Genetic damage in coal miners evaluated by buccal micronucleus cytome assay.

During coal mining activities, large quantities of coal dust, ashes, polycyclic aromatic hydrocarbons and metals are released into the environment. This complex mixture presents one of the most important occupational hazards for health of workers. The aim of the present study was to evaluate the genetic damage together with the presence of inorganic elements, in an exposed workers population to coal mining residues of Guajira-Colombia. Thus, 100 exposed workers and 100 non-exposed control individuals were included in this study. To determine genetic damage we assessed the micronucleus (MN) frequencies and nuclear buds in buccal mucosa samples (BMCyt) assay, which were significantly higher in the exposed group than non-exposed control group. In addition, karyorrhectic and karyolytic cells were also significantly higher in the exposed group (cell death). No significant difference was observed between the exposed groups engaged in different mining activities. No correlation between age, alcohol consumption, time of service and MN assay data were found in this study. However, the content of inorganic elements in blood samples analyzed by a Particle-induced X-ray emission technique (PIXE) showed higher values of silicon (Si) and aluminum (Al) in the exposed group. In this study we discuss the possibility of DNA damage observed in the mine workers cells be a consequence of oxidative damage.

Polimorfismo inserción/deleción del gen de la enzima convertidora de angiontensina y enfermedad coronaria en la población de Montería, Córdoba / Insertion/deletion polymorphism of the angiotensin converting enzyme gene and coronary artery disease in the population of Monteria, Cordoba

Antecedentes y objetivo: el polimorfismo inserción/deleción del gen de la enzima convertidora de angiotensina, ha sido identificado como un potente factor de riesgo de enfermedad coronaria. Para la población de Montería se desconocen las frecuencias con las que se expresan los alelos de este gen y el carácter de su interacción con condiciones de riesgo cardiovascular. El objetivo de este trabajo fue determinar, para dicha población, la asociación de este polimorfismo y el riesgo de sufrir enfermedad coronaria. Método: se llevó a cabo un estudio retrospectivo con 70 casos y 70 controles; como casos se consideraron pacientes con padecimientos coronarios confirmados por electrocardiograma, remitidos a la Organización Cardiodiagnóstico de Córdoba, y como controles individuos voluntarios sin antecedentes cardiovasculares y sin relación filial. El ADN requerido se extrajo a partir de sangre periférica. La caracterización del polimorfismo se hizo mediante reacción en cadena de la polimerasa. Resultados: la distribución de genotipos de la enzima convertidora de angiotensina en pacientes casos no fue significativamente diferente a la estimada en pacientes controles (X2=3.687, p=0,1583). El genotipo más frecuente en la población fue ID (40,72%). En el grupo casos, el genotipo II fue más frecuente que el genotipo DD comparado con el grupo control (p<0,05). El modelo de regresión logística múltiple ajustado, indicó no significancia del genotipo DD como factor de riesgo coronario (razón de disparidad = 0,51 IC95% = 0,25 – 1,06). Conclusión: el polimorfismo I/D del gen de la enzima convertidora de angiotensina no mostró ser un factor de riesgo significativo para enfermedad coronaria en la población de Montería.

Background and Objective: the insertion/deletion polymorphism of the gene for angiotensin converting enzyme has been identified as a potent risk factor for coronary heart disease. For the population of Monteria, the frequency with which the alleles of this gene are expressed and the nature of its interaction with cardiovascular risk conditions, are not known. The aim of this work was to determine the association of this polymorphism and the risk of coronary heart disease in this population. Methods: a retrospective study of 70 cases and 70 controls was conducted. Cases were the patients with coronary disease confirmed by electrocardiogram , reported to the Cordoba Cardiodiagnosis Organization and the control ones were volunteers without history of cardiovascular disease and without filial relationship. Required DNA was extracted from peripheral blood. Polymorphism characterization was done by the polymerase chain reaction. Results: the distribution of genotypes of the angiotensin converting enzyme gene in patients cases was not significantly different from that estimated in control patients (X2 = 3.687, p = 0.1583). The most common genotype in the population was ID (40.72%). In the group cases, genotype II was more frequent than the DD genotype compared with the control group (p < 0,05). The multiple logistic regression adjusted model indicated no significance of DD genotype as coronary risk factor (odds ratio = 0.51 95% CI = 0.25 to 1.06). Conclusion: I/D polymorphism of the angiotensin converting enzyme gene did not show to be a significant risk factor for coronary heart disease in the population of Monteria.

Assessment of DNA damage in coal open-cast mining workers using the cytokinesis-blocked micronucleus test and the comet assay.

Coal mining is one of the most important causes of environmental pollution, as large quantities of coal dust particles are emitted. Colombia-South America has large natural coal reserves and "El Cerrejón" is the world's largest open-cast mine located in the northern department of Guajira. The aim of the present study was to evaluate genotoxic effects in a population exposed to coal residues from the open-cast mine "El Cerrejón". 100 exposed workers and 100 non-exposed control individuals were included in this study. The exposed group was divided according to different mining area activities: (i). Transport of extracted coal, (ii). Equipment field maintenance, (iii). Coal stripping and, (iv). Coal embarking. Blood samples were taken to investigate biomarkers of genotoxicity, specifically, primary DNA damage as damage index (DI), tail length and% of tail DNA using the Comet assay (alkaline version) and chromosome damage as micronucleus (MN) frequency in lymphocytes. Both biomarkers showed statistically significantly higher values in the exposed group compared to the non-exposed control group. No difference was observed between the exposed groups executing different mining activities. These results indicate that exposure to coal mining residues may result in an increased genotoxic exposure in coal mining workers. We did not find a correlation between age, alcohol consumption and service time with the biomarkers of genotoxicity. Our results are the first data of genotoxic effects induced by coal mining exposure in Colombia, and thus, contribute to the exploration of test batteries use for monitoring of exposed populations and may stimulate designing control, hygiene and prevention strategies for occupational health risk assessment in developing countries.

Modelación molecular y variación estructural de las integrasas de dos retrovirus humanos: HTLV-I y VIH-1 / Molecular modeling and structural variation of two human retrovirus integrases: HTLV-I and HIV-1

Objetivo: Analizar las características moleculares y de variación de secuencias de las integrasas del HTLV-I y del VIH-1 y sus variantes poblacionales. Metodología: Análisis de secuencias y estructuras obtenidas de diferentes bases de datos; para ello se utilizaron programas computacionales de modelación de estructuras proteicas e identificación de sustituciones polimórficas en secuencias de aminoácidos de integrasas del HTLV-I y VIH-1 previamente reportadas. Materiales y métodos: Tanto la integrasa del HTLV-I como la del VIH-1 son proteínas compuestas por 288 residuos de aminoácidos. Se encontró un parecido de estructuras terciarias entre los dominios catalíticos de las IN de VIH-1, ASV y RSV con la del HTLV- I. A partir de 103 secuencias completas de la integrasa del VIH-1 se registraron, en 46 codones, un total de 53 sustituciones que se localizaron en diferentes posiciones de la proteína nativa; las más frecuentes fueron: N27G (32,1%), A265V (30,1%), L101I (31,1%) y T123A (27,0%). Ninguna de las sustituciones más frecuentemente encontradas generó un cambio en el plegamiento nativo de la correspondiente región. Conclusión: La estructura tridimensional del dominio central catalítico de la integrasa condicionaría su actividad y su relación con moléculas potencialmente inhibidoras. Las sustituciones observadas fueron neutrales sin alterar la estructura nativa. Los resultados obtenidos confirman que la integrasa es un nuevo y promisorio blanco para el desarrollo de terapias antirretrovirales más efectivas en el siglo XXI...

Objective: To analyze the molecular characteristics and aminoacid sequence variations of HTLV-I and of HIV-1 integrases and their population variants. Materials and methods: Data mining and analysis of integrase sequences and protein structure data bases by using appropriate software for modelling and search for polymorphic substitutions in HTLV-I and HIV-1 integrase amino acid sequences previously reported. Results: HTLV-I and HIV-1 integrases are proteins of 288 amino acid residues. Structural modeling of tertiary folding of HTLV-I integrase catalytic central domain’s, showed closed structural characteristic with those of HIV-1, ASV and RSV. From 103 full amino acid sequences of HIV-1 integrase, 53 substitutions located in 46 different codons were recorded. The more frequents correspond to N27G (32,1%), L101I (31,1%), A265V (30,1%) and T123A (27,0%). None of these frequent substitutions introduced changes in the folding of HIV-1 native integrase. Conclusion: The tridimensional structure of central catalytic domain would influence the integrase activity and its relationship with potentially inhibitory molecules. Those observed aminoacid substitutions were neutral and do not alter the native protein structure. Our data confirm those previously published, and enable us to propose that IN is a new and promissory target for develop more effective antiviral therapies in the XXI century...

Sindrome autoinmune en la paraparesia tropical espastica/ mielopatia asociada a la infeccion por el virus linfotropico / Autoimmune syndrome in the tropical spastic paraparesis/myelopathy associated with human T-lymphotropic virus infections

Introduccion. Trabajos previos han aportado evidencias de que en la paraparesia espastica tropical/mielopatia asociada con el virus linfotropico humano tipo I, existe un componente autoinmune asociado a su patogenesis. Objetivo. Evaluar el estado autoinmune y la existencia de mimetismo molecular en pacientes con paraparesia espastica tropical del pacifico colombiano. Materiales y metodos. A partir de muestras de plasma de 37 pacientes con paraparesia espastica tropical/mielopatia asociada al HTLV-I, 10 con leucemia de celulas T del adulto, 22 individuos portadores asintomáticos y 20 seronegativos para el HTLV-I, se determinaron niveles plasmaticos de anticuerpos antinucleares y anticardiolipina-2 y de interferon e interleucina- 4. Se evaluo, por Western blot, la reactividad cruzada de plasmas contra proteinas obtenidas de varias fuentes celulares normales del sistema nervioso. Ademas, se estudio la reactividad cruzada de plasmas de seropositivos y del anticuerpo monoclonal LT4 anti-taxp40 en secciones de medula espinal de ratas Wistar no infectadas. Resultados. El 70,2 por ciento y el 83,8 por ciento de los pacientes con paraparesia espastica tropical fueron reactivos para anticuerpos ANA y ACL-2, respectivamente, en contraste con los de leucemia de celulas T del adulto y los seropositivos asintom¨¢ticos (P<0,001). Ademas, el 70,3 por ciento y el 43,2 por ciento de los pacientes con paraparesia espastica tropical tuvieron niveles detectables de IFN-¦Ã e IL-4, respectivamente. El anticuerpo LT4 anti tax-p40 y los plasmas de paraparesia espastica tropical/mielopatia asociada al HTLV-I mostraron una reaccion cruzada con una proteina de PMr 33-35 kDa, obtenida del nucleo de neuronas de la medula espinal de ratas Wistar no infectadas. Conclusion. Se obtuvieron evidencias que apoyan la existencia de un sindrome autoinmune mediado por mimetismo molecular como parte de la etiopatogenesis de la degeneracion axonal observada en la paraparesia espastica tropical en pacientes colombianos de la costa pacifica.

[Autoimmune syndrome in the tropical spastic paraparesis/myelopathy associated with human T-lymphotropic virus infections]. / Síndrome autoinmune en la paraparesia tropical espástica/mielopatía asociada a la infección por el virus linfotrópico humano tipo I de la costa pacífica colombiana.

INTRODUCTION: Previous reports have given evidence that in tropical spastic paraparesis (TSP)/human T-lymphotrophic virus (HTLV-I)-associated myelopathy (HAM), an autoimmune process occurs as part of its pathogenesis. OBJECTIVE: The roles of autoimmunity and the molecular mimicry was evaluated in TSP/HAM patients. MATERIALS AND METHODS: Plasma samples were characterized from patients in the Pacific coastal region of Colombia. Thirty-seven were identified as TSP/HAM, 10 were diagnosed with adult T-cell leukemia virus, 22 were asymptomatic carriers but seropositive for HTLV-I and 20 were seronegative and served as negative controls. Plasmatic levels of the following were determined: antinuclear antibody (ANA) levels, anticardiolipine-2 (ACL-2), interferon- (IFN-gamma) and interleukin-4 (IL-4). Using Western blot, the crossreactivity of the seropositive and seronegative samples was evaluated against proteins extracted from several central nervous system components of non infected Wistar rats. The HTLV-I seropositive plasmas were crossreacted with a monoclonal tax (LT4 anti-taxp40) from spinal cord neurons of non infected Wistar rats. RESULTS: Of the TSP/HAM patients, 70.2% were reactive against ANA and 83.8% against ACL-2, in contrast with those ATL and asymptomatic seropositives subjects that were not reactive (P<0.001). Moreover, 70.3% had detectable levels of IFN and 43.2% had detectable IL-4. LT4 anti-taxp40 and plasma of TSP/HAM exhibited cross reactivity with a MW 33-35 kDa protein from the rat spinal cord nuclei. CONCLUSION: Support was provided for the existence of an autoimmune syndrome mediated by molecular mimicry; the syndrome was responsible for some of the axonal degeneration observed in TSP/HAM patients.

Genotoxic effects in wild rodents (Rattus rattus and Mus musculus) in an open coal mining area.

Coal is a mixture of a variety of compounds containing mutagenic and carcinogenic polycyclic aromatic hydrocarbons. Exposure to coal is considered as an important non-cellular and cellular source of reactive oxygen species that can induce DNA damage. In addition, spontaneous combustion can occur in coal mining areas, further releasing compounds with detrimental effects on the environment. In this study the comet assay was used to investigate potential genotoxic effects of coal mining activities in peripheral blood cells of the wild rodents Rattus rattus and Mus musculus. The study was conducted in a coal mining area of the Municipio de Puerto Libertador, South West of the Departamento de Cordoba, Colombia. Animals from two areas in the coal mining zone and a control area located in the Municipio de Lorica were investigated. The results showed evidence that exposure to coal results in elevated primary DNA lesions in blood cells of rodents. Three different parameters for DNA damage were assessed, namely, DNA damage index, migration length and percentage damaged cells. All parameters showed statistically significantly higher values in mice and rats from the coal mining area in comparison to the animals from the control area. The parameter "DNA Damage Index" was found to be most sensitive and to best indicate a genotoxic hazard. Both species investigated were shown to be sensitive indicators of environmental genotoxicity caused by coal mining activities. In summary, our study constitutes the first investigation of potential genotoxic effects of open coal mining carried out in Puerto Libertador. The investigations provide a guide for measures to evaluate genotoxic hazards, thereby contributing to the development of appropriate measures and regulations for more careful operations during coal mining.

[Molecular evolution and geographic origins of type 1 human lymphotrophic virus in Colombia detected by RFLP polymorphism]. / Reconstrucción de la evolución molecular de la infección actual por el virus linfotrópico humano tipo I en Colombia.

The human T-lymphotropic virus type I (HTLV-I) infection is a public health problem in many endemic areas of Colombia. The subtyping of HTLV-I was based on the analysis of restriction fragment length polymorphisms (RFLP) in 3'LTR proviral DNA. From 31 HTLV-I isolates collected throughout Colombia, a RFLP analysis in a 737 bp 3'LTR fragment was performed. Fifty-eight percent (18/31) were identified as the Cosmopolitan subtype a, 19.4% (6/31) in the West African subtype b, 12.9% (4/31) in the Cosmopolitan subtype b and 9.6% (3/31) in the West African subtype c. The phylogenetic analysis of 3'LTR nucleotide sequences indicated that all the isolates in the current study were in the subgroup B or Japanese, in contrast with the highly divergent isolates from native Amerindians grouped in subgroup a or Transcontinental. The supported hypothesis was that of a post-Columbus introduction of virus represented in the African-American communities of the Colombian South Pacific. Some viral isolates from Colombian native Amerindians exhibited a nucleotide variation compatible with a Paleolithic introduction of the virus. The genetic diversity of HTLV-I in Colombia is complex and probably represents several independent introductions of lymphotropic virus.

Reconstrucción de la evolución molecular de la infección actual por el virus linfotrópico humano tipo I en Colombia / Evolutionary and geographic origins of human lymphotropic virus in Colombia detected by RFLP polymorphisms

La infección por el virus linfotrópico humano tipo I (HTLV-I) es un problema de salud pública en varias zonas endémicas de Colombia. La subtipificación del HTLV-I se basa en los análisis de polimorfismos en el tamaño de fragmentos de restricción (RFLP) de la región 3’LTR del ADN proviral. A partir de 31 aislamientos de HTLV-I recolectados en diferentes regiones del territorio nacional se realizó un análisis de RFLP en un fragmento de ADN de 737 pb de la región LTR. El 58,1% (18/31) se incluyó dentro del subtipo Cosmopolita a; el 19,4% (6/31) en el Africano b; el 12,9% (4/31) en el Cosmopolita b, y el 9,6% (3/31) en el Africano c. Con base en análisis filogenéticos de secuencias nucleotídicas del 3’LTR, se demostró que los aislamientos colombianos incluidos en este trabajo se ubicaron dentro del subgrupo B o japonés, lo cual muestra gran divergencia con aquellos aislamientos de indígenas colombianos previamente reportados que se incluyeron dentro del subgrupo A o transcontinental. Nuestros datos apoyan la hipótesis de una introducción poscolombina del HTLV-I a Colombia que estaría representada en las comunidades negras de la costa del Pacífico del sur de Colombia que tuvieron ancestros africanos. Algunos aislamientos virales de indígenas colombianos mostraron una variación nucleotídica compatible con una introducción paleolítica. En su conjunto, los resultados obtenidos permiten postular que la actual diversidad genética del HTLV-I en Colombia es compleja y es el resultado de varios eventos de introducción, temporalmente separados.

The human T-lymphotropic virus type I (HTLV-I) infection is a public health roblem in many endemic areas of Colombia. The subtyping of HTLV-I was based on the analysis of restriction fragment length polymorphisms (RFLP) in 3’LTR proviral DNA. From 31 HTLV-I isolates collected throughout Colombia, a RFLP analysis in a 737 bp 3’LTR fragment was performed. Fifty-eight percent (18/31) were identified as the Cosmopolitan subtype a, 19.4% (6/31) in the West African subtype b, 12.9% (4/31) in the Cosmopolitan subtype b and 9.6% (3/31) in the West African subtype c. The phylogenetic analysis of 3’LTR nucleotide sequences indicated that all the isolates in the current study were in the subgroup B or Japanese, in contrast with the highly divergent isolates from native Amerindians grouped in subgroup a or Transcontinental. The supported hypothesis was that of a post-Columbus introduction of virus represented in the African-American communities of the Colombian South Pacific. Some viral isolates from Colombian native Amerindians exhibited a nucleotide variation compatible with a Paleolithic introduction of the virus. The genetic diversity of HTLV-I in Colombia is complex and probably represents several independent introductions of lymphotropic virus.

Estudio de la seroprevalencia de la infección por los virus linfotrópicos humanos (HTLV) I y II en poblaciones del departamento de Córdoba, Colombia / Study of seroprevalence of infection by humanT-Lymphotropic virus I/II in Cordoba, Colombia

Introducción: Se determinó la seroprevalencia de los virus linfotrópicos humanos tipos I y II (HTLV-I y II) en varios municipios del Departamento de Córdoba. Materiales y métodos: Se analizaron 962 muestras de suero mediante la prueba de ELISA y de Western blot confirmatorio. Se analizaron genéticamente 5 aislamientos virales por RFLP y secuenciación de la región LTR. Resultados: Se confirmaron 20 aislamientos como HTLV-I y uno como HTLV-II. La seroprevalencia de la infección por el HTLV-I en la muestra obtenida del departamento de Córdoba fue 2.1/100 (20/962), y para el HTLV-II 0.1/100 (1/962). Mediante análisis genéticos se determinó que tres correspondieron al subtipo africano b y dos el cosmopolita a. Conclusión: Este es el primer registro de la infección tanto por HTLV-I como por HTLV-II informado para el departamento de Córdoba en Colombia