Early-life external exposome in children 2-5 years old in Colombia.

Exposome studies are advancing in high-income countries to understand how multiple environmental exposures impact health. However, there is a significant research gap in low- and middle-income and tropical countries. We aimed to describe the spatiotemporal variation of the external exposome, its correlation structure between and within exposure groups, and its dimensionality. A one-year follow-up cohort study of 506 children under 5 in two cities in Colombia was conducted to evaluate asthma, acute respiratory infections, and DNA damage. We examined 48 environmental exposures during pregnancy and 168 during childhood in eight exposure groups, including atmospheric pollutants, natural spaces, meteorology, built environment, traffic, indoor exposure, and socioeconomic capital. The exposome was estimated using geographic information systems, remote sensing, spatiotemporal modeling, and questionnaires. The median age of children at study entry was 3.7 years (interquartile range: 2.9-4.3). Air pollution and natural spaces exposure decreased from pregnancy to childhood, while socioeconomic capital increased. The highest median correlations within exposure groups were observed in meteorology (r = 0.85), traffic (r = 0.83), and atmospheric pollutants (r = 0.64). Important correlations between variables from different exposure groups were found, such as atmospheric pollutants and meteorology (r = 0.76), natural spaces (r = -0.34), and the built environment (r = 0.53). Twenty principal components explained 70%, and 57 explained 95% of the total variance in the childhood exposome. Our findings show that there is an important spatiotemporal variation in the exposome of children under 5. This is the first characterization of the external exposome in urban areas of Latin America and highlights its complexity, but also the need to better characterize and understand the exposome in order to optimize its analysis and applications in local interventions aimed at improving the health conditions and well-being of the child population and contributing to environmental health decision-making.

Cytotoxic Evaluation in HaCaT Cells of the Pa.7 Bacteriophage from Cutibacterium (Propionibacterium) acnes, Free and Encapsulated Within Liposomes.

Introduction: Acne is a multifactorial disease involving the colonization of skin follicles by Cutibacterium (formerly Propionibacterium) acnes. A combination of different retinoid-derived products, antibiotics, and hormonal antiandrogens are used to treat the disease, but these treatments require extended periods, may have secondary effects, are expensive, and not always effective. Owing to antibiotic resistance, the use of bacteriophages has been proposed as an alternative treatment. However, if they are intended for a cosmetic or pharmaceutical use, it is necessary to evaluate the safety of the phages and the preparations containing them. Materials and Methods: In this study, the cytotoxicity of Pa.7 bacteriophage was evaluated in HaCaT cells, along with a liposome suitable for their encapsulation, using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and trypan blue assays. Results: We found that Pa.7 was not cytotoxic for HaCaT cells. Also, 30 mM of liposomes, or below are considered noncytotoxic concentrations. Conclusion: Phages encapsulated in the liposomes presented in this study can be used safely for skin treatments.

Microbially Synthesized Polymer-Metal Nanoparticles Composites as Promising Wound Dressings to Overcome Methicillin-Resistance Staphylococcus aureus Infections.

Antimicrobial resistance has been declared one of the top 10 global public health threats. Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of recurring skin and soft tissue infections in patients with chronic skin conditions such as diabetic foot infections, making the treatment of the ulcers challenging. Wound dressings combined with metal nanoparticles have been suggested to prevent and treat MRSA-infected wounds. However, these particles are commonly synthesized by chemical approaches. In this study, we developed bio-based silver (Bio-AgNPs) and copper oxide nanoparticles (CuONPs) polymer composites using a microbially produced polyester from the Polyhydroxyalkanoates (PHAs) family. Poly(3-hydroxyoctanoate)-co-(3-hydroxyhexanoate) (PHO) was synthesized by Pseudomonas putida and functionalized in-situ with Bio-AgNPs or ex-situ with CuONPs. PHO-CuONPs films did not inhibit MRSA growth, while a reduction of 6.0 log CFU/mL was achieved with PHO-Bio-AgNPs synthesized from silver nitrate (AgNO3) solution at 3.5 mM. Exposure of human fibroblast cells (HFF-1) to the bioactive films did not induce notable cytotoxicity and genotoxicity, as seen by a viability higher than 79% and no significant changes in basal DNA damage. However, exposure to PHO-Bio-AgNPs induced oxidative DNA damage in HFF-1 cells. No hemolytic potential was observed, while platelet aggregation was promoted and desired for wound healing. Here we demonstrate the biosynthesis of polymer-nanoparticle composites and their potential as bioactive films for MRSA treatment.

Characterization of the external exposome and its contribution to the clinical respiratory and early biological effects in children: The PROMESA cohort study protocol.

BACKGROUND: Air pollution contains a mixture of different pollutants from multiple sources. However, the interaction of these pollutants with other environmental exposures, as well as their harmful effects on children under five in tropical countries, is not well known. OBJECTIVE: This study aims to characterize the external exposome (ambient and indoor exposures) and its contribution to clinical respiratory and early biological effects in children. MATERIALS AND METHODS: A cohort study will be conducted on children under five (n = 500) with a one-year follow-up. Enrolled children will be followed monthly (phone call) and at months 6 and 12 (in person) post-enrolment with upper and lower Acute Respiratory Infections (ARI) examinations, asthma development, asthma control, and genotoxic damage. The asthma diagnosis will be pediatric pulmonologist-based and a standardized protocol will be used. Exposure, effect, and susceptibility biomarkers will be measured on buccal cells samples. For environmental exposures PM2.5 will be sampled, and questionnaires, geographic information, dispersion models and Land Use Regression models for PM2.5 and NO2 will be used. Different statistical methods that include Bayesian and machine learning techniques will be used for the ambient and indoor exposures-and outcomes. This study was approved by the ethics committee at Universidad Pontificia Bolivariana. EXPECTED STUDY OUTCOMES/FINDINGS: To estimate i) The toxic effect of particulate matter transcending the approach based on pollutant concentration levels; ii) The risk of developing an upper and lower ARI, based on different exposure windows; iii) A baseline of early biological damage in children under five, and describe its progression after a one-year follow-up; and iv) How physical and chemical PM2.5 characteristics influence toxicity and children's health.

Association of buccal micronucleus cytome assay (BMNCyt) biomarkers with inorganic element concentration and genetic polymorphisms in welders.

Welding fumes are classified as carcinogenic to humans. The aim of the present study was to measure buccal micronucleus cytome assay biomarkers and to evaluate their association with inorganic elements and genetic polymorphisms (XRCC1, OGG1, XRCC3, GSTM1, and GSTT1) in welders (n = 98) and control individuals (n = 100). Higher levels of DNA damage and cell death were observed in the exposed group. Also, a significant correlation between the frequency of micronuclei and Na, Si, Cl, Ti, Cr, Zn and Mg concentrations. The formation of micronuclei, binucleated cells, cell death was associated with polymorphisms in repair pathways. The OGG1Ser326Cys and XRCC3 241Thr/Met genotypes were associated with cell death. Individuals with GSTM1 null genotype had a higher frequency of micronuclei. These results demonstrate that the deleterious effects of exposure to welding fumes are exacerbated by lifestyle habits, and genetic polymorphisms can influence DNA damage and cell death.

Dermatosis en la región mamaria: estudio retrospectivo de 171 pacientes atendidas en el Hospital General Dr. Manuel Gea González / Skin diseases of the breast: A retrospective study of 171 patients at "Dr. Manuel Gea González" General Hospital

Resumen OBJETIVO: Describir las dermatosis de la región mamaria que para su diagnóstico durante la consulta dermatológica ameritaron estudio histopatológico. MATERIALES Y MÉTODOS: Estudio retrospectivo llevado a cabo con base en los expedientes electrónicos de pacientes atendidas en el servicio de Dermatopatología entre 1992 y 2021. Los términos de búsqueda fueron: "mama", "seno", "areola" y "pezón". RESULTADOS: Se reunieron 171 reportes histopatológicos. El diagnóstico clínico de envío más común en mujeres fue la infiltración cutánea por cáncer de mama y en hombres el pezón supernumerario. Las dermatosis más frecuentes pertenecieron al grupo de tumoraciones benignas (78 de 171), seguidas de las dermatosis inflamatorias no infecciosas (48 de 171), en tercer lugar las neoplasias malignas (39 de 171) y 6 de 171 correspondieron a dermatosis inflamatorias infecciosas. CONCLUSIONES: Las enfermedades cutáneas de la mama tienen diversas manifestaciones clínicas que, en ocasiones, ameritan un estudio histopatológico, sobre todo para un diagnóstico oportuno de neoplasias malignas.

Abstract OBJECTIVE: Describe dermatoses of the mammary region that warranted histopathological diagnosis in dermatologic consults. MATERIALS AND METHODS: The Hospital "Dr. Manuel Gea Gonzalez" Dermatopathology Department record database was reviewed in the 1992 to 2021 period, using the search engine terms "breast," "mammary," "nipple," and "areola." Lesions were classified as benign, malignant, infectious and noninfectious inflammatory tumors. RESULTS: 171 histopathological reports were reviewed. There was a female predominance in histopathological studies (153/171). The most frequent clinical diagnosis for referral in female patients was breast cancer with cutaneous infiltration; supernumerary nipple was the most frequent clinical diagnosis for male patients. The most frequent dermatoses belonged to the benign tumor category (78/171), followed by noninfectious inflammatory dermatoses (48/171). Malignant neoplasms were in third place (39/171), and 3.5% of dermatoses were infectious inflammatory dermatoses. CONCLUSIONS: Cutaneous mammary disease has diverse clinical presentations that might occasionally warrant histopathological studies, mainly for the early diagnosis of malignant neoplasms.

Cytokinesis-block micronucleus cytome (CBMN-CYT) assay biomarkers and telomere length analysis in relation to inorganic elements in individuals exposed to welding fumes.

During the welding activities many compounds are released, several of these cause oxidative stress and inflammation and some are considered carcinogenic, in fact the International Agency for Research on Cancer established that welding fumes are carcinogenic to humans. The aim of the present study was to analyze the cytotoxic and genotoxic potential of exposure to welding fumes and to determine concentrations of metals in blood and urine of occupationally exposed workers. We included 98 welders and 100 non-exposed individuals. Our results show significant increase in the frequency of micronuclei (MN), nucleoplasmic bridges (NPB), nuclear buds (NBUD) and necrotic cells (NECR) in cytokinesis-block micronucleus cytome (CBMN-Cyt) assay, as well as in the telomere length (TL) of the exposed individuals with respect to the non-exposed group. In the analysis of the concentrations of inorganic elements using PIXE method, were found higher concentrations of Cr, Fe and Cu in the urine, and Cr, Fe, Mg, Al, S, and Mn in the blood in the exposed group compared to the non-exposed group. A significant correlation was observed between MN and age and between NPB and years of exposure. Additionally, we found a significant correlation for TL in relation to MN, NPB, age and years of exposure in the exposed group. Interestingly, a significant correlation between MN and the increase in the concentration of Mg, S, Fe and Cu in blood samples of the exposed group, and between MN and Cr, Fe, Ni and Cu in urine. Thus, our findings may be associated with oxidative and inflammatory damage processes generated by the components contained in welding fumes, suggesting a high occupational risk in welding workers.

Novel complexes with ONNO tetradentate coumarin schiff-base donor ligands: x-ray structures, DFT calculations, molecular dynamics and potential anticarcinogenic activity.

The synthesis of eight novel Zn(II), Co(II), Cu(II), Ni(II) and Pt(II) complexes (2-9) derived from the ONNO tetradentate coumarin Schiff-Base donor ligands, L1 and the novel L2, was performed. All compounds were characterized by analytical, spectrometry and spectroscopy techniques. Complexes 2-4 were also characterized by DFT calculations and the structures of 5 and 6 were determined by single-crystal X-ray diffraction analysis. A cytotoxicity study was carried out through an MTT assay in the carcinogenic cell line HeLa and the noncarcinogenic cell lines HFF-1 and HaCaT. The results indicated that among all the evaluated compounds, 2 and 6 presented the best anticarcinogenic potential against HeLa cells with an IC50 of 3.5 and 4.1 µM, respectively. In addition, classical molecular dynamics simulations were performed on the synthesized coordination compounds bound to G4 DNA architectures in the scope of shedding light on their inhibition mode and the most conserved interactions that may lead to the biological activity of the compounds.

Antimicrobial and Biocompatible Polycaprolactone and Copper Oxide Nanoparticle Wound Dressings against Methicillin-Resistant Staphylococcus aureus.

One of the major health problems linked to methicillin-resistant Staphylococcus aureus (MRSA) is severe diabetic foot ulcers (DFU), which are associated with hospital-acquired infections, lower limb amputations and emerging resistance to the current antibiotics. As an alternative, this work aims to develop a biodegradable and biocompatible material with antimicrobial capacity to prevent DFU. This was achieved by producing active polymeric films with metallic nanoparticles dispersed through a polycaprolactone (PCL) dressing. First, the antimicrobial activity of copper oxide nanoparticles (CuONPs) was tested by the microdilution method, selecting the lowest concentration that has an inhibitory effect on MRSA. Then, active PCL films were prepared and characterized in terms of their physicochemical properties, antimicrobial performance, cytotoxicity, genotoxicity and hemocompatibility. Active films had chemical and thermal properties like the ones without the antimicrobial agents, which was confirmed through FTIR, Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) analysis. In relation to antimicrobial activity, active PCL films inhibited MRSA growth when treated with CuONPs at a concentration of 0.07% (w/w). After exposure to the active film extracts, human foreskin fibroblast cells (ATCC® SCRC1041™) (HFF-1) exhibited a cell viability average above 80% for all treatments and no DNA damage was found. Finally, PCL films with 0.07% (w/w) CuONPs proved to be hemocompatible, and none of the films evaluated had red blood cell breakage greater than 5%, being within the acceptable limits established by the International Organization for Standardization ISO 10993-4:2002.

Efficacy and Molecular Effects of a Reduced Graphene Oxide/Fe3O4 Nanocomposite in Photothermal Therapy Against Cancer.

PURPOSE: Expanded research on the biomedical applications of graphene has shown promising results, although interactions between cells and graphene are still unclear. The current study aims to dissect the cellular and molecular effects of graphene nanocomposite in photothermal therapy against cancer, and to evaluate its efficacy. METHODS: In this study, a reduced graphene oxide and iron oxide (rGO-Fe3O4) nanocomposite was obtained by chemical synthesis. The nanocomposite was fully characterized by Raman spectroscopy, TEM, VSM and thermal profiling. Cell-nanocomposite interaction was evaluated by confocal microscopy and viability assays on cancer cell line HeLa. The efficacy of the thermal therapy and changes in gene expression of Bcl-2 and Hsp70 was assessed. RESULTS: The resulting rGO-Fe3O4 nanocomposite exhibited superparamagnetic properties and the capacity to increase the surrounding temperature by 18-20°C with respect to the initial temperature. The studies of cell-nanocomposite interaction showed that rGO-Fe3O4 attaches to cell membrane but there is a range of concentration at which the nanomaterial preserves cell viability. Photothermal therapy reduced cell viability to 32.6% and 23.7% with 50 and 100 µg/mL of nanomaterial, respectively. The effect of treatment on the molecular mechanism of cell death demonstrated an overexpression of anti-apoptotic proteins Hsp70 and Bcl-2 as an initial response to the therapy and depending on the aggressiveness of the treatment. CONCLUSION: The results of this study contribute to understanding the interactions between cell and graphene and support its application in photothermal therapy against cancer due to its promising results.

Biomarkers of susceptibility and effect in car painters exposed to organic solvents.

INTRODUCTION: Car painters are routinely exposed to organic solvents classified as carcinogenic and mutagenic substances. OBJECTIVE: To characterize the population susceptibility and evaluate the genotoxic effects of exposure to organic solvents. METHODS: A cross-sectional study comparing a group of car painters exposed to organic solvents with a non-exposed group. CYP2E1 polymorphisms and the presence of micronuclei in lymphocytes were determined. RESULTS: One hundred twenty-two workers participated in the study: 62 who worked in car paint shops and were exposed to solvents, and 60 who were not exposed. There were statistically significant differences between the two groups regarding micronucleated cells and nucleoplasmic bridges frequencies (p= 0.042 and p= 0.046, respectively; exact likelihood ratio). Significant differences were found at the interaction between the CYP2E1 genotype c1c1 and occupational exposure to solvents, with higher frequencies of micronuclei (p= 0.013) and micronucleated cells (p= 0.015). However, when the frequencies of micronuclei, micronucleated cells and nucleoplasmic bridges in the exposure group were compared between the c1c1 and c2c2/c1c2 allele groups of the CYP2E1 polymorphism, statistically significant differences were found. CONCLUSIONS: This study confirms that when workers with CYP2E1 polymorphisms, specifically the c1c1 genotype, are exposed to organic solvents, they are more likely to have somatic cell mutations, a condition associated with increased susceptibility to diseases such as cancer.

INTRODUCCIÓN: Los pintores de vehículos automotores están rutinariamente expuestos a agentes como los solventes orgánicos, capaces de producir efectos mutágenos y carcinógenos. OBJETIVO: Caracterizar la susceptibilidad poblacional y evaluar los efectos genotóxicos debidos a la exposición a solventes orgánicos. MÉTODOS: Estudio de corte transversal que comparó a un grupo de pintores de carros expuestos a solventes orgánicos con un grupo de personas no expuestas. Fueron determinados tanto los polimorfismos de CYP2E1 como la presencia de micronúcleos en linfocitos. RESULTADOS: Participaron 122 personas, 62 trabajadores de talleres de pintura de autos expuestos a solventes y 60 personas no expuestas. Con relación al cuestionario Q 16, 32% de los expuestos refirieron síntomas sugestivos de neurotoxicidad. Las frecuencias de células micronucleadas y de puentes nucleoplásmicos fueron significativamente mayores en los expuestos que en los no expuestos: p= 0.042 y p= 0.046, respectivamente, Razón de verosimilitud exacta). Fueron halladas diferencias significativas en la interacción de CYP2E1 (c1c1) y la exposición ocupacional a solventes, con mayores frecuencias de micronúcleos (p= 0.013) y de células micronucleadas (p= 0.015). CONCLUSIONES: Este estudio reafirma que los trabajadores expuestos a solventes orgánicos con polimorfismos de CYP2E1, específicamente con genotipo c1c1, tienen mayor probabilidad de presentar mutaciones en las células somáticas, condición asociada con una mayor susceptibilidad a enfermedades como el cáncer.

Tridimensional alginate disks of tunable topologies for mammalian cell encapsulation.

We have developed a protocol to produce three-dimensional matrices based on alginate hydrogels for mammalian cell encapsulation. Based on the gelation properties of this polysaccharide, we implemented a calcium ion-based diffusion method where the designed hydrogels can be obtained with well-defined mechanical properties and replicable 3D topologies. The developed protocol can be extended to different types of alginates and an ample range of concentrations. This makes it very attractive for various biomedical applications where strict control over structure-function relationships is desirable.

Evaluación de la exposición al polvo de carbón y de sílice en sitios de minería subterránea en tres departamentos de Colombia / Evaluation of the exposure to coal dust and prevalence of pneumoconiosis in underground mining in three Colombian departments

Introducción. La neumoconiosis de mineros del carbón es una enfermedad crónica e irreversible que se considera un problema de salud pública. Objetivo. Estimar la prevalencia de neumoconiosis y sus factores asociados en mineros de carbón de Boyacá, Cundinamarca y Norte de Santander. Materiales y métodos. Se hizo un estudio de corte transversal en 476 mineros. Se les hizo valoración médica, se tomaron radiografías de tórax siguiendo los criterios de la Organización Internacional del Trabajo, así como espirometrías, y se identificaron los polimorfismos de la glutatión S-transferasa y de las enzimas de reparación. Las asociaciones entre las condiciones ocupacionales y de la empresa con la neumoconiosis, se estudiaron usando modelos de regresión de Cox. Resultados. En 31 empresas se hicieron 479 monitorizaciones ambientales y se evaluaron 476 trabajadores cuyo tiempo de trabajo fluctuaba entre 10 y 57 años. La prevalencia de la neumoconiosis fue de 33,8 % (IC95% 27,0-41,3). En el modelo de regresión multivariado de Cox, con tiempo de riesgo constante para la neumoconiosis, esta se asoció significativamente con el trabajo en empresas medianas (razón de prevalencias, RP=2,00; IC95% 0,995- 2,690; p=0,052), con un nivel alto de exposición al polvo de carbón según el índice de exposición (RP=2,055; IC95% 1,043-4,048; p=0,038), y una antigüedad de 25 años o más (para 25,0 a 29,9 años: RP=2,199; IC95% 1,449-3,338; p=0,001). Conclusiones. La prevalencia de la neumoconiosis fue muy alta y se asoció a la exposición a altos niveles de polvo de carbón, a una exposición laboral mayor o igual a 25 años y al trabajo en empresas medianas.

Introduction: Coal workers' pneumoconiosis is a chronic and irreversible disease representing a public health problem. Objective: To estimate the prevalence of pneumoconiosis and its associated factors among underground coal miners in the Colombian departments of Boyacá, Cundinamarca and Norte de Santander. Materials and methods: We conducted a cross-sectional study of 476 miners to measure the prevalence of pneumoconiosis and its associated factors such as coal dust and silica levels, as well as the occupational conditions. The medical assessment and a chest x-ray were performed according to the International Labor Organization criteria, along with spirometry and the identification of glutathione S-transferase and repair enzyme polymorphisms. The associations were explored using Cox regression models. Results: We performed a total of 479 environmental monitoring sessions in 31 companies and we evaluated 476 workers with 10 to 57 years of mining work experience. The prevalence of pneumoconiosis was 33.8% (95% CI: 27.0 - 41.3%). In the Cox multivariate regression model with a constant risk time, pneumoconiosis was significantly associated with working in medium-sized companies (PR=2.00, 95% CI: 0.995 - 2.690; p=0.052), the level of severe exposure to coal dust (PR=2.055, 95% CI: 1.043 - 4.048; p=0.038), and working in underground mining for 25 years or more (for those with 25.0-29.9 years: PR=2.199, 95% CI: 1.449 - 3.338; p=0.001). Conclusions: The prevalence of pneumoconiosis was very high and was found to be associated with severe exposure to coal dust, work exposure for 25 years or more and working in medium-sized enterprises.

Caracterización de los accidentes de riesgo biológico y uso de profilaxis en trabajadores sanitarios por exposición ocupacional, que consultaron en el Programa Nacional de Lucha contra el SIDA desde enero a diciembre del año 2013

RESUMEN Una de las vías de transmisión del virus del VIH es la sanguínea a través de accidentes cortopunzantes, los trabajadores sanitarios que están expuestos a lesiones por pinchazos con agujas que contienen sangre infectada con el VIH, tienen un riesgo de 0.23 % de ser infectados. El objetivo de este estudio es caracterizar los accidentes de riesgo biológico y el uso de profilaxis post exposición ocupacional en los trabajadores sanitarios que consultaron en el Programa Nacional de Lucha contra el SIDA desde enero a diciembre del año 2013. Material y Método: Diseño observacional, descriptivo, de corte transverso. Fueron incluidos 66 fichas para este estudio. Las variables analizadas fueron: edad, sexo, procedencia, ocupación o puesto de trabajo, hora del accidente, exposición ocupacional, trabajador sanitario, paciente fuente, tipo de accidente laboral o clasificación del accidente según el riesgo, tipo de exposición, indicación de profilaxis post exposición, efectos colaterales de los medicamentos antiretrovirales. Resultados: 85% fueron mujeres y 15% fueron hombres. La edad media fue de 33,1 ± 8,9 (20 a 62) años. En cuanto a la profesión a los trabajadores sanitario los expuestos ocupacionalmente fueron el personal de enfermería en 36,6%; seguido de Personal de limpieza en 24,24%, y personal médicos en 18,8%. El accidente fue clasificado como leve en un 62,1 % y como grave en un 37,8%. El tipo de exposición, en un 65,1% fue de tipo 1 (pinchazos, corte con agujas acanalada o hueca, bisturí), La paciente fuente era conocido en un 54,5% de los casos. De entre los pacientes fuente conocidos, el 62% con serología positiva para el VIH, 77% inició Profilaxis Post Exposición. Solo 6% completó el esquema de tratamiento. De entre los que completaron PPE, uno de ellos presentó efectos colaterales (mareos, náuseas y eritema facial). Conclusión: La precaución universal es la primera línea de defensa para prevenir la exposición ocupacional. El asumir que todos los pacientes están potencialmente infectados constituye la única manera de optimizar las medidas para prevenir la trasmisión de esta patología, con aseguramiento de controles y medidas para completar la profilaxis si fuera necesario

ABSTRACT One of the routes of transmission of the HIV virus is blood through sharps accidents; health workers who are exposed to needle stick injuries that contain HIV-infected blood have a 0.23% risk of being infected. The objective of this study is to characterize the biological hazard accidents and the use of occupational post-exposure prophylaxis in health workers, who consulted in the National Program to Fight AIDS from January to December 2013. Material and Method: Observational, descriptive, cross-sectional design. 66 tokens were included for this study. The variables analyzed were: age, sex, origin, occupation or workplace, time of accident, occupational exposure, health worker, source patient, type of work accident or accident classification according to risk, type of exposure, indication of postprophylaxis exposure, side effects of antiretroviral drugs. Results: 85% were women and 15% were men. The mean age was 33.1 ± 8.9 (20-62) years. Health Workers more exposed were the nursing staff in 36.6%; followed by cleaners 24.24%, and medical personnel 18.8%. The accident was classified as mild in 62.1% and as severe in 37.8%. The type of exposure, in 65.1% was type 1 (punctures, cut with needles grooved or hollow, scalpel), the patient source was known in 54.5% of cases. Among the known source patients, 62% with serology positive for HIV, 77% started Prophylaxis Post Exposure. Only 6% completed the treatment schedule. Among those who completed PPE, one of them presented side effects (dizziness, nausea and facial erythema). Conclusion: Universal precaution is the first line of defense to prevent occupational exposure. Assuming that all patients are potentially infected is the only way to optimize measures to prevent the transmission of this pathology, with assurance of controls and measures to complete prophylaxis if necessary.

Evaluation of the exposure to coal dust and prevalence of pneumoconiosis in underground mining in three Colombian departments / Evaluación de la exposición al polvo de carbón y de sílice en sitios de minería subterránea en tres departamentos de Colombia

Introduction: Coal workers' pneumoconiosis is a chronic and irreversible disease representing a public health problem. Objective: To estimate the prevalence of pneumoconiosis and its associated factors among underground coal miners in the Colombian departments of Boyacá, Cundinamarca and Norte de Santander. Materials and methods: We conducted a cross-sectional study of 476 miners to measure the prevalence of pneumoconiosis and its associated factors such as coal dust and silica levels, as well as the occupational conditions. The medical assessment and a chest x-ray were performed according to the International Labor Organization criteria, along with spirometry and the identification of glutathione S-transferase and repair enzyme polymorphisms.The associations were explored using Cox regression models. Results: We performed a total of 479 environmental monitoring sessions in 31 companies and we evaluated 476 workers with 10 to 57 years of mining work experience. The prevalence of pneumoconiosis was 33.8% (95% CI: 27.0 - 41.3%). In the Cox multivariate regression model with a constant risk time, pneumoconiosis was significantly associated with working in medium-sized companies (PR=2.00, 95% CI: 0.995 - 2.690; p=0.052), the level of severe exposure to coal dust (PR=2.055, 95% CI: 1.043 - 4.048; p=0.038), and working in underground mining for 25 years or more (for those with 25.0-29.9 years: PR=2.199, 95% CI: 1.449 - 3.338; p=0.001). Conclusions: The prevalence of pneumoconiosis was very high and was found to be associated with severe exposure to coal dust, work exposure for 25 years or more and working in medium-sized enterprises

Introducción. La neumoconiosis de mineros del carbón es una enfermedad crónica e irreversible que se considera un problema de salud pública. Objetivo. Estimar la prevalencia de neumoconiosis y sus factores asociados en mineros de carbón de Boyacá, Cundinamarca y Norte de Santander. Materiales y métodos. Se hizo un estudio de corte transversal en 476 mineros. Se les hizo valoración médica, se tomaron radiografías de tórax siguiendo los criterios de la Organización Internacional del Trabajo, así como espirometrías, y se identificaron los polimorfismos de la glutatión S-transferasa y de las enzimas de reparación. Las asociaciones entre las condiciones ocupacionales y de la empresa con la neumoconiosis, se estudiaron usando modelos de regresión de Cox. Resultados. En 31 empresas se hicieron 479 monitorizaciones ambientales y se evaluaron 476 trabajadores cuyo tiempo de trabajo fluctuaba entre 10 y 57 años. La prevalencia de la neumoconiosis fue de 33,8 % (IC95% 27,0-41,3). En el modelo de regresión multivariado de Cox, con tiempo de riesgo constante para la neumoconiosis, esta se asoció significativamente con el trabajo en empresas medianas (razón de prevalencias, RP=2,00; IC95% 0,995- 2,690; p=0,052), con un nivel alto de exposición al polvo de carbón según el índice de exposición (RP=2,055; IC95% 1,043-4,048; p=0,038), y una antigüedad de 25 años o más (para 25,0 a 29,9 años: RP=2,199; IC95% 1,449-3,338; p=0,001). Conclusiones. La prevalencia de la neumoconiosis fue muy alta y se asoció a la exposición a altos niveles de polvo de carbón, a una exposición laboral mayor o igual a 25 años y al trabajo en empresas medianas.

Oxidative stress and repetitive element methylation changes in artisanal gold miners occupationally exposed to mercury.

Mercury (Hg) exposure is a public health concern due to its persistence in the environment and its high toxicity. Such toxicity has been associated with the generation of oxidative stress in occupationally exposed subjects, such as artisanal gold miners. In this study, we characterize occupational exposure to Hg by measuring blood, urine and hair levels, and investigate oxidative stress and DNA methylation associated with gold mining. To do this, samples from 53 miners and 36 controls were assessed. We show higher levels of oxidative stress marker 8-OHdG in the miners. Differences in LINE1 and Alu(Yb8) DNA methylation between gold miners and control group are present in peripheral blood leukocytes. LINE1 methylation is positively correlated with 8-OHdG levels, while XRCC1 and LINE1 methylation are positively correlated with Hg levels. These results suggest an effect of Hg on oxidative stress and DNA methylation in gold miners that may have an impact on miners' health.

TET-Catalyzed 5-Hydroxymethylation Precedes HNF4A Promoter Choice during Differentiation of Bipotent Liver Progenitors.

Understanding the processes that govern liver progenitor cell differentiation has important implications for the design of strategies targeting chronic liver diseases, whereby regeneration of liver tissue is critical. Although DNA methylation (5mC) and hydroxymethylation (5hmC) are highly dynamic during early embryonic development, less is known about their roles at later stages of differentiation. Using an in vitro model of hepatocyte differentiation, we show here that 5hmC precedes the expression of promoter 1 (P1)-dependent isoforms of HNF4A, a master transcription factor of hepatocyte identity. 5hmC and HNF4A expression from P1 are dependent on ten-eleven translocation (TET) dioxygenases. In turn, the liver pioneer factor FOXA2 is necessary for TET1 binding to the P1 locus. Both FOXA2 and TETs are required for the 5hmC-related switch in HNF4A expression. The epigenetic event identified here may be a key step for the establishment of the hepatocyte program by HNF4A.

Frog skin cultures secrete anti-yellow fever compounds.

There is an urgent need to develop novel antimicrobial substances. Antimicrobial peptides (AMPs) are considered as promising candidates for future therapeutic use. Because of the re-emergence of the Flavivirus infection, and particularly the yellow fever virus (YFV), we have compared the antiviral activities from skin secretions of seven different frog species against YFV (strain 17D). Secretions from Sphaenorhynchus lacteus, Cryptobatrachus boulongeri and Leptodactylus fuscus displayed the more powerful activities. S. lacteus was found to inhibit viral lysis of Vero E6 cells even at the highest viral concentration evaluated of 10 LD50. We also report the identification of a novel frenatin-related peptide from S. lacteus and found that this peptide-on its own-can lead to 35% protection against YVF, while displaying no cytotoxicity against somatic cells even at fivefold higher concentrations. These results are attractive and support the need for continued exploration of new sources of AMPs from frog skin secretions such as those described here in the development of new compounds for the treatment of infectious diseases in general and specific viral infections in particular.

HLA-DRB1*14 is a protective allele for multiple sclerosis in an admixed Colombian population.

OBJECTIVE: The aim of this study was to determine ancestry informative markers, mitochondrial DNA haplogroups, and the association between HLA-DRB1 alleles and multiple sclerosis (MS) in a group of patients from Bogotá, Colombia. METHODS: In this case-control study, genomic DNA was isolated and purified from blood samples. HLA-DRB1 allele genotyping was done using PCR. Mitochondrial hypervariable region 1 was amplified and haplogroups were determined using HaploGrep software. Genomic ancestry was estimated by genotyping a panel of ancestry informative markers. To test the association of HLA polymorphisms and MS, we ran separate multivariate logistic regression models. Bonferroni correction was used to account for multiple regression tests. RESULTS: A total of 100 patients with MS (mean age 40.4 ± 12 years; 70% females) and 200 healthy controls (mean age 37.6 ± 11 years; 83.5% females) were included in the analysis. Ancestry proportions and haplogroup frequencies did not differ between patients and controls. HLA-DRB1*15 was present in 31% of cases and 13.5% of controls, whereas HLA-DRB1*14 was present in 5% of cases and 15.5% of controls. In the multivariate model, HLA-DRB1*15 was significantly associated with MS (odds ratio [OR] = 3.05, p < 0.001), whereas HLA-DRB1*14 was confirmed as a protective factor in our population (OR = 0.16, p = 0.001). CONCLUSIONS: This study provides evidence indicating that HLA-DRB1*15 allele confers susceptibility to MS and HLA-DRB1*14 allele exerts resistance to MS in a highly admixed population. This latter finding could partially explain the low prevalence of MS in Bogotá, Colombia.

Exposure to pesticide mixtures and DNA damage among rice field workers.

This study describes the use of pesticides mixtures and their potential association with comet assay results in 223 rice field workers in Colombia. Thirty-one pesticides were quantified in blood, serum, and urine (15 organochlorines, 10 organophosphorus, 5 carbamates, and ethylenethiourea), and the comet assay was performed. Twenty-four (77.42%) pesticides were present in the workers. The use of the maximum-likelihood factor analysis identified 8 different mixtures. Afterwards, robust regressions were used to explore associations between the factors identified and the comet assay. Two groups of mixtures--α-benzene hexachloride (α-BHC), hexachlorobenzene (HCB), and ß-BHC (ß: 1.21, 95% confidence interval [CI]: 0.33-2.10) and pirimiphos-methyl, malathion, bromophos-methyl, and bromophos-ethyl (ß: 11.97, 95% CI: 2.34-21.60)--were associated with a higher percentage of DNA damage and comet tail length, respectively. The findings suggest that exposure to pesticides varies greatly among rice field workers.