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1.
Front Psychiatry ; 14: 1214192, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38179248

RESUMO

Objective: We aimed to investigate the characteristics and psychological mechanism of non-suicidal self-injury (NSSI) in adolescents with mood disorders. We examined how self-compassion and emotional regulation affected NSSI and tested the mediating role of self-compassion in the link between emotional regulation and NSSI. Method: We recruited outpatient and inpatient adolescent patients with bipolar and related disorders or depressive disorders (DSM-5), with a focus on NSSI. We also recruited healthy controls from the community. We collected demographic and clinical data. The Adolescent Self-injury Questionnaire, Self-compassion Scale (SCS), and Emotion Regulation Questionnaire (ERQ) were used to assess the frequency and severity of NSSI, level of self-compassion, and emotional regulation. Results: In total, we recruited 248 adolescent patients with mood disorders (N = 196 with NSSI, and 52 without NSSI) and 212 healthy controls. NSSI was significantly associated with the female sex, lower levels of education and less use of cognitive reappraisal strategies, lower levels of self-warmth, and higher levels of self-coldness. Multivariate analysis of variance showed that there were significant differences in the scores of ERQ, cognitive reassessment score, and the scores of SCS among the three groups, but no statistical differences in expressive suppression score among the three groups. Self-warmth had a mediating effect between cognitive reappraisal and NSSI behavior. Conclusion: NSSI is prevalent among adolescent patients with mood disorders in clinical settings, especially among girls and those with lower levels of education and less cognitive reappraisal strategies. More clinical attention is needed. Self-compassion and its factors may mediate the association between emotional regulation and NSSI. Clinical implications and future research directions were discussed.

2.
Sci Total Environ ; 853: 158630, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36084783

RESUMO

Exoelectrogens possess extraordinary degradation ability to various pollutants through extracellular electron transfer (EET). Compared with extracellular electron release process, intracellular electron transfer network is not yet fully recognized. Especially, controversy remains regarding the role of CymA, an essential electron-transfer hub of Shewanella oneidensis MR-1, in EET process. In this study, we thoroughly surveyed the intracellular transfer strategies during EET through dye decolorization. Loss of CymA severely impaired the reduction ability of S. oneidensis MR-1 to methyl orange (MO), but hardly affected the decolorization of aniline blue (AB). Complement of cymA fully restored the MO decolorization ability of ΔcymA mutant. The contribution of CymA to extracellular decolorization was subjected to MO concentrations. The defect in the decolorization ability of ΔcymA mutant was not evident at low MO concentration, but severe at high MO concentration. Further investigation revealed that EET rate determined the significance of CymA in the extracellular bioremediation by S. oneidensis MR-1. Coupled with MO concentrations increasing from 15 to 120 mg/L, the initial electron transfer rates of S. oneidensis MR-1 increased accordingly from 2.69 × 104 to 11.21 × 104 electrons CFU-1 s-1, which led to a gradual increase of the dependencyCymA. Thus, we first revealed that extracellular degradation performance could feedback regulate the intracellular electron transfer process of S. oneidensis MR-1. This work is helpful to fully understand the complex EET process of exoelectrogens and facilitates the application of exoelectrogens in bioremediation of environmental pollutants.


Assuntos
Poluentes Ambientais , Shewanella , Elétrons , Poluentes Ambientais/metabolismo , Retroalimentação , Shewanella/metabolismo , Transporte de Elétrons
3.
Environ Microbiol ; 24(11): 5292-5305, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36054579

RESUMO

Genetic engineering is promising to expand the application scope of exoelectrogens in energy and environmental applications and plasmid vectors, as one type of fundamental tool, are intensively applied. Antibiotics are widely utilized for plasmid selection and maintenance; however, their utilization suffers from environmental concerns on the spread of resistance genes, elevated costs, inevitable genotypic instability and phenotypic heterogeneity. In this work, we establish an auxotrophic complementation system for stable plasmid maintenance without antibiotic association, in Shewanella oneidensis, an attractive model exoelectrogen. A plasmid-transition strategy is designed to facilitate the rapid and efficient construction of the auxotrophic complementation system. Such a system not only enables the same intensive gene expression as the conventional antibiotic-associated plasmid system but also exhibits remarkably superior robustness and stability. With this system, the menaquinone pool of the extracellular respiratory chain is enhanced first independently and further synergized by engineering the Mtr conduit, leading to significantly promoted extracellular electron transfer (EET) outputs (up to 10.33- and 2.97-fold improvement in the maximum current density and the maximum output voltage) and heavy metal Cr(VI) reduction ability (5.15-fold improvement). This work provides a robust and stable platform to engineer exoelectrogens for environmental applications.


Assuntos
Shewanella , Shewanella/genética , Shewanella/metabolismo , Plasmídeos/genética , Transporte de Elétrons , Respiração Celular , Antibacterianos/metabolismo
4.
Chemosphere ; 291(Pt 2): 132824, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34752835

RESUMO

Numerous studies have shown that zinc oxide nanoparticles (nZnO) have an inhibitory effect on wastewater biotreatment, where doses exceeding ambient concentrations are used. However, the effect of ambient concentrations of ZnO (<1 mg/L) on anaerobic digestion processes is not clear. Herein, this study comprehensively explored the impact of nZnO on the denitrification performance and core microbial community of activated sludge under ambient concentrations. Results showed that only 0.075 mg/L nZnO had shown a beneficial effect on nitrogen removal by activated sludge. When nZnO concentration reached 0.75 mg/L, significant enhancement of nitrate reduction and mitigation of nitrite accumulation were observed, indicating a remarkable stimulatory effect on nitrogen removal. Simultaneously, nZnO could weaken the sludge surface charge and improve the secretion of extracellular polymeric substances, thus enhancing sludge flocculation for denitrification. Microbial community analysis revealed that nZnO exposure increased the relative abundance of denitrifying bacteria, which could contribute to the reinforcement of traditional denitrification. Furthermore, exogenous addition of NH4+ significantly inhibited the accumulation of nitrite, implying that nZnO had a potential to improve the denitrification process via a partial denitrification-anammox pathway. Considering current ambient concentration, the stimulatory effect shown in our work may better represent the actual behavior of ZnO in wastewater biotreatment.


Assuntos
Desnitrificação , Nanopartículas , Oxidação Anaeróbia da Amônia , Reatores Biológicos , Nitrogênio , Oxirredução , Esgotos , Águas Residuárias
5.
Front Psychiatry ; 12: 747031, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34916971

RESUMO

Non-suicidal self-injury (NSSI) in adolescents is an increasing public health problem in China. We conducted a meta-analysis of studies on NSSI in Chinese adolescents (between 10 and 19 years) to examine factors associated with NSSI. Twenty-five papers including 30 separate studies with 186,447 participants were included for analysis. The results from a random-effects model showed a weak, but significant overall prediction of NSSI (OR = 1.734). There were significant associations between the following seven factors and NSSI (ranking by the effect sizes, in descending order): adverse life events (OR = 2.284), negative coping style (OR = 2.040), problematic internet use (OR = 2.023), sleep disturbance (OR = 1.734), traumatic experiences (OR = 1.728), problematic parent-child relationship (OR = 1.585), mental health problems (OR = 1.578). Additionally, NSSI sample type moderated these effects. These findings highlight factors significantly associated with NSSI in Chinese adolescents. Parent-child relationship and mental health of the only children and left-behind children in China deserve more attention. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42019123508.

6.
Environ Sci Technol ; 55(17): 11997-12008, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34378391

RESUMO

Dissimilatory metal-reducing bacteria (DMRB) with extracellular electron transfer (EET) capability show great potential in bioremediating the subsurface environments contaminated by uranium through bioreduction and precipitation of hexavalent uranium [U(VI)]. However, the low EET efficiency of DMRB remains a bottleneck for their applications. Herein, we develop an engineered CRISPR platform to drive the extracellular electron pumping of Shewanella oneidensis, a representative DMRB species widely present in aquatic environments. The CRISPR platform allows for highly efficient and multiplex genome editing and rapid platform elimination post-editing in S. oneidensis. Enabled by such a platform, a genomic promoter engineering strategy (GPS) for genome-widely engineering the EET-encoding gene network was established. The production of electron conductive Mtr complex, synthesis of electron shuttle flavin, and generation of NADH as intracellular electron carrier are globally optimized and promoted, leading to a significantly enhanced EET ability. Applied to U(VI) bioreduction, the edited strains achieve up to 3.62-fold higher reduction capacity over the control. Our work endows DMRB with an enhanced ability to remediate the radionuclides-contaminated environments and provides a gene editing approach to handle the growing environmental challenges of radionuclide contaminations.


Assuntos
Shewanella , Urânio , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Transporte de Elétrons , Elétrons , Shewanella/genética
7.
Sci Total Environ ; 794: 148765, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34225149

RESUMO

Nanoparticles released into the environment are attracting increasing concern because of their potential toxic effects. Conventional methods for assessing the toxicity of nanoparticles are usually confined to cultivable cells, but not applicable to viable but non-culturable (VBNC) cells. However, it remains unknown whether silver nanoparticles (AgNPs), a typical antimicrobial agent, could induce bacteria into a VBNC state in natural environments. In this work, the viability of E. coli, an indicator bacterium widely used for assessing the antibacterial activity of AgNPs, was examined through coupling plate counting, fluorescence staining and adenosine triphosphate (ATP) production. AgNPs were found to have a considerable antibacterial ability, which resulted in less than 0.0004% of culturable cells on plates. However, more than 80% of the cells still maintained their cell membrane integrity under the stress of 80 mg/L AgNPs. Meanwhile, the residue of ATP production (0.6%) was 1500 times higher than that of the culturable cells (< 0.0004%). These results clearly demonstrate that when exposed to AgNPs, most of cells fell into a VBNC state, instead of dying. Environmental factors, e.g., Cl- and illumination, which could change the dissolution, hydrophilicity and zeta potential of AgNPs, eventually influenced the culturability of E. coli. Inhibition of dissolved Ag+ and reactive oxygen species was found to facilitate the mitigation of the strain into a VBNC state. Our findings suggest the necessity of re-evaluating the environmental effects and antibacterial activities of AgNPs.


Assuntos
Escherichia coli , Nanopartículas Metálicas , Antibacterianos/toxicidade , Sobrevivência Celular , Nanopartículas Metálicas/toxicidade , Prata/toxicidade
8.
Environ Microbiol ; 23(2): 1238-1255, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33369000

RESUMO

The advances in synthetic biology bring exciting new opportunities to reprogram microorganisms with novel functionalities for environmental applications. For real-world applications, a genetic tool that enables genetic engineering in a stably genomic inherited manner is greatly desired. In this work, we design a novel genetic device for rapid and efficient genome engineering based on the intron-encoded homing-endonuclease empowered genome editing (iEditing). The iEditing device enables rapid and efficient genome engineering in Shewanella oneidensis MR-1, the representative strain of the electroactive bacteria group. Moreover, combining with the Red or RecET recombination system, the genome-editing efficiency was greatly improved, up to approximately 100%. Significantly, the iEditing device itself is eliminated simultaneously when genome editing occurs, thereby requiring no follow-up to remove the encoding system. Then, we develop a new extracellular electron transfer (EET) engineering strategy by programming the parallel EET systems to enhance versatile EET. The engineered strains exhibit sufficiently enhanced electron output and pollutant reduction ability. Furthermore, this device has demonstrated its great potential to be extended for genome editing in other important microbes. This work provides a useful and efficient tool for the rapid generation of synthetic microorganisms for various environmental applications.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Elétrons , Engenharia Genética/métodos , Genoma Bacteriano/genética , Biodegradação Ambiental , Transporte de Elétrons/genética , Poluentes Ambientais/metabolismo , Edição de Genes/instrumentação , Engenharia Genética/instrumentação , Recombinação Genética , Shewanella/genética , Shewanella/metabolismo
9.
Proc Natl Acad Sci U S A ; 117(37): 23001-23010, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32855303

RESUMO

The unique extracellular electron transfer (EET) ability has positioned electroactive bacteria (EAB) as a major class of cellular chassis for genetic engineering aimed at favorable environmental, energy, and geoscience applications. However, previous efforts to genetically enhance EET ability have often impaired the basal metabolism and cellular growth due to the competition for the limited cellular resource. Here, we design a quorum sensing-based population-state decision (PSD) system for intelligently reprogramming the EET regulation system, which allows the rebalanced allocation of the cellular resource upon the bacterial growth state. We demonstrate that the electron output from Shewanella oneidensis MR-1 could be greatly enhanced by the PSD system via shifting the dominant metabolic flux from initial bacterial growth to subsequent EET enhancement (i.e., after reaching a certain population-state threshold). The strain engineered with this system achieved up to 4.8-fold EET enhancement and exhibited a substantially improved pollutant reduction ability, increasing the reduction efficiencies of methyl orange and hexavalent chromium by 18.8- and 5.5-fold, respectively. Moreover, the PSD system outcompeted the constant expression system in managing EET enhancement, resulting in considerably enhanced electron output and pollutant bioreduction capability. The PSD system provides a powerful tool for intelligently managing extracellular electron transfer and may inspire the development of new-generation smart bioelectrical devices for various applications.


Assuntos
Transporte de Elétrons/fisiologia , Shewanella/fisiologia , Respiração Celular/fisiologia , Cromo/metabolismo , Elétrons , Percepção de Quorum/fisiologia , Shewanella/metabolismo
10.
Environ Sci Technol ; 54(6): 3599-3608, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32062962

RESUMO

Pursuing efficient approaches to promote the extracellular electron transfer (EET) of extracellular respiratory bacteria is essential to their application in environmental remediation and waste treatment. Here, we report a new strategy of tuning electron flux by clustered regularly interspaced short palindromic repeat (CRISPR)-ddAsCpf1-based rediverting (namely STAR) to enhance the EET capacity of Shewanella oneidensis MR-1, a model extracellular respiratory bacterium widely present in the environment. The developed CRISPR-ddAsCpf1 system enabled approximately 100% gene repression with the green fluorescent protein (GFP) as a reporter. Using a WO3 probe, 10 representative genes encoding for putative competitive electron transfer proteins were screened, among which 7 genes were identified as valid targets for EET enhancement. Repressing the valid genes not only increased the transcription level of the l-lactate metabolism genes but also affected the genes involved in direct and indirect EET. Increased riboflavin production was also observed. The feasibility of this strategy to enhance the bioreduction of methyl orange, an organic pollutant, and chromium, a typical heavy metal, was demonstrated. This work implies a great potential of the STAR strategy with the CIRPSR-ddAsCpf1 system for enhancing bacterial EET to favor more efficient environmental remediation applications.


Assuntos
Poluentes Ambientais , Shewanella , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Transporte de Elétrons , Elétrons
11.
J AOAC Int ; 102(5): 1448-1454, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31088594

RESUMO

Background: The essential oil content of the water lily is extremely low; thus, finding a new method that can extract essential oil from water lilies with a high extraction rate and no residual organic solvents is essential. Objective: The optimal processing conditions for the ultrasound-enhanced subcritical fluid extraction of essential oil from Nymphaea alba var (red water lily) and the antioxidant activity of the essential oil in vitro are investigated to provide theoretical bases for identification and development. Methods: Single-factor experiments and orthogonal designs are performed to determine the effects of extraction conditions on essential oil yields. The chemical composition of essential oil is analyzed using GC-MS. Results: The optimum extraction parameters are established as follows: extraction temperature, 35°C; extraction time, 30 min/time for four times; ratio of material to liquid, 1:3; ultrasound power, 250 W/L; and ultrasonic frequency, 20 kHz. The extraction rate of essential oil is 0.315% under these conditions. Eleven components comprise more than 1% content. The main chemical constituents are 8-hexadecyne (31.04%) and 2,6,10-trimethyl-tetradecane (3.95%). The essential oil from N. alba var has an antioxidant activity in vitro; however, its antioxidant activity is weaker than that of butylated hydroxytoluene. Conclusions: Subcritical fluid is suitable for the extraction of essential oil from N. alba var, and the essential oil has a good antioxidant activity. Highlights: The essential oil content of N. alba var is 0.315%. Forty-seven chemical constituents are identified and isolated from N. alba var and analyzed by GC-MS.


Assuntos
Antioxidantes/química , Nymphaea/química , Óleos Voláteis/química , Óleos de Plantas/química , Extração em Fase Sólida/métodos , Antioxidantes/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/isolamento & purificação , Óleos de Plantas/isolamento & purificação , Ondas Ultrassônicas
12.
Environ Pollut ; 250: 233-240, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30999200

RESUMO

Microbes in sediments contribute to nutrient release and play an important role in lake eutrophication. However, information about the profiles of functional genes and bacterial communities and the most important environmental factor affecting them in the sediments of eutrophic lake remains unrevealed. In this work, the real-time fluorescent quantitative polymerase chain reaction (qPCR) assay and 16S ribosomal RNA gene next generation sequencing analysis were used to explore the profiles of functional genes and bacterial communities in the sediments of Chaohu Lake. The selected 18 functional genes involved in C, N and P cycles were detected in most of samples. Seasonal variation and sediment variables were found to affect the profiles of functional genes and bacterial communities, and total nitrogen was the dominant environmental factor to drive the formation of bacterial community structure. Proteobacteria and Firmicutes were observed to be the two dominant phyla in the sediments with relative abundance ranging from 10.8% to 36.0% and 7.7%-46.7%, respectively. Three bacterial phyla, i.e., Actinobacteria, Proteobacteria, and Spirochaetes, were found to be significantly positively correlated with the C, N and P-cycle related functional genes. Bacterial community structure was the most important driver to shape the profiles of functional genes. Seasonal variation also influenced the co-occurrence patterns between functional genes and bacterial taxa as revealed by network analysis. The findings from this work facilitate a better understanding about the C, N, and P cycles in the sediments of eutrophic lakes.


Assuntos
Sedimentos Geológicos/microbiologia , Lagos/microbiologia , Microbiota/genética , Nitrogênio/química , Estações do Ano , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Proteínas de Bactérias/genética , Eutrofização , Sedimentos Geológicos/química , Lagos/química , Nitrogênio/metabolismo , RNA Ribossômico 16S/genética , Microbiologia da Água
13.
Sci Total Environ ; 657: 1014-1022, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30677869

RESUMO

Municipal wastewater treatment plants (WWTPs) are an important reservoir for heavy metal (e.g., Hg and Ag) resistance genes and antibiotic resistance genes (ARGs). However, current knowledge on Hg/Ag resistance genes and their association with ARGs in WWTPs remains largely unknown. In this study, the fates of five Hg/Ag resistance genes (merB, merD, merR, silE, and silR), five ARGs (sulI, sulII, tetO, tetQ, tetW), and class 1 integrase (intI1) in a WWTP were investigated. Results show that the absolute abundances of all target genes were greatly reduced through the treatment systems. The dynamics of merB, merD and silE were significantly correlated with tetW and sulII. Based on network analysis, Hg/Ag resistance genes might share the same microbial hosts with tetQ and tetW, implying the potential importance of Hg/Ag in ARGs evolution and spread. These findings advanced our understanding of the occurrence of Hg/Ag resistance genes and ARGs in WWTPs.


Assuntos
Resistência Microbiana a Medicamentos/genética , Mercúrio/farmacologia , Microbiota/genética , Prata/farmacologia , Eliminação de Resíduos Líquidos/métodos , Proteínas de Bactérias/genética , Reatores Biológicos/microbiologia , Proteínas de Transporte/genética , China , Proteínas de Ligação a DNA/genética , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Filtração , Halogenação , Liases/genética , Microbiota/efeitos dos fármacos , Águas Residuárias/microbiologia , Áreas Alagadas
14.
Appl Microbiol Biotechnol ; 102(24): 10791-10801, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30334090

RESUMO

Iron reduction mediated by Fe(III)-reducing bacteria (FeRB) occurs in aqueous environments and plays an essential role in removing contaminates in polluted freshwater lakes. Two model FeRB species, Shewanella and Geobacter, have been intensively studied because of their functions in bioremediation, iron reduction, and bioelectricity production. However, the abundance and community diversity of Shewanella and Geobacter in eutrophic freshwater lakes remain largely unknown. In this work, the distribution, abundance and biodiversity of Shewanella, Geobacter and other FeRB in the sediments of a heavily polluted lake, Chaohu Lake, China, across four successive seasons were investigated. Shewanella, Geobacter, and other FeRB were found to be widely distributed in the sediment of this heavily eutrophic lake. Geobacter was abundant with at least one order of magnitude more than Shewanella in cold seasons. Three Shewanella-related operational taxonomic units were detected and sixty one Geobacter-related operational taxonomic units were grouped into three phylogenetic clades. Thiobacillus, Desulfuromonas and Geobacter were identified as the main members of FeRB in the lake sediments. Interestingly, nutrients like carbon, nitrogen, and phosphorus were found to be the key factors governing the abundance and diversity of FeRB. Total FeRB, as well as Geobacter and Shewanella, were more abundant in the heavily eutrophic zone than those in the lightly eutrophic zone. The abundance and diversity of FeRB in the sediments of freshwater lakes were highly related with the degree of eutrophication, which imply that FeRB might have a great potential in alleviating the eutrophication and contamination in aqueous environments.


Assuntos
Geobacter , Sedimentos Geológicos/microbiologia , Ferro/metabolismo , Lagos/microbiologia , Shewanella , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , China , Clonagem Molecular , Eutrofização , Geobacter/genética , Geobacter/isolamento & purificação , Sedimentos Geológicos/química , Sequenciamento de Nucleotídeos em Larga Escala , Oxirredução , Filogenia , Shewanella/genética , Shewanella/isolamento & purificação , Microbiologia da Água , Poluição da Água
15.
Nat Commun ; 9(1): 3037, 2018 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-30072717

RESUMO

Besides its mathematical importance, the Möbius topology (twisted, single-sided strip) is intriguing at the molecular level, as it features structural elegance and distinct properties; however, it carries synthetic challenges. Although some Möbius-type molecules have been isolated by synthetic chemists accompanied by extensive computational studies, the design, preparation, and characterization of stable Möbius-conjugated molecules remain a nontrivial task to date, let alone that of molecular Möbius strips assembling into more complex topologies. Here we report the efficient synthesis, crystal structure, and theoretical study of a catenane consisting of two fully conjugated nanohoops exhibiting Möbius topology in the solid state. This work highlights that oligoparaphenylene-derived nanohoops, a family of highly warped and synthetically challenging conjugated macrocycles, can not only serve as building blocks for interlocked supermolecular structures, but also represent a new class of compounds with isolable Möbius conformations stabilized by non-covalent interactions.

16.
Sci Total Environ ; 637-638: 926-933, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29763873

RESUMO

Shewanella species have a diverse respiratory ability and wide distribution in environments and play an important role in bioremediation and the biogeochemical cycles of elements. Primers with more accuracy and broader coverage are required with consideration of the increasing number of Shewanella species and evaluation of their roles in various environments. In this work, a new primer set of 640F/815R was developed to quantify the abundance of Shewanella species in natural and engineered environments. In silico tools for primer evaluation, quantitative polymerase chain reaction (qPCR) and clone library results showed that 640F/815R had a higher specificity and coverage than the previous primers in quantitative analysis of Shewanella. Another newly developed primer pair of 211F/815cR was also adopted to analyze the Shewanella diversity and demonstrated to be the best candidate in terms of specificity and coverage. We detected more Shewanella-related species in freshwater environments and found them to be substantially different from those in marine environments. Abundance and diversity of Shewanella species in wastewater treatment plants were largely affected by the process and operating conditions. Overall, this study suggests that investigations of abundance and diversity of Shewanella in various environments are of great importance to evaluate their ecophysiology and potential ecological roles.


Assuntos
Monitoramento Ambiental/métodos , Shewanella/crescimento & desenvolvimento , Águas Residuárias/microbiologia , Microbiologia da Água , Biodegradação Ambiental , Primers do DNA , Filogenia , Reação em Cadeia da Polimerase , Shewanella/classificação
17.
Plant Genome ; 10(2)2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28724071

RESUMO

Adaptation is a characteristic that enhances the survival or reproduction of organisms; selection is the critical process leading to adaptive evolution. Therefore, detecting selection is important in studying evolutionary biology. Changes in allele frequency are fundamental to adaptive evolution. The allele frequency of entire genes at the genomic scale is more intensive and precise for analyzing selection effects, compared with simple sequence repeat and single nucleotide polymorphism (SNP) alleles from nuclear gene fragments. Here, we analyzed 29,094 SNPs derived from 80 individuals of 14 L. Liou ex S.L. Chen & Renvoize populations planted near their native habitat (Jiangxia, Hubei Province, JH) and a stressful environment (Qingyang, Gansu Province, QG) to detect selection during initial adaptation. The nucleotide diversity of over 60% of genes was decreased in QG compared with JH, suggesting that most genes were undergoing selection in the stressful environment. We explored a new approach based on haplotype data inferred from RNA-seq data to analyze the change in frequency between two sites and to detect selection signals. In total, 402 and 51 genes were found to be targets of positive and negative selection, respectively. Among these candidate genes, the enrichment of abiotic stress-response genes and photosynthesis-related genes might have been responsible for establishment in the stressful environment. This is the first study assessing the change in allele frequency at the genomic level during adaptation. The method in which allele frequency detects selection during initial adaptation using population RNA-seq data would be useful for developing evolutionary biology.


Assuntos
Haplótipos , Poaceae/genética , Seleção Genética , Transcriptoma , Frequência do Gene , Genes de Plantas , Variação Genética , Polimorfismo de Nucleotídeo Único
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(3): 836-40, 2017 Mar.
Artigo em Chinês, Inglês | MEDLINE | ID: mdl-30160391

RESUMO

In order to realize rapid identification of dried red jujubes, this paper proposes a method based on near-infrared hyperspectral imaging technology. The near-infrared hyperspectral images (1 000~1 600 nm) of 240 samples in total from 4 cultivars of dried red jujubes will be acquired. The samples are to be divided into the calibration set and the prediction set in the ratio of 2∶1. 7, 8, 10 effective wavelengths are to be selected by principal component analysis(PCA), x-loading weight(x-LW)and successive projection algorithm(SPA) respectively. The dimensionality of original hyperspectral images will be reduced with PCA, and texture features of the first principal component image are to be extracted with gray-level co-occurrence matrix(GLCM).The partial least squares-discriminant analysis(PLS-DA), back propagation neural network(BPNN)and least square support vector machine(LS-SVM) are to be applied to build identification models with the selected effective wavelengths, texture features and fusion of the former two features. The identification rates of the models based on fusion features will be higher than those of models based on the spectral features or texture features respectively. The BPNN models based on the fusion features will obtain the best results, whose identification rates of prediction set are to be 100%. The results in this paper indicate that the near-infrared hyperspectral imaging technology has great potential to identify the dried red jujubes rapidly.

19.
J Zhejiang Univ Sci B ; 17(2): 127-35, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26834013

RESUMO

Based on bioinformatic analysis, we selected two novel microRNAs (miRNAs), bmo-miR-0001 and bmo-miR-0015, from high-throughput sequencing of the Bombyx mori larval posterior silk gland (PSG). Firstly, we examined the expression of bmo-miR-0001 and bmo-miR 12 different tissues of the 5th instar Day-3 larvae of the silkworm. The results showed that the expression levels of both bmo-miR-0001 and bmo-miR-0015 were obviously higher in the PSG than in other tissues, implying there is a spatio-temporal condition for bmo-miR-0001 and bmo-miR-0015 to regulate the expression of BmFib-L. To test this hypothesis, we constructed pri-bmo-miR-0001 expressing the plasmid pcDNA3.0 and pri-bmo-miR-0015 expressing the plasmid pcDNA3.0 [ie1-egfp-pri-bmo-miR-0015-SV40]. Finally, the BmN cells were harvested and luciferase activity was detected. The results showed that luciferase activity was reduced significantly (P<0.05) in BmN cells co-transfected by pcDNA3.0 [ie1-egfp-pri-bmo-miR-0001-SV40] or pcDNA3.0 with pGL3.0 [A3-luc-Fib-L-3'UTR-SV40], suggesting that both bmo-miR-0001 and bmo-miR-0015 can down-regulate the expression of BmFib-L in vitro.


Assuntos
Bombyx/metabolismo , Regulação para Baixo/fisiologia , Fibroínas/metabolismo , Proteínas de Insetos/metabolismo , MicroRNAs/metabolismo , Animais , Bombyx/genética , Fibroínas/genética , Proteínas de Insetos/genética , MicroRNAs/genética , Especificidade de Órgãos , Distribuição Tecidual
20.
J Steroid Biochem Mol Biol ; 155(Pt A): 104-11, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26462682

RESUMO

The role of progesterone on the cardiovascular system is controversial. Our present research is to specify the effect of progesterone on arterial endothelial cells in response to oxidative stress. Our result showed that H2O2 (150 µM and 300 µM) induced cellular antioxidant response. Glutathione (GSH) production and the activity of Glutathione peroxidase (GPx) were increased in H2O2-treated group. The expression of glutamate cysteine ligase catalytic subunit (GCLC) and modifier subunit (GCLM) was induced in response to H2O2. However, progesterone absolutely abolished the antioxidant response through increasing ROS level, inhibiting the activity of Glutathione peroxidase (GPx), decreasing GSH level and reducing expression of GClC and GCLM. In our study, H2O2 induced nitrogen monoxide (NO) production and endothelial nitric oxide synthase (eNOS) expression, and progesterone promoted H2O2-induced NO production. Progesterone increased H2O2-induced expression of hypoxia inducible factor-α (HIFα) which in turn regulated eNOS expression and NO synthesis. Further study demonstrated that progesterone increased H2O2 concentration of culture medium which may contribute to NO synthesis. Exogenous GSH decreased the content of H2O2 of culture medium pretreated by progesterone combined with H2O2 or progesterone alone. GSH also inhibited expression of HIFα and eNOS, and abolished NO synthesis. Collectively, our study demonstrated for the first time that progesterone inhibited cellular antioxidant effect and increased oxidative stress, promoted NO production of arterial endothelial cells, which may be due to the increasing H2O2 concentration and amplified oxidative stress signal.


Assuntos
Endotélio Vascular/citologia , Peróxido de Hidrogênio/metabolismo , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Progesterona/farmacologia , Animais , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Glutationa/metabolismo , Glutationa/farmacologia , Peróxido de Hidrogênio/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo III/metabolismo , Progesterona/metabolismo
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