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Carbohydrate reserves play a vital role in plant survival during periods of negative carbon balance. Under a carbon-limited scenario, we expect a trade-offs between carbon allocation to growth, reserves, and defense. A resulting hypothesis is that carbon allocation to reserves exhibits a coordinated variation with functional traits associated with the 'fast-slow' plant economics spectrum. We tested the relationship between non-structural carbohydrates (NSC) of tree organs and functional traits using 61 angiosperm tree species from temperate and tropical forests with phylogenetic hierarchical Bayesian models. Our results provide evidence that NSC concentrations in stems and branches are decoupled from plant functional traits. while those in roots are weakly coupled with plant functional traits. In contrast, we found that variation between NSC concentrations in leaves and the fast-slow trait spectrum was coordinated, as species with higher leaf NSC had trait values associated with resource conservative species, such as lower SLA, leaf N, and leaf P. We also detected a small effect of leaf habit on the variation of NSC concentrations in branches and roots. Efforts to predict the response of ecosystems to global change will need to integrate a suite of plant traits, such as NSC concentrations in woody organs, that are independent of the 'fast-slow' plant economics spectrum and that capture how species respond to a broad range of global change drivers.

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The waters around the Galápagos Marine Reserve (GMR) are important fishing grounds for authorized artisanal vessels fishing within the reserve as well as for national and foreign industrial fleets operating in the wider Ecuadorian Insular Exclusive Economic Zone (IEEZ). Although it was not originally designed for fisheries management, Automatic Identification System (AIS) data provides useful, open access, near real-time and high-resolution information that allows for increased monitoring, particularly around Marine Protected Areas (MPAs) and in Areas Beyond National Jurisdiction. This study uses AIS data provided by Global Fishing Watch to assess the spatial distribution and seasonal dynamics of fishing effort by vessel flag within the GMR and the IEEZ from 2012 to 2021. Based on kernel density estimation analysis, we determinate the core-use areas (50%) and spatial extent (95%) of fishing activities by fleets (Ecuadorian and foreign), gear types and seasons (warm, from December to May; and cold, from June to November). Our results show that the Ecuadorian fleet recorded the most observed fishing hours in the study area, with 32,829 hours in the IEEZ and 20,816 hours within the GMR. The foreign flags with the most observed fishing hours in the IEEZ were Panama (3,245 hours) and Nicaragua (2,468.5 hours), while in the GMR were the 'Unknown flag' (4,991.4 hours) and Panama (133.7 hours). Vessels fished employing different fishing gears, but the waters of the GMR and IEEZ were mostly targeted by tuna purse-seiners and drifting longlines. The spatial distribution of the fishing effort exhibits marked seasonal variability, likely influenced by seasonal migrations of target species such as tunas (e.g., Thunnus albacares, T. obesus and Katsuwonus pelamis), marlins (e.g., Makaira nigricans) and sharks (e.g., Alopias pelagicus). The collection and use of this type of spatial and seasonal information is an essential step to understand the dynamics of fishing activities in national waters and improve fisheries management, particularly in less studied areas and fisheries.

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One foundational assumption of trait-based ecology is that traits can predict species demography. However, the links between traits and demographic rates are, in general, not as strong as expected. These weak associations may be due to the use of traits that are distantly related to performance, and/or the lack of consideration of size-related variations in both traits and demographic rates. Here, we examined how wood traits were related to demographic rates in 19 tree species from a lowland forest in eastern Amazonia. We measured 11 wood traits (i.e. structural, anatomical and chemical traits) in sapling, juvenile and adult wood; and related them to growth and mortality rates (MR) at different ontogenetic stages. The links between wood traits and demographic rates changed during tree development. At the sapling stage, relative growth rates (RGR) were negatively related to wood specific gravity (WSG) and total parenchyma fractions, while MR decreased with radial parenchyma fractions, but increased with vessel lumen area (VA). Juvenile RGR were unrelated to wood traits, whereas juvenile MR were negatively related to WSG and axial parenchyma fractions. At the adult stage, RGR scaled with VA and wood potassium concentrations. Adult MR were not predicted by any trait. Overall, the strength of the trait-demography associations decreased at later ontogenetic stages. Our results indicate that the associations between traits and demographic rates can change as trees age. Also, wood chemical or anatomical traits may be better predictors of growth and MR than WSG. Our findings are important to expand our knowledge on tree life-history variations and community dynamics in tropical forests, by broadening our understanding on the links between wood traits and demography during tree development.

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Wood density (WD) is a key functional trait related to ecological strategies and ecosystem carbon dynamics. Despite its importance, there is a considerable lack of information on WD in tropical Andean forests, particularly regarding its relationship with forest succession and ecosystem carbon cycling. Here, we quantified WD in 86 upper Andean tree and shrub species in central Colombia, with the aim of determining how WD changes with forest succession and how it is related to productivity. We hypothesized that WD will increase with succession because early successional forests will be colonized by acquisitive species, which typically have low WD, while the shaded understory of older forests should favor higher WD. We measured WD in 481 individuals from 27 shrub and 59 tree species, and quantified aboveground biomass (AGB), canopy height, net primary production (NPP) and species composition and abundance in 14, 400-m2, permanent plots. Mean WD was 0.513 ± 0.114 (g/cm3), with a range between 0.068 and 0.718 (g/cm3). Shrubs had, on average, higher WD (0.552 ± 0.095 g/cm3) than trees (0.488 ± 0.104 g/cm3). Community weighted mean WD (CWMwd) decreased with succession (measured as mean canopy height, AGB, and basal area); CWMwd also decreased with aboveground NPP and stem growth. In contrast, the percentage of NPP attributed to litter and the percent of shrubs in plots increased with CWMwd. Thus, our hypothesis was not supported because early successional forests had higher CWMwd than late successional forests. This was related to a high proportion of shrubs (with high WD) early in succession, which could be a consequence of: 1) a low seed availability of trees due to intense land use in the landscape and/or 2) harsh abiotic conditions early in succession that filter out trees. Forest with high CWMwd had a high %NPP attributed to litter because they were dominated by shrubs, which gain little biomass in their trunks. Our findings highlight the links between WD, succession and carbon cycling (biomass and productivity) in this biodiversity hotspot. Thus, WD is an important trait that can be used to understand upper Andean forest recovery and improve forest restoration and management practices.

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INTRODUCTION: The association of APOL1 risk variants with cardiovascular risk and cardiovascular disease (CVD) in observational and clinical trials has had inconsistent results. We aim to assess the relationship between the presence of APOL1 risk variants and the CVD risk in Afro-descendant patients with end-stage renal disease (ESRD). METHODS: We performed an observational, cross-sectional study of Afro-descendant adult patients with ESRD who were on the waitlist for a kidney transplant. Associations of APOL1 genotypes (high-risk [HR] = 2 alleles; low-risk [LR] = 0 or 1 allele) with cardiovascular risk were the primary clinical endpoint. The relation was evaluated using univariate and multivariate analysis. RESULTS: We enrolled a total of 102 patients with ESRD; 37% (38 patients) had APOL1 HR status with two alleles in homozygous (G1/G1 = 21 and G2/G2 = 3) or compound heterozygote (G1/G2 = 14) form and 63% (64 patients) had APOL1 LR status. No significant association was found between HR APOL1 genotypes and high cardiovascular risk (in adjusted Colombia Framingham Risk Score). APOL1 HR versus LR variants were not independently associated with left ventricular hypertrophy or systolic dysfunction. No cardiovascular deaths occurred during the follow-up. CONCLUSION: In Afro-descendent patients with ESRD, APOL1 HR status is not associated with the increase in cardiovascular risk profile and metabolic disturbances.

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Contexto: los pacientes con trasplante de riñón parecen tener un riesgo particularmente alto de enfermedad grave por COVID-19 debido a la inmunosupresión y la presencia de comorbilidades. Objetivo: describir las características clínicas, paraclínicas y desenlaces de los pacientes trasplantados renales que presentan infección por SARS-COV-2 en un hospital de cuarto nivel en Cali, Colombia. Metodología: realizamos un estudio observacional de receptores de trasplante renal con infección por SARS-CoV-2 ingresados ​​en la Fundación Valle del Lili, de junio a diciembre del 2020. Para ser elegibles en el estudio, los pacientes debían presentar síntomas compatibles, RT-PCR positiva y manejo hospitalario. Se excluyó a los pacientes asintomáticos. Resultados: inscribimos a un total de 50 pacientes, donde el 64 % eran hombres y la edad media fue de 53,5 años (rango 46-60). Las comorbilidades fueron: 36 (70 %) con hipertensión, 16 (32 %) con diabetes mellitus y 5 (10 %) con obesidad y los regímenes inmunosupresores más comunes fueron: tacrolimus, micofenolato y prednisona. La mediana de tiempo desde el inicio de los síntomas hasta la RT-PCR positiva fue de siete días. Los síntomas iniciales más comunes fueron fiebre (64 %), fatiga (58%), tos (44%) y disnea (36%). Los niveles basales de proteína C reactiva (PCR) fueron de 6,43 mg/dl (3,25-11,22), la mediana del recuento de linfocitos fue de 785 mm3/uL (550-1230), el dímero D basal fue de 0,767 ug/ml (0,484-1153,5) y el nivel medio de ferritina fue de 1011 ng/ml (670-2145). El 40 % desarrolló lesión renal aguda (20 pacientes), de los cuales 11 pacientes necesitaron terapia de remplazo renal, 6 de los pacientes fallecieron (12 %), 4/6 por insuficiencia multiorgánica relacionada con la sepsis y 2/6 por el síndrome de dificultad respiratoria agudo (SDRA). Conclusiones: las complicaciones mayores como la lesión renal aguda, el síndrome de dificultad respiratoria aguda y la mortalidad relacionada con la infección por COVID-19 observadas en nuestro estudio son significativas, pero menos frecuentes que las reportadas en otros países.

Background: Patients with kidney transplants seem to be at particularly high risk for severe COVID19 disease due to their impaired immune responses and comorbidities. Purpose: This study aims to describe kidney transplant patients' clinical characteristics and outcomes with SARSCOV-2 infection in a fourth-level hospital in Cali, Colombia. Methodology: We performed an observational study of kidney transplant recipients with SARS-CoV2 infection admitted at Fundación Valle del Lili from June to December 2020. To be eligible for this study, patients have symptoms compatible, a positive RT-PCR and inpatient management. Asymptomatic patients were excluded. Results: We enrolled a total of 50 patients. 64% were male, and the median age was 53.5 years (range 46-60). The comorbidities were 36 (70%) hypertension, 16 (32%) diabetes mellitus, 5 (10%) obesity. The most common immunosuppressive regimen was tacrolimus, mycophenolate and prednisone. The median time from symptoms onset to the positive RT-PCR was 7 days. The most common initial symptom was fever (64%), and fatigue (58%), cough (44%) and dyspnea (36%). Baseline levels of CRP was 6.43 mg/dL (3.25-11.22). The median lymphocyte count was 785 mm3/uL (550-1230). Baseline D-Dimer was 0.767 ug/ml (0.484-1153.5), ferritin median level was 1011ng/ml (670-2145). Six of the patients died (12%), 4/6 were by sepsis-related multi-organ failure and 2/6 were by ARDS. Conclusions: Major complications such as acute kidney injury, acute respiratory distress syndrome and mortality related to COVID-19 infection observed in our study are lower than those reported in other countries.

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Coastal habitats are essential for ecological processes and provide important ecosystem services. The Galapagos archipelago has a wide diversity of ichthyofauna which preservation guarantees the functioning of the marine ecosystem. In this study, we used ecological and taxonomic indices as well as multivariate analysis to identify spatiotemporal changes in fish community structure in coastal habitats of San Cristóbal Island in the southeastern Galapagos archipelago. We analyzed how the patterns of variability were related to the abiotic conditions (substrate, sea temperature and depth) of each habitat. Nine sites affected by anthropogenic influence (fishing and tourism) representing different habitats/substrates were sampled. Underwater surveys were conducted during the warm and cold seasons in 2010 and 2011 at transects that varied in depth according to site. Artificial habitat, followed by coral and rocky habitats, had the highest diversity, evenness, and taxonomic distinctness, while mangrove habitats had the lowest values. This was related to the habitat complexity and possible anthropogenic influences. While the diversity patterns were more strongly related to the type of substrate, followed by the combination of substrate and depth, and the sea temperature had less influence. These findings were related to the ecological traits of the fish communities and their mobility between habitats. Temporal changes in fish community diversity and composition were not detected at all sites, suggesting that these species have high fidelity to their habitats and a high environmental tolerance that allows them to persist in their habitats despite strong changes in sea temperature on the Galapagos archipelago.

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Case Presentation. Distal renal tubular acidosis (dRTA) is characterized by impaired hydrogen ion secretion in the distal nephron resulting either from decreased net activity of the proton pump or from increased luminal membrane hydrogen ion permeability. Typical complications of dRTA include severe hypokalemia, normal anion gap metabolic acidosis, nephrolithiasis, and nephrocalcinosis. The patient is a 25-year-old woman in immediate puerperium with hypokalemia leading to paralysis, and the laboratory findings in this patients were concerning for dRTA. It is rare to encounter this entity during pregnancy, and the impact of this pathology is unknown.

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INTRODUCTION: Urinary tract injuries (UTI) are a frequent complication of morbidly adherent placenta (MAP) management. In this study, we aim to characterize the type of UTI that occurs and to define if their incidence varies after establishing a fixed interdisciplinary group for the protocolized management of patients with MAP. METHODOLOGY: All patients with confirmed MAP attended between 2011 and 2019 in our institution, were included. We analyzed the effect of a change in the surgical protocol including rigid ureteral catheters, vesicouterine dissection before hysterotomy and interdisciplinary planning, in the bladder or ureteral injuries incidence. RESULTS: The study included 65 women. UTI was identified in 27.7% of patients and was associated with a greater volume of blood loss, transfusion requirement, hospital stay, and the need for additional surgeries. There was a high frequency of UTI in patients without protocolized management. The use of rigid ureteral catheters and retrovesical dissection before hysterotomy were associated with a less ureteral injury. CONCLUSIONS: Developing expertise among the members of the surgical team is essential to improve results. Using rigid ureteral catheters, performing retrovesical dissection before hysterotomy, and performing less extensive surgeries in selected patients are associated with a low frequency of ureteral injuries.

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Extreme drought events have negative effects on forest diversity and functioning. At the species level, however, these effects are still unclear, as species vary in their response to drought through specific functional trait combinations. We used long-term demographic records of 21,821 trees and extensive databases of traits to understand the responses of 338 tropical dry forests tree species to ENSO2015 , the driest event in decades in Northern South America. Functional differences between species were related to the hydraulic safety-efficiency trade-off, but unexpectedly, dominant species were characterised by high investment in leaf and wood tissues regardless of their leaf phenological habit. Despite broad functional trait combinations, tree mortality was more widespread in the functional space than tree growth, where less adapted species showed more negative net biomass balances. Our results suggest that if dry conditions increase in this ecosystem, ecological functionality and biomass gain would be reduced.

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