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Although amiodarone is the most commonly prescribed anti-arrhythmic drug, its use is limited by serious toxicities, including optic neuropathy. Current reports of amiodarone-associated optic neuropathy identified from the Food and Drug Administration's Adverse Event Reporting System and published case reports were reviewed. A total of 296 reports were identified: 214 from the Adverse Event Reporting System, 59 from published case reports, and 23 from adverse events reports for patients enrolled in clinical trials. Mean duration of amiodarone therapy before vision loss was 9 months (range 1-84 months). Insidious onset of amiodarone-associated optic neuropathy (44%) was the most common presentation, and nearly one third were asymptomatic. Optic disk edema was present in 85% of cases. Following drug cessation, 58% had improved visual acuity, 21% were unchanged, and 21% had further decreased visual acuity. Legal blindness (<20/200) was noted in at least one eye in 20% of cases. Close ophthalmologic surveillance of patients during the tenure of amiodarone administration is warranted.  相似文献   
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Multiple idiopathic cervical resorption is an uncommon condition, the etiology of which remains unknown. The case of a 36-year-old woman with idiopathic resorption in the cervical areas of multiple teeth is presented. Her medical history was noncontributory, but her dental history was valuable in reaching a diagnosis. Hematologic and endocrinal investigations were unremarkable, but a computed tomography scan revealed relevant information. The progression of the lesion and involvement of multiple teeth without any pattern or chronology are challenges faced when diagnosing and treating this condition.  相似文献   
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Aging is a debilitating process often associated with chronic diseases such as diabetes, cardiovascular and neurodegenerative diseases like Alzheimer's disease (AD). AD occurs at a very high incidence posing a huge burden to the society. Model organisms such as C. elegans become essential to understand aging or lifespan extension - the etiology, molecular mechanism and identification of new drugs against age associated diseases. The AD model, manifesting Aβ proteotoxicity, in C. elegans is well established and has provided valuable insights. Earlier, we have reported that Reserpine, an FDA-approved antihypertensive drug, increases C. elegans lifespan with a high quality of life and ameliorates Aβ toxicity in C. elegans. But reserpine does not seem to act through the known lifespan extension pathways or inhibition of its known target, vesicular monoamine transporter, VMAT. Reserpine's mode of action and the pathways it activates are not known. Here, we have evaluated the presynaptic neurotransmitter(s) release pathway and identified acetylcholine (ACh) as the crucial player for reserpine's action. The corroborating evidences are: i) lack of lifespan extension in the ACh loss of function (hypomorphic) - synthesis (cha-1) and transport (unc-17) mutants; ii) mitigation of chronic aldicarb effect; iii) lifespan extension in dopamine (cat-2) and dopamine and serotonin (bas-1) biosynthetic mutants; iv) no rescue from exogenous serotonin induced paralysis in the AD model worms; upon reserpine treatment. Thus, modulation of acetylcholine is essential for reserpine's action.  相似文献   
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In the present report, an environmentally benign magnetically recoverable nickel(ii)-based nanoreactor as a heterogeneous catalyst has been developed via a template free approach. The catalytic performance of the synthesized catalyst is assessed in the confined oxidative coupling of arenethiols with arylhydrazines to form unsymmetrical diaryl sulfides under aerobic conditions. The salient features of our protocol include oxidant- and ligand-free conditions, use of water as a green solvent, room temperature and formation of nitrogen and water as the only by-products. Moreover, a broad range of functional groups are tolerated well and provide the corresponding diaryl sulfides in moderate to good yields. Moreover, the heterogeneous nature of the catalyst permits facile magnetic recovery and reusability for up to seven runs, making the present protocol highly desirable from industrial and environmental standpoints.

An environmentally benign nickel(ii)-based magnetic nanoreactor has been developed for oxidative coupling of arenethiols with arylhydrazines to form unsymmetrical diaryl sulfides in water at room temperature.  相似文献   
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