STIMULUS FREQUENCY IN THE DETECTION OF NEUROMUSCULAR BLOCK IN HUMANS

Study of the literature on the physiology of neuromuscular transmissionsuggested two new methods of assessing the degree of neuromuscularblock in the human subject. These were, first, a comparisonof the height of the recorded twitch tensions developed in responseto repeated single stimuli applied at differing frequenciesand, second, examination of the extent of reduction in amplitudeof twitch tensions developed in response to a short train offour stimuli. In assessing the first method the use of threefrequencies of stimulation was tried (i.e., 0.1 Hz (c.p.s.),0.3 Hz and 1.0 Hz). It was found that as the frequency of stimulationwas increased there was reduction in the amplitude of the recordedtwitch response in curarized subjects, and that this reductionappeared to depend on the degree of curarization. In assessingthe second method a short train of four stimuli at 2 Hz wasused, and it was found that there was a progressive fade ofsuccessive recorded mechanical twitch responses in curarizedsubjects which again appeared to depend on the degree of curarization.It is suggested that the amplitude of the twitch response ata higher frequency expressed as a percentage of that at theslower rate, and the last response of the train of four expressedas a percentage of the first may be useful in measuring degreeof neuromuscular block in man.     

The Influence of Moisture Content on the Consolidation Properties of Hydroxypropylmethylcellulose K4M (HPMC 2208)

The effect of moisture content, compression speed and compression force on the compaction properties of HPMC K4M has been evaluated. As the moisture content increased from 0 to 14.9% w/w, the thickness of HPMC K4M compacts increased at constant compression force and speed. This increase in moisture content also resulted in a marked increase in the tensile strength of the tablets. At a speed of 15 mm s^?1 and force of 10 kN, as the moisture content increased from 0 to 14.9% w/w, the tensile strengths increased from 1.34 to 8.54 Mpa. Equivalent tensile strengths could be obtained with less compression force as the moisture content in the polymer was increased. Increasing the compression speed generally decreased the tensile strength of HPMC K4M tablets. The dependence of tablet porosity and tensile strength on compression speeds showed that HPMC K4M is consolidated by plastic deformation. At all compression speeds, an increase in moisture content reduced the percentage elastic recovery of HPMC compacts due to greater tablet consolidation. The lowest elastic recovery (1.18%) was found for tablets made at 15 mm s^?1 and 5 kN, containing 14.9% w/w moisture content.     

慢性心力衰竭患者血浆心脏间质成分的水平及其相关性

目的观察慢性心力衰竭(心衰)患者血浆金属蛋白酶(MMP)1,2及Ⅰ型、Ⅲ型前胶原氨基端肽,血管紧张素Ⅱ和醛固酮的水平.探讨这些成分与心衰发生以及相互之间的联系.方法对86例慢性心衰患者应用双抗体夹心法检测血清MMP1、MMP2水平.放射免疫法检测其PⅠ NP、PⅢNP、AngⅡ及ALD的水平.并与60例健康对照组进行对比研究.结果(1)慢性心衰患者血浆MMP1、PⅠNP、PⅢNP、AngⅡ和ALD水平均高于正常对照组(P＜0.01).(2)偏相关分析显示MMP1与MMP2、PⅠNP与PⅢNP、AngⅡ与ALD、PⅢNP与AngⅡ之间有正相关关系(P＜0.05).结论心脏间质成分MMP1、PⅠNP、PⅢNP及调节因子AngⅡ和ALD在心衰患者血浆中的水平升高,且不同间质成分之间存在着相互影响的关系.     

Assessment of Heart Rate Turbulence in the Acute Phase of Myocardial Infarction for Long-Term Prognosis

SADE, E., et al .: Assessment of Heart Rate Turbulence in the Acute Phase of Myocardial Infarction for Long-Term Prognosis. This study is designed to assess the value of heart rate turbulence (HRT) in the acute phase of MI for prediction of long-term mortality risk. The study included 128 consecutive acute MI patients with 24-hour Holter recordings to evaluate HRT (turbulence onset and slope), SDNN, mean RR interval, and ventricular premature beat frequency. LVEF was evaluated by two-dimensional echocardiography. Data from 117 patients (mean age 58 ± 11 years ) were available for further analysis. Twelve patients died during follow-up (mean 312 ± 78 days ). Although SDNN < 70 ms was the most powerful predictor of mortality among all presumed risk factors (hazard ratio 20 [95% CI 2.6–158]; P = 0.004) in univariate Cox regression analysis, in multivariate analysis LVEF ≤ 0.40 and turbulence slope ≤2.5 ms/RR interval were the only independent predictors of mortality (hazard ratio 6.9 [95% CI 1.8–26]; P = 0.006, hazard ratio 7.3 [95% CI 1.4–37]; P = 0.016, respectively). Addition of HRT parameters for LVEF increased remarkably the positive predictive value (60%) without any decrease in the negative predictive value (92%). Blunted HRT reaction within the first 24 hours of acute MI is an independent predictor of long-term mortality. Furthermore, its predictive power is comparable and also additive to that of LVEF. (PACE 2003; 26[Pt. I]:544–550)     

Exenatide improves excessive daytime sleepiness and wakefulness in obese patients with type 2 diabetes without obstructive sleep apnoea

We investigate the effects of exenatide on excessive daytime sleepiness (EDS), driving performance and depression score in patients with type 2 diabetes with EDS. Eight obese patients with diabetes but without obstructive sleep apnoea (OSA) participated in a placebo‐controlled single‐blind study during which multiple wakefulness and sleep latency test, Epworth score, driving performance, depression score, fasting glucose and glycated haemoglobin (HbA1c) levels were assessed at baseline, end of placebo and treatment phase at baseline and after 22 weeks of treatment. Mean (±standard error of the mean) age, body mass index (kg m²) and HbA1c [mmol mol^?1 (%)] of patients at baseline were 50 ± 4.9 years, 37.6 ± 1.1 and 65 ± 19 (8.06 ± 0.41), respectively. When compared to placebo, exenatide treatment was associated with a decrease in both subjective and objective sleepiness, based on the Epworth score reduction and the sleep latency increase assessed by multiple objective sleepiness and sustained attention (OSLER) tests, respectively. Mean sleep latency time (adjusted for change in HbA1c and weight) were 32.1 ± 1.7, 29.1 ± 1.7 and 37.7 ± 1.7, respectively (P = 0.002). Modelling for covariates suggested that improvement in mean sleep latency time is predicted by changes in weight (P = 0.003), but not by changes in HbA1c (P = 0.054). Epworth sleepiness score was reduced significantly (values for placebo versus exenatide: 11.3 ± 1.2 versus 5.7 ± 1.3; P = 0.003). No significant change was noted in the depression score and driving performance. Exenatide is associated with a significant reduction in objective sleepiness in obese patients with type 2 diabetes without OSA, independent of HbA1c levels. These findings could form a basis for further studies to investigate the pathophysiological mechanisms of sleepiness in obese patients with type 2 diabetes.     

Implantable Cardioverter Defibrillator Lead Endocarditis Causing Diffuse Right Atrial Abscess and Pulmonary Artery Embolism

Implantation of electrophysiological cardiac devices such as pacemakers and implantable cardioverter defibrillators has become a widely available and routine procedure in cardiovascular medicine. One of the most feared complications of device implementation is infection. Infection rates for these devices are reported to vary between 0.7% and 7.0%. Cardiac thromboembolic event is a recognized complication of permanent cardiac rhythm devices with an incidence of 0.6%–3.5%, unrelated to lead size or number. These complications are associated with high morbidity and mortality rates. In this case report, right atrial mass, right atrial abscess, perforation of tricuspid septal leaflet, and pulmonary embolism secondary to ICD lead endocarditis is presented. (PACE 2011; 34:e115–e117)     

黄骨髓对兔骨折愈合影响的实验研究

[目的]研究自体黄骨髓一期移植对骨折愈合作用的实验疗效,观察黄骨髓是否具有成骨能力,为进一步临床应用提供理论依据。[方法]36只新西兰大白兔随机分为3组,建立左侧胫骨骨折延迟愈合模型,A组仅以钢板内固定;B组钢板内固定后,植入空白明胶海绵,C组钢板内固定后,植入黄骨髓与明胶海绵复合物。术后每组分别于2、4、8、12周各处死3只动物,进行影像学检测、大体观察及HE染色检查,观察骨折愈合情况及骨痂形成情况。[结果]A组及B组在术后4周只可见少量骨痂形成,而C组在术后2周即可见骨痂形成,术后4周可见大量骨痂形成,至术后8周C组骨折线消失,而A、B组骨折线仍可见;术后12周,A、B组仍可见骨折线存在。[结论]黄骨髓在骨折后能明显促进骨折愈合,在预防骨不连或骨折延迟愈合中具有重要作用。     

The safety profile of anti-tumour necrosis factor therapy in inflammatory bowel disease in clinical practice: analysis of 620 patient-years follow-up

Background  Anti-TNF agents are now widely used in Crohn's disease (CD), and in ulcerative colitis (UC).
Aim  To review the safety profile of anti-TNF agents in all patients treated with infliximab in Edinburgh from 1999 to 2007.
Methods  Complete data were available on 202/207 patients comprising 157 CD, 42 UC and three coeliac disease. Median follow-up was 2.4 years (1.0–4.9) with a total of 620 patient-years follow-up. About 19.1% of CD patients were subsequently treated with adalimumab.
Results  Seven deaths (3.3%) occurred in follow-up; only one death was <1 year post-infliximab (at day 72, from lung cancer). A total of six malignancies (three haematological, three bronchogenic) and six cases of suspected demyelination (three with confirmed neurological disease) were reported. In the 90 days following infliximab, 95 adverse events (36 serious) occurred in 58/202 (28.7%) patients. In all, 42/202 (20.8%) had an infectious event (22 serious) and 27/202 (13.4%) of patients had an infusion reaction: 19 acute (four serious) and eight delayed (three serious).
Conclusions  Serious infections, malignancies and neurological disease complicate anti-TNF use in clinical practice. Although evidence for causality is unclear, potential mechanisms and predisposing factors need to be explored. In individual patients, the risk/benefit analysis needs to be carefully assessed and discussed prior to commencement of therapy.     

QRS Duration Widening: Reduced Synchronization of Endocardial Activation or Transseptal Conduction Time?

Antegrade activation of the His-Purkinje system (HPS) results in synchronized activation of the right ventricular (RV) and left ventricular (LV) endocardia forming normal, narrow QRS duration (QRSD). An alteration in septal activation and transseptal conduction time have been reported to be the causes for QRSD widening seen with bundle branch block. However, reduced synchronization of activation ofRVand LV endocardia as another potential mechanism for QRSD widening has not been systematically studied. Fifteen consecutive patients underwent radiofrequency ablation (RFA) for treatment of supraventricular tachycardia. After RFA, mean QRSD in normal sinus rhythm was 86 ± 8 ms with mean HV interval of 40 ± 5 ms. Right atrial (RA), coronary sinus (CS), simultaneous (S) RA-CS, RVapex (RVA), LV apex (LVA), and SRVA-LVA pacing were performed. Mean QRSD with RA, CS, SRA-CS pacing was similar to normal sinus rhythm (87 ± 7, 87 ± 8 and 88 ± 8 ms respectively). Mean QRSD was significantly longer with SRVA-LVA and either RVA or LVA pacing alone compared to normal sinus rhythm (106 t 8, 146 ± 12 and 157 ± 13 ms, respectively). However, QRSD was significantly shorter with SRVA-LVA pacing compared to either RVA or LVA pacing alone (P < 0.0001). We conclude that shorter QRSD with SRVA-LVA pacing compared to either RVA or LVA pacing alone is due to elimination of transseptal conduction delay; longer QRSD with SRVA-LVA pacing compared to sinus or atrial paced rhythm is due to reduced synchronization of endocardial activation secondary to ectopic entry of impulses into the HPS network and inability to take advantage of the branching structure of the HPS. Therefore, in addition to transseptal conduction delay, reduced synchronization of endocardial activation is another potential mechanism for QRSD widening.     

Plasmakinetic prostate resection in the treatment of benign prostate hyperplasia: Results of 1-year follow up

AIM: In our randomized prospective study, we aimed to evaluate the efficiency of plasmakinetic resection of prostate (PKRP) by comparing the preoperative and postoperative results of the transurethral resection of prostate (TURP) and PKRP techniques which we administered in patients with benign prostate hyperplasia (BPH) in our clinic. METHODS: Of 57 patients for whom we thought an operative intervention was necessary, 30 cases in the first group had a TURP and 24 cases in the second group had a PKRP. International prostate symptom scores (I-PSS), uroflowmetry, measurement of residual urine amount and ultrasonography were performed for each patient both preoperatively and postoperatively (first month and first year). Operation times, urethral catheterization times, preoperative and postoperative Hb, Htc and serum Na values of the patients were compared and the complications of the groups were also compared. RESULTS: On first month and first year follow up between the groups, there was no significant statistical difference in I-PSS, maximum flow rate, average flow, residual urine and size of the prostate. The decrease in serum Na level was found to be significantly higher in the TURP group (P < 0.05). The operation times were not significantly different between the groups. While the postoperative catheterization time was 75.7 h in TURP group, it was found to be 42 h in PKRP group and it was clear that catheterization time was significantly shorter (P < 0001). CONCLUSION: It is obvious that PKRP is as efficient as TURP and it has a similar morbidity. In our opinion, PKRP makes a promising treatment for BPH with its advantages, such as early removal of postoperative urethral catheter, a shorter hospital stay and the absence of TUR syndrome risk.