牛磺酸对染铅大鼠海马一氧化氮合酶活力的影响

目的　探讨牛磺酸拮抗铅损害学习记忆能力的作用。方法　采用NADPH d组织化学法 ,研究饮用含不同剂量铅 (0 .0 11、0 .110g L)的水和含不同剂量牛磺酸 (5、10g kg)的饲料喂养的大鼠海马一氧化氮合酶 (NOS)阳性神经元数量的变化。结果　 10g kg的牛磺酸饲料能明显增加染铅大鼠海马CA1区和齿状回NOS阳性神经元的数量。低铅水高牛磺酸饲料组NADPH d阳性神经数量在CA1区为 5 1.80± 4 .6 8,在齿状回为 4 7.4 0± 4 .2 0 ,较低铅水普通饲料组的CA1区 (4 1.2 0± 5 .32 )和齿状回 (39.87± 3.81)明显增多 ,差异有显著性 (P <0 .0 5 )。结论　牛磺酸对铅损害学习记忆能力有较明显的拮抗作用。     

New Electrocardiographic Features in Brugada Syndrome

Brugada syndrome is a genetically determined familial disease with autosomal dominant transmission and variable penetrance, conferring a predisposition to sudden cardiac death due to ventricular arrhythmias. The syndrome is characterized by a typical electrocardiographic pattern in the right precordial leads. This article will focus on the new electrocardiographic features recently agreed on by expert consensus helping to identify this infequent electrocardiographic pattern.     

In vitro modeling accurately predicts cardiac lead fracture at 10 years

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Nervous system effects in rats on subacute exposure by lead-containing nanoparticles via the airways

Context and objective: Lead (Pb) is a heavy metal harmful for human health and environment. From leaded gasoline (still used in certain countries), and in Pb processing and reprocessing industries, airborne particles are emitted which can be inhaled. In such exposure, the size of particles entering the airways is crucial. The nervous system is a primary target for Pb, and consequences like occupational neuropathy and delayed mental development of children are well-known. The aim of this work was to investigate the neurotoxicity of Pb nanoparticles (NPs) applied into the airways of rats.

Methods: Nano-sized lead oxide particles (mean diameter ca. 20?nm) were suspended in distilled water and instilled into the trachea of adult male Wistar rats (in doses equivalent to 2 and 4?mg/kg Pb), 5 times a week for 3 and 6 weeks. At the end, open field motility was tested, then central and peripheral nervous activity was recorded in urethane anesthesia.

Results and conclusion: The treated rats’ body weight gain was significantly lower than that of the controls from the 3rd week onwards, and the weight of their lungs was significantly increased. Horizontal motility increased while vertical motility decreased. Spontaneous cortical activity was shifted to higher frequencies. The somatosensory cortical evoked potential showed increased latency and decreased frequency-following ability, and similar alterations were seen in the tail nerve. Significant Pb deposition was measured in blood, brain, lung and liver samples of the treated rats. The experiments performed seem to constitute an adequate model of the human effects of inhaled Pb NPs.     

Potential health risks to adults and children in the UK from exposure to dietary lead in gamebirds shot with lead ammunition

We estimate potential risks to human health in the UK from dietary exposure to lead from wild gamebirds killed by shooting. The main source of exposure to lead in Europe is now dietary. We used data on lead concentrations in UK gamebirds, from which gunshot had been removed following cooking to simulate human exposure to lead. We used UK food consumption and lead concentration data to evaluate the number of gamebird meals consumed weekly that would be expected, based upon published studies, to result in changes, over and above those resulting from exposure to lead in the base diet, in intelligence quotient (IQ), Systolic Blood Pressure and chronic kidney disease (CKD) considered in a recent opinion of the European Food Safety Authority (EFSA) to be significant at a population level and also in SAT test scores and in rates of spontaneous abortion. We found the consumption of <1 meal of game a week may be associated with a one point reduction in IQ in children and 1.2–6.5 gamebird meals per week may be associated with the other effects. These results should help to inform the development of appropriate responses to the risks from ingesting lead from ammunition in game in the UK and European Union (EU).     

Tremor and Quality of Life in Patients With Advanced Essential Tremor Before and After Replacing Their Standard Deep Brain Stimulation With a Directional System

ObjectivesPatients with essential tremor treated with thalamic deep brain stimulation may experience increased tremor with the progression of their disease. Initially, this can be counteracted with increased stimulation. Eventually, this may cause unwanted side-effects as the circumferential stimulation from a standard ring contact spreads into adjacent regions. Directional leads may offer a solution to this clinical problem. We aimed to compare the ability of a standard and a directional system to reduce tremor without side-effects and to improve the quality of life for patients with advanced essential tremor.Materials and MethodsSix advanced essential tremor patients with bilateral thalamic deep brain stimulation had their standard system replaced with a directional system. Tremor rating scale scores were prospectively evaluated before and after the replacement surgery. Secondary analyses of quality of life related to tremor, voice, and general health were assessed.ResultsThere was a significantly greater reduction in tremor without side-effects (p = 0.017) when using the directional system. There were improvements in tremor (p = 0.031) and voice (p = 0.037) related quality of life but not in general health for patients using optimized stimulation settings with the directional system compared to the standard system.ConclusionsIn this cohort of advanced essential tremor patients who no longer had ideal tremor reduction with a standard system, replacing their deep brain stimulation with a directional system significantly improved their tremor and quality of life. Up-front implantation of directional deep brain stimulation leads may provide better tremor control in those patients who progress at a later time point.     

Electrical abnormalities with St. Jude/Abbott pacing leads: A systematic review and meta-analysis

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The Presence of Giant Epsilon Waves in a Patient with Arrhythmogenic Right Ventricular Cardiomyopathy

Epsilon wave, which is a major diagnosis criterion for arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVD/C), is defined as small amplitude potentials. The present case is a 49‐year‐old man with a history of syncope and palpitations for 6 months. The ECG documented ventricular tachycardia (VT) when the patient has palpitations. However, there has been a giant epsilon wave in sinus rhythm. Electroanatomic mapping also has a prominent double potential identified on ABL catheter. The amplitude of epsilon wave reached 0.9 mV, which might be the maximum epsilon wave until now.     

Blood lead levels and risk factors in young children in France, 2008–2009

BackgroundThe exposure of children to lead has decreased in recent years, thanks notably to the banning of leaded gasoline. However, lead exposure remains a matter of public health concern, because no toxicity threshold has been observed, cognitive effects having been demonstrated even at low levels. It is therefore important to update exposure assessments. A national study was conducted, in 2008–2009, to determine the blood lead level (BLL) distribution in children between the ages of six months and six years in France. We also assessed the contribution of environmental factors.MethodsThis cross-sectional survey included 3831 children recruited at hospitals. Two-stage probability sampling was carried out, with stratification by hospital and French region. Sociodemographic characteristics were recorded, and blood samples and environmental data were collected by questionnaire. Generalized linear model and quantile regression were used to quantify the association between BLL and environmental risk factors.ResultsThe geometric mean BLL was 14.9 μg/l (95% confidence interval (CI) = [14.5–15.4]) and 0.09% of the children (95% CI = [0.03–0.15]) had BLLs exceeding 100 μg/l, 1.5% (95% CI = [0.9–2.1] exceeding 50 μg/l. Only slight differences were observed between French regions. Environmental factors significantly associated with BLL were the consumption of tap water in homes with lead service connections, peeling paint or recent renovations in old housing, hand-mouth behavior, passive smoking and having a mother born in a country where lead is often used.ConclusionsIn children between the ages of one and six years in France, lead exposure has decreased over the last 15 years as in the US and other European countries. Nevertheless still 76,000 children have BLL over 50 μg/l and prevention policies must be pursued, especially keeping in mind there is no known toxicity threshold.