Metastatic rhabdomyosarcoma of the thyroid gland, a case report

The thyroid gland is a known but an unusual site for metastatic tumors from various primary sites. Despite the fact that it is one of the largest vascular organs in the body, clinical and surgical cases have given an incidence of 3?% of secondary malignances of the organ. Nevertheless, thyroid metastases are not an exceptional finding at autopsy, they are encountered in 2?% to 24?% of the patients with malignant neoplasm. Soft tissue sarcomas metastatic to the thyroid are extremely rare as the majority of thyroid metastasis are caused by tumors of the kidneys, lungs, mammary glands, ovaries , and colon or by melanomas. We report a case of 22-years-old woman with right leg rhabdomyosarcoma metastatic to the thyroid gland.     

Epileptic Discharges in a Mammillary Body of a Patient with Refractory Epilepsy

Objectives. To document epileptiform discharges recorded within a mammillary body (MB) of a patient with chronic refractory epilepsy (CRE). Materials and Methods. A 37‐year‐old man, whose epilepsy was not controlled by medication or vagus nerve stimulation, was enrolled in a study of the effects of deep brain stimulation of the MB and mammillothalamic tract (MTT) in CRE. Surface and deep EEG recordings were obtained for 3 days before implantation of the macroelectrodes and for 4 days after implantation of the macroelectrodes but before implantation of the stimulator battery. Results. Paroxysmal epileptiform discharges were recorded in the right MB while other surface and deep recordings, in particular from the right MTT, were silent. When these discharges were longer than 100 sec, they spread to the right MTT area and then to the left MB and MTT area. Simultaneously, the patient became agitated and confused. Conclusions. This original observation indicates that subcortical neuronal structures, such as the MB, may sustain epileptiform discharges in humans.     

Effect of different resin luting cements on the marginal fit of lithium disilicate pressed crowns

Statement of problem

The vertical marginal discrepancy of restorations can increase upon cementation, and poor marginal fit can lead to cement dissolution, marginal discoloration, microleakage, and secondary caries. The amount of increase is related to the type of luting cement used, but how lithium disilicate pressed crowns are affected by different resin cements is unclear.

Rational design of a polypyrrole-based competent bifunctional magnetic nanocatalyst

The combination of conducting polymers with semiconductors for the fabrication of organic/inorganic hybrid nanocatalysts is one of the most promising research areas for many applications. In this work, the synthesized nanocomposite combines several advantages such as the photoresponse shift from the UV region toward visible light by narrowing the band gap of the semiconductor, magnetic separation ability and dual applications including the catalytic reduction of p-nitrophenol (PNP) and the photocatalytic degradation of methylene blue (MB) dye. In addition to the core magnetite nanoparticles (NPs), the synthesized nanocomposite contains polypyrrole (PPY) and TiO₂ shells that are decorated with silver metal NPs to prevent electron–hole recombination and to enhance the catalytic performance. Indeed, the catalytic PNP reduction experiments reveal that the synthesized nanocomposite exhibits significantly high catalytic activity with a rate constant of 0.1169 min⁻¹. Moreover, the photocatalytic experiments show that the synthesized nanophotocatalyst has a boosting effect toward MB dye degradation under normal daytime visible light irradiation with a rate constant of 6.38 × 10⁻² min⁻¹. The synergetic effect between silver NPs, PPY and TiO₂ is thought to play a fundamental role in enhancing the photocatalytic activity.

An efficient method to synthesize a magnetic nanocomposite with dual catalytic activities with a synergetic effect between Ag nanoparticles, polypyrrole and TiO₂ is described.     

The Effect of a Statewide Smoking Ordinance on Acute Myocardial Infarction Rates

Background

Public smoking ordinances may reduce acute myocardial infarction events. Most studies assessed small communities with reported reductions as high as 40%. No reduction or smaller reductions were found in countrywide studies; less is known about the impact of statewide ordinances. We previously demonstrated identical 27% reductions in acute myocardial infarction hospitalizations in 2 Colorado communities after enactment of strict smoking ordinances. Subsequently, on July 1, 2006, a statewide ordinance went into effect. We sought to determine the impact of this legislation on acute myocardial infarction hospitalization rates.

Methods

Hospital admissions for a primary acute myocardial infarction diagnosis were examined from 2000 to 2008. Poisson regression models were fit to the monthly events from January 1, 2000, to March 31, 2008. The final model included a quadratic trend over time, harmonic terms, and a post-ordinance effect. The model was adjusted temporally for population changes, using population estimates as an offset variable.

Results

A total of 58,399 unique acute myocardial infarctions were recorded during the study period. No significant reduction in acute myocardial infarction rates was observed post-ordinance (relative risk, 1.059; 95% confidence interval, 0.993-1.131). However, a steep decline in acute myocardial infarction rates was noted from 2000 to 2005 just before enactment. There were 11 strict, local smoking ordinances in effect within Colorado before enactment of the statewide ordinance. After excluding these communities, the findings were similar (relative risk, 1.038; 95% confidence interval, 0.971-1.11).

Conclusions

Although local smoking ordinances in Colorado previously suggested a reduction in acute myocardial infarction hospitalizations, no significant impact of smoke-free legislation was demonstrated at the state level, even after accounting for preexisting ordinances.     

The Left Atrial Appendage: Target for Stroke Reduction in Atrial Fibrillation

A patient with atrial fibrillation (AF) has a greater than 5% annual risk of major stroke, a 5-fold increase compared to the general population. While anticoagulation remains the standard stroke prevention strategy, the nature of lifelong anticoagulation inevitably carries an increased risk of bleeding, increased stroke during periods of interruption, increased cost, and significant lifestyle modification. Many patients with atrial fibrillation have had their left atrial appendage (LAA) ligated or excised by surgeons during cardiac surgery, a decision based largely on intuition and with no clear evidence of efficacy in stroke risk reduction. The observation that 90% of the thrombi found in nonvalvular AF patients and 57% found in valvular AF are in the LAA, triggered significant interest in the LAA as a potential therapeutic target. Until recently, the results were inconsistent, and high rates of incomplete occlusions precluded the medical community from confirming a definite relationship between LAA and stroke. As a result, anticoagulation is still the recommended first-line stroke risk reduction in AF, and the American College of Cardiology/American Heart Association guidelines recommend LAA exclusion only with surgical ablation of AF or in the context of concomitant mitral valve surgery.A handful of devices have been developed for LAA exclusion. This includes percutaneous options such as WATCHMAN™ Left Atrial Appendage Closure Device (Boston Scientific Corporation, Marlborough, MA), hybrid epicardial devices such as the LARIAT Suture Delivery Device (SentreHEART, Inc., Redwood City, CA), and epicardial surgical devices such as AtriClip® LAA Occlusion System (AtriCure, Inc., West Chester, OH). Studies of the Watchman device have shown noninferiority to Warfarin in stroke prevention and this device has recently gained approval from the U.S. Food and Drug Administration (FDA) following lengthy delays due to safety concerns. The Lariat device, which received 510K clearance by the FDA for tissue approximation but not LAA exclusion, has been the target of significant criticism due to serious procedural safety concerns and high incomplete closure rates. The surgical AtriClip has been FDA approved since 2009 and is currently the most widely used LAA exclusion device placed through an epicardial approach. Small studies have shown excellent reliability and success of complete LAA closure with the AtriClip device, which is implanted through an epicardial approach. Currently, we are conducting a multicenter trial to demonstrate the stroke prevention potential of this epicardial device through a short (45 minute), stand-alone, minimally invasive procedure in lieu of lifelong anticoagulation in patients at high risk of bleeding.