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1.
Sci Total Environ ; 782: 146819, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33838377

RESUMO

Wetland ecosystems are critical to the regulation of the global carbon cycle, and there is a high demand for data to improve carbon sequestration and emission models and predictions. Decomposition of plant litter is an important component of ecosystem carbon cycling, yet a lack of knowledge on decay rates in wetlands is an impediment to predicting carbon preservation. Here, we aim to fill this knowledge gap by quantifying the decomposition of standardised green and rooibos tea litter over one year within freshwater and coastal wetland soils across four climates in Australia. We also captured changes in the prokaryotic members of the tea-associated microbiome during this process. Ecosystem type drove differences in tea decay rates and prokaryotic microbiome community composition. Decomposition rates were up to 2-fold higher in mangrove and seagrass soils compared to freshwater wetlands and tidal marshes, in part due to greater leaching-related mass loss. For tidal marshes and freshwater wetlands, the warmer climates had 7-16% less mass remaining compared to temperate climates after a year of decomposition. The prokaryotic microbiome community composition was significantly different between substrate types and sampling times within and across ecosystem types. Microbial indicator analyses suggested putative metabolic pathways common across ecosystems were used to breakdown the tea litter, including increased presence of putative methylotrophs and sulphur oxidisers linked to the introduction of oxygen by root in-growth over the incubation period. Structural equation modelling analyses further highlighted the importance of incubation time on tea decomposition and prokaryotic microbiome community succession, particularly for rooibos tea that experienced a greater proportion of mass loss between three and twelve months compared to green tea. These results provide insights into ecosystem-level attributes that affect both the abiotic and biotic controls of belowground wetland carbon turnover at a continental scale, while also highlighting new decay dynamics for tea litter decomposing under longer incubations.


Assuntos
Microbiota , Áreas Alagadas , Austrália , Carbono , Ecossistema , Água Doce , Solo , Chá
2.
J Agric Food Chem ; 69(13): 3982-3991, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33755449

RESUMO

As important signal metabolites within enterohepatic circulation, bile acids (BAs) play a pivotal role during the occurrence and development of diet-induced nonalcoholic fatty liver disease (NAFLD). Here, we evaluated the functional effects of BAs and gut microbiota contributing to sucralose consumption-induced NAFLD of mice. The results showed that sucralose consumption significantly upregulated the abundance of intestinal genera Bacteroides and Clostridium, which produced deoxycholic acid (DCA) accumulating in multiple biological matrixes including feces, serum, and liver of mice. Subsequently, elevated hepatic DCA, one of the endogenous antagonists of the farnesol X receptor (Fxr), inhibited hepatic gene expression including a small heterodimer partner (Shp) and Fxr leading to sucralose-induced NAFLD in mice. Dietary supplements with fructo-oligosaccharide or metformin markedly restored genera Bacteroides and Clostridium abundance and the DCA level of sucralose-consuming mice, which eventually ameliorated NAFLD. These findings highlighted the effects of gut microbiota and its metabolite DCA on sucralose-induced NAFLD of mice.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Animais , Ácidos e Sais Biliares , Ácido Desoxicólico , Fígado , Camundongos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , Sacarose/análogos & derivados
3.
Ecotoxicol Environ Saf ; 199: 110740, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32446102

RESUMO

Dibutyl phthalate (DBP) is one of the most ubiquitous phthalate esters found in everyday products, and is receiving increased attention as an immunologic adjuvant. However, information regarding DBP-aggravated allergic asthma is still limited. This study used a mouse model sensitized with ovalbumin (OVA) to determine any adverse effects of DBP on allergic asthma. Our results reveal that allergic asthmatic mice exposed to DBP for an extended period had a significant increase in inflammatory cell infiltration; a significant increase in levels of serum immunoglobulin and T helper 2 cell (Th2) and T helper 17 cell (Th17) cytokines in lung tissue; and significant changes in lung histology and AHR, all of which are typical asthmatic symptoms. The levels of oxidative stress and levels of the neuropeptide, calcitonin gene related peptide (CGRP), were also elevated after DBP exposure. Interestingly, blocking oxidative stress by administering melatonin (MT) not only reduced oxidative stress and CGRP levels, but also ameliorated the asthmatic symptoms. Collectively, these results show that DBP exacerbates asthma-like pathologies by increasing the expression of CGRP mediated by oxidative stress.


Assuntos
Asma/induzido quimicamente , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Dibutilftalato/toxicidade , Poluentes Ambientais/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Animais , Asma/imunologia , Asma/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Melatonina/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Células Th2/efeitos dos fármacos , Células Th2/imunologia
4.
Biochem Biophys Res Commun ; 525(4): 863-869, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171522

RESUMO

Evidences suggest that dietary docosahexaenoic acid (DHA) supplementation may have pleiotropic beneficial effects on health. However, the underlying mechanisms and crucial targets that are involved in achieving these benefits remain to be clarified. In this study, we employed biochemical analysis and liquid chromatography-mass spectrometry (LC-MS) based untargeted metabolomics coupled with multivariate statistical analysis to identify potential metabolic targets of DHA in adult rats at 48 h post-feeding. Blood biochemical analysis showed a significant decrease in triglyceride level of DHA diet group, the untargeted metabolomic analysis revealed that some metabolites were significantly different between the DHA diet group and the basal diet group, including fatty acids (16:0, 18:1, 20:5n3, 22:2n6 and 24:0), diglyceride (20:0/18:2n6, 18:3n6/22:6n3, 20:4n3/20:4n3, and 22:0/24:0), PIP2 (18:2/20:3), phytol, lysoSM (d18:1), 12-hydroxyheptadecatrienoic acid, dihydrocorticosterone and N1-acetylspermine, which are mainly involved in fat mobilization and triglyceride hydrolysis, arachidonic acid, steroid hormone, and polyamine metabolism. To our knowledge, this is the first report that links the metabolic effects of DHA with arachidonic acid, steroid, and polyamine metabolism. Our finding suggests that the beneficial effects of DHA, may not directly require its own metabolic derivatives, but could be achieved by metabolic regulation.


Assuntos
Ácido Araquidônico/sangue , Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Docosa-Hexaenoicos/farmacologia , Triglicerídeos/sangue , Animais , Análise Química do Sangue , Cromatografia Líquida , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/sangue , Análise dos Mínimos Quadrados , Espectrometria de Massas/estatística & dados numéricos , Poliaminas/sangue , Ratos , Reprodutibilidade dos Testes
5.
Int J Nanomedicine ; 13: 2447-2462, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29719393

RESUMO

BACKGROUND: Core-shell-structured nanoparticles (NPs) have attracted much scientific attention due to their promising potential in biomedical fields in recent years. However, their underlying mechanisms of action and potential adverse effects following administration remain unknown. METHODS: In the present study, a 1H nuclear magnetic resonance-based metabonomic strategy was applied to investigate the metabolic consequences in rats following the intravenous administration of parent NPs of core-shell-structured nanoparticles, Fe3O4@SiO2-NH2 (Fe@Si) NPs. RESULTS: Alterations reflected in plasma and urinary metabonomes indicated that Fe@Si NPs induced metabolic perturbation in choline, ketone-body, and amino-acid metabolism besides the common metabolic disorders in tricarboxylic acid cycle, lipids, and glycogen metabolism often induced by the exogenous agents. Additionally, intestinal flora metabolism and the urea cycle were also influenced by Fe@Si NP exposure. Time-dependent biological effects revealed obvious metabolic regression, dose-dependent biological effects implied different biochemical mechanisms between low- and high-dose Fe@Si NPs, and size-dependent biological effects provided potential windows for size optimization. CONCLUSION: Nuclear magnetic resonance-based metabonomic analysis helps in understanding the biological mechanisms of Fe@Si NPs, provides an identifiable ground for the selection of view windows, and further serves the clinical translation of Fe@Si NP-derived and -modified bioprobes or bioagents.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Nanopartículas de Magnetita/administração & dosagem , Nanopartículas de Magnetita/química , Metabolômica/métodos , Administração Intravenosa , Aminas/química , Aminoácidos/metabolismo , Animais , Colina/metabolismo , Relação Dose-Resposta a Droga , Microbioma Gastrointestinal/efeitos dos fármacos , Glicogênio/metabolismo , Nanopartículas de Magnetita/efeitos adversos , Masculino , Nanoconchas/efeitos adversos , Nanoconchas/química , Plasma/efeitos dos fármacos , Plasma/metabolismo , Ratos Sprague-Dawley , Dióxido de Silício/química
6.
Biomaterials ; 151: 66-77, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29078200

RESUMO

Restoration of tissue integrity and tissue function of wounded skin are both essential for wound repair and regeneration, while synergistic promotion of the two remains elusive. Since elevated reactive oxygen species (ROS) production in the injured site has been implicated in triggering a set of deleterious effects such as cellular senescence, fibrotic scarring, and inflammation, it is speculated that alleviating oxidative stress in the microenvironment of injured site would be beneficial to promote regenerative wound healing. In this study, a highly versatile ROS-scavenging tissue adhesive nanocomposite is synthesized by immobilizing ultrasmall ceria nanocrystals onto the surface of uniform mesoporous silica nanoparticles (MSN). The ceria nanocrystals decorated MSN (MSN-Ceria) not only has strong tissue adhesion strength, but also significantly restricts ROS exacerbation mediated deleterious effects, which efficiently accelerates the wound healing process, and more importantly, the wound area exhibits an unexpected regenerative healing characteristic featured by marked skin appendage morphogenesis and limited scar formation. This strategy can also be adapted to other wound repair where both ROS-scavenging activity and tissue adhesive ability matter.


Assuntos
Cério/química , Nanopartículas Metálicas/química , Espécies Reativas de Oxigênio/metabolismo , Dióxido de Silício/química , Adesivos Teciduais/química , Cicatrização/efeitos dos fármacos , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cicatriz/metabolismo , DNA Complementar/metabolismo , Humanos , Inflamação/terapia , Masculino , Tamanho da Partícula , Porosidade , Ratos , Ratos Sprague-Dawley , Pele/efeitos dos fármacos , Propriedades de Superfície , Aderências Teciduais , Adesivos Teciduais/farmacologia
7.
Complement Ther Clin Pract ; 28: 152-160, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28779923

RESUMO

OBJECTIVE: Cupping therapy is widely used in East Asia, the Middle East, or Central and North Europe to manage the symptom of knee osteoarthritis (KOA). The purpose of this systematic review was to evaluate the available evidence from randomized controlled trials (RCTs) of cupping therapy for treating patients with KOA. METHODS: The following databases were searched from their inception until January 2017: PubMed, Embase, the Cochrane Central Register of Controlled Trials and four Chinese databases [WanFang Med Database, Chinese BioMedical Database, Chinese WeiPu Database, and China National Knowledge Infrastructure (CNKI)]. Only the RCTs related to the effects of cupping therapy on KOA were included in this systematic review. A quantitative synthesis of RCTs will be conducted using RevMan 5.3 software. Study selection, data extraction, and validation was performed independently by two reviewers. Cochrane criteria for risk-of-bias were used to assess the methodological quality of the trials. RESULTS: Seven RCTs met the inclusion criteria, and most were of low methodological quality. Study participants in the dry cupping therapy plus the Western medicine therapy group showed significantly greater improvements in the pain [MD = -1.01, 95%CI (-1.61, -0.41), p < 0.01], stiffness [MD = -0.81, 95%CI (-1.14, -0.48), p < 0.01] and physical function [MD = -5.53, 95%CI (-8.58, -2.47), p < 0.01] domains of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) compared to participants in the Western medicine therapy group, with low heterogeneity (Chi2 = 0.00 p = 1.00, I2 = 0% in pain; Chi2 = 0.45 p = 0.50, I2 = 0% in stiffness; Chi2 = 1.09 p = 0.30, I2 = 9% in physical function). However, it failed to do so on a Visual Analog Scale (VAS) [MD = -0.32, 95%CI (-0.70, 0.05), p = 0.09]. In addition, when compared with Western medicine therapy alone, meta-analysis of four RCTs suggested favorable statistically significant effects of wet cupping therapy plus western medicine on response rate [MD = 1.06, 95%CI (1.01, 1.12), p = 0.03; heterogeneity: Chi2 = 1.13, p = 0.77, I2 = 0%] and Lequesne Algofunctional Index (LAI) [MD = -2.74, 95%CI (-3.41, -2.07), p < 0.01; heterogeneity: Chi2 = 2.03, p = 0.57, I2 = 0% ]. CONCLUSION: Only weak evidence can support the hypothesis that cupping therapy can effectively improve the treatment efficacy and physical function in patients with KOA.


Assuntos
Manipulações Musculoesqueléticas , Osteoartrite do Joelho/terapia , Adulto , Humanos , Dor , Medição da Dor , Amplitude de Movimento Articular , Resultado do Tratamento
8.
PLoS One ; 11(6): e0156254, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27281327

RESUMO

The oomycete Phytophthora infestans causes late blight of potato, which can completely destroy the crop. Therefore, for the past 160 years, late blight has been the most important potato disease worldwide. The identification of cultivars with high and durable field resistance to P. infestans is an objective of most potato breeding programs. This type of resistance is polygenic and therefore quantitative. Its evaluation requires multi-year and location trials. Furthermore, quantitative resistance to late blight correlates with late plant maturity, a negative agricultural trait. Knowledge of the molecular genetic basis of quantitative resistance to late blight not compromised by late maturity is very limited. It is however essential for developing diagnostic DNA markers that facilitate the efficient combination of superior resistance alleles in improved cultivars. We used association genetics in a population of 184 tetraploid potato cultivars in order to identify single nucleotide polymorphisms (SNPs) that are associated with maturity corrected resistance (MCR) to late blight. The population was genotyped for almost 9000 SNPs from three different sources. The first source was candidate genes specifically selected for their function in the jasmonate pathway. The second source was novel candidate genes selected based on comparative transcript profiling (RNA-Seq) of groups of genotypes with contrasting levels of quantitative resistance to P. infestans. The third source was the first generation 8.3k SolCAP SNP genotyping array available in potato for genome wide association studies (GWAS). Twenty seven SNPs from all three sources showed robust association with MCR. Some of those were located in genes that are strong candidates for directly controlling quantitative resistance, based on functional annotation. Most important were: a lipoxygenase (jasmonate pathway), a 3-hydroxy-3-methylglutaryl coenzyme A reductase (mevalonate pathway), a P450 protein (terpene biosynthesis), a transcription factor and a homolog of a major gene for resistance to P. infestans from the wild potato species Solanum venturii. The candidate gene approach and GWAS complemented each other as they identified different genes. The results of this study provide new insight in the molecular genetic basis of quantitative resistance in potato and a toolbox of diagnostic SNP markers for breeding applications.


Assuntos
Oomicetos/patogenicidade , Phytophthora infestans/genética , Doenças das Plantas/parasitologia , Proteínas de Plantas/genética , Polimorfismo de Nucleotídeo Único/genética , Solanum tuberosum/genética , Solanum tuberosum/parasitologia , Mapeamento Cromossômico , Ligação Genética , Genótipo , Imunidade Inata/genética , Fenótipo , Phytophthora infestans/parasitologia , Doenças das Plantas/genética , Locos de Características Quantitativas
9.
J Food Prot ; 78(12): 2220-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26613917

RESUMO

Bacteriophages (phages) have been used for biocontrol of Escherichia coli O157 and other pathogenic bacteria in many different matrices and foods, but few studies have included inactivation of residual phages in culture medium before plating and enumeration of surviving host bacteria for the assessment of phage efficacy. This oversight may lead to overestimation of phage efficacy. The ability of virucidal solution containing a mixture of ferrous sulfate [iron(II) sulfate, FeSO4] and tea extract [Fe(II)T] to inactivate residual T5-like, T1-like, T4-like, and rV5-like phages was assessed using E. coli O157 as the host. At concentrations of ≥10 mM FeSO4, all phages were not detected after 20 min in a broth culture model. Compared with the virucidal solution-free samples (1 to 96% recovery), Fe(II)T (10 mM FeSO4 plus 15% tea extract) recovered a greater (P < 0.01) number of E. coli O157 from phage-treated broth culture (97 to 100% recovery) and beef samples (52 to 100% recovery). Moreover, with the addition of Fe(II)T, the number of bacteria surviving after exposure to T5-like or T4-like phages was greater (P < 0.01) than that after exposure to T1-like or rV5-like phages. Consequently, use of a virucide for phage inactivation is recommended to improve the accuracy of evaluations of phage efficacy for biocontrol of E. coli O157.


Assuntos
Colífagos/efeitos dos fármacos , Escherichia coli O157/virologia , Compostos Ferrosos/química , Chá/química , Animais , Antibacterianos/química , Antivirais/química , Bovinos , Farmacorresistência Bacteriana , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Microbiologia de Alimentos , Carne/microbiologia , Reprodutibilidade dos Testes
10.
BMC Genomics ; 12: 484, 2011 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-21970685

RESUMO

BACKGROUND: Characterization of population structure and genetic diversity of germplasm is essential for the efficient organization and utilization of breeding material. The objectives of this study were to (i) explore the patterns of population structure in the pollen parent heterotic pool using different methods, (ii) investigate the genome-wide distribution of genetic diversity, and (iii) assess the extent and genome-wide distribution of linkage disequilibrium (LD) in elite sugar beet germplasm. RESULTS: A total of 264 and 238 inbred lines from the yield type and sugar type inbreds of the pollen parent heterotic gene pools, respectively, which had been genotyped with 328 SNP markers, were used in this study. Two distinct subgroups were detected based on different statistical methods within the elite sugar beet germplasm set, which was in accordance with its breeding history. MCLUST based on principal components, principal coordinates, or lapvectors had high correspondence with the germplasm type information as well as the assignment by STRUCTURE, which indicated that these methods might be alternatives to STRUCTURE for population structure analysis. Gene diversity and modified Roger's distance between the examined germplasm types varied considerably across the genome, which might be due to artificial selection. This observation indicates that population genetic approaches could be used to identify candidate genes for the traits under selection. Due to the fact that r2 >0.8 is required to detect marker-phenotype association explaining less than 1% of the phenotypic variance, our observation of a low proportion of SNP loci pairs showing such levels of LD suggests that the number of markers has to be dramatically increased for powerful genome-wide association mapping. CONCLUSIONS: We provided a genome-wide distribution map of genetic diversity and linkage disequilibrium for the elite sugar beet germplasm, which is useful for the application of genome-wide association mapping in sugar beet as well as the efficient organization of germplasm.


Assuntos
Beta vulgaris/genética , Variação Genética , Desequilíbrio de Ligação , Loci Gênicos , Genoma de Planta , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Análise de Componente Principal
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