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1.
Am J Transplant ; 21(5): 1825-1837, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33098200

RESUMO

We report the nationwide experience with solid organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients diagnosed with coronavirus disease 2019 (COVID-19) in Spain until 13 July 2020. We compiled information for 778 (423 kidney, 113 HSCT, 110 liver, 69 heart, 54 lung, 8 pancreas, 1 multivisceral) recipients. Median age at diagnosis was 61 years (interquartile range [IQR]: 52-70), and 66% were male. The incidence of COVID-19 in SOT recipients was two-fold higher compared to the Spanish general population. The median interval from transplantation was 59 months (IQR: 18-131). Infection was hospital-acquired in 13% of cases. No donor-derived COVID-19 was suspected. Most patients (89%) were admitted to the hospital. Therapies included hydroxychloroquine (84%), azithromycin (53%), protease inhibitors (37%), and interferon-ß (5%), whereas immunomodulation was based on corticosteroids (41%) and tocilizumab (21%). Adjustment of immunosuppression was performed in 85% of patients. At the time of analysis, complete follow-up was available from 652 patients. Acute respiratory distress syndrome occurred in 35% of patients. Ultimately, 174 (27%) patients died. In univariate analysis, risk factors for death were lung transplantation (odds ratio [OR]: 2.5; 95% CI: 1.4-4.6), age >60 years (OR: 3.7; 95% CI: 2.5-5.5), and hospital-acquired COVID-19 (OR: 3.0; 95% CI: 1.9-4.9).


Assuntos
COVID-19/epidemiologia , Transplante de Células-Tronco Hematopoéticas , Transplante de Órgãos , Transplantados , COVID-19/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Espanha/epidemiologia
2.
Microb Cell Fact ; 18(1): 174, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601204

RESUMO

BACKGROUND: Currently, industrial societies are seeking for green alternatives to conventional chemical synthesis. This demand has merged with the efforts to convert lignocellulosic biomass into value-added products. In this context, xylan, as one of main components of lignocellulose, has emerged as a raw material with high potential for advancing towards a sustainable economy. RESULTS: In this study, the recombinant endoxylanase rXynM from the ascomycete Talaromyces amestolkiae has been heterologously expressed in Pichia pastoris and used as one of the catalysts of an enzyme cascade developed to synthesize the antiproliferative 2-(6-hydroxynaphthyl) ß-D-xylopyranoside, by transglycosylation of 2,6-dihydroxynaphthalene. The approach combines the use of two fungal xylanolytic enzymes, rXynM and the ß-xylosidase rBxTW1 from the same fungus, with the cost-effective substrate xylan. The reaction conditions for the cascade were optimized by a Central Composite Design. Maximal productions of 0.59 and 0.38 g/L were reached using beechwood xylan and birchwood xylan, respectively. For comparison, xylans from other sources were tested in the same reaction, suggesting that a specific optimization is required for each xylan variety. The results obtained using this enzyme cascade and xylan were similar or better to those previously reported for a single catalyst and xylobiose, an expensive sugar donor. CONCLUSIONS: Beechwood and birchwood xylan, two polysaccharides easily available from biomass, were used in a novel enzyme cascade to synthetize an antiproliferative agent. The approach represents a green alternative to the conventional chemical synthesis of 2-(6-hydroxynaphthyl) ß-D-xylopyranoside using a cost-effective substrate. The work highlights the role of xylan as a raw material for producing value-added products and the potential of fungal xylanolytic enzymes in the biomass conversion.


Assuntos
Endo-1,4-beta-Xilanases/biossíntese , Glicosídeos/biossíntese , Talaromyces/enzimologia , Xilanos/metabolismo , Clonagem Molecular , Naftóis , Pichia/genética
3.
Appl Microbiol Biotechnol ; 103(9): 3819-3827, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30887172

RESUMO

Bioengineering of probiotics allows the improvement of their beneficial characteristics. In this work, we develop a molecular tool that would allow the activation of desirable traits in probiotics once they reach the intestine. The activity of upstream regions of bile-inducible genes of Lactobacillus casei BL23 and Lactobacillus plantarum WCFS1 was analyzed using plasmids encoding an anaerobic fluorescent protein as reporter. The promoter P16090 from Lb. casei BL23 was selected and its bile induction confirmed in Lb. casei BL23, Lb. plantarum WCFS1, and in Lactobacillus rhamnosus and Lactobacillus reuteri strains. However, the induction did not occur in Lactococcus lactis MG1363 or Bifidobacterium strains. Studies with different bile compounds revealed the importance of cholic acid in the bile induction process. Induction of fluorescence was also confirmed for transformed Lb. casei BL23 under simulated colonic conditions and in the presence of intestinal microbiota. The developed vector, pNZ:16090-aFP, constitutes a promising tool suitable for the expression of genes of interest under intestinal conditions in probiotic strains of the species Lb. casei, Lb. plantarum, Lb. rhamnosus, and Lb. reuteri.


Assuntos
Bile/metabolismo , Regulação Bacteriana da Expressão Gênica , Lacticaseibacillus casei/genética , Lacticaseibacillus rhamnosus/genética , Lactobacillus plantarum/genética , Humanos , Intestinos/microbiologia , Lacticaseibacillus casei/metabolismo , Lactobacillus plantarum/metabolismo , Lacticaseibacillus rhamnosus/metabolismo , Probióticos/análise , Probióticos/metabolismo , Regiões Promotoras Genéticas
4.
Remote Sens Environ ; 204: 931-941, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32943797

RESUMO

Launched in January 2015, the National Aeronautics and Space Administration (NASA) Soil Moisture Active Passive (SMAP) observatory was designed to provide frequent global mapping of high-resolution soil moisture and freeze-thaw state every two to three days using a radar and a radiometer operating at L-band frequencies. Despite a hardware mishap that rendered the radar inoperable shortly after launch, the radiometer continues to operate nominally, returning more than two years of science data that have helped to improve existing hydrological applications and foster new ones. Beginning in late 2016 the SMAP project launched a suite of new data products with the objective of recovering some high-resolution observation capability loss resulting from the radar malfunction. Among these new data products are the SMAP Enhanced Passive Soil Moisture Product that was released in December 2016, followed by the SMAP/Sentinel-1 Active-Passive Soil Moisture Product in April 2017. This article covers the development and assessment of the SMAP Level 2 Enhanced Passive Soil Moisture Product (L2_SM_P_E). The product distinguishes itself from the current SMAP Level 2 Passive Soil Moisture Product (L2_SM_P) in that the soil moisture retrieval is posted on a 9 km grid instead of a 36 km grid. This is made possible by first applying the Backus-Gilbert optimal interpolation technique to the antenna temperature (TA) data in the original SMAP Level 1B Brightness Temperature Product to take advantage of the overlapped radiometer footprints on orbit. The resulting interpolated TA data then go through various correction/calibration procedures to become the SMAP Level 1C Enhanced Brightness Temperature Product (LiC_TB_E). The LiC_TB_E product, posted on a 9 km grid, is then used as the primary input to the current operational SMAP baseline soil moisture retrieval algorithm to produce L2_SM_P_E as the final output. Images of the new product reveal enhanced visual features that are not apparent in the standard product. Based on in situ data from core validation sites and sparse networks representing different seasons and biomes all over the world, comparisons between L2_SM_P_E and in situ data were performed for the duration of April 1, 2015 - October 30, 2016. It was found that the performance of the enhanced 9 km L2_SM_P_E is equivalent to that of the standard 36 km L2_SM_P, attaining a retrieval uncertainty below 0.040 m3/m3 unbiased root-mean-square error (ubRMSE) and a correlation coefficient above 0.800. This assessment also affirmed that the Single Channel Algorithm using the V-polarized TB channel (SCA-V) delivered the best retrieval performance among the various algorithms implemented for L2_SM_P_E, a result similar to a previous assessment for L2_SM_P.

5.
J Sci Food Agric ; 97(12): 4066-4074, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28397240

RESUMO

BACKGROUND: The phenolic composition of grapes is key when making decisions about harvest date and ensuring the quality of grapes. The present study aimed to investigate the relationship between the detailed phenolic composition of grapes and the agronomic parameters and hyperspectral indices, with the latter being measured via field radiometry techniques. RESULTS: Good correlations were found between phenolic composition (both anthocyanin and flavanol composition) and some hyperspectral indices related to vigor, such as the NDVI (normalized difference vegetation index) and the SAVI (soil adjusted vegetation index). The strongest correlations were observed between the phenolic composition of grape skin at harvest time and variables measured from grapes at veraison time, as well as variables determined from grapevines at harvest time. The potential usefulness of these hyperspectral indices calculated from measurements performed directly on grapes or grapevines for estimating the anthocyanin and flavanol composition of grape skins was indicated by the high coefficients of determination (R2 = 0.7955 and R2 = 0.8594, respectively) as obtained by means of principal component regression. CONCLUSION: According to the results of the present study, hyperspectral indices calculated from measurements performed directly on grapes at veraison time or on grapevines at harvest time may be useful for estimating the anthocyanin and flavanol composition of grape skins. This suggests that field radiometry might provide valuable information for estimating the phenolic composition of grapes, which may prove to be very useful when establishing strategies for harvest planning. © 2017 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Fenóis/química , Extratos Vegetais/química , Vitis/química , Agricultura , Frutas/química , Frutas/crescimento & desenvolvimento , Solo/química , Vitis/crescimento & desenvolvimento
6.
Sci Total Environ ; 846: 157537, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-35872192

RESUMO

Soil moisture (SM) plays a key role in the water cycle, and its variability is intimately linked to coupled land-atmosphere processes. Having a good knowledge of soil-atmospheric interactions is thus essential to assess the impact of climate change on SM; however, many aspects of how water and energy exchanges occur in the soil-atmosphere continuum are still uncertain. In particular, it is known that atmospheric circulation patterns influence climate conditions over Europe but their impact on SM has only rarely been studied. This study provides insight into how atmospheric patterns influence soil moisture dynamics in Europe, where an increase in temperature and agricultural droughts are expected as an impact of climate change. To do so, we analysed the influence of the North Atlantic Oscillation (NAO), the Arctic Oscillation (AO), and the El Niño Southern Oscillation (ENSO) on European SM, including lagged responses, for the period 1991-2020 at a monthly scale. Two methods have been used: a lagged correlation analysis and a more sophisticated causality approach using the PCMCI (PC method combined with the momentary conditional independence (MCI) test). SM series from two different databases were considered: the hydrological model LISFLOOD and the reanalysis dataset ERA5-Land. The results from the correlation analysis showed a significant, predominantly negative relationships of SM with NAO and AO over almost all of Europe and no significant relation with ENSO. With the causality analysis, similar patterns are obtained for NAO and AO; however, the PCMCI analysis revealed clear patterns of ENSO influencing SM with a delayed response of one-to-two months in central and northwest Europe. The results obtained in this work highlight that there are causal relations between the main modes of interannual climate oscillations and SM variations in Europe, underlining the importance of accounting for global atmospheric circulations to study current changes in regional soil water-related processes.


Assuntos
El Niño Oscilação Sul , Solo , Atmosfera , Mudança Climática , Água
7.
Healthcare (Basel) ; 10(12)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36553946

RESUMO

The assessment of posture and asymmetries is common in musculoskeletal clinical practice, and correction is a frequent goal. In this setting, posture and asymmetries are usually interpreted in terms of musculoskeletal issues. This study aimed to evaluate spinal asymmetries in case studies of unilateral nephroptosis. A systematic review was performed using PubMed, CINAHL, Scopus and Web of Science. We included case reports and case series of nephroptotic patients which showed diagnostic imaging that allowed us to assess the presence of spinal asymmetries in the frontal plane. The methodological quality of the selected studies was assessed by using Case Report (CARE) checklist. Nineteen studies were included, with a total number of 78 reported patients (69 women) ranging 22 to 44 years old (mean: 29). Only one patient presented with medial nephroptosis, while the rest presented with caudal migration. Ninety-one percent of the cases affected to the right kidney. All cases but two showed homolateral flank closure (lower rib descent, iliac crest raise and/or homolateral side-bending). The correction of nephroptosis, either by supine position or surgical treatment, removed asymmetries in some cases while other cases improved only partly. Manual therapists must consider visceral implications while assessing body posture. Further, since the most common symptom of nephroptosis is loin pain, and it has been claimed that loin pain is underdiagnosed, manual therapists should consider its potential presence during clinical practice. Finally, being that nephroptosis shares several features with idiopathic lumbar scoliosis (type of patient, postural adaptation), more research is needed regarding any possible relation between them.

8.
Elife ; 92020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32142407

RESUMO

How salamanders accomplish progenitor cell proliferation while faithfully maintaining genomic integrity and regenerative potential remains elusive. Here we found an innate DNA damage response mechanism that is evident during blastema proliferation (early- to late-bud) and studied its role during tissue regeneration by ablating the function of one of its components, Eyes absent 2. In eya2 mutant axolotls, we found that DNA damage signaling through the H2AX histone variant was deregulated, especially within the proliferating progenitors during limb regeneration. Ultimately, cell cycle progression was impaired at the G1/S and G2/M transitions and regeneration rate was reduced. Similar data were acquired using acute pharmacological inhibition of the Eya2 phosphatase activity and the DNA damage checkpoint kinases Chk1 and Chk2 in wild-type axolotls. Together, our data indicate that highly-regenerative animals employ a robust DNA damage response pathway which involves regulation of H2AX phosphorylation via Eya2 to facilitate proper cell cycle progression upon injury.


Assuntos
Ambystoma mexicanum/fisiologia , Extremidades/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Regeneração/fisiologia , Animais , Ciclo Celular/fisiologia , Dano ao DNA , Reparo do DNA/fisiologia , Regulação da Expressão Gênica , Histonas/genética , Histonas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Nucleares/genética , Proteínas Tirosina Fosfatases/genética
9.
Sensors (Basel) ; 8(2): 1174-1197, 2008 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-27879759

RESUMO

The high spatio-temporal variability of soil moisture is the result of atmosphericforcing and redistribution processes related to terrain, soil, and vegetation characteristics.Despite this high variability, many field studies have shown that in the temporal domainsoil moisture measured at specific locations is correlated to the mean soil moisture contentover an area. Since the measurements taken by Synthetic Aperture Radar (SAR)instruments are very sensitive to soil moisture it is hypothesized that the temporally stablesoil moisture patterns are reflected in the radar backscatter measurements. To verify this hypothesis 73 Wide Swath (WS) images have been acquired by the ENVISAT AdvancedSynthetic Aperture Radar (ASAR) over the REMEDHUS soil moisture network located inthe Duero basin, Spain. It is found that a time-invariant linear relationship is well suited forrelating local scale (pixel) and regional scale (50 km) backscatter. The observed linearmodel coefficients can be estimated by considering the scattering properties of the terrainand vegetation and the soil moisture scaling properties. For both linear model coefficients,the relative error between observed and modelled values is less than 5 % and thecoefficient of determination (R²) is 86 %. The results are of relevance for interpreting anddownscaling coarse resolution soil moisture data retrieved from active (METOP ASCAT)and passive (SMOS, AMSR-E) instruments.

10.
NPJ Regen Med ; 2: 30, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29302364

RESUMO

Axolotl salamanders are powerful models for understanding how regeneration of complex body parts can be achieved, whereas mammals are severely limited in this ability. Factors that promote normal axolotl regeneration can be examined in mammals to determine if they exhibit altered activity in this context. Furthermore, factors prohibiting axolotl regeneration can offer key insight into the mechanisms present in regeneration-incompetent species. We sought to determine if we could experimentally compromise the axolotl's ability to regenerate limbs and, if so, discover the molecular changes that might underlie their inability to regenerate. We found that repeated limb amputation severely compromised axolotls' ability to initiate limb regeneration. Using RNA-seq, we observed that a majority of differentially expressed transcripts were hyperactivated in limbs compromised by repeated amputation, suggesting that mis-regulation of these genes antagonizes regeneration. To confirm our findings, we additionally assayed the role of amphiregulin, an EGF-like ligand, which is aberrantly upregulated in compromised animals. During normal limb regeneration, amphiregulin is expressed by the early wound epidermis, and mis-expressing this factor lead to thickened wound epithelium, delayed initiation of regeneration, and severe regenerative defects. Collectively, our results suggest that repeatedly amputated limbs may undergo a persistent wound healing response, which interferes with their ability to initiate the regenerative program. These findings have important implications for human regenerative medicine.

11.
Rev. latinoam. psicol ; Rev. latinoam. psicol;31(3): 491-504, 1999.
Artigo em Espanhol | LILACS | ID: lil-300442

RESUMO

Se revisan los planteamientos mas básicos de los principales paradigmas psicológicos y su impacto sobre el aprendizaje. A partir de un conjunto de referencias y reflexiones sobre la educación superior (particularmente en Venezuela) se discute la necesidad de cambio en la praxis educativa universitaria. Se observan deficiencias en la ejecución actual de los estudiantes universitarios de pregrado, tanto al inicio como al final de sus estudios, deficiencias que el autor atribuye a la prevalencia del modelo asociacionista del aprendizaje. Si bien se considera que existen cambios en el campo teórico-reflexivo orientados por los aportes cognitivos y constructivistas, creemos que falta mucho trabajo y reflexión para llevar estos aportes al aula universitaria. Finalmente en función de lo expuesto, se presentan algunas reflexiones orientadas a un modelo de aula universitaria en el cual se pase del énfasis en los productos al énfasis en los procesos. Esto se considera como un reto para el siglo XXI.


Assuntos
Cognição , Ensino/tendências , Aprendizagem , Universidades
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