Resistance to cephalosporins and quinolones in Escherichia coli isolated from irrigation water from the Rímac river in east Lima, Peru. / Resistencia a cefalosporinas y quinolonas en Escherichia coli aisladas de agua de riego del río Rímac en Lima Este, Perú.

OBJECTIVES.: To evaluate the presence and sensitivity to antimicrobials of Escherichia coli strains isolated from 24 irrigation water samples from the Rimac river of East Lima, Peru. MATERIALS AND METHODS.: The E. coli strains were identified by PCR. Antibiotic susceptibility was processed by the disk diffusion method. Genes involved in extended spectrum beta-lactamases (BLEE), quinolones and virulence were determined by PCR. RESULTS.: All samples exceeded the acceptable limits established in the Environmental Quality Standards for vegetable irrigation. Of the 94 isolates, 72.3% showed resistance to at least one antibiotic, 24.5% were multidrug resistant (MDR) and 2.1% were extremely resistant. The highest percentages of resistance were observed for ampicillin-sulbactam (57.1%), nalidixic acid (50%), trimethoprim-sulfamethoxazole (35.5%) and ciprofloxacin (20.4%). Among the isolates, 3.2% had a BLEE phenotype related to the bla CTX-M-15 gene. qnrB (20.4%) was the most frequent transferable mechanism of resistance to quinolones, and 2.04% had qnrS. It was estimated that 5.3% were diarrheagenic E. coli and of these, 60% were enterotoxigenic E. coli, 20% were enteropathogenic E. coli and 20% were enteroaggregative E. coli. CONCLUSIONS.: The results show the existence of diarrheogenic pathotypes in the water used for irrigation of fresh produce and highlight the presence of BLEE- and MDR-producing E. coli, demonstrating the role played by irrigation water in the dissemination of resistance genes in Peru.Motivation for the study. Aquatic systems, including irrigation water, have been identified as reservoirs of antimicrobial resistance, with few studies in Peru on the presence of Escherichia coli and their levels of virulence and antimicrobial resistance. Main findings. Our results show the presence of E. coli above the established standard for vegetable irrigation water, some with very high levels of antimicrobial resistance. Implications. The presence of ESBL-producing strains of extended-spectrum beta-lactamases and multidrug-resistant E. coli in irrigation water could contribute to the dissemination of resistance genes in Peru, posing a significant threat to public health.

Challenging diagnosis of Plasmodium ovale malaria in a Colombian traveler: the importance of including P. ovale wallikeri in molecular screening.

This study reports a challenging diagnosis of Plasmodium ovale malaria in a Colombian citizen returning from Cameroon. Initial microscopy screenings conducted at two private hospitals yielded conflicting results, with the first showing negative smears and the second diagnosing P. vivax. Subsequent microscopy examinations at two government laboratories identified P. ovale, although the routine species-specific PCR strategy was negative. PCR confirmation was finally obtained when P. ovale wallikeri primers were used. Although P. ovale is not frequently found in Colombia, there is a clear need to include both P. ovale curtisi and P. ovale wallikeri in the molecular diagnostic strategy. Such need stems primarily from their extended latency period, which affects travelers, the increasing number of African migrants, and the importance of accurately mapping the distribution of Plasmodium species in Colombia.

Challenging diagnosis of Plasmodium ovale malaria in a Colombian traveler: the importance of including P. ovale wallikeri in molecular screening

ABSTRACT This study reports a challenging diagnosis of Plasmodium ovale malaria in a Colombian citizen returning from Cameroon. Initial microscopy screenings conducted at two private hospitals yielded conflicting results, with the first showing negative smears and the second diagnosing P. vivax. Subsequent microscopy examinations at two government laboratories identified P. ovale, although the routine species-specific PCR strategy was negative. PCR confirmation was finally obtained when P. ovale wallikeri primers were used. Although P. ovale is not frequently found in Colombia, there is a clear need to include both P. ovale curtisi and P. ovale wallikeri in the molecular diagnostic strategy. Such need stems primarily from their extended latency period, which affects travelers, the increasing number of African migrants, and the importance of accurately mapping the distribution of Plasmodium species in Colombia.

Differential gut microbiome in spondyloarthritis patients associated to Blastocystis colonization.

The role of Blastocystis in intestinal health is an open controversy, and little is known about the potential effect of this microorganism in autoinflammatory diseases such as spondyloarthritis (SpA). Here, we analyzed the gut microbiome of 36 SpA patients and 13 control individuals and demonstrated that the richness, diversity, and taxonomic composition between these two groups are different. We also showed that colonization by Blastocystis in control individuals increases the richness and diversity of the intestinal microbiome, whereas in SpA patients, it does not seem to have any impact. This may reflect a potential role of Blastocystis in sculpting the gut microbiome architecture in control individuals, whereas in subjects with SpA, the modulation of the microbiome may be governed by disease-dependent factors that cannot be overcome by Blastocystis. Regarding taxonomic characterization, SpA patients colonized by Blastocystis showed significant increases in the phylum Pseudomonadota, class Gammaproteobacteria, family Succinivibrionaceae, and genus Succinivibrio. Simultaneously, there were significant increases in the class Bacilli, order Lactobacillales, families Lactobacillaceae and Clostridiaceae, and genera Lactobacillus and Clostridium in non-colonized SpA patients. On the other hand, PICRUSt analysis in Blastocystis-positive SpA patients showed elevations in pathways that may enhance antioxidant capacities and alleviate intestinal inflammation, while Blastocystis-negative SpA patients showed significant changes in pathways that promote cell division/proliferation and can lead to larger changes in the gut microbiome. Our analyses lead us to believe that these changes in the gut microbiome of SpA patients may trigger protective mechanisms as an initial response to inflammation in an attempt to restore balance in the intestinal environment.

Exploring Blastocystis genetic diversity in rural schoolchildren from Colombia using next-generation amplicon sequencing reveals significant associations between contact with animals and infection risk.

Blastocystis is a common intestinal protist with a global distribution in humans and many other animals. Yet, the status of Blastocystis as a pathogen, the risk factors associated with its transmission, and its zoonotic potential remain ill-defined. Here, we explored subtype (ST) diversity and potential risk factors for Blastocystis infection in 98 children from Apulo, Colombia. Samples were screened for Blastocystis via PCR, and ST identification was performed through next-generation amplicon sequencing (NGS). Associations between the presence of Blastocystis and individual STs and sociodemographic variables were assessed via logistic regression analyses. Seventy-one samples (72.4%) were Blastocystis-positive, and NGS revealed the presence of five STs (ST1-ST5). ST1, ST2, and ST3 were common and observed in nearly equal proportions (~ 40%), while samples with ST4 (1.4%) and ST5 (5.6%) were comparatively rare. The presence of mixed STs in the same sample was also common (28.2%). Comparisons among children within the same household identified that shared ST profiles were common, but diversity within family units was also observed. Logistic regression analyses returned significant associations between the presence of Blastocystis, individual subtypes, or mixed subtypes for several variables. Intriguingly, the presence of animals was one of the most common significant associations. Taken together, these data represent an important step forward in understanding both the potential routes and risk factors that may influence Blastocystis transmission and will be useful in shaping future studies which seek to clarify the relationships between STs, pathogenicity, and zoonotic transmission.

Seguridad de las drogas biológicas y sintéticas dirigidas utilizadas en pacientes con enfermedades reumáticas inmunomediadas. Datos del registro BIOBADASAR 3.0 / Safety of biological and targeted synthetic drugs in patients with immune-mediated rheumatic diseases. Data from the BIOBADASAR 3.0 registry

Introducción: conocer la seguridad de las drogas actualmente disponibles para el tratamiento de las enfermedades reumáticas es muy importante al momento de tomar decisiones terapéuticas objetivas e individualizadas en la consulta médica diaria. Asimismo, datos de la vida real amplían el conocimiento revelado por los ensayos clínicos. Objetivos: describir los eventos adversos (EA) reportados, estimar su frecuencia e identificar los factores relacionados con su desarrollo. Materiales y métodos: se utilizaron datos BIOBADASAR, un registro voluntario y prospectivo de seguimiento de EA de tratamientos biológicos y sintéticos dirigidos en pacientes con enfermedades reumáticas inmunomediadas. Los pacientes son seguidos hasta la muerte, pérdida de seguimiento o retiro del consentimiento informado. Para este análisis se extrajeron datos recopilados hasta el 31 de enero de 2023. Resultados: se incluyó un total de 6253 pacientes, los cuales aportaron 9533 ciclos de tratamiento, incluyendo 3647 (38,3%) ciclos sin drogas modificadoras de la enfermedad biológicas y sintéticas dirigidas (DME-b/sd) y 5886 (61,7%) con DME-b/sd. Dentro de estos últimos, los más utilizados fueron los inhibidores de TNF y abatacept. Se reportaron 5890 EA en un total de 2701 tratamientos (844 y 1857 sin y con DME-b/sd, respectivamente), con una incidencia de 53,9 eventos cada 1000 pacientes/año (IC 95% 51,9-55,9). La misma fue mayor en los ciclos con DME-b/sd (71,1 eventos cada 1000 pacientes/año, IC 95% 70,7-77,5 versus 33,7, IC 95% 31,5-36,1; p<0,001). Las infecciones, particularmente las de la vía aérea superior, fueron los EA más frecuentes en ambos grupos. El 10,9% fue serio y el 1,1% provocó la muerte del paciente. El 18,7% de los ciclos con DME-b/sd fue discontinuado a causa de un EA significativamente mayor a lo reportado en el otro grupo (11,5%; p<0,001). En el análisis ajustado, las DME-b/sd se asociaron a mayor riesgo de presentar al menos un EA (HR 1,82, IC 95% 1,64-1,96). De igual manera, la mayor edad, el mayor tiempo de evolución, el antecedente de enfermedad pulmonar obstructiva crónica, el diagnóstico de lupus eritematoso sistémico y el uso de corticoides se asociaron a mayor riesgo de EA. Conclusiones: la incidencia de EA fue significativamente superior durante los ciclos de tratamientos que incluían DME-b/sd.

Introduction: knowing the efficacy and safety of the drugs currently available for the treatment of rheumatic diseases is very important when making objective and individualized therapeutic decisions in daily medical consultation. Likewise, real-life data extends the knowledge revealed by clinical trials. Objectives: to describe the reported adverse events (AEs), estimate their frequency and identify factors associated to them. Materials and methods: BIOBADASAR data were used, which is a voluntary, prospective follow-up registry of AEs of biological and synthetic treatments in patients with immune-mediated rheumatic diseases. Patients are followed until death, loss of followup, or withdrawal of informed consent. To carry out this analysis, the data collected up to January 31, 2023 was extracted. Results: a total of 6253 patients were included, who contributed with 9533 treatment periods, including 3647 (38.3%) periods without b/ts-DMARDs and 5886 (61.7%) with b/ts-DMARDs. Among the latter, the most used were TNF inhibitors and abatacept. A total of 5890 AEs were reported in a total of 2701 treatments (844 and 1857 without and with b/ts-DMARDs, respectively), with an incidence of 53.9 events per 1000 patients/ year (95% CI 51.9-55.9). It was higher during the periods with b/ts-DMARDs (71.1 events per 1000 patients/year, 95% CI 70.7-77.5 vs 33.7, 95% CI 31.5-36.1, p<0.001). Infections, particularly those of the upper respiratory tract, were the most frequent AEs in both groups. 10.9% were severe and 1.1% were associated with the death of the patient. 18.7% of the periods with b/ts-DMARDs were discontinued due to an AE, significantly higher than that reported in the other group (11.5%; p<0.001). In the adjusted analysis, b/ts-DMARDs were associated with a higher risk of presenting at least one AE (HR 1.82, 95% CI 1.64-1.96). Similarly, older age, longer evolution time, history of chronic obstructive pulmonary disease, diagnosis of systemic lupus erythematosus, and use of corticosteroids were associated with a higher risk of AE. Conclusions: the incidence of AEs was significantly higher during those treatment periods that included DME-b/sd.

Decreased fecal calprotectin levels in Spondyloarthritis patients colonized by Blastocystis spp.

Spondyloarthritis (SpA) is a group of chronic inflammatory systemic diseases mainly characterized by inflammation in the spine and/or peripheral joints. Although a link between SpA-pathogenesis, intestinal inflammation and gut dysbiosis has been proposed, studies have been focused on bacteria-host interactions and very little has been reported regarding intestinal parasites. Here, intestinal parasitic infection of 51 SpA-patients were evaluated and compared to healthy control individuals. No significant differences in the frequency of any parasite between SpA-patients and control individuals were found. Significantly higher levels of fecal calprotectin (FCP) were found in the SpA-patients compared to the control individuals. However, FCP levels were the same when comparing SpA-patients and control individuals, both colonized by Blastocystis spp. On the other hand, when comparing Blastocystis spp. colonized and Blastocystis spp. free SpA-patients, FCP levels were significantly higher in those Blastocystis spp. free. Without ignoring the small sample size as a study limitation, the results showed that in the SpA-patients colonized by Blastocystis spp., the FCP levels were significantly lower than those in the Blastocystis spp. free group and comparable to those in the control group. These findings seem to suggest a relationship between Blastocystis spp. and intestinal inflammation in SpA-patients, but studies intended to explore that interaction specifically should be designed.

Frequency and distribution of Blastocystis sp. subtypes in patients with spondyloarthritis in Bogotá, Colombia.

Although Blastocystis sp. is one of the most prevalent intestinal parasites worldwide, its role as a pathogen remains unclear. The use of molecular techniques to assess the genetic heterogeneity of Blastocystis sp. has become important to understand its function in some intestinal pathologies and if it is a key component of intestinal microbiota. Spondyloarthritis is a group of immune-mediated autoinflammatory diseases in which microbial dysbiosis in the gut (including parasites, bacteria and fungi) and intestinal inflammation are common features apparently associated with the pathophysiology of these disorders. This study included 74 patients diagnosed with spondyloarthritis and 57 systemically healthy individuals (included as controls), who were screened for intestinal parasites. Blastocystis sp. was detected in 68% and 73% of the patients with spondyloarthritis and controls, respectively. In faecal samples positive for Blastocystis sp., an 18S rRNA gene fragment of Blastocystis sp. was amplified and sequenced to identify their genetic sub-types. Patients with spondyloarthritis showed similar frequencies of ST1, ST2 and ST3 subtypes of Blastocystis sp. (30% each). The same subtypes were observed in controls, wherein almost 60% of the samples showed ST3. In addition, ST6 was found only in one sample from each group. ST1 subtype showed the greatest genetic variability. Although the same subtypes were detected in both patients with spondyloarthritis and controls, subtype prevalence studies conducted in Colombia indicate an association between ST3 and individuals with irritable bowel syndrome. This opens an interesting research avenue to further study of the epidemiology of Blastocystis sp. and its possible relationship with intestinal conditions in immunocompromised patients.

Sobrevida, eficacia y seguridad de Golimumab en pacientes con Artritis Reumatoidea y Espondiloartritis: Datos de una cohorte argentina / Survival, efficacy and safety of Golimumab in patients with Rheumatoid Arthritis and Spondyloarthritis: Data from an Argentine cohort

Objetivos: Golimumab ha sido aprobado para el tratamiento de pacientes con artritis reumatoidea (AR), artritis psoriásica (APs) y espondiloartritis axial. Sin embargo, los datos provenientes de nuestra región son escasos. El objetivo de este estudio fue evaluar la eficacia, seguridad y sobrevida acumulada de golimumab en pacientes de la vida real con AR, APs y espondilitis anquilosante (EA) de diferentes centros de Argentina. Material y métodos: Se llevó a cabo un estudio longitudinal, en el que se incluyeron pacientes consecutivos mayores de 18 años con diagnóstico de AR (criterios ACR/EULAR 2010), APs (criterios CASPAR) y Espax (criterios ASAS 2009), que hayan iniciado tratamiento con golimumab de acuerdo a la indicación médica. Se obtuvieron los datos por revisión de historias clínicas. Se consignaron características sociodemográficas, clínicas, comorbilidades y tratamientos previos. Con respecto al golimumab, se registraron fecha de inicio, vía de administración y tratamientos concomitantes. Se determinó la actividad de la enfermedad mediante DAS28 en el caso de la AR, por DAPSA y MDA para APs y por BASDAI en el caso de Espax. Se consignó la presencia de eventos adversos (EA). En el caso de suspensión del tratamiento, se identificaron la fecha y motivo del mismo. Los pacientes fueron seguidos hasta la suspensión del golimumab, pérdida de seguimiento, muerte, o finalización del estudio (30 de noviembre de 2020). Resultados: Se incluyeron 182 pacientes, 116 con diagnóstico de AR, 30 con APs y 36 con Espax. La mayoría de ellos (70.9%) eran mujeres con una edad mediana (m) de 55 años (RIC 43.8-64) y una duración de la enfermedad m de 7 años (RIC 4-12.7) al inicio del tratamiento. El 34.6% de los mismos habían recibido al menos una droga modificadora de la enfermedad (DME) biológica (-b) o sintética dirigida (-sd) previamente. El seguimiento total fue de 318.1 pacientes/año. El tratamiento con golimumab mostró mejoría clínica en los tres grupos de pacientes. La incidencia de eventos adversos fue de 6.6 por 100 pacientes/año, siendo las infecciones las más frecuentes. Durante el seguimiento, 50 pacientes (27.5%) suspendieron golimumab, la causa más frecuente fue el fracaso del tratamiento (68%), seguida de la falta de cobertura (16%) y el desarrollo de eventos adversos (10%). La persistencia de golimumab fue del 76% y 68% a los 12 y 24 meses, respectivamente. Se registró una sobrevida de 50.2 meses (IC 95% 44.4-55.9). Los pacientes que habían recibido tratamiento previo con DME-b y/o -sd mostraron una menor sobrevida (HR 2.4, IC 95% 1.3-4.4). Conclusiones: El tratamiento con golimumab en pacientes de la vida real en Argentina ha demostrado una buena eficacia y seguridad. La sobrevida del fármaco fue de más de 4 años y casi el 80% seguía usando golimumab después de un año. El tratamiento previo con otros DME-b o -sd se asoció con una menor sobrevida al tratamiento.

Objectives: Golimumab is approved for patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis. However, data from our region are scarce. The aim of this study was to evaluate the efficacy, safety, and cumulative survival of golimumab in real-life patients with RA, PsA and axial spondyloarthritis (axSpa) from different rheumatology centers in Argentina. Material and methods: We performed a longitudinal study of consecutive adults with RA (ACR/EULAR 2010 criteria), PsA (CASPAR criteria) and axSpa (ASAS 2009 criteria), who have started treatment with golimumab according to medical indication. Data was obtained by review of medical records. Sociodemographic and clinical data, musculoskeletal manifestations, comorbidities and previous treatments were recorded. In reference to golimumab treatment, start date, route of administration and concomitant treatments were identified. Disease activity was assessed using DAS28 for RA patients, DAPSA and MDA for PsA and BASDAI for axSpa. The presence of adverse events was recorded. If golimumab was stopped, date and cause was documented. Patients were followed up until golimumab discontinuation, loss of follow-up, death, or study completion (November 30, 2020). Results: In total 182 patients were included, 116 with a diagnosis of RA, 30 with PsA and 36 with axSpa. Most of them (70.9%) were female with a median (m) age of 55 years (IQR 43.8-64) and m disease duration of 7 years (IQR 4-12.7) at treatment initiation. Al least one prior biological (-b) and/or targeted synthetic (-ts) disease modifying antirheumatic drug (DMARD) was received by 63 patients (34.6%). Total follow-up was 318.1 patients/year. Golimumab treatment showed clinical improvement in all three groups of patients. The incidence of AE was 6.6 per 100 patients/year, being infections the most frequents ones. During follow-up, 50 patients (27.5%) discontinued golimumab, the most frequent cause was treatment failure (68%), followed by lack of health insurance (16%) and adverse events (10%). Golimumab persistence was 76% and 68% at 12 and 24 months, respectively. Treatment survival was 50.2 months (95% CI 44.4-55.9). Patients who had received prior treatment with b- or ts-DMARDs showed lower survival (HR 2.41, 95% CI 1.3-4.4). Conclusions: Golimumab treatment in real life patients in Argentina has shown good efficacy and safety. Drug survival was over 4 years and almost 80% were still using golimumab after one year. Prior treatment with other b- or ts-DMARDs was associated with lower treatment survival.

Assembly and release of Dengue virus: Role of Alix protein / Ensamblaje y liberación del virus dengue: controversia sobre la participación de la proteína alix

RESUMEN Algunos virus envueltos usurpan la maquinaria celular ESCRT (complejo de clasificación endosomal requerido para el transporte) para llevar a cabo funciones como la transcripción, la traducción, el ensamblaje y la liberación de partículas virales desde las células huésped. Aunque esta estrategia ha sido estudiada principalmente en retrovirus, son varios los virus envueltos que la usan. El objetivo del trabajo fue explorar la participación de una proteína accesoria de ESCRT, la proteína Alix, en la transcripción, traducción, ensamblaje y liberación del virus dengue (DENV), así como su interacción con la proteína viral NS3. Células A549 infectadas con DENV2 fueron tratadas con pequeños ARN de interferencia (siRNA) para disminuir la expresión ("knock-down") de la proteína Alix. Simultáneamente, se obtuvo una línea A549 que expresaba una proteína NS3 recombinante y sobre este sistema se hicieron ensayos de inmunoprecipitación y "pull-down" para detectar interacción entre NS3 y Alix. Los resultados mostraron que el "knock-down" de Alix no tuvo efecto notable en la transcripción o la traducción viral, pero sí en el ensamblaje y la liberación de DENV2, mientras que los ensayos de "pull-down" revelaron la interacción entre NS3 y Alix. La participación de Alix en la producción de DENV2 y su interacción con NS3 constituyen un potencial blanco para el diseño de estrategias dirigidas a controlar la propagación de DENV.

ABSTRACT Since the finding that HIV recruits cellular ESCRT (endosomal sorting complexes required for transport) machinery to accomplish viral budding, this strategy has emerged as an escape route for enveloped viruses also. The work aimed to explore the participation of the cellular protein Alix (a human protein that acts as an adapter in the ESCRT pathway) on the transcription, protein expression, assembly and release of Dengue virus (DENV), and explore for its potential interaction with the viral protein NS3. To this purpose, A549 cells were infected with DENV2 and treated with small interfering RNAs (siRNA) to generate an Alix stable knockdown cells line. Also, an A549 cells line expressing a histidine-tagged NS3 protein was obtained. Both cells lines were used in immunoprecipitation and pull-down assays to assess the interaction between NS3 and Alix. The results showed that Alix knockdown had no effect on viral transcription or viral protein expression but influenced the assembly and release of DENV2 negatively. Finally, pull-down assays revealed the interaction between NS3 and Alix. The finding of an Alix participation in the production of DENV2 and its interaction with NS3 provides a potential target for the design of control/inhibition strategies against DENV spread.

Does Resolution 8430 of 1993 respond to the current needs of ethics in health research with human beings in Colombia? / ¿Responde la Resolución 8430 de 1993 a las necesidades actuales de la ética de la investigación en salud con seres humanos en Colombia?

Verifying the compliance with the ethical principles of health research legitimizes its exercise in the eyes of the society and allows for the resolution of ethical dilemmas that emerge from new research interests and methods. Resolution 8430 of 1993 is one of the main ethical guidelines governing health research on human beings in Colombia. Considering that the resolution has not been revised or updated since its promulgation it becomes necessary to evaluate its current validity and adequacy to address the potential ethical dilemmas in the existing country's health research. Some gaps, contradictions, and aspects that require a deep review are detailed in this paper from a wide conception of health research areas and methods. After discussing the main weaknesses and inaccuracies, some alternatives are proposed to adjust the resolution to the present needs in health research with human beings.

La verificación del cumplimiento de los principios éticos en la investigación en salud legitima su ejercicio ante la sociedad y posibilita la resolución de dilemas éticos frente a nuevos intereses y métodos de investigación. En Colombia, la Resolución 8430 de 1993 es una de las principales pautas éticas que regulan la investigación en salud. Dado que no ha sido revisada ni actualizada desde su adopción, se hace necesario valorar su vigencia y suficiencia para abordar los potenciales dilemas éticos que se plantean actualmente en la investigación en salud en el país. En este contexto, se detallan algunos vacíos y contradicciones, así como aspectos que requieren de una revisión profunda, a partir de una concepción amplia de las áreas y los métodos de investigación en salud. Tras discutir las principales falencias e imprecisiones, se proponen alternativas para que la Resolución responda a las necesidades actuales del país frente a la ética en investigación en salud con seres humanos.

¿Responde la Resolución 8430 de 1993 a las necesidades actuales de la ética de la investigación en salud con seres humanos en Colombia? / Does Resolution 8430 of 1993 respond to the current needs of ethics in health research with human beings in Colombia?

Resumen La verificación del cumplimiento de los principios éticos en la investigación en salud legitima su ejercicio ante la sociedad y posibilita la resolución de dilemas éticos frente a nuevos intereses y métodos de investigación. En Colombia, la Resolución 8430 de 1993 es una de las principales pautas éticas que regulan la investigación en salud. Dado que no ha sido revisada ni actualizada desde su adopción, se hace necesario valorar su vigencia y suficiencia para abordar los potenciales dilemas éticos que se plantean actualmente en la investigación en salud en el país. En este contexto, se detallan algunos vacíos y contradicciones, así como aspectos que requieren de una revisión profunda, a partir de una concepción amplia de las áreas y los métodos de investigación en salud. Tras discutir las principales falencias e imprecisiones, se proponen alternativas para que la Resolución responda a las necesidades actuales del país frente a la ética en investigación en salud con seres humanos.

Abstract Verifying the compliance with the ethical principles of health research legitimizes its exercise in the eyes of the society and allows for the resolution of ethical dilemmas that emerge from new research interests and methods. Resolution 8430 of 1993 is one of the main ethical guidelines governing health research on human beings in Colombia. Considering that the resolution has not been revised or updated since its promulgation it becomes necessary to evaluate its current validity and adequacy to address the potential ethical dilemmas in the existing country's health research. Some gaps, contradictions, and aspects that require a deep review are detailed in this paper from a wide conception of health research areas and methods. After discussing the main weaknesses and inaccuracies, some alternatives are proposed to adjust the resolution to the present needs in health research with human beings.

Intestinal parasitic infections and associated factors in children of three rural schools in Colombia. A cross-sectional study.

Rural children are one of the populations that are most vulnerable to gastrointestinal parasite infections. Such diseases decrease the quality of life and result in growth and cognitive delays in the long term. This cross-sectional study was conducted to determine the frequency of intestinal parasite infections among rural schoolchildren in the municipality of Apulo, Colombia. A total of 97 stool samples from children aged between 5 and 15 years were collected and examined via direct light microscopy. Microscopic examination was repeated with sediments obtained using a fecal parasite concentrator, and the Kato-Katz test was performed. Frequency of intestinal parasite infection was 100%. Endolimax nana (77.35%), Blastocystis sp. (71.1%), Giardia intestinalis (39.1%), Entamoeba coli (25.7%), and the Entamoeba histolytica/dispar/moshkovskii complex (9.2%) were the most prevalent protozoa. Trichuris trichiura was the most prevalent helminth (12.3%), followed by Enterobius vermicularis (6.15%) and Ascaris lumbricoides (5.1%). Among the analyzed associated factors, consumption of untreated water increased the risk of acquiring pathogenic intestinal parasites. Finally, because G. intestinalis was the most prevalent pathogenic protozoan, molecular analysis was conducted to establish genetic assemblages and subassemblages of Giardia through sequence-based genotyping of the glutamate dehydrogenase, triose phosphate isomerase, and beta-giardin genes. A total of 14 G. intestinalis-positive samples were genotyped, which revealed the presence of subassemblages AI (n = 1), AII (n = 7), BIII (n = 2), BIV (n = 2), and BIII/BIV (n = 1) as well as a mixed subassemblage AII + BIII (n = 1). Our results indicate that gastrointestinal parasite infections in the tested population were mainly caused by suboptimal water quality. Moreover, molecular typing of G. intestinalis suggested contamination of water by animal- and human-derived cysts.

Systematic Comparison of Strategies to Achieve Soluble Expression of Plasmodium falciparum Recombinant Proteins in E. coli.

Constructs containing partial coding sequences of myosin A, myosin B, and glideosome-associated protein (50 kDa) of Plasmodium falciparum were used to challenge several strategies designed in order to improve the production and solubility of recombinant proteins in Escherichia coli. Assays were carried out inducing expression in a late log phase culture, optimizing the inductor concentration, reducing the growth temperature for induced cultures, and supplementing additives in the lysis buffer. In addition, recombinant proteins were expressed as fusion proteins with three different tags (6His, GST, and MBP) in four different E. coli strains. We found that the only condition that consistently produced soluble proteins was the use of MBP as a fusion tag, which became a valuable tool for detecting the proteins used in this study and did not caused any interference in protein-protein interaction assays (Far Western Blot). Besides, we found that BL21-pG-KJE8 strain did not improve the solubility of any of the recombinant protein produced, while the BL21-CodonPlus(DE3)-RIL strain improved the expression of some of them independent of the rare codon content. Proteins with rare codons occurring at high frequencies (¼ 10%) were expressed efficiently in strains that do not supplement tRNAs for these triplets.

[Polyclonal antibodies against recombinant dengue virus NS3 protein].

INTRODUCTION: Dengue is a disease caused by one of four serotypes of the dengue virus (DENV) and is endemic in approximately 130 countries. The incidence of dengue has increased dramatically in recent decades, as well as the frequency and magnitude of outbreaks. Despite all efforts, there are no prophylactic or therapeutic treatments for the disease. Accordingly, research on the processes governing the DENV infection cycle is essential to develop vaccines or antiviral therapies. One of themost attractive DENV molecules to investigate is nonstructural protein 3 (NS3), which is essential for viral replication and a major immune target for infection. OBJECTIVE: To produce antibodies to support future studies on NS3 and its cellular interactions with other proteins. MATERIALS AND METHODS: Two recombinant proteins of the helicase domain of DENV NS3 serotype 2 were expressed, and used to immunize mice and produce polyclonal antibodies. RESULTS: The antibodies produced were useful in Western blot and immunofluorescence tests. We report an NS3 antibody that immunoprecipitates the viral protein and detects it in Western blot with no need to over-express it or use cell extracts with metabolic radiolabeling. CONCLUSION: The recombinant proteins expressed and the antibodies produced constitute valuable tools for studying DENV infectious processes involving NS3 and for evaluating tests designed to interfere with its functions.

Myosin B of Plasmodium falciparum (PfMyoB): in silico prediction of its three-dimensional structure and its possible interaction with MTIP.

The mobility and invasion strategy of Plasmodium falciparum is governed by a protein complex known as the glideosome, which contains an actin-myosin motor. It has been shown that myosin A of the parasite (PfMyoA) is the myosin of the glideosome, and the interaction of PfMyoA with myosin tail domain interacting protein (MTIP) determines its correct location and its ability to function in the complex. Because PfMyoA and myosin B of P. falciparum (PfMyoB) share high sequence identity, are both small proteins without a tail domain, belong to the class XIV myosins, and are expressed in late schizonts and merozoites, we suspect that these myosins may have similar or redundant functions. Therefore, this work examined the structural similarity between PfMyoA and PfMyoB and performed a molecular docking between PfMyoB and MTIP. Three-dimensional (3D) models obtained for PfMyoA and PfMyoB achieved high scores in the structural validation programs used, and their superimposition revealed high structural similarity, supporting the hypothesis of possible similar functions for these two proteins. The 3D interaction models obtained and energy values found suggested that interaction between PfMyoB and MTIP is possible. Given the apparent abundance of PfMyoA relative to PfMyoB in the parasite, we believe that the interaction between PfMyoB and MTIP would only be detectable in specific cellular environments because under normal circumstances, it would be masked by the interaction between PfMyoA and MTIP.

Anticuerpos policlonales contra la proteína recombinante NS3 del virus del dengue / Polyclonal antibodies against recombinant dengue virus NS3 protein

Resumen Introducción: El dengue es una enfermedad causada por uno de los cuatro serotipos del virus del dengue (DENV) y es endémica en, aproximadamente, 130 países. Su incidencia ha aumentado notablemente en las últimas décadas, así como la frecuencia y la magnitud de los brotes. A pesar de los esfuerzos, no existen tratamientos profilácticos ni terapéuticos contra la enfermedad y, en ese contexto, el estudio de los procesos que gobiernan el ciclo de infección del DENV es esencial para desarrollar vacunas o terapias antivirales. Una de las moléculas del DENV más prometedoras es la proteína no estructural 3 (NS3), la cual es indispensable para la replicación viral y es uno de los principales blancos inmunológicos durante la infección. Objetivo: Producir anticuerpos policlonales para contribuir a los futuros estudios sobre las interacciones entre la proteína NS3 y otras proteínas celulares. Materiales y métodos: Se expresaron dos proteínas recombinantes del dominio helicasa de NS3 del DENV de serotipo 2, las cuales se emplearon para inmunizar ratas y producir anticuerpos policlonales. Resultados: Los anticuerpos producidos fueron útiles en ensayos de Western blot e inmunofluorescencia y se reportó por primera vez un anticuerpo policlonal anti-NS3 que permitió la inmunoprecipitación de la proteína viral y la detecta con Western blot sin necesidad de inducir sobreexpresión de NS3 o de usar extractos de células marcados metabólicamente con radioisótopos. Conclusión: Las proteínas recombinantes expresadas y los anticuerpos producidos constituyen herramientas valiosas para estudiar procesos infecciosos del DENV que involucren a la proteína NS3 y evaluar pruebas dirigidas a interferir las funciones de esta proteína.

Abstract Introduction: Dengue is a disease caused by one of four serotypes of the dengue virus (DENV) and is endemic in approximately 130 countries. The incidence of dengue has increased dramatically in recent decades, as well as the frequency and magnitude of outbreaks. Despite all efforts, there are no prophylactic or therapeutic treatments for the disease. Accordingly, research on the processes governing the DENV infection cycle is essential to develop vaccines or antiviral therapies. One of the most attractive DENV molecules to investigate is nonstructural protein 3 (NS3), which is essential for viral replication and a major immune target for infection. Objective: To produce antibodies to support future studies on NS3 and its cellular interactions with other proteins. Materials and methods: Two recombinant proteins of the helicase domain of DENV NS3 serotype 2 were expressed, and used to immunize mice and produce polyclonal antibodies. Results: The antibodies produced were useful in Western blot and immunofluorescence tests. We report an NS3 antibody that immunoprecipitates the viral protein and detects it in Western blot with no need to over-express it or use cell extracts with metabolic radiolabeling.

Catheter meaning for the adolescents in dialysis / Significado del catéter para los(as) adolescentes en diálisis

Goal: Terminal renal failure affects all the person’s life dimensions. The impact of this illness during adolescence is quite dramatic because the adolescent must live with the illness demands and the demands from this crucial developmental stage. Knowledge regarding the impact of the dialysis catheter on the adolescent’s life is spare. Methodology: A phenomenological study was carried out with 8 female and male adolescents that were in dialysis. Findings: The adolescents had to learn to live with the dialysis catheter in their body. The catheter became an obstacle to achieve their identity and deteriorated their physical appearance and peer relationships.

Objetivo: La insuficiencia renal terminal afecta todas las dimensiones de la vida de las personas. El impacto de esta enfermedad durante la adolescencia es más dramático debido a que el(a) adolescente debe además de superar las demandas de esta etapa de la vida, vivir según las demandas de la enfermedad. El conocimiento sobre el impacto del catéter para la diálisis en la vida de los (as) adolescente es escaso. Metodología: Se realizó un estudio fenomenológico con 8 jóvenes de ambos sexos que estaban en diálisis. Resultados: Los(as) jóvenes tuvieron que aprender a vivir con el catéter en su cuerpo. El catéter les generó deterioro de la apariencia física y de las relaciones con los pares, además se constituyó en un obstáculo para lograr la identidad.

Caracterización molecular de los genes histona H2A y ARNsno-Cl de Trypanosoma rangeli: aplicación en pruebas diagnósticas / Molecular characterization of histone H2A and snoRNA-Cl genes of Trypanosoma rangeli: application in diagnostic tests

La aplicación de la reacción en cadena de la polimerasa (PCR) para detectar e identificar Trypanosoma rangeli y Trypanosoma rangeli presenta a menudo dificultades de interpretación. Así, algunas pruebas generan la amplificación de bandas similares provenientes de uno de los dos parásitos, fragmentos polimórficos de un mismo parásito, o la prevalencia en la detección de T. cruzi en infecciones mixtas. En este estudio se presentan y analizan los trabajos de investigación básica realizados con el objeto de diseñar y estandarizar pruebas de PCR específicas de cada parásito. Los iniciadores TcH2AF/R se diseñaron sobre la base de la región diferencial observada entre las unidades génicas que contienen los genes h2a en estos tripanosomas. Esta pareja de iniciadores amplifican un fragmento de 234 pb específico para T. cruzi (cepas I y II). Los iniciadores TrF/R2 anillan en las regiones intergénicas del fragmento génico de 801 pb codificante para seis transcritos que forman la agrupación ARNsno-Cl en T. rangeli. Estos iniciadores amplifican un fragmento de 620 pb exclusivo de las cepas KP1(-) y KP1(+) de este parásito. La aplicación de estas PCR en vectores infectados y en pacientes con enfermedad de Chagas muestra que ambas pruebas constituyen herramientas útiles para el diagnóstico y la identificación diferencial de estos tripanosomátidos.

The application of polymerase chain reaction (PCR) to detect Trypanosoma rangeli and Trypanosoma rangeli often presents interpretation challenges. For example, some tests yield the amplification of similar bands from either parasite, polymorphic fragments of the same parasite, or present deviation towards T. cruzi in mixed infections. In this study, the basic researching needed for designing and standardizating specific PCR tests for each parasite species PCR are shown and analyzed. The TcH2AF/R primers were designed on the basis of the differential gene region observed between the histone h2a genic units of these parasites. These primers amplify a specific 234 bp fragment in T. cruzi (T. cruzi I and II strains). The TrF/R2 primers anneal to the intergenic regions of an 801 bp gene fragment encoding for six transcripts that conform the snoRNA-Cl cluster in T. rangeli. These primers amplify a fragment of 620 bp exclusively in KP1(-) and KP1(+) strains of the parasite. The application of these PCR tests in infected vectors and in chagasic patients show that both tests constitute useful tools for the diagnosis and differential identification of these Trypanosomatids. Key words: histone, RNA small nucleolar (snoRNA), polymerase chain reaction (PCR), Trypanosoma.

Rate and causes of infliximab discontinuation in patients with rheumatoid arthritis in a private clinical practice.

OBJECTIVES: To describe the rate of infliximab discontinuation and the causes of this event in a population of rheumatoid arthritis patients. PATIENTS AND METHODS: Rheumatoid arthritis patients from an out-patient private center treated with infliximab (at least 2 consecutive doses) were retrospectively studied. The infliximab discontinuation rate was examined by the Kaplan-Meier survival method. Variables associated with infliximab discontinuation were analyzed by univariable and multivariable Cox proportional hazards regression analyses. RESULTS: Seventy-seven patients treated with infliximab between August 2000 and December 2006 were identified; of them, 33 (43%) discontinued this drug. The cumulative discontinuation rate was of 23%, 35%, and 43% at 12, 24, and 36 months, respectively. Causes of discontinuation were drug-related adverse reactions (41%), financial constraints (15%), lack of efficacy (12%), and others (32%). Variables independently associated with infliximab discontinuation were the number of tender joints on an average during infliximab treatment [hazard ratio (HR) = 1.17, 95% confidence interval (CI) 1.05-1.31; P = 0.005] and the occurrence of any adverse reaction attributed to infliximab (HR = 2.86, 95% CI 1.37-7.19; P = 0.026), whereas having full pharmacy coverage for infliximab (HR = 0.32, 95% CI 0.13-0.79, P = 0.014) was protective. CONCLUSION: Forty-three percent of patients discontinued infliximab at 3 years; most of them because of adverse reactions and financial constraints. Rheumatologists should be aware that those patients with more active disease were also at higher risk of discontinuing infliximab.