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1.
Opt Express ; 32(2): 1295-1304, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297684

RESUMO

The combined application of metasurface and terahertz (THz) time-domain spectroscopy techniques has received considerable attention in the fields of sensing and detection. However, to detect trace samples, the THz wave must still be enhanced locally using certain methods to improve the detection sensitivity. In this study, we proposed and experimentally demonstrated a fano resonance metasurface-based silver nanoparticles (FaMs-AgNPs) sensor. AgNPs can enhance the sensitivity of the sensor by generating charge accumulation and inducing localized electric field enhancement through the tip effect, thereby enhancing the interaction between the THz waves and analytes. We investigated the effects of four different contents of AgNPs, 10 µl, 20 µl, 30 µl and 40 µl, on the detection of acetamiprid. At 30 µl of AgNPs, the amplitude change of the FaMs-AgNPs sensor was more pronounced and the sensitivity was higher, which could detect acetamiprid solutions as low as 100 pg/ml. The FaMs-AgNPs sensor has the advantages of a simple structure, easy processing, and excellent sensing performance, and has a great potential application value in the field of THz trace detection and other fields.

2.
J Environ Manage ; 344: 118497, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37413726

RESUMO

The heterogeneous Fenton-like systems induced by Fe-containing minerals have been largely applied for the degradation of organic pollutants. However, few studies have been conducted on biochar (BC) as an additive to Fenton-like systems mediated by iron-containing minerals. In this study, the addition of BC prepared at different temperatures was found to significantly enhance the degradation of contaminants in the tourmaline-mediated Fenton-like system (TM/H2O2) using Rhodamine B (RhB) as the target contaminant. Furthermore, the hydrochloric acid-modified BC prepared at 700 °C (BC700(HCl)) could achieve complete degradation of high concentrations of RhB in the BC700(HCl)/TM/H2O2 system. Free radical quenching experiments showed that TM/H2O2 system removed contaminants mainly mediated by the free radical pathway. After adding BC, the removal of contaminants is mainly mediated by the non-free radical pathway in BC700(HCl)/TM/H2O2 system which was confirmed by the Electron paramagnetic resonance (EPR) experiments and electrochemical impedance spectroscopy (EIS). In addition, BC700(HCl) had broad feasibility in the degradation of other organic pollutants (Methylene Blue (MB) 100%, Methyl Orange (MO) 100%, and tetracycline (TC) 91.47%) in the tourmaline-mediated Fenton-like system. Possible pathways for the degradation of RhB by the BC700(HCl)/TM/H2O2 system were also proposed.


Assuntos
Poluentes Ambientais , Peróxido de Hidrogênio , Peróxido de Hidrogênio/química , Minerais , Radicais Livres
3.
Opt Express ; 30(22): 40401-40412, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36298974

RESUMO

Terahertz logic gates play a vital role in optical signal processing and terahertz digitization. Herein, a strategy to design an all-optical terahertz logic gate device composed of metamaterials with a semiconductor-metal hybrid is proposed; accordingly, a concrete logic gate composed of Ge embedded-in Au stripe supported by a Si board is presented theoretically. Simulation results reveal the dependence of the terahertz transmission spectra on the different illuminations in the device. Based on the illumination-transmission response, the designed device can realize the NOR or OR Boolean operation. The effects of the width of the Ge-Au stripe as well as the Si board on the transmission spectra and logic performance were also investigated.

4.
Environ Sci Technol ; 56(15): 10656-10667, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35876052

RESUMO

Bacterial metal detoxification mechanisms have been well studied for centuries in pure culture systems. However, profiling metal resistance determinants at the community level is still a challenge due to the lack of comprehensive and reliable quantification tools. Here, a novel high-throughput quantitative polymerase chain reaction (HT-qPCR) chip, termed the metal resistance gene (MRG) chip, has been developed for the quantification of genes involved in the homeostasis of 9 metals. The MRG chip contains 77 newly designed degenerate primer sets and 9 published primer sets covering 56 metal resistance genes. Computational evaluation of the taxonomic coverage indicated that the MRG chip had a broad coverage matching 2 kingdoms, 29 phyla, 64 classes, 130 orders, 226 families, and 382 genera. Temperature gradient PCR and HT-qPCR verified that 57 °C was the optimal annealing temperature, with amplification efficiencies of over 94% primer sets achieving 80-110%, with R2 > 0.993. Both computational evaluation and the melting curve analysis of HT-qPCR validated a high specificity. The MRG chip has been successfully applied to characterize the distribution of diverse metal resistance determinants in natural and human-related environments, confirming its wide scope of application. Collectively, the MRG chip is a powerful and efficient high-throughput quantification tool for exploring the microbial metal resistome.


Assuntos
Bactérias , Metais Pesados , Bactérias/genética , Humanos , Reação em Cadeia da Polimerase em Tempo Real
5.
Ann Pharmacother ; 56(8): 888-897, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34749535

RESUMO

BACKGROUND: Valproic acid (VPA) has been widely used to prevent epileptic seizures after neurosurgery in China. We have found that the incidence of liver injury (LI) in patients using VPA after neurosurgery is higher than that in other patients. OBJECTIVE: The objective of this study was to investigate the risk factors of LI in patients using VPA after neurosurgery. METHODS: A nested case-control study was conducted in patients using VPA after neurosurgery between September 2019 and March 2021. Cases of LI were matched to controls by age and body mass index (BMI). Conditional logistic regression was used to estimate matched odds ratios representing the odds of LI. A receiver operating characteristic curve was used to analyze the optimal cutoff condition. RESULTS: A total of 248 people (62 LI and 186 control) were enrolled. Among patients with vs without LI, the matched odds ratio for trough concentration of VPA was significant (matched odds ratio [OR], 1.09; 95% confidence interval [CI]: 1.01-1.19). The course of treatment (OR: 1.17, 95% CI: 1.02-1.33), Glasgow score (OR: 0.26, 95% CI: 0.10-0.67), gene polymorphisms of CYP2C19 (OR: 2.09, 95% CI: 1.03-146.93), and UGT1A6 (OR: 34.61, 95% CI: 1.19-1003.23) were all related to the outcome. The optimal cutoff of the course of treatment was 10 days, while the trough concentration of VPA was determined to be 66.16 mg/L. CONCLUSION: Length of treatment, VPA trough concentration, and Glasgow score were associated with LI in patients after neurosurgery. A gene test may be necessary for people who are prescribed VPA for a long time.


Assuntos
Neurocirurgia , Ácido Valproico , Anticonvulsivantes/efeitos adversos , Estudos de Casos e Controles , Humanos , Fígado , Estudos Prospectivos , Ácido Valproico/efeitos adversos
6.
Environ Res ; 210: 112910, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35151659

RESUMO

The biorecovery of gold (Au) by microbial reduction has received increasing attention, however, the biomolecules involved and the mechanisms by which they operate to produce Au nanoparticles have been not resolved. Here we report that Burkholderia contaminans ZCC is capable of reduction of Au(III) to Au nanoparticles on the cell surface. Exposure of B. contaminans ZCC to Au(III) led to significant changes in the functional group of cell proteins, with approximately 11.1% of the (C-C/C-H) bonds being converted to CO (8.1%) and C-OH (3.0%) bonds and 29.4% of the CO bonds being converted to (C-OH/C-O-C/P-O-C) bonds, respectively. In response to Au(III), B. contaminans ZCC also displayed the ability of extracellular electron transfer (EET) via membrane proteins and could produce reduced riboflavin as verified by electrochemical and liquid chromatography-mass spectrometric results, but did not do so without Au(III) being present. Addition of exogenous reduced riboflavin to the medium suggested that B. contaminans ZCC could utilize indirect EET via riboflavin to enhance the rate of reduction of Au(III). Transcriptional analysis of the riboflavin genes (ribBDEFH) supported the view of the importance of riboflavin in the reduction of Au(III) and its importance in the biorecovery of gold.


Assuntos
Ouro , Nanopartículas Metálicas , Burkholderia , Elétrons , Riboflavina
7.
Int J Mol Sci ; 23(10)2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35628430

RESUMO

Arsenic (As), distributed widely in the natural environment, is a toxic substance which can severely impair the normal functions in living cells. Research on the genetic determinants conferring functions in arsenic resistance and metabolism is of great importance for remediating arsenic-contaminated environments. Many organisms, including bacteria, have developed various strategies to tolerate arsenic, by either detoxifying this harmful element or utilizing it for energy generation. More and more new arsenic resistance (ars) determinants have been identified to be conferring resistance to diverse arsenic compounds and encoded in ars operons. There is a hazard in mobilizing arsenic during gold-mining activities due to gold- and arsenic-bearing minerals coexisting. In this study, we isolated 8 gold enrichment strains from the Zijin gold and copper mine (Longyan, Fujian Province, China) wastewater treatment site soil, at an altitude of 192 m. We identified two Brevundimonas nasdae strains, Au-Bre29 and Au-Bre30, among these eight strains, having a high minimum inhibitory concentration (MIC) for As(III). These two strains contained the same ars operons but displayed differences regarding secretion of extra-polymeric substances (EPS) upon arsenite (As(III)) stress. B. nasdae Au-Bre29 contained one extra plasmid but without harboring any additional ars genes compared to B. nasdae Au-Bre30. We optimized the growth conditions for strains Au-Bre29 and Au-Bre30. Au-Bre30 was able to tolerate both a lower pH and slightly higher concentrations of NaCl. We also identified folE, a folate synthesis gene, in the ars operon of these two strains. In most organisms, folate synthesis begins with a FolE (GTP-Cyclohydrolase I)-type enzyme, and the corresponding gene is typically designated folE (in bacteria) or gch1 (in mammals). Heterologous expression of folE, cloned from B. nasdae Au-Bre30, in the arsenic-hypersensitive strain Escherichia coli AW3110, conferred resistance to As(III), arsenate (As(V)), trivalent roxarsone (Rox(III)), pentavalent roxarsone (Rox(V)), trivalent antimonite (Sb(III)), and pentavalent antimonate (Sb(V)), indicating that folate biosynthesis is a target of arsenite toxicity and increased production of folate confers increased resistance to oxyanions. Genes encoding Acr3 and ArsH were shown to confer resistance to As(III), Rox(III), Sb(III), and Sb(V), and ArsH also conferred resistance to As(V). Acr3 did not confer resistance to As(V) and Rox(V), while ArsH did not confer resistance to Rox(V).


Assuntos
Arsênio , Arsenitos , Caulobacteraceae , Roxarsona , Arsênio/metabolismo , Arsenitos/toxicidade , Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Caulobacteraceae/metabolismo , Escherichia coli/metabolismo , Ácido Fólico/metabolismo , Ouro/metabolismo , Roxarsona/metabolismo , Roxarsona/farmacologia
8.
Appl Environ Microbiol ; 87(24): e0158821, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34613763

RESUMO

In this study, comprehensive analyses were performed to determine the function of an atypical MarR homolog in Achromobacter sp. strain As-55. Genomic analyses of Achromobacter sp. As-55 showed that this marR is located adjacent to an arsV gene. ArsV is a flavin-dependent monooxygenase that confers resistance to the antibiotic methylarsenite [MAs(III)], the organoarsenic compound roxarsone(III) [Rox(III)], and the inorganic antimonite [Sb(III)]. Similar marR genes are widely distributed in arsenic-resistant bacteria. Phylogenetic analyses showed that these MarRs are found in operons predicted to be involved in resistance to inorganic and organic arsenic species, so the subfamily was named MarRars. MarRars orthologs have three conserved cysteine residues, which are Cys36, Cys37, and Cys157 in Achromobacter sp. As-55, mutation of which compromises the response to MAs(III)/Sb(III). GFP-fluorescent biosensor assays show that AdMarRars (MarR protein of Achromobacter deleyi As-55) responds to trivalent As(III) and Sb(III) but not to pentavalent As(V) or Sb(V). The results of RT-qPCR assays show that arsV is expressed constitutively in a marR deletion mutant, indicating that marR represses transcription of arsV. Moreover, electrophoretic mobility shift assays (EMSAs) demonstrate that AdMarRars binds to the promoters of both marR and arsV in the absence of ligands and that DNA binding is relieved upon binding of As(III) and Sb(III). Our results demonstrate that AdMarRars is a novel As(III)/Sb(III)-responsive transcriptional repressor that controls expression of arsV, which confers resistance to MAs(III), Rox(III), and Sb(III). AdMarRars and its orthologs form a subfamily of MarR proteins that regulate genes conferring resistance to arsenic-containing antibiotics. IMPORTANCE In this study, a MarR family member, AdMarRars was shown to regulate the arsV gene, which confers resistance to arsenic-containing antibiotics. It is a founding member of a distinct subfamily that we refer to as MarRars, regulating genes conferring resistance to arsenic and antimony antibiotic compounds. AdMarRars was shown to be a repressor containing conserved cysteine residues that are required to bind As(III) and Sb(III), leading to a conformational change and subsequent derepression. Here we show that members of the MarR family are involved in regulating arsenic-containing compounds.


Assuntos
Achromobacter/genética , Arsênio , Arsenicais , Genes Bacterianos , Achromobacter/efeitos dos fármacos , Antibacterianos , Arsênio/farmacologia , Arsenicais/farmacologia , Cisteína , Farmacorresistência Bacteriana , Família Multigênica , Filogenia , Roxarsona/farmacologia
9.
Ecotoxicol Environ Saf ; 211: 111914, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33454593

RESUMO

Bioremediation of Cd contaminated environments can be assisted by plant-growth-promoting bacteria (PGPB) enabling plant growth in these sites. Here a gram-negative Burkholderia contaminans ZCC was isolated from mining soil at a copper-gold mine. When exposed to Cd(II), ZCC displayed high Cd resistance and the minimal inhibitory concentration was 7 mM in LB medium. Complete genome analysis uncovered B. contaminans ZCC contained 3 chromosomes and 2 plasmids. One of these plasmids was shown to contain a multitude of heavy metal resistance determinants including genes encoding a putative Cd-translocating PIB-type ATPase and an RND-type related to the Czc-system. These additional heavy metal resistance determinants are likely responsible for the increased resistance to Cd(II) and other heavy metals in comparison to other strains of B. contaminans. B. contaminans ZCC also displayed PGPB traits such as 1-aminocyclopropane-1-carboxylate deaminase activity, siderophore production, organic and inorganic phosphate solubilization and indole acetic acid production. Moreover, the properties and Cd(II) binding characteristics of extracellular polymeric substances was investigated. ZCC was able to induce extracellular polymeric substances production in response to Cd and was shown to be chemically coordinated to Cd(II). It could promote the growth of soybean in the presence of elevated concentrations of Cd(II). This work will help to better understand processes important in bioremediation of Cd-contaminated environment.


Assuntos
Adaptação Fisiológica/fisiologia , Burkholderia/fisiologia , Cádmio/toxicidade , Poluentes do Solo/toxicidade , Biodegradação Ambiental , Cádmio/metabolismo , Ácidos Indolacéticos , Metais Pesados/análise , Mineração , Desenvolvimento Vegetal , Solo/química , Microbiologia do Solo , Poluentes do Solo/análise , Glycine max/metabolismo
10.
Lupus ; 29(8): 854-861, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32437257

RESUMO

OBJECTIVE: Lupus nephritis (LN) is one of the serious complications of systemic lupus erythematosus. The aim of this study was to identify core genes and pathways involved in the pathogenesis of LN. METHODS: We screened differentially expressed genes (DEGs) in LN patients using mRNA expression profile data from the Gene Expression Omnibus. The functional and pathway enrichment analysis of DEGs was performed utilizing the Database for annotation, Visualization and Integrated Discovery. Target genes with differentially expressed miRNAs (DEMIs) were predicted using the miRTarBase database, and the intersection between these target genes and DEGs was selected to be studied further. RESULTS: In total, 107 common DEGs (CDEGs) were identified from the Tub_LN group and Glom_LN group, and 66 DEMIs were identified. Fifty-three hub genes and two significant modules were identified from the protein-protein interaction (PPI) network, and a miRNA-mRNA network was constructed. The CDEGs, module genes in the PPI network and genes intersecting with the CDEGs and target genes of DEMIs were all associated with the PI3K-Akt signalling pathway. CONCLUSION: In summary, this study reveals some crucial genes and pathways potentially involving in the pathogenesis of LN. These findings provide a new insight for the research and treatment of LN.


Assuntos
Nefrite Lúpica/metabolismo , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Biologia Computacional , Expressão Gênica , Redes Reguladoras de Genes , Humanos , Nefrite Lúpica/genética , Mapas de Interação de Proteínas , Transdução de Sinais
11.
Ecotoxicol Environ Saf ; 206: 111229, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32889310

RESUMO

Arsenite is the predominant arsenic species in flooded paddy soil, and arsenite bioaccumulation in rice grains has been identified as a major problem in many Asian countries. Lowering arsenite level in rice plants and grain via accelerating arsenite oxidation is a potential strategy to help populations, who depended on rice consumption, to reduce the internal exposure level of arsenic. We herein isolated a strain, Achromobacter xylosoxidans GD03, with the high arsenite-oxidizing ability and plant growth-promoting traits. We observed that arsenite exposure could promote A. xylosoxidans GD03 to excrete indole-3-acetic acid and thus promoted rice growth. The pot culture experiments of Indica rice cultivar Guang You Ming 118 (GYM118) demonstrated that A. xylosoxidans GD03 inoculation of paddy soil (4.5-180 × 108 CFU GD03/kg soil) significantly accelerated arsenite oxidation in flooded soil. The daily arsenic oxidation rate with GD03 inoculation was 1.5-3.3 times as that without strain GD03 inoculation within the whole growth period of Indica GYM118 in the presence of the native microflora. It thus led to a 34-69%, 43-74%, 24-76% and 35-57% decrease in arsenite concentration of the stems, leaves, bran and grain of Indica GYM118 respectively and a 59-96% increase in rice grain yield. The paddy soil inoculated with 40.0 mL/kg of A. xylosoxidans GD03 resulted in a lowest As(III) concentrations in all rice organs of Indica GYM118, which equivalent to only 24-50% of the As(III) concentrations in the group without GD03 inoculation. The results highlight that a highly arsenite-oxidizing bacterium could accelerate arsenite oxidation of paddy soil when facing competition with the native microflora, thus decrease arsenic toxicity and bioavailable soil arsenic.


Assuntos
Achromobacter denitrificans/crescimento & desenvolvimento , Arsenitos/metabolismo , Bioacumulação , Grão Comestível/crescimento & desenvolvimento , Oryza/crescimento & desenvolvimento , Poluentes do Solo/metabolismo , Achromobacter denitrificans/metabolismo , Arsenitos/análise , Ásia , Biomassa , Grão Comestível/metabolismo , Inundações , Oryza/metabolismo , Oryza/microbiologia , Oxirredução , Solo/química , Poluentes do Solo/análise
12.
Ecotoxicol Environ Saf ; 184: 109593, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31479760

RESUMO

Leaf vegetables have strong capabilities to take up cadmium (Cd) compared to other vegetable varieties. Until now, the differences in Cd uptake and accumulation by leaf vegetables from different families and genera and the related health risks were unknown. To remedy this, we studied 71 leaf vegetables (multiple genotypes within 17 categories of vegetables) in soil cultivation experiments (3 Cd treatment levels). Results showed that at 2.12 mg kg-1 Cd treatment, the dry weight of only five genotypic varieties from the families Brassicaceae and Asteraceae significantly decreased compared to the control, suggesting their weak Cd tolerances. Vegetables from the Brassicaceae, Asteraceae, Apiaceae, and Convolvulaceae families had stronger Cd absorption capabilities, whereas those from the Liliaceae and Amaranthaceae families had weaker ones. Cluster analysis found that the 17 vegetable categories could be divided into three groups: vegetables with high Cd accumulation capabilities were Lactuca sativa L.var. ramosa Hort. and Lactuca sativa var. longifoliaf. Lam. Vegetables with moderate Cd accumulation capabilities were bok choy, napa cabbage, choy sum, leaf mustard, Lactuca sativa L., Sonchus oleraceus L., celery, coriander, and water spinach. Vegetables with low Cd accumulation capabilities were cabbage, crown daisy, garlic chive, Allium ascalonicum, Gynura cusimbua, and edible amaranth. Estimated daily intake (EDI) and target hazard quotient (THQ) analysis results showed that 100% genotypes of vegetables from the Apiaceae and Convolvulaceae families had health risks; 100% genotypes of Lactuca sativa L., Sonchus oleraceus L., Lactuca sativa L. var. ramosa Hort., and Lactuca sativa var. longifoliaf. Lam from the Asteraceae family carried high risks. Of vegetables in the Brassicaceae family, 42.9% showed risks. Vegetables from the Amaranthaceae and Liliaceae families, Gynura cusimbua and crown daisy from the Asteraceae family, and cabbage from the Brassicaceae family all displayed relatively low risks (all 100%).


Assuntos
Cádmio/metabolismo , Contaminação de Alimentos , Poluentes do Solo/metabolismo , Verduras/metabolismo , Cádmio/análise , Cádmio/toxicidade , Humanos , Folhas de Planta/classificação , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Medição de Risco , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Especificidade da Espécie , Estresse Fisiológico/efeitos dos fármacos , Verduras/classificação , Verduras/efeitos dos fármacos
13.
Appl Microbiol Biotechnol ; 100(22): 9709-9718, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27576494

RESUMO

This paper studied the degradation of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) in contaminated soil under composting and natural conditions, respectively. BDE-47 residue in agricultural waste-composting pile was determined during 45-day composting. The microbial communities were determined by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), and the relationships between the DGGE results and physico-chemical parameters were evaluated by redundancy analysis (RDA) and heatmap-clustering analysis. The results showed that the degradation rate of BDE-47 was significantly higher in agricultural waste-composting pile compared with control group, which was enhanced up to almost 15 % at the end of composting. There were different environmental factors which affected the distribution of composting bacterial and fungal communities. The bacterial community composition was more significantly affected by the addition of BDE-47 compared with other physico-chemical parameters, and BDE-47 had stronger influences on bacterial community than fungal community during the composting. Meanwhile, the most variation in distribution of fungal community was explained by pile temperature.


Assuntos
Biota/efeitos dos fármacos , Éteres Difenil Halogenados/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Solo , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Biodegradação Ambiental , Eletroforese em Gel de Gradiente Desnaturante , Fungos/classificação , Fungos/efeitos dos fármacos , Fungos/genética , Reação em Cadeia da Polimerase , Temperatura
14.
J Asian Nat Prod Res ; 18(4): 334-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26666377

RESUMO

Two new homoisoflavans, 4'-hydroxy-7-methoxy-3-benzyl-2H-chromene (1) and 3,4-cis-di-O-3-hydroxy-7-methoxy-3-(4-hydroxybenzyl)-4-ethoxychroman (2), one new coumarin, 7-methoxy-3-(4-hydroxybenzyl)coumarin (4), together with seven known phenolic compounds, bonducellin (3), anemarcoumarin A (5), (+)-syringaresinol (6), curuilignan D (7), scopoletin (8), and p-hydroxybenzaldehyde (9), were isolated from Tara (Caesalpinia spinosa Kuntze). The structures of the new compounds were characterized from their 1D and 2D NMR spectral data. All the compounds were isolated from this plant for the first time.


Assuntos
Caesalpinia/química , Fenóis/isolamento & purificação , Benzopiranos , Cumarínicos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Fenóis/química , Folhas de Planta/química
15.
Appl Microbiol Biotechnol ; 98(9): 4233-43, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24442505

RESUMO

The purpose of this study was to investigate the diversity of denitrifier community during agricultural waste composting. The diversity and dynamics of the denitrifying genes (nirK and nirS) were determined using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Relationships between physico-chemical parameters and denitrifying genes structures were simultaneously evaluated by redundancy analysis (RDA). Phylogenetic analysis indicated that nirK clones grouped into six clusters and nirS clones into two major clusters, respectively. The results showed a very high diversity of nir gene sequences within composting samples. RDA showed that the nirK and nirS gene structures were significantly related to pH and pile temperature (P < 0.05). Significant amounts of the variation (49.2 and 38.3 % for nirK and nirS genes, respectively) were explained by pH and pile temperature, suggesting that those two parameters were the most likely ones to influence, or be influenced by the denitrifiers harboring nirK and nirS genes.


Assuntos
Agricultura/métodos , Bactérias/metabolismo , Biodiversidade , Desnitrificação , Eliminação de Resíduos de Serviços de Saúde/métodos , Nitrito Redutases/análise , Microbiologia do Solo , Bactérias/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , Eletroforese em Gel de Gradiente Desnaturante , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Nitrito Redutases/genética , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Homologia de Sequência , Temperatura
16.
Psych J ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530882

RESUMO

While seeking advice can be beneficial for advisees, advisors may not always possess the necessary knowledge to provide appropriate guidance. Poor-quality advice can mislead advisees rather than offering assistance. Despite the research interest in advisees, few studies have investigated advisors' psychological and behavioral responses, especially when they faced uncertainty regarding the optimal course of action for advisees. To fill this gap, we developed novel paradigms aiming at manipulating advisors' uncertainty, allowing for a systematic investigation of advisors' behavior, motivation, and emotion. Across four studies, we consistently found that advisors under uncertainty give less advice. Furthermore, we observed that uncertainty modulates advisors' motivation to influence, worry about harm to others, and/or sense of power. The motivation to influence and/or worry about harm to others can mediate the effect of uncertainty on advice giving. Besides, we identified nuanced distinctions in the effects of ambiguity and risk, two distinct types of uncertainty, on advisors' psychological processes. Our findings shed light on advisors' self-monitoring of the quality of their advice, thereby contributing to a deeper understanding of advisor-advisee communication from the perspective of advisors.

17.
Trends Microbiol ; 32(5): 465-476, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38103995

RESUMO

Metals and metalloids are used as weapons for predatory feeding by unicellular eukaryotes on prokaryotes. This review emphasizes the role of metal(loid) bioavailability over the course of Earth's history, coupled with eukaryogenesis and the evolution of the mitochondrion to trace the emergence and use of the metal(loid) prey-killing phagosome as a feeding strategy. Members of the genera Acanthamoeba and Dictyostelium use metals such as zinc (Zn) and copper (Cu), and possibly metalloids, to kill their bacterial prey after phagocytosis. We provide a potential timeline on when these capacities first evolved and how they correlate with perceived changes in metal(loid) bioavailability through Earth's history. The origin of phagotrophic eukaryotes must have postdated the Great Oxidation Event (GOE) in agreement with redox-dependent modification of metal(loid) bioavailability for phagotrophic poisoning. However, this predatory mechanism is predicted to have evolved much later - closer to the origin of the multicellular metazoans and the evolutionary development of the immune systems.


Assuntos
Dictyostelium , Metais , Fagocitose , Metais/metabolismo , Dictyostelium/metabolismo , Dictyostelium/fisiologia , Evolução Biológica , Acanthamoeba , Animais , Fagossomos/metabolismo , Zinco/metabolismo , Metaloides/metabolismo , Cobre/metabolismo , Disponibilidade Biológica , Mitocôndrias/metabolismo
18.
Sci Total Environ ; 924: 171600, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38461986

RESUMO

The electric field-assisted composting system (EACS) is an emerging technology that can enhance composting efficiency, but little attention has been given to electrode materials. Herein, an EACS was established to investigate the effects of electrode materials on humic substance formation and heavy metal speciation. Excitation-emission matrix analysis showed that carbon-felt and stainless-steel electrodes increased humic acid (HA) by 48.57 % and 47.53 %, respectively. In the EACS with the carbon-felt electrode, the bioavailability factors (BF) of Cu and Cr decreased by 18.00 % and 7.61 %, respectively. Despite that the stainless-steel electrodes decreased the BF of As by 11.26 %, the leaching of Cr, Ni, Cu, and Fe from the electrode itself is an inevitable concern. Microbial community analyses indicated that the electric field increased the abundance of Actinobacteria and stimulated the multiplication of heavy metal-tolerant bacteria. Redundancy analysis indicates that OM, pH, and current significantly affect the evolution of heavy metal speciation in the EACS. This study first evaluated the metal leaching risk of stainless-steel electrode, and confirmed that carbon-felt electrode is environment-friendly material with high performance and low risk in future research with EACS.


Assuntos
Compostagem , Metais Pesados , Solo/química , Metais Pesados/análise , Substâncias Húmicas/análise , Aço Inoxidável , Bactérias , Carbono
19.
Sci Total Environ ; 920: 170803, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38342448

RESUMO

Novel tourmaline-biochar composites (TBs) were synthesized by introducing tourmaline (TM) into pomelo peel biochar (BC). The surface properties of TBs and BC were studied and the adsorption performances for Pb2+ were investigated. Compared to pristine BC, the adsorption ability for Pb2+ on TBs was enhanced with the increase of TM in TBs, and up to 514.62 mg/g on 5%TB. The enrichment of inorganic metals caused by TM in TBs made the precipitation and cation ion exchange become the main mechanisms in adsorbing Pb2+, and the amounts of adsorbing Pb2+ by those two mechanisms on TBs were 1.10-1.48 times and 1.20-1.30 times those of BC, respectively. Furthermore, applying TBs to practical contaminated soil increased the soil pH and electrical conductivity (EC) after 15 days of incubation. The increased content of residual-Pb and reduced exchangeable-Pb and DTPA-Pb indicated that TBs were favorable for the immobilization of Pb in soil. This study gives a new perspective on the synthesis of tourmaline-biochar composite and their application in Pb-polluted water and soil.

20.
Neurol Ther ; 12(1): 197-209, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36401149

RESUMO

INTRODUCTION: This study aimed to investigate the relationship between gene polymorphisms and clinical factors with the concentrations of valproic acid (VPA) in adult patients who underwent neurosurgery in China. METHODS: A total of 531 serum concentration samples at steady state were collected from 313 patients to develop a population pharmacokinetic (PPK) model. Data analysis was performed using nonlinear mixed effects modeling. Covariates included demographic parameters, biological characteristics, and genetic polymorphism. Bootstrap evaluation showed that the final model was stable. Sensitive analysis was performed to verify the relationship between gene polymorphisms and concentrations of VPA. Linear regression was used to analyze the relationship between VPA concentration, ANKK1, and daily dosage. RESULTS: In the recruited patients, 17 of 25 single-nucleotide polymorphism distributions were consistent with the Hardy-Weinberg equilibrium. A one-compartment model with first-order absorption and elimination was developed for VPA injections. VPA clearance was significantly influenced by three variables: sex (17.41% higher in male than female patients), body weight, and the ANKK1 gene. Typical values for the elimination clearance and the volume of central compartment were 0.614 L/min and 23.5 L, respectively. The model evaluation indicated the stable and precise performance of the final model. After sensitive analysis using Kruskal-Wallis and Mann-Whitney U tests, we found that patients with AA alleles had higher VPA concentrations than those with GG and AG alleles. Linear regression models showed that gene polymorphisms of ANKK1 had little effects on VPA concentration. CONCLUSION: A PPK model of VPA in Chinese Han patients was successfully established; this can be helpful for model-informed precision-dosing approaches in clinical patient care, and for exploring the mechanism of VPA-induced weight gain.

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