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BACKGROUND: Arterial oxygen saturation (SaO2) values are used to make clinical decisions that might change a patient's prognosis, and it has been proposed as the fifth vital sign. This study aimed to determine the variation of SaO2 at different altitudes above sea level (ASL) in healthy Mexican full-term newborns. METHODS: From July 2018 to June 2019, a cross-over study was conducted in six hospitals at different altitudes ASL in Mexico. SaO2 was measured in 4015 newborns after the first 24 h of birth and before leaving the hospital using pulse oximetry. We analyzed three groups: < 250 m ASL (group 1), 1500 m ASL (group 2), and 2250 m ASL (group 3). RESULTS: The mean SaO2 was 97.6 ± 1.8%. For group 1, mean oxygen saturation was 98.2 ± 1.9%; for group 2, 96.7 ± 1.9%, and for group 3, 96.0 ± 2.1%. A statistically significant difference was observed among the groups (p < 0.001), and this difference was higher between groups 1 and 2 (1.5%, p < 0.001). Linear regression analysis showed a decrease in oxygen saturation of 1.01% for every 1000 m ASL. CONCLUSIONS: We demonstrated a statistically significant reduction in SaO2 levels at higher altitudes. This observation can be relevant for clinical decision-making based on pulse oximetry such as critical congenital heart disease screening in Mexico, where more than half of the population lives above 1500 m ASL.
INTRODUCCIÓN: Los valores de SaO2 (saturación de oxígeno) se utilizan para la toma de decisiones clínicas que podrían cambiar el pronóstico del paciente. El objetivo de este estudio fue determinar la variación de la SaO2 en recién nacidos mexicanos a término sanos a diferentes altitudes en México. MÉTODOS: Se llevó a cabo un estudio transversal en seis hospitales situados a diferentes altitudes en México. Se determinó la SaO2 usando oximetría de pulso en 4015 recién nacidos después de las primeras 24 horas de vida, pero antes del egreso del hospital de nacimiento. Se formaron tres grupos para el análisis: grupo 1 con altitud < 250 m sobre el nivel del mar (SNM); grupo 2, altitud de 1500 m SNM y grupo 3, altitud de 2250 m SNM. RESULTADOS: El promedio de la SaO2 fue de 97.6 ± 1.8%. Para el grupo 1, la media fue 98.2 ± 1.9%, para el 2, 96.7 ± 1.9% y para el 3, 96.0 ± 2.1%. Se observó una diferencia estadísticamente significativa entre los grupos (p < 0.001), que fue mayor entre los grupos 1 y 2 (1.5%, p < 0.001). El análisis de regresión lineal mostró una reducción de 1.01% en la SaO2 por cada 1000 m SNM. CONCLUSIONES: Se demostró una disminución estadísticamente significativa de los valores de SaO2 conforme aumenta la altitud. Esto puede ser de particular relevancia en la toma de decisions clínicas basadas en la oximetría de pulso, como el tamiz neonatal cardiaco, sobre todo en México donde mas de la mitad de la población vive a una altitud superior a 1500 m SNM.
Assuntos
Altitude , Saturação de Oxigênio , Recém-Nascido , Humanos , Estudos Cross-Over , México , OximetriaRESUMO
Resumen La dilatación idiopática de la aurícula derecha (DIAD) es una malformación poco frecuente caracterizada por un crecimiento desproporcionado de la aurícula derecha en ausencia de una causa estructural o funcional que la justifique. Presentamos el caso de una paciente con DIAD con diagnóstico desde la etapa prenatal.
Abstract Idiopathic dilatation of the right atrium is a rare malformation characterized by disproportionate growth of the right atrium in the absence of a cause that justifies it. We present the case of a patient with idiopathic dilatation of the right atrium diagnosed since fetal life.
RESUMO
Idiopathic dilatation of the right atrium is a rare malformation characterized by disproportionate growth of the right atrium in the absence of a cause that justifies it. We present the case of a patient with idiopathic dilatation of the right atrium diagnosed since fetal life.
La dilatación idiopática de la aurícula derecha (DIAD) es una malformación poco frecuente caracterizada por un crecimiento desproporcionado de la aurícula derecha en ausencia de una causa estructural o funcional que la justifique. Presentamos el caso de una paciente con DIAD con diagnóstico desde la etapa prenatal.
Assuntos
Átrios do Coração , Humanos , Dilatação , Átrios do Coração/anormalidades , Dilatação PatológicaRESUMO
Additive manufacturing is fast becoming a key process to manufacture a customized design with complex geometry and one process usually employed is based on the fused filament fabrication. Up to now this method is typically employed for rapid prototyping, it is therefore their mechanical strength is lower than the components manufactured using conventional casting process. It is well known that most failures are happened under repeated loads; therefore, a functional component mandatory needs to reach endurance strength under cyclic loads. Hence, this study set out to clarify several aspects of filament fused test specimens to determine their effect on accumulated damage to then predict component life under repeated loads. In this study is considered three waveforms such as sinusoidal, triangular and square, where it is observed that the square waveform provides the most severe loads. This study therefore makes a major contribution to research on the fatigue properties of parts manufactured using fused filament by reporting their fatigue behaviour under different fatigue load conditions. It would give a better understanding to improve the mechanical prediction of PLA, thereby it might be used to manufacture a functional component instead of only a prototype or spare part.
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Abstract Background: Arterial oxygen saturation (SaO2) values are used to make clinical decisions that might change a patient's prognosis, and it has been proposed as the fifth vital sign. This study aimed to determine the variation of SaO2 at different altitudes above sea level (ASL) in healthy Mexican full-term newborns. Methods: From July 2018 to June 2019, a cross-over study was conducted in six hospitals at different altitudes ASL in Mexico. SaO2 was measured in 4015 newborns after the first 24 h of birth and before leaving the hospital using pulse oximetry. We analyzed three groups: < 250 m ASL (group 1), 1500 m ASL (group 2), and 2250 m ASL (group 3). Results: The mean SaO2 was 97.6 ± 1.8%. For group 1, mean oxygen saturation was 98.2 ± 1.9%; for group 2, 96.7 ± 1.9%, and for group 3, 96.0 ± 2.1%. A statistically significant difference was observed among the groups (p < 0.001), and this difference was higher between groups 1 and 2 (1.5%, p < 0.001). Linear regression analysis showed a decrease in oxygen saturation of 1.01% for every 1000 m ASL. Conclusions: We demonstrated a statistically significant reduction in SaO2 levels at higher altitudes. This observation can be relevant for clinical decision-making based on pulse oximetry such as critical congenital heart disease screening in Mexico, where more than half of the population lives above 1500 m ASL.
Resumen Introducción: Los valores de SaO2 (saturación de oxígeno) se utilizan para la toma de decisiones clínicas que podrían cambiar el pronóstico del paciente. El objetivo de este estudio fue determinar la variación de la SaO2 en recién nacidos mexicanos a término sanos a diferentes altitudes en México. Métodos: Se llevó a cabo un estudio transversal en seis hospitales situados a diferentes altitudes en México. Se determinó la SaO2 usando oximetría de pulso en 4015 recién nacidos después de las primeras 24 horas de vida, pero antes del egreso del hospital de nacimiento. Se formaron tres grupos para el análisis: grupo 1 con altitud < 250 m sobre el nivel del mar (SNM); grupo 2, altitud de 1500 m SNM y grupo 3, altitud de 2250 m SNM. Resultados: El promedio de la SaO2 fue de 97.6 ± 1.8%. Para el grupo 1, la media fue 98.2 ± 1.9%, para el 2, 96.7 ± 1.9% y para el 3, 96.0 ± 2.1%. Se observó una diferencia estadísticamente significativa entre los grupos (p < 0.001), que fue mayor entre los grupos 1 y 2 (1.5%, p < 0.001). El análisis de regresión lineal mostró una reducción de 1.01% en la SaO2 por cada 1000 m SNM. Conclusiones: Se demostró una disminución estadísticamente significativa de los valores de SaO2 conforme aumenta la altitud. Esto puede ser de particular relevancia en la toma de decisions clínicas basadas en la oximetría de pulso, como el tamiz neonatal cardiaco, sobre todo en México donde mas de la mitad de la población vive a una altitud superior a 1500 m SNM.
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We report an unusual case of a 2-month-old baby with a diagnosis of common arterial trunk and double outlet right ventricle with a remote type ventricular septal defect. Taking into consideration the physiologic moment and anatomic findings of the patient, we planned and successfully performed a bidirectional Glenn procedure as its first palliative procedure.
Assuntos
Dupla Via de Saída do Ventrículo Direito , Técnica de Fontan , Cardiopatias Congênitas , Persistência do Tronco Arterial , Coração Univentricular , Lactente , Humanos , Técnica de Fontan/métodos , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/cirurgia , Dupla Via de Saída do Ventrículo Direito/diagnóstico por imagem , Dupla Via de Saída do Ventrículo Direito/cirurgia , Cuidados Paliativos/métodos , Ventrículos do Coração/cirurgia , Resultado do TratamentoRESUMO
OBJETIVO: Realizar un análisis de costoefectividad de la oximetría de pulso como prueba de detección neonatal de las cardiopatías congénitas críticas (CCC) en México. Material y métodos. Se realizó un estudio de evaluación económica desde la perspectiva de los proveedores de servicios de salud. A través de un árbol de decisiones se comparó la examinación física versus la examinación física junto con la prueba de oxi-metría de pulso (POP). RESULTADOS: Por cada 10 000 recién nacidos, la alternativa con la POP detectó 32 casos adicionales de CCC, con una razón de costoefectividad incremental de 1 219 USD y una probabilidad de costoefectividad mayor a 90% con una disposición a pagar de 25 000 USD por cada detección temprana. Conclusión. La costoefectividad de la POP, como tamiz neonatal cardiaco, es mayor en México que en países de altos ingresos, y representa una inversión costoefectiva para ganar años de vida en la población infantil de México.
Assuntos
Cardiopatias Congênitas , Oximetria , Análise Custo-Benefício , Humanos , Recém-Nascido , México , Estudos RetrospectivosAssuntos
Cardiopatias , Triagem Neonatal , Diagnóstico Precoce , Cardiopatias/diagnóstico , Humanos , Recém-Nascido , MéxicoRESUMO
Harbor and coastal structures are essential in maritime connections. Additionally, some offshore structures near the coast are important for supplying energy as a material or transforming the natural resources into energy, as in wind turbines. One of the main issues that needs to be overcome in terms of these structures is mechanical fatigue due to the loads of the structure by its function and waves, wind, the current seawater level, and ice. Structural design has to meet high target loads to ensure that structures can endure extreme marine conditions under the assumption of the probability of loads and based on marine conditions, can mask damage where component immersions are not available for inspection. In this work, the wave loads and fatigue damage under random processes are reviewed.
RESUMO
Resumen Las cardiopatías congénitas (CC) se definen como una anomalía estructural del corazón o de los grandes vasos intratorácicos. Constituyen la malformación congénita más frecuente al nacimiento. Al menos un tercio de los pacientes requieren algún tipo de intervención antes del año de edad. Las manifestaciones clínicas de las cardiopatías en la etapa neonatal se presentan con un amplio contexto clínico y se pueden confundir con problemas a nivel pulmonar o infeccioso, lo que dificulta su diagnóstico y con ello contribuyendo de forma importante a la mortalidad y morbilidad de estos pacientes, ya que se retrasa el diagnóstico y manejo oportuno. El monitoreo por oximetría de pulso en el periodo neonatal se utiliza actualmente como método diagnóstico para la detección de cardiopatías congénitas críticas; a pesar de que las detecta en forma temprana, en muchos países aún no se lleva a cabo. El objetivo de este artículo es ofrecer un panorama general de la presentación clínica, aspectos diagnósticos y manejo inicial de las CC en el primer año de edad que pueda ser de utilidad a los médicos de primer contacto para mejorar la atención en este grupo de pacientes.
Abstract Congenital heart disease (CHD) is defined as a structural abnormality of the heart or large intrathoracic vessels. They constitute the most frequent congenital malformation at birth. At least one third of patients require some type of intervention before the year of age. The clinical manifestations of heart disease in the neonatal stage are presented with a wide clinical context and can be confused with problems at the pulmonary or infectious level making difficult to diagnose them and thereby contributing significantly to the mortality and morbility of these patients since the diagnosis is delayed and timely handling. Pulse oximetry monitoring in the neonatal period is currently used as a diagnostic method for the detection of critical congenital heart disease. Although it detects them early, in many countries it is not yet carried out. The objective of this article is to offer an overview of the clinical presentation, diagnostic aspect and initial management of CHD in the first year of age that may be useful to first contact physicians to improve the management of this group of patients.
RESUMO
Congenital heart disease (CHD) is defined as a structural abnormality of the heart or large intrathoracic vessels. They constitute the most frequent congenital malformation at birth. At least one third of patients require some type of intervention before the year of age. The clinical manifestations of heart disease in the neonatal stage are presented with a wide clinical context and can be confused with problems at the pulmonary or infectious level making difficult to diagnose them and thereby contributing significantly to the mortality and morbility of these patients since the diagnosis is delayed and timely handling. Pulse oximetry monitoring in the neonatal period is currently used as a diagnostic method for the detection of critical congenital heart disease. Although it detects them early, in many countries it is not yet carried out. The objective of this article is to offer an overview of the clinical presentation, diagnostic aspect and initial management of CHD in the first year of age that may be useful to first contact physicians to improve the management of this group of patients.
Las cardiopatías congénitas (CC) se definen como una anomalía estructural del corazón o de los grandes vasos intratorácicos. Constituyen la malformación congénita más frecuente al nacimiento. Al menos un tercio de los pacientes requieren algún tipo de intervención antes del año de edad. Las manifestaciones clínicas de las cardiopatías en la etapa neonatal se presentan con un amplio contexto clínico y se pueden confundir con problemas a nivel pulmonar o infeccioso, lo que dificulta su diagnóstico y con ello contribuyendo de forma importante a la mortalidad y morbilidad de estos pacientes, ya que se retrasa el diagnóstico y manejo oportuno. El monitoreo por oximetría de pulso en el periodo neonatal se utiliza actualmente como método diagnóstico para la detección de cardiopatías congénitas críticas; a pesar de que las detecta en forma temprana, en muchos países aún no se lleva a cabo. El objetivo de este artículo es ofrecer un panorama general de la presentación clínica, aspectos diagnósticos y manejo inicial de las CC en el primer año de edad que pueda ser de utilidad a los médicos de primer contacto para mejorar la atención en este grupo de pacientes.
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BACKGROUND: Although high altitude has been considered a risk factor for the Fontan operation, and an indication for fenestration, there is a paucity of data to support its routine use. Fenestration, with its necessary right to left induced shunt, together with the lower partial pressure of oxygen found with progressive altitude, can significantly decrease hemoglobin oxygen saturation, and therefore, it would be desirable to avoid it. OBJECTIVE: To analyze immediate and medium-term results of the non-fenestrated, extracardiac, Fontan procedure at high altitude. METHODS: Retrospective analysis of data from consecutive patients who underwent non-fenestrated, extracardiac, Fontan procedure at two institutions located in Mexico City at 2,312 m (7,585 ft) and 2,691 m (8,828 ft) above sea level. High altitude was not considered a risk factor. RESULTS: Thirty-nine patients were included, with a mean age of 6.7 years. Mean preoperative indexed pulmonary vascular resistance was 1.7 Wood units. Seventy-nine percent of the patients extubated in the operating room. There was one in-hospital death (2.56%) and one at follow-up. Median chest tube drainage time was 6.5 and 6 days for the right and left pleural spaces. Median oxygen saturation at discharge was 90%. At a median follow-up of six months, all survivors, except one, had good tolerance to daily life activities. CONCLUSIONS: The present study shows good short- and medium-term results for the non-fenestrated, extracardiac, Fontan operation at altitudes between 2,300 and 2,700 m and might favor this strategy over fenestration to improve postoperative oxygen saturation. Further studies to examine the long-term outcomes of this approach need to be considered.
Assuntos
Altitude , Técnica de Fontan/efeitos adversos , Cardiopatias Congênitas/cirurgia , Adolescente , Criança , Pré-Escolar , Drenagem/métodos , Feminino , Hemoglobinas , Humanos , Masculino , México , Oxigênio , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Resistência VascularRESUMO
In many butterfly species, the posterior end of the hindwings of individuals perching with their wings closed resembles a butterfly head. This "false head" pattern is considered an adaptation to deflect predator attacks to less vulnerable parts of the body. The presence of symmetrical damage in left and right wings is considered evidence of failed predator attacks to perching butterflies. In this research, we tested the prediction derived from the deflection hypothesis that the degree of resemblance of the false head area (FH) to a real head, as measured by the number of FH "components" (eyespots, "false antennae", modified outline of the FH area and lines converging on the FH area) present in the hindwings, is positively correlated to the frequency of symmetrical damage in the FH area. We studied specimens from two scientific collections of butterflies of the subfamily Theclinae (Lycaenidae) belonging to the Universidad Nacional Autónoma de México (Colección Nacional de Insectos [CNIN] and Museo de Zoología, Facultad de Ciencias [MZFC]). We scored the presence of symmetrical damage in a sample of 20,709 specimens (CNIN: 3,722; MZFC: 16,987) from 126 species (CNIN: 78 species; MZFC: 117 species; 71 species shared by both collections) whose hindwings vary in the number of FH components, and found that, as predicted, the proportion of specimens with symmetrical damage increases as the number of FH components increases. We also tested the hypothesis that behavioural differences between the sexes makes males more prone to receive predator attacks and, thus, we predicted a higher frequency of symmetrical damage in the FH of males than in that of females. We found that the frequency of symmetrical damage was not significantly different between males and females, suggesting that behavioural differences between the sexes produce no differences in the risk of being attacked. Overall, our results provide support to the idea that the FH of butterflies is an adaptation that deflects predator attacks to less vulnerable parts of the body in both sexes.
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Mortality after surgery for congenital heart disease (CHD) in Mexico is significantly higher than in high-income countries due to structural, medical, and financial factors. In Mexico, public hospitals have a large volume of patients but inadequate quality control systems, whereas private hospitals, although having higher quality control systems, have an insufficient number of patients to build programs of excellence. We describe the creation of a novel hybrid private-public program in Mexico that leverages the advantages of both sectors while establishing an integrated multidisciplinary unit that has allowed us to improve the quality of care for patients with CHD.
Assuntos
Atenção à Saúde/organização & administração , Cardiopatias Congênitas/cirurgia , Parcerias Público-Privadas , Adolescente , Criança , Pré-Escolar , Países em Desenvolvimento , Feminino , Gastos em Saúde , Hospitais Privados/organização & administração , Hospitais Públicos/organização & administração , Humanos , Lactente , Recém-Nascido , Masculino , México , Modelos Organizacionais , Qualidade da Assistência à SaúdeRESUMO
Introducción: las lesiones no intencionales o accidentes representan un problema de salud mundial. Objetivos: aplicar y evaluar una intervención comunitaria sobre factores de riesgo y accidentes en hogares de niños menores de cinco años. Métodos: se realizó un estudio de cohorte cuasi-experimental de intervención comunitaria en 122 niños y sus familias de cuatro consultorios del Policlínico-Hospital Alberto Fernández Valdés de Santa Cruz del Norte, provincia Mayabeque entre el 1ro de septiembre del 2013 y el 31 de marzo del 2014. Fueron variables: edad, factores de riesgo de accidentes, grados de riesgo de accidentes en los hogares y antecedentes de accidentes en los seis meses previos a la intervención. Se aplicó y se evaluó un cuestionario sobre accidentes y factores de riesgo al inicio del estudio y seis meses después de la intervención. Resultados: los factores de riesgo de accidentes más frecuentes en los hogares fueron: niños dejados solos, 45.0 por ciento, equipos, tomacorrientes e instalaciones eléctricas sin protección, 36.0 por ciento y acceso libre al área de la cocina 33.6 por ciento. Predominaron los hogares con bajo riesgo con el 69.7 por ciento. En el 60.6 por ciento de los niños presentaron accidentes en los seis meses previos. Los accidentes más frecuentes fueron: caídas que requirieron tratamiento médico, 22.1 por ciento, introducción de cuerpos extraños, 18.8 por ciento y quemaduras, 10.6 por ciento. Después de la intervención disminuyeron significativamente los factores de riesgo y los accidentes.Conclusiones: se considera que la intervención comunitaria fue exitosa. Se recomienda aplicar la clasificación de riesgo utilizada en el estudio y seguir realizando intervenciones con esta metodología(AU)
Introduction: non intentional lesions or accidents represent a world health. Objectives: to apply and evaluate a communitarian evaluation about risk factors and accidents of children younger than five years old at home. Methods: a cohort quasi-experimental communitarian intervention was carried out in 122 children and their families form four Doctors Offices at Alberto Fernandez Valdés policlinic-hospital in Santa Cruz del Norte, Mayabeque province from September 1st , 2013 to March 31st, 2014. The variables were: age, risk factors of accidents, risk degrees of accidents at home and antecedents of accidents in the six previous months to the intervention. A questionnaire about accidents and risk factors was applied and evaluated at the beginning of the study and after six months of applying the intervention.Results: the most frequent risk factors of accidents at home were: left alone children, 45.0 percent, equipment, and electric installation without protection, 36.0% and free access to the area of the kitchen 33.6 percent. Homes at low risks prevailed with the 69.7 percent. The 60.6 percent of the children presented accidents in the six previous months. The most frequent accidents were: falls that required medical treatments, 22.1 percent, introduction of foreign objects, 18.8 percent y burns, 10.6 percent. After the intervention the risk factors and accidents decreased significantly.Conclusions: It is considered that the communitarian intervention was successful. It is recommended the used classification of risk of the study and keep on performing interventions with this methodology(AU)
Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Acidentes , Fatores de Risco , Família , Atenção Primária à Saúde , Estudos de CoortesRESUMO
Altitudinal richness patterns of Papilionidae, Pieridae and Nymphalidae (Lepidoptera) in Mexican mountain areas. Butterflies constitute an useful group to investigate biodiversity patterns in specific geographic areas. The aim of this study was to describe the altitudinal patterns distribution and to recognize the main grouping factors of these families. We conducted a comparative study between the butterfly fauna (Papilionidae, Pieridae and Nymphalidae) of five Mexican mountain ranges (Sierra de Manantlán, Sierra de Atoyac de Alvarez, Loxicha Region, Teocelo-Xalapa and Sierra de Juárez), that included 34 sites of altitudinal ranges from 100 to 2 820m. Data was obtained from the Zoology Museum of the National University of Mexico, and comprised more than 60 000 butterfly records of 398 taxa (subspecies level) proceeding during the last 35 years. Fauna similarity between localities were analyzed using a cluster analysis by Sorensen similarity coefficient. Species richness showed a general tendency to decrease with altitude; the main difference was found between the locality with higher altitude and the rest of the sites. The principal factors affecting the identified clusters followed this order: the location in Pacific or Atlantic slope, and location on a particular mountain range. Three altitudinal levels (low elevations, up to 1 200m; intermediate elevations, from 1200 to 1800 m; and high elevations, from 1800 to 2500 m) were described in accordance to their main characteristic taxa. While Neartic elements were common in the highest altitudinal floor, Neotropical taxa were common in the lowest one. It was more difficult to characterize the intermediate level in which a high number of localities were clustered; this intermediate level was characterized by the presence of some endemic species. The results suggest that historical factors are preeminent in butterfly fauna composition in these areas. Future studies may include other Mexican mountain areas to obtain more information on the different factors (latitude, altitude, slope) influencing biodiversity patterns.
Assuntos
Biodiversidade , Borboletas/classificação , Altitude , Animais , México , Densidade DemográficaRESUMO
Butterflies constitute an useful group to investigate biodiversity patterns in specific geographic areas. The aim of this study was to describe the altitudinal patterns distribution and to recognize the main grouping factors of these families. We conducted a comparative study between the butterfly fauna (Papilionidae, Pieridae and Nymphalidae) of five Mexican mountain ranges (Sierra de Manantlán, Sierra de Atoyac de Álvarez, Loxicha Region, Teocelo-Xalapa and Sierra de Juárez), that included 34 sites of altitudinal ranges from 100 to 2 820m. Data was obtained from the Zoology Museum of the National University of Mexico, and comprised more than 60 000 butterfly records of 398 taxa (subspecies level) proceeding during the last 35 years. Fauna similarity between localities were analyzed using a cluster analysis by Sorensen similarity coefficient. Species richness showed a general tendency to decrease with altitude; the main difference was found between the locality with higher altitude and the rest of the sites. The principal factors affecting the identified clusters followed this order: the location in Pacific or Atlantic slope, and location on a particular mountain range. Three altitudinal levels (low elevations, up to 1 200m; intermediate elevations, from 1 200 to 1 800m; and high elevations, from 1 800 to 2 500m) were described in accordance to their main characteristic taxa. While Neartic elements were common in the highest altitudinal floor, Neotropical taxa were common in the lowest one. It was more difficult to characterize the intermediate level in which a high number of localities were clustered; this intermediate level was characterized by the presence of some endemic species. The results suggest that historical factors are preeminent in butterfly fauna composition in these areas. Future studies may include other Mexican mountain areas to obtain more information on the different factors (latitude, altitude, slope) influencing biodiversity patterns.
Las mariposas diurnas integran uno de los grupos más utilizados para el reconocimiento y monitoreo de la diversidad de una biota. Se realizó un estudio comparativo de las faunas de mariposas de las familias Papilionidae, Pieridae y Nymphalidae de cinco áreas montañosas de México, situadas en las vertientes Atlántico y Pacífico: las sierras de Atoyac de Álvarez, Manantlán, Juárez, y las áreas de Teocelo-Xalapa y la región Loxicha, con un total de 34 localidades representativas de los cinco transectos altitudinales, que comprenden de los 300 a los 3 100m de altitud. Se observó una tendencia general a la disminución de la riqueza con la altitud. Se analizó la similitud entre el total de localidades mediante el índice de Sørensen, diferenciándose en primer lugar las dos estaciones de elevaciones superiores (sobre los 2 500msnm), caracterizadas por pobres lepidóptero-faunas. En el grupo principal (32 sitios) las principales agrupaciones se dan de acuerdo, en primer lugar, a la pertenencia a la vertiente pacífica o atlántica, evento más histórico que ecológico y, después, las estaciones de una misma sierra o según tres diferentes pisos altitudinales, que se caracterizan de acuerdo con los táxones predominantes.