New Benzotrithiophene-Based Molecules as Organic P-Type Semiconductor for Small-Molecule Organic Solar Cells.

A new benzotrithiophene-based small molecule, namely 2,5,8-Tris[5-(2,2-dicyanovinyl)-2-thienyl]-benzo[1,2-b:3,4-b':6,5-b″]-trithiophene (DCVT-BTT), was successfully synthesized and subsequently characterized. This compound was found to present an intense absorption band at a wavelength position of ∼544 nm and displayed potentially relevant optoelectronic properties for photovoltaic devices. Theoretical studies demonstrated an interesting behavior of charge transport as electron donor (hole-transporting) active material for heterojunction cells. A preliminary study of small-molecule organic solar cells based on DCVT-BTT (as the P-type organic semiconductor) and phenyl-C61-butyric acid methyl ester (as the N-type organic semiconductor) exhibited a power conversion efficiency of 2.04% at a donor: acceptor weight ratio of 1:1.

Morphological characteristics of the left gastric, common hepatic and splenic arteries. A descriptive study in human cadaveric specimens.

OBJECTIVE: to evaluate the morphology of the branches of celiac trunk (CT), left gastric (LGA), common hepatic (CHA), and splenic (SA) arteries in cadaveric specimens from a sample of a Colombian population. METHODS: descriptive cross-sectional study of 26 blocks from the abdominal upper segment of human cadavers who underwent forensic autopsies at the Instituto de Medicina Legal at Bucaramanga, Colombia. The vascular beds of the celiac trunk were, subsequently, perfused with a semi-synthetic resin. RESULTS: the diameters of LGA, CHA, and SA were 3.6±0.8mm, 5,2±1.2mm, and 5.9±1.0mm, respectively. Statistically, LGA and SA were different (p=<0.001). SA followed a linear trajectory in 8 (31%) samples, slightly tortuous in 4 (15%), and tortuous in 14 (54%). The tortuosity index was 1.25±0.18. Of the branches of CHA, the proper hepatic artery (PHA) had 4.8±1.2mm in diameter and 18.8±9.1mm in length, whereas the gastroduodenal artery (GDdA) had 4.1±0.8mm. In 2 cases (7.7%), an accessory hepatic artery from the LGA was found to supply perfusion to the left hepatic lobe. Finally, in 2 cases (7.7%) the SA came independently from the abdominal aorta. CONCLUSION: the observed emergence incidence of the CT branches from the same level as reported in the literature is lower. The characterization, along with their variants, of LGA, CHA, and SA must be considered in surgical procedures in the upper abdominal segment, to avoid iatrogenic complications.

Morphological characteristics of the left gastric, common hepatic and splenic arteries. A descriptive study in human cadaveric specimens / Características morfológicas das artérias gástricas esquerda, hepática comum e esplênica. Um estudo descritivo em espécimes cadavéricos humanos

ABSTRACT Objective: to evaluate the morphology of the branches of celiac trunk (CT), left gastric (LGA), common hepatic (CHA), and splenic (SA) arteries in cadaveric specimens from a sample of a Colombian population. Methods: descriptive cross-sectional study of 26 blocks from the abdominal upper segment of human cadavers who underwent forensic autopsies at the Instituto de Medicina Legal at Bucaramanga, Colombia. The vascular beds of the celiac trunk were, subsequently, perfused with a semi-synthetic resin. Results: the diameters of LGA, CHA, and SA were 3.6±0.8mm, 5,2±1.2mm, and 5.9±1.0mm, respectively. Statistically, LGA and SA were different (p=<0.001). SA followed a linear trajectory in 8 (31%) samples, slightly tortuous in 4 (15%), and tortuous in 14 (54%). The tortuosity index was 1.25±0.18. Of the branches of CHA, the proper hepatic artery (PHA) had 4.8±1.2mm in diameter and 18.8±9.1mm in length, whereas the gastroduodenal artery (GDdA) had 4.1±0.8mm. In 2 cases (7.7%), an accessory hepatic artery from the LGA was found to supply perfusion to the left hepatic lobe. Finally, in 2 cases (7.7%) the SA came independently from the abdominal aorta. Conclusion: the observed emergence incidence of the CT branches from the same level as reported in the literature is lower. The characterization, along with their variants, of LGA, CHA, and SA must be considered in surgical procedures in the upper abdominal segment, to avoid iatrogenic complications.

RESUMO Objetivo: avaliar a morfologia dos ramos das artérias do tronco celíaco (CT), gástrica esquerda (LGA), hepática comum (HC) e esplênica (SA) em espécimes cadavéricos de uma amostra de uma população colombiana. Métodos: estudo transversal descritivo de 26 blocos do segmento superior abdominal de cadáveres humanos submetidos a necropsias forenses no Instituto de Medicina Legal de Bucaramanga, Colômbia. Os leitos vasculares do tronco celíaco foram, posteriormente, perfundidos com resina semissintética. Resultados: os diâmetros de LGA, CHA e SA foram 3,6±0,8mm, 5,2±1,2mm e 5,9±1,0mm, respectivamente. Estatisticamente, LGA e SA foram diferentes (p=<0,001). A SA seguiu uma trajetória linear em 8 (31%) amostras, levemente tortuosa em 4 (15%) e tortuosa em 14 (54%). O índice de tortuosidade foi de 1,25±0,18. Dos ramos do ACS, a artéria hepática própria (APH) tinha 4,8±1,2mm de diâmetro e 18,8±9,1mm de comprimento, enquanto a artéria gastroduodenal (GDdA) tinha 4,1±0,8mm. Em 2 casos (7,7%), uma artéria hepática acessória do GIG foi encontrada para fornecer perfusão ao lobo hepático esquerdo. Finalmente, em 2 casos (7,7%) a SA veio independentemente da aorta abdominal. Conclusão: a incidência observada de emergência dos ramos de TC do mesmo nível relatado na literatura é menor. A caracterização, juntamente com suas variantes, de LGA, CHA e SA deve ser considerada em procedimentos cirúrgicos no segmento abdominal superior, para evitar complicações iatrogênicas.

[Economic, social, and health determinants that influence exclusive breastfeeding in Colombia]. / Determinantes económicos, sociales y de salud que inciden en la lactancia materna exclusiva en Colombia.

Exclusive breastfeeding (EBF) is an important practice that offers many benefits, such as nutritional support, prevention of infectious and chronic diseases, and assistance in psychosocial and cognitive development. This study aims to identify the determinants associated with EBF abandonment in 1,527 children under six months of age, based on information collected by the Colombian National Survey of Nutritional Status and the Colombian National Demographic and Health Survey, 2010. This is an observational cross-sectional cohort study, in which a hierarchical Poisson regression model with robust variance was applied; considering in the first level the factors associated with the mother and child and, in the second level, the information of 32 departments and Bogotá. We noticed a high rate abandonment of EBF (57.6%) and its variation between departments. The factors associated with a longer time of EBF were higher maternal schooling level, having a partner, knowledge in breastfeeding, belonging to a lower level of income, living in the eastern region, having delivery assisted by qualified team, and low birth weight. According to the variance partition coefficient (VPC), 3.2% of the probability of abandonment of EBF may be related to factors within the departmental scope. The median odds ratio (MOR) indicates that the individual risk of abandoning EBF of a child would increase by 47% if the child moved from a department with a low prevalence of abandonment to a department with high prevalence. This study allows a better understanding of the abandonment of EBF from its determinants, providing evidence to implement more effective interventions for child nutrition.

La lactancia materna exclusiva (LME) es fundamental. Algunos beneficios son su aporte nutricional, prevención de enfermedades infecciosas y crónicas, el desarrollo psicosocial y cognitivo. El objetivo del estudio fue establecer los determinantes asociados al abandono de la LME en 1.527 menores de seis meses, a partir de la información recolectada en la Encuesta Nacional de Situación Nutricional en Colombia y en la Encuesta Nacional de Demografía y Salud, 2010. Es un estudio observacional de corte transversal en el que se aplicó un modelo jerárquico de regresión de Poisson con varianza robusta, tomando como primer nivel factores asociados a la madre y al niño, y como segundo nivel, la información de 32 departamentos y Bogotá. Se resalta el elevado abandono de la LME (57,6%) y su variación entre departamentos. La mayor escolaridad de la madre, tener un compañero, educación en lactancia, pertenecer al quintil de riqueza más pobre, residir en la región oriental, contar con un parto atendido por personal calificado y el bajo peso al nacer favorecen el tiempo de LME. Según el coeficiente de partición de varianza (CPV), un 3,2% de la probabilidad de abandono de la LME podría deberse a factores del nivel departamental. La mediana del odds ratio (MOR) indicó que el riesgo individual de abandono de LME para un niño se incrementa en 47% si este cambiara de residencia de un departamento de baja prevalencia de abandono a uno de alta. Este estudio contribuye a una mayor comprensión del abandono de la LME desde los determinantes, aportando evidencia para el diseño de intervenciones más costo-efectivas en alimentación infantil.

O aleitamento materno exclusivo (AME) é importante. Essa prática oferece muitos benefícios, como aporte nutricional, prevenção de doenças infecciosas e crônicas, e auxílio no desenvolvimento psicossocial e cognitivo. Este estudo teve como objetivo identificar os determinantes associados ao abandono do AME em 1.527 crianças menores de seis meses, com base nas informações coletadas na Pesquisa Colombiana de Situação Alimentar e Nutricional e na Pesquisa Nacional de Demografia e Saúde da Colômbia, 2010. Trata-se de um estudo observacional, de coorte transversal, no qual foi aplicado um modelo hierárquico de regressão de Poisson com variância robusta, considerando no primeiro nível os fatores associados à mãe e à criança e no segundo nível as informações de 32 departamentos e de Bogotá. Destaca-se o elevado abandono do AME (57,6%) e sua variação entre os departamentos. Estiveram associados ao maior tempo de AME maior escolaridade da mãe, ter companheiro, conhecimento em amamentação, pertencer ao baixo nível de renda, morar na região oriental, ter parto assistido por equipe qualificada e baixo peso ao nascer. De acordo com o coeficiente de partição de variância (CPV), 3,2% da probabilidade de abandono do AME pode estar relacionada a fatores no âmbito departamental. A mediana do odds ratio (MOR) aponta que o risco individual de abandono do AME para uma criança aumentaria em 47% se a criança mudasse de um departamento com baixa prevalência de abandono para um departamento com alta prevalência. Este estudo possibilita uma melhor compreensão do abandono do AME a partir de seus determinantes, fornecendo evidências para implementar intervenções mais efetivas para a alimentação infantil.

Concordancia entre criterios de clasificación nutricional en adultos mayores, Colombia / Accordance between different nutritional classification criteria in older adults, Colombia

Introducción: El envejecimiento es un proceso irreversible que genera aumento permanente de la población de 60 o más años. Esta población vulnerable, vive en condiciones de discapacidad, abandono, falta de atención y presenta enfermedades asociadas con su estado nutricional, esto hace necesario determinarlo de forma adecuada. Objetivo: Analizar la concordancia entre diferentes criterios de clasificación nutricional según el Índice de Masa Corporal, a partir de una encuesta poblacional de envejecimiento, Colombia 2015. Material y métodos: Se utilizaron cuatro criterios y la concordancia entre las categorías del estado nutricional. Se calculó con los índices de Kappa directo y ponderado. Resultados: Las concordancias fueron moderadas y buenas, la menor proporción de bajo peso (3,4%) se obtuvo utilizando el criterio Organización Mundial de la Salud y la más alta (22,6%) con Organización Panamericana de Salud (p<0,05). El bajo peso se incrementa a medida que aumenta la edad, mientras el exceso de peso disminuye. Conclusiones: La clasificación nutricional cambia según el criterio y puntos de corte, el de la Sociedad Española de Nutrición Parenteral y Enteral, tuvo la mayor concordancia comparado con el de la Organización Mundial de la Salud y mejor capacidad para detectar deficiencia nutricional en la población adulta mayor.

Introduction: Aging is an irreversible process that generates a permanent increase in the 60 and older population. This vulnerable population lives in conditions of disability, neglect, lack of attention, and they present with illnesses related to their nutritional status, which is why it is necessary to understand it fully. Objective: To analyze the accordance between different criteria of nutritional classification according to the Body Mass Index, using an aging population survey, Colombia 2015. Materials and methods: Four criteria were used as well as accordance between categories of nutritional status. Direct and weighted Kappa indices were calculated. Results: The accordance was moderate and good, the lowest proportion of low weight (3.4%) was obtained using the World Health Organization criteria and the highest (22.6%) with the Pan American Health Organization (p<0.05). Low weight is increased as one ages, while excessive weight decreases. Conclusions: Nutritional classification changes depending on the criteria and cut-off points. The criteria of the Spanish Society of Parenteral and Enteral Nutrition had the highest accordance with the World Health Organization and the best capacity in detecting nutritional deficiency in the older adult population.

[Time trend of undernutrition mortality in Colombia, 2005-2019Tendência temporal da mortalidade por desnutrição na Colômbia, 2005-2019]. / Tendencia temporal de la mortalidad por desnutrición en Colombia, 2005-2019.

Objective: To describe the time trends of mortality attributable to malnutrition in Colombia in the period 2005-2019, overall and disaggregated by age and sex. Methods: Ecological study based on secondary data on mortality due to undernutrition as the underlying cause of death according to vital statistics. Crude, age- and sex-specific, and age-standardized annual mortality rates per 100 000 population were calculated. The direct method was used, and the reference population was that proposed by the World Health Organization for 2000-2025. A segmented linear regression or change-point analysis was performed. Results: A total of 26 200 records of deaths due to undernutrition were analyzed for the study period, which corresponds to 0.84% of the total number of deaths in Colombia. The mortality rate in the 0-to-4-year age group was 9.9 per 100 000 population; in the 85-and-older age group, it reached 137 deaths per 100 000 population. All significant adjustments had a negative impact on the model trend, indicating a reduction in mortality rates. The annual percent change was significant for the period 2007-2017, when the mortality rate decreased 2.8% in men (95% confidence interval [95%CI]: -4.3, -1.3) and 3.2% in women (95%CI: -5.0, -1.4). Conclusions: The overall prevalence of mortality attributable to undernutrition in Colombia is low, increasing at the extremes of age, and has been following a downward trend, especially among younger age groups and women.

Objetivo: Descrever a tendência temporal geral e desagregada por idade e sexo da mortalidade por desnutrição na Colômbia no período entre 2005 e 2019. Método: Estudo ecológico baseado em dados secundários de mortalidade por desnutrição como causa básica de morte, de acordo com estatísticas vitais. Foram calculadas as taxas de mortalidade anuais por 100 mil habitantes brutas, específicas por idade e sexo, e padronizadas por idade. Foi utilizado o método direto e a população de referência considerada foi a proposta pela Organização Mundial da Saúde 2000-2025. Foi realizada regressão linear segmentada ou por pontos de mudança. Resultados: Foi analisado um total de 26 200 registros de morte por desnutrição no período do estudo, que corresponde a 0,84% do total de mortes na Colômbia. A taxa de mortalidade no grupo de 0 a 4 anos foi de 9,9 por 100 mil habitantes, e nos de 85 anos ou mais, foi de 137 mortes por 100 mil habitantes. Todos os ajustes significativos na tendência do modelo foram negativos, o que indica uma redução nas taxas de mortalidade. A porcentagem de mudança anual foi significativa para o período 2007-2017, quando a taxa de mortalidade caiu 2,8% nos homens (intervalo de confiança de 95% [IC95%]: -4,3--1,3) e 3,2% nas mulheres (IC95%: -5,0--1,4). Conclusões: A mortalidade por desnutrição na Colômbia é um evento de baixa prevalência em geral, mais elevada nos extremos do curso de vida e com tendência de queda, principalmente nas faixas etárias mais jovens e nas mulheres.

Tendencia temporal de la mortalidad por desnutrición en Colombia, 2005-2019

[RESUMEN]. Objetivo. Describir la tendencia temporal general y desagregada por edad y sexo de la mortalidad por desnutrición en Colombia en el período 2005-2019. Método. Estudio ecológico a partir de datos secundarios de mortalidad por desnutrición como causa básica de defunción según estadísticas vitales. Se calcularon las tasas de mortalidad anuales por 100 000 habitantes, crudas, específicas por edad y sexo y estandarizadas por edad. Se utilizó el método directo y se tomó como población de referencia la propuesta por la Organización Mundial de la Salud 2000-2025. Se efectuó una regresión lineal segmentada o de puntos de cambio. Resultados. Se analizó un total de 26 200 registros de muerte por desnutrición para el período de estudio, que corresponde a 0,84% del total de defunciones en Colombia. La tasa de mortalidad en el grupo de 0 a 4 años fue de 9,9 por 100 000 habitantes; en los de 85 y más años, fue de 137 muertes por 100 000 habitantes. Todos los ajustes significativos en la tendencia del modelo fueron negativos, lo que indica una reducción en las tasas de mortalidad. El porcentaje de cambio anual fue significativo para el período 2007-2017, cuando la tasa de mortalidad disminuyó 2,8% en los hombres (intervalo de confianza del 95% [IC95%]: −4,3-−1,3) y 3,2% en las mujeres (IC95%: −5,0-−1,4). Conclusiones. La mortalidad por desnutrición en Colombia es un evento de baja prevalencia en general, más elevada en los extremos del curso de vida, con una tendencia al descenso, principalmente en los grupos de edad más jóvenes y en las mujeres.

[ABSTRACT]. Objective. To describe the time trends of mortality attributable to malnutrition in Colombia in the period 2005- 2019, overall and disaggregated by age and sex. Methods. Ecological study based on secondary data on mortality due to undernutrition as the underlying cause of death according to vital statistics. Crude, age- and sex-specific, and age-standardized annual mortality rates per 100 000 population were calculated. The direct method was used, and the reference population was that proposed by the World Health Organization for 2000-2025. A segmented linear regression or changepoint analysis was performed. Results. A total of 26 200 records of deaths due to undernutrition were analyzed for the study period, which corresponds to 0.84% of the total number of deaths in Colombia. The mortality rate in the 0-to-4-year age group was 9.9 per 100 000 population; in the 85-and-older age group, it reached 137 deaths per 100 000 population. All significant adjustments had a negative impact on the model trend, indicating a reduction in mortality rates. The annual percent change was significant for the period 2007-2017, when the mortality rate decreased 2.8% in men (95% confidence interval [95%CI]: -4.3, -1.3) and 3.2% in women (95%CI: -5.0, -1.4). Conclusions. The overall prevalence of mortality attributable to undernutrition in Colombia is low, increasing at the extremes of age, and has been following a downward trend, especially among younger age groups and women.

[RESUMO]. Objetivo. Descrever a tendência temporal geral e desagregada por idade e sexo da mortalidade por desnutrição na Colômbia no período entre 2005 e 2019. Método. Estudo ecológico baseado em dados secundários de mortalidade por desnutrição como causa básica de morte, de acordo com estatísticas vitais. Foram calculadas as taxas de mortalidade anuais por 100 mil habitantes brutas, específicas por idade e sexo, e padronizadas por idade. Foi utilizado o método direto e a população de referência considerada foi a proposta pela Organização Mundial da Saúde 2000- 2025. Foi realizada regressão linear segmentada ou por pontos de mudança. Resultados. Foi analisado um total de 26 200 registros de morte por desnutrição no período do estudo, que corresponde a 0,84% do total de mortes na Colômbia. A taxa de mortalidade no grupo de 0 a 4 anos foi de 9,9 por 100 mil habitantes, e nos de 85 anos ou mais, foi de 137 mortes por 100 mil habitantes. Todos os ajustes significativos na tendência do modelo foram negativos, o que indica uma redução nas taxas de mortalidade. A porcentagem de mudança anual foi significativa para o período 2007-2017, quando a taxa de mortalidade caiu 2,8% nos homens (intervalo de confiança de 95% [IC95%]: -4,3--1,3) e 3,2% nas mulheres (IC95%: -5,0--1,4). Conclusões. A mortalidade por desnutrição na Colômbia é um evento de baixa prevalência em geral, mais elevada nos extremos do curso de vida e com tendência de queda, principalmente nas faixas etárias mais jovens e nas mulheres.

Tendencia temporal de la mortalidad por desnutrición en Colombia, 2005-2019

[RESUMEN]. Objetivo. Describir la tendencia temporal general y desagregada por edad y sexo de la mortalidad por desnutrición en Colombia en el período 2005-2019. Método. Estudio ecológico a partir de datos secundarios de mortalidad por desnutrición como causa básica de defunción según estadísticas vitales. Se calcularon las tasas de mortalidad anuales por 100 000 habitantes, crudas, específicas por edad y sexo y estandarizadas por edad. Se utilizó el método directo y se tomó como población de referencia la propuesta por la Organización Mundial de la Salud 2000-2025. Se efectuó una regresión lineal segmentada o de puntos de cambio. Resultados. Se analizó un total de 26 200 registros de muerte por desnutrición para el período de estudio, que corresponde a 0,84% del total de defunciones en Colombia. La tasa de mortalidad en el grupo de 0 a 4 años fue de 9,9 por 100 000 habitantes; en los de 85 y más años, fue de 137 muertes por 100 000 habitantes. Todos los ajustes significativos en la tendencia del modelo fueron negativos, lo que indica una reducción en las tasas de mortalidad. El porcentaje de cambio anual fue significativo para el período 2007-2017, cuando la tasa de mortalidad disminuyó 2,8% en los hombres (intervalo de confianza del 95% [IC95%]: −4,3-−1,3) y 3,2% en las mujeres (IC95%: −5,0-−1,4). Conclusiones. La mortalidad por desnutrición en Colombia es un evento de baja prevalencia en general, más elevada en los extremos del curso de vida, con una tendencia al descenso, principalmente en los grupos de edad más jóvenes y en las mujeres.

[ABSTRACT]. Objective. To describe the time trends of mortality attributable to malnutrition in Colombia in the period 2005- 2019, overall and disaggregated by age and sex. Methods. Ecological study based on secondary data on mortality due to undernutrition as the underlying cause of death according to vital statistics. Crude, age- and sex-specific, and age-standardized annual mortality rates per 100 000 population were calculated. The direct method was used, and the reference population was that proposed by the World Health Organization for 2000-2025. A segmented linear regression or changepoint analysis was performed. Results. A total of 26 200 records of deaths due to undernutrition were analyzed for the study period, which corresponds to 0.84% of the total number of deaths in Colombia. The mortality rate in the 0-to-4-year age group was 9.9 per 100 000 population; in the 85-and-older age group, it reached 137 deaths per 100 000 population. All significant adjustments had a negative impact on the model trend, indicating a reduction in mortality rates. The annual percent change was significant for the period 2007-2017, when the mortality rate decreased 2.8% in men (95% confidence interval [95%CI]: -4.3, -1.3) and 3.2% in women (95%CI: -5.0, -1.4). Conclusions. The overall prevalence of mortality attributable to undernutrition in Colombia is low, increasing at the extremes of age, and has been following a downward trend, especially among younger age groups and

[RESUMO]. Objetivo. Descrever a tendência temporal geral e desagregada por idade e sexo da mortalidade por desnutrição na Colômbia no período entre 2005 e 2019. Método. Estudo ecológico baseado em dados secundários de mortalidade por desnutrição como causa básica de morte, de acordo com estatísticas vitais. Foram calculadas as taxas de mortalidade anuais por 100 mil habitantes brutas, específicas por idade e sexo, e padronizadas por idade. Foi utilizado o método direto e a população de referência considerada foi a proposta pela Organização Mundial da Saúde 2000- 2025. Foi realizada regressão linear segmentada ou por pontos de mudança. Resultados. Foi analisado um total de 26 200 registros de morte por desnutrição no período do estudo, que corresponde a 0,84% do total de mortes na Colômbia. A taxa de mortalidade no grupo de 0 a 4 anos foi de 9,9 por 100 mil habitantes, e nos de 85 anos ou mais, foi de 137 mortes por 100 mil habitantes. Todos os ajustes significativos na tendência do modelo foram negativos, o que indica uma redução nas taxas de mortalidade. A porcentagem de mudança anual foi significativa para o período 2007-2017, quando a taxa de mortalidade caiu 2,8% nos homens (intervalo de confiança de 95% [IC95%]: -4,3--1,3) e 3,2% nas mulheres (IC95%: -5,0--1,4). Conclusões. A mortalidade por desnutrição na Colômbia é um evento de baixa prevalência em geral, mais elevada nos extremos do curso de vida e com tendência de queda, principalmente nas faixas etárias mais jovens e nas mulheres.

The innervation of the biceps brachii and brachialis muscles in specimens with a high incidence of an accessory biceps head.

We describe the patterns of motor branches to the elbow flexors in 106 fresh-frozen cadaveric upper extremities from 53 donors of the Latin American mestizo race. We identified a 20% incidence of an accessory biceps head. The innervation patterns to this accessory head were specifically described and added to the Yang classification as Type IV for the biceps and Type III for the brachialis. The patterns arising from the musculocutaneous nerve to the biceps brachii were of Type I in 69%, Type II in 9%, Type III in 7% and Type IV in 11%, and to the brachialis of Type I in 77%, Type II in 11% and Type III in 9%. In 4%, the branches did not originate from the musculocutaneous nerve. We hypothesize that the branch to the accessory biceps head might be considered as a donor for nerve transfer in selected brachial plexus injuries.

Tendencia temporal de la mortalidad por desnutrición en Colombia, 2005-2019 / Time trend of undernutrition mortality in Colombia, 2005-2019 / Tendência temporal da mortalidade por desnutrição na Colômbia, 2005-2019

RESUMEN Objetivo. Describir la tendencia temporal general y desagregada por edad y sexo de la mortalidad por desnutrición en Colombia en el período 2005-2019. Método. Estudio ecológico a partir de datos secundarios de mortalidad por desnutrición como causa básica de defunción según estadísticas vitales. Se calcularon las tasas de mortalidad anuales por 100 000 habitantes, crudas, específicas por edad y sexo y estandarizadas por edad. Se utilizó el método directo y se tomó como población de referencia la propuesta por la Organización Mundial de la Salud 2000-2025. Se efectuó una regresión lineal segmentada o de puntos de cambio. Resultados. Se analizó un total de 26 200 registros de muerte por desnutrición para el período de estudio, que corresponde a 0,84% del total de defunciones en Colombia. La tasa de mortalidad en el grupo de 0 a 4 años fue de 9,9 por 100 000 habitantes; en los de 85 y más años, fue de 137 muertes por 100 000 habitantes. Todos los ajustes significativos en la tendencia del modelo fueron negativos, lo que indica una reducción en las tasas de mortalidad. El porcentaje de cambio anual fue significativo para el período 2007-2017, cuando la tasa de mortalidad disminuyó 2,8% en los hombres (intervalo de confianza del 95% [IC95%]: −4,3-−1,3) y 3,2% en las mujeres (IC95%: −5,0-−1,4). Conclusiones. La mortalidad por desnutrición en Colombia es un evento de baja prevalencia en general, más elevada en los extremos del curso de vida, con una tendencia al descenso, principalmente en los grupos de edad más jóvenes y en las mujeres.

ABSTRACT Objective. To describe the time trends of mortality attributable to malnutrition in Colombia in the period 2005-2019, overall and disaggregated by age and sex. Methods. Ecological study based on secondary data on mortality due to undernutrition as the underlying cause of death according to vital statistics. Crude, age- and sex-specific, and age-standardized annual mortality rates per 100 000 population were calculated. The direct method was used, and the reference population was that proposed by the World Health Organization for 2000-2025. A segmented linear regression or change-point analysis was performed. Results. A total of 26 200 records of deaths due to undernutrition were analyzed for the study period, which corresponds to 0.84% of the total number of deaths in Colombia. The mortality rate in the 0-to-4-year age group was 9.9 per 100 000 population; in the 85-and-older age group, it reached 137 deaths per 100 000 population. All significant adjustments had a negative impact on the model trend, indicating a reduction in mortality rates. The annual percent change was significant for the period 2007-2017, when the mortality rate decreased 2.8% in men (95% confidence interval [95%CI]: -4.3, -1.3) and 3.2% in women (95%CI: -5.0, -1.4). Conclusions. The overall prevalence of mortality attributable to undernutrition in Colombia is low, increasing at the extremes of age, and has been following a downward trend, especially among younger age groups and women.

RESUMO Objetivo. Descrever a tendência temporal geral e desagregada por idade e sexo da mortalidade por desnutrição na Colômbia no período entre 2005 e 2019. Método. Estudo ecológico baseado em dados secundários de mortalidade por desnutrição como causa básica de morte, de acordo com estatísticas vitais. Foram calculadas as taxas de mortalidade anuais por 100 mil habitantes brutas, específicas por idade e sexo, e padronizadas por idade. Foi utilizado o método direto e a população de referência considerada foi a proposta pela Organização Mundial da Saúde 2000-2025. Foi realizada regressão linear segmentada ou por pontos de mudança. Resultados. Foi analisado um total de 26 200 registros de morte por desnutrição no período do estudo, que corresponde a 0,84% do total de mortes na Colômbia. A taxa de mortalidade no grupo de 0 a 4 anos foi de 9,9 por 100 mil habitantes, e nos de 85 anos ou mais, foi de 137 mortes por 100 mil habitantes. Todos os ajustes significativos na tendência do modelo foram negativos, o que indica uma redução nas taxas de mortalidade. A porcentagem de mudança anual foi significativa para o período 2007-2017, quando a taxa de mortalidade caiu 2,8% nos homens (intervalo de confiança de 95% [IC95%]: -4,3--1,3) e 3,2% nas mulheres (IC95%: -5,0--1,4). Conclusões. A mortalidade por desnutrição na Colômbia é um evento de baixa prevalência em geral, mais elevada nos extremos do curso de vida e com tendência de queda, principalmente nas faixas etárias mais jovens e nas mulheres.

Superficial communication between ulnar and media nerves in the hand: an anatomical study / Comunicación superficial entre los nervios ulnar y mediano de la mano: un estudio anatómico

SUMMARY: The objective of this study was to characterize the communication between ulnar and the median nerve in the superficial palmar region from a sample of mestizo-raced population predominant in Latin America. The superficial palmar regions of 53 fresh cadaveric specimens were evaluated, whom of which underwent necropsy procedure at the Institute of Legal Medicine. Dissection was performed by planes until visualizing the presence of the Communicating Branch (CB) between the digital branches of the ulnar nerve (UN) and the median nerve (MN). Qualitative and morphometric evaluation of the CB was carried out. A CB were observed in 82/ 106 (77.4 %) of the cadaveric specimens studied, of which, 38/53 (71.7 %) were bilateral, 15/53 (28.3 %) unilateral; this being a statistically significant difference (p <0.002). Oblique trajectory of the CB between the fourth and third common digital nerve was observed in 70 (85.4 %) specimens, while the CB with transverse trajectory was found in 7 (8.5 %) regions and in a plexiform form in 5 (6.1 %) cases. The length of the CB was 20.2 ± 5.1 mm and the distances from the upper edge of the flexor retinaculum to the proximal and distal points of the CB were 25 ± 6 mm and 37.4 ± 8.3 mm respectively. The anatomical characteristics of the CB patterns, as well as the morphometric CB findings and their points of reference from the carpal flexor retinaculum, make it possible to delimit a safe area of surgical access in the first-fifth proximal of the palmar region, during the surgical approach of carpal tunnel syndrome.

RESUMEN: El objetivo de este estudio fue caracterizar la comunicación entre los nervios ulnar y mediano en la región palmar superficial a partir de una muestra de población de raza mestiza predominante en América Latina. Se evaluaron las regiones palmares superficiales de 53 especímenes cadavéricos frescos, los cuales fueron sometidos procedimiento de necropsia en el Instituto de Medicina Legal. La disección se realizó por planos hasta visualizar la presencia del ramo comunicante (RC) entre los ramos digitales palmares del nervio ulnar (NU) y del nervio mediano (NM). Se realizó evaluación cualitativa y morfométrica del RC, observándose RC en 82/106 (77,4 %) de los especímenes cadavéricos estudiados, de los cuales 38/53 (71,7 %) eran bilaterales, 15/53 (28,3 %) unilaterales; siendo esta una diferencia estadísticamente significativa (p <0,002). Se observó trayectoria oblicua del RC entre el cuarto y tercer nervio digital palmar común en 70 muestras (85,4 %), mientras que el RC con trayectoria transversal se encontró en 7 casos (8,5 %) y en forma plexiforme en 5 casos (6,1 %). La longitud del RC fue de 20,2 ± 5,1 mm y las distancias desde el margen superior del retináculo flexor hasta los puntos proximal y distal del RC fueron de 25 ± 6 mm y 37,4 ± 8,3 mm, respectivamente. Así, los hallazgos morfométricos del RC y sus puntos de referencia, desde el retináculo flexor, permiten delimitar una zona segura de acceso quirúrgico en el primer-quinto proximal de la región palmar, durante el abordaje quirúrgico del síndrome del túnel carpiano.

Microscopic analysis of the myocardial bridges and their relationship with atheromatous plaque / Análisis microscópico de los puentes miocárdicos y su relación con la placa ateromatosa

SUMMARY: Most histopathological studies have reported that the segment of the coronary artery below the myocardial bridge does not present atheromatous plaque, while the segment proximal to the myocardial bridge may have it. The aim of this study was to evaluate the microscopic environment of myocardial bridges. This descriptive study was carried out with 60 hearts of individuals who underwent autopsy at the National Institute of Legal Medicine and Forensic Sciences in Bucaramanga-Colombia. For each specimen, the coronary arteries and their branches were dissected, removing the subepicardial adipose tissue to identify the myocardial bridges and obtain histological sections of the compromised arterial branches. The presence of myocardial bridges was observed in 22 hearts (36.7%) with a length of 17.31 + 4.41 mm and a thickness of 904.57 + 312.27 mm. The coronary vessel caliber at the prepontine level was 246.57 + 49.33 mm and was significantly higher than in the pontine (188.92 + 60.55 mm) and postpontin (190.40 + 47 mm) segments (p=0.001 for both values). Atheromatous plaque was observed in the prepontine segment in 12 cases (46.15 %) and in 8 samples (30.76%) at the pontine level, but in this segment, there was slight damage to the vascular endothelium, or phase I level. The thickness of the tunica intima in the cases with atheromatous plaque was 15.68 + 13.39 mm and that of the plaque-free segments was 5.10 + 4.40 mm (p=0.005), and in the pontine segment the overlying periarterial adipose tissue had a thickness of 72.01 + 69.44 mm, which was higher than the other three locations (p=0.005). The morphometry of the perivascular fat pad and the presence of phase I atheromatous plaque are the main contributions of this study to the histology of myocardial bridges.

RESUMEN: La mayoría de los estudios histopatológicos han reportado que el segmento de la arteria coronaria debajo del puente miocárdico no presenta placa ateromatosa, mientras que el segmento proximal al puente miocárdico puede tenerla. El objetivo de este estudio fue evaluar el entorno microscópico de los puentes miocárdico. Este estudio descriptivo se realizó con 60 corazones de individuos a quienes se les práctico autopsia en el Instituto Nacional de Medicina Legal y Ciencias Forenses de Bucaramanga-Colombia. Para cada espécimen se realizó disección de las arterias coronarias y sus ramas, eliminando el tejido adiposo subepicárdico para identificar los puentes miocárdicos y obtener secciones histológicas de las ramas arteriales comprometidas. Se observó presencia de puentes miocárdicos en 22 corazones (36,7 %) con una longitud de 17.31 + 4.41 mm y un espesor de 904.57 + 312.27 mm. El calibre del vaso coronario a nivel prepontino fue 246.57 + 49.33 mm y fue significativamente mayor que en el segmento pontino (188.92 + 60.55 mm) y pospontino (190.40 + 47 mm) (p=0.001 para ambos valores). Se observó placa ateromatosa en el segmento prepontino en 12 casos (46.15 %) y en 8 muestras (30.76%) al nivel pontino, pero en este segmento, correspondieron a fase I, con ligero daño en el endotelio vascular. El espesor de la túnica íntima en los casos con placa ateromatosa fue de 15.68 + 13.39 mm y de los segmentos libres de placa fue 5.10 + 4.40 mm (p=0.005) y en el segmento pontino el tejido adiposo periarterial suprayacente presento un espesor de 72.01 + 69.44 mm, el cual fue mayor a las otras tres ubicaciones (p=0.005). La morfometría de la almohadilla adiposa perivascular y la presencia de placa ateromatosa en fase I son los principales aportes de este estudio a la histología de los puentes miocárdicos.

Electrochemical Hydrogen Evolution over Hydrothermally Synthesized Re-Doped MoS2 Flower-Like Microspheres.

In this research, we report a simple hydrothermal synthesis to prepare rhenium (Re)- doped MoS2 flower-like microspheres and the tuning of their structural, electronic, and electrocatalytic properties by modulating the insertion of Re. The obtained compounds were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Structural, morphological, and chemical analyses confirmed the synthesis of poorly crystalline Re-doped MoS2 flower-like microspheres composed of few stacked layers. They exhibit enhanced hydrogen evolution reaction (HER) performance with low overpotential of 210 mV at current density of 10 mA/cm2, with a small Tafel slope of 78 mV/dec. The enhanced catalytic HER performance can be ascribed to activation of MoS2 basal planes and by reduction in charge transfer resistance during HER upon doping.

Biometría del musculo tríceps braquial y de sus puntos motores: un estudio anatómico directo en una muestra de población colombiana / Biometry of the brachial triceps muscle and its motor points: a direct anatomical study in a sample of colombian population

Las características anatómicas del músculo tríceps braquial (MTB) determinan la velocidad de reparación y capacidad de generación de torque. El MTB es inervado típicamente por el nervio radial (NR), pero existen reportes de inervación por parte del nervio axilar. El propósito de este estudio fue evaluar los componentes musculotendinosos y nerviosos del MTB. Mediante disección directa en una muestra de 48 brazos de población mestiza colombiana, se evaluó morfometría musculotendinosa, ramos nerviosos, puntos motores (PM) y origen de la inervación del MTB. Las longitudes de las cabezas medial, lateral y larga del MTB correspondieron al 77,3 %, 86 % y 97 % respectivamente de la longitud del brazo. El MTB fue inervado en la totalidad de la muestra por el NR quien emitió entre dos y cinco ramos motores. El primer ramo inervó la cabeza larga en el 100 % de los casos y emergió lateral a la banda tendinosa de inserción del músculo latísimo del dorso. La cabeza larga recibió con mayor frecuencia tres PM (26,6 %), ubicados en el 85 % de los especímenes a 4-10 cm del origen muscular; mientras que la cabeza lateral recibió tres PM en el 44,4 % de la muestra. No hubo diferencias estadísticamente significativas entre el número de PM del MTB izquierdo con relación al derecho (p=0,578). El área de dispersión de PM, así como la morfometría del MTB, son de relevancia clínica, debido a su uso en la estimulación eléctrica neuromuscular y transferencias nerviosas. Los resultados presentados en el presente estudio se constituyen en guía que facilita realizar estas acciones terapéuticas.

The anatomical characteristics of the triceps brachii (TBM) muscle determine the repair speed and torque generation capacity. The TBM is typically innervated by the radial nerve (RN), but there are reports of innervation by the axillary nerve. The aim of this study was to evaluate musculotendinous and nervous components of TBM. Through direct dissection in a sample of 48 arms of the Colombian mestizo population, we evaluated musculotendinous morphometry, nerve branches, motor points (MP) and origin of TBM innervation. The lengths of the medial, lateral and long heads of the TBM corresponded to 77.3 %, 86 % and 97 % of the arm length respectively. The TBM was innervated in the whole sample by the NR who issued between two and five motor branches. The first branch innervated the long head in 100 % of cases and emerged laterally to the tendinous band insertion of the latissimus dorsi muscle. The long head received three MP (26.6 %), located in 85 % of the specimens at 4 - 10 cm of muscular origin; while the lateral head received three MP in 44.4 % of the sample. There were no statistically significant differences between the number of MP of the left TBM in relation to the right (p = 0.578). The dispersion area of MP, as well as TBM morphometry are clinically relevant due to their use in neuromuscular electrical stimulation and nerve transfers. The findings presented in this study are a guide to facilitate results in this type of therapeutic action.

Histiocitosis de las células de Langerhans: Presentación de caso y revisión de la literatura / Langerhans Cell Histocytosis: Case Report and Literature Review

La histiocitosis de células de Langerhans (HCL) es una entidad rara que compromete estructuras óseas, tejidos blandos e incluso lesiones específicas de órganos como el pulmón. Se presenta la revisión de la literatura de la histiocitosis de las células de Langerhans y el caso de una paciente de 7 años de edad, sin antecedentes pre, peri o posnatales, previamente sana; quien, posterior a caída desde su propia altura, manifiesta alteraciones neurológicas de sus miembros inferiores que afectan su fuerza y la respuesta a los reflejos osteotendinosos. Se practicaron estudios imagenológicos que mostraron lesiones típicas óseas de la histiocitosis.

Langerhans cell histiocytosis is a rare disease that involves bone structure, soft tissues and even specific injuries to organs such as lung. This paper presents a literature review of Langerhans cell histiocytosis and it reports the case of a previously healthy 7-year-old female patient, without pre-, peri-, and postnatal history, who after an own height fall presents neurological alterations in her lower limbs affecting her muscle strength and the response to the osteotendinous reflexes. Imaging studies showing typical bone lesions of histiocytosis were performed.

Biometría de dientes anteriores en mestizos: proporción largo/ancho intradental / Biometry of anterior teeth in mestizos: intradental long / wide ratio

Las proporciones largo/ancho intradental han sido propuestas en más de once diferentes modelos a la fecha pero no se han estudiando en población mestiza Colombiana. Se utilizaron modelos de agrupamiento jerárquico (K-Means) para entender cual explica mejor la distribución de los datos. También se analizaron co-variables de sexo, edad y atrición leve para evaluar su influencia sobre la distribución general. Fueron utilizadas fotografías estandarizadas de dientes anteriores de 274 individuos de ambos sexos con dientes completamente erupcionados y sanos. Las mediciones fueron realizadas con programas informáticos calibrados (error de 0,05 mm). Se utilizó la prueba Chi Cuadrado para demostrar que las co-variables el sexo (valor de p= 0,09), edad (valor de p= 0,54) y atrición leve (valor de p= 0,32) no tuvieron impacto en la distribución de las proporciones dentales. Con respecto al análisis de conglomerados a través de las K-Means, se identificaron dos grupos diferenciados en toda la muestra: proporciones verticales (dientes mas largos) y proporciones horizontales (dientes mas anchos). Un tercer grupo solapado entre las dos tendencias lo denominamos de proporciones balanceadas. No hay un modelo de proporción intradental universal que pueda describir toda la población, pero fue posible encontrar un conjunto de modelos para los diferentes subgrupos de población. Los ideales estéticos se encuentran en abierta interpretación. Los patrones absolutos son imprácticos en biología ya que no predicen la complejidad de esta.

The intradental length / width ratios have been proposed in more than eleven different models to date. However they have not been studied in the Colombian Mestizo population. Hierarchical clustering models (K-Means) were used to understand which best explains the distribution of the data. Co-variables of sex, age, and mild attrition were also analyzed to assess their influence on overall distribution. Standardized photographs of anterior teeth of 274 individuals of both sexes with fully erupted and healthy teeth were used. Measurements were taken with calibrated software (error of 0.05 mm). Chi square test was used to show that the co-variables sex (p value = 0.09), age (p value = 0.54) and mild attrition (p value = 0.32) had no impact In the distribution of dental proportions. With respect to the analysis of conglomerates through the K-Means, two distinct groups were identified throughout the sample: Vertical proportions (longer teeth) and horizontal proportions (wider teeth). A third group overlapping the two trends we called balanced proportions. There is no universal intraday proportion model that can describe the entire population, but it was possible to find a set of models for different population subgroups. Aesthetic ideals are in open interpretation. Absolute patterns are impractical in biology because they do not predict the complexity of biology.

Morphological characterization of the renal vein in pigs (Sus domesticus). Differential analysis with the human renal veins

Despite its importance as an experimental model, information about the morphology of the renal vein (RV) is scarce and limited to qualitative descriptions. The objective of this investigation was to determine the morphological characteristics of the RV and its tributaries in pigs (Sus domesticus). We studied 93 pairs of kidneys of pigs destined to slaughter. This descriptive study evaluated the RV and its tributaries, which were perfused with polyester resin (85% Palatal and 15% styrene). Subsequently for full corrosion pieces were subjected to infusion of KOH (potassium hydroxide) for 10 days. The RV and their tributaries were assessed for shape, trajectory and morphometry. The level of significance was set at p< 0.05. A single RV was found in 93% of the specimens. The caliber of the RV was 12.8±3.05 mm. It was significantly higher on the left side (p=0.043). Length was 26.54±12.81 mm for the right RV and 37.64±13.62 mm for the left RV. The position of the RV in relation with the renal artery was cranial-ventral in 46.2% of the specimens, whereas its origin was hilar in 61.9% of the cases. The emergence of the RV from two tributary veins (pattern Ia) was the most common (76.9%). The morphological characteristics of the VR observed in this study are similar to those reported in humans, so the usefulness of this animal model in procedural applications and hemodynamics is evident

No disponible

Agenesis of the medial gastrocnemius and plantar muscle: case presentation / Agenesia del gastrocnemio medial y del músculo plantar: presentación de caso

We present the case of a left medial gastrocnemius and plantar muscle agenesis in a 58-years old male cadaveric specimen from the Anatomy Laboratory at the Universidad Industrial de Santander (Bucaramanga-Colombia). These unusual muscle absences and associated functional alterations, enrich anatomical knowledge and become important by the time the affected individual may need a reconstructive procedure.

Se presenta un caso de agenesia de los músculos gastrocnemio medial y plantar izquierdos en un espécimen cadavérico masculino de 58 años, del laboratorio de anatomía de la Universidad Industrial de Santander (Bucaramanga- Colombia). Estas raras ausencias musculares enriquecen el conocimiento anatómico con sus alteraciones funcionales concomitantes y permiten postular los posibles procedimientos reconstructivos requeridos en los individuos que las presentan.

Morphological characterization of the renal arteries in the pig: comparative analysis with the human / Caracterización morfológica de las arterias renales en el cerdo: análisis comparativo con el humano

In spite of its importance as an experimental model, information on therenal artery inpigs is scarce.The objective of this work was to determine the morphological characteristics of the renal artery (RA) and its branches in pigs. One hundred and twenty one (121) pairs of kidneys of pigs destined to slaughter by stunning were studied. The RA and its branches were perfused with polyester resin (Palatal 85 % t Styrene 15 %)and subjected to KOH infusion (potassium hydroxide) for total corrosion. Calibers were measured, and trajectories and relations with adjacent arterial structures were evaluated.Continuous variables were assessed with Student's t test,and discrete variables with Pearson's chi square test. The significance level used was p<0.05. The origin of the RA was symmetric in 57 specimens (50.4 %), with the right renal arterybeing more cranial in 55 % of the cases. Single renal arteries were seen in 98.4 %, without significant side differences (p=0.31).The caliber and length of the RA were 5.11mm (SD1.35) and 30.1mm (SD8.63), respectively. A pattern of RA expression that causes one cranial and one caudal polar branch (Type I) was observed in 97.1 % of the cases. The distribution of the RA in cranial and caudal polar branches was found to be higher than what is described in the literature, since these morphometric features have not been reported in prior studies.These findings contribute to a better knowledge in the field of the compared anatomy of the kidney, and allow for applying the pig model in procedural and hemodynamic applications.

A pesar de su importancia como un modelo experimental, la información sobre la arteria renal en los porcinos es escasa. El objetivo de este trabajo fue determinar las características morfológicas de la arteria renal (AR) y sus ramas en cerdos. Fueron estudiados 121 pares de riñones de cerdos destinados al sacrificio con método de aturdimiento. Las AR y sus ramas fueron perfundidas con resina poliéster (Palatal 85 % t Estireno 15 %) y sometidas a infusión de KOH (hidróxido de potasio) para corrosión total. Se midieron calibres, evaluaron trayectorias y relaciones con estructuras arteriales adyacentes. Se evaluó las variables continuas con el test de t student y las variables discretas con el test de chi cuadrado de Pearson. El nivel de significancia usado fue de p<0,05. El origen de la AR fue simétrico en 57 muestras (50,4 %), siendo la arteria renal derecha la más craneal en el 55 % de los casos. Se observó arterias renales únicas en el 98,4 %, sin diferencias significativas de lado (p=0,31). El calibre y la longitud de la AR fue 5,11 mm (SD 1,35) y 30,1 mm (SD 8,63) respectivamente. En el 97,1 % se observó un patrón de expresión de la AR que origina una rama polar craneal y una caudal (Tipo I). La distribución en ramas polares craneal y caudal de la AR es superior a lo descrito en la literatura, en tanto que las características morfométricas no han sido reportadas en estudios previos. Estos hallazgos contribuyen al mejor conocimiento en el campo de la anatomía comparada del riñón y permiten postular al modelo porcino en aplicaciones procedimentales y hemodinámicas.

Conductas de higiene en el uso de estetoscopios de estudiantes de un programa de medicina de la ciudad de Tunja, Colombia / Hygiene behaviors in the use of stethoscopes of students of a medicine program of the city of Tunja, Colombia

Introducción: múltiples investigaciones han demostrado que los estetoscopios se encuentran colonizados por bacterias causantes de infecciones humanas. A pesar de ello, no se han definido las causas por las que estos instrumentos se contaminan. Objetivo: determinar las conductas de higiene que tienen los estudiantes de un programa de medicina de la ciudad de Tunja, Colombia, en el uso de los estetoscopios. Materiales y métodos: se seleccionaron 50 estudiantes de medicina quienes diligenciaron un cuestionario con preguntas cerradas, construido con base en grupos focales que permitieron caracterizar las conductas de uso intra y extrahospitalarias del estetoscopio. Además, a cada estudiante participante se le solicitó su estetoscopio para tomar muestras de cuatro partes del mismo, que posteriormente fueron cultivadas en agar nutritivo y caracterizadas macroscópica y microscópicamente por medio de la coloración de Gram. Resultados: de los 50 estudiantes que diligenciaron el cuestionario se evidenció que el 48% nunca había limpiado el estetoscopio, el 24% lo limpiaba con alcohol antiséptico y el 2% realizaba limpieza antes de la valoración del paciente. En el 100% de los estetoscopios se aislaron colonias bacterianas, principalmente cocos Gram positivos, siendo el diafragma la parte más contaminada de este instrumento. Conclusiones: se determinaron conductas inadecuadas en el uso del estetoscopio a nivel intra y extrahospitalario, así como la falta de información para su adecuada desinfección. (AU)

Introduction: multiple investigations have shown that bacteria causing human infections colonize stethoscopes. However, the reasons why these instruments are contaminated have not been defined. Objective: To determine the hygiene behaviors that medicine students have in the use of stethoscopes. Materials and methods: 50 medicine students were selected to complete a questionnaire with closed questions, based on focus groups that allowed characterizing the intra and extrahospital behavior of the stethoscope use. In addition, each participant student was asked for his stethoscope in order to take samples of four parts of it, which were later culture on nutritive agar and characterized macroscopically and microscopically by Gram staining. Results: Of the 50 students, who completed the questionnaire, 48% have never cleaned the stethoscope, 24% cleaned it with antiseptic alcohol, and 2% cleaned before the patient's evaluation. In 100% of the stethoscopes bacterial colonies were isolated, mainly Gram-positive cocci, been diaphragm the most contaminated part of this instrument. Conclusions: inadequate behaviors were determined in the intra- and extra-hospital stethoscope use, as well as lack of information for it adequate disinfection. (AU)