Effect of lead trajectory on the response of essential head tremor to deep brain stimulation

BackgroundEssential tremor (ET) is one of the most common movement disorders. Normally ET affects the distal upper extremities, but it can also be accompanied by midline symptoms. Ventralis intermedius (VIM) thalamic deep brain stimulation (DBS) has been shown to be effective in reducing hand tremor, but its effects on head tremor have been inconsistent.MethodsTwenty-nine DBS patients with a diagnosis of ET met inclusion criteria. All implantations targeted VIM. The factors examined included age, gender, disease duration, presence or absence of head tremor, handedness, and the Fahn-Tolosa-Marin rating scale (TRS). This analysis specifically focused on TRS head tremor sub-scores at baseline, 6 months and 12 months post-DBS. Additionally, DBS lead entry angles were examined.ResultsTwenty-three ET patients underwent unilateral DBS and six underwent staged bilateral DBS. At both 6 and 12 months following DBS, stimulation resulted in diminished head tremor (ON vs OFF; p < 0.0001). The most important predictor of head tremor suppression was the entry angle of the DBS lead in the sagittal projection relative to the AC–PC axial plane (AC–PC angle). Head tremor reduction was greater among more vertical AC–PC angles.ConclusionA more vertical AC–PC angle of the DBS lead trajectory was associated with improved head tremor suppression. Further studies will be necessary to confirm this potentially important finding.     

Immunohistochemical evaluation of the effect of lead exposure on subcommissural organ innervation and secretion in Shaw's Jird (Meriones shawi)

The secretory activity of subcommissural organ cells is controlled by various extrinsic and intrinsic factors. Lead has been recognised as a neurotoxic heavy metal, since it induces morphological and functional abnormalities in the brain. In this work, we examined the effect of lead exposure on the subcommissural organ (SCO), a brain gland known by its secretion of Reissner's fiber (RF) in cerebro-spinal fluid. Glycoprotein secretion and serotonin (5HT) innervation of the SCO was examined after acute and chronic lead exposures in the sub-desert rodent Meriones shawi. Lead exposures were achieved by, respectively, intra-peritoneal injection of 25 mg/kg body weight of lead acetate for 3 days and 0.5% of lead acetate in the drinking water over 4 months until adult age. 5HT and RF immunolabeling in the SCO revealed several serotoninergic fibers reaching the SCO and abundant secretory material. An increase in both 5HT innervation and secretory material of the SCO was recorded after both acute and chronic lead exposure. These results show that lead exposure affects the serotonergic innervation of the SCO. Moreover, the enhancement of SCO secretion suggests a role of this gland in neuroprotection and lead detoxification of the brain in Meriones shawi.     

Mitigative role of garlic and vitamin E against cytotoxic,genotoxic, and apoptotic effects of lead acetate and mercury chloride on WI-38 cells

Background

Lead acetate (Led) and mercury chloride (Mer) represent important ecological and public health concerns due to their hazardous toxicities. Naturally found products play a vital role in chemopreventive agent innovation. The current study aimed to assess the modifying effect of garlic (Gar) and/or vitamin E (Vit E) against the half-maximal inhibitory concentration (IC50) Led and/or Mer-induced cytotoxic, genotoxic and apoptotic effects.

Evidence that birth weight is decreased by maternal lead levels below 5 μg/dl in male newborns

To assess the association between birth weight and maternal blood lead (BPb) levels, 386 pregnant women and their newborn offspring were surveyed. Mean ± SD (range) maternal BPb concentrations were 0.98 ± 0.55 (0.10–3.99), 0.92 ± 0.63 [<0.09 (limit of quantification)–3.96], and 0.99 ± 0.66 (<0.09–3.96) μg/dl at 12, 25 and 36 weeks’ gestation, respectively. Mean ± SD (range) gestational age at delivery was 38.9 ± 1.3 (35–41) weeks. In male newborns, a significant correlation between birth weight and logBPb at 12 weeks’ gestation was observed (Spearman's rank correlation coefficient = −0.145, p < 0.05). Multiple regression analysis indicated that birth weight was significantly inversely associated with logBPb at 12 weeks’ gestation, controlling for possible confounding variables. These results suggest that low-level exposure to lead in early gestation could be a risk factor for reduced birth weight in male offspring.     

Increased urinary cobalt and whole blood concentrations of cadmium and lead in women with uterine leiomyomata: Findings from the ENDO Study

Multiple trace elements have estrogen receptor activity, but the association of these elements with uterine leiomyoma has not been defined. A cohort of 473 women aged 18–44 undergoing surgery for benign gynecologic indications provided whole blood and urine specimens for trace element analysis, which was performed by inductively coupled plasma mass spectrometry. Twenty elements were analyzed in blood and 3 in urine. The surgeon documented whether fibroids were present. Geometric mean concentrations were compared between women with and without fibroids, and logistic regression models were generated to assess the impact of the concentration of each trace element on the odds of fibroids. In multivariate regressions, odds of a fibroid diagnosis were higher with increased whole blood cadmium (AOR 1.44, 95% CI 1.02, 2.04) and lead (AOR 1.31 95% CI 1.02, 1.69), and urine cobalt (AOR 1.31, 95% CI 1.02, 1.70). Urinary cadmium and lead were not related to fibroid diagnosis. Increased exposure to trace elements may contribute to fibroid growth, and fibroids may serve as a reservoir for these elements. Differences between urinary and whole blood findings merit further investigation, as urinary cadmium has been considered a superior marker of exposure.     

铅和噪声联合作用对作业工人血SOD、MDA含量的影响

目的 探讨铅和噪声联合作用对工人的血清超氧化物歧化酶（SOD）、丙二醛（MDA）含量的影响.方法 选择年龄、工龄及接触噪声强度相近的A（铅和噪声联合作用组）、B（单纯噪声组）两组工人,测定血SOD、MDA含量,同时测定血铅含量,并比较两组数据差异.结果 A、B两组工人血SOD值分别为（65.2±16.3） U/ml、（63.8±13.9） U/ml,两组工人血SOD值无明显差异（P＞0.05）;A、B两组工人血MDA含量分别为（6.81±3.12）nmol/ml、（5.02±2.36）nmol/ml,两组工人血MDA含量差异有统计学意义（P＜0.05）.结论 铅和噪声联合作用可加重机体自由基损害和脂质过氧化.     

Ⅰ和aVF导联联合Ⅱ导联法与传统Ⅰ和Ⅲ导联法判断QRS平均心电轴的比较

目的比较Ⅰ和aVF导联目测判断QRS平均心电轴与Ⅰ和Ⅲ导联判断电轴的优势。方法采用整群抽样法抽取兰州大学第二临床医学院2015级临床医学生,分为研究组和对照组,研究组用导联Ⅰ和aVF判断电轴,对照组用导联Ⅰ和Ⅲ判断电轴。判断标准依据心电图机系统化数据为参考结果。结果应用导联Ⅰ和aVF判断其中3个象限的心电轴快速准确;当电轴在“left”象限时,需要联合Ⅱ导联正负相判断。Ⅰ和Ⅲ导联误判率相对较高。结论用Ⅰ和aVF导联判断QRS平均心电轴快速准确,可用于临床。     

双心腔主动电极起搏与心房被动心室主动电极起搏的对比研究

目的:观察心房心室双螺旋主动电极在双腔心脏起搏器植入术中的有效性和安全性。方法:回顾性将90例符合双腔起搏器植入指征的患者分为心房心室双螺旋主动电极组(双螺旋电极组42例)与心房被动电极、心室螺旋主动电极组(单螺旋电极组48例)。观察2组术中及术后随访情况。结果:2组均成功植入起搏器及起搏电极。双螺旋电极组中1例孕妇零射线下完成双螺旋电极及起搏器植入;4例永存左上腔静脉患者在左侧锁骨下完成双螺旋电极及起搏器植入。双螺旋电极组和单螺旋电极组的手术时间及射线时间无显著差别,双螺旋电极组术后卧床时间显著缩短[(4.2±1.5)h vs(56.3±22.5)h,P0.05]。单螺旋电极组术中出现心房电极导线脱位3例,双螺旋电极组未见导线移位、心肌穿孔及心包填塞等情况。术后随访,2组均无电极脱落和起搏阈值升高。结论:心房心室双螺旋主动电极在双腔心脏起搏器植入术中安全可行,并不增加手术时间和射线时间,特别是应用于心腔结构异常和特殊患者,显著增加手术成功率。