15 research outputs found

    Actividad neurotóxica y cambios ultraestructurales en musculos causados por el veneno de la araña viuda marrón Latrodectus geometricus

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    Brown widow spider (Latrodectus geometricus) venom (BrWSV) produces few local lesions and intense systemic reactions such as cramps, harsh muscle pains, nausea, vomiting and hypertension. Approximately 16 protein bands under reducing conditions and ~ 14 bands under non-reducing conditions on a 12.5% sodium dodecyl sulfate-polyacrylamide gel electrophoresis were observed. Neurotoxic clinical manifestations were confirmed in vivo, while proteolytic activity was demonstrated on gelatine film. Severe ultrastructural damages in mice skeletal muscles were observed at 3, 6, 12 and 24 h postinjection with at total of 45 µg of venom protein. Infiltration of eosinophils and ruptures of the cellular membranes were observed in the muscles along with swelling of the nuclear cover and interruption of the collagen periodicity. Altered mitochondrias and autophage vacuoles, nuclear indentation and mitochondria without cristae, slight increment of intermyofibrillar and subsarcolemic spaces and myelinic figures formation were also observed. In the capillary, endothelial membrane unfolding into the lumen was noticed; along with myelinic figures compatible with a toxic myopathy. Swollen sarcotubular systems with lysis of membrane, intense mitochondria autophagia and areas without pinocytic vesicles were observed. Swollen mitochondria surrounded by necrotic areas, myofibrillar disorganization and big vacuolas of the sarcotubular system, degenerated mitochondrium with formation of myelinic figure was seen. Glycogenosomes with small particulate, muscle type glycogen was noticed. Autophagic vacuole (autophagolysosomes) and necrotic areas were also noticed. These damages may be due to interactive effects of the multifactorial action of venom components. However, Latrodectus geometricus venom molecules may also be utilized as neuro therapeutic tools, as they affect neuronal activities with high affinity and selectivity. To our knowledge, the present study is the first ultrastructural report in the literature of muscle injuries and neurological and proteolytic activities caused by BrWSV.El veneno de la araña viuda marrón (Latrodectus geometricus) produce pocas lesiones locales pero intensas reacciones sistémicas, tales como calambres, dolores musculares severos, nauseas, vómitos e hipertensión arterial. Se observaron ~ 16 bandas de proteina bajo condiciones reducidas y ~14 bandas bajo condiciones no reducidas en electroforesis en geles de poliacrilamida al 12.5%. Las manifestaciones neurotóxicas clínicas fueron confirmadas in vivo, mientras que la actividad proteolítica fue demostrada en una placa de gelatina. Los músculos de ratón se estudiaron durante las 3, 6, 12 y 24 horas después de ser inyectados con 45 µg de proteina de veneno. Los músculos fueron seriamente dañados por este veneno. Se demostró una infiltracción de células eosinofílicas y rupturas de membranas celulares en tejido muscular, al mismo tiempo un fuerte incremento de la membrana nuclear y una interrupción de la periodicidad del colágeno. Se observaron daños en la mitocondria y sin cristaes, vacuolas autofágicas e indentación nuclear. Se notó un aumento de la luz de los espacios intermiofibrilares y subsarcolemicos. En los capilares fue visible un desdoblamiento de la membrana endotelial hacia el lúmen vascular. Del mismo modo, fue visto un hinchamiento del sistema sarcotubular con lisis de las membranas; intensa autofagia de mitocondrias y áreas sin vesículas pinocíticas. Fue además observado, glucogenosomas con glucogeno particulado. Se observaron vacuolas autofágicas (autofagolisosomas) y áreas de necrosis. Estos daños podrían ser atribuídos a los efectos interactivos de una acción multifactorial de los componentes del veneno

    Effects of Photomixotrophic Conditions on Plants of Eucalyptus Urograndis Propagated in Temporary Immersion Bioreactors

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    Eucalyptus is one of the crop, which has been investigated with commercial purposes in the world. There are more than 500 species, being the Eucalyptus urograndis one of the most important, because of its intensive use in the production of wood pulp to make papers. The multiplication by means of temporary immersion bioreactors (TIB) is among the present techniques to obtain higher productions of the pulp to satisfy the demands of the market. The effects of the photomixotrophic crop were studies during the elongation of the propagation of shoots in the TIB in order to increase the quality of them. This process consisted of the use of 30 g L-1 combined with two concentration of CO2 (350 and 1200 µmol mol) and two flows of photosynthetic photon flux (PPF= 80 and 250 µmol m-2s-1). The higher percentage of suitable plants were found with the treatment of high PPF (250 µmol m-2 s-1) and 1 200 µmol mol of CO2. The photosynthetic capacity of propagated shoots was of 64% of the adult plants. Also was observed that photomixotrophic conditions reduced the stressed environment that is imposed by the growing in vitro. The catabolic activity in the enzymes of the metabolism of carbon was also reduced, increasing the activity of the Sucrose Phosphate Synthase

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

    Tutorial multimedia para el manejo de aspectos formales de los trabajos de investigación

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    El objetivo del estudio consistió en el diseño de un prototipo de tutorial multimedia para la instrucción en el manejo de los aspectos formales de los documentos de trabajos de grado cumpliendo con las normativas vigentes de una institución de educación superior pública del área metropolitana de Caracas, Venezuela. El método empleado correspondió al de Proyecto Factible descrito por la Universidad Pedagógica Experimental Libertador UPEL (2006), como una propuesta de acción para resolver un problema práctico o satisfacer una necesidad. Para el diseño de instrucción se siguió el modelo de Aguilar (2005), quien lo define como un proceso apoyado en un enfoque sistémico que organiza los componentes de naturaleza instruccional para satisfacer necesidades y metas educativas. Se consideró el enfoque conductual del aprendizaje como base del modelo pedagógico dada la naturaleza tutorial del prototipo y el uso de las Tecnologías de Información y Comunicación (TIC) para apoyar el diseño. La técnica de recolección de datos empleada fue la entrevista a un informante clave (Nieves, 2010); los datos fueron categorizados e interpretados para concluir que un 90 % de los trabajos recibidos presentan inconsistencias de forma, lo que justificó el desarrollo del referido prototipo de tutorial multimedia. Palabras Clave: Trabajos de investigación, aplicación multi- media, Tecnologías de Información y Comunicación (TIC

    Caso inusual de difteria cutánea con compromiso mucoso y síndrome del vértecx orbitario

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    La difteria es una enfermedad prevenible por vacunas. En la actualidad existe un brote en nuestro país que se inició en abril de 2016. Desde entonces se han descrito casos en diferentes sitios del país predominantemente de la forma faríngea. La difteria cutánea no ha sido reportada en este brote. A nivel mundial el compromiso simultáneo en piel y mucosas, no ha sido descrito. La paciente cuya enfermedad describimos aquí es un caso de difteria de presentación atípica que se inicia con expresión cutánea y evoluciona a compromiso nasal, ocular y faríngeo con complicaciones severas en la órbita ocular expresadas como un síndrome del vértex orbitario, en una paciente con diabetes mellitus tipo 2 no controlada, que tuvo una evolución tórpida que la llevó a la muerte. Se revisa la literatura.Diphtheria is a vaccine-preventable disease. Actually, there is an outbreak in Venezuela since April 2016. Cases in different parts of the country have been described, predominantly pharyngeal. Cutaneous diphtheria has not been reported in this outbreak. The simultaneous presentation of the cutaneous form with mucosal involvement has not been described in the revised literature. We present a case of diphtheria with atypical presentation that begins with cutaneous expression and evolves to nasal, ocular and pharyngeal compromise with severe complications of the orbit, expressed in an orbital vertex syndrome in a patient with type 2 diabetes mellitus, who had a torpid evolution that led her to death. The literature is reviewed
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