Does urbanisation lead to parallel demographic shifts across the world in a cosmopolitan plant?

Urbanisation is occurring globally, leading to dramatic environmental changes that are altering the ecology and evolution of species. In particular, the expansion of human infrastructure and the loss and fragmentation of natural habitats in cities is predicted to increase genetic drift and reduce gene flow by reducing the size and connectivity of populations. Alternatively, the 'urban facilitation model' suggests that some species will have greater gene flow into and within cities leading to higher diversity and lower differentiation in urban populations. These alternative hypotheses have not been contrasted across multiple cities. Here, we used the genomic data from the GLobal Urban Evolution project (GLUE), to study the effects of urbanisation on non-adaptive evolutionary processes of white clover (Trifolium repens) at a global scale. We found that white clover populations presented high genetic diversity and no evidence of reduced Ne linked to urbanisation. On the contrary, we found that urban populations were less likely to experience a recent decrease in effective population size than rural ones. In addition, we found little genetic structure among populations both globally and between urban and rural populations, which showed extensive gene flow between habitats. Interestingly, white clover displayed overall higher gene flow within urban areas than within rural habitats. Our study provides the largest comprehensive test of the demographic effects of urbanisation. Our results contrast with the common perception that heavily altered and fragmented urban environments will reduce the effective population size and genetic diversity of populations and contribute to their isolation.

Experimental Crosses Between Two Dung Beetle Lineages Show Transgressive Segregation in Physiological Traits.

Physiological traits in insects are intrinsically related to their behavior, fitness, and survival and can reflect adaptations to ecological stressors in different environments, leading to population differentiation that may cause hybrid failure. In this study, we characterized five physiological traits related to body condition (body size, body mass, amount of fat, total hemolymph protein, and phenoloxidase activity) in two geographically separated and recently differentiated lineages of Canthon cyanellus LeConte, 1859 within their natural distribution in Mexico. We also performed experimental hybrid crosses between these lineages to better understand the differentiation process and explore the presence of transgressive segregation over physiological traits in them. We found differences between lineages in all traits except body mass, suggesting selective pressures related to different ecological pressures. These differences were also apparent in the transgressive segregation of all traits in F1 and F2 hybrids, except for phenoloxidase activity. Protein content was sexually dimorphic in both parental lineages but was reversed in hybrids, suggesting a genetic basis for the differences between sexes. The negative sign of transgressive segregation for most traits indicates that hybrids would be smaller, thinner, and generally unfit. Our results suggest that these two lineages may undergo postzygotic reproductive isolation, confirming the cryptic diversity of this species complex.

Digital Reconstructions Using Linear Regression: How Well Can It Estimate Missing Shape Data from Small Damaged Areas?

Skeletal remains analyzed by anthropologists, paleontologists and forensic scientists are usually found fragmented or incomplete. Accurate estimations of the original morphologies are a challenge for which several digital reconstruction methods have been proposed. In this study, the accuracy of reconstructing bones based on multiple linear regression (RM) was tested. A total of 150 digital models from complete zygomatics from recent past populations (European and African American) were studied using high-density geometric morphometrics. Some landmarks (i.e., 2, 3 and 6) were coded as missing to simulate incomplete zygomatics and the missing landmarks were estimated with RM. In the zygomatics, this simulated damage affects a few square centimeters or less. Finally, the predicted and original shape data were compared. The results indicate that the predicted landmark coordinates were significantly different from the original ones, although this difference was less than the difference between the original zygomatic and the mean zygomatic in the sample. The performance of the method was affected by the location and the number of missing landmarks, with decreasing accuracy with increasing damaged area. We conclude that RM can accurately estimate the original appearance of the zygomatics when the damage is small.

Global urban environmental change drives adaptation in white clover.

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale.

Principales técnicas quirúrgicas para el médico general / Main surgical techniques for the general practitioner

Existen múltiples técnicas y procedimientos quirúrgicos en la práctica clínica que todo médico general debería conocer y manejar ante una situación de urgencia que involucre la resolución inmediata. El no actuar en una situación emergente, ya sea por inexperiencia o desconocimiento puede poner en riesgo la vida del paciente. Entre estos procedimientos, podemos encontrar las suturas (y sus distintos tipos), la paracentesis, la apendicectomía (abierta y laparoscópica), la punción lumbar y la cesárea. Es por esto que se creó este artículo de educación médica utilizando un método explicativo de las principales técnicas quirúrgicas de forma resumida y concisa, basado en la literatura disponible, con el fin de servir como guía de bolsillo y revisión rápida para estudiantes, internos y médicos que deben enfrentarse a un procedimiento quirúrgico que no puede ser diferido.

There are multiple surgical techniques and procedures in the day to day clinical practice that every general practitioner should know how to do and handle in an emergency situation that requires immediate resolution. Failure to act in an emergent situation, either due to inexperience or ignorance, can put a patient's life at risk. Between these procedures there are sutures (and its variations), paracentesis, appendectomy (open and laparoscopic), lumbar puncture and cesarean delivery. That is why this medical education article was developed using an explicative method of the main surgical techniques in a summarized and concise way, based on the available literature, in order to serve as a pocket guide and quick review for students, interns and doctors who must face a surgical procedure that cannot be deferred.

Effect of Chemical Pollution and Parasitism on Heat Tolerance in Dung Beetles (Coleoptera: Scarabaeinae).

Ecosystem services provided by insects are threatened by recent increasing global temperatures, particularly in the tropics, where insects live close to their thermal limits. Given that tolerance to high temperatures depends on individual metabolism and physiological stress response, it may also be sensitive to other stressors that are common in natural and human-modified environments, such as pollution and parasite pressure. The effects of multiple stressors could be synergistic and can be particularly relevant in insects that provide highly valuable ecosystem services, such as dung beetles in cattle pastures. Here we measured heat tolerance (critical thermal maximum, CTmax) in dung beetles exposed to ivermectin, a toxic parasiticide excreted in cattle dung, with known negative effects on coprophagous fauna, and in beetles exposed to an immune challenge. We also exposed a group of beetles to a combination of both ivermectin and immune challenge to test for potential synergistic effects of both stressors. Contrary to our predictions, CTmax did not change with ivermectin exposure, but increased in immune-challenged beetles. As found in other insects, CTmax was higher in larger beetles, highlighting the importance of body size on thermal tolerance in ectotherms. We discuss potential mechanisms responsible of increased heat tolerance in immune-challenged beetles and highlight the importance of natural and human-induced environmental pressures that now interact with global warming and threaten ecosystem services provided by wild animals.

Insights into the genetic architecture of sexual dimorphism from an interspecific cross between two diverging Silene (Caryophyllaceae) species.

The evolution of sexual dimorphism in species with separate sexes is influenced by the resolution of sexual conflicts creating sex differences through genetic linkage or sex-biased expression. Plants with different degrees of sexual dimorphism are thus ideal to study the genetic basis of sexual dimorphism. In this study we explore the genetic architecture of sexual dimorphism between Silene latifolia and Silene dioica. These species have chromosomal sex determination and differ in the extent of sexual dimorphism. To test whether QTL for sexually dimorphic traits have accumulated on the sex chromosomes and to quantify their contribution to species differences, we create a linkage map and performed QTL analysis of life history, flower and vegetative traits using an unidirectional interspecific F2 hybrid cross. We found support for an accumulation of QTL on the sex chromosomes and that sex differences explained a large proportion of the variance between species, suggesting that both natural and sexual selection contributed to species divergence. Sexually dimorphic traits that also differed between species displayed transgressive segregation. We observed a reversal in sexual dimorphism in the F2 population, where males tended to be larger than females, indicating that sexual dimorphism is constrained within populations but not in recombinant hybrids. This study contributes to the understanding of the genetic basis of sexual dimorphism and its evolution in Silene.

Energy storage, body size and immune response of herbivore beetles at two different elevations in Costa Rica

The physiological condition and immune responses of organisms living at different elevations are expected to display local adaptations to the different climatic and biotic conditions. Small ectotherms with specialized diets are highly susceptible to environmental change, as their life cycle is largely affected by temperature and by the presence of specific resources. This study focuses on two species of rolled-leaf beetles (Chrysomelidae), both present at two different elevations in Costa Rica: Cephaloleia belti Baly, a diet-generalist, and Chelobasis bicolor Gray, a diet-specialist. Body size, energetic condition (lipid storage), muscle mass and immune condition (melanization response) were compared in beetle populations from a tropical rainforest (50 m elevation) and a tropical montane forest (2 000 m elevation). These measurements reflect current and past nutritional condition and hence are good estimators of individual fitness. We analyzed a total of 172 individuals from both species, sexes and elevations. We predicted that beetles at higher elevation would display larger body size, higher energetic condition and lower immune response associated with metabolic requirements and parasitic pressure in colder temperatures. In general, beetles at high altitude were larger, had more lipids and muscle and showed stronger melanization (i.e., immune response) than beetles at low altitudes. Such differences among populations at different elevations may reflect local adaptation to altitude or phenotypic plasticity. However, the effect of elevation was not equivalent amongst species or sex. Measuring physiological traits in organisms with broad elevational distributions could be useful in understanding possible species responses to climate change.

La condición fisiológica y la respuesta inmune de poblaciones que habitan a distintas altitudes pueden mostrar adaptación local a las condiciones abióticas y bióticas locales. Entre los organismos más susceptibles al cambio ambiental están los ectotermos pequeños con dietas especializadas, debido a que su ciclo de vida es, en gran medida, afectado tanto por la temperatura como por la presencia de recursos específicos. Este estudio se enfoca en dos especies de escarabajos (Chrysomelidae) presentes a lo largo de un gradiente altitudinal en Costa Rica: Cephaloleia belti Baly, una especie de dieta generalista, y Chelobasis bicolor Gray, de dieta especialista. Se comparó el tamaño corporal, la condición energética (almacenamiento de lípidos), la masa muscular y la condición inmunológica (respuesta de melanización) entre poblaciones de escarabajos de un bosque tropical (a 50 m de altitud) y un bosque tropical montano (a 2 000 m de altitud). Las variables seleccionadas reflejan las condiciones nutricionales actuales y pasadas y son buenos estimadores de la adecuación individual. Se analizaron un total de 172 escarabajos de ambas especies, sexos y elevaciones. Predecimos que los escarabajos a mayor elevación tendrán mayor tamaño corporal, mayor condición energética y menor respuesta inmune asociadas con los requerimientos metabólicos y la presión de los parásitos asociados con ambientes fríos. En general, los escarabajos a mayor altitud fueron más grandes, tuvieron más lípidos y masa muscular, y presentaron una mayor respuesta inmune de melanización que los escarabajos a menor altitud. Es posible que las diferencias entre las poblaciones a diferentes altitudes reflejen adaptaciones locales a las condiciones ambientales a distintas altitudes o plasticidad fenotípica. Sin embargo, el efecto de la altitud no fue de la misma magnitud entre las dos especies ni entre los dos sexos. La medición de caracteres fisiológicos en organismos ectotérmicos de amplia distribución altitudinal puede ser útil para entender las respuestas de ciertas especies al cambio climático.

A comparison of Kato-Katz technique to three other methods for diagnosis of Amphimerus spp. liver fluke infection and the prevalence of infection in Chachi Amerindians of Ecuador.

BACKGROUND: Recently, a high prevalence of infection by the liver fluke Amphimerus spp. has been documented in the Chachi Amerindians of Ecuador. For diagnosis, no studies exist that compare the sensitivity of different coproparasitological detection techniques. The present study compares the Kato-Katz technique with three other coproparasitological methods for detecting eggs of Amphimerus in stools, as well as determines the prevalence of infection in Chachi residents in a Tropical rain forest area in the northwest coast of Ecuador. METHODOLOGY/RESULTS: A total of 105 samples, utilizing the Kato-Katz technique (KK), the spontaneous sedimentation technique in tube (SSTT), the formalin-ether concentration technique (FEC), and direct smear microscopy (DM), were examined. Combining the four methods (fixed "gold" standard), 38 samples were positive with a prevalence of infection of 36.2%. The sensitivities of individual methods were 71%, 58%, 50% and 3% for KK, SSTT, FEC, and DM respectively. Our results indicated that KK alone had the best performance, detecting 27 (71%) of the 38 positive samples. The combination of KK and SSTT detected amphimeriasis in 36 (95%) samples, and KK and FEC in 31 (82%) samples. CONCLUSIONS: DM showed the lowest sensitivity, which raises concern for its value, because it is the standard technique for stool examination for detection of parasites in both public and private laboratories in Ecuador. SSTT alone detected eggs in 22 samples (58%) and would be recommended for field studies because of its simplicity. Performing two techniques on a single sample enhances the detection of Amphimerus infection. Its sensitivity is relative to a fixed "gold" standard, determined as the combined results of the four techniques performed. This study confirms the high prevalence of human infection by Amphimerus in the indigenous Chachi group where the first human cases were described.

Antecedentes de adherencia a tratamiento en pacientes hipertensos de un centro de salud chileno / History of adherence to treatment in hypertensive patients of a chilean health center / Antecedentes de aderência a tratamento em pacientes hipertensos dum centro de saúde chileno

Objetivo: Esta investigación se propuso analizar el rol predictor de variables sociodemográ cas, antecedentes de salud, autoe cacia y estrés en la adherencia a tratamiento de pacientes con hipertensión arterial de un centro de salud de atención primaria chileno. Materiales y Método: Estudio de abordaje cuantitativo de tipo correlacional realizado desde marzo a agosto del 2017. La muestra estuvo constituida por 141 pacientes hipertensos, seleccionada de forma aleatoria e intencionada. Se crearon instrumentos para recoger información sociodemográ ca y antecedentes de salud, y se utilizaron las escalas Cuestionario de Conductas de Salud de Miller, SEMCD-S del Stanford Patient Education Research Center y subescala de estrés del DASS-21 de Lovibond y Lovibond para medir adherencia, autoe cacia y estrés respectivamente. Para el análisis de datos se utilizaron medidas de tendencia central y dispersión, comparación entre grupos, análisis de correlación y regresión lineal múltiple con apoyo de los programas SPSS versión 21 y R. Resultados: La adherencia total se relacionó de manera débil pero signi cativa con autoe cacia (r=, 224) y de manera negativa con estrés (r=-,170*). La edad, el no consumo de cigarrillos y el conocimiento de que la enfermedad es una condición crónica resultaron ser predictoras de adherencia al tratamiento. Conclusión: Los resultados refuerzan la importancia de variables personales como predictoras de conductas de salud y el rol de la información y educación en la adherencia al tratamiento de personas con hipertensión. Se exploran las implicancias prácticas de estos hallazgos para el funcionamiento del programa cardiovascular.

Objective: This research aimed to analyze the predictive role of sociodemographic and health variables, self-ef cacy and stress in adherence to the treatment of patients with hypertension of a cardiovascular program at a Chilean primary care health center. Materials and Methods: A quantitative correlational study carried out from March to August 2017. The sample consisted of 141 hypertensive patients selected randomly and intentionally. The instruments to collect sociodemographic information and health antecedents were developed, and the Miller Health Behavior Questionnaire, SEMCD-S from the Stanford Patient Education Research Center and Lovibond and Lovibond DASS-21 stress subscale were applied to measure adherence, self-ef cacy and stress respectively. For data analysis, measures of central tendency and dispersion, comparison between groups, correlation analysis and multiple linear regression were used with the support of the SPSS software version 21 and R. Results: Total adherence was weakly though signi cantly related to self-ef cacy (r =, 224) and negatively related to stress (r = -, 170). Age, non- consumption of cigarettes and knowledge that the disease is a chronic condition turned out to be predictors of adherence to treatment. Conclusion: The results reinforce the importance of personal variables as predictors of health behaviors and the role of information and education in adherence to the treatment of people with hypertension. The practical implications of these ndings for the functioning of the cardiovascular program are explored.

Objetivo: Esta pesquisa se propôs analisar o rol preditor de variáveis sociodemográ cas, antecedentes de saúde, autoe cácia e estresse na aderência ao tratamento de pacientes com hipertensão arterial dum centro de saúde de atenção primária chileno. Materiais e Métodos: Estudo de abordagem quantitativo de tipo correlacional realizado desde março a agosto de 2017. Amostra Esteve constituída por 141 pacientes hipertensos, selecionada de forma aleatória e intencionada. Criaram se instrumentos para recolher informação sociodemográ cas e antecedentes de saúde, e se utilizaram as escalas Questionário de Condutas de Saúde de Miller, SEMCD-S do Stanford Patient Education Research Center e subescala de estresse do DASS-21 de Lovibond e Lovibond para medir aderência, auto- e cácia e estresse respectivamente. Para o analise de dados se utilizaram medidas de tendência central e dispersão, comparação entre grupos, analise de correlação e regressão lineal múltiple com apoio dos programas SPSS versão 21 e R. Resultados: A aderência total se relacionou de maneira fraca, mas signi cativa com auto- e cácia (r=, 224) e de maneira negativa com estresse (r=-,170*). A idade, no consumo de cigarros e o conhecimento do que a doença é uma condição crônica resultaram ser antecedentes de aderência ao tratamento. Conclusão: Os resultados reforçam a importância de variáveis pessoais como antecedentes de condutas de saúde e o rol da informação e educação na aderência ao tratamento de pessoas com hipertensão. Exploram-se as implicâncias práticas destes descobrimentos para o funcionamento do programa cardiovascular.

Hybridization and differential introgression associated with environmental shifts in a mistletoe species complex.

Host specialization after host shifting is traditionally viewed as the pathway to speciation in parasitic plants. However, geographical and environmental changes can also influence parasite speciation, through hybridization processes. Here we investigated the impact of past climatic fluctuations, environment, and host shifts on the genetic structure and patterns of hybridization and gene flow between Psittacanthus calyculatus and P. schiedeanus, a Mesoamerican species complex. Using microsatellites (408 individuals), we document moderate genetic diversity but high genetic differentiation between widespread parental clusters, calyculatus in dry pine-oak forests and schiedeanus in cloud forests. Bayesian analyses identified a third cluster, with admixture between parental clusters in areas of xeric and tropical dry forests and high levels of migration rates following secondary contact. Coincidently host associations in these areas differ from those in areas of parental species, suggesting that past hybridization played a role in environmental and host shifts. Overall, the observed genetic and geographic patterns suggest that these Psittacanthus populations could have entered a distinct evolutionary pathway. The results provide evidence for highlights on the importance of the Pleistocene climate changes, habitat differences, and potential host shifts in the evolutionary history of Neotropical mistletoes.

Trans-generational effects of ivermectin exposure in dung beetles.

Ivermectin is a powerful antiparasitic drug commonly used in cattle. Ivermectin residues are excreted in dung, threatening non-target coprophagous fauna such as dung beetles. This can have severe ecological and economic consequences for dung degradation and soil fertility. Even though the negative effects of direct ivermectin exposure on dung-degrading organisms are well known, effects could extend across generations. Here, we tested the effects of paternal or maternal exposure to ivermectin on offspring in the dung beetle Euoniticellus intermedius. This species is a classic study subject in ecotoxicology and sexual selection because males have a cephalic horn that is under intense selection via male-male competition. After confirming a negative effect of ivermectin on the number of emerged beetles, we found trans-generational effects of ivermectin exposure on the horn size of male offspring. Surprisingly however, this trans-generational effect only occurred when only the father was exposed. We detected no trans-generational effects of ivermectin exposure on offspring number, sex ratio or body size. Our results confirm that ivermectin not only has a strong effect on exposed individuals but also in their progeny. Our study opens new questions about the mechanisms responsible for parental effects and their long-term fitness consequences in contaminated habitats.

Support for the immunocompetence handicap hypothesis in the wild: hormonal manipulation decreases survival in sick damselflies.

The immunocompetence handicap hypothesis (ICHH) states that hormones enhance sexual trait expression but impair immunity. Previous tests of the ICHH have been hampered by experimental design problems. Here, we report on an experimental test of the ICHH that includes manipulations of both hormones and infections in males of the territorial damselfly, Hetaerina americana, with accurate survival measurements. We conducted a fully factorial experiment subjecting each individual to one of three topical treatments: methoprene (a juvenile hormone analog), acetone, or control, and one of three injection treatments: bacteria, PBS, or control. We measured survival of manipulated males in both the wild and in captivity. As predicted, survival was most heavily impaired in methoprene-bacteria males than in the other groups in the wild, and no survival differences emerged in captive animals. This result confirms that survival is one cost an animal pays for increased hormonal levels. This corroborates theoretical predictions of the ICHH.

Validación del Cuestionario de Salud del Paciente como herramienta de tamizaje para trastornos por somatización / Validation of the Patient Health Questionnaire like screening tool for somatization disorders

El objetivo del trabajo realizado fue evaluar la utilidad del “Cuestionario de Salud del Paciente” como posible instrumento de tamizaje para Trastornos por somatización. La metodología consistió en la validación de lenguaje del instrumento, mediante su traducción doble ciego. Posteriormente se realizó su validación de contenido con un panel de expertos. El cuestionario fue aplicado en una muestra aleatoria de100 personas en la atención primaria de salud del Hospital El Pino. Se aplicó de forma anónima y se excluyeron los síntomas de los pacientes producidos por enfermedades médicas ya diagnosticadas previamente. Al analizar los resultados se constató una sospecha de un 34,15 por ciento para trastornos por somatización según el “cuestionario de salud del paciente”, la cual sería 12 veces mayor a la indicada con los criterios del CIE-10 y casi 4 veces mayor que la indicada por los criterios de Escobar. Esto podría explicarse porque los síntomas pesquisados por el cuestionario se deban a otras enfermedades orgánicas o psiquiátricas, que no se discriminan bien por esta herramienta, o a errores en su aplicación.

The objective of the work performed was to evaluate the usefulness of the “Patient Health Questionnaire” as a possible somatization disorders screening tool. The methodology consisted in validating the language of the instrument, using a double blind translation. Then the questionnaire was presented to health professionals who gave us their impressions. The questionnaire was applied to a random sample of 100 people at the primary attention health service of Hospital El Pino. It was applied anonymously, and the symptoms of patients caused by medical diseases previously diagnosed were excluded. When the results were analyzed , a suspicion of 34.15 percent in somatization disorders was found according to the “patient health questionnaire”, which would be 12 times greater than that indicated in the criteria of the CIE-10, and almost 4 times greater than the one indicated by the criteria of Escobar. This could be explained if the symptoms investigated were caused by other organic or psychiatric diseases, that had not been discriminated by this tool or errors in its application.

[Stunned myocardium after acute ischemic stroke]. / Atontamiento miocárdico luego del accidente cerebrovascular isquémico.

The so-called stunned myocardium, defined as transitory myocardial contractile dysfunction, has been clearly demonstrated in diverse clinical situations. However, stunned myocardium related to ischemic stroke has been poorly identified. We describe two patients with diagnosis of acute ischemic stroke who developed eletrocardiographic changes, cardiac enzyme increasing levels and myocardial dysfunction secondary to abnormal cardiac wall motion. At the same time the patients developed acute lung injury with rapid resolution, perhaps as a consequence of neurocardiogenic components.

Atontamiento miocardico luego del accidente cerebrovascular isquemico / Stunned myocardium after acute ischemic stroke

El atontamiento miocárdico, definido como una disfunción contráctil transitoria del miocardio, ha sido demostrado claramente en distintas situaciones clínicas. Sin embargo, el atontamiento miocárdico asociado a un accidente cerebrovascular isquémico ha sido escasamente notificado. Describiremos dos pacientes con diagnóstico de accidente cerebrovascular isquémico agudo que presentaron cambios electrocardiográficos, elevación enzimática y trastornos en la motilidad cardíaca, compatibles con disfunciónmiocárdica. Simultáneamente desarrollaron injuria pulmonar aguda rápidamente reversible, originada probablemente por un doble componente neuro-cardiogénico.

The so-called stunned myocardium, defined as transitory myocardial contractile dysfunction, has been clearly demonstrated in diverse clinical situations. However, stunned myocardium related to ischemic stroke has been poorly identified. We describetwo patients with diagnosis of acute ischemic stroke who developed elctrocardiographic changes, cardiac enzyme increasing levels and myocardial dysfunction secondary to abnormal cardiac wall motion. At the same time the patients developed acute lung injury with rapid resolution, perhaps as a consequence of neurocardiogenic components.