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3-Phenoxybenzoic acid (3-PBA) and 4-hydroxy-3-phenoxybenzoic acid (OH-PBA) are the two common metabolites for most pyrethroid insecticides. A rapid, sensitive, and eco-friendly method has been developed based on ultrasound-assisted dispersive liquid–liquid microextraction (DLLME) coupled to large volume injection–gas chromatography–tandem mass spectrometry for the simultaneous determination of pyrethroid metabolites in rat brain treated with cypermethrin (CYP). Brain samples were homogenized in methanol (disperser solvent) followed by derivatization with methyl chloroformate (MCF) and extraction using DLLME. Factors that influence the extraction and derivatization efficiency such as type and volume of extraction and disperser solvent, sonication time, pH, ionic strength, and volumes of MCF and pyridine were optimized. Under optimized conditions, the limits of detection were 1 and 4 ng/g for 3-PBA and OH-PBA, respectively. Mean recoveries of pyrethroid metabolites in rat brain were in the range of 83–95 %. The developed method was successfully applied for determination of 3-PBA and OH-PBA in brain samples of CYP-treated rats. The developed method can be adopted for rapid and sensitive analysis of pyrethroid metabolites in toxicological and forensic laboratories.  相似文献   
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Myasthenia gravis (MG) is a disease that affects the neuro-muscular junction resulting in classical symptoms of variable muscle weakness and fatigability. It is called the great masquerader owing to its varied clinical presentations. Very often, a patient of MG may present to the ophthalmologist given that a large proportion of patients with systemic myasthenia have ocular involvement either at presentation or during the later course of the disease. The treatment of ocular MG involves both the neurologist and ophthalmologist. Thus, the aim of this review was to highlight the current diagnosis, investigations, and treatment of ocular MG.  相似文献   
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In the year 2012 leaf curl disease was observed on Marigold (Tagetes patula) in Lakshmangrh, Sikar province of India. Affected plants were severely stunted with apical leaf curl and crinkled leaves, symptoms typical of begomovirus infection. This is the first report of complete nucleotide sequence of a begomovirus associated with satellites molecules infecting a new host Tagetes patula in India.  相似文献   
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Type 2 diabetes mellitus (T2DM) accounts for >90% of the cases of diabetes in adults. Resistance to insulin action is the major cause that leads to chronic hyperglycemia in diabetic patients. T2DM is the consequence of activation of multiple pathways and factors involved in insulin resistance and β-cell dysfunction. Also, the etiology of T2DM involves the complex interplay between genetics and environmental factors. This interplay can be governed efficiently by lifestyle modifications to achieve better management of diabetes. The present review aims at discussing the major factors involved in the development of T2DM that remain unfocussed during the anti-diabetic therapy. The review also focuses on lifestyle modifications that are warranted for the successful management of T2DM. In addition, it attempts to explain flaws in current strategies to combat diabetes. The employability of phytoconstituents as multitargeting molecules and their potential use as effective therapeutic adjuvants to first line hypoglycemic agents to prevent side effects caused by the synthetic drugs are also discussed.  相似文献   
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The mitochondrial permeability transition (mPTP) is a key feature of cardiac cell death in ischaemia‐reperfusion injury (I/R). The mPTP blocker, cyclosporine A (CsA), has been shown to give protection against reperfusion‐induced myocardial necrosis and troubles generated by acute coronary artery repermeabilization. Nevertheless, the results of the CIRCUS trial (Does Cyclosporine Improve Clinical Outcome in ST‐Elevation Myocardial Infarction Patients) seem to go against this hypothesis. Pharmacological reasons linked to CsA pharmacokinetics and pharmacodynamics could be suggested. First, it could be explained by a limited diffusion of the drug in the area at risk, due to the only inclusion of patients with a TIMI 0 or 1 coronary blood flow in the anterior territory and the absence of collateral perfusion. Second, to explain a low tissue diffusion of the compound, blood cell capture and high metabolism could be suggested. Moreover, CsA is highly metabolized by cytochrome P450 3A4 (CYP3A4), a polymorphic enzyme leading to variations of Cmax and AUC between 10–20% in patients using CsA. Finally, CsA blocks calcineurin, a protein implied in I/R damage but calcineurin inhibition could contribute to protection towards I/R damage only when Rcan1, a calcineurin natural inhibitor, expression is low. The results of the CIRCUS trial are disappointing and could contribute to the withdrawal of the mPTP blockade pharmacological strategy as a way to protect the myocardium from I/R lesions. Nevertheless, many pharmacological insights could have contributed to an increased variability and, as a consequence, an important reduction of the pharmacological power of the study.  相似文献   
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Many therapies with potential for treatment of brain injury have been investigated. Few types of cells have spurred as much interest and excitement as stem cells over the past few decades. The multipotentiality and self-renewing characteristics of stem cells confer upon them the capability to regenerate lost tissue in ischemic or degenerative conditions as well as trauma. While stem cells have not yet proven to be clinically effective in many such conditions as was once hoped, they have demonstrated some effects that could be manipulated for clinical benefit. The various types of stem cells have similar characteristics, and largely differ in terms of origin; those that have differentiated to some extent may exhibit limited capability in differentiation potential. Stem cells can aid in decreasing lesion size and improving function following brain injury.  相似文献   
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