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1.
PLoS One ; 18(12): e0295738, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38100504

RESUMO

The relative importance of allochthonous and autochthonous carbon (C) as sources of energy for tropical stream food webs remains an open question. Allochthonous C might be the main energy source for small and shaded forest streams, while autochthonous C is more likely to fuel food webs draining land uses with less dense vegetation. We studied food webs in cloud forest streams draining watersheds with forests, coffee plantations, and pastures. Our goal was to assess the effects of those land uses on the C source and structure of stream food webs. The study took place in tropical montane streams in La Antigua Watershed, in eastern Mexico. We selected three streams per land use and sampled biofilm and leaf litter as the main food resources, and macroinvertebrates and aquatic vertebrates from different trophic guilds. Samples were analyzed for δ13C and δ15N isotopes. Using a Bayesian mixing model, we estimated the proportional assimilation of autochthonous and allochthonous carbon by each guild. We found that consumers were mostly using allochthonous C in all streams, regardless of watershed land use. Our findings indicate that montane cloud forest streams are dominated by allochthony even in watersheds dominated by pastures. Abundant precipitation in this life zone might facilitate the movement of allochthonous C into streams. While food webs of streams from coffee plantations and pastures also rely on allochthonous resources, other impacts do result in important changes in stream functioning.


Assuntos
Carbono , Cadeia Alimentar , Animais , Teorema de Bayes , Florestas , Biofilmes , Ecossistema
2.
Nat Commun ; 14(1): 4751, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550318

RESUMO

Cities can host significant biological diversity. Yet, urbanisation leads to the loss of habitats, species, and functional groups. Understanding how multiple taxa respond to urbanisation globally is essential to promote and conserve biodiversity in cities. Using a dataset encompassing six terrestrial faunal taxa (amphibians, bats, bees, birds, carabid beetles and reptiles) across 379 cities on 6 continents, we show that urbanisation produces taxon-specific changes in trait composition, with traits related to reproductive strategy showing the strongest response. Our findings suggest that urbanisation results in four trait syndromes (mobile generalists, site specialists, central place foragers, and mobile specialists), with resources associated with reproduction and diet likely driving patterns in traits associated with mobility and body size. Functional diversity measures showed varied responses, leading to shifts in trait space likely driven by critical resource distribution and abundance, and taxon-specific trait syndromes. Maximising opportunities to support taxa with different urban trait syndromes should be pivotal in conservation and management programmes within and among cities. This will reduce the likelihood of biotic homogenisation and helps ensure that urban environments have the capacity to respond to future challenges. These actions are critical to reframe the role of cities in global biodiversity loss.


Assuntos
Quirópteros , Urbanização , Animais , Abelhas , Síndrome , Ecossistema , Biodiversidade , Aves
3.
J Therm Biol ; 112: 103432, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36796888

RESUMO

There is strong covariation between the thermal physiology of ectothermic animals and their thermal environment. Spatial and temporal differences in the thermal environment across a species' range may result in changes in thermal preferences between populations of that species. Alternatively, thermoregulatory-based microhabitat selection can allow individuals to maintain similar body temperatures across a broad thermal gradient. Which strategy a species adopts is often dependent on taxon-specific levels of physiological conservatism or ecological context. Identifying which strategies species use in response to spatial and temporal variation in environmental temperatures requires empirical evidence, which then can support predictions as to how a species might respond to a changing climate. Here we present findings of our analyses of the thermal quality, thermoregulatory accuracy and efficiency for the lizard, Xenosaurus fractus, across an elevation-thermal gradient and over the temporal thermal variation associated with seasonal changes. Xenosaurus fractus is a strict crevice-dweller, a habitat that can buffer this lizard from extreme temperatures and is a thermal conformer (body temperatures reflect air and substrate temperatures). We found populations of this species differed in their thermal preferences along an elevation gradient and between seasons. Specifically, we found that habitat thermal quality, thermoregulatory accuracy and efficiency (all measures of how well the lizards' body temperatures compared to their preferred body temperatures) varied along thermal gradients and with season. Our findings indicate that this species has adapted to local conditions and shows seasonal flexibility in those spatial adaptations. Along with their strict crevice-dwelling habitat, these adaptations may provide some protection against a warming climate.


Assuntos
Lagartos , Animais , Lagartos/fisiologia , Estações do Ano , México , Temperatura Corporal/fisiologia , Regulação da Temperatura Corporal/fisiologia , Temperatura
4.
Artigo em Inglês | MEDLINE | ID: mdl-35627555

RESUMO

Running is a complete and accessible physical exercise for the population, but little research has been done on the psychological and environmental variables related to its practice. The objective of this research was to determine how emotional intelligence, psychological well-being, and body dissatisfaction are related to running in natural spaces for men and women. A cross-sectional study was conducted on 331 runners from 20 states of the Mexican Republic (55.3% women), between 18 and 80 years old (m = 37.4; SD = 11.5), with an average of 7 years running experience (SD = 9.3). The Brief Emotional Intelligence Inventory, the Psychological Well-Being Scale, and the Body Shape Questionnaire were used. The results show that men who run in natural spaces have greater psychological well-being and emotional intelligence (stress management) and less body dissatisfaction, and they run more days per week than those who run in built spaces. Predictors of running in natural spaces were greater psychological well-being and emotional intelligence (stress management). On the other hand, women who run in natural spaces show lower emotional intelligence (stress management) and run for more minutes per day. The predictors for running in natural spaces were identified as lower emotional intelligence (stress management), running for more minutes per day, and practicing another physical exercise. In conclusion, in this heterogeneous sample, natural environments are likely to be related to better performance and certain psychological indicators for runners. However, these relationships differ between men and women, so further studies with larger sample sizes are needed to confirm our findings.


Assuntos
Inteligência Emocional , Exercício Físico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
Angiol. (Barcelona) ; 74(1): 38-39, ene.-feb.,2022.
Artigo em Espanhol | IBECS | ID: ibc-202752

RESUMO

Introducción: el tratamiento de aneurismas complejos mediante FEVAR incluye entre sus objetivos un tiempoquirúrgico reducido para poder alcanzar el éxito técnico y clínico. Sin embargo, la canulación y el implante de losstents puente en múltiples arterias viscerales pueden suponer un factor limitante. Para evitar un tiempo de escopia y una dosis de radiación prolongados existen algunas maniobras que pueden ayudar a optimizar el tiempo de cateterización. Material y métodos: se realiza una revisión de los últimos casos tratados mediante endoprótesis fenestradas custom made de Zenith Cook® durante el año 2021 en un servicio de angiología, cirugía vascular y endovascular. El objetivo es mostrar las técnicas que sirven para optimizar el tratamiento de aneurismas complejos y que el cirujano puede emplear con el material habitual. Para ello se muestran varios fragmentos de vídeos de estos procedimientos grabados con el sistema OneView. Resultados: el primer paso clave consiste en la liberación del dispositivo fenestrado. La endoprótesis de Cook® presenta una o varias ligaduras de reducción que la mantienen fruncida hasta garantizar una correcta orientación y un correcto posicionamiento. Asimismo, ofrece la opción de canular las arterias viscerales entre la pared arterial y el dispositivo. Con una planifi cación adecuada y un abordaje sistematizado, el uso de guías coaxiales, catéteres de punta simple o reversa e introductores es esencial. El techo de la endoprótesis permite el avance de guías y de introductores con el soporte sufi ciente para su canulación. Los sistemas precargados permiten la canulación desde el miembro superior o el inferior. En este último caso, se utiliza una guía buddy de 0,014" que ofrece soporte al introductor, ya que lo acerca más aún a la fenestración, de tal modo que potencia el momento de torsión (torque) y el empuje del catéter.


Introduction: the treatment of complex aneurysms using FEVAR includes among its objectives a reduced surgicaltime in order to achieve technical and clinical success. However, cannulation and implantation of bridging stentsin multiple visceral arteries can be a limiting factor. To avoid a protracted scope time and radiation dose, there aresome maneuvers that can help optimize catheterization time. Material and methods: a review of the last cases treated with custom made Zenith Cook® fenestrated endoprostheses during the year 2021 is performed in an angiology, vascular and endovascular surgery service. The objective is to show video clips recorded with the OneView system of these techniques that the surgeon can use with the usual material to optimize the treatment of complex aneurysms.Results: the first key step is the release of the fenestrated device. The Cook® endoprosthesis has one or morereduction ligatures that keep it puckered until it guarantees correct orientation and positioning, as well as theoption of cannulating the visceral arteries between the arterial wall and the device.With proper planning and a systematic approach, the use of coaxial guides with single or reverse tip cathetersand introducers are essential. The roof of the endoprosthesis allows the advancement of guides and introducerswith sufficient support for their cannulation. The preloaded systems allow cannulation from the upper or lowerlimb. In the latter case, a 0.014” buddy guide is used to provide support for the introducer, bringing it even closerto fenestration in such a way as to enhance the torque and thrust of the catheter.


Assuntos
Humanos , Ciências da Saúde , Cateterismo/instrumentação , Artéria Gástrica , Aneurisma , Duração da Cirurgia
6.
Med Phys ; 48(11): 6567-6577, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34528262

RESUMO

PURPOSE: To measure the out-of-field mean photon energy and dose imparted by the secondary radiation field generated by 6 MV and 6 MV FFF beams using TLD-300 and TLD-100 dosimeters and to use the technique to quantify the contributions from the different sources that generate out-of-field radiation. METHODS: The mean photon energy and the dose were measured using the TLD-300 glow curve properties and the TLD-100 response, respectively. The TLD-300 glow curve shape was energy-calibrated with gamma rays from 99m Tc, 18 F, 137 Cs, and 60 Co sources, and its energy dependence was quantified by a parameter obtained from the curve deconvolution. The TLD-100 signal was calibrated in absorbed dose-to-water inside the primary field. Dosimeters were placed on the linac head, and on the surface and at 4.5 cm depth in PMMA at 1-15 cm lateral distances from a 10 × 10 cm2 field edge at the isocenter plane. Three configurations of dosimeters around the linac were defined to identify and quantify the contributions from the different sources of out-of-field radiation. RESULTS: Typical energies of head leakage were about 500 keV for both beams. The mean energy of collimator-scattered radiation was equal to or larger than 1250 keV and, for phantom-scattered radiation, mean photon energies were 400 keV for the 6 MV and 300 keV for the 6 MV FFF beam. Relative uncertainties to determine mean photon energy were better than 15% for energies below 700 keV, and 40% above 1000 keV. The technique lost its sensitivity to the incident photon energy above 1250 keV. On the phantom surface and at 1-15 cm from the field edge, 80%-90% of out-of-field dose came from scattering in the secondary collimator. At 4.5 cm deep in the phantom and 1-5 cm from the field edge, 50%-60% of the out-of-field dose originated in the phantom. At the points of measurement, the head leakage imparted less than 0.1% of the dose at the isocenter. The 6 MV FFF beam imparted 8-36% less out-of-field dose than the 6 MV beam. These energy results are consistent with general Monte Carlo simulation predictions and show excellent agreement with simulations for a similar linac. The measured out-of-field doses showed good agreement with independent evaluations. CONCLUSIONS: The out-of-field mean photon energy and dose imparted by the secondary radiation field were quantified by the applied TLD-300/TLD-100 method. The main sources of out-of-field dose were identified and quantified using three configurations of dosimeters around the linac. This technique could be of value to validate Monte Carlo simulations where the linac head design, configuration, or material composition are unavailable.


Assuntos
Fótons , Dosímetros de Radiação , Método de Monte Carlo , Aceleradores de Partículas , Imagens de Fantasmas
7.
Zookeys ; 1054: 127-153, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34393566

RESUMO

The Selva Zoque region is characterized by a great variety of ecosystems for which there is little information about reptile species diversity and their conservation status. This study is the first assessment of the species richness, composition, and conservation status of reptiles of this region. Additionally, this information is compared with that of seven other tropical regions in northern Mesoamerica. In total, 141 native reptile species belonging to 81 genera and 29 families are recorded for the Selva Zoque region. Sixty species (42% of the total) recorded in Selva Zoque are in high-risk categories according to the Mexican Ministry of the Environment, the highest number for the Mexican regions of Mesoamerica. According to the IUCN, six species are in high-risk categories, seven species are in Data Deficient, and 23 (16%) have not been evaluated yet. According to the Environmental Vulnerability Scores approach, 28 species (20%) are in the high vulnerability category. The Selva Zoque species composition is most similar to Los Tuxtlas and Lacandona regions, and most dissimilar to Sian Ka´an Biosphere Reserve. The reptilian fauna of Selva Zoque has a distinctive composition, with the highest number (11 species) of endemic reptiles in the northern Mesoamerican, and species from two biogeographic provinces: the Gulf of Mexico and the Mexican Pacific Coast. These results indicate that the Selva Zoque is the most diverse region in native reptile species in northern Mesoamerica, highlighting it as extremely important for the conservation of the reptile fauna at local (southern Mexico) and regional levels (northern Mesoamerica).

8.
Angiol. (Barcelona) ; 73(1): 11-19, ene.-feb. 2021. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-202328

RESUMO

INTRODUCCIÓN: se estima que entre 18 y un 39 % de los pacientes con aneurismas del sector aortoilíaco sometidos a tratamiento endovascular presentan zonas no aptas para el sellado distal en arterias ilíacas comunes. Tradicionalmente, una de las opciones disponibles para abordar dicha situación consiste en realizar un sellado distal a nivel de las arterias ilíacas externas, ocluyendo las arterias hipogástricas. Sin embargo, esto conlleva la aparición de manifestaciones clínicas derivadas de la isquémica pélvica en el 28-55 % de los casos. La utilización de dispositivos ramificados ilíacos (DRI) permite mantener el flujo anterógrado a las arterias hipogástricas, lo que evita este tipo de complicaciones. El objetivo de nuestro estudio es analizar los resultados a medio plazo de la exclusión endovascular de aneurismas del sector aortoilíaco utilizando DRI. MÉTODOS: estudio descriptivo retrospectivo multicéntrico que incluye los DRI utilizados para el tratamiento endovascular de aneurismas de aorta con afectación del sector aortoilíaco entre enero de 2008 y julio de 2019. Se recogieron datos demográficos, anatómicos, intra- y perioperatorios y de seguimiento en tres centros. Las variables de interés analizadas fueron: éxito técnico, mortalidad perioperatoria, incidencia de isquemia pélvica, permeabilidad primaria de rama hipogástrica y rama ilíaca externa, reintervención relacionada con DRI y mortalidad relacionada con el aneurisma. RESULTADOS: se incluyeron 80 DRI implantados en 61 pacientes: 28 (35 %) Gore(R) Excluder(R) Iliac Branch Endoprosthesis y 52 (65 %) Cook(R) Zenith(R) Branch Endovascular Graft. Se implantaron DRI bilaterales en 18 casos (29,5 %). La tasa de éxito técnico fue del 95 % sin que existieran casos de muertes en el periodo perioperatorio. El seguimiento medio fue de 30,1 meses (± 26,3). Se presentaron seis casos de isquemia pélvica durante el seguimiento. La permeabilidad de la rama hipogástrica fue del 97,5 %, del 94,5 % y del 90,6 % a los 6, 12 y 24 meses, respectivamente. La permeabilidad de la rama ilíaca externa fue del 100 %, del 97,3 % y del 95,5 % a los 6, 12 y 24 meses, respectivamente. La tasa libre de reintervención secundaria al DRI fue del 100 %, del 96,8 % y del 94,7 % a los 6, 12 y 24 meses, respectivamente. Se produjo un caso de muerte relacionada con el aneurisma durante el seguimiento. CONCLUSIONES: en nuestra experiencia, los DRI presentan buenos resultados a medio plazo en la exclusión endovascular de aneurismas con afectación del sector aortoilíaco. Estos dispositivos permiten mantener la permeabilidad de las arterias hipogástricas, minimizando la incidencia de isquemia pélvica. A pesar de las escasas complicaciones tardías y la baja tasa de reintervenciones, es necesario realizar un seguimiento a largo plazo para mantener el éxito técnico


INTRODUCTION: it is estimated that between 18-39 % of patients with aorto-iliac aneurysms undergoing endovascular treatment have a no suitable zone for distal sealing in common iliac arteries. Traditionally, one of the options is to perform a distal seal at the external iliac arteries occluding the hypogastric arteries. However, this can lead to complications derived from pelvic ischemia in 28-55 % of cases. The use of iliac branched devices (IBD) allow to maintain the antegrade flow to the hypogastric arteries, avoiding these complications. The objective of our study is to analyze the medium-term results of endovascular exclusion of aorto-iliac aneurysms using IBD. METHODS: a descriptive multicenter retrospective study including the IBD for the endovascular treatment of aneurysms with involvement of the aorto-iliac sector was conducted between January 2008 and July 2019. Demographic, anatomical, intra-perioperative and follow-up data was collected at 3 centers. The variables of interest analyzed were: technical success, perioperative mortality, incidence of pelvic ischemia, primary patency of the hypogastric branch and external iliac branch, DRI-related reoperation, and aneurysm-related mortality. RESULTS: eighty IBDs were included from 61 patients: 28 (35 %) Gore(R) Excluder(R) Iliac Branch Endoprosthesis, and 52 (65 %) Cook(R) Zenith(R) Branch Endovascular Graft. Bilateral IBDs were implanted in 18 cases (29.5 %). The technical success was achieved in 95 % of cases, with no perioperative deaths. The mean follow-up was 30.1 (± 26.3) months. 6 patients presented pelvic ischemia during follow-up. The patency of the hypogastric side branch was 97.5 %, 94.5 %, and 90.6 %, at 6, 12, and 24 months, respectively. The patency of the external iliac side branch was 100 %, 97.3 %, and 95.5 %, at 6, 12, 24 months, respectively. Freedom from reintervention rate secondary to IBD was 100 %, 96.8 %, and 94.7 %, at 6, 12, and 24 months, respectively. There was 1 case of aneurysm-related death during follow-up. CONCLUSIONS: in our experience, IBDs show good medium-term results in endovascular treatment of aorto-iliac aneurysms. These devices allow to maintain the perfusion of the hypogastric arteries, minimizing the incidence of pelvic ischemia. Although the appearance of late complications and the need for reinterventions is low, a long-term follow-up should be carried out to maintain the success of the procedure


Assuntos
Humanos , Masculino , Feminino , Idoso , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma Ilíaco/cirurgia , Procedimentos Endovasculares/métodos , Prótese Vascular/normas , Estudos Retrospectivos , Desenho de Prótese , Resultado do Tratamento , Aneurisma da Aorta Abdominal/mortalidade , Aneurisma Ilíaco/mortalidade , Procedimentos Endovasculares/mortalidade , Estimativa de Kaplan-Meier , Seguimentos
9.
PLoS One ; 15(11): e0242020, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33170890

RESUMO

Tropical forest restoration initiatives are becoming more frequent worldwide in an effort to mitigate biodiversity loss and ecosystems degradation. However, there is little consensus on whether an active or a passive restoration strategy is more successful for recovering biodiversity because few studies make adequate comparisons. Furthermore, studies on animal responses to restoration are scarce compared to those on plants, and those that assess faunal recovery often focus on a single taxon, limiting the generalization of results. We assessed the success of active (native mixed-species plantations) and passive (natural regeneration) tropical cloud forest restoration strategies based on the responses of three animal taxa: amphibians, ants, and dung beetles. We compared community attributes of these three taxa in a 23-year-old active restoration forest, a 23-year-old passive restoration forest, a cattle pasture, and a mature forest, with emphasis on forest-specialist species. We also evaluated the relationship between faunal recovery and environmental variables. For all taxa, we found that recovery of species richness and composition were similar in active and passive restoration sites. However, recovery of forest specialists was enhanced through active restoration. For both forests under restoration, similarity in species composition of all faunal groups was 60-70% with respect to the reference ecosystem due to a replacement of generalist species by forest-specialist species. The recovery of faunal communities was mainly associated with canopy and leaf litter covers. We recommend implementing active restoration using mixed plantations of native tree species and, whenever possible, selecting sites close to mature forest to accelerate the recovery of tropical cloud forest biodiversity. As active restoration is more expensive than passive restoration, both strategies might be used in a complementary manner at the landscape level to compensate for high implementation costs.


Assuntos
Conservação dos Recursos Naturais/métodos , Recuperação e Remediação Ambiental/métodos , Clima Tropical , Anfíbios , Animais , Formigas , Biodiversidade , Besouros , Ecossistema , Florestas , México , Árvores/fisiologia
10.
J Therm Biol ; 89: 102565, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32364996

RESUMO

Most predictions of how populations and species of ectotherms will respond to global warming are based on estimates of the temperature at which organisms lose motor control (i.e., CTmax - the Critical Thermal Maximum). Here, we describe a non-lethal protocol and ethograms to estimate the relative tolerance of amphibians to increasing temperatures. These methods-suitable for field or laboratory conditions-are replicable, inexpensive and applicable to both post-metamorphic stages and organisms with direct development. We illustrate the use of this standardized protocol for four amphibians from a tropical cloud forest in Veracruz, Mexico with contrasting life histories: a lungless salamander (Aquiloeurycea cafetalera: Plethodontidae), a leaf-litter frog (Craugastor rhodopis: Craugastoridae), a semiaquatic frog (Lithobates berlandieri: Ranidae), and a tree frog (Rheohyla miotympanum: Hylidae). We identified four behavioral responses preceding CTmax for all amphibians included in this study: 1) Optimal Activity Range, 2) Supra-optimal Activity Range, 3) Heat Stress Range, and 4) Involuntary Movements Range. Additionally, we identified a fifth parameter associated with resilience to heat shock: 5) Recovery Stage after reaching CTmax. We conclude that the behavioral responses preceding the Critical Thermal Maximum are as informative as CTmax. Using behavioral responses to estimate thermal tolerance has the additional advantage of reducing the risk of injury or death of amphibians during physiological experiments.


Assuntos
Anfíbios/fisiologia , Comportamento Animal , Termotolerância , Anfíbios/crescimento & desenvolvimento , Animais , Temperatura Corporal , Mudança Climática , Etologia/instrumentação , Etologia/métodos , Movimento
11.
Rev. biol. trop ; 67(1): 196-205, Jan.-Mar. 2019. graf
Artigo em Espanhol | LILACS | ID: biblio-1041903

RESUMO

Resumen La composición de la dieta en anfibios puede ser influenciada por diversos factores que causan su variación intraespecífica, como pueden ser la distribución geográfica, ontogenia, estacionalidad, y el sexo de los organismos. El objetivo de este estudio fue analizar la composición de la dieta en adultos de la Craugastor rhodopis (rana hojarasquera común) en la región montañosa del centro de Veracruz, México. Un total de 77 individuos adultos fueron colectados durante la época de lluvias de 2012, de los cuales 66 tuvieron contenido estomacal. Se realizó un análisis de la variación intersexual en la diversidad de la dieta, y el volumen, número de presas, y número de categorías de presa consumidas. La dieta de C. rhodopis estuvo compuesta por 20 categorías, de las cuales predominó Orthoptera en cuanto a número, volumen, frecuencia de ocurrencia e importancia relativa. Los machos consumieron presas de menor tamaño en relación a las hembras. Aunque ambos sexos consumieron similar número de presas, se encontró un efecto significativo de la interacción del sexo y el tamaño de las ranas sobre esta variable de la dieta, en la cual las hembras pequeñas consumen más presas que las grandes, y los machos grandes consumen más presas que los pequeños. El alto consumo de ortópteros (al menos en cuanto a volumen) es un fenómeno común dentro de la familia Craugastoridae y posiblemente está relacionado con el éxito de algunas especies en los ecosistemas donde habitan. A pesar de que la composición de la dieta fue similar entre sexos en C. rhodopis, se sugiere que la competencia intersexual por los recursos tróficos es mínima, dadas las diferencias en el tamaño de presas consumidas por machos y hembras.(AU)


Abstract Dietary composition in amphibians may be influenced by several factors that cause their intraspecific variation, such as geographic distribution, ontogeny, seasonality, and sex of organisms. The objective of this study was to analyze the composition of the diet in adults of the Polymorphic Robber Frog Craugastor rhodopis in the mountainous region of central Veracruz, Mexico. A total of 77 adult individuals were collected during the rainy season of 2012, of which 66 had stomach contents. We performed an analysis of the intersexual variation in diet diversity, volume, number of prey, and number of prey categories consumed. The diet of C. rhodopis was composed by 20 categories. Orthoptera predominated in terms of number, volume, frequency of occurrence, and relative importance. Males consumed smaller prey items relative to females. Although both sexes consumed similar numbers of prey, we found a significant effect of interaction of sex and size of frogs on this variable, with small females consuming more prey than the large ones, whereas in males the opposite occurred. High consumption of orthopterans (at least in volume) is a common phenomenon within Craugastoridae and is possibly related to the success of some species in the ecosystems where they live. Although the composition of the diet was similar between sexes in C. rhodopis, we suggest that intersexual competition for trophic resources is minimal, given differences in prey size consumed by males and females.(AU)


Assuntos
Cadeia Alimentar , Composição de Alimentos , Anfíbios/metabolismo , Modelos Lineares , México
12.
Zootaxa ; 4277(4): 573-582, 2017 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-30308632

RESUMO

We describe a new plethodontid salamander species of the genus Isthmura, known only from one locality in the mountainous region of central Veracruz, Mexico. Like its congeners, Isthmura corrugata sp. nov. has a large and robust body, but it is easily distinguished from the other species in the genus by the absence of any spot or mark on the dorsum (except by dull reddish brown coloration on eyelids) and by extremely well-marked costal grooves separated by very pronounced costal folds. Based on an mtDNA phylogeny, the new species is most closely related to the geographically distant I. boneti and I. maxima but occurs very near I. naucampatepetl and I. gigantea on the eastern slope of Cofre de Perote, Veracruz. The region where I. corrugata occurs contains a high number of plethodontid salamander species and is threatened by human activity.


Assuntos
Florestas , Urodelos , Animais , DNA Mitocondrial , Atividades Humanas , Humanos , México , Filogenia
13.
PLoS One ; 10(3): e0121652, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25799369

RESUMO

Many regions around the world concentrate a large number of highly endangered species that have very restricted distributions. The mountainous region of central Veracruz, Mexico, is considered a priority area for amphibian conservation because of its high level of endemism and the number of threatened species. The original tropical montane cloud forest in the region has been dramatically reduced and fragmented and is now mainly confined to ravines and hillsides. We evaluated the current situation of amphibian diversity in the cloud forest fragments of this region by analyzing species richness and abundance, comparing assemblage structure and species composition, examining the distribution and abundance of threatened species, and identifying the local and landscape variables associated with the observed amphibian diversity. From June to October 2012 we sampled ten forest fragments, investing 944 person-hours of sampling effort. A total of 895 amphibians belonging to 16 species were recorded. Notable differences in species richness, abundance, and assemblage structure between forest fragments were observed. Species composition between pairs of fragments differed by an average of 53%, with the majority (58%) resulting from species replacement and the rest (42%) explained by differences in species richness. Half of the species detected are under threat of extinction according to the International Union for Conservation of Nature, and although their distribution and abundance varied markedly, there were also ubiquitous and abundant species, along with rare species of restricted distribution. The evident heterogeneity of the ten study sites indicates that to conserve amphibians in a mountainous region such as this one it is necessary to protect groups of fragments which represent the variability of the system. Both individually and together cloud forest fragments are very important to conservation because each remnant is inhabited by several threatened species, some of them at imminent risk of extinction.


Assuntos
Anfíbios , Biodiversidade , Espécies em Perigo de Extinção/estatística & dados numéricos , Clima Tropical , Anfíbios/classificação , Animais , Conservação dos Recursos Naturais , Florestas , México
14.
Epilepsy Behav ; 31: 267-75, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24262783

RESUMO

Attention deficit/hyperactivity disorder (ADHD) is encountered among patients with epilepsy at a significantly higher rate than in the general population. Mechanisms of epilepsy-ADHD comorbidity remain largely unknown. We investigated whether a model of chronic epilepsy in rats produces signs of ADHD, and thus, whether it can be used for studying mechanisms of this comorbidity. Epilepsy was induced in male Wistar rats via pilocarpine status epilepticus. Half of the animals exhibited chronic ADHD-like abnormalities, particularly increased impulsivity and diminished attention in the lateralized reaction-time task. These impairments correlated with the suppressed noradrenergic transmission in locus coeruleus outputs. The other half of animals exhibited depressive behavior in the forced swimming test congruently with the diminished serotonergic transmission in raphe nucleus outputs. Attention deficit/hyperactivity disorder and depressive behavior appeared mutually exclusive. Therefore, the pilocarpine model of epilepsy affords a system for reproducing and studying mechanisms of comorbidity between epilepsy and both ADHD and/or depression.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/complicações , Sintomas Comportamentais/etiologia , Epilepsia/complicações , Animais , Transtorno do Deficit de Atenção com Hiperatividade/induzido quimicamente , Transtorno do Deficit de Atenção com Hiperatividade/patologia , Encéfalo/metabolismo , Doença Crônica , Comportamento Compulsivo/induzido quimicamente , Convulsivantes/toxicidade , Modelos Animais de Doenças , Epilepsia/induzido quimicamente , Epilepsia/patologia , Lateralidade Funcional/efeitos dos fármacos , Resposta de Imobilidade Tônica/efeitos dos fármacos , Cloreto de Lítio/toxicidade , Masculino , Estimulação Luminosa , Pilocarpina/toxicidade , Ratos , Ratos Wistar , Tempo de Reação/efeitos dos fármacos , Natação/psicologia
15.
Ann Neurol ; 74(1): 11-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23907982

RESUMO

OBJECTIVE: Maternal immune activation (MIA) triggered by infections has been identified as a cause of autism in offspring. Considering the involvement of perturbations in innate immunity in epilepsy, we examined whether MIA represents a risk factor for epilepsy as well. The role of specific MIA components interleukin (IL)-6 and IL-1ß was also addressed. METHODS: MIA was induced in C57BL/6 mice by polyinosinic-polycytidylic acid (PIC) injected during embryonic days 12 to 16. Beginning from postnatal day 40, the propensity of the offspring to epilepsy was examined using hippocampal kindling; autismlike behavior was studied using the sociability test. The involvement of IL-6 and IL-1ß in PIC-induced effects was studied by the coadministration of the cytokine antibodies with PIC, and by delivering recombinant cytokines in lieu of PIC. RESULTS: The offspring of PIC-exposed mice exhibited increased hippocampal excitability, accelerated kindling rate, prolonged increase of seizure susceptibility after kindling, and diminished sociability. Epileptic impairments were abolished by antibodies to IL-6 or IL-1ß. Neither of the recombinant cytokines alone increased the propensity to seizures; however, when combined, they produced effects similar to those induced by PIC. PIC-induced behavioral deficits were abolished by IL-6 antibodies and were mimicked by recombinant IL-6; IL-1ß was not involved. INTERPRETATION: In addition to confirming the previously established critical role of IL-6 in the development of autismlike behavior following MIA, the present study shows that concurrent involvement of IL-6 and IL-1ß is required for priming the offspring for epilepsy. These data shed light on mechanisms of comorbidity between autism and epilepsy.


Assuntos
Epilepsia/etiologia , Hipocampo/patologia , Excitação Neurológica/patologia , Efeitos Tardios da Exposição Pré-Natal/imunologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Animais , Anticorpos/administração & dosagem , Temperatura Corporal/efeitos dos fármacos , Epilepsia/tratamento farmacológico , Feminino , Hipocampo/efeitos dos fármacos , Indutores de Interferon/toxicidade , Interleucina-1beta/sangue , Interleucina-1beta/imunologia , Interleucina-6/sangue , Interleucina-6/imunologia , Excitação Neurológica/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Poli I-C/toxicidade , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Comportamento Social
16.
Parasitology ; 140(14): 1799-810, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23981661

RESUMO

Culicoides vectors can transmit a diverse array of parasites and are globally distributed. We studied feeding preferences and seasonal variation of Culicoides (Diptera: Ceratopogonidae) vectors in an urban forest of Germany to determine whether humans living nearby are readily exposed to vector-borne parasites from wild animals. We used a fragment of the mtDNA COI gene to identify hosts from blood meals. We amplified a fragment of the mtDNA cyt b to detect haemosporidian infections in Culicoides abdomens and thoraxes. We detected a total of 22 Culicoides species. Fifty-eight blood meals (84%) were from humans, 10 from birds, and one from livestock. We found Culicoides kibunensis (considered ornithophilic) with 29 human blood meals. Host generalist Culicoides festivipennis and Culicoides obsoletus had 14 human blood meals. Culicoides clastrieri and Culicoides semimaculatus fed on birds; previously humans were their only known host. Six thoraxes and three abdomens were infected with either Haemoproteus pallidulus or Haemoproteus parabelopolskyi. There were changes in Culicoides community structure across months. Culicoides pictipennis was the dominant species during spring, C. kibunensis and C. clastrieri were dominant during summer, and C. obsoletus was dominant by early autumn. All dominant species were generalists feeding on birds, livestock and humans. Our results indicate that humans can serve as a blood source for dominant Culicoides species instead of the normal wild animal hosts in urban areas.


Assuntos
Doenças das Aves/parasitologia , Ceratopogonidae/fisiologia , Comportamento Alimentar/fisiologia , Haemosporida/isolamento & purificação , Insetos Vetores/fisiologia , Infecções Protozoárias em Animais/parasitologia , Animais , Doenças das Aves/epidemiologia , Aves , Ceratopogonidae/classificação , Cidades , Alemanha/epidemiologia , Humanos , Insetos Vetores/classificação , Infecções Protozoárias em Animais/epidemiologia , Estações do Ano , Árvores , Zoonoses
17.
J Neuroinflammation ; 10: 30, 2013 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-23442201

RESUMO

BACKGROUND: Inflammatory signaling elicited by prolonged seizures can be contributory to neuronal injury as well as adverse plasticity leading to the development of spontaneous recurrent seizures (epilepsy) and associated co-morbidities. In this study, developing rat pups were subjected to lithium-pilocarpine status epilepticus (SE) at 2 and 3 weeks of age to study the effect of anti-inflammatory drugs (AID) on SE-induced hippocampal injury and the development of spontaneous seizures. FINDINGS: We selected AIDs directed against interleukin-1 receptors (IL-1ra), a cyclooxygenase-2 (COX-2) inhibitor (CAY 10404), and an antagonist of microglia activation of caspase-1 (minocycline). Acute injury after SE was studied in the 2-week-old rats 24 h after SE. Development of recurrent spontaneous seizures was studied in 3-week-old rats subjected to SE 4 months after the initial insult.None of those AIDs were effective in attenuating CA1 injury in the 2-week-old pups or in limiting the development of spontaneous seizures in 3-week-old pups when administered individually. When empiric binary combinations of these drugs were tried, the combined targeting of IL-1r and COX-2 resulted in attenuation of acute CA1 injury, as determined 24 h after SE, in those animals. The same combination administered for 10 days following SE in 3-week-old rats, reduced the development of spontaneous recurrent seizures and limited the extent of mossy fiber sprouting. CONCLUSIONS: Deployment of an empirically designed 'drug cocktail' targeting multiple inflammatory signaling pathways for a limited duration after an initial insult like SE may provide a practical approach to neuroprotection and anti-epileptogenic therapy.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Anticonvulsivantes/administração & dosagem , Encéfalo/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Estado Epiléptico/prevenção & controle , Animais , Animais Recém-Nascidos , Encéfalo/patologia , Quimioterapia Combinada , Ratos , Ratos Wistar , Estado Epiléptico/patologia , Resultado do Tratamento
18.
Neurotherapeutics ; 9(2): 245-61, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22467296

RESUMO

When mimicking epileptic processes in a laboratory setting, it is important to understand the differences between experimental models of seizures and epilepsy. Because human epilepsy is defined by the appearance of multiple spontaneous recurrent seizures, the induction of a single acute seizure without recurrence does not constitute an adequate epilepsy model. Animal models of epilepsy might be useful for various tasks. They allow for the investigation of pathophysiological mechanisms of the disease, the evaluation, or the development of new antiepileptic treatments, and the study of the consequences of recurrent seizures and neurological and psychiatric comorbidities. Although clinical relevance is always an issue, the development of models of pediatric epilepsies is particularly challenging due to the existence of several key differences in the dynamics of human and rodent brain maturation. Another important consideration in modeling pediatric epilepsy is that "children are not little adults," and therefore a mere application of models of adult epilepsies to the immature specimens is irrelevant. Herein, we review the models of pediatric epilepsy. First, we illustrate the differences between models of pediatric epilepsy and models of the adulthood consequences of a precipitating insult in early life. Next, we focus on new animal models of specific forms of epilepsies that occur in the developing brain. We conclude by emphasizing the deficiencies in the existing animal models and the need for several new models.


Assuntos
Encéfalo/patologia , Modelos Animais de Doenças , Epilepsia/patologia , Fatores Etários , Animais , Encéfalo/fisiologia , Criança , Epilepsia/genética , Epilepsia/fisiopatologia , Humanos
19.
PLoS One ; 7(4): e34023, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22485155

RESUMO

Worldwide, one in every three species of amphibian is endangered, 39 species have gone extinct in the last 500 years and another 130 species are suspected to have gone extinct in recent decades. Of the amphibians, salamanders have the highest portion of their species in one of the risk categories, even higher than the frogs. To date there have been few studies that have used recent field data to examine the status of populations of endangered salamanders. In this study we evaluate the current situation of two tiny salamanders, Parvimolge townsendi and Thorius pennatulus, both of which are distributed at intermediate elevations in the mountains of the northern Neotropics and are considered to be critically endangered; the first has been proposed as possibly extinct. By carrying out exhaustive surveys in both historical and potentially suitable sites for these two species, we evaluated their abundance and the characteristics of their habitats, and we estimated their potential geographic distribution. We visited 22 sites, investing 672 person-hours of sampling effort in the surveys, and found 201 P. townsendi salamanders in 11 sites and only 13 T. pennatulus salamanders in 5 sites. Both species were preferentially found in cloud forest fragments that were well conserved or only moderately transformed, and some of the salamanders were found in shade coffee plantations. The potential distribution area of both species is markedly fragmented and we estimate that it has decreased by more than 48%. The results of this study highlight the importance of carrying out exhaustive, systematic field surveys to obtain accurate information about the current situation of critically endangered species, and help us better understand the crisis that amphibians are facing worldwide.


Assuntos
Espécies em Perigo de Extinção , Salamandridae , Animais , Ecossistema , México , Filogeografia , Clima Tropical
20.
Neurotherapeutics ; 9(2): 477-85, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22427156

RESUMO

Depression represents a common comorbidity of epilepsy and is frequently resistant to selective serotonin reuptake inhibitors (SSRI). We tested the hypothesis that the SSRI resistance in epilepsy associated depression may be a result of a pathologically enhanced interleukin-1ß (IL1-ß) signaling, and consequently that the blockade of IL1-ß may restore the effectiveness of SSRI. Epilepsy and concurrent depression-like impairments were induced in Wistar rats by pilocarpine status epilepticus (SE). The effects of the 2-week long treatment with fluoxetine, interleukin-1 receptor antagonist (IL-1ra), and their combination were examined using behavioral, biochemical, neuroendocrine, and autoradiographic assays. In post-SE rats, depression-like impairments included behavioral deficits indicative of hopelessness and anhedonia; the hyperactivity of the hypothalamo-pituitary-adrenocortical axis; the diminished serotonin output from raphe nucleus; and the upregulation of presynaptic serotonin 1-A (5-HT1A) receptors. Fluoxetine monotherapy exerted no antidepressant effects, whereas the treatment with IL-1ra led to the complete reversal of anhedonia and to a partial improvement of all other depressive impairments. Combined administration of fluoxetine and IL-1ra completely abolished all hallmarks of epilepsy-associated depressive abnormalities, with the exception of the hyperactivity of the hypothalamo-pituitary-adrenocortical axis, the latter remaining only partially improved. We propose that in certain forms of depression, including but not limited to depression associated with epilepsy, the resistance to SSRI may be driven by the pathologically enhanced interleukin-1ß signaling and by the subsequent upregulation of presynaptic 5-HT1A receptors. In such forms of depression, the use of interleukin-1ß blockers in conjunction with SSRI may represent an effective therapeutic approach.


Assuntos
Antidepressivos de Segunda Geração/uso terapêutico , Depressão/tratamento farmacológico , Modelos Animais de Doenças , Epilepsia/tratamento farmacológico , Fluoxetina/uso terapêutico , Interleucina-1beta/uso terapêutico , Animais , Depressão/etiologia , Depressão/metabolismo , Resistência a Medicamentos/fisiologia , Epilepsia/complicações , Epilepsia/metabolismo , Interleucina-1beta/metabolismo , Masculino , Ratos , Ratos Wistar
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