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Introduction: Contact investigation is a proven intervention for tuberculosis (TB) case finding and prevention. Although widely endorsed by national public health authorities and the World Health Organization, many countries struggle to implement it effectively. The objective of the study is to describe and characterize the barriers and facilitators of TB contact investigation in Cali, Colombia from the perspective and experience of the key stakeholders involved. Methods: We collected data from group discussions during two workshop sessions with clinic and public health staff involved in TB contact investigation (June 2019 and March 2020 respectively) and semi-structured interviews with TB cases and their household contacts (July 2019 to April 2020). We undertook an inductive thematic analysis with the RADaR technique to characterize the barriers and facilitators of the TB contact investigation process. Results: The two workshops included 21 clinics and 12 public health staff. We also conducted 26 semi-structured interviews with TB cases and their household contacts. Using thematic analysis, we identified four common themes: Healthcare Operations, Essential Knowledge, Time Limitations and Competing Responsibilities, and Interpersonal Interactions. The main barriers to conducting household visits were low data quality, stigma and mistrust, safety concerns for health workers, and limited resources. The main barriers to TB uptake by contacts were competing responsibilities, low TB risk perceptions among contacts, and difficulty accessing diagnostic tests for contacts. In contrast, good communication and social skills among health workers and accurate TB knowledge facilitated successful household visits and TB test uptake, according to key stakeholders. Conclusion: This study provides a deeper understanding of TB contact investigation barriers and facilitators in a high-prevalence urban setting in a middle-income country from the perspective and experience of key stakeholders. The study shed light on the barriers that hinder household contacts engagement and TB test uptake such as issues of systemic capacity and TB knowledge. Also, highlighted facilitators such as the importance of interpersonal communication skills among health workers in the public and private sector. The insights from this study can serve as a valuable resource for public health organizations seeking to enhance their contact investigation efforts and improve TB control in similar settings.

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RESUMEN La actividad microbiológica es esencial para mantener la calidad de los suelos y los sistemas agroforestales surgen como alternativa, para el manejo agroecológico y sostenible del suelo. Este estudio evaluó el efecto de las variedades de café (Caturra y Catuaí) y de las fluctuaciones por épocas climáticas, sobre algunas propiedades microbiológicas del suelo, como indicadores de calidad, en un sistema agroforestal. Las muestras de suelo, se tomaron en la capa superior, a 5cm de profundidad, durante un año en épocas seca y lluviosa. Las mayores emisiones de CO2, se observaron en los suelos con la variedad Catuaí, en época seca. Los niveles de carbono de la biomasa microbiana (Cmic) no mostraron diferencias entre las variables estudiadas. Los valores obtenidos para el cociente metabólico (qCO2) fueron mayores en los suelos con la variedad Catuaí, mientras que el cociente microbiano (qMic) presentó los mayores valores en los suelos con la variedad Caturra. El cociente de eficiencia metabólica (qCO2.Corg -1) no mostró diferencias entre los suelos estudiados; sin embargo, sus niveles fueron más altos para las muestras tomadas durante la época seca. La microbiota del suelo denotó sensibilidad a los cambios por época climática de muestreo y tipo de variedad cultivada, mientras que las constantes ecofisiológicas resultaron sensiblemente apropiadas, para evaluar la calidad del suelo.

ABSTRACT The microbiological activity is essential to maintain soil quality, and agroforestry systems emerge as an alternative to the agro-ecological and sustainable land management. This work evaluated the effect of the Caturra and Catuaí coffee varieties, and the weather fluctuation on some microbiological properties of the soil, as indicators of quality in an agroforestry system. The soil samples were taken from the top layer with a depth of 5cm, during a year in dry and rainy seasons. The highest CO2 emissions were observed in soils with the Catuaí variety, in the dry season. On the other hand, Carbon levels of the microbial biomass (Cmic) did not show differences between the variables studied. The values obtained for the metabolic quotient (qCO2) were higher in soils with the Catuaí variety; while the microbial quotient (qMic) presented the highest values in soils with the Caturra variety. The metabolic efficiency ratio (qCO2.Corg-1) showed no differences between the studied soils, however, their levels were higher for the samples taken during the dry season. Soil microbiota showed sensitivity to changes by climatic period and by the type of variety, while the constant eco-physiological were substantially appropriate to evaluate soil quality and sensitive to changes by climatic period and variety of coffee grown in these agroecosystems.

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In the present study, porous silica particles as well as impervious fused-silica wafers and capillary tubes were modified with hydrophilic polymers (hydroxylated polyacrylamides and polyacrylates), using a surface-confined grafting procedure based on atom transfer radical polymerization (ATRP) which was also surface-initiated from α-bromoisobutyryl groups. Initiator immobilization was achieved by hydrosilylation of allyl alcohol on hydride silica followed by esterification of the resulting propanol-bonded surface with α-bromoisobutyryl bromide. Elemental analysis, IR and NMR spectroscopies on silica micro-particles, atomic force microscopy, ellipsometry and profilometry on fused-silica wafers, as well as CE on fused-silica tubes were used to characterize the chemically modified silica substrate at different stages. We studied the effect of monomer concentration as well as cross-linker on the ability of the polymer film to reduce electroosmosis and to prevent protein adsorption (i. e., its non-fouling capabilities) and found that the former was rather insensitive to both parameters. Surface deactivation towards adsorption was somewhat more susceptible to monomer concentration and appeared also to be favored by a low concentration of the cross-linker. The results show that hydrophilic polyacrylamide and polyacrylate coatings of controlled thickness can be prepared by ATRP under very mild polymerization conditions (aqueous solvent, room temperature and short reaction times) and that the coated capillary tubes exhibit high efficiencies for protein separations (0.3-0.6 million theoretical plates per meter) as well as long-term hydrolytic stability under the inherently harsh conditions of capillary isoelectric focusing. Additionally, there was no adsorption of lysozyme on the coated surface as indicated by a complete recovery of the basic enzyme. Furthermore, since polymerization is confined to the inner capillary surface, simple precautions (e.g., solution filtration) during the surface modification process are sufficient to prevent capillary clogging.

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A novel 3-hydroxypropyl (propanol)-bonded silica phase has been prepared by hydrosilylation of allyl alcohol on a hydride silica intermediate, in the presence of platinum (0)-divinyltetramethyldisiloxane (Karstedt's catalyst). The regio-selectivity of this synthetic approach had been correctly predicted by previous reports involving octakis(dimethylsiloxy)octasilsesquioxane (Q8 M8 (H) ) and hydrogen silsesquioxane (T8 H8 ), as molecular analogs of hydride amorphous silica. Thus, C-silylation predominated (∼94%) over O-silylation, and high surface coverages of propanol groups (5 ± 1 µmol/m(2) ) were typically obtained in this work. The propanol-bonded phase was characterized by spectroscopic (infrared (IR) and solid-state NMR on silica microparticles), contact angle (on fused-silica wafers) and CE (on fused-silica tubes) techniques. CE studies of the migration behavior of pyridine, caffeine, Tris(2,2'-bipyridine)Ru(II) chloride and lysozyme on propanol-modified capillaries were carried out. The adsorption properties of these select silanol-sensitive solutes were compared to those on the unmodified and hydride-modified tubes. It was found that hydrolysis of the SiH species underlying the immobilized propanol moieties leads mainly to strong ion-exchange-based interactions with the basic solutes at pH 4, particularly with lysozyme. Interestingly, and in agreement with water contact angle and electroosmotic mobility figures, the silanol-probe interactions on the buffer-exposed (hydrolyzed) hydride surface are quite different from those of the original unmodified tube.

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Analyte recovery is an important figure to assess protein adsorption on fused-silica capillaries. In 1991, Regnier et al. estimated recovery by assuming the loss of analyte from adsorption and thus the decrease in peak area measured by two detectors to be proportional to the length of the capillary section between them. In this report, we closely examine this concept and its adaptation to commercial CE instruments to determine protein recovery. We hypothesize that, once a steady-state migration is reached, protein adsorption is a first-order process with respect to protein concentration and surface density of adsorbing sites. This hypothesis is shown to be valid over a reasonably wide range of capillary effective length and, as a result, protein recovery decreases exponentially with the migrated distance. However, unlike the traditional recovery figure obtained through a conventional spike process, protein recovery measured by this approach does not have the same merit since it is strongly dependent from capillary dimensions and applied electric field. Nevertheless, protein recovery and the slope of the logarithmic protein peak area versus length plot are useful figures to compare protein adsorption on different capillary surfaces. Several literature reports dealing with the application of Regnier concept to calculate protein recovery are discussed.

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The aortic arch branches variations have called the attention of several authors, who have handled studies and classifications, both human and in different animals. The common trunk, which is between the brachiocephalic trunk and the common left carotid artery, is the most common variation. We conducted a descriptive and randomized study of the presence of the trunk mentioned before, trying to establish the possible relationship between this variation and the distribution plates of atheroma. The lumen observation makes it possible to define and check the distribution of the ostium, among the common ostium and the ones with common trunks. Regarding the plates of atheroma, it was found that there is a slight prevalence in common trunks cases, with respect to the classics (no variety) or the ones who had common ostium. In all cases, the presence of a plaque in the distal aortic arch was certified near the left subclavian artery. The knowledge of the existence of the common trunk sets up an act of academic interest, as practice interventions and diagnostic imaging and clinical work, since the presence of the common trunk might be related to the prevalence of the plates of atheroma at the level of its origin.

Las variaciones de las ramas del arco aórtico han llamado la atención de diversos autores, quienes han realizados estudios y clasificaciones, tanto en humanos, como en diferentes animales. El tronco común, entre el tronco braquiocefálico y la arteria carótida común izquierda, es la variación más frecuente. Realizamos un estudio descriptivo y randomizado de la presencia del mencionado tronco, tratando de verificar la posible relación entre dicha variación y la distribución de placas de ateroma. La observación luminal permitió precisar, entre los casos de ostios comunes y aquellos con troncos comunes, y comprobar la distribución de los ostios. En cuanto a las placas de ateroma, se observó una leve prevalencia en los casos de troncos comunes respecto de los clásicos (sin variedad) o de los que presentaron ostios comunes. En todos los casos se verificó la presencia de una placa en el arco aórtico distal, inmediato a la arteria subclavia izquierda. El conocimiento de la existencia del tronco común, constituye un hecho de interés académico, como práctico en intervencionismo, diagnóstico por imagen y la clínica. La presencia del tronco común pareciera estar relacionada con cierta prevalencia de placas de ateroma a nivel de su origen.

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Two children were sent to the catheterization laboratory for transcatheter closure of patent ductus arteriosus (PDA). During the intervention, cineangiogram revealed associated aberrant right subclavian artery (ARSA). Both patients had left-sided aortic arch. The first patient was sent to surgery after one unsuccessful attempt to close the PDA due to the proximity of the ARSA and also because of other concomitant cardiac lesions. We successfully treated the second patient by closing the PDA with a Nit-Occlud® PDA occlusion device (Pfm Medical, Carlsbad, California). Similar mirror cases of PDA closure with aberrant left subclavian artery and right aortic arch have been reported. Anatomic features, as well as the technique and management of the procedure, are discussed here.

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Two synthetic schemes to produce a hydride-modified support that serves as an intermediate for the preparation of bonded phases for liquid chromatography (LC) and capillary electrophoresis (CE) are investigated. The strategies differ in the silane reagent utilized (trichlorosilane (TCS) or triethoxysilane (TES)) and the manner water is incorporated into the reaction. In the first approach, TCS in toluene reacts with a previously humidified silica substrate so that the reaction is confined to the silica surface. In the second approach, TES and a small amount of aqueous HCl are dissolved in THF, and this hydrolysate is diluted by a great factor in cyclohexane, prior to reaction with the silica substrate. Atomic force microscopy (AFM) images of the hydride film on wafers revealed that, unlike the traditional approach that produced a patchy coating, both new methods provided a homogeneous layer on the substrate's surface. IR and NMR spectra from porous silica particles clearly confirmed a successful surface modification. AFM and water contact angles (WCA) were used to examine the effect of dilution of the TES hydrolysate in cyclohexane on the trend of the film to polymerize on wafers and found that a dilution factor of at least 100 is required to attain a molecularly thin hydride layer. WCA and CE also revealed a strong susceptibility of the hydride silica intermediate to hydrolyze, even at low pH. Compared to TCS, the lower reactivity and volatility of TES resulted in a much more desirable experimental approach.

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The cephalic vein shows a scarce description, especially in the deltopectoral triangle, and its ending in the axillary vein. Some established considerations such as "superficial vein, located in the deltopectoral groove, accompanied by braches of the thoraco-acromial artery, which ends in the deltopectoral triangle in the shape of fan arch" should be reevaluated. Procedures difficulties in the la catheterization deserve for a more accurate description. A descriptive, prospective study is performed. The goal is to determine the anatomy of the cephalic vein in the deltopectoral triangle, with a special focus on the characteristics concerning its path and type of termination. Findings show that the cephalic vein is deeply placed and has a different path than that of an arch (circumference segment on a level) with a retro pectoral path and an acceptable diameter, thus useful and safe in the catheterization processes.

La vena cefálica ha sido poco descrita en el triángulo deltopectoral y su terminación en la vena axilar. Algunas consideraciones la señalan como "la vena superficial, situada en el surco deltopectoral, acompañada de ramas de la arteria toraco-acromial, que termina en el trígono deltopectoral en forma de arco de ventilador" por lo que debe ser reevaluado. Debido a las dificultades en los procedimientos de cateterización la vena cefálica merece una descripción más exacta. Se realizó un estudio descriptivo prospectivo con el objetivo de determinar la anatomía de la vena cefálica en el trígono deltopectoral, dando especial atención a sus trayecto y tipo de terminación. Los resultados demostraron que la vena cefálica está localizada profundamente en el surco deltopectoral, presenta un trayecto distinto a un arco (segmento de la circunferencia de un nivel) siendo este trayecto retropectoral y un diámetro aceptable, por lo tanto, útil y seguro para los procesos de cateterización.

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In CE practice, conditioning of the capillary tube with strong base, acid, or both in sequence, has been recognized as essential to obtain reasonable precision in electroosmotic mobility (EOM), and consequently, in the migration times of analytes. This report focuses on the comparative study of three different approaches for capillary conditioning: etching with HF, etching with NaOH, and leaching with HCl after NaOH treatment. EOM-based measurements, including the hysteresis effect that characterizes the dependence of EOM with pH, were used to evaluate the conditioned silica surface. Additionally, indirect inspection of the conditioned surface was carried out by examining the electrophoretic profile of the cationic probe Ru(bpy)(3) (2+), known to strongly interact with the ionized silica surface while displaying no significant acid-base activity. It was shown that, once conditioned and prior to any CE measurement, extensive rinse of the capillary with the running electrolyte at high flow rate was essential to attain relatively rapid re-equilibration of the tube with the fluid. Insufficient rinse with the running electrolyte would result in negatively biased EOM measurements and significant drift in migration times. It was also established that relatively high flow rates of 1 M NaOH conditioning solution (4-5 column volumes per minute) was required to attain capillaries with reproducible electrophoretic performance within a reasonable conditioning time (typically, 1 h). In addition to relatively more extensive rehydroxylation of the silica surface, evidenced by the highest EOM values obtained, the sequential use of NaOH-etching and HCl-leaching provided better precision than HF-etching or NaOH-etching alone.

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La infecciones causadas por el complejo Entamoeba histolytica/Entamoeba dispar son de distribución cosmopolita. E. histolytica es la única especie patógena, pero la diferenciación con E. dispar se hace por métodos bioquímicos. Este trabajo tuvo como finalidad detectar rápidamente la adhesina específica de E. histolytica para diferenciarla de E. dispar en materia fecal, así como determinar la frecuencia del complejo E. histolytica/E. dispar en una población rural de Cundinamarca. En el puesto de salud de La Virgen, Quipile, Cundinamarca, se recolectaron 140 muestras de materia fecal de niños y adultos y se analizaron por el método de concentración (formol-éter) para determinar la frecuencia del complejo E. histolytica/E. dispar. Las 23 muestras positivas para este complejo (16,42 por ciento) se valoraron con la metodología de la prueba de ELISA para la detección de adhesina; se obtuvo una frecuenca de 8,69 por ciento (2/23) de E. histoytica. A 19 pacientes positivos para el complejo E. histolytica/E. dispar se les realizó ELISA para la detección de anticuerpos en sangre contra E. histolytica con resultado negativo. Extrapolando los resultados de la detección de adhesina a la población total de este estudio (2/140), se obtuvo una frecuencia de 1,42 por ciento de E. histolytica. La ventaja de la prueba de ELISA para la detección de adhesina es su fácil ejecución que permite hacer un diagnóstico rápido para instaurar un manejo adecuado. Se recomienda la realizació de estudios de prevalencia a nivel nacional

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Objetivo: evaluar dos técnicas que miden la IgA antitoxoplasma para utilización como pruebas de referencia, en un programa de control de la toxoplasmosis materna. Tipo de estudio: evaluación de prueba diagnóstica. Sitio donde se realizó el estudio: Laboratorio de referencia para Toxoplasmosis, Universidad del Quindio y Laboratorio de Parasitología del Hospital Maison Blanche, Reims, Francia. Sueros analizados y procedencia: veintinueve sueros de pacientes con criterios serológicos de toxoplasmosis reciente, 46 sueros de pacientes con infección toxoplásmatica crónica y 43 sueros de pacientes con ausencia de criterios serológicos de infección toxoplasmática. Todos los sueros procedian de madres que participan en el programa de control prenatal del Instituto Seccional de Salud del Quindio. Resultados: la técnica ELISA-IgA con un punto de corte a un índice de fijación de 1,1 tuvo sensibilidad de 72 por ciento para detectar casos agudos y especificidad de 76 por ciento en sueros con infección crónica y de 92 por ciento en sueros no reactivos. La técnica ISAgA-IgA en el mismo grupo de pacientes demostró sensibilidad de 97 por ciento para detectar casos agudos y especificidad de 97 por ciento en sueros de pacientes crónicos y de 100 por ciento en sueros no reactivos. A partir de estos datos se realizó una simulación de los valores predictivos positivos y negativos que se pueden esperar en las condiciones epidemiológicas del Departamento del Quindio. Conclusión: el conjunto de datos obtenidos demuestra que en sueros de madres colombianas la mejor técnica para utilización comp prueba de referencia en un programa de control de la toxoplasmosis materna es la prueba ISAgA-IgA

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Se presenta un caso de de hidranencefalia (ausencia casi completa de la corteza cerebral en la cual los hemisferios cerebrales están reemplazados por líquido), como forma de manifestación de una toxoplasmosis congénita adquirida por la madre al tercer mes de gestación. Esta forma clínica se observa en regiones con alta incidencia de la infección congénita la cual debe ser tenida encuenta como causa de hidranencefalia.

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