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1.
Environ Monit Assess ; 196(2): 152, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38225435

RESUMO

Preserving lacustrine ecosystems is vital for sustainable watershed development, and forecasting the environmental water availability of lakes would support policymakers in developing sound management strategies. This study proposed a methodology that merges the lake water level prediction and environmental water availability evaluation. The temporal fusion transformer (TFT) model forecasted the lake water levels for the next 7 days by inputting the streamflow and lake water level data for the past 30 days. The environmental water availability was assessed by comparing the forecasted lake water levels with the environmental water requirements, resulting in adequate, regular, scarce, and severely scarce environmental water availability. The methodology was tested in two case studies: Poyang Lake and Dongting Lake, the two largest freshwater lakes in the Yangtze River Basin, China. The TFT model performed well in forecasting the lake water levels, as shown by the high coefficient of determination and finite root mean square error. The coefficients of determination exceeded 0.98 during the model training, validation, and test for both Poyang Lake and Dongting Lake, and the root mean square errors ranged from 0.06 to 0.46 m. The accurate prediction of lake water level promoted the precise forecasting of the environmental water availability with the high Kappa coefficient exceeding 0.90. Results indicated the rationality and effectiveness of integrating the lake water level prediction and environmental water availability evaluation. Future research includes the applicability of the TFT model to other lakes worldwide to test the proposed approach and investigate strategies to cope with environmental water scarcity.


Assuntos
Ecossistema , Lagos , Água , Monitoramento Ambiental/métodos , China
2.
Clin Infect Dis ; 69(5): 861-864, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-30715242

RESUMO

Using metagenomics analysis, we are the first to identify the presence of a small, circular, single-stranded Gemykibivirus (GkV) genome from the respiratory tract of an elderly woman with severe acute respiratory distress syndrome. Our results suggest that further studies on whether GkVs infect humans and cause respiratory disease are needed.


Assuntos
Infecções por Vírus de DNA/diagnóstico , Vírus de DNA/isolamento & purificação , Genoma Viral , Síndrome do Desconforto Respiratório/virologia , Doença Aguda , Fatores Etários , Idoso , Brônquios/virologia , Infecções por Vírus de DNA/virologia , Vírus de DNA/genética , Humanos , Metagenômica , Sequenciamento Completo do Genoma
4.
Int J Mol Sci ; 19(8)2018 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-30096912

RESUMO

Variations in substrate chemistry and the micro-structure were shown to have a significant effect on the biology of human mesenchymal stromal cells (hMSCs). This occurs when differences in the surface properties indirectly modulate pathways within numerous signaling networks that control cell fate. To understand how the surface features affect hMSC gene expression, we performed RNA-sequencing analysis of bone marrow-derived hMSCs cultured on tissue culture-treated polystyrene (TCP) and poly(l-lactide) (PLLA) based substrates of differing topography (Fl: flat and Fs: fibrous) and chemistry (Pr: pristine and Am: aminated). Whilst 80% of gene expression remained similar for cells cultured on test substrates, the analysis of differentially expressed genes (DEGs) revealed that surface topography significantly altered gene expression more than surface chemistry. The Fl and Fs topologies introduced opposite directional alternations in gene expression when compared to TCP control. In addition, the effect of chemical treatment interacted with that of topography in a synergistic manner with the Pr samples promoting more DEGs than Am samples in all gene ontology function groups. These findings not only highlight the significance of the culture surface on regulating the overall gene expression profile but also provide novel insights into cell-material interactions that could help further design the next-generation biomaterials to facilitate hMSC applications. At the same time, further studies are required to investigate whether or not the observations noted correlate with subsequent protein expression and functionality of cells.


Assuntos
Diferenciação Celular/genética , Proliferação de Células/genética , Células-Tronco Mesenquimais/citologia , Osteogênese/genética , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Células Cultivadas , Regulação da Expressão Gênica no Desenvolvimento/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Células-Tronco Mesenquimais/metabolismo , Osteogênese/efeitos dos fármacos
5.
Water Res ; 262: 122118, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39083901

RESUMO

Catchment-scale nitrate dynamics involve complex coupling of hydrological transport and biogeochemical transformations, imposing challenges for source control of diffuse pollution. The Damköhler number (Da) offers a dimensionless dual-lens concept that integrates the timescales of exposure and processing, but quantifying both timescales in heterogeneous catchments remains methodologically challenging. Here, we propose a novel spatio-temporal framework for catchment-scale quantification of Da based on the ecohydrological modeling platform EcH2O-iso that coupled isotope-aided water age tracking and nitrate modeling. We examined Da variability of soil denitrification in the heterogeneous Selke catchment (456 km2, central Germany). Results showed that warm-season soil denitrification was of catchment-wide significance (Da >1), while its high spatial variations were co-determined by varying exposure times and removal efficiencies (e.g., channel-connected lowland areas are hotspots). Moreover, Da seasonally shifted from processing-dominance to transport-dominance during the wet-spring season (from >1 to <1), implying important linkages between summer terrestrial denitrification and subsequent winter river water quality. Under the prolonged 2018-2019 droughts, denitrification removal generally reduced, resulting in further accumulation in agricultural soils. Moreover, the space-time responses of Da variability indicated important implications for catchment water quality. The older water in lowland areas exhibited extra risks of groundwater contamination, whilst agricultural areas in the hydrologically responsive uplands became sensitive hotspots for export and river water pollution. Importantly, the lowland pixels intersecting river channels exhibited high removal efficiencies, as well as high resilience to the disturbances (wet-spring Da shifted to >1 under drought conditions). The proposed catchment-wide Da framework is implied by mechanistic modeling, which is transferable across various environmental conditions. This could shed light on understanding of catchment N processes, and thus providing site-specific implications of non-point source pollution controls.


Assuntos
Nitratos , Qualidade da Água , Nitratos/análise , Monitoramento Ambiental/métodos , Desnitrificação , Estações do Ano , Modelos Teóricos , Poluentes Químicos da Água/análise , Solo/química , Alemanha , Rios/química
6.
Front Mol Biosci ; 11: 1366753, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38486946

RESUMO

Introduction: Maintenance hemodialysis is an effective treatment for end-stage renal disease patients. A critical factor contributing to the deterioration and death of maintenance hemodialysis patients is inflammation. Therefore, we focused on two inflammatory markers, serum ferritin and neutrophil-to-lymphocyte ratio, to speculate whether they could predict the prognosis of maintenance hemodialysis patients. Patients and methods: We followed 168 patients with maintenance hemodialysis from July 2019 to July 2022 with the endpoint of all-cause death or follow-up completion. Receiver operating characteristic curves were plotted to assess the values of serum ferritin, neutrophil-to-lymphocyte ratio and serum ferritin combined with neutrophil-to-lymphocyte ratio to predict the outcomes of maintenance hemodialysis patients. Kaplan-Meier survival curves were constructed to compare survival rates over time. Results: Receiver operating characteristic curves demonstrated that the best cut-off value of serum ferritin for predicting the prognosis of maintenance hemodialysis patients was 346.05 µg/L, and that of neutrophil-to-lymphocyte ratio was 3.225. Furthermore, a combination of both had a more excellent predicting value than either index (p < 0.05). Kaplan-Meier survival curve analyses revealed that low serum ferritin levels and low neutrophil-to-lymphocyte ratio had a higher probability of survival than high ferritin levels and high neutrophil-to-lymphocyte ratio, separately. Conclusion: Elevated serum ferritin and neutrophil-to-lymphocyte ratio are closely related to all-cause mortality among maintenance hemodialysis patients, for which they may be predictors of all-cause mortality. Additionally, the combination of the two has a much higher predictor value for the prognosis of maintenance hemodialysis patients.

7.
Int J Syst Evol Microbiol ; 63(Pt 8): 2794-2799, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23315406

RESUMO

Our previous published data indicated that the two rhizobial strains SCAU7(T) and SCAU27, which were isolated from the root nodules of Astragalus luteolus and Astragalus ernestii respectively, in Sichuan Province, China, might be novel species of the genus Mesorhizobium. Their exact taxonomic position was determined in the present study by using polyphasic approaches. Comparative analysis of nearly full-length 16S rRNA gene sequences showed that these strains belonged to the genus Mesorhizobium, with Mesorhizobium ciceri USDA 3383(T), Mesorhizobium loti NZP 2213(T), Mesorhizobium shangrilense CCBAU 65327(T) and Mesorhizobium australicum WSM2073(T) as the closest neighbours (>99 % 16S rRNA gene sequence similarity). Phylogenies of the housekeeping genes atpD and recA confirmed their distinct position, showing low similarity with respect to those of M. loti LMG 6125(T) (96.5 % and 92.3 % similarity respectively), M. ciceri USDA 3383(T) (96.8 % and 93.3 % similarity, respectively), M. shangrilense CCBAU 65327(T) (96.5 % and 92.7 % similarity, respectively) and M. australicum WSM2073(T) (95.4 % and 90.6 % similarity, respectively). The DNA-DNA relatedness values between strain SCAU7(T) and strain SCAU27 were 83.0 %, showing that they belong to the same species. The DNA-DNA relatedness values of SCAU7(T) with M. loti NZP 2213(T), M. ciceri USDA 3383(T) and M. shangrilense CCBAU 65327(T) were 41.1 %, 48.8 % and 23.4 %, respectively, clearly indicating that strain SCAU7(T) represents a novel species. A series of phenotypic and genotypic tests and comparison of cellular fatty acids indicated that the novel group of isolates was distinct from previously described species. Therefore, we propose that strains SCAU7(T) and SCAU27 represent a novel species of the genus Mesorhizobium, Mesorhizobium sangaii sp. nov., with strain SCAU7(T) (= HAMBI 3318(T) = ACCC 13218(T)) as the type strain.


Assuntos
Astrágalo/microbiologia , Mesorhizobium/classificação , Nódulos Radiculares de Plantas/microbiologia , Técnicas de Tipagem Bacteriana , China , DNA Bacteriano/genética , Ácidos Graxos/análise , Genes Bacterianos , Mesorhizobium/genética , Mesorhizobium/isolamento & purificação , Dados de Sequência Molecular , Fixação de Nitrogênio , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Simbiose
8.
J Dent ; 138: 104733, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37783373

RESUMO

OBJECTIVE: To investigate the cross-linking and protective effect of artemisinin (ART), dihydroartemisinin (DHA), and artesunate (AST) on collagen fibers of demineralized dentin surface. METHODS: Molecular docking was used to predict potential interactions of ART, DHA, and AST with dentin type I collagen. Human third molars without caries were completely demineralized and treated with different solutions for 1 min. The molecular interactions and cross-linking degree of ART and its derivatives with dentin collagen were evaluated by FTIR spectroscopy, total extractable protein content, and a ninhydrin assay. Scanning electron microscopy, hydroxyproline release, and ultimate microtensile strength tests (µUTS) were employed to confirm the mechanical properties and anti-collagenase degradation properties of dentin collagen fibers. RESULTS: ART, DHA, and AST combined with dentin type I collagen mainly through hydrogen bonding and hydrophobic interactions, and the cross-linking reaction sites were mainly C=O and CN functional groups. Compared to the control group, ART and its derivatives significantly increased the degree of cross-linking. Additionally, significant increases were observed in resistance to enzymatic digestion and mechanical properties of the artemisinin and its derivatives group. CONCLUSION: ART, DHA, and AST could cross-link with demineralized dentin collagen, through improving the mechanical properties and anti-collagenase degradation properties. CLINICAL SIGNIFICANCE: The study endorses the potential use of ART and its derivatives as a prospective collagen cross-linking agent for degradation-resistant and long-period dentin bonding in composite resin restorations.


Assuntos
Artemisininas , Colagem Dentária , Humanos , Colágeno Tipo I , Reagentes de Ligações Cruzadas/farmacologia , Reagentes de Ligações Cruzadas/análise , Reagentes de Ligações Cruzadas/química , Simulação de Acoplamento Molecular , Estudos Prospectivos , Resistência à Tração , Colágeno/farmacologia , Colágeno/química , Colagenases/análise , Colagenases/farmacologia , Artemisininas/farmacologia , Artemisininas/análise , Dentina , Colagem Dentária/métodos , Adesivos Dentinários/farmacologia , Adesivos Dentinários/química
9.
Water Res ; 243: 120347, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37490830

RESUMO

High-frequency nitrate-N (NO3--N) data are increasingly available, while accurate assessments of in-stream NO3--N retention in large streams and rivers require a better capture of complex river hydrodynamic conditions. This study demonstrates a fusion framework between high-frequency water quality data and hydrological transport models, that (1) captures river hydraulics and their impacts on solute signal propagation through river hydrodynamic modeling, and (2) infers in-stream retention as the differences between conservatively traced and reactively observed NO3--N signals. Using this framework, continuous 15-min estimates of NO3--N retention were derived in a 6th-order reach of the lower Bode River (27.4 km, central Germany), using long-term sensor monitoring data during a period of normal flow from 2015 to 2017 and a period of drought from 2018 to 2020. The unique NO3--N retention estimates, together with metabolic characteristics, revealed insightful seasonal patterns (from high net autotrophic removal in late-spring to lower rates, to net heterotrophic release during autumn) and drought-induced variations of those patterns (reduced levels of net removal and autotrophic nitrate removal largely buffered by heterotrophic release processes, including organic matter mineralization). Four clusters of diel removal patterns were identified, potentially representing changes in dominant NO3--N retention processes according to seasonal and hydrological conditions. For example, dominance of autotrophic NO3--N retention extended more widely across seasons during the drought years. Such cross-scale patterns and changes under droughts are likely co-determined by catchment and river environments (e.g., river primary production, dissolved organic carbon availability and its quality), which resulted in more complex responses to the sequential droughts. Inferences derived from this novel data-model fusion provide new insights into NO3- dynamics and ecosystem function of large streams, as well as their responses to climate variability. Moreover, this framework can be flexibly transferred across sites and scales, thereby complementing high-frequency monitoring to identify in-stream retention processes and to inform river management.


Assuntos
Nitratos , Rios , Secas , Estações do Ano , Ecossistema , Monitoramento Ambiental/métodos
10.
Nat Commun ; 14(1): 202, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36639378

RESUMO

Eukaryotic messenger RNA (mRNA) typically contains a methylated guanosine (m7G) cap, which mediates major steps of mRNA metabolism. Recently, some RNAs in both prokaryotic and eukaryotic organisms have been found to carry a non-canonical cap such as the NAD cap. Here we report that Arabidopsis DXO family protein AtDXO1, which was previously known to be a decapping enzyme for NAD-capped RNAs (NAD-RNA), is an essential component for m7G capping. AtDXO1 associates with and activates RNA guanosine-7 methyltransferase (AtRNMT1) to catalyze conversion of the guanosine cap to the m7G cap. AtRNMT1 is an essential gene. Partial loss-of-function mutations of AtRNMT1 and knockout mutation of AtDXO1 reduce m7G-capped mRNA but increase G-capped mRNAs, leading to similar pleiotropic phenotypes, whereas overexpression of AtRNMT1 partially restores the atdxo1 phenotypes. This work reveals an important mechanism in m7G capping in plants by which the NAD-RNA decapping enzyme AtDXO1 is required for efficient guanosine cap methylation.


Assuntos
Arabidopsis , Capuzes de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Capuzes de RNA/genética , Capuzes de RNA/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Guanosina/metabolismo , NAD/metabolismo
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