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Electrochemical NAD+ reduction is a promising method to regenerate NADH for enzymatic reactions. Many different electrocatalysts have been tested in the search for high yields of the 1,4-isomer of NADH, the active NADH, but aside from electrode material, other system parameters such as pH, electrode potential and educt concentration also play a role in NADH regeneration. The effect of these last three parameters and the mechanisms behind their influence on NADH regeneration was systematically studied and presented in this paper. With percentages of active NADH ranging from 10% - to 70% and faradaic efficiencies between 1% and 30%, it is clear that all three system parameters drastically affect the reaction outcome. The optimised reaction conditions were applied to test the consumption of the regenerated NADH by an enzymatic reaction. Electrochemical NAD + reduction in the presence of pyruvate and lactate dehydrogenase revealed that the 1,4-isomer of NADH, the physiological substrate of oxidoreductases, accounted for around 45% of the detectable electrochemically regenerated NADH.

El nódulo calcificado se ha establecido como el último sustrato subyacente en el síndrome coronario agudo; no obstante, el calcio está presente frecuentemente en otros escenarios agudos. La tomografía de coherencia óptica (OCT) ha logrado identificar en este sentido 3 patrones distintos de calcificación atendiendo a su a morfología. Estudios previos han documentado nódulos calcificados en pacientes con enfermedad arterial periférica; sin embargo, la presencia de distintos patrones morfológicos de calcificación sigue siendo desconocida. Paciente de 80 años derivado para angiografía coronaria por presentar disfunción sistólica. La coronariografía realizada mediante abordaje radial reveló la presencia de enfermedad calcificada grave de un vaso (porción media de la descendente anterior izquierda) así como calcificación mitral y aórtica. Los pullbacks de OCT realizados desde la arteria radial (6 ml de contraste a 3 mm por segundo, retirando 4 cm la vaina radial) revelaron la presencia de varias placas calcificadas (porción media de la arteria) definidas por la presencia de regiones heterogéneas, superficiales, bien definidas y con baja retrodispersión (vídeo 1 del material adicional). El corregistro angiografíco confirmó la presencia de una oclusión en la arteria ulnar.

Long-standing evidence supports the importance of maintaining healthy populations of microbiota for the survival, homeostasis, and complete development of marine mollusks. However, the long-term ecological effects of agricultural runoff on these populations remains largely unknown. Atrazine (6-Chloro-n-ethyl-n′-(1-methylethyl)-triazine-2,4-diamine), a prevalent herbicide in the United States, is often used along tributaries of the Chesapeake Bay where oyster breeding programs are concentrated. To investigate any potential effects atrazine maybe having on mollusk-prokaryote interactions, we used 16S rRNA gene amplicons to evaluate how microbial compositions shift in response to exposure of environmentally relevant concentrations of atrazine previously found within the Chesapeake Bay. The dominant bacterial genera found within all groups included those belonging to Pseudoalteromonas, Burkholderia, Bacteroides, Lactobacillis, Acetobacter, Allobaculum, Ruminococcus, and Nocardia. Our results support previously published findings of a possible core microbial community in Crassostrea virginica. We also report a novel finding: oysters exposed to atrazine concentrations as low as 3 µg/L saw a significant loss of a key mutualistic microbial species and a subsequent colonization of a pathogenic bacteria Nocardia. We conclude that exposure to atrazine in the Chesapeake Bay may be contributing to a significant shift in the microbiomes of juvenile oysters that reduces fitness and impedes natural and artificial repopulation of the oyster species within the Bay.

Massive coronary air embolism and intraprocedural stent thrombosis are a very infrequent but live-threatening complications of coronary interventions. The simultaneous occurrence of both have never been published yet. In this case report, 50-years-old male, with prior history of dyslipidemia is presented. Coronary air embolism is a rare complication of cardiac catheterization with a known incidence of 0.1% to 0.3% of all the procedures. This case exemplifies that the strategy of using directly a guiding catheter previous the contralateral diagnostic angiography if the EKG changes are manifest, is valid.

Resumen Introduccion y objetivos La correccion anatomica es el tratamiento de eleccion para neonatos con transposicion de grandes arterias. El objetivo es analizar resultados a medio plazo de esta intervencion. Metodos Estudio retrospectivo de los registros clinicos de todos los pacientes consecutivos operados mediante cirugia de intercambio arterial en el hospital infantil desde 1985 hasta 2010. Resultados Se intervino a 155 pacientes (el 68% varones) a una mediana de edad de 13 dias: el 64% con transposicion completa con septo integro; el 46% con comunicacion interventricular, y el 4,5% con enfermedad del arco aortico asociada. El patron coronario fue el usual en el 63%. Se realizo cirugia previa al 6,5%. De 137 supervivientes seguidos durante una mediana de 6 anos, la mortalidad tardia fue del 2,9%, el 50% debido a complicaciones coronarias. El 18% requirio reintervencion quirurgica y/o angioplastia: el 95,6% por estenosis en el tronco y/o las ramas pulmonares y el 4,3% por insuficiencia aortica. En la ultima revision estaban en clase funcional I (92%) y sin arritmias (95%). La fraccion de eyeccion del ventriculo izquierdo fue mayor del 55% en el 95%, el 28% tenia insuficiencia aortica (el 78% de grado I ) y el 31%, estenosis a la salida del ventriculo derecho (gradiente medio superior a 25 mmHg). Conclusiones Los pacientes con correccion anatomica presentan buena supervivencia y buen estado funcional a medio plazo; las lesiones residuales del tronco o la arteria pulmonar son la complicacion mas frecuente y causa de reintervencion. La muerte tardia de causa cardiaca no es un suceso frecuente, pero parece relacionado con complicaciones coronarias. Aunque hay casos de insuficiencia aortica precoz, aun desconocemos la evolucion a largo plazo en la vida adulta de la dilatacion de la neorraiz de aorta e insuficiencia aortica.

No hay resúmenes disponibles. ECA Estudios Centroamericanos, Vol. 61, No. 696, 2006: 1029-1032.

Introduction and objectives The arterial switch operation is currently the preferred surgical approach for complete transposition of the great arteries. We sought to determine the mid-term results of this intervention. Methods A single-institution retrospective review of clinical records of all consecutive patients who underwent the arterial switch surgery between 1985 and 2010. Results Overall, the operation was performed on 155 patients (68% boys) at a median age of 13 days: 64% with an intact septum, 46% with a ventricular septal defect, and 4.5% with associated aortic arch anomaly. The usual coronary pattern was found in 63%. Palliative surgery was performed prior to arterial switch in 6.5%. In all, 137 perioperative survivors were followed for a median of 6 years. Late mortality was 2.9%, of which 50% was due to coronary complications. Eighteen percent required surgical and/or percutaneous reintervention: 95.6% for right-sided obstruction and 4.3% for aortic regurgitation. At last follow-up, 92% had functional class I symptoms and 95% were free of arrhythmias. The left ventricular ejection fraction was greater than 55% in 95%, 28% had neoaortic regurgitation (78% mild regurgitation), and 31% had right ventricular outflow tract obstruction with a mean gradient according to echocardiography greater than 25 mmHg. Conclusions Mid-term survival of patients after arterial switch operation is excellent and their functional status is good. However, a few patients have residual lesions and a need for further intervention during follow-up, mostly for right-sided obstructions. Late mortality was uncommon and was related to coronary complications. Neoaortic root dilation and regurgitation are not major issues in early adulthood, but the long-term course of these lesions is still unknown.

This paper describes practices of the Supplementary Instruction (SI) Problem-Solving Workshop in helping entering engineering students develop the concept of problem solving and obtain the necessary knowledge and skills required to succeed in their courses.