Paediatric fibrosarcoma treatment.

Introduction: Soft tissue sarcomas make up 7%-15% of childhood solid tumours. The aetiology of this disease is unknown. It is a fast-growing, painless tumour; histologically similar to adult fibrosarcoma, but having a lesser risk of metastasis and a better prognosis. The treatment is aimed towards localised intervention; complete surgical resection is the appropriate treatment as long as it can be performed. Case report: An 11 years old female was referred for resection of a soft tissue tumour on the right elbow with significant peripheral vascularisation. Tumour resection was scheduled, with the placement of a partial thickness skin graft, and a piece was sent to pathology; a histological type consistent with paediatric fibrosarcoma was obtained with margins less than 1 mm from the lesion. Therefore, the patient was referred to the paediatric oncology unit. Further studies with positron emission tomography were requested, in which no evidence of macroscopic anatomy-metabolic tumour activity was found. Subsequently, treatment was started by paediatric oncology with 2 sessions of chemotherapy and 20 sessions of radiotherapy with sufficient progress; finally, assessment by plastic and reconstructive surgery was performed and an adequate quality of graft was observed, without the need for any other intervention by their service. Conclusion: The involvement of the vascular surgeon in performing the tumour resection permitted the preservation of the best circulation to the extremity, thereby, avoiding amputation. The difficult decision made by the reconstructive surgeon to place a partial thickness graft over the surgical site, and to start radiotherapy/chemotherapy by paediatric oncology, were key to the success in achieving the patient's satisfactory progress.

Susceptibility of Demotispa neivai (Coleoptera: Chrysomelidae) to Beauveria bassiana and Metarhizium anisopliae entomopathogenic fungal isolates.

BACKGROUND: The potential of Beauveria bassiana and Metarhizium anisopliae isolates obtained from naturally infected oil palm pests was evaluated to control Demotispa neivai as an alternative for organophosphate insecticide use in oil palm crops in Latin America. Two B. bassiana (Bb-0018 and Bb-0025) and two M. anisopliae (Ma-0002 and Ma-0003) isolates were tested against D. neivai adults for hydrophobicity, virulence, survival, adhesion to host cuticle, and mortality in semi-field conditions. RESULTS: Concentration-mortality bioassays demonstrate that isolates had lethal effect on D. neivai adults with Bb-0025 [median lethal concentration (LC50 ) = 3.45 × 107 conidia mL-1 ] and Bb-0018 (LC50  = 3.75 × 107 conidia mL-1 ) being the most effective followed by Ma-0003 (LC50  = 3.38 × 108 conidia mL-1 ) and Ma-0002 (5.33 × 108 conidia mL-1 ). Adult survival was 99% without exposure to fungal isolates, decreasing to 21.65% in insects exposed to Ma-0002, 19.41% with Ma-0003, 20.13% with Bb-0018, and 0.17% with Bb-0025. Mortality of D. neivai adults caused by the entomopathogenic fungal isolates was similar in both laboratory and semi-field conditions. Also, vegetative growth of the entomopathogenic fungal isolates was found in infected D. neivai adults in the field. CONCLUSION: Our data suggest that the tested entomopathogenic fungal isolates are effective against D. neivai with potential to be used as biological control agents contributing to the decrease of the use of chemical insecticides to control this oil palm pest. © 2021 Society of Chemical Industry.

Sustainability of the Healthy Municipalities Strategy in Guatemala.

OBJECTIVE: Evaluate the sustainability of the Healthy Municipalities strategy in Guatemala in order to have solid evidence to support decision-making. METHODS: A concurrent mixed-methods study was carried out in five phases: 1) theoretical-conceptual (based on a narrative review of the literature on sustainability, dimensions and categories were proposed for evaluation); 2) empirical (four municipalities were selected for convenience and 29 semi-structured interviews and four focus groups were conducted with key actors to explore sustainability; with this information, a score was assigned to each category and dimension); 3) analytical, by category and dimension (content analysis was performed for qualitative information, and totals and averages were calculated for quantitative information); 4) integrative (qualitative data were integrated into matrices by category and dimension, and quantitative data were supported by qualitative information); and 5) meta-inference (consideration was given to the context and its influence on the results). RESULTS: Ninety-two (92) informants participated. In operational terms, progress was observed in the transfer and use of results, and in rotations in leadership. In the legal and political sphere, accountability and local planning were highlighted. In the economic sphere, progressive investment in health, water and sanitation was emphasized, as well as insufficient investment in social determinants of health. In the social sphere, few mechanisms were observed to promote and strengthen social participation. CONCLUSIONS: In the municipalities that participated in the study, a fair level of sustainability was observed in the Healthy Municipalities strategy.

Sustainability of the Healthy Municipalities Strategy in Guatemala

[ABSTRACT]. Objective. Evaluate the sustainability of the Healthy Municipalities strategy in Guatemala in order to have solid evidence to support decision-making. Methods. A concurrent mixed-methods study was carried out in five phases: 1) theoretical-conceptual (based on a narrative review of the literature on sustainability, dimensions and categories were proposed for evaluation); 2) empirical (four municipalities were selected for convenience and 29 semi-structured interviews and four focus groups were conducted with key actors to explore sustainability; with this information, a score was assigned to each category and dimension); 3) analytical, by category and dimension (content analysis was performed for qualitative information, and totals and averages were calculated for quantitative information); 4) integrative (qualitative data were integrated into matrices by category and dimension, and quantitative data were supported by qualitative information); and 5) meta-inference (consideration was given to the context and its influence on the results). Results. Ninety-two (92) informants participated. In operational terms, progress was observed in the transfer and use of results, and in rotations in leadership. In the legal and political sphere, accountability and local planning were highlighted. In the economic sphere, progressive investment in health, water and sanitation was emphasized, as well as insufficient investment in social determinants of health. In the social sphere, few mechanisms were observed to promote and strengthen social participation. Conclusions. In the municipalities that participated in the study, a fair level of sustainability was observed in the Healthy Municipalities strategy.

[RESUMEN]. Objetivo. Evaluar la sostenibilidad de la estrategia Municipios Saludables en Guatemala, para disponer de evidencia sólida que permita apoyar la toma de decisiones. Métodos. Se realizó un estudio mixto concurrente en cinco fases: 1) teórica-conceptual, se realizó una revisión narrativa de literatura en sostenibilidad, con base en la cual se propusieron dimensiones y categorías para su evaluación; 2) empírica, se seleccionaron por conveniencia cuatro municipios y se realizaron 29 entrevistas semiestructuradas y cuatro grupos focales a actores clave para explorar la sostenibilidad; con esta información, se asignó un puntaje a cada categoría y dimensión; 3) analítica, por categoría y dimensión, se realizó el análisis del contenido para la información cualitativa y sumatorias y promedios para la información cuantitativa; 4) integrativa, los datos cualitativos se integraron en matrices por categoría y dimensión; y los datos cuantitativos se respaldaron con información cualitativa; y 5) metainferencia, se reflexionó sobre el contexto y su influencia en los resultados. Resultados. Participaron 92 informantes. En la dimensión operativa, se destacan avances en la transferencia y el uso de resultados, así como en el relevo de liderazgo. En la dimensión legal y política, se destacaron la rendición de cuentas y los planes locales. En la dimensión económica, se destacó la inversión progresiva en salud, agua y saneamiento, con deficiencia de inversiones en determinantes sociales de la salud. En la dimensión social, se observaron pocos mecanismos para impulsar y fortalecer la participación social. Conclusiones. En los municipios que participaron del estudio se observó un nivel regular de sostenibilidad de la estrategia Municipios Saludables.

[RESUMO]. Objetivo. Avaliar a sustentabilidade da estratégia de Municípios Saudáveis na Guatemala para dispor de evidências sólidas para apoiar o processo decisório. Métodos. Foi realizado um estudo de método misto concorrente em cinco fases: 1) fase teórica-conceitual em que foi feita a revisão narrativa da literatura em sustentabilidade a partir da qual foram propostas dimensões e categorias a serem avaliadas; 2) fase empírica em que foi feita a seleção por conveniência de quatro municípios, com 29 entrevistas semiestruturadas e quatro grupos de discussão com as principais partes interessadas para explorar a sustentabilidade; a partir das informações coletadas, foi dada uma pontuação a cada categoria e dimensão; 3) fase analítica, por categoria e dimensão, em que foi realizada a análise do conteúdo para os dados qualitativos e feito o cálculo de somatórias e médias para os dados quantitativos; 4) fase integrativa em que os dados qualitativos foram integrados em matrizes por categoria e dimensão e os dados quantitativos foram respaldados com a informação qualitativa e 5) metainferência em que foi analisado o contexto e sua influência nos resultados. Resultados. O estudo incluiu 92 participantes. Na dimensão operacional, destacam-se os avanços na transferência e no uso de resultados, bem como a ênfase em liderança. Na dimensão jurídico-política, destacam-se a prestação de contas e os planos locais. Na dimensão econômica, destaca-se o investimento progressivo em saúde, água e saneamento, com investimento inadequado nos determinantes sociais da saúde. Na dimensão social, observam-se poucos mecanismos para incentivar e reforçar a participação social. Conclusões. Foi observado nos municípios participantes do estudo um nível constante de sustentabilidade da estratégia de Municípios Saudáveis.

[Sustainability of the Healthy Municipalities strategy in GuatemalaSustentabilidade da estratégia de Municípios Saudáveis na Guatemala]. / Sostenibilidad de la estrategia Municipios Saludables en Guatemala.

OBJECTIVE: Evaluate the sustainability of the Healthy Municipalities strategy in Guatemala in order to have solid evidence to support decision-making. METHODS: A concurrent mixed-methods study was carried out in five phases: 1) theoretical-conceptual (based on a narrative review of the literature on sustainability, dimensions and categories were proposed for evaluation); (2) empirical (four municipalities were selected for convenience and 29 semi-structured interviews and four focus groups were conducted with key actors to explore sustainability; with this information, a score was assigned to each category and dimension); (3) analytical, by category and dimension (content analysis was performed for qualitative information, and totals and averages were calculated for quantitative information); (4) integrative (qualitative data were integrated into matrices by category and dimension, and quantitative data were supported by qualitative information); and 5) meta-inference (consideration was given to the context and its influence on the results). RESULTS: Ninety-two (92) informants participated. In operational terms, progress was observed in the transfer and use of results, and in rotations in leadership. In the legal and political sphere, accountability and local planning were highlighted. In the economic sphere, progressive investment in health, water and sanitation was emphasized, as well as insufficient investment in social determinants of health. In the social sphere, few mechanisms were observed to promote and strengthen social participation. CONCLUSIONS: In the municipalities that participated in the study, a fair level of sustainability was observed in the Healthy Municipalities strategy.

OBJETIVO: Avaliar a sustentabilidade da estratégia de Municípios Saudáveis na Guatemala para dispor de evidências sólidas para apoiar o processo decisório. MÉTODOS: Foi realizado um estudo de método misto concorrente em cinco fases: 1) fase teórica-conceitual em que foi feita a revisão narrativa da literatura em sustentabilidade a partir da qual foram propostas dimensões e categorias a serem avaliadas; 2) fase empírica em que foi feita a seleção por conveniência de quatro municípios, com 29 entrevistas semiestruturadas e quatro grupos de discussão com as principais partes interessadas para explorar a sustentabilidade; a partir das informações coletadas, foi dada uma pontuação a cada categoria e dimensão; 3) fase analítica, por categoria e dimensão, em que foi realizada a análise do conteúdo para os dados qualitativos e feito o cálculo de somatórias e médias para os dados quantitativos; 4) fase integrativa em que os dados qualitativos foram integrados em matrizes por categoria e dimensão e os dados quantitativos foram respaldados com a informação qualitativa e 5) metainferência em que foi analisado o contexto e sua influência nos resultados. RESULTADOS: O estudo incluiu 92 participantes. Na dimensão operacional, destacam-se os avanços na transferência e no uso de resultados, bem como a ênfase em liderança. Na dimensão jurídico-política, destacam-se a prestação de contas e os planos locais. Na dimensão econômica, destaca-se o investimento progressivo em saúde, água e saneamento, com investimento inadequado nos determinantes sociais da saúde. Na dimensão social, observam-se poucos mecanismos para incentivar e reforçar a participação social. CONCLUSÕES: Foi observado nos municípios participantes do estudo um nível constante de sustentabilidade da estratégia de Municípios Saudáveis.

Sostenibilidad de la estrategia Municipios Saludables en Guatemala

[RESUMEN]. Objetivo. Evaluar la sostenibilidad de la estrategia Municipios Saludables en Guatemala, para disponer de evidencia sólida que permita apoyar la toma de decisiones. Métodos. Se realizó un estudio mixto concurrente en cinco fases: 1) teórica-conceptual, se realizó una revisión narrativa de literatura en sostenibilidad, con base en la cual se propusieron dimensiones y categorías para su evaluación; 2) empírica, se seleccionaron por conveniencia cuatro municipios y se realizaron 29 entrevistas semiestructuradas y cuatro grupos focales a actores clave para explorar la sostenibilidad; con esta información, se asignó un puntaje a cada categoría y dimensión; 3) analítica, por categoría y dimensión, se realizó el análisis del contenido para la información cualitativa y sumatorias y promedios para la información cuantitativa; 4) integrativa, los datos cualitativos se integraron en matrices por categoría y dimensión; y los datos cuantitativos se respaldaron con información cualitativa; y 5) metainferencia, se reflexionó sobre el contexto y su influencia en los resultados. Resultados. Participaron 92 informantes. En la dimensión operativa, se destacan avances en la transferencia y el uso de resultados, así como en el relevo de liderazgo. En la dimensión legal y política, se destacaron la rendición de cuentas y los planes locales. En la dimensión económica, se destacó la inversión progresiva en salud, agua y saneamiento, con deficiencia de inversiones en determinantes sociales de la salud. En la dimensión social, se observaron pocos mecanismos para impulsar y fortalecer la participación social. Conclusiones. En los municipios que participaron del estudio se observó un nivel regular de sostenibilidad de la estrategia Municipios Saludables.

[ABSTRACT]. Objective. Evaluate the sustainability of the Healthy Municipalities strategy in Guatemala in order to have solid evidence to support decision-making. Methods. A concurrent mixed-methods study was carried out in five phases: 1) theoretical-conceptual (based on a narrative review of the literature on sustainability, dimensions and categories were proposed for evaluation); (2) empirical (four municipalities were selected for convenience and 29 semi-structured interviews and four focus groups were conducted with key actors to explore sustainability; with this information, a score was assigned to each category and dimension); (3) analytical, by category and dimension (content analysis was performed for qualitative information, and totals and averages were calculated for quantitative information); (4) integrative (qualitative data were integrated into matrices by category and dimension, and quantitative data were supported by qualitative information); and 5) meta-inference (consideration was given to the context and its influence on the results). Results. Ninety-two (92) informants participated. In operational terms, progress was observed in the transfer and use of results, and in rotations in leadership. In the legal and political sphere, accountability and local planning were highlighted. In the economic sphere, progressive investment in health, water and sanitation was emphasized, as well as insufficient investment in social determinants of health. In the social sphere, few mechanisms were observed to promote and strengthen social participation. Conclusions. In the municipalities that participated in the study, a fair level of sustainability was observed in the Healthy Municipalities strategy.

[RESUMO]. Objetivo. Avaliar a sustentabilidade da estratégia de Municípios Saudáveis na Guatemala para dispor de evidências sólidas para apoiar o processo decisório. Métodos. Foi realizado um estudo de método misto concorrente em cinco fases: 1) fase teórica-conceitual em que foi feita a revisão narrativa da literatura em sustentabilidade a partir da qual foram propostas dimensões e categorias a serem avaliadas; 2) fase empírica em que foi feita a seleção por conveniência de quatro municípios, com 29 entrevistas semiestruturadas e quatro grupos de discussão com as principais partes interessadas para explorar a sustentabilidade; a partir das informações coletadas, foi dada uma pontuação a cada categoria e dimensão; 3) fase analítica, por categoria e dimensão, em que foi realizada a análise do conteúdo para os dados qualitativos e feito o cálculo de somatórias e médias para os dados quantitativos; 4) fase integrativa em que os dados qualitativos foram integrados em matrizes por categoria e dimensão e os dados quantitativos foram respaldados com a informação qualitativa e 5) metainferência em que foi analisado o contexto e sua influência nos resultados. Resultados. O estudo incluiu 92 participantes. Na dimensão operacional, destacam-se os avanços na transferência e no uso de resultados, bem como a ênfase em liderança. Na dimensão jurídico-política, destacam-se a prestação de contas e os planos locais. Na dimensão econômica, destaca-se o investimento progressivo em saúde, água e saneamento, com investimento inadequado nos determinantes sociais da saúde. Na dimensão social, observam-se poucos mecanismos para incentivar e reforçar a participação social. Conclusões. Foi observado nos municípios participantes do estudo um nível constante de sustentabilidade da estratégia de Municípios Saudáveis.

Análisis de convenios, contratos y acuerdos del Centro de Investigaciones y Estudios de la Salud (CIES-UNAN Managua), período 2006-2018 / Analysis of agreements, contracts and agreements of the Center for Health Research and Studies (CIES-UNAN Managua), period 2006-2018

Estudio descriptivo. El presente análisis recayó sobre ciento cincuenta y cuatro documentos, entre convenios, contratos y acuerdos del CIES-UNAN Managua, con tres ejes descriptores; el proceso de firma de los mismos, el aspecto técnico y el administrativo. Se contó con la autorización de las autoridades del CIES UNAN-Managua para la realización de este estudio. La confianza en la Institución CIES, reflejada en su prestigio a través de los Graduados y de las iniciativas que, para responder a las necesidades de los Sistemas de Salud de Nicaragua y la Región, ha lanzado con otros socios a través de su historia. Esto a través de las características institucionales que define para el CIES la Ley 103, reforma de la ley 89, la cual faculta a esta firma de Convenio de forma directa por el CIES-UNAN Managua. Más recientemente, a partir de la segunda década del siglo XXI, la UNAN Managua ha venido centralizando esta facultad, lo cual ha constituido una fortaleza para el CIES-UNAN Managua al ser incorporado en las estrategias de desarrollo institucionales de esta Alma Máter. El CIES tiene asociados en todas partes del mundo priorizando la educación y la salud, relacionándose por igual con ONGs, instituciones públicas, organismos internacionales, instituciones privadas entre otras, abiertas a colaborar por medio de la firma de convenios para el logro de sus objetivos en beneficio de la población

Perfil epidemiológico de neoplasias epiteliales de glándulas salivales / Epithelial tumors of salivary glands: review of 286 pathology reports

Background:: Epithelial tumors of the salivary glands, including benign tumors and aggressive malignancies with different prognoses, are uncommon. Aim: To describe the frequency and distribution of salivary gland tumors according to age, gender and anatomical location. Material and Methods: Review of pathological reports of salivary gland tumors of a Pathology laboratory at a clinical hospital from 2006 to 2016. Results: Five hundred ninety salivary gland biopsies were reviewed. Of these, 286 (49%) were primary epithelial tumors of the salivary glands. Two hundred thirty (80%) were benign and 56 (20%) were malignant tumors. Regarding location, 274 (96%) were in the major salivary glands, and 12 (4%) in the minor salivary glands. The most common histological types were pleomorphic adenoma for benign tumors in 172 cases, followed by papillary cystadenoma lymphomatosum in 33 cases. Mucoepidermoid carcinoma was the most common malignant tumor in 14 cases. Conclusions: These results are similar to reports from abroad, however more studies are necessary to be able to establish a more representative and updated analysis.

Can overcompensation increase crop production?

The two most pressing challenges to agriculture worldwide are feeding a rapidly growing human population and developing more sustainable agricultural practices that do not threaten human and ecosystem health. We address these challenges through research in plant-herbivore interactions, specifically overcompensatory responses in potato to herbivore damage. While herbivory is usually detrimental to most crops, some potato cultivars can overcompensate and increase crop productivity up to two-fold in response to herbivore damage. However, biotic and abiotic factors are known to influence compensatory responses. Here we tested if compensatory plant responses to herbivory increase productivity of potatoes under field conditions along gradients of altitude and landscape simplification in 15 different farms. Our results suggest that compensatory plant responses could double the mean productivity of a potato farm in relation to the productivity of undamaged plants. The compensatory response is best predicted by pest pressure on a farm with potato plants having the maximum productivity when 10% of the tubers are damaged and decreasing in productivity as pest pressure increases. To a lesser extent an interaction between altitude and landscape simplification did affect the compensatory response, suggesting that abiotic factors play an important role in compensation. Our results suggest that overcompensation-based management practices could be used to maximize yields on working potato farms. Further research is required to determine action thresholds (i.e. the damage levels at which pest control needs to be enacted to maximize yields and minimize insecticide use) to develop more sustainable ways of increasing yields in the future.

[Epithelial tumors of salivary glands. Review of 286 pathology reports]. / Perfil epidemiológico de neoplasias epiteliales de glándulas salivales.

BACKGROUND: Epithelial tumors of the salivary glands, including benign tumors and aggressive malignancies with different prognoses, are uncommon. AIM: To describe the frequency and distribution of salivary gland tumors according to age, gender and anatomical location. MATERIAL AND METHODS: Review of pathological reports of salivary gland tumors of a Pathology laboratory at a clinical hospital from 2006 to 2016. RESULTS: Five hundred ninety salivary gland biopsies were reviewed. Of these, 286 (49%) were primary epithelial tumors of the salivary glands. Two hundred thirty (80%) were benign and 56 (20%) were malignant tumors. Regarding location, 274 (96%) were in the major salivary glands, and 12 (4%) in the minor salivary glands. The most common histological types were pleomorphic adenoma for benign tumors in 172 cases, followed by papillary cystadenoma lymphomatosum in 33 cases. Mucoepidermoid carcinoma was the most common malignant tumor in 14 cases. CONCLUSIONS: These results are similar to reports from abroad, however more studies are necessary to be able to establish a more representative and updated analysis.

Surgical Site Infections Rates in More Than 13,000 Surgical Procedures in Three Cities in Peru: Findings of the International Nosocomial Infection Control Consortium.

BACKGROUND: Surgical site infections (SSIs) are a threat to patient safety. However, there are not available data on SSI rates stratified by surgical procedure (SP) in Peru. METHODS: From January 2005 to December 2010, a cohort prospective surveillance study on SSIs was conducted by the International Nosocomial Infection Control Consortium (INICC) in four hospitals in three cities of Peru. Data were recorded from hospitalized patients using the U.S. Centers for Disease Control and Prevention-National Healthcare Safety Network (CDC-NHSN) methods and definitions for SSI. Surgical procedures (SPs) were classified into 4 types, according to ICD-9 criteria. RESULTS: We recorded 352 SSIs, associated to 13,904 SPs (2.5%; CI, 2.3-2.8) SSI rates per type of SP were the following for this study's Peruvian hospitals, compared with rates of the INICC and CDC-NHSN reports, respectively: 2.9% for appendix surgery (vs. 2.9% vs. 1.4%); 2.8% for gallbladder surgery (vs. 2.5% vs. 0.6%); 2.2% for cesarean section (vs. 0.7% vs. 1.8%); 2.8% for vaginal hysterectomy (vs. 2.0% vs. 0.9%). CONCLUSIONS: Our SSIs rates were higher in all of the four analyzed types of SPs compared with CDC-NHSN, whereas compared with INICC, most rates were similar. This study represents an important advance in the knowledge of SSI epidemiology in Peru that will allow us to introduce targeted interventions.

Exposición ocupacional y ambiental al arsénico: actualización bibliográfica para investigación científica / Occupational and environmental exposure to arsenic: bibliographical update for research

El arsénico (As) es un metaloide presente en minerales complejos que contienen cobre, plomo y otros; en el trabajador causa arsenicismo ocupacional y la principal exposición ocurre en metalurgia del cobre. Sus compuestos trivalentes tienen tendencia acumulativa e ingresan por las vías respiratoria, digestiva o cutánea y se transforman en los ácidos dimetilarsínico y metilarsónico. En la mitocondria, con el azufre de los grupos mercapto forma enlaces covalentes y desacopla la fosforilación oxidativa, sugiriendo una acción inhibitoria no hidrolítica a ese nivel. Es cancerígeno para varios órganos. Se excreta por orina, heces y piel. Los peces y mariscos contienen arsénico orgánico. En sujetos no expuestos, dependiendo de la dieta, el As inorgánico en orina es < 5 ug/L. El índice de exposición biológica para trabajadores medido al final de la semana laboral es 35 µg/g creatinina y el valor límite umbral para ambientes de trabajo es 0,01mg/m³. La arsina es el compuesto arsenical más tóxico. El arsénico contenido en el agua de ciertas regiones produce la enfermedad ambiental llamada hidroarsenicismo crónico regional endémico.

Arsenic is a metalloid present in ores containing copper and causes a severe occupational disease. The main occupational exposure occurs in copper metallurgy. It enters the human body by the respiratory, digestive and skin tracts. It is transformed into dimethylarsinic and methylarsonic acids that are excreted by urine, feces or skin. Its trivalent compounds are cumulative and might cause cancer in several organs. Arsenic binds with a covalent link to mercapto sulfur groups and it uncouples oxidative phosphorylation, suggesting a non-hydrolytic inhibitory action in mitochondria. Some fish and shellfish contain high amounts of organic arsenic. In subjects unexposed, in agreement to the diet inorganic arsenic is <5 ug/g creatinine. The biologic exposure index in workers is 35 ug/g creatinine measured at the end of a work week. The threshold level value in work environment is 0.01mg/m³. Arsine is the most toxic arsenical compound. Endemic regional hydroarsenicism is an environmental disease caused by water arsenic contents in some regions.

Silicosis / Silicosis

La silicosis es una neumoconiosis producida por inhalación repetida de polvo de sílice, caracterizada por fibrosis pulmonar y acompañada de problemas bronquíticos. Es factor predisponente para cáncer pulmonar y determina incapacidades laborales temporales o permanentes. De acuerdo a su forma de presentación, la silicosis puede ser clásica, aguda, complicada o acelerada. El Perú es un país minero con más de 197 mil trabajadores directos en esta actividad considerada de riesgo alto para contraer silicosis. El examen clínico, los antecedentes laborales, la radiografía de pulmones y la espirometría son la base del diagnóstico. Para la silicosis no existe tratamiento, por lo que la prevención es la única forma conocida de evitarla. La principal medida preventiva es la educación del trabajador y del empleador para hacerles conocer el riesgo de exposición a polvo de sílice y las medidas de protección colectiva y personal.

Silicosis is a pneumoconiosis caused by repeated inhalation of silica dust, characterized by pulmonary fibrosis and a bronchitis component. It is predisposing factor for lung cancer and cause of temporary or permanent work disability. According to its presentation it may be classical, acute, complicated or accelerated. Peru is a mining country with more than 197 000 direct workers in this activity considered at high risk for developing silicosis. Clinical examination, labor history, lung X-rays and spirometry are basic in diagnosis. There is no treatment for silicosis. Prevention is the only known way to avoid it. In addition to collective and personal protection, main preventive action is education of workers and employers on risk of exposure to silica dust.

Servicios de salud ocupacional / Occupational health services

Los Servicios de Salud Ocupacional tienen por misión prevenir las enfermedades causadas o relacionadas con el trabajo desarrollando programas preventivo-promocionales de salud, cuya base son los exámenes ocupacionales. La vigilancia de salud con estos exámenes es la herramienta de mayor uso en prevención y control de las enfermedades laborales. Su manejo técnico por el médico ocupacionista permite reconocer daño a la salud del trabajador en las primeras etapas de una enfermedad ocupacional. Gestionar la salud en el trabajo mediante exámenes periódicos deviene en la acción esencial de los Servicios de Salud Ocupacional. Es responsabilidad de la Empresa conformar y mantener servicios de salud laboral dirigidos por un médico especializado en medicina del trabajo e integrados por un equipo que incluya enfermería ocupacional, higiene industrial, personal técnico y especialidades afines de salud.

Medical surveillance via occupational medical examinations is the most widely tool used in prevention and control of job-related diseases. Its management by the occupational physician allows recognition of the occupational disease. By developing programs of preventive-promotional health and occupational examinations the Occupational Health Services make possible early recognition of labor health problems. Their goal is to prevent work-related diseases. Companies must establish and maintain labor health services integrated by specialized physicians in occupational medicine as head of a team that includes occupational nurses, industrial hygiene, and other technicians specialized in labor health-related fields.

Mejora de los indicadores biológicos de exposición al mercurio en trabajadores de una refinería de oro / Improvement of workers' biological indicators exposed to mercury at a gold refinery

Introducción: La exposición al mercurio asociada a malas prácticas de higiene laboral favorece el desarrollo de la intoxicación ocupacional denominada mercurialismo. Para verificar el impacto que la mejoría de los niveles ambientales de mercurio tendría en trabajadores de la refinería en una empresa aurífera peruana, se elaboró un programa de reingeniería para el control de la exposición que abarca aspectos de salud e higiene laboral y participación activa de la jefatura operativa. Objetivos: Estudiar en trabajadores de una refinería aurífera las variaciones de indicadores de exposición a mercurio al mejorar la calidad del ambiental laboral. Diseño: Estudio prospectivo y descriptivo. Lugar de estudio: Servicio de Salud Ocupacional de una empresa minera aurífera en el Perú. Participantes: Trabajadores de la refinería de oro. Intervenciones: Se modificó la metodología del examen médico y de la evaluación del ambiente laboral de 100 trabajadores de la refinería de oro, durante el periodo 2003-2007, además de mejorar las condiciones de trabajo. Luego, se cuantificó semestralmente los límites ambientales del tóxico y los indicadores de exposición. Se analizó estadísticamente la variación de los valores medios de los indicadores biológicos respecto a la variación del tóxico en el ambiente de trabajo. Principales medidas de resultados: Mejora de los indicadores ambientales y biológicos. Resultados: Los valores medios de los indicadores ambientales mejoraron cada año, al igual que los indicadores biológicos del universo estudiado. El mercurio ambiental en 2 003 fue 6,3 mg/m3 y, en 2 007, 0,03, valor de p < 0,001. El indicador mercurio urinario en 2003 fue 11,9 ug/L y, en 2007, 2,3 con p < 0,01. Conclusiones: En el grupo estudiado, la disminución del tóxico en el ambiente de labor determinó la mejora significativa de los indicadores biológicos de exposición al mercurio en el trabajador.

Background: Occupational exposure to mercury is associated to mercurialism, a characteristic occupational poisoning. To verify impact of environmental mercury levels improvement would have in gold's refinery workers of a Peruvian auriferous company, we carried out a reengineering program for exposure control. This program included health and hygiene occupational aspects and operation's management active participation. Objective: To study in gold refinery workers variations in indicators of exposure to mercury with environment labor quality improvement. Design: Prospective and descriptive study. Place of study: Occupational Health Service in a Peruvian mining company. Participants: Workers of gold refinery. Interventions: Modification of physician examination methodology, hygienic evaluation and improved conditions of the labor environment. Every six months we quantified the environmental limits of both toxic and biological exposure indicators. Then variation of exposure biological indices versus variation of environmental limits was analyzed. Main outcome measures: Environmental and biological indicators. Results: Environmental indicators values improved every year, as well as workers biological indicators. Environmental mercury decreased from 6.3 mg/m3 in 2003 to 0.03 at the end of 2007, p < 0.001. Urinary mercury decreased from 11.9 ug/L in 2003 to 2.3 in 2007, p < 0.01. Conclusions: In the group studied workers' toxic levels decreased with improvement of the environment indicator.

Exposición toxicológica en las grandes alturas: ¿es necesario corregir los valores límite umbral de exposición de tóxicos? / Toxicology exposure at high altitude: is it necessary to correct toxic exposure threshold limit values?

El nativo de altura posee variantes anatomofisiológicas en el sistema respiratorio. Las de mayor significado son los aumentos de amplitud torácica, ventilación pulmonar, difusión alveolo/capilar y del contenido arterial de oxígeno. En salud ocupacional, para controlar los riesgos del trabajo se aplica valores límites de exposición desarrollados a nivel del mar y para poblaciones con características físicas y laborales diferentes a las de altura. Fisiológicamente, un trabajo seguro en la altura se caracteriza porque el organismo no demanda mayor energía que a nivel del mar para realizarlo, a pesar de la caída de la presión barométrica y esto es así hasta los 2 500 msnm. De acuerdo a esta premisa, cuando por el nivel de altitud el organismo compensa la baja presión barométrica con aumento de la ventilación pulmonar, es necesario corregir los límites de exposición. Aún no se ha establecido límites de exposición seguros en la altura, lo que implica continuar investigando.

In occupational health to control risk magnitude we apply threshold limit values. Man at high altitude has anatomical-physiological variants in his respiratory system; most important are increases in thoracic capacity, pulmonary ventilation, alveolar/capillary diffusion, and arterial oxygen content. Physiological safe work at high altitude consists in the organism not using extra energy to compensate barometric pressure fall. In respiratory occupational toxicology we must initiate correction when ventilatory response to hypobaric hypoxia becomes unsafe and this occurs at 8 000 feet above sea level. Accordingly we should correct exposure limits value applying to work at high altitude. In order to establish safe parameters of toxicological exposition at high altitude it is necessary to investigate these aspects in high altitude workers.

Toxicidad del cianuro: investigación bibliográfica de sus efectos en animales y en el hombre: [revisión] / Cyanide toxicity: bibliography research of its effects in animals and ma: [review]

Se llama cianuro al cianuro en sí, al cianuro de hidrógeno y a sus sales. Los cianuros existen en forma natural e industrialmente se les obtiene como sales. Aún a dosis bajas son compuestos letales en tiempo mínimo de exposición. El sistema nervioso es su órgano blanco primario. Luego de ingestión, inhalación o contacto se presentan efectos neurotóxicos graves y mortales en humanos y animales. La exposición ocupacional produce alteraciones tiroideas, cefalea, vértigo, vómito, náuseas, dermatitis y exposiciones altas; a corto tiempo, terminan en paro respiratorio y muerte. Algunos compuestos de cianuro en microcantidades son indispensables para la vida. Respecto a su poder carcinógeno, al cianuro se le considera en el grupo D de los æno clasificables como carcinógenos humanosÆ. Para aplicar mejor las medidas preventivas en el trabajo con cianuros, y en salud pública, es necesario conocer satisfactoriamente su acción tóxica sobre los animales y el hombre.

Cyanide, hydrogen cyanide and its salts are called cyanide. They exist in natural form and are obtained as salts in industry. At low doses they are lethal in mínimum exposure time. The nervous system is its primary target organ. After ingestion, contact or inhalation, serious neurotoxic effects appear in humans and animals. Occupational exposure can produce headache, vertigo, vomiting, nausea, thyroid gland alterations, and dermatitis. At high doses and in short time, cyanide exposure can end in death. In very low amounts some cyanide compounds are indispensable for life. Cyanide is located in group D ônot classifiable as human carcinogenõ. In order to apply preventive measures when working with cyanides and in public health, it is necessary to acknowledge cyanide toxic effects on men and animals.

La teoría del conocimiento en investigación científica: una visión actual / Knowledge's theory in scientific research: a current scope

El conocimiento es el acto consciente e intencional para aprehender las cualidades del objeto y primariamente es referido al sujeto, el Quién conoce, pero lo es también a la cosa que es su objeto, el Qué se conoce. Su desarrollo ha ido acorde con la evolución del pensamiento humano. La epistemología estudia el conocimiento y ambos son los elementos básicos de la investigación científica, la que se inicia al plantear una hipótesis para luego tratarla con modelos matemáticos de comprobación y finalizar estableciendo conclusiones valederas y reproducibles. La investigación científica ha devenido en un proceso aceptado y validado para solucionar interrogantes o hechos nuevos encaminados a conocer los principios y leyes que sustentan al hombre y su mundo; posee sistemas propios basados en el método de hipótesis-deducción/inducción complementados con cálculos estadísticos y de probabilidades. El buen manejo de la teoría del conocimiento en investigación científica permite respuestas correctas y técnicas a cualquier hipótesis, razón por la que el investigador científico debería conocer su teoría y evolución.

Knowledge is a conscious, intentional and individual act to learn object's qualities and is firstly referred to who knows but also to the object thing what is known. Its development has been close to human thought evolution. Epistemology, the science that studies knowledge, is based in scientific research that begins with a hypothesis exposition and develops afterwards with mathematical models to have verifiable and valid conclusions. Scientific research is an accepted and validated process for new facts or questions solutions guided to recognize principles and laws that sustain man's life in the world. It owns methods based on hypothesis deduction/induction complemented with statistics and calculation probabilities. Scientific researchers should know its theory and evolution because they are indispensable tools in research and its good handling will allow technical and suitable answers for any hypothesis.