:A 组(假手术组)、B组 (缺血组)、C 组 (KATP开放剂处理组)及D组 (KATP开放剂和阻断剂处理组)。用线栓法制备大鼠大脑中动脉缺血(middle cerebral artery occlusion,MCAO)模型,用DNA断端末端标记法(terminal-deoxynucleotidytransferase-mediated dUTP-biotin nick end labeling,TUNEL)检测神经元凋亡,用原位杂交方法检测caspase-3、caspase-8及caspase-9 mRNA的表达。结果 (1) C组12 h、24 h、48 h、72 h 时间点的凋亡细胞数较 B、D 组显著减少(P<0.05 或 P<0.01) ;B 组和 D组之间无显著性差异(P>0.05)。(2) C 组 caspase-3 mRNA 和 caspase-8 mRNA 在各时间点及 caspase-9 mRNA 在 12 h、24 h、48 h、72h 时间点的表达显著少于B组和D组(P<0.01或P<0.05),B组和D组之间无显著性差异(P>0.05)。结论 KATP通道开放剂能显著减少大鼠脑缺血再灌注后的细胞凋亡及caspase-3、caspase-8及caspase-9 mRNA的表达。KATP通道开放剂可能通过抑制线粒体通路和死亡受体通路降低神经元凋亡,保护缺血再灌注损伤后的脑组织。     

Remote-controlled catheter ablation of accessory pathways: results from the magnetic laboratory.

AIMS: This study evaluates feasibility, safety, and efficacy of magnetic remote-controlled accessory pathway (AP) ablation. METHODS AND RESULTS: The novel magnetic navigation system (MNS) (Niobe, Stereotaxis) creates a steerable magnetic field (0.08 T) controlling the distal magnetic tip of an ablation catheter. In conjunction with a catheter advancer system (Cardiodrive, Stereotaxis) remote catheter ablation is enabled. Conventional electrophysiology study identified AP conduction in 59 patients (37 males, 36+/-14 years, 60 APs). First generation 1-magnet tip (1-M) (group I, n=18), second generation bipolar 3-magnet tip (3-M) (group II, n=27), and third generation quadripolar 3-magnet tip catheters (3-M quad.) (group III, n=14) were used for magnetic remote-controlled ablation. Successful AP ablation was achieved in 67% (group I), 85% (group II), and 92% (group III). A significant decrease of median [IQR: Q1-Q3] fluoroscopy time and dosage was observed: 21.2 [12.1-33.8] min, 1110 [395-3234] microGym2 (group I); 6.5 [4.4-15.4] min, 290 [129-489] microGym2 (group II), and 4.9 [3.4-8.0] min, 129 [74-270] microGym2 (group III). Mean procedure time (217+/-67 min; 182+/-68 min, and 172+/-90 min) significantly decreased in group III. Median number [Q1-Q3] of radiofrequency current applications in groups I, II, and III was 4 [2-9], 4 [2-6], and 2 [2-4], respectively. No complications occurred. CONCLUSION: Remote AP ablation is safe and feasible using the novel MNS. Introduction of the 3-magnet quadripolar ablation catheter significantly improved the efficacy of the procedure.     

Hepatic UDP-glucose 13C isotopomers from [U-13C]glucose: a simple analysis by 13C NMR of urinary menthol glucuronide.

Menthol glucuronide was isolated from the urine of a healthy 70-kg female subject following ingestion of 400 mg of peppermint oil and 6 g of 99% [U-(13)C]glucose. Glucuronide (13)C-excess enrichment levels were 4-6% and thus provided high signal-to-noise ratios (SNRs) for confident assignment of (13)C-(13)C spin-coupled multiplet components within each (13)C resonance by (13)C NMR. The [U-(13)C]glucuronide isotopomer derived via direct pathway conversion of [U-(13)C]glucose to [U-(13)C]UDP-glucose was resolved from [1,2,3-(13)C(3)]- and [1,2-(13)C(2)]glucuronide isotopomers derived via Cori cycle or indirect pathway metabolism of [U-(13)C]glucose. In a second study, a group of four overnight-fasted patients (63 +/- 10 kg) with severe heart failure were given peppermint oil and infused with [U-(13)C]glucose for 4 hr (14 mg/kg prime, 0.12 mg/kg/min constant infusion) resulting in a steady-state plasma [U-(13)C]glucose enrichment of 4.6% +/- 0.6%. Menthol glucuronide was harvested and glucuronide (13)C-isotopomers were analyzed by (13)C NMR. [U-(13)C]glucuronide enrichment was 0.6% +/- 0.1%, and the sum of [1,2,3-(13)C(3)] and [1,2-(13)C(2)]glucuronide enrichments was 0.9% +/- 0.2%. From these data, flux of plasma glucose to hepatic UDPG was estimated to be 15% +/- 4% that of endogenous glucose production (EGP), and the Cori cycle accounted for at least 32% +/- 10% of GP.     

The 12‐Lead ECG in Patients with Mahaim Fibers

The aim of this review article is to discuss the electrocardiographic presentation of the so called variants of pre‐excitation (“Mahaim fibers”) during sinus rhythm and tachycardia.     

旁道位置与室上性心动过速首次发作时年龄及性别的关系探讨

目的为了解旁道位置与室上性心动过速初次发作时年龄及性别的关系.方法对128例已进行过射频消融的患者进行了回顾性分析.结果男性左侧旁道发病时平均年龄大于右侧及中隔旁道平均为14岁和9岁;大于女性左侧旁道7岁,男性显性旁道发病时平均年龄小于隐匿性旁道7岁.而女性显性旁道与隐匿性旁道、左侧旁道与右侧旁道发病时平均年龄无显著性差异.结论旁道位置与室上速初次发作时年龄及性别有关.     

Head-impulse testing in Fabry disease - vestibular function in male and female patients

Aim : To study the prevalence of peripheral vestibular deficit in male and female patients with Fabry disease and to assess the effect of enzyme replacement therapy (ERT) on peripheral vestibular function using quantitative head-impulse testing. Methods : Using dual search-coils the vestibulo-ocular reflex during rapid rotational head thrusts to both sides was recorded in 21 patients (13 male, 8 female) with Fabry disease prior to ERT initiation. ERT consisted of infusions of gene-activated human α-galactosidase A (agalsidase alfa; Replagal™) every 2 weeks at doses of 0.2mg/kg. Eight patients were tested again approximately 6 and 12 months after the initiation of ERT. Results : At baseline examination, 15 of the patients with Fabry disease (71%; 11 males, 4 females) showed reduced peripheral vestibular function. The deficit was unilateral in nine patients (3 females) and bilateral in six patients (1 female). The severity of the vestibular deficit was not significantly different between male and female patients. After 12 months of ERT, the average vestibular deficit on the weaker side tended to improve; however, the change was not significant ( p = 0.10).
Conclusion : Fabry disease affects peripheral vestibular function in both male and female patients. Females seem to be affected less frequently than males, but, on average, vestibular deficits are not different between the two groups. To confirm or reject the tendency for vestibular improvement during ERT, more patients need to be tested and longer follow-up periods are required.     

Radiofrequency Catheter Ablation of the Anterosuperior and Posteroinferior Atrial Approaches to the AV Node for Treatment of AV Nodal Reentrant Tachycardia

Catheter Ablation Techniques in AVNRT. Radiofrequency catheter ablation has been established as a first-line curative treatment modality in patients with symptomatic AV nodal reentrant tachycardia (AVNRT). The successful sites of stepwise catheter ablation approaches of the so-called fast and slow pathways strongly suggest that AVNRT involves the atrial approaches to the AV node. The typical fast pathway ablation sites are located anterosuperior toward the apex of the triangle of Koch, which also contains the compact AV node, whereas the usual slow pathway ablation sites are located posteroinferior toward the base of the triangle of Koch at a greater distance to the compact AV node and bundle of His. Accordingly, ablation studies with large patient cohorts have demonstrated that fast pathway ablation carries a higher risk of inadvertent complete AV block. Thus, the slow pathway is clearly the primary target site, and fast pathway ablation is rarely necessary. Different approaches for slow pathway ablation have been elaborated: anatomically oriented stepwise techniques, ablation guided by double potentials recorded within the area of the slow pathway insertion, and combined techniques. The modern concept of AVNRT suggests that this arrhythmia involves the highly complex three-dimensional nonuniform anisotropic AV junctional area. Accordingly, mapping and ablation studies demonstrated that the anterior approach is not identical with fast pathway ablation, and the posterior approach is not identical with slow pathway ablation. Therefore, it is essential for interventional electrophysiologists to familiarize themsdves with the anatomic and electrophysiologic details of this complex and variable specialized AV junctional region. In this review, the anatomic and pathophysiologic aspects of the AV junctional area as they relate to interventional therapy are summarized briefly, and the catheter techniques for ablation of the so-called fast and slow AV nodal pathways for the treatment of AVNRT are described.     

血清补体系统在流行性出血热患者中的变化及其意义

应用单向免疫扩散法测定了流行性出血热(EHF)患者的7种补体成份和血浆素原(Pg).结果表明,CT脂酶抑制剂在少尿期、多尿期和恢复期均高于正常(P<0.01);补体C_1q在多尿期高于正常(P<0.01);补体C_4在发热期和少尿期低于正常(P<0.01),以后逐渐恢复正常;补体C_3,C_5和C_9的变化与C_4相似;B因子在少尿期低于正常(P<0.01),在多尿期高于正常(P<0.05);Pg始终高于正常水平但在少尿期有回降.说明EHF患者不仅有补体经典途径的识别阶段、活化阶段和膜攻击阶段的变化,而且亦有旁路激活,其活化程度与病情有关.     

Auditory and vestibular system findings in patients with vertebrobasilar dolichoectasia

Impairment of the auditory-vestibular system has been reported in patients with vertebrobasilar dolichoectasia (VBD), but little is known about the underlying cause of the symptoms. Auditory testing (pure tone audiometry, auditory brain stem response and stapedius reflex) and vestibular tests (assessment of nystagmus, eye tracking tests, caloric test and rotational test) were performed in 23 patients with auditory-vestibular symptoms and/or cranial nerve impairment associated with VBD. Specific evidence of auditory and/or vestibular system impairment was observed in 19 cases (83%). Among patients with abnormal test findings, 47% had evidence suggesting peripheral impairment, 16% evidence suggesting central dysfunction, and 37% evidence suggesting both peripheral and central dysfunction. Although compression of the vestibulocochlear nerve plays an important role in the genesis of the auditory-vestibular dysfunction in patients with VBD, mechanism such as brain stem-cerebellar ischemia and impaired blood supply to the vestibular labyrinth may be just as important.     

Primary orthostatic tremor is an exaggeration of a physiological response to instability.

Primary orthostatic tremor (POT) is a rare disorder characterised by an intense sense of unsteadiness upon standing and a 16-Hz tremor in which the timing between tremor bursts in different muscles (unilateral and bilateral) remains constant. Hitherto, similar EMG activity has not been described in healthy subjects and it has been postulated that the oscillations seen in POT are primarily pathological. In this study, EMG was recorded from tibialis anterior in healthy subjects who were made unsteady through vestibular galvanic stimulation or leaning backwards. Under these conditions, a peak at approximately 16 Hz was seen in the coherence between the left and right tibialis anterior. This bilateral coherence was absent when the subjects activated the same muscles when not unsteady. These data indicate the existence of a physiological system involved in organising postural responses under circumstances of imbalance and characterised by a highly synchronised output at approximately 16 Hz. In addition, the results suggest that the core abnormality in POT may be an exaggerated sense of unsteadiness when standing still, which then elicits activity from a 16-Hz oscillator normally engaged in postural responses.