Exploring the Link between Interoceptive Body Awareness and Suicidal Orientation in University Students: A Cross-Sectional Study.

INTRODUCTION: The transition to college life can impact the mental health of students. There are mental health care strategies that promote connection with the body's internal signals, which can help to improve mental well-being, manage emotions, and reduce the risk of suicide in university students. AIM: This study aimed to examine the association between interoceptive body awareness variables and suicidal orientation in a sample of 169 undergraduate students in Colombia. METHODS: An observational, cross-sectional study was conducted in 2023 with Colombian students as the participants. RESULTS: The findings revealed a significant and moderately negative correlation between the Multidimensional Assessment of Interoceptive Awareness (MAIA) total score and the Inventory of Suicide Orientation (ISO-30) total score (r = -0.54, p < 0.001). Confidence and self-regulation were identified as the most influential factors in the relationship between MAIA and ISO-30. Significant correlations were observed (p < 0.001), indicating moderate correlation values ranging from -0.43 to -0.57. DISCUSSION: Our findings support the existence of a negative correlation between interoceptive body awareness and suicidal orientation. Further research is needed to better understand this relationship and to develop specific interventions based on body awareness to prevent suicide orientation. CONCLUSION: There are practical implications associated with recognizing the importance of body awareness in relation to decreasing suicidal orientation, and multidisciplinary teams addressing mental health can incorporate this knowledge.

Psychometric Properties of the Multidimensional Assessment of Interoceptive Awareness (MAIA) Questionnaire in Colombian University Students.

INTRODUCTION: The university student population is influenced by multiple factors that affect body awareness. Identifying the body awareness status of students is crucial in creating self-care and emotion management programs to prevent diseases and promote health. The Multidimensional Assessment of Interoceptive Awareness (MAIA) questionnaire evaluates interoceptive body awareness in eight dimensions through 32 questions. It is one of the few tools that enable a comprehensive assessment of interoceptive body awareness by involving eight dimensions of analysis. METHOD: The objective of this study is to present the psychometric properties of the Multidimensional Assessment of Interoceptive Awareness (MAIA) to observe to what extent the hypothesized model fits the population of university students in Colombia. A descriptive cross-sectional study was conducted with 202 students who met the inclusion criterion of being undergraduate university students. Data were collected in May 2022. RESULTS: A descriptive analysis of the sociodemographic variables of age, gender, city, marital status, discipline, and history of chronic diseases was performed. JASP 0.16.4.0 statistical software was used to conduct confirmatory factor analysis. A confirmatory factor analysis was performed based on the proposed eight-factor model of the original MAIA, giving a significant p-value and 95% confidence interval. However, when performing loading factor analysis, a low p-value was found for item 6 of the Not Distracting factor, and for the entire Not Worrying factor. DISCUSSION: A seven-factor model with modifications is proposed. CONCLUSIONS: The results of this study confirmed the validity and reliability of the MAIA in the Colombian university student population.

Chagas disease in the context of the 2030 agenda: global warming and vectors.

The 2030 Agenda for Sustainable Development is a plan of action for people, planet and prosperity. Thousands of years and centuries of colonisation have passed the precarious housing conditions, food insecurity, lack of sanitation, the limitation of surveillance, health care programs and climate change. Chagas disease continues to be a public health problem. The control programs have been successful in many countries in reducing transmission by T. cruzi; but the results have been variable. WHO makes recommendations for prevention and control with the aim of eliminating Chagas disease as a public health problem. Climate change, deforestation, migration, urbanisation, sylvatic vectors and oral transmission require integrating the economic, social, and environmental dimensions of sustainable development, as well as the links within and between objectives and sectors. While the environment scenarios change around the world, native vector species pose a significant public health threat. The man-made atmosphere change is related to the increase of triatomines' dispersal range, or an increase of the mobility of the vectors from their sylvatic environment to man-made constructions, or humans getting into sylvatic scenarios, leading to an increase of Chagas disease infection. Innovations with the communities and collaborations among municipalities, International cooperation agencies, local governmental agencies, academic partners, developmental agencies, or environmental institutions may present promising solutions, but sustained partnerships, long-term commitment, and strong regional leadership are required. A new world has just opened up for the renewal of surveillance practices, but the lessons learned in the past should be the basis for solutions in the future.

Chagas disease in the context of the 2030 agenda: global warming and vectors

The 2030 Agenda for Sustainable Development is a plan of action for people, planet and prosperity. Thousands of years and centuries of colonisation have passed the precarious housing conditions, food insecurity, lack of sanitation, the limitation of surveillance, health care programs and climate change. Chagas disease continues to be a public health problem. The control programs have been successful in many countries in reducing transmission by T. cruzi; but the results have been variable. WHO makes recommendations for prevention and control with the aim of eliminating Chagas disease as a public health problem. Climate change, deforestation, migration, urbanisation, sylvatic vectors and oral transmission require integrating the economic, social, and environmental dimensions of sustainable development, as well as the links within and between objectives and sectors. While the environment scenarios change around the world, native vector species pose a significant public health threat. The man-made atmosphere change is related to the increase of triatomines' dispersal range, or an increase of the mobility of the vectors from their sylvatic environment to man-made constructions, or humans getting into sylvatic scenarios, leading to an increase of Chagas disease infection. Innovations with the communities and collaborations among municipalities, International cooperation agencies, local governmental agencies, academic partners, developmental agencies, or environmental institutions may present promising solutions, but sustained partnerships, long-term commitment, and strong regional leadership are required. A new world has just opened up for the renewal of surveillance practices, but the lessons learned in the past should be the basis for solutions in the future.

Manejo endovascular de desconexión tras reparación endovascular de aorta fenestrada / Endovascular management of a disconnected bridging stent during fenestrated endovascular aortic repair

Descripción de una complicación en una reparación de AAA con dispositivo anaconda fenestrada (Vascutek, Teru­mo(R)) por desconexión de stent renal en la que se plantearon estrategias de manejo para su corrección con un adecuado desenlace angiográfico y clínico

Description of complication in repair of AAA with fenestrated anaconda device (Vascutek Ltd./Terumo(R)), due to disconnection of renal stent where management strategies were proposed for its correction with an adequate angiographic and clinical outcome

Enfermedad cardiaca inducida por radioterapia / Radiation induced heart disease

Resumen La enfermedad cardiaca inducida por los tratamientos para el cáncer, como la quimioterapia y radioterapia, se considera cada vez más una enfermedad prevalente, que por tanto amerita conocimiento para el seguimiento adecuado, la prevención y el tratamiento de la misma. Anteriormente, este grupo de investigación publicó el artículo ``Cardiotoxicidad inducida por la quimioterapia: desde las bases moleculares hasta la perspectiva clínica'', en la que se hace una revisión acerca de los diferentes aspectos, incluyendo diagnóstico, fisiopatología, tratamiento y pronóstico de la enfermedad cardiaca inducida por radioterapia.

Abstract The heart disease induced by cancer treatments, such as chemotherapy and radiotherapy, is increasingly being seen as a prevalent disease, and as such it needs to be taken into account for its appropriate follow-up, prevention and treatment. Previously, this research group published the review, ``Chemotherapy-induced cardiotoxicity from the molecular basis to the clinical perspective'', which included a review of the different aspects, including the pathophysiology, treatment, and prognosis of heart disease induced by radiotherapy.

Triatoma dimidiata en Colombia; distribución, ecología e importancia epidemiológica / Triatoma dimidiata in Colombia: Distribution, ecology and epidemiological importance

RESUMEN Triatoma dimidiata es un importante vector de la enfermedad de Chagas en Centroamérica y en los países del norte de Suramérica. En Colombia, tiene una amplia distribución y su presencia se ha reportado en 14 departamentos de las regiones Andina, Caribe, de los Llanos Orientales y del Alto Magdalena, en las cuales ocupa diferentes ecótopos naturales y artificiales. La especie está clasificada como secundaria para la transmisión de Trypanosoma cruzi; sin embargo, su presencia en el ambiente silvestre, peridoméstico y doméstico en la región Andina, y su capacidad de movilizarse entre ellos, le han permitido escapar al control basado en la aspersión con piretroides y ello resalta su importancia en el mantenimiento de la transmisión del parásito debido a la potencial reinfestación de las viviendas. La comprensión de las relaciones de T. dimidiata con su hábitat, así como el empoderamiento de la comunidad, contribuyen al desarrollo de sistemas de control efectivos y perdurables. El propósito de esta revisión fue describir la distribución, los factores de riesgo, la ecología, las características entomológicas y los hábitats de las poblaciones de T. dimidiata en Colombia, y proponer alternativas de intervención acordes con las características particulares de esta especie.

ABSTRACT Triatoma dimidiata is an important vector of Chagas disease in Central America and countries of northern South America. In Colombia, it has a wide geographical distribution with reported presence in 14 departments in the Andean, Caribbean, Eastern plains and Upper Magdalena regions, where it occupies different natural and artificial ecotopes. The species is considered a secondary vector in the transmission of Trypanosoma cruzi. Its presence in wild, peridomestic and intradomiciliary habitats in the Andean region, coupled with its ability to move between them, has allowed it to escape the control based on pyrethroids spraying, highlighting its importance in maintaining transmission of the parasite through the potential reinfestation of homes. Understanding the relation of T. dimidiata and its habitats, as well as the empowerment of communities, will contribute to the development of effective and lasting control systems. The purpose of this review was to describe the distribution, risk factors, ecology, entomological features and habitats of T. dimidiata populations in Colombia, and to propose alternative interventions in agreement with the specific characteristics of the species.

[Triatoma dimidiata in Colombia: Distribution, ecology and epidemiological importance].

Triatoma dimidiata is an important vector of Chagas disease in Central America and countries of northern South America. In Colombia, it has a wide geographical distribution with reported presence in 14 departments in the Andean, Caribbean, Eastern plains and Upper Magdalena regions, where it occupies different natural and artificial ecotopes. The species is considered a secondary vector in the transmission of Trypanosoma cruzi. Its presence in wild, peridomestic and intradomiciliary habitats in the Andean region, coupled with its ability to move between them, has allowed it to escape the control based on pyrethroids spraying, highlighting its importance in maintaining transmission of the parasite through the potential reinfestation of homes.Understanding the relation of T. dimidiata and its habitats, as well as the empowerment of communities, will contribute to the development of effective and lasting control systems.The purpose of this review was to describe the distribution, risk factors, ecology, entomological features and habitats of T. dimidiata populations in Colombia, and to propose alternative interventions in agreement with the specific characteristics of the species.

Comportamiento de los parámetros hemodinámicos evaluados por el monitoreo ambulatorio de presión arterial de 24 horas / Behavior of hemodynamic parameters assessed with 24-hour ambulatory blood pressure monitoring

Resumen Objetivo: Describir el comportamiento de los parámetros hemodinámicos en un grupo de individuos sometidos al estudio de monitoreo ambulatorio de la presión arterial. Materiales y métodos: Estudio observacional descriptivo sobre el comportamiento de los parámetros hemodinámicos en el estudio de monitoreo ambulatorio de la presión arterial en un grupo de pacientes atendidos en dos instituciones de Medellín. Resultados: Se analizaron un total de 108 pacientes atendidos en el período comprendido entre septiembre de 2012 y octubre de 2013. Los promedios de la presión arterial sistólica y presión arterial diastólica en 24 horas fueron de 128.34 ± 12.79 mmHg y 75.87 ± 8.74 mm Hg, respectivamente. La media de la presión del pulso fue de 52.47 ± 11.12 mmHg. Las presiones arteriales medias diurna y nocturna fueron de 96,23 ± 9,5 mmHg y 85.19 ± 10,23 mmHg, respectivamente. La frecuencia cardiaca fue de 71.4 ± 10.03 latidos por minuto, para la carga sistólica la media fue de 39,38 ± 27,80% y para la carga diastólica fue de 26,26 ± 24,32%. Conclusiones: El monitoreo ambulatorio de la presión arterial es considerado actualmente como el método más confiable y exacto para el diagnóstico y evaluación de la hipertensión arterial. Permite no solo el diagnóstico y seguimiento del comportamiento de las cifras tensionales en los hipertensos, sino la evaluación de otras variables, como es mostrado en este estudio, con un comportamiento de los resultados muy similar a otros estudios locales.

Abstract Objetive: To describe the behavior of hemodynamic parameters in a group of individuals undergoing ambulatory blood pressure monitoring. Material and methods: Descriptive, observational study on the behavior of hemodynamic parameters in ambulatory blood pressure monitoring of a group of patients assisted in two institutions in Medellín. Results: A total of 108 patients were analysed, assisted between September 2012 and October 2013. Average 24-hour systolic and diastolic blood pressure values were 128.34 ± 12.79 mmHg and 75.87 ± 8,74 mmHg, respectively. Average pulse pressure was 52.47 ± 11.12 mmHg. Day and night blood pressure values were 96.23 ± 9.5 mmHg and 85.19 ± 10.23 mmHg, respectively. Heart rate was 71.4 ± 10.03 beats per minute, it was 39.38 ± 27.80% for the systolic load and 26.26 ± 24.32% for the diastolic load. Conclusions : Ambulatory monitoring of blood pressure is considered nowadays to be the most reliable and exact method for diagnosing and assessing arterial hypertension. Not only does it allow diagnosis and control of the behavior of blood pressure levels in hypertensive patients, but also assesses other variables, like the ones shown in this study, with results being similar to those of other local studies.

Cardiotoxicidad inducida por la quimioterapia desde las bases moleculares hasta la perspectiva clínica / Chemotherapy-induced cardiotoxicity from molecular bases to clinical perspective

En la actualidad, el cáncer representa una epidemia que puede ser considerada como un problema de salud pública. Es por esto que el desarrollo farmacológico ha tomado un auge en pro de mejorar las tasas de sobrevida y remisión. No obstante, esto ha sido oscurecido por la toxicidad de estas terapias. La cardiotoxicidad es un efecto adverso conocido de la terapia oncológica, que limita en muchas ocasiones una adecuada administración de regímenes con disminución de la eficacia; por esto, el entendimiento de las bases fisiopatológicas y moleculares son esenciales para determinar medidas preventivas y terapéuticas que permitan una disminución en la incidencia de la toxicidad, sin influir en la efectividad de la terapia oncológica. A continuación se realiza una revisión de los efectos adversos de la quimioterapia en el sistema cardiaco, incluyendo desde sus bases moleculares hasta sus implicaciones clínicas.

Nowadays cancer represents an epidemic that can be considered a public health problem. That is why pharmacological development has emerged for improving survival and remission rates. Nevertheless, this has been obscured by the toxicity of these therapies. Cardiotoxicity is a known adverse event of oncologic therapy that many times limits a correct regimen of administration thus lowering efficacy; therefore, understanding pathophysiological and molecular bases is essential in order to determine preventive and therapeutical measures that can allow a reduction in the incidence of toxicity, without interfering in the efficacy of the cancer therapy. We hereby describe a review of the adverse effects of chemotherapy in the cardiac system, from molecular bases to clinical implications.

Identificación de errores de medicación en un hospital de primer nivel de Pereira, Colombia / Identification of medication errors in a first level hospital of Pereira, Colombia

Resumen Antecedentes. Los errores de medicación son eventos evitables que pueden afectar la salud de los pacientes hospitalizados. Objetivo. Determinar la frecuencia de presentación de errores de medicación y las variables asociadas a su presentación en un hospital de primer nivel. Materiales y métodos. Estudio descriptivo observacional en pacientes mayores de 18 años, que se encontraron hospitalizados entre el 1 febrero y el 9 marzo de 2012 con todos los diagnósticos. Se evaluaron variables sociodemográficas, clínicas y farmacológicas a partir de las historias clínicas. Se evaluó la pertinencia de la medicación para el diagnóstico, contraindicaciones, suficiencia, frecuencia de dosificación, vía de administración, duración del tratamiento y legibilidad de los registros médicos de formulación. Resultados. Se evaluaron 96 pacientes, con edad promedio 59,7±18,8, predominio masculino (53,1%), con promedio 2,8±1,2 días de hospitalización. Los errores de medicación más frecuentes fueron: la falta de registro de duración de la formulación (97,3%), falta descripción presentación del medicamento (72,1%), falta registro vía de administración (29,9%), dosis inadecuada (9,8%), dosis insuficiente (8,2%), medicamento contraindicado (3,9%). Conclusiones. El sistema de prescripción del hospital debería ser mejorado con la incorporación de prácticas más seguras, educación médica continua, programas de alerta de interacciones y reorganización de los procedimientos de atención a los pacientes.

Summary Background. Medication errors are preventable events that may affect the health of hospitalized patients. Objective. Determine the frequency of occurrence of Medication errors and the variables that are associated with the presentation in a first level hospital. Materials and Methods. Descriptive observational study in patients older than 18 who were hospitalized between February 1 and March 9 2012 with all diagnoses. We assessed sociodemographic, clinical and pharmacological variables from medical records. We evaluated the appropriateness of the medication for the diagnosis, contraindications, sufficiency and frequency of dosing, route of administration, duration of treatment and legibility of medical records of formulation. Results. We evaluated 96 patients, average age 59.7±18.8, male predominance (53.1%), average 2.8±1.2 days of hospitalization. The most frequent medication errors were missing record of length formulation (97.3%), no description of the drug presentation (72.1%), lack registration route of administration (29.9%), inadequate dose (9.8%), insufficient dose (8.2%), medication contraindicated (3.9%). Conclusions. The hospital prescription system should be improved with the addition of safer practices, continuing medical education programs, warning of interactions and reorganization of procedures for patient care.

Use of aliskiren in Latin America in a real-world setting: aliskiren in Latin America Study (ALAS).

BACKGROUND: Hypertension (HTN) is one of the major risk factors for cardiovascular disease in Western countries, and disease control is of major relevance in order to reduce cardiovascular morbidity and mortality. Different approaches have shown efficacy, and one of the proven therapies for HTN control is the blockade of the renin-angiotensin-aldosterone system, which may be accomplished by means of various drugs with different modes of action. Aliskiren is a novel direct renin inhibitor that reduces both angiotensin I and II blood levels. Different randomized clinical trials (phase II and III) have shown its safety and efficacy either alone or in combination with hydrochlorothiazide. However, although aliskiren has been on the market for some years, reports on the post-marketing experience with aliskiren in the real-world setting are lacking. METHODS: The Aliskiren in Latin America Study (ALAS) was designed with the aim of describing the effectiveness of aliskiren at reducing blood pressure (BP) values by prospectively assessing BP control in outpatient clinics in different countries in Latin America. A total of 435 sites in 5 Latin American countries (Mexico, Ecuador, Colombia, Argentina, and Venezuela) enrolled 4588 patients who had just been initiated on aliskiren (either alone or in combination with hydrochlorothiazide) based on their treating physicians' discretion, and they were followed for a 6-month period. Prior antihypertensive drugs could be continued if their doses were not modified along the study. RESULTS: At the end of the follow-up period, a statistically significant reduction in BP values was observed, with a mean systolic BP reduction of 29.2 mmHg and a mean diastolic BP reduction of 13.78 mmHg from baseline at the 6-month visit. CONCLUSION: The BP reduction levels and the low adverse event rate demonstrate the adequate efficacy and safety profile of aliskiren (alone or with hydrochlorothiazide).

Infectious atherosclerosis: is the hypothesis still alive? A clinically based approach to the dilemma.

Among the multiple factors involved in the pathophysiology of heart disease, infections have been proposed to play a role in atherosclerosis with most of the available evidence implicating Chlamydia pneumonia, influenza virus and Mycoplasma pneumoniae. Based on a model case presentation, we speculate that in the absence of traditional risk factors and in the context of an ongoing respiratory infection caused by a pro-inflammatory pathogen (M. pneumoniae) along with a past positive serologic history for potentially proven atherogenic microorganism (C. pneumoniae) and infection may elicit potentially pathogenic events on vascular wall cells and leukocytes of atheromatous lesions, supporting the hypothesis that such infections may potentiate atherosclerotic cardiovascular disease (CVD).

Wing shape differentiation of Mepraia species (Hemiptera: Reduviidae).

Mepraia is an endemic genus found in the semiarid and arid regions of north-central Chile. Until 1998, Mepraia spinolai was the only species of the genus, distributed in coastal and interior valleys from Chile between 18° and 34°S. However, on the basis of karyotype and morphological characters, coastal desert populations between 18° and 26°S were ranked as a new species, Mepraia gajardoi. Recently, genetic studies using nuclear and mitochondrial markers on Mepraia populations suggest that the geographical criterion to separate the two species should be reviewed. Mepraia species show conspicuous alary polymorphism, unique in the Triatominae subfamily. Females of both species are invariably micropterous, while males of M. spinolai can be micropterous, brachypterous or macropterous, and only brachypterous in M. gajardoi. In this study, we use geometric morphometrics analyses to compare male wings of M. spinolai and M. gajardoi from natural populations, in order to examine if these two species have diverged in alary shape. As expected, we found that brachypterous wings of both species are smaller than macropterous wings of M. spinolai. Additionally, we detected clear differences in shape on wings of M. gajardoi and M. spinolai, not attributable to allometric effects. For last, a new alary phenotype, insects with vestigial wings, was described here for the first time. In conclusion, our analyses on wings of Mepraia species separate two distinct groups consistent with the two described species. However, our findings of vestigial wings in some coastal areas of the north part of Chile cannot rule out the existence of a hybrid zone.

[Genetic differentiation of three Colombian populations of Triatoma dimidiata (Heteroptera: Reduviidae) by ND4 mitochondrial gene molecular analysis]. / Diferenciación genética de tres poblaciones colombianas de Triatoma dimidiata (Latreille, 1811) mediante análisis molecular del gen mitocondrial ND4.

INTRODUCTION: Triatoma dimidiata is the second most important vector of Chagas disease in Colombia after Rhodnius prolixus. Population genetic studies are essential for the adequate design and implementation of vector control and surveillance strategies. OBJECTIVE: The level of genetic variability and population differentiation was surveyed among three Colombian populations of T. dimidiata from different geographic locations and ecotopes, using ND4 mitochondrial gene. MATERIALS AND METHODS: Genetic comparison was made between two wild populations from La Guajira (n=10) and Santander (n=10) provinces, and one intra (n=15) and one peridomiciliary (n=5) population from the Cesar province. The polymorphism frequencies of the ND4 mitochondrial gene sequence were analyzed to deduce population structure based on the 40 samples. RESULTS: Colombian T. dimidiata showed a high nucleotide (π: 0.034) and haplotype diversity (Hd: 0.863), as well as significant population subdivision (fST: 0.761) and a low migration rate (Nm: 0.157). Genetic distances and variability differences among populations indicate distinct population subdivision amongst the three provinces. CONCLUSION: ND4 proved useful in elucidating the significant genetic differentiation that has occurred among T. dimidiata populations from La Guajira, Cesar and Santander. The analysis suggested a relationship between population subdivision and some eco-epidemiological attributes of this vector from the central eastern and northwestern regions of Colombia.

Diferenciación genética de tres poblaciones colombianas de Triatoma dimidiata (Latreille, 1811) mediante análisis molecular del gen mitocondrial ND4 / Genetic differentiation of three Colombian populations of Triatoma dimidiata (Heteroptera: Reduviidae) by ND4 mitochondrial gene molecular analysis

Introducción. Triatoma dimidiata es el segundo vector más importante de la enfermedad de Chagas en Colombia, después de Rhodnius prolixus. El conocimiento de la composición genética y la diferenciación de poblaciones es fundamental para el adecuado diseño e implementación de estrategias de control y vigilancia vectorial. Objetivo. Determinar el nivel de variabilidad y diferenciación genética en tres poblaciones colombianas de T. dimidiata provenientes de distintas localidades y hábitats, mediante el análisis molecular de un fragmento del gen mitocondrial ND4. Materiales y métodos. Se analizó el nivel de polimorfismo y la estructura genética de dos poblaciones silvestres de los departamentos de La Guajira (n=10) y Santander (n=10), y de una población intradomiciliaria (n=15) y peridomiciliaria (n=5) del Cesar. Para tal fin, se analizaron las secuencias de nucleótidos de un fragmento del gen mitocondrial ND4. Resultados. T. dimidiata en Colombia demostró tener gran diversidad genética, tanto a nivel de nucleótidos (π: 0,034) como de haplotipo (Hd: 0,863), además de una significativa estructuración de población (fST: 0,761) con un bajo número de migrantes (Nm: 0,157). Las distancias genéticas y las diferencias en los niveles de variabilidad genética entre las tres poblaciones fueron coherentes con una posible subdivisión de población.Conclusión. Este trabajo demostró diferenciación genética entre las poblaciones de T. dimidiata de La Guajira, Cesar y Santander. Se sugiere una posible relación entre tal subdivisión y algunas características eco-epidemiológicas que posee T. dimidiata en el centro-oriente y en el norte de Colombia. Finalmente, este trabajo describe, por primera vez, la utilidad del ND4 como un marcador molecular para el estudio de poblaciones naturales de T. dimidiata.

Introduction. Triatoma dimidiata is the second most important vector of Chagas disease in Colombia after Rhodnius prolixus. Population genetic studies are essential for the adequate design and implementation of vector control and surveillance strategies. Objective. The level of genetic variability and population differentiation was surveyed among three Colombian populations of T. dimidiata from different geographic locations and ecotopes, using ND4 mitochondrial gene. Materials and methods. Genetic comparison was made between two wild populations from La Guajira (n=10) and Santander (n=10) provinces, and one intra (n=15) and one peridomiciliary (n=5) population from the Cesar province. The polymorphism frequencies of the ND4 mitochondrial gene sequence were analyzed to deduce population structure based on the 40 samples. Results. Colombian T. dimidiata showed a high nucleotide (π: 0.034) and haplotype diversity (Hd: 0.863), as well as significant population subdivision (fST: 0.761) and a low migration rate (Nm: 0.157). Genetic distances and variability differences among populations indicate distinct population subdivision amongst the three provinces. Conclusion. ND4 proved useful in elucidating the significant genetic differentiation that has occurred among T. dimidiata populations from La Guajira, Cesar and Santander. The analysis suggested a relationship between population subdivision and some eco-epidemiological attributes of this vector from the central eastern and northwestern regions of Colombia.

Triatominos (Hemiptera: Reduviidae) de la sierra nevada de santa marta, colombia. Aspectos epidemiológicos, Entosmológicos y de distribución / Triatominae (Hemiptera: Reduviidae) in the Sierra Nevada of Santa Marta, Colombia. Epidemiological, entomological and distributional aspects

Se coleccionaron 207 insectos pertenecientes a cinco especies: Triatoma maculata, Panstrongylus geniculatus, Rhodnius prolixus, T. dimidiata y R. pallescens. R. prolixus y T. dimidiata fueron las especies con los indicadores entomológicos de infestación de viviendas, colonización, dispersión e infección triatomínica más importantes; así mismo predominaron en todas las colecciones, considerándose las especies con mayor importancia epidemiológica en la zona de estudio. El 82% de todas las especies de triatominos fueron capturados en ambientes intradomiciliarios. Adicionalmente, se amplía la distribución geográfica de R. pallescens. Conclusiones: Estos hallazgos sumados a la alta seroprevalencia para T. cruzi en la región, permiten concluir que la Sierra Nevada de Santa Marta es una zona de alto riesgo de transmisión de la enfermedad de Chagas.

Objective: To describe tne entomological indexes and epidemiological importance of triatomines (Hemiptera: Reduviidae) of tne north and east slope of Santa Marta's Sierra Nevada. Colombia. Methods: Cross-sectional descriptive study. Sampling was done in 196 indigenous nuts of seven towns. Triatomines collections were done inside nouses and in peridomestic areas. Results: A total of 207 triatomines belonging to five species: Triatoma maculata, Panstrongylus geniculatus, Rnodnius prolixus. T. dimidiata and R. pallescens. was collected. R. prolixus and T. dimidiata was the species witn tne most important entomological indexes of house infestation, colonization, dispersion and infection predominating in all collections, and are considered the most epidemiological important species in the area. 82% of all triatomine species were collected inside houses. Additionally, geographical distribution of R. pallescens is extended. Conclusions: Present reports plus high prevalence found in the zone allow us to conclude that Santa Martas' Sierra Nevada is of high risk for Chaga's disease transmission.

Growth changes in Rhodnius pallescens under simulated domestic and sylvatic conditions.

Rhodnius pallescens Barber 1932 is a silvatic species of Triatominae living in palm trees in Colombia and part of Central America. In Colombia, the species did not adapt to domestic structures and is not considered as an important vector for humans. In Panama, Costa Rica and Nicaragua it is a recognized vector adapting to peridomestic and domestic structures. The main condition required for a Triatominae to be a significant vector of Chagas disease is its ability to colonize human dwellings. The mechanisms of this process are unknown. In this adaptation to domesticity, previous authors have reported a fairly constant reduction in general size and discussed its possible causes in terms of natural selection across various generations or of simple growth changes within one single generation. Some authors suggested that this size change could correspond to the relaxation of a selective pressure in the wild, where larger phenotypes are possibly selected due to their greater capacity to resist temporary food shortages. Others suggested that growth patterns could change quickly in domestic conditions because of faster development time or higher population density. Up to now, these hypotheses have not been explored experimentally. We built a laboratory protocol measuring the effects of population density and feeding patterns on the growth of R. pallescens. A total of 320 first instar nymphs from a 10 generations old laboratory colony were randomly subdivided into four regimes combining density and feeding frequency variation. Using geometric morphometric techniques applied to the emerging adults, we evaluated size and shape variation of the heads and the wings across the four experimental designs. The regimes tentatively paralleled changes occurring for a Triatominae in the transition from silvatic (low population density, low feeding frequency) to domestic (higher density, higher feeding frequency) habitats. Density and feeding frequency combined their effect within the span of one single generation to produce similar size changes for wings and heads, but significant only for the wings. No significant variation could be detected for shape variation, neither for the wing nor for the head. Our data suggest that selection is not needed to account for observed changes between sylvatic and domestic ecotopes, and they did not agree with an effect of development time on size. They highlighted the importance of the interaction between population density and feeding frequency to produce specific and significant variation in the insect dimensions.

[Differentiation by geometric morphometrics among 11 Anopheles (Nyssorhynchus) in Colombia]. / Discriminación por morfometría geométrica de once especies de Anopheles (Nyssorhynchus) presentes en Colombia.

INTRODUCTION: The correct identification of the Anopheles species of the subgenus Nyssorhynchus is important because this subgenus includes the main malaria vectors in Colombia. This information is necessary for focusing a malaria control program. OBJECTIVE: Geometric morphometrics were used to evaluate morphometric variation of 11 species of subgenus Nyssorhynchus present in Colombia and to distinguish females of each species. Materials and methods. The specimens were obtained from series and family broods from females collected with protected human hosts as attractants. The field collected specimens and their progeny were identified at each of the associated stages by conventional keys. For some species, wild females were used. Landmarks were selected on wings from digital pictures from 336 individuals, and digitized with coordinates. The coordinate matrix was processed by generalized Procrustes analysis which generated size and shape variables, free of non-biological variation. Size and shape variables were analyzed by univariate and multivariate statistics. RESULTS: The subdivision of subgenus Nyssorhynchus in sections is not correlated with wing shape. Discriminant analyses correctly classified 97% of females in the section Albimanus and 86% in the section Argyritarsis. In addition, these methodologies allowed the correct identification of 3 sympatric species from Putumayo which have been difficult to identify in the adult female stage. CONCLUSION: The geometric morphometrics were demonstrated to be a very useful tool as an adjunct to taxonomy of females the use of this method is recommended in studies of the subgenus Nyssorhynchus in Colombia.