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1.
Plant Dis ; 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340554

RESUMO

Fusarium wilt of banana (Musa spp.), caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense (Foc), is a major constraint to banana production worldwide (Dita et al., 2018). A strain of Foc that affects Cavendish (AAA) bananas in the tropics, called Foc tropical race 4 (TR4; VCG 01213), is of particular concern. Foc TR4 was first detected in Malaysia and Indonesia around 1990 but was restricted to Southeast Asia and northern Australia until 2012. The fungus has since been reported from Africa, the Indian subcontinent, and the Middle East (Viljoen et al., 2020). Foc TR4 was detected in Colombia in 2019 and in Perú in 2021 (Reyes-Herrera et al., 2020). The incursions into Latin America and the Caribbean (LAC) triggered global concerns, as 75% of international export bananas are produced in the region. Banana production in Venezuela, however, is primarily intended for domestic consumption (Aular and Casares, 2011). In 2021 the country produced 533,190 metric tons of banana on an area of 35,896 ha, with an approximate yield of 14,853 kg/ha (FAOSTAT, 2023). In July 2022, severe leaf-yellowing, and wilting, along with internal vascular discoloration of the pseudostem, were noted in Cavendish banana plants cultivar 'Valery' in the states of Aragua (10°11'8″N; 67°34'51″W), Carabobo (10º14'24″N; 67º48'51″W), and Cojedes (9°37'44″N; 68°55'4″W). Necrotic strands from the pseudostems of diseased plants were collected for identification of the causal agent using DNA-based techniques, vegetative compatibility group (VCG) analysis and pathogenicity testing. The samples were first surface disinfected and plated onto potato dextrose agar medium. Single-spored isolates were identified as F. oxysporum based on cultural and morphological characteristics, including white colonies with purple centres, infrequent macroconidia, abundant microconidia on short monophialides, and terminal or intercalary chlamydospores (Leslie and Summerell, 2006). Foc TR4 was identified from five isolates by endpoint and quantitative-PCR using four different primer sets (Li et al. 2013; Dita et al. 2010; Aguayo et al. 2017; Matthews et al. 2020). The same isolates were identified as VCG 01213 by successfully pairing nitrate non-utilizing (nit-1) mutants of the unknown strains with Nit-M testers of Foc TR4 available at Stellenbosch University (Leslie and Summerell, 2006). For pathogenicity testing, 3-month-old Cavendish banana plants cultivar 'Williams' were inoculated with isolates from Venezuela grown on sterile millet seed (Viljoen et al., 2017). Plants developed typical Fusarium wilt symptoms 60 days after inoculation, including yellowing of leaves that progressed from the older to the younger leaves, wilting, and internal discoloration of the pseudostem. Koch's postulates were fulfilled by reisolating and identifying Foc TR4 from the plants by qPCR (Matthews et al., 2020). These results provide scientific proof of the presence of Foc TR4 in Venezuela. The Venezuelan Plant Protection Organization (INSAI) has declared Foc TR4 as a newly introduced pest (January 19, 2023), and infested banana fields were placed under quarantine. Comprehensive surveys are now conducted in all production areas in Venezuela to assess the presence and impact of Foc TR4, and information campaigns were started to make farmers aware of biosecurity protocols. Collaborative initiatives and coordinated actions among all stakeholders are needed to prevent the spread of Foc TR4 to other countries in Latin America, and to develop Foc TR4-resistant bananas (Figueiredo et al. 2023).

3.
Plants (Basel) ; 12(3)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36771611

RESUMO

(1) Background: Maintaining soil fertility and crop productivity using natural microbial diversity could be a feasible approach for achieving sustainable development in agriculture. In this study, we compared soils from vineyards under organic and conventional management by predicting functional profiles through metagenomic analysis based on the 16S rRNA gene. (2) Methods: The structure, diversity and predictive functions of soil bacteria related to the biogeochemical cycle of the soil were analyzed, including oxidative and hydrolytic C-cycling enzymes, N-cycling enzymes and P-cycling enzymes. The inter-row spontaneous vegetation in the organic vineyards was also characterized. (3) Results: A clear effect of the farming system (organic vs. conventional) and cover management (herbicides plus tillage, mowing only and mowing plus tillage) on bacterial beta diversity and predicted functions was evidenced. While conventional viticulture increased the potential capacity of the soil to regulate the cycling of inorganic forms of N, organic viticulture in general enhanced those functions involving organic N, P and C substrates. Although the soil bacterial community responded differently to contrasting soil management strategies, nutrient cycling and carbon sequestration functions remained preserved, suggesting a high bacterial functional redundancy in the soil in any case. However, most of the predicted bacterial functions related to soil organic matter turnover were enhanced by organic management. (4) Conclusions: We posit the potential for organic viticulture to adequately address climate change adaptation in the context of sustainable agriculture.

4.
Plants (Basel) ; 11(23)2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36501295

RESUMO

Habitat manipulation through the promotion of semi-natural habitats such as cover and patch vegetation is a possible means of offsetting the negative impacts of the agricultural practices. A baseline situation is crucial before any successful habitat manipulation is attempted. We studied the effects that current vegetation cover management practices have on plant composition and the potential attraction that the plant families from the semi-natural habitats could have on the Chrysopidae community, a key pest control agent, in five olive farms in Granada (Spain). Vegetation cover was assessed using a point quadrat methodology in eight transects per farm. In addition, the patch vegetation was characterized with 60 transects using a line intercept methodology. The woody patch vegetation and olive tree canopies were vacuumed using a field aspirator to collect adult Chrysopidae. In the cover vegetation we observed great variability in both the richness and diversity of plant communities caused by the vegetation cover management techniques and the transect position (in the middle of the rows or beneath the tree canopy). The plant families with the greatest plant cover were the Asteraceae and Fabaceae, where Asteraceae was favoured by tillage and Fabaceae by grazing, while in the patch vegetation, the predominant families were the Rosaceae and Fagaceae. Our results indicate that the genus Chrysoperla was mostly correlated with the Plantaginaceae, Brassicaceae and Asteraceae plant families in the cover vegetation, and with the Caryophyllaceae and Rosaceae families in the patch vegetation. The genera Apertochrysa and Pseudomallada were associated with the families Malvaceae and Poaceae in the cover vegetation, and with the families Cupressaceae, Poaceae and Pinaceae in the patch vegetation. Our study shows to the farmers the possibilities of vegetation cover management to select plant families for the cover vegetation.

5.
Front Cell Dev Biol ; 10: 791667, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35281092

RESUMO

Obesity is a significant health concern that has reached alarming proportions worldwide. The overconsumption of high-energy foods may cause metabolic dysfunction and promote the generation of new adipocytes by contributing to several obesity-related diseases. Such concerns demand a deeper understanding of the origin of adipocytes if we want to develop new therapeutic approaches. Recent findings indicate that adipocyte development is facilitated by tight epigenetic reprogramming, which is required to activate the gene program to change the fate of mesenchymal stem cells (MSCs) into mature adipocytes. Like adipose tissue, different tissues are also potential sources of adipocyte-generating MSCs, so it is interesting to explore whether the epigenetic mechanisms of adipogenic differentiation vary from one depot to another. To investigate how DNA methylation (an epigenetic mark that plays an essential role in controlling transcription and cellular differentiation) contributes to adipogenic potential, dental pulp stem cells (DPSCs) and periodontal ligament stem cells (PLSCs) were analyzed during adipogenic differentiation in vitro. Here, we show that the capacity to differentiate from DPSCs or PLSCs to adipocytes may be associated with the expression pattern of DNA methylation-related genes acquired during the induction of the adipogenic program. Our study provides insights into the details of DNA methylation during the adipogenic determination of dental stem cells, which can be a starting point to identify the factors that affect the differentiation of these cells and provide new strategies to regulate differentiation and adipocyte expansion.

6.
Life Sci Alliance ; 5(4)2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983823

RESUMO

Carcinogenic insult, such as UV light exposure, creates DNA lesions that evolve into mutations if left unrepaired. These resulting mutations can contribute to carcinogenesis and drive malignant phenotypes. Susceptibility to carcinogens (i.e., the propensity to form a carcinogen-induced DNA lesion) is regulated by both genetic and epigenetic factors. Importantly, carcinogen susceptibility is a critical contributor to cancer mutagenesis. It is known that mutations can be prevented by tumor suppressor regulation of DNA damage response pathways; however, their roles carcinogen susceptibility have not yet been reported. In this study, we reveal that the retinoblastoma (RB1) tumor suppressor regulates UV susceptibility across broad regions of the genome. In particular, centromere and telomere-proximal regions exhibit significant increases in UV lesion susceptibility when RB1 is deleted. Several cancer-related genes are located within genomic regions of increased susceptibility, including telomerase reverse transcriptase, TERT, thereby accelerating mutagenic potential in cancers with RB1 pathway alterations. These findings reveal novel genome stability mechanisms of a tumor suppressor and uncover new pathways to accumulate mutations during cancer evolution.


Assuntos
Carcinogênese , Carcinógenos/farmacologia , Neoplasias , Proteínas de Ligação a Retinoblastoma/genética , Ubiquitina-Proteína Ligases/genética , Sistemas CRISPR-Cas , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Linhagem Celular , Técnicas de Inativação de Genes , Predisposição Genética para Doença/genética , Humanos , Mutação/genética , Neoplasias/genética , Neoplasias/patologia , Oncogenes/genética
7.
Microbiol Spectr ; 10(1): e0231821, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-34985337

RESUMO

Lignocellulose degradation by microbial consortia is multifactorial; hence, it must be analyzed from a holistic perspective. In this study, the temporal transcriptional activity of consortium PM-06, a nixtamalized maize pericarp (NMP) degrader, was determined and related to structural and physicochemical data to give insights into the mechanism used to degrade this substrate. Transcripts were described in terms of metabolic profile, carbohydrate-active enzyme (CAZyme) annotation, and taxonomic affiliation. The PM-06 gene expression pattern was closely related to the differential rates of degradation. The environmental and physiological conditions preceding high-degradation periods were crucial for CAZyme expression. The onset of degradation preceded the period with the highest degradation rate in the whole process, and in this time, several CAZymes were upregulated. Functional analysis of expressed CAZymes indicated that PM-06 overcomes NMP recalcitrance through modular enzymes operating at the proximity of the insoluble substrate. Increments in the diversity of expressed modular CAZymes occurred in the last stages of degradation where the substrate is more recalcitrant and environmental conditions are stressing. Taxonomic affiliation of CAZyme transcripts indicated that Paenibacillus macerans was fundamental for degradation. This microorganism established synergistic relationships with Bacillus thuringiensis for the degradation of cellulose and hemicellulose and with Microbacterium, Leifsonia, and Nocardia for the saccharification of oligosaccharides. IMPORTANCE Nixtamalized maize pericarp is an abundant residue of the tortilla industry. Consortium PM-06 efficiently degraded this substrate in 192 h. In this work, the temporal transcriptional profile of PM-06 was determined. Findings indicated that differential degradation rates are important sample selection criteria since they were closely related to the expression of carbohydrate-active enzymes (CAZymes). The initial times of degradation were crucial for the consumption of nixtamalized pericarp. A transcriptional profile at the onset of degradation is reported for the first time. Diverse CAZyme genes were rapidly transcribed after inoculation to produce different enzymes that participated in the stage with the highest degradation rate in the whole process. This study provides information about the regulation of gene expression and mechanisms used by PM-06 to overcome recalcitrance. These findings are useful in the design of processes and enzyme cocktails for the degradation of this abundant substrate.


Assuntos
Bactérias/genética , Bactérias/metabolismo , Consórcios Microbianos , Zea mays/microbiologia , Bactérias/classificação , Bactérias/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Celulose/metabolismo , Perfilação da Expressão Gênica , Lignina/metabolismo , Polissacarídeos/metabolismo , Transcriptoma , Zea mays/metabolismo
8.
Plants (Basel) ; 10(9)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34579474

RESUMO

While it has been well evidenced that plant domestication affects the structure of the root-associated microbiome, there is a poor understanding of how domestication-mediated differences between rhizosphere microorganisms functionally affect microbial ecosystem services. In this study, we explore how domestication influenced functional assembly patterns of bacterial communities in the root-associated soil of 27 tomato accessions through a transect of evolution, from plant ancestors to landraces to modern cultivars. Based on molecular analysis, functional profiles were predicted and co-occurrence networks were constructed based on the identification of co-presences of functional units in the tomato root-associated microbiome. The results revealed differences in eight metabolic pathway categories and highlighted the influence of the host genotype on the potential functions of soil bacterial communities. In general, wild tomatoes differed from modern cultivars and tomato landraces which showed similar values, although all ancestral functional characteristics have been conserved across time. We also found that certain functional groups tended to be more evolutionarily conserved in bacterial communities associated with tomato landraces than those of modern varieties. We hypothesize that the capacity of soil bacteria to provide ecosystem services is affected by agronomic practices linked to the domestication process, particularly those related to the preservation of soil organic matter.

9.
Mutat Res ; 823: 111758, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34333390

RESUMO

Exposure to the ultraviolet (UV) radiation in sunlight creates DNA lesions, which if left unrepaired can induce mutations and contribute to skin cancer. The two most common UV-induced DNA lesions are the cis-syn cyclobutane pyrimidine dimers (CPDs) and pyrimidine (6-4) pyrimidone photoproducts (6-4PPs), both of which can initiate mutations. Interestingly, mutation frequency across the genomes of many cancers is heterogenous with significant increases in heterochromatin. Corresponding increases in UV lesion susceptibility and decreases in repair are observed in heterochromatin versus euchromatin. However, the individual contributions of CPDs and 6-4PPs to mutagenesis have not been systematically examined in specific genomic and epigenomic contexts. In this study, we compared genome-wide maps of 6-4PP and CPD lesion abundances in primary cells and conducted comprehensive analyses to determine the genetic and epigenetic features associated with susceptibility. Overall, we found a high degree of similarity between 6-4PP and CPD formation, with an enrichment of both in heterochromatin regions. However, when examining the relative levels of the two UV lesions, we found that bivalent and Polycomb-repressed chromatin states were uniquely more susceptible to 6-4PPs. Interestingly, when comparing UV susceptibility and repair with melanoma mutation frequency in these regions, disparate patterns were observed in that susceptibility was not always inversely associated with repair and mutation frequency. Functional enrichment analysis hint at mechanisms of negative selection for these regions that are essential for cell viability, immune function and induce cell death when mutated. Ultimately, these results reveal both the similarities and differences between UV-induced lesions that contribute to melanoma.


Assuntos
Reparo do DNA , Epigênese Genética/efeitos da radiação , Melanoma/genética , Mutação , Neoplasias Cutâneas/genética , Raios Ultravioleta/efeitos adversos , Dano ao DNA , Bases de Dados Genéticas , Eucromatina/química , Eucromatina/metabolismo , Eucromatina/efeitos da radiação , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Genoma Humano/efeitos da radiação , Heterocromatina/química , Heterocromatina/metabolismo , Heterocromatina/efeitos da radiação , Histonas/genética , Histonas/metabolismo , Humanos , Melanoma/etiologia , Melanoma/metabolismo , Melanoma/patologia , Mutagênese , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo , Cultura Primária de Células , Dímeros de Pirimidina/agonistas , Dímeros de Pirimidina/metabolismo , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
10.
J Pers Med ; 11(8)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34442382

RESUMO

Dental tissue-derived mesenchymal stem cells (DT-MSCs) are a promising resource for tissue regeneration due to their multilineage potential. Despite accumulating data regarding the biology and differentiation potential of DT-MSCs, few studies have investigated their adipogenic capacity. In this study, we have investigated the mesenchymal features of dental pulp stem cells (DPSCs), as well as the in vitro effects of different adipogenic media on these cells, and compared them to those of periodontal ligament stem cells (PLSCs) and dental follicle stem cells (DFSCs). DFSC, PLSCs, and DPSCs exhibit similar morphology and proliferation capacity, but they differ in their self-renewal ability and expression of stemness markers (e.g OCT4 andc-MYC). Interestingly, DFSCs and PLSCs exhibited more lipid accumulation than DPSCs when induced to adipogenic differentiation. In addition, the mRNA levels of adipogenic markers (PPAR, LPL, and ADIPOQ) were significantly higher in DFSCs and PLSCs than in DPSCs, which could be related to the differences in the adipogenic commitment in those cells. These findings reveal that the adipogenic capacity differ among DT-MSCs, features that might be advantageous to increasing our understanding about the developmental origins and regulation of adipogenic commitment.

11.
Environ Sci Pollut Res Int ; 28(32): 43507-43514, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33834340

RESUMO

The dissemination of antibiotic resistance genes (ARGs) in the environment contributes to the global rise in antibiotic resistant infections. Therefore, it is of importance to further research the exposure pathways of these emerging contaminants to humans. This study explores commercially available garden products containing animal manure as a source of ARGs in a survey of 34 garden products, 3 recently landscaped soils, and 5 native soils. DNA was extracted from these soils and quantified for 5 ARGs, intI1, and 16S rRNA. This study found that both absolute and relative gene abundances in garden products ranged from approximately two to greater than four orders of magnitude higher than those observed in native soils. Garden products with Organic Materials Review Institute (OMRI) certification did not have significantly different ARG abundances. Results here indicate that garden products are important sources of ARGs to gardens, lawns, and parks.


Assuntos
Antibacterianos , Jardins , Animais , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Humanos , Esterco , RNA Ribossômico 16S/genética , Solo , Microbiologia do Solo
12.
Nat Genet ; 52(11): 1178-1188, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33020667

RESUMO

Somatic mutations in driver genes may ultimately lead to the development of cancer. Understanding how somatic mutations accumulate in cancer genomes and the underlying factors that generate somatic mutations is therefore crucial for developing novel therapeutic strategies. To understand the interplay between spatial genome organization and specific mutational processes, we studied 3,000 tumor-normal-pair whole-genome datasets from 42 different human cancer types. Our analyses reveal that the change in somatic mutational load in cancer genomes is co-localized with topologically-associating-domain boundaries. Domain boundaries constitute a better proxy to track mutational load change than replication timing measurements. We show that different mutational processes lead to distinct somatic mutation distributions where certain processes generate mutations in active domains, and others generate mutations in inactive domains. Overall, the interplay between three-dimensional genome organization and active mutational processes has a substantial influence on the large-scale mutation-rate variations observed in human cancers.


Assuntos
Cromatina/química , Genoma Humano , Mutação , Neoplasias/genética , Linhagem Celular Tumoral , Cromossomos Humanos X/genética , Reparo de Erro de Pareamento de DNA , Análise Mutacional de DNA , DNA de Neoplasias , Conjuntos de Dados como Assunto , Feminino , Humanos , Masculino , Conformação Proteica , Domínios Proteicos , Dobramento de Proteína , Inativação do Cromossomo X
13.
PLoS One ; 15(10): e0239847, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33095792

RESUMO

Green lacewings (Neuroptera: Chrysopidae) are key biological control agents found in a broad range of crops. Given the importance of enhancing their presence and conservation, in this study, we aim to identify and to determine the relative importance of the pollen consumed by Chrysoperla lucasina (Lacroix, 1936) from 29 pollen types offered by 51 native plant species sown in an experimental farm in Villarrubia in the south of Spain. For the purposes of this study, C. lucasina specimens were captured in the late spring of 2016 and 2017. The pollen types and other components in the alimentary canal of C. lucasina were microscopically identified using the transparency method, which is a novel technique applied to green lacewings captured in the field. The results show that (i) C. lucasina feeds on over half of the pollen types offered by the sown plant species, with no differences in behaviour by sex or year; (ii) Capsella bursa-pastoris was the most frequently identified pollen type in the alimentary canal; (iii) the majority of pollen types identified correspond to sown native plant species and not to surrounding plant species; and that (iv) most of the adults studied also consumed honeydew. Our feeding study has important implications for the selection of plant mixtures for ground cover restoration and flower vegetation strips in Mediterranean agroecosystems, which complements our previous findings on how C. lucasina use native plant species as host and reproduction sites. The plant species Capsella bursa-pastoris and Biscutella auriculata, which are best suited to provide pollen, host and reproduction sites for C. lucasina in late spring, should consequently be included in the proposed plant mixtures for Mediterranean agroecosystems.


Assuntos
Dieta , Insetos/fisiologia , Pólen/classificação , Polinização , Animais , Feminino , Magnoliopsida , Masculino
14.
Am J Trop Med Hyg ; 103(5): 1803-1809, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32876005

RESUMO

The use of antimicrobial growth promoters in chicken farming has been commonly associated with high levels of antimicrobial resistance (AMR) in humans. Most of this work, however, has been focused on intensive large-scale operations. Intensive small-scale farming that regularly uses antibiotics is increasing worldwide and has different exposure pathways compared with large-scale farming, most notably the spatial connection between chickens and households. In these communities, free-ranging backyard chickens (not fed antibiotics) can roam freely, whereas broiler chickens (fed antibiotics) are reared in the same husbandry environment but confined to coops. We conducted an observational field study to better understand the spatial distribution of AMR in communities that conduct small-scale farming in northwestern Ecuador. We analyzed phenotypic resistance of Escherichia coli sampled from humans and backyard chickens to 12 antibiotics in relation to the distance to the nearest small-scale farming operation within their community. We did not find a statistically significant relationship between the distance of a household to small-scale farming and antibiotic-resistant E. coli isolated from chicken or human samples. To help explain this result, we monitored the movement of backyard chickens and found they were on average 17 m (min-max: 0-59 m) from their household at any given time. These backyard chickens on average ranged further than the average distance from any study household to its closest neighbor. This level of connectivity provides a viable mechanism for the spread of antimicrobial-resistant bacteria and genes throughout the community.


Assuntos
Antibacterianos/farmacologia , Galinhas , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Criação de Animais Domésticos , Animais , Demografia , Equador , Escherichia coli/isolamento & purificação , Humanos , Atividade Motora
15.
Ecotoxicol Environ Saf ; 200: 110734, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32464440

RESUMO

Microorganisms' role in pesticide degradation has been studied widely. Insitu treatments of effluents containing pesticides such as biological beds (biobeds) are efficient biological systems where biomixture (mixture of substrates) and microorganisms are the keys in pesticide treatment; however, microbial activity has been studied poorly, and its potential beyond biobeds has not been widely explored. In this study, the capacity of microbial consortium and bacteria-pure strains isolated from a biomixture (soil-straw; 1:1, v/v) used to treat agricultural effluents under real conditions were evaluated during a bioremediation process of five pesticides commonly used Yucatan Mexico. Atrazine, carbofuran, and glyphosate had the highest degradations (>90%) using the microbial consortium; 2,4-D and diazinon were the most persistent (DT50 = 8.64 and 6.63 days). From the 21 identified bacteria species in the microbial consortium, Pseudomonas nitroreducens was the most abundant (52%) according to identified sequences. For the pure strains evaluation 2,4-D (DT50 = 9.87 days), carbofuran (DT50 = 8.27 days), diazinon (DT50 = 8.80 days) and glyphosate (DT50 = 8.59 days) were less persistent in the presence of the mixed consortium (Ochrobactrum sp. DGG-1-3, Ochrobactrum sp. Ge-14, Ochrobactrum sp. B18 and Pseudomonas citronellolis strain ADA-23B). Time, pesticide, and strain type were significant (P < 0.05) in pesticide degradation, so this process is multifactorial. Microbial consortium and pure strains can be used to increase the biobed efficiency by inoculation, even in the remediation of soil contaminated by pesticides in agricultural areas.


Assuntos
Bactérias/metabolismo , Consórcios Microbianos , Praguicidas/metabolismo , Poluentes do Solo/metabolismo , Ácido 2,4-Diclorofenoxiacético/metabolismo , Agricultura , Atrazina/metabolismo , Bactérias/isolamento & purificação , Biodegradação Ambiental , Carbofurano/metabolismo , Diazinon/metabolismo , Glicina/análogos & derivados , Glicina/metabolismo , Pseudomonas/isolamento & purificação , Solo/química , Glifosato
16.
PeerJ ; 7: e8212, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824782

RESUMO

BACKGROUND: Dental pulp (DP) represents an accessible and valuable source promising of stem cells for clinical application. However, there are some disadvantages associated with the isolation of dental pulp stem cells (DPSCs), which include the size and weight of the pulp tissue needed to yield sufficient cells for culturing in vitro. Therefore, the objective of this study was to compare in vitro histomorphometry of DP from permanent (premolars, third molar), supernumerary and deciduous teeth of patients between 5 and 25 years old with regards to weight, length, width and the cell density in the four regions of the DP in order to obtain quantitative parameters in a tissue that represents a valuable source of stem cells. METHODS: DPs were obtained from 10 central incisors deciduous, 20 permanent teeth (10 premolars, 10 third molars) and 10 supernumeraries (six mesiodents and four inferior premolar shapes). The pulps were carefully removed, and the entire tissue was weighed. The pulp length and the width were measured with a digital Vernier caliper. The cellular density analysis was performed according to the four regions of the DP (coronal, cervical, medial and apical) in histological slides using photography and the ImageJ® program for quantification. RESULTS: The Pearson correlation test revealed that DP weight among different types of teeth is correlated with age in male patients. A significant positive correlation was noted between length and width of the DP with age in both genders. The mean DP weight for supernumerary and third molar teeth was greater than deciduous and premolar teeth. Finally, the histological analysis showed that the coronal and apical portions of DP in supernumerary and premolar teeth have the highest cell density. CONCLUSIONS: The DP of supernumerary teeth has quantitatively the best morphometric parameters and cell density comparable with the quality of DP obtained from deciduous teeth.

17.
Nat Ecol Evol ; 3(12): 1754-1761, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31712699

RESUMO

Higher levels of taxonomic and evolutionary diversity are expected to maximize ecosystem function, yet their relative importance in driving variation in ecosystem function at large scales in diverse forests is unknown. Using 90 inventory plots across intact, lowland, terra firme, Amazonian forests and a new phylogeny including 526 angiosperm genera, we investigated the association between taxonomic and evolutionary metrics of diversity and two key measures of ecosystem function: aboveground wood productivity and biomass storage. While taxonomic and phylogenetic diversity were not important predictors of variation in biomass, both emerged as independent predictors of wood productivity. Amazon forests that contain greater evolutionary diversity and a higher proportion of rare species have higher productivity. While climatic and edaphic variables are together the strongest predictors of productivity, our results show that the evolutionary diversity of tree species in diverse forest stands also influences productivity. As our models accounted for wood density and tree size, they also suggest that additional, unstudied, evolutionarily correlated traits have significant effects on ecosystem function in tropical forests. Overall, our pan-Amazonian analysis shows that greater phylogenetic diversity translates into higher levels of ecosystem function: tropical forest communities with more distantly related taxa have greater wood productivity.


Assuntos
Ecossistema , Madeira , Florestas , Filogenia , Clima Tropical
18.
Int J Mol Sci ; 20(16)2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31408999

RESUMO

Obesity is a rising public health problem that contributes to the development of several metabolic diseases and cancer. Adipocyte precursors outside of adipose depots that expand due to overweight and obesity may have a negative impact on human health. Determining how progenitor cells acquire a preadipocyte commitment and become mature adipocytes remains a significant challenge. Over the past several years, we have learned that the establishment of cellular identity is widely influenced by changes in histone marks, which in turn modulate chromatin structure. In this regard, histone lysine demethylases (KDMs) are now emerging as key players that shape chromatin through their ability to demethylate almost all major histone methylation sites. Recent research has shown that KDMs orchestrate the chromatin landscape, which mediates the activation of adipocyte-specific genes. In addition, KDMs have functions in addition to their enzymatic activity, which are beginning to be revealed, and their dysregulation seems to be related to the development of metabolic disorders. In this review, we highlight the biological functions of KDMs that contribute to the establishment of a permissive or repressive chromatin environment during the mesenchymal stem cell transition into adipocytes. Understanding how KDMs regulate adipogenesis might prompt the development of new strategies for fighting obesity-related diseases.


Assuntos
Adipogenia , Epigênese Genética , Histona Desmetilases/metabolismo , Histonas/metabolismo , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Cromatina/genética , Cromatina/metabolismo , Histona Desmetilases/genética , Histonas/genética , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo
19.
AMB Express ; 9(1): 85, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197616

RESUMO

The nixtamalized maize pericarp (NMP) is a plentiful by-product of the tortilla industry and an important source of fermentable sugars. The aim of this study was to describe the degradation profile of NMP by the action of a consortium (PM-06) obtained from the native microbial community of this residue. The degradation was analyzed in terms of the changes in the community dynamics, production of enzymes (endo-xylanase and endo-cellulase), physicochemical parameters, and substrate chemical and microstructural characteristics, to understand the mechanisms behind the process. The consortium PM-06 degraded 86.8 ± 3.3% of NMP after 192 h of growth. Scanning electron microscopy images, and the composition and weight of the residual solids, showed that degradation was sequential starting with the consumption of hemicellulose. Xylanase was the highest enzyme activity produced, with a maximum value of 12.45 ± 0.03 U mL-1. There were fluctuations in the pH during the NMP degradation, starting with the acidification of the culture media and finishing with a pH close to 8.5. The most abundant species in the consortium, at the moment of maximum degradation activity, were Aneurinibacillus migulanus, Paenibacillus macerans, Bacillus coagulans, Microbacterium sp. LCT-H2, and Bacillus thuringiensis. The diversity of PM-06 provided metabolic abilities that in combination helped to produce an efficient process. The consortium PM-06 generated a set of different tools that worked coordinated to increase the substrate availability through the solubilization of components and elimination of structural diffusion barriers. This is the first report about the degradation of NMP using a microbial consortium.

20.
Psychol. av. discip ; 13(1): 13-24, ene.-jun. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1250584

RESUMO

Resumen El objetivo del presente estudio fue analizar la relación entre el estilo de apego parental y los celos románticos en un grupo de jóvenes universitarios colombianos entre los 18 y 25 años. Participaron de manera voluntaria 614 jóvenes, 421 mujeres (69%) y 193 hombres (31%), con una relación de pareja vigente de más de seis meses de duración. Los instrumentos utilizados fueron el Inventario de Apego con Padres y Pares (IPPA, Armsden y Greenberg, 1987, adaptada por Rocha, Benítez, De-Irala, sin publicar), con el cual se evaluó el apego parental con respecto a su cuidador primario, y la Escala Interpersonal de Celos (Mathes y Severa, 1981, adaptada por Martínez-León, Mathes, Avendaño, Peña y Sierra, 2018) con la cual se midieron los celos románticos en la relación de pareja de los participantes. Los resultados mostraron que en la variable estrato socioeconómico nivel medio (estratos 3 y 4) existe una relación significativa (p = .023) la cual indica que, en esta muestra específica, el estilo de apego parental está asociado con el nivel de los celos románticos en la relación de pareja.


Abstract The objective of the present study is to analyze the relationship between parental attachment style and romantic jealousy in a group of Colombian students between 18 and 25 years old. Volunteers participated 614 young people, 421 (69%) women and 193 (31%) men, with a current relationship of more than six months. The instruments used were the Inventory of Attachment with Parents and Peers (IPPA, Armsden y Greenberg, 1987, adapted by Rocha, Benítez, De-Irala, unpublished), with which assessed parental attachment with respect to their primary caregiver, and the Interpersonal Scale of Jealousy (Mathes & Severa, 1981, adapted by Martínez-León, Mathes, Avendaño, Peña and Sierra, 2018), with which was measured romantic jealousy in the couple's relationship of the participants. The results showed that in the variable socioeconomic mid-level (strata 3 and 4) there is a significant relationship (p = .023) which indicates that, in this specific sample, the Parental attachment style is associated with the level of romantic jealousy in the couple's relationship.


Assuntos
Associação , Poder Familiar , Ciúme , Apego ao Objeto , Mulheres , Luto , Terapia de Casal/normas , Depressão , Emoções , Relações Interpessoais , Homens
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