Daños de salud respiratoria en comunas expuestas a centrales termoeléctricas a carbón en el norte de Chile: análisis de datos secundarios / Respiratory health damage in communes exposed to coal-fired power plants in northern Chile

INTRODUCCIÓN: En Chile, el funcionamiento de las Centrales Termoeléctricas de Carbón (CTEC) representan un problema de salud pública debido a las consecuencias sanitarias que tienen en la población. Se han notificado daños en el sistema respiratorio. Materiales y MÉTODOS: Se realizó un estudio ecológico, para evaluar los egresos hospitalarios de las personas que viven en las ciudades donde operan las CTEC (Tocopilla y Huasco), se comparó con una ciudad de control sin CTEC (Caldera), las comunas evaluadas tienen condiciones sociodemográficas similares. Se calcularon las tasas de morbilidad y tasas de morbilidad estandarizadas (SMR). RESULTADOS: La tasa de morbilidad por enfermedades respiratorias en Tocopilla (2016) fue de 152,5 por 10.000 habitantes (habs) y para Huasco es de 135,2 por 10.000 habs. En la ciudad control, Caldera, la tasa es de 40,9 por 10.000 habs. Además, los habitantes de Tocopilla tienen 2,42 más riesgo de padecer bronquitis o bronquiolitis, 90% más riesgo de presentar enfermedades crónicas de las vías respiratorias bajas y 2,14 veces más riesgo de enfermar por asma. En Huasco, la población tiene 2,49 veces más riesgo de padecer enfermedades de las vías respiratorias inferiores con respecto a la región y 3,19 veces más riesgo de presentar asma. CONCLUSIONES: El asma y la bronquitis, son las patologías que mostraron mayores riesgos en las ciudades de Tocopilla y Huasco. Nuestros hallazgos son similares a otras investigaciones realizadas en comunidades expuestas a centrales termoeléctricas de carbón. Es necesario tomar medidas urgentes para proteger la salud de la población.

INTRODUCTION: In Chile, coal-fired power plants (CTEC) operate represents public health problems due to the health consequences for the population. Damage to the respiratory system is reported. MATERIALS AND METHODS: Ecological study to evaluate hospital discharges in people living in cities where CTEC operates (Tocopilla and Huasco) were compared to a control city without CTEC (Caldera), all of them with similar sociodemographic conditions. Morbidity rates and Standardized Morbidity Ratios (SMR) were calculated. RESULTS: The respiratory disease morbidity rate in Tocopilla (2016) was 152.5 per 10,000 inhabitants (habs) and for Huasco it is 135.2 per 10,000 inhabitants. In the control city, Caldera, the rate is 40.9 per 10,000 habs. In addition, the inhabitants of Tocopilla have a 2.42 times increased risk of bronchitis or bronchiolitis, 90% higher risk of chronic lower respiratory diseases and 2.14 times more risk of asthma sickness. In Huasco, the population is 2.49 times more at risk of lower respiratory diseases compared to the region and 3.19 times more at risk of asthma. CONCLUSIONS: Asthma and bronchitis are the pathologies that showed the greatest risks in the cities of Tocopilla and Huasco. Our findings are similar to other research conducted in communities exposed to coal-fired power plants. Urgent action is needed to protect the health of the population.

[Exposure to contaminants from coal-fired thermoelectric plants and children's health: What is the international and national evidence?] / Exposición a contaminantes provenientes de termoeléctricas a carbón y salud infantil: ¿Cuál es la evidencia internacional y nacional?

Coal-fired power plants (CFPP) represent a health risk to the exposed communities. A review of national and international scientific literature was made focused on the health effects on children and exposure to air emissions from CFPP. Twenty-one articles were included for full-text review, where effects on child health mainly related to the biomarkers presence of exposure and effect, pe rinatal, neurobehavioral and respiratory damages were measured. Exposure to CFPP emissions in pregnancy was associated with low birth weight and very low birth weight, shorter height, smaller head circumference (HC) diameter, and prematurity; the HC diameter increased in newborns after the CFPP closure. Lower coefficient of development (CD) and intelligence quotient (IQ) were found in children exposed to CFPP emissions compared with unexposed ones; CD increased when the plant was closed. On the other hand, living in areas with mercury emission sources (associated with CFPP and cement plants that work with coal) was associated with an increased risk of autism. In respira tory health, the articles were consistent with reporting lower pulmonary function in children living in areas exposed to coal combustion sources compared with groups of unexposed children. There is a great need to open the debate in Chile on the controllable risks faced by the child population as a result of power generation plants located in Chile.

Exposición a contaminantes provenientes de termoeléctricas a carbón y salud infantil: ¿Cuál es la evidencia internacional y nacional? / Exposure to contaminants from coal-fired thermoelectric plants and children's health: what is the international and national evidence?

Resumen: Las centrales termoeléctricas (CTE) a carbón representan un riesgo para la salud de las comunidades expuestas. Se realizó una revisión de la literatura científica nacional e internacional enfocada en los efectos en salud de niños y la exposición a emisiones al aire provenientes de CTE a carbón. Se inclu yeron 21 artículos para su revisión en texto completo, donde se midieron efectos en salud infantil relacionados a presencia de biomarcadores de exposición y efecto, daños perinatales, neuroconductuales y respiratorios principalmente. La exposición a emisiones de CTE a carbón en el embarazo se asoció a niños con bajo peso y muy bajo peso al nacer, menor talla, menor diámetro de Circunfe rencia del Cráneo (CC) y prematuridad; el diámetro de CC aumentó en recién nacidos después del cierre de CTE. Se encontraron menor coeficiente de desarrollo (CD) y coeficiente intelectual (CI) en niños expuestos a emisiones de CTE a carbón comparados con no expuestos; CD aumentó cuando la central fue cerrada. Por otro lado, vivir en zonas con fuentes de emisión de mercurio (asociadas a CTE y plantas de cemento que funcionan con carbón) se asoció con mayor riesgo de autismo. En salud respiratoria, los artículos fueron consistentes en reportar menor función pulmonar en niños residentes en zonas expuestas a fuentes de combustión de carbón comparados con grupos de niños no expuestos. Es muy necesario abrir el debate en Chile sobre los riesgos controlables a los que se enfrenta la población infantil a consecuencia de plantas generadoras de energía instaladas en Chile.

Abstract: Coal-fired power plants (CFPP) represent a health risk to the exposed communities. A review of national and international scientific literature was made focused on the health effects on children and exposure to air emissions from CFPP. Twenty-one articles were included for full-text review, where effects on child health mainly related to the biomarkers presence of exposure and effect, pe rinatal, neurobehavioral and respiratory damages were measured. Exposure to CFPP emissions in pregnancy was associated with low birth weight and very low birth weight, shorter height, smaller head circumference (HC) diameter, and prematurity; the HC diameter increased in newborns after the CFPP closure. Lower coefficient of development (CD) and intelligence quotient (IQ) were found in children exposed to CFPP emissions compared with unexposed ones; CD increased when the plant was closed. On the other hand, living in areas with mercury emission sources (associated with CFPP and cement plants that work with coal) was associated with an increased risk of autism. In respira tory health, the articles were consistent with reporting lower pulmonary function in children living in areas exposed to coal combustion sources compared with groups of unexposed children. There is a great need to open the debate in Chile on the controllable risks faced by the child population as a result of power generation plants located in Chile.

H2 O2 activates matrix metalloproteinases through the nuclear factor kappa B pathway and Ca(2+) signals in human periodontal fibroblasts.

BACKGROUND: The mechanisms involved in reactive oxygen species and matrix metalloproteinase (MMP)-mediated periodontal tissue breakdown are unknown. OBJECTIVE: To determine the effect of H2 O2 in MMP-2 and MMP-9 activity, and the involvement of nuclear factor kappa B (NFκB) and Ca(2+) -mediated signals in human periodontal ligament fibroblasts. MATERIAL AND METHODS: Primary cultures were characterized for their phenotype and exposed for 24 h to sublethal doses (2.5-10 µm) of H2 O2 or control media. NFκB involvement was evaluated through immunofluorescence of p65 subunit, using the NFκB blocking peptide SN50 and catalase. Ca(2+) signals were analyzed by loading the cells with Fluo4-AM and recording the fluorescence changes in a confocal microscope before and after the addition of H2 O2 . 1,2-bis(o-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl was used to chelate intracellular Ca(2+) . The activity and levels of MMP-2 and MMP-9 were analyzed by gelatin zymogram and densitometric scanning, and enzyme-linked immunosorbent assay, respectively. Statistical analysis was performed with stata V11.1 software using the ANOVA test. RESULTS: H2 O2 at concentrations of 2.5-5 µm induced Ca(2+) signaling and NFκB subunit p65 nuclear translocation, whereas catalase, SN50 and BAPTA-AM prevented p65 nuclear translocation. H2 O2 at 2.5-5 µm significantly increased MMP-9 and MMP-2 activity, while SN50 resulted in lower MMP-2 and MMP-9 activity rates compared with controls. CONCLUSION: Sublethal H2 O2 induces Ca(2+) -dependent NFκB signaling with an increase in MMP gelatinolytic activity in human periodontal ligament.

Reconstrucción anatómica de ligamento cruzado anterior con banda simple a través del uso de un portal medial accesorio: resultados clínicos e imagenológicos en seguimiento a mediano plazo / Anatomic anterior cruciate ligament reconstruction with single band through an accessory medial portal

Objetivo: Evaluar los resultados clínicos de la reconstrucción anatómica de Ligamento Cruzado Anterior (LCA) con una banda a través de un portal medial accesorio. Material y método: serie prospectiva, 52 pacientes con reconstrucción anatómica de LCA a través de un portal medial accesorio. Edad promedio: 26,4 años (15-39), 68 por ciento hombres, 32 por ciento mujeres. Seguimiento promedio: 39 meses (36-53). Evaluación de estabilidad anteroposterior mediante la prueba artrométrica KT-1000 y estabilidad rotacional con test de Pivot-shift. Resultados clínicos evaluados con scores de Lysholm e International Knee Documentation Committee Score (IKDC). Se solicitó resonancia magnética (RM) 6 meses post-reconstrucción para evaluar la madurez e incorporación del injerto. También se registraron las complicaciones. Resultados: diferencia promedio de KT-1000 entre ambas rodillas: 2,09 mm, 92,4 por ciento de los pacientes entre 1-3 mm, 3,8 por ciento entre 3-5 mm, y 3,8 por ciento con más de 5 mm. Pivot Shift negativo en 86,5 por ciento y presente en 13,5 por ciento de los pacientes. IKDC promedio: 89,2 puntos, Lysholm promedio: 93,8 puntos. Integración del injerto en RM: 100 por ciento de los pacientes. 3 pacientes (5,8 por ciento) presentaron una re-rotura del injerto (20 meses promedio) y 1 paciente (1,9 por ciento) presentó una lesión condral femoral sintomática (12 meses). Discusión y Conclusiones: nuestro estudio muestra buenos y excelentes resultados para la reconstrucción anatómica de LCA con banda simple con respecto a estabilidad anterior y rotacional, scores clínicos e integración del injerto. Nuestra tasa de re-roturas es similar a las tasas descritas en la literatura para reconstrucciones transtibiales, lo que podría explicarse por otros factores involucrados en este proceso independientes de la posición del injerto. Nivel de evidencia: III. Tipo de estudio: Estudio de cohorte prospectivo

Introduction: The aim of this study was to evaluate the clinical results of anatomic single bundle anterior cruciate ligament (ACL) reconstruction through an accessory medial portal. Methods: prospective case series. Fifty-two patients undergoing arthroscopic hamstring ACL reconstruction through an accessory medial portal were prospectively studied. Mean age: 26,4 years (15-39) Men: 68% Female: 32%. Average follow-up: 39 months. (36-53) Anteroposterior stability was assessed by using KT-1000 arthrometer. Rotational stability was determined by Lateral Pivot-Shift test. Clinical results were asses by International Knee Documentation Committee (IKDC) and Lysholm scores. Magnetic Resonance Imaging (MRI) was taken at 6 months post-operatively to evaluate graft maturation and incorporation. Results: the average KT-1000 side-to-side difference was 2,09 mm with 92,4% between 1-3 mm, 3,8% between 3-5 mm and 3,8% more than 5 mm. Pivot-Shift test was negative in 86,5% and positive in 13,5% of the patients. IKDC mean score: 89,2; Lysholm mean score: 93,8. Graft integration at MRI: 100% of the patients. 3 patients (5,8%) had an ACL re-rupture (mean 20 months) and 1 patient (1,9%) presented a symptomatic femoral chondral lesion (12 months). Discussion and conclusion: our study shows good and excellent results in anterior and rotational stability as well as IKDC, and Lysholm scores and Graft integration measured by MRI for the anatomic single bundle ACL reconstruction. Re-rupture rate is similar to series with transtibial non-anatomic technique; this is probably due to other factors that do not include the position of the graft. Level of evidence: III. Type of study: Prospective cohort study

Reconstrucción anatómica de ligamento cruzado anterior con banda simple a través del uso de un portal medial accesorio: resultados clínicos e imagenológicos en seguimiento a mediano plazo / Anatomic anterior cruciate ligament reconstruction with single band through an accessory medial portal

Objetivo: Evaluar los resultados clínicos de la reconstrucción anatómica de Ligamento Cruzado Anterior (LCA) con una banda a través de un portal medial accesorio. Material y método: serie prospectiva, 52 pacientes con reconstrucción anatómica de LCA a través de un portal medial accesorio. Edad promedio: 26,4 años (15-39), 68 por ciento hombres, 32 por ciento mujeres. Seguimiento promedio: 39 meses (36-53). Evaluación de estabilidad anteroposterior mediante la prueba artrométrica KT-1000 y estabilidad rotacional con test de Pivot-shift. Resultados clínicos evaluados con scores de Lysholm e International Knee Documentation Committee Score (IKDC). Se solicitó resonancia magnética (RM) 6 meses post-reconstrucción para evaluar la madurez e incorporación del injerto. También se registraron las complicaciones. Resultados: diferencia promedio de KT-1000 entre ambas rodillas: 2,09 mm, 92,4 por ciento de los pacientes entre 1-3 mm, 3,8 por ciento entre 3-5 mm, y 3,8 por ciento con más de 5 mm. Pivot Shift negativo en 86,5 por ciento y presente en 13,5 por ciento de los pacientes. IKDC promedio: 89,2 puntos, Lysholm promedio: 93,8 puntos. Integración del injerto en RM: 100 por ciento de los pacientes. 3 pacientes (5,8 por ciento) presentaron una re-rotura del injerto (20 meses promedio) y 1 paciente (1,9 por ciento) presentó una lesión condral femoral sintomática (12 meses). Discusión y Conclusiones: nuestro estudio muestra buenos y excelentes resultados para la reconstrucción anatómica de LCA con banda simple con respecto a estabilidad anterior y rotacional, scores clínicos e integración del injerto. Nuestra tasa de re-roturas es similar a las tasas descritas en la literatura para reconstrucciones transtibiales, lo que podría explicarse por otros factores involucrados en este proceso independientes de la posición del injerto. Nivel de evidencia: III. Tipo de estudio: Estudio de cohorte prospectivo (AU)

Introduction: The aim of this study was to evaluate the clinical results of anatomic single bundle anterior cruciate ligament (ACL) reconstruction through an accessory medial portal. Methods: prospective case series. Fifty-two patients undergoing arthroscopic hamstring ACL reconstruction through an accessory medial portal were prospectively studied. Mean age: 26,4 years (15-39) Men: 68% Female: 32%. Average follow-up: 39 months. (36-53) Anteroposterior stability was assessed by using KT-1000 arthrometer. Rotational stability was determined by Lateral Pivot-Shift test. Clinical results were asses by International Knee Documentation Committee (IKDC) and Lysholm scores. Magnetic Resonance Imaging (MRI) was taken at 6 months post-operatively to evaluate graft maturation and incorporation. Results: the average KT-1000 side-to-side difference was 2,09 mm with 92,4% between 1-3 mm, 3,8% between 3-5 mm and 3,8% more than 5 mm. Pivot-Shift test was negative in 86,5% and positive in 13,5% of the patients. IKDC mean score: 89,2; Lysholm mean score: 93,8. Graft integration at MRI: 100% of the patients. 3 patients (5,8%) had an ACL re-rupture (mean 20 months) and 1 patient (1,9%) presented a symptomatic femoral chondral lesion (12 months). Discussion and conclusion: our study shows good and excellent results in anterior and rotational stability as well as IKDC, and Lysholm scores and Graft integration measured by MRI for the anatomic single bundle ACL reconstruction. Re-rupture rate is similar to series with transtibial non-anatomic technique; this is probably due to other factors that do not include the position of the graft. Level of evidence: III. Type of study: Prospective cohort study (AU)

Reconstrucción anatómica de ligamento cruzado anterior utilizando técnica de retroconstrucción con FlipCutter / Anatomic reconstruction of anterior cruciate ligament with FlipCutter retroconstruction technique

El posicionamiento anatómico de los túneles en cirugía de ligamento cruzado anterior, ha sido sugerido como una estrategia para reducir la inestabilidad rotacional y por tanto la artrosis futura. Las técnicas más comunes utilizadas para posicionar el túnel femoral son: la técnica transtibial y la técnica de portal anteromedial. Ha sido reportado que un posicionamiento anatómico del túnel femoral es imposible mediante la técnica transtibial, incluso con modificaciones. Por otra parte, la técnica de portal anteromedial si bien logra un posicionamiento más anatómico del túnel femoral, puede resultar en un túnel más corto, además de la posibilidad de causar daño al cartílago articular del cóndilo femoral medial durante el proceso de realización de este; y por último, existe el riesgo de dañar las estructuras neurovasculares al pasar las guías y brocas de medial a lateral. En un esfuerzo por ir mejorando las técnicas quirúrgicas disponibles, se ha desarrollado la técnica de túnel femoral retrogrado o retroconstrucción, la cual lograría posicionar un túnel femoral anatómico evitando las complicaciones de la técnica de portal anteromedial. En este artículo, presentaremos la técnica de Retroconstrucción de LCA con autoinjerto semitendinoso-gracillis, utilizando el instrumental FlipCutterTM (Arthrex Inc, Naples) con método de fijación femoral suspensorio Tight RopeTM (Arthrex Inc, Naples) y fijación tibial con tornillo interferencial BiocompositeTM (Arthrex Inc, Naples).

The anatomical positioning of tunnels in Anterior Cruciate Ligament (ACL) surgery has been suggested as a strategy to reduce rotational instability and osteoarthritis. Usual techniques used to make the femoral tunnel are the transtibial technique and the anteromedial portal technique. It has been reported that it is impossible to make an anatomical femoral tunnel using the transtibial technique, even with variations. Furthemore, the anteromedial portal technique can locate a more anatomical tunnel but has complications like short tunnel, damage to the medial femoral condyle and risks for the lateral neurovascular bundle. In an effort to improve our capacity of positioning an anatomical femoral tunnel with less complications, the retroconstruction technique has been developed. In this article we present the ACL retroconstruction technique using autologous semitendinous-gracillis graft with FlipCutterTM (Arthrex Inc, Naples).

Uso del plasma rico en plaquetas en cirugía ligamentosa de rodilla / Use of platelet rich plasma in knee ligament surgery

Platelet Rich Plasma (PRP) is used in musculoskeletal lesion surgery, including muscle, bone, tendons and ligaments. PRP might accelerate the healing process and the integration of the graft, allowing an earlier return to sports activities of patients. PRP is obtained from autologous blood, which is centrifuged, obtaining platelet and supposedly growth factor concentrations three to five times higher than those of regular blood. The clinical results of studies performed in Chile and elsewhere on PRP use in knee anterior cruciate ligament (ACL) reconstruction have been variable. Therefore, there is not enough evidence to support or deny the usefulness of PRP in ACL reconstructions.

[Use of platelet rich plasma in knee ligament surgery]. / Uso del plasma rico en plaquetas en cirugía ligamentosa de rodilla.

Platelet Rich Plasma (PRP) is used in musculoskeletal lesion surgery, including muscle, bone, tendons and ligaments. PRP might accelerate the healing process and the integration of the graft, allowing an earlier return to sports activities of patients. PRP is obtained from autologous blood, which is centrifuged, obtaining platelet and supposedly growth factor concentrations three to five times higher than those of regular blood. The clinical results of studies performed in Chile and elsewhere on PRP use in knee anterior cruciate ligament (ACL) reconstruction have been variable. Therefore, there is not enough evidence to support or deny the usefulness of PRP in ACL reconstructions.

Reaction times to weak test lights.

Maloney and Wandell [Vision Res. 24, 633-640 (1984)] describe a model of the response of a single visual channel to weak test lights. The initial channel response is a linearly filtered version of the stimulus. The filter output is randomly sampled over time. Each time a sample occurs there is some probability--increasing with the magnitude of the sampled response--that a discrete detection event is generated. Maloney and Wandell derive the statistics of the detection events. In this paper we test the hypothesis that the reaction time responses to the presence of a weak test light are initiated at the first detection event. This permits us to extend the application of the model to lights that are slightly above threshold, but still within the linear operating range of the visual system. We test a parameter-free prediction of the model proposed by maloney and Wandell for lights detected by this statistic. The data are in agreement with the prediction.