Silicon-Based Glucose Oxidase Working Electrode for Glucose Sensing.

We created a glucose oxidase (GOx) working electrode on a silicon-on-insulator (SOI) wafer for glucose sensing. The SOI wafer was electrically connected to a copper wire, and the GOx was immobilized onto the hydrophilized SOI surface via silanization with aminopropyltriethoxysilane and glutaraldehyde. Electrochemical analysis (i.e., cyclic voltammetry) was employed to identify the sensing mechanism and to evaluate the performance of these SOI-GOx glucose sensors. The response of the SOI-GOx working electrode was significantly higher in the presence of oxygen than that without oxygen, indicating that a hydrogen peroxide pathway dominated in our SOI-GOx electrode. The height of cathodic peaks increased linearly with the increase of glucose concentrations up to 15 mM. The SOI-GOx working electrode displayed good stability after more than 30 cycles. On the 133rd day after the electrode was made, although the response of the SOI-GOx electrode dropped to about one-half of its original response, it was still capable of distinguishing different glucose concentrations. This work suggests that the SOI-GOx working electrode that we developed might be a promising candidate for implantable glucose sensors.

Kaempferol inhibits Entamoeba histolytica growth by altering cytoskeletal functions.

The flavonoid kaempferol obtained from Helianthemum glomeratum, an endemic Mexican medicinal herb used to treat gastrointestinal disorders, has been shown to inhibit growth of Entamoeba histolytica trophozoites in vitro; however, the mechanisms associated with this activity have not been documented. Several works reported that kaempferol affects cytoskeleton in mammalian cells. In order to gain insights into the action mechanisms involved in the anti-amoebic effect of kaempferol, here we evaluated the effect of this compound on the pathogenic events driven by the cytoskeleton during E. histolytica infection. We also carried out a two dimensional gel-based proteomic analysis to evidence modulated proteins that could explain the phenotypical changes observed in trophozoites. Our results showed that kaempferol produces a dose-dependent effect on trophozoites growth and viability with optimal concentration being 27.7 µM. Kaempferol also decreased adhesion, it increased migration and phagocytic activity, but it did not affect erythrocyte binding nor cytolytic capacity of E. histolytica. Congruently, proteomic analysis revealed that the cytoskeleton proteins actin, myosin II heavy chain and cortexillin II were up-regulated in response to kaempferol treatment. In conclusion, kaempferol anti-amoebic effects were associated with deregulation of proteins related with cytoskeleton, which altered invasion mechanisms.

Inteligencia humana: un acercamiento teórico desde dimensiones filosóficas y psicológicas / Human intelligence: a theoretical approach from philosophical and psychological dimensions

Se ofrecen algunas concepciones y criterios que orienten y estimulen a los estudiantes y profesionales a pensar en la temática de la inteligencia humana, necesariamente polémica y que requiere la discusión y la investigación colectivas. Por ello no se propone decir la última palabra, sino promover el pensamiento y la discusión en torno a esta temática que tan importante para todos los seres humanos en general y en particular para los profesionales de la Psicología, Defectología entre otros. Para la realización de este trabajo se tienen en cuenta los criterios de varios autores en el empleo del método cualitativo de la teoría fundamentada que se encarga de describir teorías, conceptos, hipótesis y proposiciones con vista a desarrollar una perspectiva teórica en un solo estudio, en este caso sobre determinantes psicológicos de la automedicación en el adulto mayor por medio de la revisión bibliográfica según los métodos del nivel teórico de investigación: análisis-síntesis, inducción-educción, modelación y enfoque sistémico que permitieron hacer las valoraciones pertinentes y tener en cuenta los enfoques de otros investigadores(AU)

Some concepts and criteria are offered to guide and encourage students and professionals to consider the issue of human intelligence, necessarily controversial and require collective discussion and research. Therefore we propose not the last word, but to promote thought and discussion on this subject which is so important for all human beings in general and in particular for professionals in psychology, Defectology among others. To carry out this work we had on the criteria of several authors in the use of qualitative method of grounded theory that handles describe the theories, concepts, hypotheses and propositions with a view to developing a theoretical perspective in a single study, our case on psychological determinants of self-medication in the elderly through the literature review by the methods of theoretical research: analysis-synthesis, induction, deduction, modeling and systemic approach that allowed us to make appropriate assessments and consider the approach of other researchers(AU)

The flavonoid (-)-epicatechin affects cytoskeleton proteins and functions in Entamoeba histolytica.

Human amoebiasis is an intestinal disease with a global distribution. Due to reports of parasite resistance or susceptibility reduction to metronidazole treatment, there is a renewed interest for the search of new molecules with antiamoebic activity. The flavonoid (-)-epicatechin that was isolated from the Mexican medicinal plant Geranium mexicanum HBK has an in vitro activity against E. histolytica trophozoites, however its molecular effects have been poorly documented. Using a proteomic approach based on two-dimensional gel electrophoresis and mass spectrometry (ESI-MS/MS) analysis, we evidenced that E. histolytica cytoskeleton proteins exhibit differential abundance in response to (-)-epicatechin treatment. Moreover, functional assays revealed modification on pathogenic mechanisms associated with cytoskeleton functionality, namely, adhesion, migration, phagocytosis and cytolysis. Consequently, these data suggested that (-)-epicatechin could affect virulence properties of this human pathogen. BIOLOGICAL SIGNIFICANCE: This work contributes with some advances in the action mechanisms involved in the antiamoebic effect of the flavonoid (-)-epicatechin. We found that this flavonoid has an unusual effect on trophozoites growth that is dependent of its concentration. Additionally, we reported that (-)-epicatechin affects mainly amebic cytoskeleton proteins, which results in alteration on important virulence mechanisms, like adhesion, migration, phagocytosis and cytolysis. This study provides new knowledge about a potential alternative therapy directed to the treatment of amoebiasis.

Ultrastructural changes on Entamoeba histolytica HM1-IMSS caused by the flavan-3-ol, (-)-epicatechin.

The flavan-3-ol, (-)-epicatechin has been previously identified as the most important antiamoebic compound among the extracts from two medicinal plants: Rubus coriifolius and Geranium mexicanum. Here we report the effects of epicatechin on Entamoeba histolytica morphology, analyzed by electronic microscopy. E. histolytica trophozoites were incubated for 48 h at 37 degrees C in the presence of 1.9 microg/mL epicatechin and processed for electronic microscopy analysis. Epicatechin induced nuclear and cytoplasmic changes in the treated trophozoites. These morphological alterations are identical to the cellular changes experienced by E. histolytica trophozoites undergoing programmed cell death (PCD), suggesting that epicatechin could be an alternative compound to treat amoebiasis.

Perspectiva psicosocial del climaterio femenino / Psychosocial perspective of the feminine climaterio

Se realizó una revisión bibliográfica a cerca del abordaje del climaterio femenino con un análisis histórico del pensamiento científico en torno al tema, desde una perspectiva psicosocial. Se muestran los aspectos que constituyen campos de acción obligados para la Psicología de la Salud como son: La conceptualización teórica del periodo del climaterio con el encuadre de las variables psicológicas y sociales que en él concomitan y la formación de una nueva imagen de ésta etapa del ciclo vital femenino entre la población general y los trabajadores de la salud en particular (AU)

Informe de un caso según el modelo de campo / A case report according to the field pattern

En este trabajo se aborda la problemática de estudio de casos como modalidad de la investigación cualitativa, utilizada en el campo de la psicología. Además se fundamenta con aspectos teóricos introductorios como el conductismo, los procesos de condicionamiento muy precisos de estímulos y de respuestas del comportamiento humano, así como la psicología del aprendizaje y sus relevantes contribuciones a la Ciencia del comportamiento, entre otros criterios; y por último se demuestra como aplicar metodológicamente el modelo de campo en el estudio de casos (AU)

Calidad de vida de pacientes egresados de la Unidad de Cuidados Intensivos / Life quality in patients discharged of Intensive Care Unit

Se realiza un estudio descriptivo, con el objetivo de caracterizar la calidad de vida de una muestra (n=100) de pacientes egresados de la Unidad de Cuidados Intensivos del Hospital General Docente ¨Dr Agostinho Neto¨, de Guantánamo, durante el año 2000. Se evalúa la calidad de vida física por el método de Rivera, y la psíquica, mediante la prueba de completamiento de frases. Se precisa la calidad de vida social a través de la prueba de funcionamiento familiar por el método de Cresta Freijomil, y la incorporación y mantenimiento de la actividad laboral de acuerdo con los criterios de Rivera; al integrar los tres tipos de calidad de vida se establece la biopsicosocial. Además, se relaciona esta última con la edad, el sexo y el diagnóstico al egreso de la unidad. Se concluye que la mayoría de los enfermos tienen una calidad de vida física no útil al egreso (86,0 por ciento), debido, fundamentalmente, a la intolerancia al esfuerzo (96,0 por ciento) y la dependencia farmacológica (74,0 por ciento). Al egreso de los pacientes, éstos reflejan menor alteración de la calidad de vida psíquica (17,0 por ciento) y social (48,0 por ciento), y se afectan en menor medida. La calidad de vida biopsicosocial se afecta en el 93,0 por ciento, principalmente por las limitaciones de la calidad de vida física. En general, la calidad de vida mejora ostensiblemente en la mayoría de los pacientes cuando ellos se evalúan a los doce meses de egresados(AU)