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Anand Kumar Singh Manindra Nath Tiwari Om Prakash Mahendra Pratap Singh 《Current Neuropharmacology》2012,10(1):64-71
Cypermethrin, a class II pyrethroid pesticide, is used to control insects in the household and agricultural fields. Despite beneficial roles, its uncontrolled and repetitive applications lead to unintended effects in non-target organisms. Cypermethrin crosses the blood-brain barrier and induces neurotoxicity and motor deficits. Cypermethrin prolongs the opening of sodium channel, a major site of its action, leading to hyper-excitation of the central nervous system. In addition to sodium channel, cypermethrin modulates chloride, voltage-gated calcium and potassium channels, alters the activity of glutamate and acetylcholine receptors and adenosine triphosphatases and induces DNA damage and oxidative stress in the neuronal cells. Cypermethrin also modulates the level of neurotransmitters, including gamma-aminobutyric acid and dopamine. It is one of the most commonly used pesticides in neurotoxicology research not only because of its variable responses depending upon the doses, time and routes of exposure and strain, age, gender and species of animals used across multiple studies but also owing to its ability to induce the nigrostriatal dopaminergic neurodegeneration. This article describes the effect of acute, chronic, developmental and adulthood exposures to cypermethrin in experimental animals. The article sheds light on cypermethrin-induced changes in the central nervous system, including its contribution in the onset of specific features, which are associated with the nigrostriatal dopaminergic neurodegeneration. Resemblances and dissimilarities of cypermethrin-induced nigrostriatal dopaminergic neurodegeneration with sporadic and chemicals-induced disease models along with its advantages and pitfalls are also discussed. 相似文献
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Human hydatid disease or cystic echinococcosis (CE), caused by the larval form of cestode Echinococcus granulosus still continues to a common problem in health care environments as different as Europe/North America and resource poor countries of the South America and the East. The Liver is the most frequently parasatized organ in humans. While ultrasonography remains the main diagnostic tool, computed tomography and serology improve the accuracy of diagnosis in Liver hydatid cysts (LHC). Although surgery is the only modality applicable over the entire spectrum of the disease, systemic chemotherapy and percutaneous drainage have evolved as alternative therapies in the last three decades. Various laparoscopic techniques have also been described for safe and optimal management of this entity. In this paper, we review the current management procedures of LHC with particular emphasis on the evidence base and setting specific problems. 相似文献
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Derek E. Byers Jennifer Alexander-Brett Anand C. Patel Eugene Agapov Geoffrey Dang-Vu Xiaohua Jin Kangyun Wu Yingjian You Yael Alevy Jean-Philippe Girard Thaddeus S. Stappenbeck G. Alexander Patterson Richard A. Pierce Steven L. Brody Michael J. Holtzman 《The Journal of clinical investigation》2013,123(12):5410
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Ethan J. Halpern Jacob P. Deutsch Maria M. Hannaway Adrian T. Estepa Anand S. Kenia Kenneth J. Neuburger David C. Levin 《The American journal of emergency medicine》2013,31(10):1479-1485
ObjectiveThe objective of the study is to evaluate cardiac risk factors and risk scores for prediction of coronary artery disease (CAD) and adverse outcomes in an emergency department (ED) population judged to be at low to intermediate risk for acute coronary syndrome.MethodsInformed consent was obtained from consecutive ED patients who presented with chest pain and were evaluated with coronary computed tomography angiography (cCTA). Cardiac risk factors, clinical presentation, electrocardiogram, and laboratory studies were recorded; the Thrombolysis in Myocardial Infarction (TIMI) and Global Registry of Acute Coronary Events (GRACE) scores were tabulated. Coronary computed tomography angiography findings were rated on a 6-level plaque burden scale and classified for significant CAD (stenosis ≥ 50%). Adverse cardiovascular outcomes were recorded at 30 days.ResultsAmong 250 patients evaluated by cCTA, 143 (57%) had no CAD, 64 (26%) demonstrated minimal plaque (< 30% stenosis), 26 (10%) demonstrated mild plaque (< 50% stenosis), 9 (4%) demonstrated moderate single vessel disease (50%-70% stenosis), 2 (1%) demonstrated moderate multivessel disease, and 6 (2%) demonstrated severe disease (> 70% stenosis). Six patients developed adverse cardiovascular outcomes. Among traditional cardiac risk factors, only age (older) and sex (male) were significant independent predictors of CAD. Correlation with CAD was poor for the TIMI (r = 0.12) and GRACE (r = 0.09-0.23) scores. The TIMI and GRACE scores were not useful to predict adverse outcomes. Coronary computed tomography angiography identified severe CAD in all subjects with adverse outcomes.ConclusionAmong ED patients who present with chest pain judged to be at low to intermediate risk for acute coronary syndrome, traditional risk factors are not useful to stratify risk for CAD and adverse outcomes. Coronary computed tomography angiography is an excellent predictor of CAD and outcome. 相似文献
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