Disfunción miocárdica y su utilidad pronóstica en sepsis y choque séptico / Myocardial dysfunction and its prognostic utility in sepsis and septic shock

Introducción: la sepsis es una disfunción orgánica poten- cialmente mortal que está asociada a una infección; tiene alta morbilidad y mortalidad. La disfunción miocárdica aso- ciada a sepsis es frecuente y se asocia con desenlaces desfavorables. Objetivo: describir la distribución de la disfunción miocárdica por ecocardiografía transtorácica y estimar su utilidad pronóstica en sepsis y choque séptico. Material y métodos: estudio de cohorte multicéntrico prospectivo, realizado en cuatro centros de referencia de Bucaramanga y su área metropolitana. Se incluyeron 271 pacientes con diagnóstico de sepsis y choque séptico, a quienes se les realizó ecocardiograma transtorácico y se les dio seguimiento por 30 días. Resultados: no hubo diferencias en la fracción de eyección del ventrículo izquierdo entre sobrevivientes a los 30 días y no sobrevivientes. Se registraron 51 pacientes (48.7%) con disfunción diastólica grado I, 14.5% con disfunción grado II y 36.75% con disfunción grado III. Los pacientes con disfunción diastólica grado I tuvieron una mortalidad más alta que aquellos con disfunción diastólica de grado II (p = 0.023). Conclusiones: la mayor mortalidad registrada en la disfunción diastólica grado I sugiere que los pacientes con bajas presiones de llenado tienen peores desenlaces. Por otra parte, la fracción de eyección del ventrículo izquierdo por sí sola no se relaciona con mayor mortalidad en sepsis.

Background: Sepsis is a potentially mortal infection which is related to multiple organ dysfunction; it has a high morbidity and mortality. Myocardial dysfunction is frequent in sepsis and it is related to unfavorable outcomes. Objective: To describe by transthoracic echocardiography the clinical distribution of myocardial dysfunction in sepsis and septic shock and estimate its prognostic utility. Material and methods: Cross-sectional study based on a multi-centric prospective cohort study in 4 reference centers in Bucaramanga, Colombia, and its metropolitan area. 271 patients with sepsis and septic shock were included; they underwent standard transthoracic echocardiography and a 30-day follow-up. Results: There was no difference in the left ventricular ejection fraction (p = 0.061) between survivors and non-survivors. 51 patients (48.71%) had grade I diastolic dys-function, 48 patients (14.52%) had grade II dysfunction and 21 patients (36.75%) had grade III diastolic dysfunction. Mortality was higher in patients with grade I diastolic dysfunction when compared to those with grade II dysfunction (p = 0.023). Conclusions: The higher mortality in grade I diastolic dysfunction suggests that patients with low filling pressures have worst outcomes. On the other hand, left ventricular ejection fraction per se is not associated with a higher mortality in sepsis.

Manejo perioperatorio de paciente con COVID-19 / Perioperative management of the patient with COVID-19

Resumen: En la actualidad, la pandemia de SARS-CoV-2 ha puesto a prueba los sistemas de salud en toda su extensión a lo largo del mundo. Se desconoce el impacto del estrés quirúrgico y de la anestesia sobre la predisposición a una nueva infección por COVID-19, o la exacerbación de la infección en un paciente infectado por este virus que se va a operar. Aunque la mortalidad de COVID-19 está entre 1-5%, la mayoría de las muertes han ocurrido en pacientes de edad avanzada con afecciones cardiopulmonares subyacentes, la mayoría de ellos hipertensos, diabéticos y con obesidad, por lo cual, se debe poner especial atención en su manejo. La preparación y planeación perioperatoria cuidadosa es clave para lograr con éxito una adecuada atención clínica y mantener la seguridad del equipo de salud en un momento difícil y de alto riesgo. Un papel adicional del anestesiólogo, considerando que es el médico con mayor experiencia en el manejo de la vía aérea, consiste en apoyar a los servicios de emergencia para la intubación endotraqueal de los pacientes que requieren apoyo ventilatorio, siendo un procedimiento con recomendaciones de protección muy específicas. Por lo tanto, existe un compromiso como especialistas de conocer el tema a fondo y protegernos, así como al equipo de profesionales de la salud que se exponen salvando vidas durante esta contingencia.

Abstract: Currently, the SARS-CoV-2 pandemic has put health systems to the test throughout their world. The impact of surgical stress and anesthesia on predisposition to a new COVID-19 infection or exacerbation of the infection in a COVID-19 infected patient to be operated on is unknown. Although COVID-19 mortality is between 1-5%, most deaths have occurred in elderly patients with underlying cardiopulmonary conditions, most of them hypertensive, diabetic and obese, therefore, it should be specially attention in its handling. Carefull perioperative preparation and planning is key in successfully achieving adequate clinical care and maintaining the safety of the health team in a difficult and high risk moment. An additional role for the anesthesiologist, considering that he has the most experience in the management of the airway, is to support the emergency services for endotracheal intubation of patients who require ventilatory support, being a procedure with very specific protection recommendations. Therefore, there is a commitment as specialists, to know the subject thoroughly and protect ourselves along with the health team involved in saving lives during this contingency.

Uso de coadyuvantes en dolor postoperatorio / Use of adjuvants in postoperative pain

Resumen: Los analgésicos coadyuvantes son compuestos que tienen una baja potencia analgésica. Sin embargo, la sinergia con opioides incrementa su efecto y favorece una reducción en los eventos adversos de los narcóticos para el control del dolor postoperatorio. Las estrategias ahorradoras de opioides están relacionadas con el efecto de una variedad de receptores, de los cuales podemos nombrar: los antagonistas NMDA como la ketamina, magnesio y dextrometorfano, los agonistas α-2 como la clonidina y la dexmedetomidina, los inhibidores de la subunidad α-2δ de los canales de calcio como la pregabalina y la gabapentina, los bloqueadores de los canales de sodio como la lidocaína y, finalmente, los glucocorticoides. En esta revisión se describirán las características, indicaciones, dosis y niveles de evidencia del uso de los coadyuvantes de uso intravenoso y regional en el contexto perioperatorio. (visite http://www.painoutmexico.com para ver artículo completo y Tablas).

Abstract: The adjuvant analgesics are compounds that have a low analgesic potency. However, with these compounds, the adverse effects of opioids may be diminished for the control of postoperative pain. Opioid-sparing strategies are related to the effect on a variety of receptors, of which we should name: the NMDA antagonists such as ketamine, magnesium and dextromethorphan, the α-2 agonists such as clonidine and dexmedetomidine, subunit α-2δ of calcium channels inhibitors; such as pregabalin and gabapentin, sodium channels blockers such as lidocaine and finally glucocorticoids. In this review we describe the characteristics, indications, doses and levels of evidence of use of adjuvants in the perioperative context (visit http://www.painoutmexico.com to see the full article and Tables).

Modulações dos efeitos Simon e Stroop espacial por tarefas prévias de compatibilidade espacial / Modulations of Simon and spatial Stroop effects due to previous spatial compatibility tasks / Modulaciones de los efectos Simon e Stroop espacial por tareas anteriores de compatibilidad espacial

A localização espacial é uma característica intrínseca do estímulo que não pode ser ignorada e afeta a seleção da resposta correta em várias tarefas. Este efeito, denominado Compatibilidade Estímulo-Resposta, está presente nas tarefas de Compatibilidade espacial, Simon e Stroop espacial. O efeito Simon é modulado se, antes de executar a tarefa, os participantes executam uma tarefa incompatível de compatibilidade espacial. Essa modulação, chamada de transferência de aprendizagem é atribuída a dissociações entre memórias de longo e curto prazo. Não foi ainda estudado se esta prática incompatível modula o efeito Stroop espacial. Neste trabalho, testamos 32 participantes empregando um desenho experimental que permite estudar e separar os efeitos Simon e Stroop espacial na mesma tarefa e testar a hipótese de uma transferência generalizada do aprendizado por uma prática incompatível. Os resultados indicaram que a tarefa prévia incompatível modula apenas o efeito Simon, contrariando a hipótese da transferência generalizada do aprendizado.

Spatial location is an intrinsic characteristic of the stimulus that influences the execution of the correct response in various tasks. The effect is named Stimulus-Response Compatibility, with the Spatial Compatibility, Simon, and Spatial Stroop tasks being examples of this phenomenon. The Simon effect is modulated if participants perform a previous incompatible spatial compatibility task. This modulation, called transfer-of-learning effect, has been attributed to dissociations between long-term memory and short-term memory. It had not yet studied whether this incompatible practice modulates the spatial Stroop effect. In this work, we tested 32 volunteers in an experimental design that allows us to study and separate the Simon and spatial Stroop effects in the same task and test the hypothesis of a generalized transfer-of-learning effect by an incompatible practice. The results indicate that a previous incompatible task modulates only the Simon effect, contradicting the hypothesis of the generalized transfer of learning after an incompatible practice.

La localización espacial es una característica intrínseca del estímulo que afecta la selección de la respuesta en diversas tareas. Este efecto, denominado la compatibilidad estímulo-respuesta, es presente en la tarea compatibilidad espacial, Simon y Stroop espacial. El efecto Simon es modulado si los participantes realizan previamente una tarea incompatible de compatibilidad espacial. Esta modulación, llamada efecto de transferencia de aprendizaje, se ha atribuido a las disociaciones entre memoria a largo e corto plazo. Todavía no se ha estudiado si esta práctica incompatible modula el efecto Stroop Espacial. En este trabajo, probamos 32 estudiantes en un diseño experimental que nos permite estudiar y separar los efectos de Simon y Stroop espacial en la misma tarea y probar la hipótesis de un efecto generalizado de transferencia de aprendizaje por una práctica incompatible. Los resultados indican que la tarea incompatible anterior modula sólo el efecto Simón, contrariamente a la hipótesis de la transferencia generalizada de aprendizaje.

Valores hematológicos e bioquímicos de pinguins-de-Magalhães em reabilitação no Espírito Santo, sudeste do Brasil / Hematological and biochemical values of Magellanic penguins in rehabilitation in Espírito Santo, southeastern Brazil

Este trabalho apresenta valores hematológicos e bioquímicos de pinguins-de-Magalhães (Spheniscus magellanicus) juvenis que arribaram no Espírito Santo e Rio de Janeiro, litoral sudeste do Brasil, e foram encaminhados a reabilitação. Os valores médios obtidos foram: eritrócitos 2.55±0.54 milhões/µL; hemoglobina 13,37±3,91g/dL; hematócrito 41,5±0,04%; proteína plasmática 6,34±0,81g/dL; leucócitos 16.301±6.402/µL; trombócitos 20.516±4.591 células/µL; volume corpuscular médio (VCM) 172,0±53,0 fL; concentração de hemoglobina corpuscular média (CHCM) 26,41±0,02%; alanina transaminase (ALT) 50,0±17,89 U/L; ácido úrico 8,93±3,0mg/dL; albumina 1,68±0,53g/dL; cálcio 9,7±0,57mg/dL; fósforo 10,39±8,5mg/dL e glicose 211,6±30,3mg/dL. Valores de eritrócitos, VCM e CHCM foram discrepantes em relação aos valores de referência atuais. Valores de leucócitos e trombócitos tem significado inconclusivo. Hematócrito, hemoglobina, proteína plasmática e valores bioquímicos forneceram importante contribuição para o estabelecimento de parâmetros de referência.(AU)

This paper reports hematological and biochemical values of juveniles Magellanic penguins (Spheniscus magellanicus) stranded in Espírito Santo and Rio de Janeiro, Southeastern Brazil, that were sent for rehabilitation. The average values were: erythrocytes 2.55±0,54 milhões/µL, hemoglobin 13.37±3,91g/dL, hematocrit 41.5±0.04%, plasma protein 6.34±0.81g/dL, leukocytes 16,301±6,402/µL, thrombocytes 20,516±4,591 células/µL3, mean cell volume (MCV) 172.0±53.0 fL, mean cell hemoglobin concentration (MCHC) 26.41±0.02%, alanine transaminase (ALT) 50.0±17.89 U/L, uric acid 8.93±3.0mg/dL, albumin 1.68±0.53mg/dL, calcium 9.7±0.57mg/dL, phosphorus 10.39±8.5mg/dL and glucose 211.6±30.3mg/dL. Values of erythrocytes, MCV and MCH were discrepant in relation to the current reference values. Leukocytes and thrombocytes values has meant inconclusive. Hematocrit, hemoglobin, plasma protein and biochemical values provided important contribution for the establishment of reference parameters.(AU)

Alteraciones cardíacas en el Síndrome de Down. Unidad de Genética Médica, Universidad de Los Andes, Mérida- Venezuela

El síndrome de Down es una entidad clínica-genética que se asocia frecuentemente con cardiopatías congénitas entre 40-60% y corresponde un aspecto importante en su evolución. Objetivo: Describir los diferentes tipos de alteraciones cardiacas presentes en los pacientes con síndrome de Down, evaluados en la Unidad de Genética Médica de la Universidad de Los Andes y compararla con estudios similares. Pacientes y métodos: Se realizó un estudio observacional y descriptivo desde enero de 2009 a diciembre de 2012 en 100 pacientes con síndrome de Down con estudio citogenético y de ecocardiografía. Resultados: Las cardiopatías congénitas se presentaron en 63% de los pacientes. La comunicación interventricular fue la lesión simple aislada más frecuente con 14 casos y la alteración cardiaca compleja aislada más frecuente fue el canal auriculoventricular completo en cuatro casos. Conclusiones: Las malformaciones cardíacas congénitas se presentan en una frecuencia importante en la población con síndrome de Down, los diversos tipos varían en diferentes etnias y en períodos diferentes en el mismo país. Se debe enfatizar la realización del diagnóstico precoz para evitar las complicaciones que se pueden exhibir de forma más rápida y graves en los individuos con esta entidad genética.

Down syndrome is a clinical-genetic entity that is often associated with congenital heart disease between 40-60% and has an important aspect in its evolution. Objective: Describe the different types of cardiac alterations present in patients with Down syndrome, evaluated at the Medical Genetics Unit of the University of Los Andes and compared with similar studies. Patients and methods: A descriptive and observational study was conducted from January 2009 to December 2012 with 100 patients with Down syndrome with cytogenetics study and echocardiography. Results: Congenital heart disease occurred in 63% of patients. The ventricular septal defect was the most frequent isolated single lesion with 14 cases and the complex cardiac dysfunction was the most frequent isolated complete atrioventricular canal in four cases. Conclusions: Congenital heart defects are present in a significant frequency in the population with Down syndrome, various types vary in different ethnic groups and in di erent periods in the same country. It should be emphasized the realization of early diagnosis to prevent complications that can be displayed in a more rapid and severe in individuals with this genetic entity.

Pesquería y biología de Rhinobatos percellens (Rajiformes: Rhinobatidae) capturados por la pesquería artesanal de playa La Pared, Venezuela / Fishery and biology of Rhinobatos percellens (Rajiformes: Rhinobatidae) caught by the artisanal fishery at La Pared beach, Venezuela

R. percellens is incidentally caught in Venezuela by the artisanal fishery using bottom gillnets. This species was classified by the IUCN as being near threatened, and there is poor knowledge about its biology and fishery in Venezuela. For this reason, we analyzed the specimens caught by the artisanal fleet in playa La Pared, once a week, from January to December 2007. We determined total length, sex and maturity for each captured specimen. A total of 210 specimens were analyzed, 159 females and 51 males. The 81% of all specimens caught were adults, but within this group 27% were pregnant. The average size of sexual maturity was found between 51 and 52cm for females and males, respectively. Adult females were found all year round, and pregnant females in seven of the months sampled; highest numbers were found between February-March and September. The analyzed females had a total of 96 embryos with a size range between 2 and 19cm, with a maximum fertility of four embryos per litter. February and June-July showed the maximum breeding time, and considering the broad range of embryos sizes and the frequency of pregnant females along the different months, allow us to believe that they reproduce throughout the year. Fishing regulation including minimum catch size in relation to maturity length and release of pregnant females in water is recommended.

Rhinobatos percellens es capturada en Venezuela por la flota artesanal que opera con redes de fondo. Está clasificada por la IUCN como casi amenazada, y no existen estudios sobre su biología o pesquería en el país. Por ello, se analizaron desembarques de la pesca artesanal de playa la Pared (isla de Margarita) durante enero-diciembre 2007. A cada ejemplar capturado se le determinó la longitud total, sexo y madurez. Fueron analizados 210 ejemplares, 159 hembras y 51 machos. El 81% de los ejemplares se encontraban maduros y un 27% de este grupo correspondió a hembras grávidas. La talla media de madurez sexual quedó ubicada en 51 y 52cm para hembras y machos, respectivamente. Se detectaron hembras maduras todo el año, y hembras grávidas en siete meses. Fueron analizados 96 embriones con tallas entre 2-19cm, siendo la fecundidad máxima cuatro embriones. La variación de las longitudes de los embriones entre los meses del año indican dos picos máximos de alumbramiento al año pero no existe una sincronía en la cópula ya que la especie se reproduce prácticamente todo el año. Se recomienda elaborar regulaciones pesqueras que incluyan una talla mínima de captura en función de la talla de madurez señalada y liberar las hembras grávidas al agua.

Distribución, densidad y estructura de talla de Oreaster reticulatus y Luidia senegalensis (Echinodermata: Asteroidea) en isla de Cubagua, Venezuela / Distribution, density an size structure of Oreaster reticulatus and Luidia senegalensis (Echinodermata: Asteroidea) in Cubagua Island, Venezuela

There is limited biological information about the starfish Oreaster reticulatus and the nine-armed starfish Luidia senegalensis in Venezuelan waters. These species are currently considered threatened in many localities of the Caribbean, Brazil and Colombia. Therefore, the aim of this study was to describe their population density, size distribution and population structure in Cubagua Island. During 2008, 52 stations located around the island were evaluated using band transects of 50m2. Each organism was counted and measured (maximum radius), and its size was compared to the maturity length reported in the literature. The results for O. reticulatus include: 167.3ind./ha; 33% juveniles and 67% adults; average size of 10.7±5cm (range: 2.2-21cm); a wide distribution around the island, with higher densities in the Eastern and Southwest areas. The 50% of the specimens were found in seagrass beds, 25% in sand, 16% in areas covered by decomposed seaweeds, 9% in oyster beds and 1% coralline patches. The densities of O. reticulatus were higher than those reported in the Caribbean, Panama and Puerto Rico, but lower than Venezuelan National Parks: Mochima and Morrocoy; as well as in the Virgin Islands and Belize. For L. senegalensis we found an average density of 40ind./ha; 95% exceeded the reported size at maturity, with mean length of 12cm±3.5cm (range: 3.5-22.3cm); they were found only in 15% of the stations of which 92.5% were sandy bottoms and the other 7.5% oyster beds. The degree of aggregation of L. senegalensis was greater than O. reticulatus, with an estimated k of 0.06. However, it was not possible to compare the densities of L. senegalensis with any other study. For both species is recommended to carry out reproductive studies and to monitor their population densities to infer temporal variations.

Las estrellas de mar: Oreaster reticulatus y Luidia senegalensis, han sido objeto de escasos estudios en aguas venezolanas. Actualmente son consideradas especies amenazadas en diversas zonas del Caribe, Brasil y Colombia. Por esto, se planteó como objetivo generar información sobre su densidad poblacional, distribución y estructura de talla en los alrededores de la isla de Cubagua. Para ello, durante el año 2008, se realizaron cuatro transectas bandas de 50m2 cada una, en 52 estaciones ubicadas alrededor de la isla. Entre los resultados obtenidos para O. reticulatus destacan: 167.3ind/ha, un 33% inmaduros y 67% adultos con un promedio de tallas de 10.7±5cm (rango: 2.2-21cm); una amplia distribución en los alrededores de la isla, con mayores densidades en la zona este y suroeste. Luidia senegalensis mostró una densidad promedio de 40ind/ha, 95% superaba la talla de madurez reportada, con talla promedio de 12cm±3.5cm (rango: 3.5-22.3cm). Se recomienda realizar estudios de reproducción, así como monitoreos de sus densidades poblacionales que permitan inferir sus variaciones temporales.

Antígenos de Plasmodium falciparum, blancos de la respuesta inmunitaria humoral en pacientes tratados con cloroquina / Antigens of Plasmodium falciparum, target of humoral immune response in patients treated with chloroquine

Se planteó identificar antígenos que pudieran ser reconocidos por los anticuerpos IgG1 e IgG3, descritos como protectores en la infección malárica, en personas con respuesta clínica adecuada (RCA) o falla al tratamiento (FT) antimalárico, provenientes de localidades con diferentes grados de endemicidad. Se evaluaron por Immunoblotting muestras de sueros de individuos provenientes de tres localidades del Edo. Amazonas (Venezuela): Puerto Ayacucho (Atures), San Juan de Manapiare (Manapiare) y Platanal (Alto Orinoco). La reactividad de IgG, IgG1 e IgG3 frente a componentes antigénicos del extracto de P. falciparum (FCB2), permitió identificar un mayor número de moléculas específicas en los pacientes con RCA que en los pacientes con FT. La frecuencia de reconocimiento de polipéptidos fue baja en las tres localidades, algunas moléculas con una frecuencia de reconocimiento igual o mayor al 20% pertenecían a sueros de individuos de las localidades de Puerto Ayacucho y Platanal, ambas con exposición permanente a P. falciparum. Dado el reconocimiento de polipéptidos por IgG, IgG1 e IgG3 en sueros de pacientes con RCA, estos podrían ser considerados como posibles blancos relevantes de la respuesta inmunológica protectora que coadyuven con el tratamiento antimalárico. Esto contribuiría al desarrollo y diseño de vacunas más efectivas, que prevengan la infección malárica y/o potencien la eficacia a la quimioterapia.

Here we studied the presence of antigens recognized by IgG1 and IgG3 antibodies, thought as protective, in patients with adequate clinical response (RCA) or treatment failure (FT), living in areas of different degrees of endemicity. Immunoblotting was evaluated from serum samples of individuals from three locations in the State Amazonas (Venezuela): Puerto Ayacucho (Atures), San Juan de Manapiare (Manapiare) and Pantanal (Alto Orinoco). The reactivity of IgG, IgG1 and IgG3 against antigenic components of the extract of P. falciparum (FCB2) identified a greater number of specific molecules in patients with RCA in patients with AFT. The frequency of recognition of polypeptides was low in all three locations, with some molecules having a recognition rate of greater than or equal to 20% sera of individuals belonging to the towns of Puerto Ayacucho and Platanal, both with cases of P. falciparum. Given the recognition of polypeptides by IgG, IgG1 and IgG3 in sera of patients with RCA, they could be considered as possible targets for relevant protective immune responses that contribute to malaria treatment. This would contribute to the development and design of more effective vaccines that prevent malaria infection and/or enhance the efficacy of chemotherapy.

Quinolizidine alkaloid composition in different organs of Lupinus aschenbornii

Lupinus aschenbornii S. Schauer, Fabaceae, grows in the Central Highlands of Mexico, at altitudes between 2800 to 4300 m above sea level. The alkaloid patterns in organs of L. aschenbornii were analyzed by Gas-Liquid Chromatography-Mass Spectrometry (GLC-MS). Quinolizidine alkaloids (QA) were identified according to their mass fragmentation patterns, in combination with their Kovats retention indeces. Total QA content in organs differed substantially: seed contained 3.3 mg/g dry weight, flowers 2.8 mg/g DW, leaves 1.9 mg/g DW, stems 1.5 mg/g DW, and pods 1.4 mg/g DW. Roots do not accumulate QA and their profiles differed considerably: while seed stored N-formylangustifoline (17 percent), 17-oxolupanine (16 percent), multiflorine (11 percent) and an unidentified alkaloid (n.i.) 2869 (11 percent) as main QA, sparteine was absent. In flowers, sparteine reached 73 percent, in leaves up to 80 percent, in stems up to 32 percent and in pods up to 96 percent. Other QA present were lupanine (32 percent in stem, 9 percent in flower and 7 percent in seed); N-formylangustifoline (9 percent in stem and 4 percent in flower); multiflorine (6 percent in stem and 3 percent in flower). Differences in QA profile might be a strategy of lupins to avoid adaptation of possible predators because the different QA have different pharmacological properties.

SÍNTESIS DE CATALIZADORES DE Ni/ZnO/Al2O3 PARA LA REACCIÓN WGS A TRAVÉS DEL ESTUDIO DE LAS PROPIEDADES ESTRUCTURALES Y CATALÍTICAS DE Ni/ZnO Y M/Al2O3 / NTHESIS OF Ni/ZnO/Al2O3CATALYSTS FOR THE WGS REACTION FROM THE STUDY OF STRUCTURAL AND CATALYTIC PROPERTIES OF Ni/ZnO AND NÍ/AI2O3 / SÍNTESE DE CATALISADORES DE Ni/ZnO/Al2O3PARA A REAÇÃO WGS MEDIANTE O ESTUDO DAS PROPRIEDADES ESTRUTURAIS E CATALÍTICAS DE Ni/ZnO E M/Al2O3

El uso del hidrógeno para la generación de energía ha renovado el interés por la reacción WGS. Los catalizadores usados para acelerar esta reacción requieren condiciones especiales de reducción, lo que dificulta su aplicación en celdas combustibles para la producción de energía. En este trabajo se sintetizaron catalizadores de níquel soportado en óxido de cinc o aluminio usando un diseño factorial 3² en el caso de los materiales con cinc. Los resultados obtenidos se emplearon en la síntesis de sólidos trimetálicos de níquel, cinc y aluminio en las condiciones más propicias para garantizar mejor actividad y selectividad. Los sólidos fueron caracterizados por EDX, DRX, TPR y evaluados en la reacción WGS a 260 °C. Se observó la incorporación de los cationes Zn²+ yAl³+ en la red del NiO, lo que disminuye su reducibilidad con hidrógeno. Los materiales que contenían cinc fueron 100% selectivos para la reacción WGS. En la evaluación de los catalizadores con níquel y aluminio hubo formación de metano; sin embargo, este compuesto no fue observado durante la evaluación catalítica de los sólidos trimetálicos. Los catalizadores más activos fueron aquellos calcinados en temperaturas más bajas y con las menores cantidades de cinc.

The use of hydrogen for power generation has again awaken the interest in the WGS reaction. The catalysts used to accelerate this reaction need special conditions of reduction. This limits their application in fuel cells for energy production. In this work, nickel catalysts-supported in zinc oxide or aluminum oxide were synthesized by using a 3² factorial design with materials containing zinc. The results were used for the synthesis of trimetallic solid containing nickel, zinc and aluminum, in the most favorable conditions to ensure high activity and selectivity. The solids were characterized by EDX, XRD, TPR and evaluated in the WGS reaction at 260 °C. The incorporation of Zn2+ and Al3+ cations was observed in the lattice of NiO. This phenomenon affects the reducibility of these materials with hydrogen. The materials containing zinc were of 100 per cent selectivity for the reaction under study. In the case of nickel and aluminum catalysts, methane formation was observed, but this species was not detected in the trimetallic catalysts. The catalytic activity of trimetallic materials is consistent with the trends in bimetallic nickel-zinc or nickel-aluminum materials. The most active catalysts were those calcined at the lowest temperatures with the smallest amounts of zinc.

O uso do hidrogênio para a geração de energia tem renovado o interesse pela reação WGS. Os catalisadores usados para acelerar esta reação requerem condições especiais de redução. Isso dificulta a sua aplicação em células combustíveis para a geração de energia. Neste trabalho se sintetizaram catalisadores baseados em níquel suportado em oxido de zinco ou alumínio, usando um desenho fatorial 3² no caso dos materiais contendo zinco. Os resultados obtidos foram usados para a síntese de sólidos tri-metálicos contendo níquel, zinco e alumínio nas condições ótimas para aumentar a atividade e seletividade dos materiais. Os sólidos foram caracterizados pelas técnicas EDX, DRX, TPR e avaliados na reação WGS a 260 °C. Observou-se a incorporação dos cátions Zn2+ eAl3+ na rede do NiO, o que diminui a redução dos sólidos com hidrogênio. Os sólidos contendo zinco foram 100% seletivos para a reação em estudo. Na avaliação dos catalisadores contendo níquel e alumínio ocorreu a formação de metano, no entanto esta espécie não foi observada na avaliação catalítica dos sólidos tri-metálicos. Os catalisadores mais ativos foram os calcinados nas temperaturas mais baixas e com menores quantidades de zinco.

Distribución y densidad de dos especies de holoturoideos en la isla de Cubagua, Venezuela

Distribution and density of two holothurian species in Cubagua Island, Venezuela. Holothurian populations in the Caribbean have been significantly depleted in some areas, and others are still in danger to satisfy international markets. In Venezuela, this marine resource has been illegally exploited since the early 1990s. To contribute with their management and protection, this work analyzed the distribution, abundance and population structure of two commercial holothurians Isostichopus badionotus and Holothuria mexicana in Cubagua Island shores. A total of 52 stations were studied around the island during the year 2008. Surveys included visits to each station, for which a band transect of 50m² with four replicates were carried out. The results show that I. badionotus has a higher distribution on the East coast of the island, and is found over Thalassia testudinum beds or bivalve molluscs aggregations, with an average density of 0.011ind/m², C.I. 95%=0.005-0.017, n=122, and a general abundance estimated in 117ind/ha. H. mexicana has been practically depleted (0.001 ind/m2 C.I. 95%=0.0002-0.0013, 7.7 ind/ha, n=8). We recommend the maintenance of the total ban adopted in 1997 to assure the protection of these species, mainly because no previous data supported the start of the fishery, and also, because the current densities are still very low when compared to other areas in Venezuela and the Caribbean. These are animals easy to catch, susceptible to overfishing, and with a very low recovery rate; thus, more control is required from the local authorities. Rev. Biol. Trop. 59 (2): 843-852. Epub 2011 June 01.

En algunas zonas del Caribe, poblaciones enteras de holoturias han sido agotadas. En Venezuela, éste recurso ha sido explotado ilegalmente desde inicios de 1990. Por esta razón, se planteó estimar la distribución, abundancia y estructura poblacional de las holoturias comerciales Isostichopus badionotus y Holothuria mexicana en la isla Cubagua. Para ello, durante el año 2008, se realizaron cuatro transectas bandas de 50m² cada una en 52 estaciones ubicadas alrededor de la isla. Entre los resultados obtenidos destacan: I. badionotus presenta mayor distribución en el lado este de la isla, sobre fondos de Thalassia testudinum o bancos de moluscos bivalvos; con una densidad promedio de 0.011±0.022ind/m² (n=122), y una abundancia general estimada en 117ind/ha. Se identificaron cinco posibles zonas de crianza para esta última especie. H. mexicana ha sido prácticamente agotada (0.001±0.002ind/m², 7.7ind/ ha, n=8). Se recomienda mantener la veda total implantada en 1997, principalmente por no tener conocimiento de las densidades previas al inicio de la pesquería; por considerar que la densidad actual sigue siendo muy baja en comparación con otras zonas de Venezuela, y por ser animales de fácil captura, rápidamente sobreexplotables y de recuperación lenta.

Left-right judgment of haptic stimuli representing the human hand

The handedness recognition of visually perceived body parts engages motor representations that are constrained by the same biomechanical factors that limit the execution of real movements. In the present study, we used small plastic cutouts that represented the human hand to investigate the properties of mental images generated during their haptic exploration. Our working hypothesis was that any handedness recognition task that involves body parts depends on motor imagery. Forty-four blindfolded, right-handed volunteers participated in a handedness evaluation experiment using their index finger to explore either the back or palm view of a haptic stimulus that represented the human hand. The stimuli were presented in four different orientations, and we measured the subjects' response times. Our results showed that stimulus configurations that resemble awkward positions of the human hand are associated with longer response times (p < .006), indicating that the haptic exploration of stimuli that represent body parts also leads to motor imagery that is constrained by biomechanical factors

Development of IgY antibodies in chickens and IgG in rabbits immunized against proteins of Pythium insidiosum isolated from horses in the state of Rio de Janeiro / Desenvolvimento de Anticorpos IgY em galinhas e IgG em coelhos imunizados contra proteínas de Pythium insidiosum isolado de equinos no Estado do Rio de Janeiro, Brasil

Pythiosis is caused by Pythium insidiosum and the occurrence of disease in horses was described in the North and Northwest State of Rio de Janeiro, Brazil. The disease was described in cattle, sheep, humans, and horses in different states and regions across the country. This paper describes the development of IgY and IgG polyclonal antibodies, in chicken and rabbits, respectively against proteins extracted from kunkers and hyphae of P. insidiosum from affected horses. The proteins were recognized by chicken, rabbit and horse antibodies by immunodiffusion and Western blot against majority bands of 27 and 43 KDa, and titrated by ELISA. The antibodies IgY developed by the first time against Brazilian strains of P. insidiosum may represent a valuable tool in the detection of antigens of the pathogen and contribute to further studies aimed at immunotherapy and knowledge about this disease in endemic areas in Rio de Janeiro and in Brazil.

Pitiose é causada por Pythium insidiosum e a doença foi descrita em equinos no Norte e Noroeste do Estado do Rio de Janeiro, Brasil. A doença foi descrita em bovinos, ovelhas, humanos e cavalos em diferentes estados e regiões do país. Este trabalho descreve o desenvolvimento de anticorpos policlonais, IgY e IgG, em galinha e coelho, respectivamente, contra proteínas extraídas de kunkers e hifas de P. insidiosum de cavalos doentes. As proteínas foram reconhecidas por anticorpos de galinha, coelho e cavalos contra as bandas majoritárias de 27 e 34 KDa em imunodifusão e Western blot tituladas por ELISA. Os anticorpos IgY desenvolvidos pela primeira vez contra cepas brasileiras de P. insidiosum podem representar um valioso instrumento na detecção de antígenos de patógenos e contribuem para novos estudos baseados na imunoterapia e no entendimento sobre esta doença em áreas endêmicas no Rio de Janeiro e em todo o país.

Deficiência visual e plasticidade no cérebro humano / Visual impairment and cerebral plasticity in the human brain / Deficiencia visual y plasticidad cerebral

O ser humano é capaz de analisar o mundo à sua volta por meio de informações provenientes das diversas modalidades sensoriais. A percepção do mundo a cada momento envolve a integração dessas informações em áreas multissensoriais existentes no cérebro humano. Dessa forma, podem-se imaginar as profundas transformações que ocorrem no cérebro após a perda de uma aferência sensorial. Estudos anatômicos, fisiológicos e comportamentais em animais têm sugerido que mudanças plásticas compensatórias devem também ocorrer nos seres humanos, alterando as conexões do córtex visual com os córtices somestésico e auditivo. Utilizando as novas idéias sobre as áreas multimodais e metamodais, pretendemos analisar como ocorre a reorganização dos sentidos remanescentes após a perda da visão.

Humans are able to analyze the world through information derived from various sensory modalities. After the loss of a given sense, anatomical, physiological and behavioral studies have shown that compensatory plastic changes take place in the cortex, first through the unmasking of synaptic contributions from other modalities, even in primary sensory areas. This fact underscores the metamodal theory of sensory cortical function and can be used to devise effective strategies to train the blind to compensate their loss through better use of the remaining sensory modalities.

El ser humano es capaz de analizar el mundo que lo rodea a través de información de las diversas modalidades sensoriales. La percepción del mundo en cada momento implica la integración de información multisensorial en las áreas existentes en el cerebro humano. Así, uno puede imaginar los profundos cambios que ocurren en el cerebro después de la pérdida de un aferente sensorial. Los cambios anatómicos, fisiológicos y de comportamiento en animales han sugerido que los cambios compensatorios plásticos también debem ocurrir en los seres humanos, cambiando las conexiones de la corteza visual con las cortezas auditivas y somestésicas. Con nuevas ideas sobre las áreas multimodal y metamod, analizamos la reorganización de los sentidos restantes después de la pérdida de la visión.

Identificação de marcadores moleculares em câncer de mama através da técnica de microarray utilizando uma plataforma de exons tumor-associados / Identification of breast cancer molecular markers through microarray technology using a tumor-associated exons platform

Análises recentes têm mostrado a ocorrência de splicing alternativo (AS) do mRNA em pelo menos 60% dos genes humanos, sendo que 80% desses eventos ocorrem dentro da região codificadora, aumentando a diversidade proteômica. ... Para identificar variantes de splicing diferencialmente reguladas em câncer de mama, 270 exons expressos em tecidos ... Esses exons foram imobilizados em membranas de nylon juntamente com controles positivos e negativos, e hibridizados contra amostras tumorais e normais de mama. ... Para validação técnica dos exons selecionados como superexpressos de acordo com os critérios estabelecidos, foi empregada a técnica de RT-PCR quantitativo (qRT-PCR), usando o mesmo grupo de amostras já utilizadas anteriormente. ... Os resultados mostraram que a razão do nível de expressão entre as 3 VCE e a expressão constitutiva do gene (VCE/EC) foi significativamente maior em amostras tumorais de mama quando comparadas às amostras normais (p<0,05), sugerindo que TRIM37-VCE, MK-STYX-VCE e BRRN1-VCE são, de fato, variantes de splicing superexpressas em câncer de mama. Essas variantes foram também avaliadas em um grupo independente de 40 amostras tumorais de mama para validar biologicamente a superexpressão da VCE em amostras tumorais de mama quando comparadas às amostras normais. Todos os dados foram correlacionados com características clínicas e histopatológicas das amostras.

Current analyses have shown that alternative mRNA splicing (AS) appears in at least 60% of human genes and 80% of these events occurs within the coding region, increasing the proteomic diversity. Some AS variants have been preferentially expressed in human tumors and are potential molecular markers, contributing to the development of more accurate diagnostic and prognostic factors as well as therapeutic targets. To identify differentially regulated splicing variants in breast cancer, 270 exons expressed in tumor tissues were selected by a computational analysis, of which 75 were associated with breast, because they are found to be expressed in libraries that originated from breast tumors and they were not found in the corresponding normal libraries. These exons were immobilized on nylon membranes together with positive and negative controls, and hybridized against tumor and normal breast samples. To identify the most highly expressed exons in tumor tissues, 3 comparisons were performed: 4 tumor against 2 normal breast cell lines (LTxLN), 27 tumor against 5 non-neoplasic breast tissues (TxN) and 4 matched tumor-normal samples (PTxPN). A Tstudent test was used to select for differentially expressed exons (p<0.05) in each comparison (LTxLN; TxN; PTxPN). Here, 24 were selected as over expressed exons in the LTxLN comparison, 79 exons in the TxN comparison and 195 exons in the PTxPN comparison. For technical validation, those exons having a fold change of ≥ 3 in tumor samples and being present in at least 2 comparisons were selected. Fourteen exons were identified by microarray experiments and evaluated through quantitative RT-PCR (qRTPCR), using the same sample set utilized previously. In order to test whether the exons selected by microarray experiments belonged to a prone over expressed splicing variant, 2 criteria were adopted: (1) Validation by qRTPCR of the variant that comprises the selected over expressed exon (VCE) (fold change ≥ 3); (2) For those exons confirmed in criterion (1), evaluation of whole gene expression (through the analysis of constitutive gene expression) is adopted as a secondary criterium. Three of the VCE's were confirmed through qRT-PCR as being over expressed in breast tumor, such as TRIM37-VCE, MK-STYX-VCE and BRRN1-VCE. The constitutive expression of the gene (EC) was analyzed by qRT-PCR, through the primer design within constitutive exons, that is, present in all variants of the gene. The results showed that the expression level ratio between the 3 VCE's and the constitutive expression of genes (VCE/EC) was significantly higher in tumor samples when compared to normal samples (p<0.05), suggesting that TRIM37-VCE, MK-STYX-VCE and BRRN1-VCE are indeed breast tumor associated variants. These variants were also evaluated in an independent set of 40 breast tumor samples to biologically validate the VCE over expression in tumor samples as compared to normal samples. All data were correlated with clinical and histopathological samples features, and some significative associations were found, such as the expression of estrogen (ER+) and progesterone (PgR+) receptors with TRIM37-VCE. Although an increase of the experimental data is required for the complete exploration of this study, the results suggest 3 splicing variants that are over expressed in ductal carcinoma of the breast, and are candidates for molecular markers.

Diversificação de cenários de ensino e trabalho sobre necessidade/problemas da comunidade / Diversification of education and work scenarios over the problems/needs of the community

O presente artigo discute algumas licoes extraidas de processos de ensino-aprendizagem no ambito de experiencias da Rede UNIDA, em que a diversificacao de cenarios significa a incorporacao e a inter-relacao entre metodos didaticos pedagogicos, a utilizacao de tecnologias e habilidades cognitivas e psicomotoras nos processos de trabalho, considerando-se a dinamica social da saude e da doenca e a valorizacao de preceitos morais e eticos oritentadores e condutas individuais e coletivas. Sao abordados os antecedentes historicos das praticas em cenarios diversificados, os fatores que lhe sao favoraveis, os seus atores e alguns dos seus resultados

Análisis epidemiológico de la fiebre hemorrágica venezolana período 1994-2000 / Epidemiological analysis of the venezuelan haemorrhagic feves period 1994-2000

Estudio de caso del Virus identificado como agente etiológico de la enfermedad, presentado el Municipio Guanarito Estado Portuguesa, Venezuela

Rede UNIIDA: breve historico, concepcao, organizacao e estrategia de acao / UNIIDA (Union University Unity and Teaching Care Integration) Network: brief history, conception, organization and action plan

A Rede UNIIDA (Uniäo Universidade Unidade e Integraçäo Docente-Assistencial) é oriunda do processo de amadurecimento das experiências da rede IDA e do Projeto UNI, desenvolvidas no Brasil desde as decadas de 70 e 90, respectivamente. Relata a maneira como foi concebida a forma de atuacao e como esta organizada. Conclui que a Rede UNIIDA inicia a sua construçäo, na expectativa de ampliar o seu papel social agregando novos parceiros, que compartilhem o desejo de promover mudanças nos modelos de ensino e de atençäo a saúde no Brasil (MMSC)