La respuesta de shock térmico y el dimorfismo en Leishmania

Protozoa of the Leishmania genus are intracellular parasites having two different stages, promastigote and amastigote, which are present during their life cycle in the invertebrate host and the mammal host respectively. During its life cycle, the parasite suffers dramatic temperature changes and the transformation success between one and the other form is crucial for its survival and reproduction. The response of the organisms to temperature or heat shock response has been well studied in Leishmania, promastigotes having been obtained at 26°C and amastigotes at 35°C respectively, and their reconversion when the temperature is increased or lowered has been demonstrated. These changes in parasite morphology are accomplished by biochemical and molecular variations with differences in enzyme activity and protein synthesis. These processses increase the production of heat shock proteins, specifically HSP70 and HSP83, which continue to be expressed as pari of the Leishrnania amastiyotes as a way of adaptation to vertebrate host environment. At a molecular level, it has been demonstrated that almost al1 heat shock proteins structural genes are arranged in tandem repetition, being transcribed in polycystronic RNA and finally processed by poly-adenylation and trans-splicing. Nevertheless, it has not been possible to identify any transcription promoter in these parasites. Furthermore, studies of transcriptional regulation have demonstrated that the regulation of heat shock proteinsr gene éxpression in Leishmania occurs by post-transcriptional processes. This demonstration has marked a fundamental difference between Leishmania and the other non-protozoal eucariotes.Los protozoos del género Leishmania son parásitos intracelulares con dos formas distintas de desarrollo, promastigote y amastigote, las cuales se presentan durante su ciclo de vida entre el hospedero invertebrado y el hospedero mamífero vertebrado, respectivamente. Durante esie ciclo el parásito experimenta grandes variaciones de temperatura y el éxito de la transformación entre una y otra forma es crucial para su supervivencia y reproducción. La respuesta de los organismos a la temperatura o respuesta de shock térmico ha sido bien estudiada en Leishmania, obteniendo promastigotes a 26°C y amastigotes a 35°C y demostrando su reconversión al aumentar o disminuir la temperatura. Estos cambios en la morfología están acompañados de cambios bioquímicos y moleculares, con diferencias en las actividades enzimáticas y en la síntesis proteica, la cual incrementa la producción de proteínas de shock térmico, específicamente HSP70 y HSP83, las cuales permanecen constitutivamente expresadas en los amastigotes de Leishmania como una forma de adaptación al medio ambiente del hospedero vertebrado. A nivel molecular se ha demostrado que la mayoría de los genes estructurales de estas proteínas están dispuestos en repeticiones en serie los cuales se transcriben en RNA policistrónicos y son posteriormente procesados por poliadenilación y transsplicing; sinembargo no ha sido posible identificar ningún promotor de la transcripción en estos parásitos. Además, los estudios de regulación transcripcional han demostrado que la regulación de la expresión del gen de shock térmico en Leishmania ocurre por procesos postranscripcionales, hecho que ha marcado una diferencia fundamental entre Leishmania y los demás eucariotes no protozoo

Rhodnius pallescens (Barber, 1932) y Trypanosoma cruzi en Urabá

We report the first finding of Rhodnius pallescens infected with Trypanosoma cruzi in the Urabá region (Antioquia). The insect was a female identified with the keys of Lent and Wigodzinsky. It was confirmed by the lnstituto Nacional de Salud in Colombia. Fertile eggs were obtained and the new born insects were used to establish a colony of R. pallescens in the Instituto Colombiano de Medicina Tropical in Medellín, The faeces were found positive for Trypanosoma cruzi. The parasite underwent biochemical identification in the Centro Internacional de Entrenamiento e Investigaciones Médicas (CIDEIM, Cali).Se informa por primera vez para la zona de Urabá (Antioquia), la presencia de Rhodnius pallescens infectado con Trypanosoma cruzi El ejemplar era una hembra que fue identificada con las claves de Lent y Wigodzinsky y confirmada en el lnstituto Nacional de Salud. De ella se obtuvieron huevos fértiles que fueron usados para establecer una colonia en el lnstituto Colombiano de Medicina Tropical; presentaba, además, heces positivas para T. cruzi, parásito que fue identificado bioquímicamente en el Centro Internacional de Entrenamiento e Investigaciones Médicas (CIDEIM, Cali)

Fenoles totales y actividad antioxidante en hojas de dos especies colombianas del género Meriania (melastomataceae)

Se estudiaron las hojas de las especies Merianiaspeciosa y Meriania nobilis, obteniendoextractos de diferente polaridad, a los que seles realizaron diversas pruebas cualitativas. Sedeterminó el contenido de fenoles totales y seevaluó la actividad captadora de radicales conDPPH (FRS50: capacidad captadora de radicalesque reduce en un 50% al radical DPPH)en microplacas de 96 pozos. Este estudiodeterminó que las dos especies presentan unabuena actividad antioxidante. Los extractosque mayor actividad antioxidante mostraronfueron: butanol con FRS50 de 7,6 ± 0,8 y 23,4± 2,4; acuoso con FRS50 de 28,5 ± 2,9 y 63,0± 2,6 y hexano 2 con FRS50 de 17,0 ± 2,6 y18,2 ± 2,5 mg/L, para las especies M. speciosay M. nobilis respectivamente. Los extractosque presentaron un alto contenido de fenolestotales fueron: metanol 2 con valor de 0,47 ±0,06 y 0,40 ± 0,03 mg equivalentes de ácidogálico (EAG)/g extracto seco (ES) y el extractoacuoso: 0,16 ± 0,06 y 0,12 ± 0,03 mg EAG/gES para las especies M. speciosa y M. nobilisrespectivamente. El extracto butanólico de laespecie M. speciosa mostró la mayor actividadantioxidante con un FRS50 de 7,6 mg/L ± 0,8,este valor es comparable con el valor halladopara la quercetina FRS50: 4,2 mg/L ± 0,4, loque indica que este extracto es promisorioen el contenido de metabolitos secundariosque exhiben actividad antioxidante y parala fabricación de productos agroquímicos,cosméticos y farmacéuticos

Understanding the relationship between soundscape and landscape features in a Tropical Andean environment, Colombia

The acoustic component of the landscape (soundscape) has been suggested as an indicator of landscape conditions as it has been related to physical, biological and anthropogenic features of the local environment. Despite of acoustic indices have been used as measurements of soundscape complexity, their relationship with landscape features has shown to be highly variable and not direct. This relationship has not been examined on the tropical Andes then it is not clear if soundscape can be a reliable indicator of landscape conditions. In this study, we assess the relationship between 14 acoustic indices and landscape conditions in an area on the northern Andes of Colombia. This region is highly fragmented and characterized for a highly diverse community of animals and plants thus representing an excellent opportunity to test such relationship. Soundscape recordings were obtained from 31 randomly selected sites surveyed among May and July 2017. A Song Meter SM4 device was deployed at each site for five consecutive days, and programmed to collect 1-min recordings every 15 minutes for a total of 95 samples per day. Recordings were obtained as monaural 16 bits and at a sampling rate of 22.05 kHz. Out of 14 indices, we calculated 9 non-correlated acoustic indices for each 1-min recording and selected the maximum value per hour to estimate the hourly average over the five days at each site. Thirteen landscape features were derived from satellite images and metrics describing vegetation, fragmentation, water availability, terrain, and soil attributes at 100 m radius around each site. Indices did not present a similar pattern of variation with respect to landscape conditions. Acoustic evenness (AE) and temporal entropy (TE) indices were related to changes in terrain conditions, while acoustic diversity index (ADI) was associated to fragmentation. The bioacoustic index (BI), acoustic complexity index (ACI), and the number of peaks (NP) were positively related with water availability. Our results suggest that in Andean environments specific acoustic indices could be connected to particular aspects of landscape

Automating biological monitoring on the Northern Andes of South America: combining biology and machine learning for conservation

The northern Andes in South America harbors one of the most diverse biological diversity on the planet. Yet, it is one of the most threatened regions as a result of habitat fragmentation, invasive species, agriculture and cattle grazing, and global climate change. It is therefore critical to implement robust conservation strategies and effective monitoring plans. In the region, biological monitoring relies on traditional methods such as direct observation and capture. These methods are expensive and require a large effort specially for rare species. As an alternative, automated passive bioacoustics allow to obtain large amounts of data both in time and space and in comparison, with traditional methods at low cost. The main challenge in passive monitoring is to handle and analyze these rivers of information in order to obtain meaningful results from acoustic data. We have implemented a passive bioacoustic monitoring since 2012 on the northern Andes in Colombia, a highly diverse region in the Neotropics. Our goals are two fold: first, we want to develop analytical strategies to process large amounts of sound files and second we are interested in answering biological questions from individuals to the landscape. As a result of this monitoring, we have developed a machine learning algorithm based on syllable recognition to automatically identify frog species (Ecol. Inf. 24: 200-209). We also have developed an algorithm to estimate the amount of rain from acoustic recordings (Ecol. Ind. 75:95-100). We have answered biological questions ranging from acoustic niche partitioning, interaction of traditional community indices with acoustic indices, and association of acoustic indices with landscape features. Now, we are using passive monitoring to fit complex occupation models and to determine assembling rules in anuran communities. In addition, we are assessing acoustic indices aiming to develop tools with more functions for soundscape analysis (Ecol. Inf. 45:16-25). We show how the continuous feedback between biologists and engineers will spike the implementation and analysis of passive monitoring in imperiled tropical hotspots

Dengue en el embarazo: efectos en el feto y el recién nacido.

The risk of dengue virus infection during pregnancy has increased due to the current rash of frequent and severe dengue epidemics. The effects of dengue virus in the fetus and newborn children have been studied only superficially and with contradictory results. Therefore, a retrospective cohort study was conducted in Medellin, Colombia, to describe the fetal and postnatal effects of dengue virus infection acquired during pregnancy. Twenty-two babies born from mothers who suffered dengue during the epidemics of 1998 were compared with babies from non-infected mothers. In the exposed cohort, three premature births occurred, three children suffered from fetal anomalies and four children were born with low weight. In the non-exposed children, none of these problems were found. Psychomotor development was normal in both groups. Only the low weight subgroup was statistically significant (Fisher test, p = 0.045). These results suggested that the children from women with dengue during pregnancy present low weight, greater frequency of premature birth and increased fetal distress. A larger sample is necessary to confirm these results.El riesgo de infección por el virus del dengue durante el embarazo se está incrementando ante mayores y más severas epidemias, y las consecuencias sobre el feto y el recién nacido han sido poco estudiadas y, en otros casos, los resultados han sido contradictorios. Por esta razón, se realizó en Medellín un estudio de cohorte retrospectiva, cuyo objetivo fue determinar los efectos que produce el dengue durante el embarazo sobre el feto y el recién nacido. En dicho estudio se evaluaron 22 recién nacidos hijos de mujeres que presentaron dengue durante la epidemia de 1998 y se compararon con 24 recién nacidos, hijos de mujeres embarazadas sin dengue. En la cohorte con dengue se encontraron 3 niños prematuros, 3 niños con sufrimiento fetal y 4 niños con bajo peso al nacer. En la cohorte no expuesta no se encontraron niños con estos problemas. El desarrollo psicomotor fue normal en ambos grupos. De las observaciones anteriores, sólo fue estadísticamente significativa la frecuencia de niños con bajo peso al nacer (prueba exacta de Fisher, p=0,045). Estos resultados preliminares muestran que los recién nacidos de madres que sufrieron dengue durante la gestación tuvieron riesgo de bajo peso al nacer y presentaron con mayor frecuencia prematurez y sufrimiento fetal, aunque se requiere aumentar el tamaño de la muestra para confirmar estos resultados. Sin embargo, es necesario estrechar la vigilancia a las madres embarazadas con dengue dados los efectos nocivos sobre la evolución del recién nacido

Flavonoides del extracto isopropanol-agua de tibouchina ciliaris (melastomataceae)

Los compuestos: Quercetina-3’-O-Ramnosido (compuesto 2) y Kaempferol-7-Op- cumaroil han sido aislados de las hojas secas de Tibouchina ciliaris, junto con otros compuestos como Kaempferol (compuesto 1) y Ácido elágico, sus estructuras fueron elucidadas por análisis de RMN, HPLC-DAD y MS, y por comparación con datos bibliográficos. El Kaempferol presentó una concentración mínima inhibitoria (CMI) de 512 μg/mL contra Escherichia coli

Universidad y sociedad. Extensión del conocimiento

Este libro hace un análisis de la educación y propone migrar de una institución educativa a una organización de extensión del conocimiento (Mejía, 2011) toma más fuerza cada día, ya que obtiene una participación más activa en su actuar, y no solo se circunscribe a mejorar la gestión de las áreas funcionales de mercadeo, docencia, investigación, extensión, financiera, tecnología y administración (Gutiérrez, 2011), también cuenta con una visión más sistémica para conseguir la felicidad social y de las personas que conforman la organización educativa

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries