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OBJECTIVES: This study aims to describe resting state networks (RSN) in patients with disorders of consciousness (DOC)s after acute severe traumatic brain injury (TBI). METHODS: Adult patients with TBI with a GCS score <8 who remained in a coma, minimally conscious state (MCS), or unresponsive wakefulness syndrome (UWS), between 2017 and 2020 were included. Blood-oxygen-level dependent imaging was performed to compare their RSN with 10 healthy volunteers. RESULTS: Of a total of 293 patients evaluated, only 13 patients were included according to inclusion criteria: 7 in coma (54%), 2 in MCS (15%), and 4 (31%) had an UWS. RSN analysis showed that the default mode network (DMN) was present and symmetric in 6 patients (46%), absent in 1 (8%), and asymmetric in 6 (46%). The executive control network (ECN) was present in all patients but was asymmetric in 3 (23%). The right ECN was absent in 2 patients (15%) and the left ECN in 1 (7%). The medial visual network was present in 11 (85%) patients. Finally, the cerebellar network was symmetric in 8 patients (62%), asymmetric in 1 (8%), and absent in 4 (30%). CONCLUSIONS: A substantial impairment in activation of RSN is demonstrated in patients with DOC after severe TBI in comparison with healthy subjects. Three patterns of activation were found: normal/complete activation, 2) asymmetric activation or partially absent, and 3) absent activation.
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Lesões Encefálicas Traumáticas , Transtornos da Consciência , Humanos , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/fisiopatologia , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Transtornos da Consciência/fisiopatologia , Transtornos da Consciência/etiologia , Transtornos da Consciência/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Imageamento por Ressonância Magnética , Idoso , Adulto Jovem , Descanso/fisiologia , Estado Vegetativo Persistente/fisiopatologia , Estado Vegetativo Persistente/diagnóstico por imagem , Estado Vegetativo Persistente/etiologiaRESUMO
The western or desert red bat, Lasiurusfrantzii, is a cryptic insectivore species distributed in the Neotropics from Mexico south through Central America to Panama. L.frantzii was long considered a subspecies of the red bat, Lasiurusblossevillii, but recently it was elevated to full-species status based on genetic information. Here we present evidence of the presence of L.frantzii in the Andean Region of Colombia, confirming the species' presence in South America; the new record, from 3836 m a.s.l., is also the highest elevation known for the species. We suggest that L.frantzii might be widely distributed in trans-Andean areas of Colombia, Ecuador, Venezuela, and perhaps Peru and Bolivia. However, a review and exploration of additional morphological traits to identify the species are necessary because of the uncertainty of the distribution of L.frantzii.
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The genus Molossops includes two monotypic species of insectivore bats distributed in South America: Molossopsneglectus and Molossopstemminckii. Both can be differentiated, based on sizes, M.temminckii being smaller (forearm less than 33 mm). Despite being monotypic, at least two additional subspecies have been described for M.temminckii, of which M.temminckiigriseiventer from the inter-Andean Valley of the Magdalena River in Colombia might represent a valid taxon. To test the taxonomic status of M.t.griseiventer, we reviewed specimens of M.temminckii from cis- and trans-Andean localities in Colombia. We used Cytochrome-b and Cytochrome Oxidase I comparisons to test the phylogenetic position of cis- and trans-Andean samples and compared qualitative morphology, morphometric and bioacoustics. Our results show that M.t.griseiventer is differentiated from cis-Andean specimens, providing further evidence of its validity at the species level. Furthermore, M.temminckii (sensu stricto) is also distributed in Colombia, but both M.griseiventer and M.temminckii are allopatric, with the Andes acting as a barrier. The specific identity of the specimens from the Caribbean Region of Colombia needs a new evaluation, but our results clearly show that the diversity of Molossops is underestimated.
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Background: In Central America and the Caribbean, multiple myeloma (MM) patients face significant barriers to diagnosis and treatment. The aim of this study is to describe the current situation of MM in the region, discuss the current barriers to timely diagnosis and proper treatment, and develop consensus recommendations to address these issues. Methods: Nine experts from five countries took part in a virtual consensus meeting on MM in Central America and the Caribbean. During the meeting, experts analyzed the disease burden, the current conditions for disease management, and access to treatment in the region. The participants reached a consensus on the extent of the problem and the necessary measures. Results: Hard evidence on the incidence and prevalence of MM in the region is scarce, but the experts perceive an increase in MM cases. The lack of data on the direct and indirect costs at the local and regional levels obscures the impact of the disease and limits awareness among decision-makers. Most patients are diagnosed late and face long waiting times and geographical barriers to access treatment. Access to efficacious innovative therapies that increase survival time is limited due to access barriers within health systems. Conclusions: There was consensus on five recommendations: 1) to generate evidence; 2) to educate the public; 3) to increase timely diagnosis and facilitate access to treatment; 4) to promote interaction, collaboration, and participation among all sectors involved in the decision-making process; and 5) to guarantee timely access to new therapies.
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To determine the role of early acquisition of blood oxygen level-dependent (BOLD) signals and diffusion tensor imaging (DTI) for analysis of the connectivity of the ascending arousal network (AAN) in predicting neurological outcomes after acute traumatic brain injury (TBI), cardiopulmonary arrest (CPA), or stroke. A prospective analysis of 50 comatose patients was performed during their ICU stay. Image processing was conducted to assess structural and functional connectivity of the AAN. Outcomes were evaluated after 3 and 6 months. Nineteen patients (38%) had stroke, 18 (36%) CPA, and 13 (26%) TBI. Twenty-three patients were comatose (44%), 11 were in a minimally conscious state (20%), and 16 had unresponsive wakefulness syndrome (32%). Univariate analysis demonstrated that measurements of diffusivity, functional connectivity, and numbers of fibers in the gray matter, white matter, whole brain, midbrain reticular formation, and pontis oralis nucleus may serve as predictive biomarkers of outcome depending on the diagnosis. Multivariate analysis demonstrated a correlation of the predicted value and the real outcome for each separate diagnosis and for all the etiologies together. Findings suggest that the above imaging biomarkers may have a predictive role for the outcome of comatose patients after acute TBI, CPA, or stroke.
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Transtornos da Consciência , Vias Neurais , Adulto , Idoso , Nível de Alerta , Biomarcadores , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Lesões Encefálicas/fisiopatologia , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico , Coma/diagnóstico por imagem , Coma/etiologia , Coma/fisiopatologia , Estado de Consciência/fisiologia , Transtornos da Consciência/diagnóstico por imagem , Transtornos da Consciência/etiologia , Transtornos da Consciência/fisiopatologia , Imagem de Tensor de Difusão , Feminino , Parada Cardíaca/complicações , Parada Cardíaca/diagnóstico , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Saturação de Oxigênio , Prognóstico , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnósticoRESUMO
Las evaluaciones rápidas de biodiversidad son la fuente de información más común sobre biodiversidad en el noroccidente amazónico en Colombia debido a que los recursos y la logística son limitados. Estas evaluaciones son esenciales para tomar decisiones ambientales en esta área que ha sido impactada por la transformación de sus ecosistemas naturales. Diferentes evaluaciones locales rápidas con cámaras trampa de mamíferos medianos y grandes (MMG) se han realizado en el noroccidente Amazónico en Colombia, pero estas son difícilmente comparables. Nosotros recolectamos la información de 16 evaluaciones rápidas de MMG para proporcionar la primera lista de MMG del noroccidente amazónico en Colombia. Adicionalmente, evaluamos la precisión de cuatro estimadores (ICE, Chao 2, Jackknife 1 y Jackknife 2) y el esfuerzo mínimo de muestreo para la estimación de la riqueza de MMG en estudios locales en esa región. Reportamos 26 especies de MMG para la Amazonía colombiana (entre cinco y 13 especies por localidad), lo que es uns subestimación de la riqueza de MMG en la región. El mejor estimador para este tipo de estudios fue Jackknife 1, debido a su precisión y la baja influencia de singletons. Recomendamos un esfuerzo mínimo de muestreo de 350 cámaras trampa-día. Aunque las evaluaciones rápidas no proveen una estimación robusta de la riqueza de MMG, estas evaluaciones registran las especies más comunes (especies core) y la variación en su abundancia por localidad. Es necesario un mayor esfuerzo de muestreo para evaluar el efecto de la transformación del hábitat sobre los MMG, en especial sobre los parámetros poblacionales de las especies raras. (AU)
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Floresta Úmida , MamíferosRESUMO
Rapid assessments are the most common information source on biodiversity in the northwestern Amazon in Colombia due to limited resources and logistic constraints. These assessments are essential for decision-making on environmental policies in this region, that has been strongly impacted by the transformation of its natural ecosystems. Several local camera-trapping rapid assessments of medium and large-sized mammals (MLM) have been conducted in the Colombian Amazon, but they are difficult to compare. We analyzed information of 16 of these rapid assessments of MLM to provide the first list of MLM in the northwestern Amazon in Colombia. We also evaluated the accuracy of four estimators (ICE, Chao-2, Jackknife-1, and Jackknife-2), and the minimum sampling effort for the estimation of MLM richness in local surveys in the region. We report 26 species of MLM for the Colombian Amazon (between five and 13 species per locality), which is an underestimation of MLM richness in the region. The best estimator of MLM richness was the Jackknife-1, due to its precision and the lower influence of singletons. We recommend a minimum sampling effort of 350 camera trap-days. Although rapid assessments do not allow a robust estimation of MLM richness, they record the most common species (or core species) per locality and their abundance variation. The evaluation of the effect of habitat transformation on MLM and the estimation of population parameters of rare species require more intensive studies.(AU)
Las evaluaciones rápidas de biodiversidad son la fuente de información más común sobre biodiversidad en el noroccidente amazónico en Colombia debido a que los recursos y la logística son limitados. Estas evaluaciones son esenciales para tomar decisiones ambientales en esta área que ha sido impactada por la transformación de sus ecosistemas naturales. Diferentes evaluaciones locales rápidas con cámaras trampa de mamíferos medianos y grandes (MMG) se han realizado en el noroccidente Amazónico en Colombia, pero estas son difícilmente comparables. Nosotros recolectamos la información de 16 evaluaciones rápidas de MMG para proporcionar la primera lista de MMG del noroccidente amazónico en Colombia. Adicionalmente, evaluamos la precisión de cuatro estimadores (ICE, Chao 2, Jackknife 1 y Jackknife 2) y el esfuerzo mínimo de muestreo para la estimación de la riqueza de MMG en estudios locales en esa región. Reportamos 26 especies de MMG para la Amazonía colombiana (entre cinco y 13 especies por localidad), lo que es uns subestimación de la riqueza de MMG en la región. El mejor estimador para este tipo de estudios fue Jackknife 1, debido a su precisión y la baja influencia de singletons. Recomendamos un esfuerzo mínimo de muestreo de 350 cámaras trampa-día. Aunque las evaluaciones rápidas no proveen una estimación robusta de la riqueza de MMG, estas evaluaciones registran las especies más comunes (especies core) y la variación en su abundancia por localidad. Es necesario un mayor esfuerzo de muestreo para evaluar el efecto de la transformación del hábitat sobre los MMG, en especial sobre los parámetros poblacionales de las especies raras.(AU)
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Animais , Biodiversidade , Mamíferos/crescimento & desenvolvimento , Demografia , Floresta ÚmidaRESUMO
RESUMEN La Serranía de La Lindosa es una formación geomorfológica que presenta heterogeneidad en sus coberturas vegetales. Esta zona se encuentra en una situación contradictoria debido a que presenta una elevada biodiversidad, sin embargo, es uno de los actuales focos de deforestación más grandes de Colombia. A pesar de que se espera una alta diversidad de murciélagos en La Lindosa existe poca información publicada sobre este grupo. Este trabajo presenta los resultados de inventarios de murciélagos realizados durante cinco años en la Serranía de la Lindosa. Se compara la diversidad (riqueza, composición y estructura) de los ensamblajes de murciélagos en dos tipos principales de cobertura vegetal, los bosques húmedos y las sabanas casmófitas. Los inventarios recogen información de 735 murciélagos capturados, correspondientes a 46 especies. De estas, 14 especies se encontraron solamente en sabanas casmófitas, 11 en bosques húmedos y 19 en los dos tipos de vegetación. De esta manera, se evidencia una alta complementariedad en la composición de especies de murciélagos entre los dos tipos de vegetación. Adicionalmente, la estructura de los ensamblajes de murciélagos varió entre los dos ambientes. La abundancia entre las especies es más homogénea en las sabanas casmófitas con un mayor número de especies raras comparado con los bosques húmedos. En general, la alta diversidad de murciélagos de la Serranía de La Lindosa puede estar relacionada con la heterogeneidad en la vegetación, la presencia de diferentes tipos de cuevas, y la historia evolutiva de las especies de murciélagos asociados a la Región Guayana.
ABSTRACT The Serranía La Lindosa is a geomorphological formation with land cover heterogeneity. This area faces a contradictory situation because it has high biodiversity and provides several ecosystem services, and yet it is one of the current largest deforestation sites in Colombia. Bats is a taxonomic group with high expected diversity in La Lindosa, but there is little published information about this group. This paper presents the results of bat inventories carried out during five years in the Lindosa mountain range. Additionally, diversity is compared in terms of species richness, composition, and structure of bat assemblies in two main types ofvegetation cover evident in the area, which are humid forests and casmophytic savannas. Inventories collected information on 735 captured bats, corresponding to 46 species. Of these, 14 species were found only in casmophytic savannas, 11 in humid forests, and 19 in both types of vegetation. Thus, there is high complementarity in bat species composition between the two vegetation types. Additionally, the structure of bat assemblies varied between the two environments, with a proportional distribution of species abundance more homogeneous in casmophytic savannas than in forests. Besides, a higher number of rare species was found in casmophytic savannas. In general, the high diversity of bats of the Serranía de La Lindosa could be associated with vegetation heterogeneity, presence of different cave types and evolutionary history of bat species associated with the Guayana Region.
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Recent evidence on resting-state functional magnetic resonance imaging (rs-fMRI) suggests that healthy human brains have a temporal organization represented in a widely complex time-delay structure. This structure seems to underlie brain communication flow, integration/propagation of brain activity, as well as information processing. Therefore, it is probably linked to the emergence of highly coordinated complex brain phenomena, such as consciousness. Nevertheless, possible changes in this structure during an altered state of consciousness remain poorly investigated. In this work, we hypothesized that due to a disruption in high-order functions and alterations of the brain communication flow, patients with disorders of consciousness (DOC) might exhibit changes in their time-delay structure of spontaneous brain activity. We explored this hypothesis by comparing the time-delay projections from fMRI resting-state data acquired in resting state from 48 patients with DOC and 27 healthy controls (HC) subjects. Results suggest that time-delay structure modifies for patients with DOC conditions when compared with HC. Specifically, the average value and the directionality of latency inside the midcingulate cortex (mCC) shift with the level of consciousness. In particular, positive values of latency inside the mCC relate to preserved states of consciousness, whereas negative values change proportionally with the level of consciousness in patients with DOC. These results suggest that the mCC may play a critical role as an integrator of brain activity in HC subjects, but this role vanishes in an altered state of consciousness.
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Encéfalo/diagnóstico por imagem , Transtornos da Consciência/diagnóstico por imagem , Estado de Consciência/fisiologia , Imageamento por Ressonância Magnética/métodos , Oxigênio/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/fisiopatologia , Transtornos da Consciência/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Descanso , Índice de Gravidade de Doença , Fatores de Tempo , Adulto JovemRESUMO
INTRODUCTION: Functional connectivity alterations within individual resting state networks (RSNs) are linked to disorders of consciousness (DOC). If these alterations influence the interaction quality with other RNSs, then, brain alterations in patients with DOC would be characterized by connectivity changes in the large-scale model composed of RSNs. How are functional interactions between RSNs influenced by internal alterations of individual RSNs? Do the functional alterations induced by DOC change some key properties of the large-scale network, which have been suggested to be critical for the consciousness emergence? Here, we use network analysis to measure functional connectivity in patients with DOC and address these questions. We hypothesized that network properties provide descriptions of brain functional reconfiguration associated with consciousness alterations. METHODS: We apply nodal and global network measurements to study the reconfiguration linked with the disease severity. We study changes in integration, segregation, and centrality properties of the functional connectivity between the RSNs in subjects with different levels of consciousness. RESULTS: Our analysis indicates that nodal measurements are more sensitive to disease severity than global measurements, particularly, for functional connectivity of sensory and cognitively related RSNs. CONCLUSION: The network property alterations of functional connectivity in different consciousness levels suggest a whole-brain topological reorganization of the large-scale functional connectivity in patients with DOC.