Molecular detection of intestinal parasites in a rural community of Colombia: A one health approach to explore potential environmental-zoonotic transmission.

AIMS: Protozoan and helminth parasitic infections pose significant public health challenges, especially in developing countries with rural populations marked by suboptimal hygiene practices and socio-economic constraints. The parasites are the etiological agents of these infections and have a notably elevated global prevalence. Therefore, this study focuses on estimating the frequency and transmission dynamics of several parasitic species, including Blastocystis, Giardia, Cryptosporidium spp., Entamoeba histolytica, Ascaris lumbricoides, Trichuris trichiura, Taenia spp. and hookworms, within a rural community in southwest Colombia with a particular emphasis on the One Health framework, considering environmental and zoonotic transmission potentials. METHODS AND RESULTS: This study involved the analysis of 125 samples, encompassing human participants (n = 99), their domestic pets (dogs) (n = 24) and water sources (n = 2). Parasite detection was carried out utilizing a combination of microscopy and molecular techniques. Furthermore, the characterization of Blastocystis subtypes (STs) was achieved through Oxford Nanopore sequencing of the rRNA-18S gene. The investigation also entailed the examination of potential associations between intestinal parasitism and various sociodemographic factors. Results revealed a high frequency of parasitic infections when employing molecular methods, with Blastocystis (n = 109/87%), Giardia (n = 20/16%), Ancylostoma duodenale (n = 28/22%), Ancylostoma ceylanicum (n = 7/5.6%), E. histolytica (n = 6/4.8%), Cryptosporidium spp. (n = 12/9.6%) and even Taenia (n = 1/0.8%) detected. Cryptosporidium spp. was also identified in water samples. Coinfections were prevalent, with 57% (n = 70) of samples exhibiting single-parasite infections and 43% (n = 53) showing various degrees of polyparasitism, emphasizing the complexity of transmission dynamics. Blastocystis subtyping, conducted via Oxford Nanopore sequencing, revealed a diversity of subtypes and coexistence patterns, with ST2 being the most prevalent. CONCLUSIONS: This research underscores the importance of using molecular techniques for frequency estimation, particularly emphasizing the relevance of zoonotic transmission in parasitic infections. It highlights the significance of the One Health approach in comprehending the circulation of parasites among animals, humans and environmental sources, thereby directly impacting public health and epidemiological surveillance.

Perioperative Management of Painful Phantom Limb Syndrome: A Narrative Review and Clinical Management Proposal.

OBJECTIVE: Painful Phantom Limb Syndrome (PPLS) occurs in 50 to 80% of patients undergoing amputation, having a great impact on quality of life, productivity and psychosocial sphere. The objective of this review is to summarize the pharmacological and non-pharmacological strategies, surgical optimization, and provide a multidisciplinary approach aimed at reducing the incidence of chronic pain associated with PPLS in patients undergoing limb amputation. METHODS: A narrative review was carried out using Medline, Pubmed, Proquest, LILACS and Cochrane, searching for articles between 2000 and 2021. Articles describing the epidemiology, pathophysiological considerations, and current treatments were selected after a screening process. RESULTS: A multidisciplinary and multimodal approach is required in PPLS, and should include the use of regional techniques, and adjuvants such as NSAIDs, ketamine, lidocaine and gabapentinoids. In addition, an evaluation and continuous management of risk factors for chronic pain in conjunction with the surgical team is necessary. CONCLUSION: The current literature does not support that a single technique is effective inthe prevention of PPLS. However, adequate acute pain control, rehabilitation and early restoration of the body scheme under a multidisciplinary and multimodal approach have shown benefit in the acute setting.

The Operative Link on Gastritis Assessment (OLGA) system as a marker for gastric cancer and dysplasia in a Colombian population at risk: A multicenter study / Sistema OLGA (Operative Link on Gastritis Assessment) como marcador para cáncer gástrico y displasia en una población colombiana de alto riesgo: estudio multicéntrico.

Introduction. The OLGA system has been proved to be useful in Asia and Europe as a risk marker of gastric cancer. However, its usefulness in high-risk populations in Colombia is still unknown. Objective. To assess potential associations between the OLGA staging system and an increased risk of gastric cancer and dysplasia in a high-risk Colombian population and to establish diagnostic capacity of the scale to assess the risk. Materials and methods. We carried out a multicenter study including patients with cancer and dysplasia (cases) and patients with atrophy and intestinal metaplasia (controls). A total of 506 patients were recruited from three centers in an area with a high risk population in Colombia. The endoscopic and histopathologic studies were evaluated according to the Sydney system and the OLGA staging system proposed by Rugge. The effect of each variable on the disease (gastric cancer and dysplasia) was evaluated using bivariate and multivariate models. Statistical significance was set considering a p value inferior to 0.05. Results. Advanced stages of the OLGA system (III-IV) were associated with a higher risk of dysplasia and gastric cancer (adjusted OR = 8.71; CI95% = 5.09-14.9; p=0.001), sensitivity=54.9%, specificity=89.3% and positive likelihood ratio=5.17. Conclusions. The OLGA staging system is a risk marker for gastric cancer and dysplasia in the studied population. We recommend its implementation to improve the timely diagnosis and follow-up of patients with the highest cancer risk.

Introducción. En Asia y Europa, el sistema OLGA ha sido útil como marcador de riesgo de cáncer gástrico. Sin embargo, su utilidad en poblaciones de alto riesgo en Colombia aún se desconoce. Objetivo. Establecer si los estadios OLGA se asocian con un mayor riesgo de cáncer y displasia en una población de alto riesgo en Colombia y determinar la capacidad diagnóstica de la escala para evaluar dicho riesgo.Materiales y métodos. Se realizó un estudio multicéntrico con pacientes con cáncer gástrico y displasia (casos), y pacientes con atrofia y metaplasia intestinal (controles), provenientes de tres centros de una zona de alto riesgo de cáncer gástrico en Colombia. Se incluyeron 506 pacientes cuyo estudio endoscópico e histopatológico fue realizado mediante el sistema de Sydney y la estadificación de OLGA propuesta porRugge. El efecto de cada variable de interés sobre la enfermedad (cáncer gástrico y displasia) se evaluó mediante modelos bivariados y multivariados. Un valor de p menor de 0,05 se consideró estadísticamente significativo.Resultados. Los estadios elevados del sistema OLGA (III-IV) se asociaron con un mayor riesgo de displasia y cáncer gástrico (OR ajustado = 8,71; IC95 % = 5,09-14,9; p=0,001) con una sensibilidad del 54,9 %, especificidad del 89,3 % y una razón de probabilidad positiva de 5,17.Conclusiones. El estadio OLGA es un marcador de riesgo de cáncer gástrico y displasia en la población de estudio. Se recomienda su implementación como estrategia para optimizar el diagnóstico oportuno y el seguimiento de pacientes con mayor riesgo.

Sistema OLGA (Operative Link on Gastritis Assessment) como marcador para cáncer gástrico y displasia en una población colombiana de alto riesgo: estudio multicéntrico

Introducción. En Asia y Europa, el sistema OLGA ha sido útil como marcador de riesgo de cáncer gástrico. Sin embargo, su utilidad en poblaciones de alto riesgo en Colombia aún se desconoce. Objetivo. Establecer si los estadios OLGA se asocian con un mayor riesgo de cáncer y displasia en una población de alto riesgo en Colombia y determinar la capacidad diagnóstica de la escala para evaluar dicho riesgo. Materiales y métodos. Se realizó un estudio multicéntrico con pacientes con cáncer gástrico y displasia (casos), y pacientes con atrofia y metaplasia intestinal (controles), provenientes de tres centros de una zona de alto riesgo de cáncer gástrico en Colombia. Se incluyeron 506 pacientes cuyo estudio endoscópico e histopatológico fue realizado mediante el sistema de Sydney y la estadificación de OLGA propuesta por Rugge. El efecto de cada variable de interés sobre la enfermedad (cáncer gástrico y displasia) se evaluó mediante modelos bivariados y multivariados. Un valor de p menor de 0,05 se consideró estadísticamente significativo. Resultados. Los estadios elevados del sistema OLGA (III-IV) se asociaron con un mayor riesgo de displasia y cáncer gástrico (OR ajustado = 8,71; IC95 % = 5,09-14,9; p=0,001) con una sensibilidad del 54,9 %, especificidad del 89,3 % y una razón de probabilidad positiva de 5,17. Conclusiones. El estadio OLGA es un marcador de riesgo de cáncer gástrico y displasia en la población de estudio. Se recomienda su implementación como estrategia para optimizar el diagnóstico oportuno y el seguimiento de pacientes con mayor riesgo.

Introduction. The OLGA system has been proved to be useful in Asia and Europe as a risk marker of gastric cancer. However, its usefulness in high-risk populations in Colombia is still unknown. Objective. To assess potential associations between the OLGA staging system and an increased risk of gastric cancer and dysplasia in a high-risk Colombian population and to establish diagnostic capacity of the scale to assess the risk. Materials and methods. We carried out a multicenter study including patients with cancer and dysplasia (cases) and patients with atrophy and intestinal metaplasia (controls). A total of 506 patients were recruited from three centers in an area with a high risk population in Colombia. The endoscopic and histopathologic studies were evaluated according to the Sydney system and the OLGA staging system proposed by Rugge. The effect of each variable on the disease (gastric cancer and dysplasia) was evaluated using bivariate and multivariate models. Statistical significance was set considering a p value inferior to 0.05. Results. Advanced stages of the OLGA system (III-IV) were associated with a higher risk of dysplasia and gastric cancer (adjusted OR = 8.71; CI95% = 5.09-14.9; p=0.001), sensitivity=54.9%, specificity=89.3% and positive likelihood ratio=5.17. Conclusions. The OLGA staging system is a risk marker for gastric cancer and dysplasia in the studied population. We recommend its implementation to improve the timely diagnosis and follow-up of patients with the highest cancer risk.

SARS-CoV-2 RBD-Tetanus Toxoid Conjugate Vaccine Induces a Strong Neutralizing Immunity in Preclinical Studies.

Controlling the global COVID-19 pandemic depends, among other measures, on developing preventive vaccines at an unprecedented pace. Vaccines approved for use and those in development intend to elicit neutralizing antibodies to block viral sites binding to the host's cellular receptors. Virus infection is mediated by the spike glycoprotein trimer on the virion surface via its receptor binding domain (RBD). Antibody response to this domain is an important outcome of immunization and correlates well with viral neutralization. Here, we show that macromolecular constructs with recombinant RBD conjugated to tetanus toxoid (TT) induce a potent immune response in laboratory animals. Some advantages of immunization with RBD-TT conjugates include a predominant IgG immune response due to affinity maturation and long-term specific B-memory cells. These result demonstrate the potential of the conjugate COVID-19 vaccine candidates and enable their advance to clinical evaluation under the name SOBERANA02, paving the way for other antiviral conjugate vaccines.

Frequency of anesthetic overdose with mean alveolar concentration-guided anesthesia at high altitude.

This study reported the frequency of anesthetic overdose measured with the bispectral index in a high altitude city (Bogotá-Colombia, 2600 meters above sea level). We assembled a prospective cohort of patients. Preoperative variables were described, and 10 minutes after the surgical incision, bispectral index, mean alveolar concentration, mean arterial pressure, and oxygen saturation were recorded. Bispectral index was classified as superficial (60), adequate (40-60), and deep (> 40). Mean alveolar concentration was classified as low (< 0.8), normal (0.8-1.2), and high (> 1.2). We included 50 patients. The mean age of the patients was 36.3 ± 13.5 years; 48% were male and 78% were categorized as ASA I. Mean values of mean alveolar concentration and bispectral index were 1.14 ± 0.18 and 38.66 ± 6.9, respectively. Frequency of anesthetic overdose measured with bispectral index was 54% and only 20% with mean alveolar concentration. In total, 78% of patients received normal mean alveolar concentration values, and among these patients, 49% had deep bispectral index levels and 51% were adequate. There was no correlation between mean alveolar concentration and bispectral index (Pearson r = 0.161, P = 0.246) or between bispectral index and mean arterial pressure (Pearson r = 0.367, P = 0.08). All patients older than 60 years exhibited deep bispectral index levels, and although we did not identify a correlation between age and bispectral index, a tendency was observed (Pearson r = -0.087, P = 0.538). Safe and effective anesthesia overdose could be a common phenomenon. Bispectral index-guided anesthesia could be a helpful and reliable tool in the assessment and prevention of anesthesia overdose at high altitude. The study was approved by the ethics committee of the Fundación Cardioinfantil-Instituto de cardiología, Bogota, Colombia (approved number: 312017).

Relación entre desarrollo de los programas para la gestión del uso de antimicrobianos, apropiabilidad y consumo de antibióticos en hospitales de Argentina / Relationship between the antimicrobial stewardship program development, appropriateness and antimicrobial consumption in Argentinean hospitals

Introducción: La implementación de Programas para la Optimización de Uso de Antimicrobianos (PROAs) ha resultado una estrategia útil para mejorar los resultados asistenciales, de manera segura y costo-efectiva, reduciendo el desarrollo de la resistencia a los antimicrobianos.Objetivo: Estimar la relación entre nivel de desarrollo de los PROAs, apropia-bilidad y consumo de antimicrobianos en hospitales ArgentinosMaterial y métodos: Entre Jul-2016 y Ene-2017, 111 hospitales condujeron una autoevaluación del nivel de desarrollo de sus PROAs usando un instrumen-to basado en los lineamientos del CDC (0 a 100 puntos), además de un cor-te de prevalencia para evaluar la apropiabilidad de las prescripciones de an-timicrobianos y su consumo mensual [Dosis Diarias Definidas (DDD) c/100 días-paciente]. Para la comparación de estos indicadores, los centros fueron dicotomizados tomando como punto de corte el percentilo 75 (p75) de la au-toevaluación.Resultados: La comparación entre hospitales con puntaje ≥p75 vs.

Objective: To assess the association between the level of AMS programs development, appropriateness and antimicrobial consumption in Argentinean hospitalsMaterial and methods: Between Jul-2016 and Jan-2017, 111 hospitals performed a self-assessment survey of their AMS programs using a standardized tool based on CDC recommendations (0­100 scale). In addition, the appropriateness of antimicrobial prescription was measured through one-day prevalence study using specific criteria. The monthly consumption of a group of antimicrobials was calculated using Defined Daily Doses (DDD) per 100 patient-days. To assess the relationship between the level of AMS programs development and the appropriateness and antimicrobial consumption indicators, participating centers were grouped into two categories by using the 75th percentile (75thp) of the self-assessment scoreResults: Comparison between hospitals with score ≥75thp vs <75thp showed significant differences in all indicators analyzed (self-assessment score: 51.6 vs 25.4; diff. 26.2; 95%CI 30.3 to 22.0, p<0.000; surgical prophylaxis: ≤ 24 hs 64.8% vs 52.3%; diff. 12.5%; 95%CI 5.1% to 20.0%, p<0.002; compliance with guidelines: 77.6% vs 47.0%; diff. 30.6%; 95%CI 28.1% to 33.0%, p<0.000; prospective audit with feedback: 69.4% vs 46.8%; diff. 22.6%; 95%CI 20.0% to 25.2%, p<0.000; antimicrobial consumption: 114.8 DDDs vs 259.2 DDDs; diff.­144.4; 95%CI ­140.6 to ­148.2, p<0.000)Conclusions: Hospitals with higher self-assessment score showed better appropriateness and consumption antimicrobial indicators, reinforcing the relevance of an effective implementation of AMS programs

Frecuencia de mutaciones de la nitrorreductasa RdxA de Helicobacter pylori para la activación del metronidazol en una población del departamento del Cauca, Colombia / Frequency of Helicobacter pylori nitroreductase RdxA mutations for metronidazole activation in a population in the Cauca Department, Colombia

RESUMEN Introducción. La resistencia al metronidazol es un factor clave relacionado con el fracaso del tratamiento contra la infección por Helicobacter pylori asociada, principalmente, con mutaciones en la nitrorreductasa RdxA. A pesar de su importancia, los estudios sobre esta proteína son aún incipientes en Popayán, Colombia. Objetivo. Evaluar la frecuencia de las mutaciones en la nitrorreductasa RdxA en una población de pacientes con enfermedad gastrointestinal por H. pylori. Materiales y métodos. El ADN de 170 biopsias gástricas se amplificó mediante reacción en cadena de la polimerasa (PCR) para detectar las mutaciones en la nitrorreductasa RdxA. Se analizaron las secuencias traducidas a aminoácidos y se compararon con la cepa de referencia 26695. Resultados. La frecuencia de mutaciones de la nitrorreductasa RdxA en la población de estudio fue de 78 %. Su distribución más frecuente se detectó en las posiciones D59N (en 153 muestras), R131K (en 101 muestras), R90K (en 97 muestras), A118T (en 42 muestras), I160F (en 32 muestras), H97T (en 26 muestras) y en los codones de parada Q50*; D59*; E75*; C159* y I160* en cinco, una, tres, diez y seis muestras, respectivamente. El genotipo de virulencia más frecuente fue el vacAs1/m1 negativo para cagA (48,6 %). Conclusiones. La gran frecuencia de mutaciones en la nitrorreductasa RdxA en aislamientos de H. pylori en Popayán sugiere que los tratamientos empíricos con metronidazol no serían una opción válida para su erradicación en pacientes de la población estudiada.

ABSTRACT Introduction: Resistance to metronidazole is a key factor associated with Helicobacter pylori treatment failure. Even though resistance is mostly associated with RdxA nitroreductase mutations, studies of this H. pylori protein in Popayán (Colombia) are still incipient. Objective: To evaluate the frequency of mutations in the RdxA nitroreductase in a population of patients with H. pylori-positive gastrointestinal disease. Materials and methods: We amplified the DNA of 170 gastric biopsies by PCR to detect mutations in the RdxA nitroreductase. An analysis of DNA sequences translated into amino acid sequences was done and then compared to the reference strain 26695. Results: The frequency of RdxA nitroreductase mutations in this study population was 78%. Its most frequent distribution was found in positions D59N (153 samples), R131K (101 samples), R90K (97 samples), A118T (42 samples), I160F (32 samples) and H97T (26 samples), and meaningful stop codons Q50*, D59*; E75*, C159* and I160* in five, one, three, ten and six samples, respectively. The most common virulence genotype was vacAs1/m1 cagA negative (48.6 %). Conclusions: The high frequency of RdxA nitroreductase mutations in H. pylori isolates in Popayán (Colombia) indicates that empirical therapy with metronidazole may not be a valid option for the eradication of H. pylori in patients of the studied population.

[Frequency of Helicobacter pylori nitroreductase RdxA mutations for metronidazole activation in a population in the Cauca Department, Colombia].

INTRODUCTION: Resistance to metronidazole is a key factor associated with Helicobacter pylori treatment failure. Even though resistance is mostly associated with RdxA nitroreductase mutations, studies of this H. pylori protein in Popayán (Colombia) are still incipient. OBJECTIVE: To evaluate the frequency of mutations in the RdxA nitroreductase in a population of patients with H. pylori-positive gastrointestinal disease. MATERIALS AND METHODS: We amplified the DNA of 170 gastric biopsies by PCR to detect mutations in the RdxA nitroreductase. An analysis of DNA sequences translated into amino acid sequences was done and then compared to the reference strain 26695. RESULTS: The frequency of RdxA nitroreductase mutations in this study population was 78%. Its most frequent distribution was found in positions D59N (153 samples), R131K (101 samples), R90K (97 samples), A118T (42 samples), I160F (32 samples) and H97T (26 samples), and meaningful stop codons Q50*, D59*; E75*, C159* and I160* in five, one, three, ten and six samples, respectively. The most common virulence genotype was vacAs1/m1 cagA negative (48.6 %). CONCLUSIONS: The high frequency of RdxA nitroreductase mutations in H. pylori isolates in Popayán (Colombia) indicates that empirical therapy with metronidazole may not be a valid option for the eradication of H. pylori in patients of the studied population.

Hallazgos periféricos en pacientes con degeneración macular relacionada con la edad avanzada / Peripheral findings in patients with age-related macular degeneration

Objetivo: Explorar la asociación entre la presencia de cambios degenerativos en la periferia retiniana de pacientes con diagnóstico clínico de Degeneración Macular Relacionada con la Edad (DMRE), evaluados con fotografía de fondo de ojo a color (FP), angiografía fluoresceínica (FA) y autofluorescencia (FAF), y las etapas más avanzadas de la enfermedad. Métodos: Estudio descriptivo, transversal con intención analítica, en el cual se evaluaron las imágenes de campo amplio obtenidas mediante FP, FA, y FAF con oftalmoscopía de láser confocal con la Optomap 200TX, de todos los pacientes con diagnóstico clínico de DMRE, para un total de 94 pacientes (188 ojos) que aceptaron participar en el estudio, y que acudieron a la Clínica Oftalmológica de Antioquia (CLOFAN) entre agosto y septiembre del 2016, con diagnóstico clínico de DMRE. La variable desenlace fue presencia de DMRE avanzada. Resultados: Se incluyeron imágenes de 130 ojos de 70 pacientes. La edad media fue 72,1 años (DE±9,5 años). El 20,8% de los pacientes eran pseudofáquicos. El 52,9%, 32,9% y 37,1% tenían historia de HTA, dislipidemia y hábito tabáquico positivo, respectivamente. Se observó una asociación estadísticamente significativa entre DMRE avanzada y el antecedente de DMRE en la familia (p<0,05, OR=2,4, IC=1,1-6,2), la presencia de cambios degenerativos en la periferia en FP (p<0,001, OR=5,71, IC=1,8-17,7), FA (p<0,05, OR=3,1, IC=0,9-10,1) y FAF (p<0,001,OR=10,52, IC=0,63-8,13). En el análisis multivariado solo la presencia de lesiones en FP se mantuvo asociada significativamente con la presencia de DMRE avanzada. Conclusiones: La presencia de cambios degenerativos en periferia se asocian 4,71 veces más con la DMRE avanzada, y por tanto, la presencia de éste tipo de lesiones podría ser predictora de progresión. Se requieren estudios prospectivos que permitan determinar causalidad y contribuir a la comprensión de la patogénesis de la DMRE.

Purpose: To explore the association between the presence of degenerative changes in the retinal periphery of patients with clinical diagnosis of AMD, evaluated with color fundus photography (FP), fluorescein angiography (FA) and autofluorescence (FAF), and the more advanced stages of the disease. Methods: A descriptive, cross-sectional study with analytical intent, in which wide fi eld images obtained by PF, AF, and FAF using confocal laser ophthalmoscopy with Optomap 200TX, all patients with a clinical diagnosis of AMD, for a total of 94 patients (188 eyes) who attended the Clínica oftalmológica de Antioquia (CLOFAN) between August and September of 2016, with clinical diagnosis of AMD, were analyzed. Th e outcome variable was advanced age related macular degeneration. Results: Images of 130 eyes of 70 patients were included. Th e mean age was 72.1 years (SD ± 9.5 years). It was observed that 20.8% were pseudophakic. 52.9%, 32.9% and 37.1% had a history of hypertension, dyslipidemia and a positive smoking habit, respectively. Th ere was a statistically signifi cant association between advanced AMD and family history of AMD (p <0.05, OR=2.4, CI=1.1-6.2), the presence of degenerative changes in the FP (P <.001, OR=5.71, CI=1.8-17.7), FA (p <0.05, OR=3.1, CI=0.9-10.1) and FAF (p <0.001, OR=10.52, CI=0.63-8.13). In the multivariate analysis only the presence of lesions in FP remain signifi cantly associated with the presence of advanced AMD. Conclusions: Th e presence of degenerative changes in periphery are associated 4.71 times more with advanced AMD, and therefore, the presence of this type of lesions could be predictive of progression. Prospective studies are required to determine causality and contribute to the understanding of the pathogenesis of AMD.

La investigación en oftalmología, de los mitos a las posibilidades / Research in ophthalmology, from myths to possibilities

El oftalmólogo del futuro tendrá que redefinir su papel desde la creación de valor para los pacientes y la sociedad; es por esto que el desarrollo científico y la investigación apalancadas en herramientas informáticas epidemiologicas y la colaboración deberán ser parte de nuestro oficio cotidiano. Ya es el momento de cambiar el chip desde las escuelas de medicina y las residencias para especialización; es una realidad que hoy más que nunca la innovación y la investigación deben ser parte de la vida diaria de todo clínico. En investigación existen algunos mitos, que hoy están completamente revaluados, pero que siguen constituyendo barreras para la democratización de la investigación. A continuación me permito enumerar siete de ellos, no son los únicos, pero considero que son quizás los más importantes.

Medida del grosor central coroideo con tomografía óptica coherente de imagen de profundidad mejorada (EDI OCT) en ojos contralaterales de pacientes con coriorretinopatía serosa central (CSC) / Central choroidal thickness measured by enhanced depth imaging (EDI OCT) in fellow eyes of subjects with central serous chorioretinopathy (CSC)

Diseño: Estudio descriptivo y trasversal. Objetivos: Medición del grosor coroideomacular en el ojo contralateral (ojo sano) de pacientes con coriorretinopatía serosa central (CSC), utilizando tomografía óptica coherente de imagen de profundidad mejorada (EDI OCT). Pacientes y métodos: Fueron evaluados 32 ojos de 16 pacientes voluntarios, con diagnostico de coriorretinopatía serosa central (CSC) aguda. Ambos ojos fueron sometidos a estudio de tomografía óptica de dominio espectral con profundidad mejorada (EDI SD-OCT) con el Tomógrafo RTVue® (Optovue, USA). Se realizó escaneo horizontal de alta definición a través de la fóvea, tanto en el ojo afectado, como en el sano contralateral. Se realizaron 5 medidas del grosor coroideo. El promedio del grosor coroideo fue calculado y comparado, entre los ojos con CSC y el ojo contralateral. Resultados: El promedio de edad fue de 40+/-7 (rango entre 29 y 56 años). Quince de los 16 ojos sintomáticos eran derechos. Dos mujeres y 14 hombres. La media del grosor coroideo en el ojo sintomático fue de 470.4+/-35.7µm, y en el ojo contralateral el grosor fue de 413.4+/-47.1µm. La relación entre ambos ojos mostró una alta correlación (0,979) y una correlación estadísticamente significativa (p<0.001). Conclusión: La tomografía óptica coherente de dominio espectral con profundidad mejorada, es una herramienta útil en evaluar el grosor coroideo en pacientes con CSC, donde el grosor coroideo también aparece aumentado en el ojo contralateral.

Design: Descriptive and cross-sectional study. Objective: To measure macular choroidal thickness in fellow eyes of patients with central serous chorioretinopathy, using enhanced depth imaging optical coherence tomography (EDI OCT). Patients and methods: This is a descriptive, cross-sectional study. A total of 32 eyes of 16 patients were evaluated. Sixteen volunteers with acute central serous corioretinopathy (CSC) diagnosis underwent high-definition scanning using SD-OCT (RTVue®, Optovue, USA) with enhanced depth imaging technique (EDI OCT) in both eyes. One horizontal scan across the fovea was selected for each affected and healthy eye, five choroidal thickness measurements were taken. The average choroidal thickness was also calculated and compared among eyes with CSC and fellow eyes. Results: Mean age was 40+/-7 years (range between 29 and 56 years old). Fifteen of 16 symptomatic eyes where right eyes. Two women and 14 men were involved. The mean choroidal thickness in symptomatic eyes was 470.4+/-35.7 µm, and the fellow eyes thickness was 413.4+/-47.1 µm. The matching shows a high correlation (0,979) between paired samples and statistical signifi cance of its correlation (p<0.001). Conclusions: Enhanced depth imaging spectral-domain optical coherence tomography is a helpful tool for assessing choroidal thickness in fellow eyes of patients with CSC, where the choroid is as thickened as in affected eyes.

[Qualitative analysis of water quality deterioration and infection by Helicobacter pylori in a community with high risk of stomach cancer (Cauca, Colombia)]. / Análisis cualitativo del deterioro de la calidad del agua y la infección por Helicobacter pylori en una comunidad de alto riesgo de cáncer de estómago (Cauca, Colombia).

This study looks at aspects of the environmental health of the rural population in Timbío (Cauca, Columbia) in relation to the deterioration of water quality. The information was obtained through participatory research methods exploring the management and use of water, the sources of pollution and the perception of water quality and its relation to Helicobacter pylori infection. The results are part of the qualitative analysis of a first research phase characterizing water and sanitation problems and their relation to emerging infectious diseases as well as possible solutions, which was carried out between November 2013 and August 2014. The results of this research are discussed from an ecosystemic approach to human health, recognizing the complexity of environmental conflicts related to water resources and their impacts on the health of populations. Through the methodology used, it is possible to detect and visualize the most urgent problems as well as frequent causes of contamination of water resources so as to propose solutions within a joint agenda of multiple social actors.

Análisis cualitativo del deterioro de la calidad del agua y la infección por Helicobacter pylori en una comunidad de alto riesgo de cáncer de estómago (Cauca, Colombia) / Qualitative analysis of water quality deterioration and infection by Helicobacter pylori in a community with high risk of stomach cancer (Cauca, Colombia)

Este estudio aborda aspectos de la salud ambiental de la población rural de Timbío (Cauca, Colombia) con relación al deterioro de la calidad del agua. La información se obtuvo mediante métodos de investigación participativa, relacionadas al manejo y uso del agua, fuentes de contaminación y percepción de la calidad del agua y su relación con la infección por Helicobacter pylori. Los resultados forman parte del análisis cualitativo de una primera fase de caracterización de la problemática hídrica y sanitaria y su relación con enfermedades infecciosas emergentes y soluciones comunes, llevada a cabo entre noviembre de 2013 y agosto de 2014. Los resultados de esta investigación se discuten desde un enfoque ecosistémico de la salud humana, que reconoce la complejidad de los conflictos ambientales relacionados con el recurso hídrico y su impacto en la salud de las poblaciones. A través de la metodología empleada, este estudio permitió conocer y visualizar los problemas prioritarios y las causas frecuentes de la contaminación del recurso hídrico, para postular algunas soluciones a través de una agenda compartida con los actores sociales.

This study looks at aspects of the environmental health of the rural population in Timbío (Cauca, Columbia) in relation to the deterioration of water quality. The information was obtained through participatory research methods exploring the management and use of water, the sources of pollution and the perception of water quality and its relation to Helicobacter pylori infection. The results are part of the qualitative analysis of a first research phase characterizing water and sanitation problems and their relation to emerging infectious diseases as well as possible solutions, which was carried out between November 2013 and August 2014. The results of this research are discussed from an ecosystemic approach to human health, recognizing the complexity of environmental conflicts related to water resources and their impacts on the health of populations. Through the methodology used, it is possible to detect and visualize the most urgent problems as well as frequent causes of contamination of water resources so as to propose solutions within a joint agenda of multiple social actors.

Espesor coroideo central medido por tomografía de coherencia óptica de profundidad mejorada en sujetos bajo tratamiento crónico intravítreo con antiangiogénicos / Central choroidal thickness measured by enhanced depht imaging optical coherence tomography in subjects under chronic treatment with intravitreal anti­vascular endothelial growth factor

Objetivos: medir el grosor macular coroideo (GC) y describir las características en el OCT mediante imágenes de profundidad mejorada con tomografía de coherencia óptica (EDI OCT) en pacientes con Degeneración Macular Relacionada con la Edad (DMRE) variedad neovascular, que se sometieron a múltiples inyecciones intravítreas con agentes antiangiogénicos y compararlo con pacientes con DMRE temprana y sanos. Métodos: estudio transversal de casos y controles, apareado por edad y sexo. Un total de 74 ojos de 58 voluntarios, 21 con DMRE húmeda y en tratamiento crónico intravítreo con terapia antiangiogénica (> 10 inyecciones en un período de 30 meses), 21 con DMRE temprana y 32 voluntarios sanos se sometieron a imágenes de alta definición usando SD-OCT (RTVue) con técnica de imagen de profundidad mejorada (EDI OCT). El espesor coroideo promedio se comparó entre los 3 grupos y se realizó una descripción morfológica de los hallazgos. Se llevó a cabo un análisis de regresión lineal univariado para evaluar la relación del GC con la edad, el género, la agudeza visual, el diagnóstico de DMRE y el tratamiento. Resultados: después de controlar las diferencias de edad y sexo, el número de inyecciones de antiangiogénicos no mostró correlación estadísticamente significativa con el grosor macular coroideo (p = 0,689). Entre diferentes variables, la edad fue la única asociada con el GC en el grupo de sanos (p<0.05). El género no mostró relación con el espesor coroideo central en los grupos de DMRE, fue estadísticamente significativo sólo en el grupo de individuos sanos.(p=0.008). La diferencia de grosor coroideo entre los 3 grupos no fue estadísticamente significativa (p=0.064), sólo hubo diferencia estadísticamente significativa (p<0.001) entre el grupo de sujetos con DMRE temprana y los sanos; los pacientes sanos tienen medidas coroideas significativamente más gruesas (234.9 µ IC 95%= 201.5 ­ 268.2) que los otros 2 grupos. Los pacientes con DMRE neovascular mostraron coroides más gruesas en promedio (175.07 µ IC del 95% = 139,3 - 210,8) comparados con aquellos con DMRE temprana (126.3 µ IC 95%= 94.9 ­ 157.6). El valor de GC comparando entre cada medida fue irregular en pacientes con DMRE neovascular, pero fue regular en los pacientes con DMRE temprana y los sanos, mostrando una distribución lineal. Conclusiones: no se encontró correlación entre el número de inyecciones de antiangiogénicos y el GC, lo cual apoya el concepto que las aplicaciones de antiangiogénicos no afectan el GC de acuerdo con lo que otros estudios han indicado. Se observó una diferencia estadísticamente significativa entre el grosor coroideo de los pacientes sanos y los pacientes con DMRE temprana.

Purpose: to measure macular choroidal thickness (CT) and describe EDI OCT characteristics in patients with neovascular AMD who underwent multiple intravitreal injections of anti-VEGF agents, and to compare it with early AMD eyes, and healthy eyes, Methods: this is an age-matched, sexmatched, case-control, cross-sectional study. A total of 74 eyes of 58 patients were evaluated. 21 eyes with neovascular AMD and chronic anti-angiogenic intravitreal treatment (>10 injections in a 30 month period), 21 eyes with early AMD and 32 eyes of healthy volunteers underwent SD-OCT (RTVue) with EDI technique. The average choroidal thickness (CT) was compared with the average CT value of an age-matched, sex-matched, early AMD group and a healthy control group. A description of the morphological findings was done. Univariate linear regression analyses were perform to evaluate choroidal thickness with age, gender, BCVA and AMD diagnosis and treatment. Results: after controlling for age differences the number of Anti VEGF injections showed no statistically significant correlation with macular choroidal thickness (p=0,689). Among different covariates, age was associated with CT (p<0.05) only in the healthy patients group. Gender showed not significant association with CT in AMD groups, it was statistically significant only on the healthy group (p=0.008). There was a difference in CT in the three groups but it was not statistically significant (p=0.064), it only showed a significant difference (p<0.001) between the early AMD and the healthy group. Healthy subjects had significant thicker choroidal measurements (234.9 µ CI 95%= 201.5- 268.2) than the other 2 groups; Patients with neovascular AMD showed thicker choroids (175.07 µ CI 95% =139.3-210.8) compared with early AMD (126.3µ CI 95%=94.9-157.6). The macular CT value was uneven in patients with neovascular AMD, but it was even in patients with early AMD and healthy subjects, showing a linear distribution. Conclusions: no correlation between the number of injections and GC antiangiogenics was found, which supports the concept that antiangiogenic applications do not affect the GC according to what other studies have indicated. A statistically significant difference between the choroid thickness in healthy patients and patients with early AMD was observed.

Atrofia coroidea relacionada con la edad en pacientes hispanos: serie de casos / Age-related choroidal atrophy in hispanics patients: a case series

Propósito: describir los hallazgos y la medición del grosor coroideo subfoveal utilizando tomografía óptica coherente de imagen de profundidad mejorada (EDI OCT), en paciente hispanos con sospecha clínica de atrofia coroidea relacionada con la edad (ARCA). Métodos: estudio descriptivo y trasversal en 17 pacientes con impresión clínica de ARCA, basados en: disminución de la agudeza visual de reciente aparición, alteraciones pigmentarias en la macula, apariencia de fondo de ojo atigrado y atrofia peripapilar a pesar de no ser miope. A todos se les realizó examen oftalmológico completo, que incluía: Agudeza visual mejor corregida (BCVA), biomicroscopía con lámpara de hendidura y evaluación del fondo de ojo bajo dilatación. A estos pacientes se les realizó fotografía digital del fondo de ojo y tomografía óptica coherente de imagen de profundidad mejorada (EDI OCT). Se realizó un total de 5 mediciones del grosor coroideo en el área macular en cada ojo. Resultados: se evaluaron 26 ojos de 14 pacientes, con una edad media de 70,86 años (DS± 8,46 años). El 57.14% fueron mujeres y el 42.86% hombres. El promedio de la agudeza visual fue 20/47 (0,38 LogMAR), el 80.2% presentaron manifestación binocular. La media del grosor coroideo fue 119,53 µm (DS±49,68µm). No hubo correlación estadísticamente signifi cativa entre la BCVA y grosor coroideo (P=0.407). Conclusión: la atrofia coroidea relacionada con la edad es una condición que puede presentarse en pacientes hispanos de edad avanzada. Afecta igualmente a hombres y mujeres, es usualmente bilateral y el grado de adelgazamiento de la coroides no predice la agudeza visual final.

Purpose: to describe the findings and measure the subfoveal choroidal thickness with Enhanced Depth Imaging (EDI) OCT in hispanics subjects with clinical impression of age-related choroidal atrophy (ARCA). Methods: a descriptive and cross-sectional study of 17 subjects with clinical impression of ARCA: based on recently decreased visual acuity, pigmentary alterations in the macula, a tessellated fundoscopic appearance, and peripapillary atrophy despite being not myopic. All patients had a comprehensive ocular examination, including BCVA, biomicroscopic and fundus examination. They underwent color fundus photography and EDI OCT. A total of 5 measurements were took of each eye. Results: twenty six eyes were included from 14 patients, with a mean age 70,86 years (SD ± 8,46 years). The 57,14% were female and 42.86% male. The mean visual acuity was 20/47 (0,38 LogMAR Equivalent), 80.2% had bilateral disease. The mean choroidal thickness was 119,53 µm (SD ± 49,68 µm). There was no statistically significant correlation between BCVA and choroidal thickness (p =0,407). Conclusions: the ARCA is a condition that can be present in elderly Hispanics subjects. Affects equally male and female, it is usually bilateral and the degree of choroidal thinning does not predict the final visual acuity.

[Determination of single nucleotide mutations in the 23S rRNA gene of Helicobacter pylori related to clarithromycin resistance in a population from Cauca, Colombia]. / Determinación de mutaciones de un solo nucleótido en el gen 23S rRNA de Helicobacter pylori relacionadas con resistencia a claritromicina en una población del departamento del Cauca, Colombia.

INTRODUCTION: Antibiotic combination therapy for the eradication of Helicobacter pylori should be based on local resistance patterns. OBJECTIVE: To d etermine the resistance of H. pylori to clarithromycin in a population from Cauca province, through the identification of mutations in the 23S rRNA gene in DNA from gastric biopsies. MATERIALS AND METHODS: A total of 162 patients with functional dyspepsia were included in the study. The 23S rRNA gene and the DNA from 162 gastric specimens were amplified by PCR, and the mutation pattern was identified by direct sequencing. RESULTS: The frequency of clarithromycin resistance was 4%. A2143G mutation was found in four patients (2.46%) and A2142G mutation was found in three patients (1.85%). CONCLUSIONS: Our study shows that the most frequent genotype in H. pylori -positive specimens was A2143G, followed by A2142G. The observed resistance prevalence of H. pylori was low; thus, we consider that clarithromycin treatment is a valid option for H. pylori eradication in the study population.

Determinación de mutaciones de un solo nucleótido en el gen 23S rRNA de Helicobacter pylori relacionadas con resistencia a claritromicina en una población del departamento del Cauca, Colombia / Determination of single nucleotide mutations in the 23S rRNA gene of Helicobacter pylori related to clarithromycin resistance in a population from Cauca, Colombia

Introducción. La terapia antibiótica combinada para la erradicación de Helicobacter pylori debería basarse en los patrones locales de resistencia. Objetivo. Determinar la resistencia de H. pylori a claritromicina en una población del departamento del Cauca mediante la identificación de mutaciones en el gen 23S r RNA en ADN obtenido de biopsias gástricas. Materiales y métodos. Se incluyeron en el estudio 162 pacientes con dispepsia funcional. El gen 23S rRNA se amplificó por PCR y el patrón de mutaciones se identificó por secuenciación directa. Resultados. La frecuencia de resistencia a claritromicina fue de 4 %. La mutación A2143G del gen se encontró en cuatro pacientes (2,46 %) y la mutación A2142G, en tres pacientes (1,85 %). Conclusiones. El estudio encontró que el genotipo más frecuente en los especímenes positivos para H. pylori fue 2143G, seguido por A2142G. La prevalencia observada de resistencia de H. pylori fue baja; por lo tanto, se considera que el tratamiento con claritromicina es una opción válida para la erradicación de H. pylori en la población objeto de estudio.

Introduction: Antibiotic combination therapy for the eradication of Helicobacter pylori should be based on local resistance patterns. Objective: To d etermine the resistance of H. pylori to clarithromycin in a population from Cauca province, through the identification of mutations in the 23S rRNA gene in DNA from gastric biopsies. Materials and methods: A total of 162 patients with functional dyspepsia were included in the study. The 23S rRNA gene and the DNA from 162 gastric specimens were amplified by PCR, and the mutation pattern was identified by direct sequencing. Results: The frequency of clarithromycin resistance was 4%. A2143G mutation was found in four patients (2.46%) and A2142G mutation was found in three patients (1.85%). Conclusions: Our study shows that the most frequent genotype in H. pylori -positive specimens was A2143G, followed by A2142G. The observed resistance prevalence of H. pylori was low; thus, we consider that clarithromycin treatment is a valid option for H. pylori eradication in the study population.

Seasonal variations in zooplankton abundances in the Iturbide reservoir (Isidro Fabela, State of Mexico, Mexico).

This studywas undertaken to quantify the seasonal variations of zooplankton (rotifers, cladocerans and copepods) and selected physico-chemical variables (temperature, pH, conductivity, Secchi disc transparency, dissolved oxygen, ammonia, nitrate and phosphate concentrations) in the Iturbide dam. Monthly zooplankton samples (50 l filtered through 50 microm mesh, in duplicates from each of the 4 stations) were collected from February 2008 to January 2009. Simultaneously physico-chemical variables were measured. The zooplankton samples were fixed in 4% formalin in the field. In general, the temperature ranged from 9 to 16 degrees C, rarely exceeding 20 degrees C. Secchi transparency was nearly 100% since the reservoir was shallow (< 2 m) even during the rainy seasons. Dissolved oxygen was generally high, 13-18 mg l(-1). Nitrate levels (10 to 170 microg l(-1)) were low while phosphates were relatively high (9 to 35 microg l(-1)). The Iturbide reservoir was dominated by rotifer species. We encountered in all, 55 taxa of rotifers, 9 cladocerans and 2 copepods. The rotifer families Trichocercidae and Notommatidae had the highest number of species (7 each) followed by Colurellidae and Lecanidae (6 and 5 species, respectively). Trichocerca elongata, Ascomorpha ovalis, K. americana, K. cochlearis, Lepadella patella and Pompholyx sulcata were the dominant rotifers during the study period. On an annual average, rotifer density ranged between 50-200 ind.(-1). Among crustaceans Chydorus brevilabris and Macrothrix triserialis were most abundant. The maximal density of these cladocerans was about 50 ind. l(-1). Copepods were much lower in numbers (< 20 ind. l(-1)). In general the density of zooplankton was higher during summer months (April to July) than during winter. Shannon-Wiener diversity index varied from 1.0 to 4.3 depending on the site and the sampling period. Based on the data of Secchi transparency and nutrient concentrations, the Iturbide reservoir appeared to be mesotrophic.