Genetic rescue by distant trees mitigates qualitative pollen limitation imposed by fine-scale spatial genetic structure.

Restricted seed dispersal frequently leads to fine-scale spatial genetic structure (i.e., FSGS) within plant populations. Depending on its spatial extent and the mobility of pollinators, this inflated kinship at the immediate neighbourhood can critically impoverish pollen quality. Despite the common occurrence of positive FSGS within plant populations, our knowledge regarding the role of long-distance pollination preventing reproductive failure is still limited. Using microsatellite markers, we examined the existence of positive FSGS in two low-density populations of the tree Pyrus bourgaeana. We also designed controlled crosses among trees differing in their kinship to investigate the effects of increased local kinship on plant reproduction. We used six pollination treatments and fully monitored fruit production, fruit and seed weight, proportion of mature seeds per fruit, and seed germination. Our results revealed positive FSGS in both study populations and lower fruit initiation in flowers pollinated with pollen from highly-genetically related individuals within the neighbourhood, with this trend intensifying as the fruit development progressed. Besides, open-pollinated flowers exhibited lower performance compared to those pollinated by distant pollen donors, suggesting intense qualitative pollen limitation in natural populations. We found positive fine-scale spatial genetic structure is translated into impoverished pollen quality from nearby pollen donors which negatively impacts the reproductive success of trees in low-density populations. Under this scenario of intrapopulation genetic rescue by distant pollen donors, the relevance of highly-mobile pollinators for connecting spatially and genetically distant patches of trees may be crucial to safeguarding population recruitment.

Strong among population variation in frugivory strength by functional diverse frugivores: a 'reciprocal translocation' experiment.

Fruit-frugivore interactions are critical for the dynamics and evolution of many plant communities. The strength of the interactions between a given plant species and different frugivore guilds (e.g., seed dispersers, seed predators) often vary in space due to changes in plant extrinsic factors (e.g., frugivore abundances) and plant traits (e.g., fruit size and reward). By reciprocally translocating Pyrus bourgaeana ripe fruits representative of five Mediterranean localities during 2 consecutive years, we experimentally quantified guild-specific variations among populations in frugivory strength, while accounted for plant-intrinsic and- extrinsic factors. Though overall fruit removal did not differ among localities, there were strong guild-specific differences in fruit removal strength. Fruit removal by pulp feeders, seed dispersers, and fruit predators varied among populations up to 8.5-, 5.6-, and 4.0-folds, respectively. These strong variations seemed mediated by changes in frugivore relative abundances rather than on availability of alternative fruits. As expected, all fruit traits considered (e.g., fruit size, pulp amount) markedly varied among tree populations. However, no frugivore guild showed preference for fruits from any locality, suggesting that fruit traits did not contribute much to differences in frugivory strength among populations. Since the functional diverse frugivore guilds played contrasting roles in P. bourgaeana dynamics (e.g., seed dispersal vs. seed predation), our study highlights the importance of accounting for functional diversity in frugivore guilds when estimating spatial variations in the strenght of seed dispersal. This investigation also illustrates a neglected but widely applicable experimental approach to identify the relative importance of extrinsic factors and fruit traits in mediating fruit-frugivore interactions.

Multidate, multisensor remote sensing reveals high density of carbon-rich mountain peatlands in the páramo of Ecuador.

Tropical peatlands store a significant portion of the global soil carbon (C) pool. However, tropical mountain peatlands contain extensive peat soils that have yet to be mapped or included in global C estimates. This lack of data hinders our ability to inform policy and apply sustainable management practices to these peatlands that are experiencing unprecedented high rates of land use and land cover change. Rapid large-scale mapping activities are urgently needed to quantify tropical wetland extent and rate of degradation. We tested a combination of multidate, multisensor radar and optical imagery (Landsat TM/PALSAR/RADARSAT-1/TPI image stack) for detecting peatlands in a 2715 km2 area in the high elevation mountains of the Ecuadorian páramo. The map was combined with an extensive soil coring data set to produce the first estimate of regional peatland soil C storage in the páramo. Our map displayed a high coverage of peatlands (614 km2 ) containing an estimated 128.2 ± 9.1 Tg of peatland belowground soil C within the mapping area. Scaling-up to the country level, páramo peatlands likely represent less than 1% of the total land area of Ecuador but could contain as much as ~23% of the above- and belowground vegetation C stocks in Ecuadorian forests. These mapping approaches provide an essential methodological improvement applicable to mountain peatlands across the globe, facilitating mapping efforts in support of effective policy and sustainable management, including national and global C accounting and C management efforts.

Latitudinal gradients in seed predation persist in urbanized environments.

Urbanization is creating a new global biome, in which cities and suburbs around the world often resemble each other more than the local natural areas they replaced. But while urbanization can profoundly affect ecology at local scales, we know little about whether it disrupts large-scale ecological patterns. Here we test whether urbanization disrupts a macroecological pattern central to ecological and evolutionary theory: the increase in seed predation intensity from high to low latitudes. Across 14,000 km of latitude spanning the Americas, we compared predation intensity on two species of standardized experimental seeds in urbanized and natural areas. In natural areas, predation on both seed species increased fivefold from high latitudes to the tropics, one of the strongest latitudinal gradients in species interactions documented so far. Surprisingly, latitudinal gradients in predation were equally strong in urbanized areas despite significant habitat modification. Nevertheless, urbanization did affect seed predation. Compared with natural areas, urbanization reduced overall predation and vertebrate predation, did not affect predation by invertebrates in general, and increased predation by ants. Our results show that macroecological patterns in predation intensity can persist in urbanized environments, even as urbanization alters the relative importance of predators and potentially the evolutionary trajectory of urban populations.

Vegetation structure and aboveground biomass of Páramo peatlands along a high-elevation gradient in the northern Ecuadorian Andes.

The high-elevation peatlands of the páramos of the northern Andes constitute a diverse environment that harbors large numbers of species and several types of plant communities along altitudinal, latitudinal, and environmental gradients. However, little is known about the structure and functioning of these ecosystems, including peatland vegetation types and their relative contribution to the production and accumulation of peat soils. In this paper we characterized the structure of peatland plant communities of the humid páramos of northern Ecuador by describing the distribution of plant growth-forms and their aboveground biomass patterns. Along an elevation gradient of 640 m we sampled vegetation in 16 peatlands and aboveground biomass in four peatlands. Three distinct peatland vegetation types were identified: High elevation Cushion peatlands, dominated by Plantago rigida and Distichia muscoides, Sedge and rush peatlands dominated by Carex spp. and Juncus spp., and Herbaceous and shrubby peatlands, with a more heterogenous and structurally complex vegetation. In terms of aboveground biomass, we found an 8-fold reduction in the higher peatlands compared to the lower sites, suggesting that the steep elevational gradients characteristic of Andean environments might be crucial in structuring the physiognomy and composition of peatland vegetation, either through its effects on temperature and other environmental factors, or through its effects on the age and development of soils. Additional studies are needed to evaluate the potential effects of temperature, hydrology, micro-topography, geological setting, and land-use, which are likely to influence vegetation patters in these peatlands.

Frontiers in páramo water resources research: A multidisciplinary assessment.

Interdisciplinary knowledge is necessary to achieve sustainable management of natural resources. However, research is still often developed in an exclusively disciplinary manner, hampering the capacity to holistically address environmental issues. This study focuses on páramo, a group of high-elevation ecosystems situated around ∼3000 to ∼5000 m a.s.l. in the Andes from western Venezuela and northern Colombia through Ecuador down to northern Peru, and in the highlands of Panama and Costa Rica in Central America. Páramo is a social-ecological system that has been inhabited and shaped by human activity since ∼10,000 years BP. This system is highly valued for the water-related ecosystem services provided to millions of people because it forms the headwaters of major rivers in the Andean-Amazon region, including the Amazon River. We present a multidisciplinary assessment of peer-reviewed research on the abiotic (physical and chemical), biotic (ecological and ecophysiological), and social-political aspects and elements of páramo water resources. A total of 147 publications were evaluated through a systematic literature review process. We found that thematically 58, 19, and 23 % of the analyzed studies are related to the abiotic, biotic, and social-political aspects of páramo water resources, respectively. Geographically, most publications were developed in Ecuador (71 % of the synthesized publications). From 2010 onwards, the understanding of hydrological processes including precipitation and fog dynamics, evapotranspiration, soil water transport, and runoff generation improved, particularly for the humid páramo of southern Ecuador. Investigations on the chemical quality of water generated by páramo are rare, providing little empirical support to the widespread belief that páramo environments generate water of high quality. Most ecological studies examined the coupling between páramo terrestrial and aquatic environments, but few directly assessed in-stream metabolic and nutrient cycling processes. Studies focused on the connection between ecophysiological and ecohydrological processes influencing páramo water balance are still scarce and mainly related to the dominant vegetation in the Andean páramo, i.e., tussock grass (pajonal). Social-political studies addressed páramo governance and the implementation and significance of water funds and payment for hydrological services. Studies directly addressing water use, access, and governance in páramo communities remain limited. Importantly, we found only a few interdisciplinary studies combining methodologies from at least two disciplines of different nature despite their value in supporting decision-making. We expect this multidisciplinary synthesis to become a milestone to foster interdisciplinary and transdisciplinary dialogue among individuals and entities involved in and committed to the sustainable management of páramo natural resources. Finally, we also highlight key frontiers in páramo water resources research, which in our view need to be addressed in the coming years/decades to achieve this goal.

Nitrate reduction over a Pd-Cu/MWCNT catalyst: application to a polluted groundwater.

The influence of the presence of inorganic and organic matter during the catalytic reduction of nitrate in a local groundwater over a Pd-Cu catalyst supported on carbon nanotubes was investigated. It was observed that the catalyst performance was affected by the groundwater composition. The nitrate conversion attained was higher in the experiment using only deionized water as solvent than in the case of simulated or real groundwater. With exception of sulphate ions, all the other solutes evaluated (chloride and phosphate ions and natural organic matter) had a negative influence on the catalytic activity and selectivity to nitrogen.

Case reports: symptomatic bilateral talonavicular coalition.

Congenital talonavicular coalition is reported less frequently than talocalcaneal or calcaneonavicular coalition and represent approximately 1% of all tarsal coalitions. Although reportedly transmitted as an autosomal-dominant disorder, tarsal coalition may be inherited as an autosomal-recessive trait. It has been associated with various orthopaedic anomalies, including symphalangism, clinodactyly, a great toe shorter than the second toe, clubfoot, calcaneonavicular coalition, talocalcaneal coalition, and a ball-and-socket ankle. Patients with talonavicular coalitions are usually asymptomatic and rarely undergo surgical treatment. We report the case of a 24-year-old woman with symptomatic bilateral talonavicular coalitions and previously unreported associated anomalies (nail hypoplasia and metatarsus primus elevatus) and review the relevant literature. The patient underwent surgery (calcaneocuboid joint distraction arthrodesis and a proximal plantar flexion osteotomy with a dorsal open wedge of the first metatarsal). At 1-year followup, she was pain-free with better alignment of both feet and showed radiographic consolidation of the arthrodesis. Although this condition is less likely to be clinically important than other tarsal fusions, it sometimes can be painful enough for the patient to undergo surgery.

Validating anthropogenic threat maps as a tool for assessing river ecological integrity in Andean-Amazon basins.

Anthropogenic threat maps are commonly used as a surrogate for the ecological integrity of rivers in freshwater conservation, but a clearer understanding of their relationships is required to develop proper management plans at large scales. Here, we developed and validated empirical models that link the ecological integrity of rivers to threat maps in a large, heterogeneous and biodiverse Andean-Amazon watershed. Through fieldwork, we recorded data on aquatic invertebrate community composition, habitat quality, and physical-chemical parameters to calculate the ecological integrity of 140 streams/rivers across the basin. Simultaneously, we generated maps that describe the location, extent, and magnitude of impact of nine anthropogenic threats to freshwater systems in the basin. Through seven-fold cross-validation procedure, we found that regression models based on anthropogenic threats alone have limited power for predicting the ecological integrity of rivers. However, the prediction accuracy improved when environmental predictors (slope and elevation) were included, and more so when the predictions were carried out at a coarser scale, such as microbasins. Moreover, anthropogenic threats that amplify the incidence of other pressures (roads, human settlements and oil activities) are the most relevant predictors of ecological integrity. We concluded that threat maps can offer an overall picture of the ecological integrity pattern of the basin, becoming a useful tool for broad-scale conservation planning for freshwater ecosystems. While it is always advisable to have finer scale in situ measurements of ecological integrity, our study shows that threat maps provide fast and cost-effective results, which so often are needed for pressing management and conservation actions.

A global perspective on tropical montane rivers.

Tropical montane rivers (TMR) are born in tropical mountains, descend through montane forests, and feed major rivers, floodplains, and oceans. They are characterized by rapid temperature clines and varied flow disturbance regimes, both of which promote habitat heterogeneity, high biological diversity and endemism, and distinct organisms' life-history adaptations. Production, transport, and processing of sediments, nutrients, and carbon are key ecosystem processes connecting high-elevation streams with lowland floodplains, in turn influencing soil fertility and biotic productivity downstream. TMR provide key ecosystem services to hundreds of millions of people in tropical nations. In light of existing human-induced disturbances, including climate change, TMR can be used as natural model systems to examine the effects of rapid changes in abiotic drivers and their influence on biodiversity and ecosystem function.

Síndrome de Sjögren: identificación de nuevos biomarcadores y mecanismos moleculares implicados en su fisiopatogénesis

Introducción: El Síndrome de Sjögren (SS) es una enfermedad autoinmune de carácter sistémico, que afecta principalmente al sistema glandular exocrino, generando un funcionamiento anormal de las glándulas lacrimales y salivales. Objetivo: proporcionar una actualización sobre la identificación de nuevos biomarcadores y mecanismos moleculares implicados en la fisiopatogénesis del SS. Método: Revisión narrativa de la literatura en diferentes bases de datos, mediante la búsqueda de términos descritos incluidos en los tesauros MESH y DeCs, para artículos publicados a partir del año 2018. Resultados: presentamos evidencia que destaca la identificación de nuevos biomarcadores y mecanismos implicados en la fisiopatogénesis del SS, describiendo las vías de: linfocitos B, catepsina S, cistatina C, quimioquina C-X3-C modificada de ligando 1, quimiocina regulada por activación del timo, células T, proteína morfogenética ósea 6, estimulación del receptor de oxitocina, receptor de zinc, calponina-3. Conclusión: los avances en la tecnología facilita el análisis detallado de la genética y fisiopatogénesis del SS, impulsando el desarrollo de terapias específicas. La búsqueda de biomarcadores no invasivos responde a las limitaciones de los métodos existentes y la invasividad de las biopsias salivales, prometiendo mejoras diagnósticas y terapéuticas.

Introduction: Sjögren's Syndrome (SS) is a systemic autoimmune disease that primarily affects the exocrine glandular system, leading to abnormal lacrimal and salivary gland function. Objective: To provide an update on identifying new biomarkers and molecular mechanisms involved in the pathogenesis of SS. Method: Narrative review of the literature in various databases, searching for terms included in the MESH and DeCs thesauri, for articles published since 2018. Results: We present evidence highlighting the identification of new biomarkers and mechanisms involved in the pathogenesis of SS, describing pathways of B lymphocytes, cathepsin S, cystatin C, modified C-X3-C chemokine ligand 1, thymus activation-regulated chemokine, T cells, bone morphogenetic protein 6, oxytocin receptor stimulation, zinc receptor, and calponin-3. Conclusion: Advances in technology facilitate detailed analysis of the genetics and pathogenesis of SS, driving the development of specific therapies. The search for non-invasive biomarkers is driven by the limitations of existing methods and the invasiveness of salivary gland biopsies, promising diagnostic and therapeutic improvements.

Seed predation increases from the Arctic to the Equator and from high to low elevations.

Species interactions have long been predicted to increase in intensity toward the tropics and low elevations because of gradients in climate, productivity, or biodiversity. Despite their importance for understanding global ecological and evolutionary processes, plant-animal interaction gradients are particularly difficult to test systematically across large geographic gradients, and evidence from smaller, disparate studies is inconclusive. By systematically measuring postdispersal seed predation using 6995 standardized seed depots along 18 mountains in the Pacific cordillera, we found that seed predation increases by 17% from the Arctic to the Equator and by 17% from 4000 meters above sea level to sea level. Clines in total predation, likely driven by invertebrates, were consistent across treeline ecotones and within continuous forest and were better explained by climate seasonality than by productivity, biodiversity, or latitude. These results suggest that species interactions play predictably greater ecological and evolutionary roles in tropical, lowland, and other less seasonal ecosystems.

Utilidad del citoquímico urinario en cuidados intensivos, una herramienta olvidada

El sedimento urinario es una herramienta utilizada hace tantos años para caracterizar manifestaciones renales de enfermedades primarias y secundarias, que es necesario realizar una estandarización y aprender a interpretar el mismo. En los pacientes ingresados a la unidad de cuidados intensivos, muchas veces no se realiza, o hay que tener en cuenta varios factores para su interpretación debido al estado hemodinámico del paciente a la filtración glomerular, la excreción tubular, la reabsorción de agua y los solutos además del equilibrio acido-base, los cuales pueden variar significativamente en pacientes en estado crítico con diferentes condiciones fisiopatológicas. Se presenta una revisión de las condiciones para la interpretación del urianálisis.

A urinary sediment is a tool used for years to characterize renal manifestations of primary and secondary diseases, which requires standardization and learning to interpret it. In patients admitted to the intensive care unit, it is often not performed, or several factors must be taken into account for its interpretation due to the patient's hemodynamic status, glomerular filtration, tubular excretion, water reabsorption, and solutes. In addition to the acid-base balance, which can vary significantly in critically ill patients with different pathophysiological conditions? A review of the conditions for the interpretation of urinalysis is presented.

Utilidad del citoquímico urinario en cuidados intensivos, una herramienta olvidada / The usefulness of urinary sediment in intensive care, a forgotten tool

El sedimento urinario es una herramienta utilizada hace tantos años para caracterizar manifestaciones renales de enfermedades primarias y secundarias, que es necesario realizar una estandarización y aprender a interpretar el mismo. En los pacientes ingresados a la unidad de cuidados intensivos, muchas veces no se realiza, o hay que tener en cuenta varios factores para su interpretación debido al estado hemodinámico del paciente a la filtración glomerular, la excreción tubular, la reabsorción de agua y los solutos además del equilibrio acido-base, los cuales pueden variar significativamente en pacientes en estado crítico con diferentes condiciones fisiopatológicas. Se presenta una revisión de las condiciones para la interpretación del urianálisis.

A urinary sediment is a tool used for years to characterize renal manifestations of primary and secondary diseases, which requires standardization and learning to interpret it. In patients admitted to the intensive care unit, it is often not performed, or several factors must be taken into account for its interpretation due to the patient's hemodynamic status, glomerular filtration, tubular excretion, water reabsorption, and solutes. In addition to the acid-base balance, which can vary significantly in critically ill patients with different pathophysiological conditions? A review of the conditions for the interpretation of urinalysis is presented.

Transferencia de trapecio inferior con injerto autólogo de semitendinoso y recto interno / Transfer of the lower trapezius muscle tendon augmented with semitendinosus and gracillis tendon

Existen múltiples opciones de tratamientos para las rupturas masivas irreparables posterosuperiores del manguito rotador. Describiremos la transferencia del trapecio inferior con aumentación utilizando semitendinoso y recto interno autólogos, bajo asistencia. De esta manera devolvemos el balance muscular y restablecemos las cuplas de fuerza para la correcta movilidad del hombro afectado. Esta técnica se realiza con dos incisiones y tres portales artroscópicos: la primera para la toma del recto interno y semitendinoso en la rodilla del mismo lado del hombro afectado (aumentación), y la segunda en la escápula para la toma del trapecio inferior y para el pasaje de los tendones al espacio subacromial y posterior fijación con anclas sin nudo

In massive irreparable posterosuperior rotator cuff ruptures, there are several options for treatment. We will describe the transfer of the lower trapezius muscle tendon augmented with semitendinosus and gracillis tendons autologous, under arthroscopic assistance. In this way, muscular balance is restored for correct shoulder mobility. This technique is performed with two incisions and three arthroscopic portals, the first for harvest of the gracillis and semitendinosus tendons, in the knee on the same side of the affected shoulder (augmentation) and the second in the scapula for the harvest of the lower trapezius muscle tendon, and for passage to the subacromial, and fixation with knotless anchors

Patterns of litter disappearance in a northern hardwood forest invaded by exotic earthworms.

A field study was conducted to evaluate the effects of exotic earthworm invasions on the rates of leaf litter disappearance in a northern hardwood forest in southcentral New York, USA. Specifically, we assessed whether differences in litter quality and the species composition of exotic earthworm communities affected leaf litter disappearance rates. Two forest sites with contrasting communities of exotic earthworms were selected, and disappearance rates of sugar maple and red oak litter were estimated in litter boxes in adjacent earthworm-free, transition, and earthworm-invaded plots within each site. After 540 days in the field, 1.7-3 times more litter remained in the reference plots than in the earthworm-invaded plots. In the earthworm-invaded plots, rates of disappearance of sugar maple litter were higher than for oak litter during the first year, but by the end of the experiment, the amount of sugar maple and oak litter remaining in the earthworm-invaded plots was identical within each site. The composition of the earthworm communities significantly affected the patterns of litter disappearance. In the site dominated by the anecic earthworm Lumbricus terrestris and the endogeic Aporrectodea tuberculata, the percentage of litter remaining after 540 days (approximately 17%) was significantly less than at the site dominated by L. rubellus and Octolasion tyrtaeum (approximately 27%). This difference may be attributed to the differences in feeding behavior of the two litter-feeding species: L. terrestris buries entire leaves in vertical burrows, whereas L. rubellus usually feeds on litter at the soil surface, leaving behind leaf petioles and veins. Our results showed that earthworms not only accelerate litter disappearance rates, but also may reduce the differences in decomposition rates that result from different litter qualities at later stages of decay. Similarly, our results indicate that earthworm effects on decomposition vary with earthworm community composition. Furthermore, because earthworm invasion can involve a predictable shift in community structure along invasion fronts or through time, the community dynamics of invasion are important in predicting the spatial and temporal effects of earthworm invasion on litter decomposition, especially at later stages of decay.

La enfermería de quirófano ante la Hipertermia Maligna. ¿Estamos preparados? / Surgical Nurse on Malignant Hyperthermia. Are we prepared?

OBJETIVO PRINCIPAL: Evaluar el conocimiento de la Hipertermia Maligna (HM) entre los profesionales de Enfermería de quirófano. METODOLOGÍA: Estudio descriptivo transversal con 169 profesionales de Enfermería de quirófano. RESULTADOS PRINCIPALES: La puntuación total de los cuestionarios alcanzó un promedio de 4,8 (±2,18) puntos sobre 10 totales. Disponer de un protocolo para la asistencia de episodios de HM, se relacionó de forma significativa con un conocimiento adecuado. CONCLUSIÓN PRINCIPAL: Los profesionales de Enfermería de quirófano presentan unos inadecuados niveles de conocimiento sobre la HM y su manejo. Es necesaria una mejora en la preparación de las enfermeras para atender a un paciente en crisis de HM

MAIN OBJECTIVE: Assessing knowledge levels of the surgical nurses regarding Malignant Hyperthermia (MH) and its management. METHODOLOGY: Cross-sectional descriptive study among 169 surgical nurses. MAIN RESULTS: The total score of the questionnaires reached an average of 4.8 (± 2.18) points out of 10 total. Having an standart operating procedute for the assistance of MH episodes was significantly related to adequate knowledge. MAIN CONCLUSION: Surgical nurses have inadequate levels on managing MH and delivering inmediate care. It is necessary to provide specific trainning on MH for surgical nurses to prepare them to safely assist patients suffering MH crisis

Adsorption of emerging pollutants on functionalized multiwall carbon nanotubes.

Adsorption of three representative emerging pollutants - 1,8-dichlorooctane, nalidixic acid and 2-(4-methylphenoxy)ethanol- on different carbon nanotubes was studied in order to determine the influence of the morphological and chemical properties of the materials on their adsorption properties. As adsorbents, multiwall carbon nanotubes (MWCNTs) without functionalization and with oxygen or nitrogen surface groups, as well as carbon nanotubes doped with nitrogen were used. The adsorption was studied in aqueous phase using batch adsorption experiments, results being fitted to both Langmuir and Freundlich models. The adsorption capacity is strongly dependent on both the hydrophobicity of the adsorbates and the morphology of the adsorbents. Thermodynamic parameters were determined observing strong interactions between the aromatic rings of the emerging pollutant and the nitrogen modified adsorbents.

Influence of nonnative earthworms on mycorrhizal colonization of sugar maple (Acer saccharum).

• Exotic earthworms can modify or eliminate surface organic (Oe/Oa) horizons in cold-temperate forest ecosystems and have profound effects on the forest soil environment, especially the rooting zone. • We examined the effects of earthworm colonization of northern hardwood forest soils on the abundance and morphology of mycorrhizal fungi associated with sugar maple ( Acer saccharum ). We compared mycorrhizal associations of areas of earthworm invasion with those of reference (no-worm) areas in Arnot Forest, central New York, USA. • The organic horizon in reference areas had higher mycorrhizal colonization rates and higher colonized root length than did surface layers in areas with active earthworm populations. Hyphal coils were more abundant and also formed a greater proportion of total fungal colonization in reference plots. Vesicles were more abundant and were a higher contribution to total colonization in earthworm plots, indicating a possible stress response to the presence of earthworms. • By affecting mycorrhizal colonization and morphology, earthworms may influence nutrient uptake capacity of dominant forest species. Our results suggest that a profound change in the mycorrhizal system will be one component of the potential ecosystem effects of invasion of new forest habitat by nonnative earthworms.

Rotura del biceps distal: evaluación de resultados con técnica de doble fijación / Distal biceps rupture: evaluation of results with double fixation technique

Introducción: La rotura del bíceps distal es una lesión poco frecuente producida por la aplicación de una fuerza excéntrica sobre el codo flexionado. El objetivo de este trabajo es analizar los resultados obtenidos para la reinserción del bíceps distal mediante técnica de doble fijación con botón de anclaje cortical y tornillo interferencial de biotenodesis a través de una incisión anterior única. Materiales y Métodos: Entre agosto de 2008 y febrero de 2013, registramos 19 casos de rotura del bíceps distal tratados quirúrgicamente por vía anterior limitada. Los 17 últimos casos consecutivos fueron tratados con doble fijación utilizando botón extracortical y tornillo de biotenodesis, y forman parte del estudio. Todos eran hombres, con una mediana de la edad de 41 años (rango 27-59). Los pacientes fueron evaluados con el Cuestionario DASH y el Puntaje Subjetivo/Objetivo de Andrews y Carson, y la fuerza de flexión y supinación se controló con la escala del British Medical Research Council modificada por Mackinnon y Dellon (M0-M5). Resultados: El cuestionario DASH arrojó un valor mediano de 1,7 (0-5,83) y el de Andrews y Carson, de 195 (170-200) para el total; con 15 resultados excelentes y 2 buenos. Todos consiguieron una fuerza M5 para flexión y supinación de antebrazo. El seguimiento tuvo una mediana de 12 meses (4-32). En dos pacientes, se registraron complicaciones, ambas con recuperación ad íntegrum. Conclusión: La técnica descrita ha demostrado ser confiable y eficaz, y permitió lograr resultados satisfactorios y una baja tasa de complicaciones. Nivel de evidencia: IV. Serie de Casos.

Background: The distal biceps rupture is an unusual lesion produced when an eccentric force is applied to the bent elbow. The aim of this work is to analyze the results for the reinsertion of the distal biceps with a double fixation technique of cortical button and biotenodesis interference screw through a single anterior incision. Methods: Between August 2008 and February 2013 we registered 19 cases of distal biceps rupture, surgically treated through an anterior limited procedure. The last 17 consecutive cases were treated with double fixation using an extracortical button and biotenodesis screw and are part of this study. All the patients were males with a median age of 41 years (range 27-59). The patients were evaluated using the DASH questionnaire and the subjective/ objective scoring system of Andrews and Carson, controlling the flexion and supination forces with the British Medical Research Council scale, modified by Mackinnon and Dellon (M0-M5). Results: DASH questionnaire obtained a median value of 1.7 (0-5.83), and the Andrews and Carson score had a median value of 195 (170-200) for the total; with 15 excellent results and 2 good results. All patients achieved a force of M5 in flexion and supination of the forearm. The follow-up had a median of 12 months (4-32). Complications were registered in two patients, both recovered ad integrum. Conclusion: The described technique proved to be both reliable and effective, giving satisfactory results with a low complication rate. Level of evidence: IV. Case Series.