Microscale is key to model current and future Maritime Antarctic vegetation.

Despite being one of the most pristine regions in the world, Antarctica is currently also one of the most vulnerable to climate change. Antarctic vegetation comprises mostly lichens and bryophytes, complemented in some milder regions of Maritime Antarctica by two vascular plant species. Shifts in the spatial patterns of these three main vegetation groups have already been observed in response to climate change, highlighting the urgent need for the development of comprehensive large-scale ecological models of the effects of climate change. Besides climate, Antarctic terrestrial vegetation is also strongly influenced by non-climatic microscale conditions related to abiotic and biotic factors. Nevertheless, the quantification of their importance in determining vegetation patterns remains unclear. The objective of this work was to quantify the importance of abiotic and biotic microscale conditions in determining the spatial cover patterns of the major functional types, lichens, vascular plants and bryophytes, explicitly determining the likely confinement of each functional type to the microscale conditions, i.e., their ecological niche. Microscale explained >60 % of the spatial variation of lichens and bryophytes and 30 % of vascular plants, with the niche analysis suggesting that each of the three functional types may be likely confined to specific microscale conditions in the studied gradient. Models indicate that the main microscale ecological filters are abiotic but show the potential benefits of including biotic variables and point to the need for further clarification of vegetation biotic interactions' role in these ecosystems. Altogether, these results point to the need for the inclusion of microscale drivers in ecological models to track and forecast climate change effects, as they are crucial to explain present vegetation patterns in response to climate, and for the interpretation of ecological model results under a climate change perspective.

Pulmonary biological glue embolism after endoscopic repair of gastric varices - A case report.

Cyanoacrylate injection is widely used to treat hemorrhagic gastric varices. A pulmonary glue embolism is an unusual but potentially fatal complication. We present a case of a 51-year-old man with a history of alcoholic hepatic cirrhosis Child-Pugh B, who had an acute pulmonary embolism with sudden cardiorespiratory collapse due to biological glue injection used for the emergent repair of bleeding gastric varices. After the restoration of respiratory and hemodynamic parameters, he was admitted to the intensive care unit and the pulmonary biological glue emboli were documented with computed tomography scan. A high index of suspicion for this entity is essential in patients submitted to endoscopic sclerotherapy. Some might be asymptomatic or mildly symptomatic, while others might present with cardiorespiratory collapse.

Antitumoral and Immunogenic Capacity of ß-D-Glucose-Reduced Silver Nanoparticles in Breast Cancer.

Immunogenic cell death (ICD) is a type of cell death capable of stimulating immunity against cancer through danger signals that lead to an adaptive immune response. Silver nanoparticles (AgNPs) have been shown to have a cytotoxic effect on cancer cells; however, their mechanism of action is not fully understood. The present study synthesized, characterized, and evaluated the cytotoxic effect of beta-D-glucose-reduced AgNPs (AgNPs-G) against breast cancer (BC) cells in vitro; and assess the immunogenicity of cell death in vitro and in vivo. The results showed that AgNPs-G induce cell death in a dose-dependent manner on BC cell lines. In addition, AgNPs show antiproliferative effects by interfering with the cell cycle. Regarding the detection of damage-associated molecular patterns (DAMPs), it was found that treatment with AgNPs-G induces calreticulin exposure and the release of HSP70, HSP90, HMGB1, and ATP. In vivo, prophylactic vaccination did not prevent tumor establishment; however, tumor weight was significantly lower in AgNPs-G vaccinated mice, while the survival rate increased. In conclusion, we have developed a new method for the synthesis of AgNPs-G, with in vitro antitumor cytotoxic activity on BC cells, accompanied by the release of DAMPs. In vivo, immunization with AgNPs-G failed to induce a complete immune response in mice. Consequently, additional studies are needed to elucidate the mechanism of cell death that leads to the design of strategies and combinations with clinical efficacy.

Dark Proteome Database: Studies on Disorder.

There is a misconception that intrinsic disorder in proteins is equivalent to darkness. The present study aims to establish, in the scope of the Swiss-Prot and Dark Proteome databases, the relationship between disorder and darkness. Three distinct predictors were used to calculate the disorder of Swiss-Prot proteins. The analysis of the results obtained with the used predictors and visualization paradigms resulted in the same conclusion that was reached before: disorder is mostly unrelated to darkness.

Monitoring recent changes of vegetation in Fildes Peninsula (King George Island, Antarctica) through satellite imagery guided by UAV surveys.

Mapping accurately vegetation surfaces in space and time in the ice-free areas of Antarctica can provide important information to quantitatively describe the evolution of their ecosystems. Spaceborne remote sensing is the adequate way to map and evaluate multitemporal changes on the Antarctic vegetation at large but its nature of occurrence, in relatively small and sparse patches, makes the identification very challenging. The inclusion of an intermediate scale of observation between ground and satellite scales, provided by Unmanned Aerial Vehicles (UAV) imagery, is of great help not only for their effective classification, but also for discriminating their main communities (lichens and mosses). Thus, this paper quantifies accurately recent changes of the vegetated areas in Fildes Peninsula (King George Island, Antarctica) through a novel methodology based on the integration of multiplatform data (satellite and UAV). It consists of multiscale imagery (spatial resolution of 2 m and 2 cm) from the same period to create a robust classifier that, after intensive calibration, is adequately used in other dates, where field reference data is scarce or not available at all. The methodology is developed and tested with UAV and satellite data from 2017 showing overall accuracies of 96% and kappa equal to 0.94 with a SVM classifier. These high performances allow the extrapolation to a pair of previous dates, 2006 and 2013, when atmospherically clear very high-resolution satellite imagery are available. The classification allows verifying a loss of the total area of vegetation of 4.5% during the 11-year time period under analysis, which corresponds to a 10.3% reduction for Usnea sp. and 9.8% for moss formations. Nevertheless, the breakdown analysis by time period shows a distinct behaviour for each vegetation type which are evaluated and discussed, namely for Usnea sp. whose decline is likely to be related to changing snow conditions.

Peribulbar block combined with general anesthesia in babies undergoing laser treatment for retinopathy of prematurity: a retrospective analysis / Bloqueio peribulbar combinado com anestesia geral em bebês submetidos a tratamento a laser para retinopatia da prematuridade: uma análise retrospectiva

Abstract Background and objectives Currently there is no agreement regarding which one is the most adequate anesthetic technique for the treatment of retinopathy of prematurity. Peribulbar block may reduce the incidence of oculocardiac reflex and postoperative apnea. The goal of this study was to report the outcomes of peribulbar block, when combined with general anesthesia, for the laser treatment for retinopathy of prematurity, in premature babies. Methods A retrospective analysis of anesthetic records of all babies who underwent laser treatment for retinopathy of prematurity from January 2008 through December 2015 in a tertiary hospital was performed. Results During that period a total of six babies was submitted to laser treatment for retinopathy of prematurity, all under peribulbar block combined with general anesthesia. A single infratemporal injection of 0.15 mL.kg−1 per eye ropivacaine 1% or 0.75% was performed. At the end of the procedure, all babies resumed spontaneous ventilation. No perioperative complications were reported. Conclusions Peribulbar block was a safe anesthetic technique in our sample considered.

Resumo Justificativa e objetivos Até o momento não há um consenso sobre a técnica anestésica mais adequada para o tratamento de retinopatia da prematuridade. O bloqueio peribulbar pode reduzir a incidência de reflexo oculocardíaco e apneia no pós-operatório. O objetivo deste estudo foi relatar os resultados do bloqueio peribulbar, quando combinado com anestesia geral, para o tratamento a laser de retinopatia da prematuridade em bebês prematuros. Métodos Uma análise retrospectiva dos registros anestésicos de todos os bebês submetidos ao tratamento a laser para retinopatia da prematuridade de janeiro de 2008 a dezembro de 2015 foi realizada em um hospital terciário. Resultados Durante esse período, seis bebês foram submetidos ao tratamento a laser para retinopatia da prematuridade, todos sob bloqueio peribulbar combinado com anestesia geral. Uma injeção infratemporal única de ropivacaína a 1% ou 0,75% (0,15 mL.kg−1) foi administrada por olho. No fim do procedimento, todos os bebês retomaram a ventilação espontânea. Não foram relatadas complicações perioperatórias. Conclusões O bloqueio peribulbar foi uma técnica anestésica segura em nossa amostra considerada.

[Peribulbar block combined with general anesthesia in babies undergoing laser treatment for retinopathy of prematurity: a retrospective analysis]. / Bloqueio peribulbar combinado com anestesia geral em bebês submetidos a tratamento a laser para retinopatia da prematuridade: uma análise retrospectiva.

BACKGROUND AND OBJECTIVES: Currently there is no agreement regarding which one is the most adequate anesthetic technique for the treatment of retinopathy of prematurity. Peribulbar block may reduce the incidence of oculocardiac reflex and postoperative apnea. The goal of this study was to report the outcomes of peribulbar block, when combined with general anesthesia, for the laser treatment for retinopathy of prematurity, in premature babies. METHODS: A retrospective analysis of anesthetic records of all babies who underwent laser treatment for retinopathy of prematurity from January 2008 through December 2015 in a tertiary hospital was performed. RESULTS: During that period a total of six babies was submitted to laser treatment for retinopathy of prematurity, all under peribulbar block combined with general anesthesia. A single infratemporal injection of 0.15mL.kg-1 per eye ropivacaine 1% or 0.75% was performed. At the end of the procedure, all babies resumed spontaneous ventilation. No perioperative complications were reported. CONCLUSIONS: Peribulbar block was a safe anesthetic technique in our sample considered.

Evaluation of the use of very high resolution aerial imagery for accurate ice-wedge polygon mapping (Adventdalen, Svalbard).

The main objective of this paper is to verify the accuracy of delineating and characterizing ice-wedge polygonal networks with features exclusively extracted from remotely sensed images of very high resolution. This kind of mapping plays a key role for quantifying ice-wedge degradation in warming permafrost. The evaluation of mapping a network is performed in this study with two sets of aerial images that are compared to ground reference data determined by fieldwork on the same network, located in Adventdalen, Svalbard (78°N). One aerial dataset is obtained from a photogrammetric survey with RGB+NIR imagery of 20cm/pixel, the other from an UAV (Unmanned Aerial Vehicle) survey that acquired RGB images of 6cm/pixel of spatial resolution. Besides evaluating the degree of matching between the delineations, the morphometric and topological features computed for the differently mapped versions of the network are also confronted, to have a more solid basis of comparison. The results obtained are similar enough to admit that remotely sensed images of very high resolution are an adequate support to provide extensive characterizations and classifications of this kind of patterned ground.

Accurate determination of surface reference data in digital photographs in ice-free surfaces of Maritime Antarctica.

The ice-free areas of Maritime Antarctica show complex mosaics of surface covers, with wide patches of diverse bare soils and rock, together with various vegetation communities dominated by lichens and mosses. The microscale variability is difficult to characterize and quantify, but is essential for ground-truthing and for defining classifiers for large areas using, for example high resolution satellite imagery, or even ultra-high resolution unmanned aerial vehicle (UAV) imagery. The main objective of this paper is to verify the ability and robustness of an automated approach to discriminate the variety of surface types in digital photographs acquired at ground level in ice-free regions of Maritime Antarctica. The proposed method is based on an object-based classification procedure built in two main steps: first, on the automated delineation of homogeneous regions (the objects) of the images through the watershed transform with adequate filtering to avoid an over-segmentation, and second, on labelling each identified object with a supervised decision classifier trained with samples of representative objects of ice-free surface types (bare rock, bare soil, moss and lichen formations). The method is evaluated with images acquired in summer campaigns in Fildes and Barton peninsulas (King George Island, South Shetlands). The best performances for the datasets of the two peninsulas are achieved with a SVM classifier with overall accuracies of about 92% and kappa values around 0.89. The excellent performances allow validating the adequacy of the approach for obtaining accurate surface reference data at the complete pixel scale (sub-metric) of current very high resolution (VHR) satellite images, instead of a common single point sampling.

El asesoramiento cardiológico a través de la telemedicina: experiencia en el estado Lara-Venezuela / Cardiologic support by telemedicine: experience in Lara State-Venezuela

La transmisión de electrocardiogramas por vía telefónica es una técnica ampliamente difundida en el mundo. Se describe la experiencia de 17 meses (marzo 2006-agosto 2007) de utilización de un sistema de transmisión de electrocardiogramas, desde 23 centros urbanos y suburbanos ubicados en el Estado Lara. Los electrocardiogramas son tomados y transmitidos por los médicos generales mediante equipos Aerotel ®, ubicados en los hospitales o ambulatorios, a la central de llamadas ubicada en Caracas. El cardiólogo de guardia transmite el electrocardiograma el cual es recibido e interpretado por el especialista de guardia de telemedicina. El trazo electrocardiográfico, interpretado es enviado en pocos minutos al médico referente vía Fax. Se realizaron 3.690 electrocardiogramas a 3.104 pacientes. El motivo de la realización del electrocardiograma fue en la mayoría de los casos, dolor torácico (25 por ciento) o hipertensión arterial (26 por ciento). Los electrocardiogramas con anormalidades alcanzaron el 65 por ciento. Los trastornos isquémicos representaron el porcentaje mayor de anormalidades (32 por ciento). De las arritmias, la de mayor frecuencia la fibrilación y el “flutter”auricular (43 por ciento). Los trastornos de conducción el bloqueo de rama derecha y el hemibloqueo anterior izquierdo ocuparon la mayor frecuencia (23 por ciento y 35 por ciento respectivamente). Los electrocardiogramas cuyo diagnóstico requirió una conducta inmediata alcanzaron a 428 electrocardiogramas, siendo los más frecuentes la fibrilación auricular y la lesión subepicárdica: 203 (47 por ciento) y 161 (38 por ciento respectivamente. Este estudio muestra la utilidad de un sistema de tele-electrocardiografía, que presta asesoramiento cardiológico a centros urbanos y suburbanos en los cuales no existen especialistas de manera permanente.

Telephone transmission of electrocardiograms is widely practiced around the world. This study describes the experience with a tele-electrocardiography system, over 17 months (March, 2006-August, 2007), in 23 urban and suburban centers located in Lara State. Electrocardiograms were obtained by general practitioners using Aerotel® devices located in clinics and hospitals and transmitted to a call center located in Caracas. There a receiving cardiologist interpreted the tracings. Within a few minutes the interpretation was sent back to the referring physician. A total of 3,690 electrocardiograms were obtained from 3,104 patients. The reason for obtaining an electrocardiogram in these patients was, in most cases, a presenting history of chest pain (25%) or a finding of arterial hypertension (26%). An abnormality was found in 65% of the tracings. Conduction disturbances accounted for the highest percentage (32%). Among rhythm disturbances, atrial fibrillation and flutter were present in 43% of the electrocardiograms. Right bund le branch block and left anterior hemiblock were the most frequent conduction abnormalities (23% and 35% respectively). There were 428 electrocardiographic diagnoses, resulting in an immediate intervention, of which atrial fibrillation and a subepicardial lesion accounted for 203 (47%) and 161 (38%) cases respectively. This study shows the utility of a tele-electrocardiography system, which provides cardiologic support to urban and suburban centers, where specialists arenot available.