Assessing Ecogeographic Rules in Two Sigmodontine Rodents along an Elevational Gradient in Central Chile.

Bergmann's and Allen's rules are two classic ecogeographic rules concerning the physiological mechanisms employed by endotherm vertebrates for heat conservation in cold environments, which correlate with adaptive morphological changes. Thus, larger body sizes (Bergmann's rule) and shorter appendages and limbs (Allen's rule) are expected in mammals inhabiting cold environments (higher latitudes). Both rules may also apply to elevational gradients, due to the decrease in external temperature as elevation increases. In this study, we evaluated whether these patterns were true in two coexisting sigmodontine rodents across an elevational gradient in central Chile. We analyzed whether the size of the skull, body, and appendages of Abrothrix olivacea (n = 70) and Phyllotis darwini (n = 58) correlated with elevation, as predicted by these rules in a range between 154 and 2560 m. Our data revealed weak support for the Bergmann and Allen predictions. Moreover, we observed opposite patterns when expectations of Bergmann's rules were evaluated, whereas Allen's rule just fitted for ear size in both rodent species. Our results suggest that morphological changes (cranial, body, and appendage sizes) may play a minor role in the thermoregulation of these two species at high elevations, although behavioral strategies could be more critical. Other ecological and environmental variables could explain the morphological trends observed in our study. These hypotheses should be assessed in future studies to consider the relative contribution of morphology, behavior, and physiological mechanisms to the thermal adaptation of these two rodent species at high elevations.

Differential recovery ability from infections by two blood parasite genera in males of a Mediterranean lacertid lizard after an experimental translocation.

Different blood parasites can co-infect natural populations of lizards. However, our knowledge of the host's ability to recover from them (i.e., significantly reduce parasitemia levels) is scarce. This has interest from an ecological immunology perspective. Herein, we investigate the host recovery ability in males of the lizard Psammodromus algirus infected by parasite genera Schellackia and Karyolysus. The role of lizard hosts is dissimilar in the life cycle of these two parasites, and thus different immune control of the infections is expected by the vertebrate host. As Schellackia performs both sexual and asexual reproduction cycles in lizards, we expect a better immune control by its vertebrate hosts. On the contrary, Karyolysus performs sexual reproductive cycles in vectors, hence we expect lower immune control by the lizards. We carried out a reciprocal translocation experiment during the lizards' mating season to evaluate both parasitemia and leukocyte profiles in male lizards, being one of the sampling plots close to a road with moderate traffic. These circumstances provide a combination of extrinsic (environmental stress) and intrinsic factors (reproductive vs. immune trade-offs) that may influence host's recovery ability. We recaptured 33% of the lizards, with a similar proportion in control and translocated groups. Karyolysus infected 92.3% and Schellackia 38.5% of these lizards. Hosts demonstrated ability to significantly reduce parasitemia of Schellackia but not of Karyolysus. This suggests, in line with our predictions, a differential immune relationship of lizards with these parasites, at time that supports that parasites with different phylogenetic origins should be analyzed separately in investigations of their effects on hosts. Furthermore, lizards close to the road underwent a stronger upregulation of lymphocytes and monocytes when translocated far from the road, suggesting a putative greater exposure to pathogens in the latter area.

First helminthological data on the Iberian adder, Vipera seoanei.

The helminth fauna present in the gut contents of Iberian adders, Vipera seoanei (Squamata: Viperidae), were characterised and analysed in respect to biological and eco-geographic factors that may affect the occurrence and diversity of helminths in this species. A total of 317 samples of preserved stomachs and intestines, covering the distributional range of V. seoanei, were examined. Similar to other Vipera species from the Iberian Peninsula, the helminth fauna was also impoverished in V. seoanei, but unlike other Vipera species from Central and East Europe, helminths were mostly found in adult vipers, and occurred in vipers located at the periphery of the species range, characterised by low elevation, high temperature and precipitation levels, and abundant pastures.

The importance of the Andes in the evolutionary radiation of Sigmodontinae (Rodentia, Cricetidae), the most diverse group of mammals in the Neotropics.

The Andean mountains stand out for their striking species richness and endemicity that characterize many emblematic Neotropical clades distributed in or around these mountains. The radiation of the Sigmodontinae subfamily, the most diversified mammalian group in the Neotropics, has been historically related to Andean orogenesis. We aim to evaluate this interplay between geological processes and biological responses through the diversification dynamics, the biogeographical history, and the range evolution of the subfamily. For these, we built the most comprehensive phylogeny and gathered 14,836 occurrences for the subfamily. We identified one shift in the speciation rate in the genus Akodon, which suffered their Andean radiation after the arrival of non-Andean ancestors. Our biogeographic analyses show multiple dispersal paths throughout the evolution that allowed this subfamily to colonize all Neotropics. The Northern Andes and Central-Southern Andes were the most important sources of diversity. In addition, the Central-Southern Andes were the most relevant sink, receiving the highest number of lineages. The Andean region exhibited higher speciation and turnover rates than non-Andean regions. Thus, our results support the crucial role of the Andean Mountains in the Sigmodontinae radiation, acting as a "macroevolutionary cradle" and "species attractor" for several sigmodontine lineages at different times, and as a "species pump" becoming the biogeographic source of multiple widely distributed neotropical lineages. Then, complex macroevolutionary dynamics would explain these rodents' high extant Andean diversity and their wide distribution in the Neotropics.

Mechanotransduction in tumor dynamics modeling.

Mechanotherapy is a groundbreaking approach to impact carcinogenesis. Cells sense and respond to mechanical stimuli, translating them into biochemical signals in a process known as mechanotransduction. The impact of stress on tumor growth has been studied in the last three decades, and many papers highlight the role of mechanics as a critical self-inducer of tumor fate at the in vitro and in vivo biological levels. Meanwhile, mathematical models attempt to determine laws to reproduce tumor dynamics. This review discusses biological mechanotransduction mechanisms and mathematical-biomechanical models together. The aim is to provide a common framework for the different approaches that have emerged in the literature from the perspective of tumor avascularity and to provide insight into emerging mechanotherapies that have attracted interest in recent years.

The management of endoscopic retrograde cholangio- pancreatography-related infections risk: results of an italian survey at regional level.

Background and aim: Among the Endoscopic retrograde cholangiopancreatography (ERCP) adverse events, an increasingly arising problem is the transmission of Multi Drug Resistant (MDR) Bacteria through duodenoscopes. The aim of this survey was to evaluate the current clinical practice of management of ERCP associated infections in Emilia-Romagna, Italy. Methods: An online survey was developed including 12 questions on management of ERCP associated infections risk. The survey was proposed to all 12 endoscopy centers in Emilia Romagna that perform at least > 200 ERCPs per year. Results: 11 centers completed the survey (92%). Among all risk factors of ERCP infections, hospitalization in intensive care units, immunosuppressant therapies, and previous MDR infections have achieved a 80 % minimum of concurrence by our respondents. The majority of them did not have a formalized document in their hospital describing categories and risk factors helpful in the detection of patients undergoing ERCP with an high-level infective risk (9/11, 82%). Most centers (8/11, 72%) do not perform screening in patients at risk of ERCP infections. Post procedural monitoring is performed by 6 of 11 centers (55%). Conclusion: Our survey showed that, at least at regional level, there is a lack of procedures and protocols related to the management of patients at risk of ERCP infections.

Ecological and evolutionary trends of body size in Pristimantis frogs, the world's most diverse vertebrate genus.

Body size is a key organismal trait. However, the environmental and evolutionary factors that drive body size patterns at the interspecific level remain unclear. Here, we explored these relationships between phenotype-environment using neotropical frogs of Pristimantis, the world's most diverse vertebrate genus. We analyzed: (a) whether this group follows the Rensch's rule, a trend of sexual size dimorphism (SSD) to increase with size when males are the larger sex; (b) whether environmental constraints have influenced body size variation; and (c) how the rates of body size evolution have varied over time. Analyses were based on two information sources, the first one including body sizes of ~ 85% (495 species) of known species in the genus, and a second one incorporating molecular phylogenetic information for 257 species. Our results showed that all Pristimantis species exhibited marked SSD but did not follow Rensch's rule. We found that the models that best explained body size in males, females, and SSD contained environmental variations in temperature, precipitation, and elevation as predictors. In turn, body size has evolved toward an optimum, with a decelerating rate of evolution differentiated between the large Pristimantis clades.

Fecal glucocorticoid metabolites and ectoparasites as biomarkers of heat stress close to roads in a Mediterranean lizard.

Differences between air and ground temperatures are expected to narrow with the advance of the season in temperate regions (aka seasonal restriction in the availability of thermal microhabitats), which may activate behavioral and physiological responses of ectotherm species adapted to temperate climates. However, according to cost-benefit models of ectotherm thermoregulation, we hypothesize that these responses may also carry some costs. We quantified seasonal shifts in thermoregulatory precision, concentration of fecal glucocorticoid metabolites, and load of ectoparasites in a Mediterranean lizard, Psammodromus algirus. We also tested whether the proximity to a road, a putative source of chronic stress, can facilitate the glucocorticoid-mediated response of lizards to heat stress. As expected, differences between body and environmental temperatures narrowed during the reproductive season and lizards responded by increasing their thermoregulatory precision and the secretion of glucocorticoids, as indicated by metabolites in feces. Interestingly, lizards tended to have higher glucocorticoid concentration when captured far from the road. This might reflect either a putative impairment of the glucocorticoid-mediated response of the lizards to heat stress close to the road or the plastic capability of P. algirus to acclimate to sources of moderate chronic stress. In the latter direction, the increase of both glucocorticoid metabolites and thermoregulatory precision supported that this Mediterranean species responds to environmental thermal restrictions with adaptive behavioral and physiological mechanisms. However, this was also associated with an increase in its susceptibility to ectoparasites, which represents an added cost to the current cost-benefit models of ectotherm thermoregulation.

Evaluación de satisfacción en la implementación de un nuevo sistema de telemedicina en el Servicio de Otorrinolaringología del Complejo Asistencial Dr. Sótero del Río (CASR) durante la pandemia de COVID-19

Resumen Introducción: Debido a la pandemia por SARS-CoV-2, las consultas presenciales y cirugías electivas fueron suspendidas o disminuidas para evitar la propagación viral hacia pacientes y personal de salud. En nuestro país se ha implementado la telemedicina como canal alternativo de atención. Debido a su reciente implementación en nuestra especialidad a nivel nacional, es importante conocer la percepción del paciente y proveedor sobre ella, con el fin de evaluar su factibilidad como nueva modalidad de atención en el futuro. Objetivo: Evaluar la satisfacción del paciente y del proveedor sobre el uso de telemedicina en Otorrinolaringología en nuestro hospital. Material y Método: Estudio prospectivo observacional. Se adaptaron dos instrumentos de evaluación de satisfacción reportados en la literatura, para el paciente y proveedor de salud. Las encuestas fueron administradas luego de la consulta de telemedicina a través de correo electrónico para el paciente, y como parte de la plataforma de telemedicina para el proveedor y respondidas en forma voluntaria. Las respuestas fueron analizadas utilizando medidas de frecuencia (porcentajes). Resultados: Se recopilaron 51 encuestas de pacientes y 69 de proveedores. En los pacientes, en un 98% la telemedicina facilitó el acceso a atención, siendo del mismo nivel que una presencial (91%). Un 98% volvería a usarla y la recomendaría a familiares o amigos. En los proveedores, el 98% estuvo satisfecho con la teleconsulta y 89% con la plataforma. Conclusión: La atención por telemedicina es satisfactoria para usuario y proveedor en nuestro hospital. Esta es una herramienta valiosa para complementar la atención clínica otorrinolaringológica.

Abstract Introduction: Due to the SARS-CoV-2 pandemic, clinical consults and elective surgeries were suspended or decreased to avoid spreading the disease to patients and health personnel. In our country telemedicine has been implemented as an alternate way to obtain medical attention. Given that this attention paradigm has only been recently implemented in our specialty at the national level, it is important to know the perception of the patient and health care provider in order to evaluate its feasibility as a new modality of care in the future. Aim: To assess the patients and healthcare providers satisfaction regarding the use of telemedicine in the Otorhinolaryngology Department. Material and Method: Prospective observational study. Two satisfaction surveys previously reported in the literature were adapted for the patient and health provider. The surveys were sent after each telemedicine consultation via email to the patient, and as part of the telemedicine platform for the provider and answered voluntarily. The responses were analyzed using proportions. Results: answered surveys were obtained from 51 patients and 69 healthcare providers. In 98% of patient's telemedicine facilitated access to care, which was found to be as good as a clinical consult in 91% of the telehealth visits. 98% would use it again and recommend it to family or friends. In 98% of providers were satisfied with the teleconsultation and 89% with the platform. Conclusion: teleconsultation is satisfactory for both patients and providers in our hospital. This new attention modality is a valuable tool to complement the standard otolaryngologist clinical assessment.

Plasticity of haemoglobin concentration and thermoregulation in a mountain lizard.

The plastic capability of species to cope with the new conditions created by climate change is poorly understood. This is particularly relevant for organisms restricted to high elevations because they are adapted to cold temperatures and low oxygen availability. Therefore, evaluating trait plasticity of mountain specialists is fundamental to understand their vulnerability to environmental change. We transplanted mountain lizards, Iberolacerta cyreni, 800 m downhill to evaluate the plastic response in body condition, thermoregulation traits, haemoglobin level, and haemoparasite load. Initial measurements of body mass, total haemoglobin concentration ([Hb]), hematic parasite intensities, dorsal luminance, and thermoregulatory behaviour were resampled after two and four weeks of acclimation. We also tested whether an anti-parasitic drug reduced haemoparasite intensity. After only two weeks of acclimation to a lower elevation, lizards decreased 42% in [Hb], had 17% less parasite intensities, increased body condition by 25%, and raised by ~3% their mean preferred temperatures and their voluntary thermal maximum. The anti-parasitic treatment had no significant effect on the intensity of hematic parasites, but our results suggest that negative effects of haemoparasites on [Hb] are relaxed at lower elevation. The rapid plastic changes observed in thermal preferences, body condition, [Hb], and parasite intensity of I. cyreni demonstrate a potential plastic response of a mountain specialist. This may be adaptive under the climatic extremes typical of mountain habitats. However, there is uncertainty in whether the observed plasticity can also help overcome long term environmental changes.

Geographic patterns of stress in insular lizards reveal anthropogenic and climatic signatures.

Anthropization of insular ecosystems may have negative impacts on native populations of lizards, which provide core ecosystem services on islands. We aimed to identify environmental factors to explain the interlocal variation in faecal glucocorticoids, parasite intensity, and body condition in populations of insular lizards. A cross-sectional design during the summer of 2017 and 2018 was used to sample 611 adult lizards, Gallotia galloti. Interlocal variation of three stress indicators was analysed in response to environmental variables across a wide environmental gradient in Tenerife (Canary Islands): (i) concentration of faecal glucocorticoids, (ii) intensities of infection by hematic parasites, and (iii) body condition. The data, with low spatial autocorrelation, were analysed using multimodel inference and model cross-validation. Bioclimatic variables associated with the extreme hot and dry climate of summer were the most informative predictors. Interlocal variation in faecal corticosterone in males was best fitted to a model that included the maximum temperature of the warmest month, although the best predictor was habitat anthropization. The thermal annual range, associated with extreme thermal events, was positively related to faecal corticosterone in females. Extreme hot temperatures were positively related to the median parasite intensities in both sexes, while the highest mean intensities of infection were found in females from the most xeric coastal localities. None of the predictors tested, including faecal glucocorticoids, explained individual or interlocal variation in body condition. Effects of human pressure and climate change on insular populations of lizards can be additive. However, the uncoupled relationship found between body condition and the faecal glucocorticoid content suggests that current negative effects may be aggravated during drought periods in summer. Given the impact of climate change on islands, our results may be of application to other archipelagos, where lizards also play key ecological roles.

Two new species of Pristimantis (Anura: Craugastoridae) with notes on the distribution of the genus in northeastern Colombia.

We describe two new species of the genus Pristimantis from the western margin of the Eastern Cordillera of Colombia. The species have a sympatric distribution and are found in the humid tropical forests of the lower part of the Tamá National Natural Park (PNN Tamá) and its buffer zone. The new species were described from morphological comparisons and phylogenetic reconstruction from the sequencing of three mitochondrial and two nuclear genes. With these two new species, the number of Pristimantis species known in the department of Norte de Santander has increased to 10. In addition, we included new sequences for the species P. anolirex, P. nicefori, P. mondolfii, and P. yukpa. Our explorations in the last decade indicate that there are probably between five and 10 species that have not been described in the northeastern part of Colombia, especially in areas where the armed conflict has predominated in the last five decades.

Enfrentamiento de pacientes Testigo de Jehová en cirugía otorrinolaringológica: a propósito de un caso de resección de tumor rinosinusal / Jehovah's Witnesses patients in otorhinolaryngological surgery: a case regarding a sinonasal tumor resection

Las cirugías de cabeza y cuello presentan un alto riesgo de sangrado que puede significar el uso de transfusiones sanguíneas. Existen casos en las que éstas son rechazadas, como sucede con los Testigos de Jehová. Se expone el caso de una paciente Testigo de Jehová con un tumor rinosinusal con alto riesgo de sangrado que consultó por epistaxis recurrente. Se evidencia un tumor ocluyendo la fosa nasal derecha de aspecto vascular a la rinoscopía y la tomografía computarizada. Múltiples aferencias de la arteria esfenopalatina y etmoidales se observaron en una angiografía cerebral. Previo a la resección, se embolizó la arteria maxilar. Durante la cirugía, se contó con un sistema de recuperación de sangre autóloga, hemodilución e infusión de ácido tranexámico. Se ligó la arteria etmoidal anterior derecha vía externa con apoyo endoscópico y luego se resecó el tumor vía endoscópica. La biopsia reveló un carcinoma sinonasal escamoso. Existen alternativas terapéuticas en pacientes que rechacen el uso de hemoderivados. Destacan medidas preoperatorias como la embolización endovascular, intraoperatorias como el uso de agentes hemostáticos, técnicas quirúrgicas y anestésicas. Es importante analizar todas las opciones disponibles de forma multidisciplinara y junto con el paciente, para determinar la conducta más adecuada a seguir.

Head and neck surgeries have a high risk of bleeding, and therefore could require the use of blood transfusions. There are cases for which blood transfusions are not an acceptable option, as is the case for Jehovah's Witnesses. We present the case of a Jehovah's Witness with a sinonasal tumor with a high risk of bleeding, who presented with recurrent epistaxis. Rhinoscopy and computed tomography revealed a vascular-like tumor occluding the right nasal cavity. Cerebral angiography showed afferents of the sphenopalatine and ethmoidal arteries leading to the tumor. Prior to the resection, the maxillary artery was embolized. During surgery, we relied on an autologous blood recovery system, hemodilution and tranexamic acid. Right anterior ethmoidal artery ligation was performed by an endoscopic assisted external approach. The tumor was resected endoscopically The biopsy revealed a squamous sinonasal carcinoma. There are therapeutic alternatives for patients who cannot receive blood products. There are preoperative measures such as endovascular embolization, intraoperative measures such as the use of hemostatic agents and specific surgical or anesthetic techniques. It's important to analyze all of the available options in a multidisciplinary team approach, and to take into consideration the patient's preferences, in order to determine the best surgical conduct.

Increased frequency of interleukin-4 and reduced frequency of interferon-γ and IL-17-producing CD4+ and CD8+ cells in scleromyxedema.

BACKGROUND: Little is known about the pathogenesis of scleromyxedema, a life-threatening fibromucinosis disease with immunological dysregulation. OBJECTIVES: To investigate on T-cell phenotype, function and cytokine biology in search of new insights supporting the immunopathogenesis of the disease. METHODS: We analysed the frequency of circulating lymphocyte subsets, the T-cell maturation stage, the generation of antigen-specific T-cell lines and T-cell cytokine secretion. RESULTS: The analysis of T-cell maturation stage and the TCR spectratyping findings revealed that scleromyxedema patients showed clear immunological signs of long-lasting immune system activation and stimulation leading to a skewed T-cell repertoire. Moreover, these analyses showed that both CD4+ and CD8+ T cells from scleromyxedema patients have a profound deficiency (even after stimulation) relatively to the production of IFN-γ and IL17 with respect to healthy donor control cells, while they are massively skewed towards IL4 secretion after stimulation. CONCLUSIONS: Our data indicate that a chronic Th2-skewed T-cell response against an unknown target antigen leading to abnormally high IL4 secretion, a pro-fibrotic cytokine, is a main immunological hallmark of scleromyxedema patients. These results, never reported before, may have a translational therapeutic value due to the availability of anti-IL4 agents such as dupilumab.

To cool or not to cool? Intestinal coccidians disrupt the behavioral hypothermia of lizards in response to tick infestation.

It is generally accepted that parasites exert negative effects on their hosts and that natural selection favors specific host responses that mitigate this impact. It is also known that some components of the host immune system often co-evolve with parasite antigens resulting in a host-parasite arms race. In addition to immunological components of the anti-parasitic response, host behavioral responses are also important in this arms race and natural selection may favor avoidance strategies that preclude contact with parasites, or shifts in the host's thermoregulatory strategy to combat active infections (e.g., behavioral fever). Ticks are widespread parasites with direct and indirect costs on their vertebrate hosts. Their saliva provokes hemolysis in the blood of their hosts and can transmit a plethora of tick-borne pathogens. We enquired whether tick infestation by Ixodes pacificus can provoke a thermoregulatory response in Sceloporus occidentalis. For this, we compared the thermoregulatory behavior of tick-infested lizards against tick-infested lizards co-infected with two different species of coccidians (Lankesterella occidentalis and Acroeimeria sceloporis). After this, lizards were kept in individual terraria with a basking spot and fed ad libitum. We found that tick-infested lizards sought cooler temperatures in proportion to their tick load, and this response was independent of the co-infection status by L. occidentalis. This was consistent in April and June (when tick loads were significantly lower) and suggests a conservative strategy to save energy which might have been selected to overcome tick infestations during phenological peaks of this parasite. However, this behavior was not observed in lizards co-infected with A. sceloporis, suggesting that co-infection with this intestinal parasite prompt lizards to be active. Cost of tick infestation was confirmed because housed lizards lost weight at a constant ratio to initial tick load, independently of other infections. The broader implications of these findings are discussed in the context of climate change.

A 19 Year Analysis of Small Mammals Associated with Human Hantavirus Cases in Chile.

Small mammals present in areas where hantavirus cardiopulmonary syndrome (HCPS) cases had occurred in central and southern Chile were captured and analyzed to evaluate the abundance of rodents and seroprevalence rates of antibodies to Andes orthohantavirus (ANDV). Sampling areas ranged from the Coquimbo to Aysén regions (30-45° S approx.) regions. Ninety-two sites in peridomestic and countryside areas were evaluated in 19 years of sampling. An antibody against ANDV was detected by strip immunoassay in 58 of 1847 specimens captured using Sherman traps. Of the eleven species of rodents sampled, Abrothrix olivacea, Oligoryzomys longicaudatus and Abrothrix hirta were the most frequently trapped. O. longicaudatus had the highest seropositivity rate, and by logistic regression analysis, O. longicaudatus of at least 60 g had 80% or higher probability to be seropositive. Sex, age and wounds were significantly related to seropositivity only for O. longicaudatus. Across administrative regions, the highest seropositivity was found in the El Maule region (34.8-36.2° S), and the highest number of HCPS cases was registered in the Aysén region. Our results highlight the importance of long term and geographically extended studies, particularly for highly fluctuating pathogens and their reservoirs, to understand the implications of the dynamics and transmission of zoonotic diseases in human populations.

Experimental data on the relationship between dyes sensitizers and wavelength during the photocatalytic degradation of diclofenac.

Sensitizers are being used to improve the photocatalytic activity of semiconductors in the visible light region of the solar spectrum. Different types of dyes are reported as sensitizer agents, such as ruthenium complex molecules, porphyrins and Pt complexes, which are critically assessed because they are hazardous substance. Therefore, it is necessary to replace these compounds with safer sensitizer like organic dyes. This work evaluated the photocatalytic degradation of diclofenac using two different types of organic dyes (Perinaphtenone and Eosin-Y) as sensitizer agents. The catalyst concentration [0.15; 0.35 g/l], source of light (UVA - Vis) and type of dye were evaluated. The data obtained can be useful to classify organic dyes that could be employees as sensitizers and which is the wavelength more adequate to use as an energy source. The Kapp for the reaction has values between 1*10-3 to 5*10-3 min-1 for UVA, 3*10-4 to 3*10-3 min-1 for Vis and 2*10-3 to 6*10-3 min-1 for UV-Vis.

Genetic Diversity, Population Structure, and Migration Scenarios of the Marsupial "Monito del Monte" in South-Central Chile.

In this study, we quantified the 3 pivotal genetic processes (i.e., genetic diversity, spatial genetic structuring, and migration) necessary for a better biological understanding and management of the singular "living-fossil" and near-threatened mouse opossum marsupial Dromiciops gliroides, the "Monito del Monte," in south-central Chile. We used 11 microsatellite loci to genotype 47 individuals distributed on the mainland and northern Chiloé Island. Allelic richness, observed and expected heterozygosity, inbreeding coefficient, and levels of genetic differentiation were estimated. The genetic structure was assessed based on Bayesian clustering methods. In addition, potential migration scenarios were evaluated based on a coalescent theory framework and Bayesian approach to parameter estimations. Microsatellites revealed moderate to high levels of genetic diversity across sampled localities. Moreover, such molecular markers suggested that at least 2 consistent genetic clusters could be identified along the D. gliroides distribution ("Northern" and "Southern" cluster). However, general levels of genetic differentiation observed among localities and between the 2 genetic clusters were relatively low. Migration analyses showed that the most likely routes of migration of D. gliroides occurred 1) from the Southern cluster to the Northern cluster and 2) from the Mainland to Chiloé Island. Our results could represent critical information for future conservation programs and for a recent proposal about the taxonomic status of this unique mouse opossum marsupial.

Genetic variability and structure of the Olive Field Mouse: a sigmodontine rodent in a biodiversity hotspot of southern Chile.

The temperate rainforests of southern Chile, a recognized biodiversity hotspot, were significantly affected by Pleistocene glacial cycles in their southern portion and have been severely disrupted mainly due to recent human activities. Additionally, the landscape is characterized by a series of potential barriers to gene flow, such as the Chacao Channel, Cordillera de Piuche in Chiloé and both the Ancud and the Corcovado gulfs. We used mitochondrial DNA sequences and microsatellite data across several populations to evaluate the genetic variability and structure of the sigmodontine rodent Abrothrix olivacea brachiotis, one of the most common species of small mammals and an inhabitant of these biodiverse forests. Sequencing data showed that along with the recovery of high haplotype variation for this species, there was a low nucleotide diversity between haplotypes, showing no genetic differences between the Chiloé Island and continental populations in southern Chile or through any other geographic barrier in the study area. However, microsatellite data exhibited some level of population structuring. The most evident clusterings were those of the Chiloé Island and that of North Patagonia. These findings are corroborated by a barrier analysis that showed a genetic barrier in the latter areas, whereas the Chacao Channel was not a significant barrier for this rodent. Overall, the genetic variability and structure of A. o. brachiotis was concordant with historical factors, such as the Last Glacial Maximum and the presence of geographic elements that isolate populations.

Experiencia clínica y manejo de los abscesos periamigdalinos en el Complejo Asistencial Dr. Sótero del Río / Clinical experience and management of peritonsillar abscesses at the Dr. Sótero del Río Health Center

RESUMEN Introducción: El absceso periamigdalino es una causa importante de consulta de urgencia en los servicios de otorrinolaringología. Su manejo incluye tratamientos antibióticos y drenaje del absceso. Objetivo: Describir y analizar las características clínicas, epidemiológicas y manejo de los abscesos periamigdalinos en el Complejo Asistencial Dr. Sótero del Río. Material y método: Estudio retrospectivo, descriptivo, incluyendo a todos los pacientes con un absceso periamigdalino entre los años 2013 y 2016. Se analizaron variables epidemiológicas, clínicas, uso de antibióticos, drenajes, y persistencia del cuadro. Resultados: La serie está constituida por 122 pacientes, con una edad promedio de 29 años. Diez y nueve coma seis por ciento corresponde a pacientes pediátricos. La clínica se caracterizó principalmente por odinofagia (62,7%), voz engolada (32%), fiebre (27%) y trismus (27%). Al examen físico, se observó abombamiento del pilar (67,2%), desplazamiento de la úvula (41,8%), trismus (26,2%), y placas blanquecinas sobre la amígdala (18,9%). Este último hallazgo fue más frecuente en la población pediátrica. El 46,2% de los pacientes recibió algún tratamiento antibiótico antes de consultar en el servicio de urgencia, y el 35,7% de los pacientes recibieron corticoides durante la consulta al servicio de urgencia. En la gran mayoría (92%), se realizó un drenaje del absceso, principalmente por incisión (81,7%). Sólo en el 13,1% de los pacientes se requirió un segundo drenaje. Conclusión: El absceso periamigdalino es una causa importante de consulta en los servicios de urgencia, siendo más frecuente en el adulto joven. El drenaje del absceso asociado a un tratamiento antibiótico endovenoso y/o vía oral presenta un excelente pronóstico.

ABSTRACT Introduction: Peritonsillar abscesses are an important cause of emergency consults in the otorhinolaryngology department. Its management includes use of antibiotics and drainage of the abscess. Aim: To describe and analyze the clinical characteristics, epidemiology, and management of peritonsillar abscesses at the Dr. Sótero del Río Health Center. Material and method: Retrospective and descriptive study of all patients presenting with a peritonsillar abscess between the years 2013 and 2016. Variables analyzed include demographics, signs and symptoms, use of antibiotics, drainage, and persistence of the disease. Results: This series includes 122 patients, with a mean age of 29 years; 19.6% are pediatric patients. Clinically, patients presented mainly with odynophagia (62.7%), muffled voice (32%), fever (27%), and trismus (27%). On physical examination, swelling of the tonsillar pillar (67.2%), uvula deviation (41.8%), trismus (26.2%), and white patches on tonsil (18.9%) were observed. The latter finding was more common in children. Forty-six percent of the patients received an antibiotic treatment previous to consulting at the emergency department, and 35.7% received steroids at the emergency department. The majority (92%) had the abscess drained, mainly by incision (81.7%). Only 13.1% of the patients required a second drainage. Conclusion: Peritonsillar abscess is a common presentation at the emergency department, seen primarily in young adults. The prognosis is excellent with drainage of the abscess associated with an intravenous and/or oral antibiotic treatment.