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1.
J Immunol ; 208(6): 1424-1433, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35197329

RESUMO

NF-erythroid 2-related factor 2 (Nrf2) is a major transcription factor to protect cells against reactive oxygen species (ROS) and reactive toxicants. Meanwhile, Nrf2 can inhibit contact dermatitis through redox-dependent and -independent pathways. However, the underlying mechanisms of how Nrf2 mediates irritant contact dermatitis (ICD) are still unclear. In this article, we elucidated the role of Nrf2 in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced acute ICD. Our study demonstrated that the ear thickness, redness, swelling, and neutrophil infiltration were significantly increased, accompanied by increased expression of inflammatory cytokines (IL-1α, IL-1ß, IL-6, etc.) and decreased expression of antioxidant genes (HO-1 and NQO1) in Nrf2 knockout mice. Moreover, ERK phosphorylation was elevated in mouse embryonic fibroblasts (MEFs) from Nrf2 knockout mouse. Inhibition of ERK significantly alleviated TPA-induced cutaneous inflammation and ROS accumulation in MEFs derived from mouse. Conversely, ROS scavenging inhibited the ERK activation and TPA-induced inflammation in MEFs. Taken together, the findings illustrate the key role of the Nrf2/ROS/ERK signaling pathway in TPA-induced acute ICD.


Assuntos
Dermatite de Contato , Fator 2 Relacionado a NF-E2 , Animais , Camundongos , Fibroblastos/metabolismo , Heme Oxigenase-1/metabolismo , Inflamação , Irritantes , Camundongos Knockout , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Acetato de Tetradecanoilforbol
2.
Luminescence ; 39(7): e4827, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39048529

RESUMO

Chemiluminescence resonance energy transfer (CRET) efficiency can be enhanced by confining CRET donors and acceptors within nanoscale spaces. However, this enhanced efficiency is often affected by uncertainties stemming from the random distribution of CRET donors and acceptors in such confined environments. In this study, a novel confined nanospace was created through the surfactant modification of carbon dots (CDs) exhibiting aggregation-induced emission (AIE) characteristics. Hydrophobic CRET donors could be effectively confined within this nanospace. The distance between the CRET donors and acceptors could be controlled by anchoring the AIE-CDs as the CRET acceptors, resulting in significantly improved CRET efficiency. Furthermore, this AIE-CDs-based CRET system was successfully applied to the detection of hydrogen peroxide (H2O2) in rainwater, showcasing its potential for practical applications.


Assuntos
Carbono , Peróxido de Hidrogênio , Luminescência , Pontos Quânticos , Tensoativos , Carbono/química , Tensoativos/química , Pontos Quânticos/química , Peróxido de Hidrogênio/química , Medições Luminescentes , Transferência Ressonante de Energia de Fluorescência , Transferência de Energia
3.
Brief Bioinform ; 22(4)2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-33079984

RESUMO

OBJECTIVE: We aimed to identify key susceptibility gene targets in multiple datasets generated from postmortem brains and blood of Parkinson's disease (PD) patients and healthy controls (HC). METHODS: We performed a multitiered analysis to integrate the gene expression data using multiple-gene chips from 244 human postmortem tissues. We identified hub node genes in the highly PD-related consensus module by constructing protein-protein interaction (PPI) networks. Next, we validated the top four interacting genes in 238 subjects (90 sporadic PD, 125 HC and 23 Parkinson's Plus Syndrome (PPS)). Utilizing multinomial logistic regression analysis (MLRA) and receiver operating characteristic (ROC), we analyzed the risk factors and diagnostic power for discriminating PD from HC and PPS. RESULTS: We identified 1333 genes that were significantly different between PD and HCs based on seven microarray datasets. The identified MEturquoise module is related to synaptic vesicle trafficking (SVT) dysfunction in PD (P < 0.05), and PPI analysis revealed that SVT genes PPP2CA, SYNJ1, NSF and PPP3CB were the top four hub node genes in MEturquoise (P < 0.001). The levels of these four genes in PD postmortem brains were lower than those in HC brains. We found lower blood levels of PPP2CA, SYNJ1 and NSF in PD compared with HC, and lower SYNJ1 in PD compared with PPS (P < 0.05). SYNJ1, negatively correlated to PD severity, displayed an excellent power to discriminating PD from HC and PPS. CONCLUSIONS: This study highlights that SVT genes, especially SYNJ1, may be promising markers in discriminating PD from HCs and PPS.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Proteínas do Tecido Nervoso , Doença de Parkinson , Mapas de Interação de Proteínas , Vesículas Sinápticas , Autopsia , Biomarcadores/metabolismo , Feminino , Humanos , Masculino , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Vesículas Sinápticas/genética , Vesículas Sinápticas/metabolismo
4.
Arch Microbiol ; 205(3): 89, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36781495

RESUMO

The spreading of antimicrobial resistance (AMR) in crops and food products represents a global concern. In this study, we conducted a survey of resistomes in maize rhizosphere from Michigan, California, the Netherlands, and South Africa, and investigated potential associations with host bacteria and soil management practices in the crop field. For comparison, relative abundance of antibiotic resistance genes (ARGs) is normalized to the size of individual metagenomes. Michigan maize rhizosphere metagenomes showed the highest abundance and diversity of ARGs, with the detection of blaTEM-116, blaACT-4/-6, and FosA2, exhibiting high similarity (≥ 99.0%) to those in animal and human pathogens. This was probably related to the decade-long application of manure/composted manure from antibiotic-treated animals. Moreover, RbpA, vanRO, mtrA, and dfrB were prevalently found across most studied regions, implying their intrinsic origins. Further analysis revealed that RbpA, vanRO, and mtrA are mainly harbored by native Actinobacteria with low mobility since mobile genetic elements were rarely found in their flanking regions. Notably, a group of dfrB genes are adjacent to the recombination binding sites (attC), which together constitute mobile gene cassettes, promoting the transmission from soil bacteria to human pathogens. These results suggest that maize rhizosphere resistomes can be distinctive and affected by many factors, particularly those relevant to agricultural practices.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Zea mays , Animais , Humanos , Antibacterianos/farmacologia , Antibacterianos/análise , Bactérias/genética , Genes Bacterianos , Esterco/análise , Rizosfera , Solo/química , Microbiologia do Solo , Zea mays/genética , Farmacorresistência Bacteriana/genética
5.
Eur Radiol ; 33(12): 9109-9119, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37438642

RESUMO

OBJECTIVES: Using diffusion basis spectrum imaging (DBSI) to examine the microstructural changes in the substantia nigra (SN) and global white matter (WM) tracts of patients with early-stage PD. METHODS: Thirty-seven age- and sex-matched patients with early-stage PD and 22 healthy controls (HCs) were enrolled in this study. All participants underwent clinical assessments and diffusion-weighted MRI scans, analyzed by diffusion tensor imaging (DTI) and DBSI to assess the pathologies of PD in SN and global WM tracts. RESULTS: The lower DTI fraction anisotropy (FA) was seen in SN of PD patients (PD: 0.316 ± 0.034 vs HCs: 0.331 ± 0.019, p = 0.015). The putative cells marker-DBSI-restricted fraction (PD: 0.132 ± 0.051 vs HCs: 0.105 ± 0.039, p = 0.031) and the edema/extracellular space marker-DBSI non-restricted-fraction (PD: 0.150 ± 0.052 vs HCs: 0.122 ± 0.052, p = 0.020) were both significantly higher and the density of axons/dendrites marker-DBSI fiber-fraction (PD: 0.718 ± 0.073 vs HCs: 0.773 ± 0.071, p = 0.003) was significantly lower in SN of PD patients. DBSI-restricted fraction in SN was negatively correlated with HAMA scores (r = - 0.501, p = 0.005), whereas DTI-FA was not correlated with any clinical scales. In WM tracts, only higher DTI axial diffusivity (AD) among DTI metrics was found in multiple WM regions in PD, while lower DBSI fiber-fraction and higher DBSI non-restricted-fraction were detected in multiple WM regions. DBSI non-restricted-fraction in both left fornix (cres)/stria terminalis (r = -0.472, p = 0.004) and right posterior thalamic radiation (r = - 0.467, p = 0.005) was negatively correlated with MMSE scores. CONCLUSION: DBSI could potentially detect and quantify the extent of inflammatory cell infiltration, fiber/dendrite loss, and edema in both SN and WM tracts in patients with early-stage PD, a finding remains to be further investigated through more extensive longitudinal DBSI analysis. CLINICAL RELEVANCE STATEMENT: Our study shows that DBSI indexes can potentially detect early-stage PD's pathological changes, with a notable ability to distinguish between inflammation and edema. This implies that DBSI has the potential to be an imaging biomarker for early PD diagnosis. KEY POINTS: • Diffusion basis spectrum imaging detected higher restricted-fraction in Parkinson's disease, potentially reflecting inflammatory cell infiltration. • Diffusion basis spectrum imaging detected higher non-restricted-fraction and lower fiber-fraction in Parkinson's disease, indicating the presence of edema and/or dopaminergic neuronal/dendritic loss. • Diffusion basis spectrum imaging metrics correlated with non-motor symptoms, suggesting its potential diagnostic role to detect early-stage PD dysfunctions.


Assuntos
Doença de Parkinson , Substância Branca , Humanos , Imagem de Tensor de Difusão/métodos , Substância Branca/patologia , Doença de Parkinson/patologia , Substância Negra/diagnóstico por imagem , Substância Negra/patologia , Edema/patologia
6.
Angew Chem Int Ed Engl ; 62(52): e202314537, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37966039

RESUMO

In nature and technologies, many chemical reactions occur at interfaces with dimensions approaching that of a single reacting species in nano- and angstrom-scale. Mechanisms governing reactions at this ultimately small spatial regime remain poorly explored because of challenges to controllably fabricate required devices and assess their performance in experiment. Here we report how efficiency of electrochemical reactions evolves for electrodes that range from just one atom in thickness to sizes comparable with and exceeding hydration diameters of reactant species. The electrodes are made by encapsulating graphene and its multilayers within insulating crystals so that only graphene edges remain exposed and partake in reactions. We find that limiting current densities characterizing electrochemical reactions exhibit a pronounced size effect if reactant's hydration diameter becomes commensurable with electrodes' thickness. An unexpected blockade effect is further revealed from electrodes smaller than reactants, where incoming reactants are blocked by those adsorbed temporarily at the atomically narrow interfaces. The demonstrated angstrom-scale electrochemistry offers a venue for studies of interfacial behaviors at the true molecular scale.

7.
Fish Shellfish Immunol ; 131: 999-1005, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36195269

RESUMO

Intestinal enteritis is a main issue in crucian carp production which results in massive economic loss. Traditional antibiotics used for disease prevention of crucian carp (Carassius carassius) have been banned, thus an alternative approach needs to be identified. In this study, the bioactive peptide was evaluated as a diet supplement for preventing intestinal inflammation in crucian carp. Intestinal inflammation was induced by intrarectal administration of a 2,4,6-trinitrobenzene sulfonic acid (TNBS) solution. The fish samples were fed with different diets for 14 days. The disease activity index (DAI), which included, fish swimming, food intake, anal inflammation, body surface, and ascites was determined daily. Intestine segments were stained with haematoxylin and eosin (H.E.) for histopathological analysis. The expression of cytokines, including interleukin-1ß (IL-1ß), interleukin-8 (IL-8), tumor necrosis factor α (TNF-α), and myeloperoxidase (MPO) in crucian carp were determined. In TNBS-induced groups, the DAI scores were dramatically increased compared to the control group. The histopathological analysis showed that the damage of the fish intestine after the injection of TNBS. The relative expression levels of pro-inflammation cytokines (TNF-α, IL-1ß, IL-8, MPO) were significantly increased compared to the control group on day 1. In the TNBS-induced group feed with a diet supplemented with bioactive peptide, the symptoms of intestinal inflammation were relieved on day 3 and the mRNA expression levels of pro-inflammation cytokines (TNF-α, IL-1ß, IL-8, MPO) were reduced compared to day 1. On day 7, the fish samples enrofloxacin group and bioactive peptide group were recovered from TNBS-induced intestinal inflammation. This study showed that the fish diet supplemented with bioactive peptide could help to prevent and recover from intestinal inflammation. Thus, the bioactive peptide can be used as a replacement for antibiotics to prevent disease in aquaculture production.


Assuntos
Carpas , Animais , Ácido Trinitrobenzenossulfônico , Carpas/metabolismo , Interleucina-8 , Fator de Necrose Tumoral alfa/metabolismo , Citocinas/genética , Inflamação/induzido quimicamente , Inflamação/prevenção & controle , Inflamação/veterinária , Administração Oral , Antibacterianos
8.
Environ Sci Technol ; 56(3): 2033-2043, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35006678

RESUMO

Biological nitrogen fixation (BNF) has important environmental implications in tailings by providing bioavailable nitrogen to these habitats and sustaining ecosystem functions. Previously, chemolithotrophic diazotrophs that dominate in mine tailings were shown to use reduced sulfur (S) as the electron donor. Tailings often contain high concentrations of As(III) that might function as an alternative electron donor to fuel BNF. Here, we tested this hypothesis and report on BNF fueled by As(III) oxidation as a novel biogeochemical process in addition to BNF fueled by S. Arsenic (As)-dependent BNF was detected in cultures inoculated from As-rich tailing samples derived from the Xikuangshan mining area in China, as suggested by nitrogenase activity assays, quantitative polymerase chain reaction, and 15N2 enrichment incubations. As-dependent BNF was also active in eight other As-contaminated tailings and soils, suggesting that the potential for As-dependent BNF may be widespread in As-rich habitats. DNA-stable isotope probing identified Serratia spp. as the bacteria responsible for As-dependent BNF. Metagenomic binning indicated that the essential genes for As-dependent BNF [i.e., nitrogen fixation, As(III) oxidation, and carbon fixation] were present in Serratia-associated metagenome-assembled genomes. Over 20 Serratia genomes obtained from NCBI also contained essential genes for both As(III) oxidation and BNF (i.e., aioA and nifH), suggesting that As-dependent BNF may be a widespread metabolic trait in Serratia spp.


Assuntos
Arsênio , Fixação de Nitrogênio , Ecossistema , Nitrogênio/análise , Serratia/genética , Serratia/metabolismo , Microbiologia do Solo
9.
Curr Microbiol ; 79(5): 126, 2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35278139

RESUMO

The YMR253C open reading frame encodes a membrane protein that is highly expressed in NaCl-resistant Saccharomyces cerevisiae mutants. Whether it mediates NaCl tolerance is unclear. By knocking out YMR253C in S. cerevisiae, we found that the salt tolerance of yeast was reduced, the integrity of the cell wall was impaired, and cell death was induced; transcriptome analysis further revealed that YMR253C gene knockout mediates significant changes of 1291 genes, and YMR253C mediates the regulation of MAPK signal pathways. Therefore, the transmembrane protein YMR253C may regulate the MAPK signaling pathway to regulate the salt stress of S. cerevisiae.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Perfilação da Expressão Gênica , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Tolerância ao Sal/genética , Transdução de Sinais
10.
J Basic Microbiol ; 62(8): 930-936, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35689329

RESUMO

The YJL218W open reading frame may be involved in peroxisomal biogenesis. However, whether it mediates salt tolerance is unclear. We found that after knockdown of YJL218W in Saccharomyces cerevisiae (S. cerevisiae), its salt tolerance was reduced and cell death was increased. Transcriptome sequencing and analysis further revealed that YJL218W knockdown mediated significant changes in the expression of 1432 messenger RNA (mRNAs), of which 603 were upregulated. KEGG enrichment analysis and polymerase chain reaction (PCR) assay indicated that YJL218W mediated the regulation of peroxisome-related genes. Therefore, YJL218W may regulate salt stress in S. cerevisiae by regulating peroxisome assembly.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Peroxissomos/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Tolerância ao Sal/genética
11.
Eur J Neurol ; 28(4): 1265-1274, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33277774

RESUMO

BACKGROUND AND PURPOSE: The aim of this study was to explore whether cystatin C (CysC) could be used as a potential predictor of clinical outcomes in acute ischemic stroke (AIS) patients treated with intravenous tissue plasminogen activator (IV-tPA). METHODS: We performed an observational study including a retrospective analysis of data from 125 AIS patients with intravenous thrombolysis. General linear models were applied to compare CysC levels between groups with different outcomes; logistic regression analysis and receiver-operating characteristic curves were adopted to identify the association between CysC and the therapeutic effects. RESULTS: Compared with the "good and sustained benefit" (GSB) outcome group (defined as ≥4-point reduction in National Institutes of Health Stroke Scale or a score of 0-1 at 24 h and 7 days) and the "good functional outcome" (GFO) group (modified Rankin Scale score 0-2 at 90 days), serum CysC baseline levels were increased in the non-GSB and non-GFO groups. Logistic regression analysis found that CysC was an independent negative prognostic factor for GSB (odds ratio [OR] 0.010; p = 0.005) and GFO (OR 0.011; p = 0.021) after adjustment for potential influencing factors. Receiver-operating characteristic curves showed the CysC-involved combined models provided credible efficacy for predicting post-90-day favorable clinical outcome (area under the curve 0.86; p < 0.001). CONCLUSIONS: Elevated serum CysC is independently associated with unfavorable clinical outcomes after IV-tPA therapy in AIS. Our findings provide new insights into discovering potential mediators for neuropathological process or treatment in stroke.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Isquemia Encefálica/tratamento farmacológico , Estudos de Casos e Controles , Cistatina C , Fibrinolíticos/uso terapêutico , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento
12.
Ecotoxicol Environ Saf ; 217: 112206, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33866286

RESUMO

1,4-Dioxane (dioxane), an emerging groundwater contaminant, is frequently detected in landfill leachates with its structural analog, tetrahydrofuran (THF). Along with undesirable leakage of landfill leachates, dioxane and THF inevitably percolate into groundwater leading to a broader region of contamination. Cometabolic bioremediation is an effective approach to manage commingled THF and dioxane pollution. In this study, a newly isolated bacterium Arthrobacter sp. WN18 is able to co-oxidize dioxane with THF as the primary substrate. Meanwhile, the THF-induced thmADBC gene cluster was responsible for the dioxane degradation rate indicating THF monooxygenase is the essential enzyme that initializing α-hydroxylation of THF and dioxane. Further, γ-butyrolactone and HEAA were characterized as the key metabolites of THF and dioxane, respectively. In addition, WN18 can tolerate the inhibition of trichloroethylene (5.0 mg/L) as a representative of co-existing leachate constituent, and sustain its activity at various pH (5-11), temperatures (15-42 °C), and salinities (up to 4%, as NaCl wt). Like other Arthrobacter species, WN18 also exhibited the capability of fixing nitrogen. All this evidence indicates the feasibility and advantage of WN18 as a thmADBC-catalyzed inoculator to bioremediate co-contamination of THF and dioxane.


Assuntos
Arthrobacter/metabolismo , Biodegradação Ambiental , Dioxanos/metabolismo , Furanos/metabolismo , Proteínas de Bactérias , Água Subterrânea , Oxigenases de Função Mista , Família Multigênica , Oxirredução , Tricloroetileno , Poluentes Químicos da Água
13.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443603

RESUMO

Abnormal levels of reduced glutathione (GSH) and glutathione reductase (GR) are usually related to a variety of diseases, so it is of great significance to determine the GSH concentration and GR activity. We herein develop a smartphone-assisted colorimetric biosensor for the detection of GSH and GR activity in human serum and mouse liver using hemin/G-quadruplex DNAzyme. Firstly, an obvious color change from colorless to green can be observed, owing to the high peroxidase-like activity of hemin/G-quadruplex DNAzyme toward 2,2'-azino-bis(3-ethylbenzothiozoline-6-sulfonic acid) (ABTS). With the addition of GSH or GR, the H2O2-mediated oxidation of ABTS catalyzed by hemin/G-quadruplex DNAzyme is significantly inhibited, resulting in remarkable color fading. Therefore, the detection of GSH and GR activity can be achieved by observing the color transition or measuring the absorbance at 420 nm. The detection limit was estimated to be as low as 0.1 µM and 10 µU/mL for GSH and GR, respectively. More interestingly, the RGB values of the sensing system can be identified by the smartphone application (APP, color collect), which makes it an ideal format for on-site determination and point-of-care testing (POCT). In addition, the proposed method shows excellent selectivity and acceptable applicability for the determination of GSH concentration and GR activity in human serum samples and mouse liver tissues, which might hold great application potential in clinical diagnosis and drug screening.


Assuntos
Técnicas Biossensoriais/métodos , DNA Catalítico/metabolismo , Glutationa Redutase/sangue , Glutationa/sangue , Hemina/metabolismo , Fígado/metabolismo , Smartphone , Animais , Colorimetria , DNA Catalítico/química , Quadruplex G , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Humanos , Camundongos , Oxirredução
14.
Appl Environ Microbiol ; 86(17)2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32591384

RESUMO

Cometabolic degradation plays a prominent role in bioremediation of commingled groundwater contamination (e.g., chlorinated solvents and the solvent stabilizer 1,4-dioxane [dioxane]). In this study, we untangled the diversity and catalytic functions of multicomponent monooxygenases in Azoarcus sp. strain DD4, a Gram-negative propanotroph that is effective in degrading dioxane and 1,1-dichloroethylene (1,1-DCE). Using a combination of knockout mutagenesis and heterologous expression, a toluene monooxygenase (MO) encoded by the tmoABCDEF gene cluster was unequivocally proved to be the key enzyme responsible for the cometabolism of both dioxane and 1,1-DCE. Interestingly, in addition to utilizing toluene as a primary substrate, this toluene MO can also oxidize propane into 1-propanol. Expression of this toluene MO in DD4 appears inducible by both substrates (toluene and propane) and their primary hydroxylation products (m-cresol, p-cresol, and 1-propanol). These findings coherently explain why DD4 can grow on propane and express toluene MO for active cooxidation of dioxane and 1,1-DCE. Furthermore, upregulation of tmo transcription by 1-propanol underlines the implication potential of using 1-propanol as an alternative auxiliary substrate for DD4 bioaugmentation. The discovery of this toluene MO in DD4 and its degradation and induction versatility can lead to broad applications, spanning from environmental remediation and water treatment to biocatalysis in green chemistry.IMPORTANCE Toluene MOs have been well recognized given their robust abilities to degrade a variety of environmental pollutants. Built upon previous research efforts, this study ascertained the untapped capability of a toluene MO in DD4 for effective cooxidation of dioxane and 1,1-DCE, two of the most prevailing yet challenging groundwater contaminants. This report also aligns the induction of a toluene MO with nontoxic and commercially accessible chemicals (e.g., propane and 1-propanol), extending its implications in the field of environmental microbiology and beyond.


Assuntos
Azoarcus/enzimologia , Proteínas de Bactérias/metabolismo , Dicloroetilenos/metabolismo , Dioxanos/metabolismo , Oxigenases de Função Mista/metabolismo , Oxirredução
15.
Environ Sci Technol ; 54(3): 1898-1908, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31877031

RESUMO

Monitored natural attenuation (MNA) and engineered bioremediation have been recognized as effective and cost-efficient in situ treatments to mitigate 1,4-dioxane (dioxane) contamination. Dioxane metabolism can be initiated by two catabolic enzymes, propane monooxygenase (PRM) and tetrahydrofuran monooxygenase (THM), belonging to the group-6 and 5 of soluble di-iron monooxygenase family, respectively. In this study, we comprehensively compared catalytic behaviors of PRM and THM when individually expressed in the heterologous host, Mycobacterium smegmatis mc2-155. Kinetic results revealed a half-saturation coefficient (Km) of 53.0 ± 13.1 mg/L for PRM, nearly 4 times lower than that of THM (235.8 ± 61.6 mg/L), suggesting that PRM has a higher affinity to dioxane. Exposure with three common co-contaminants (1,1-dichloroethene, trichloroethene, and 1,1,1-trichloroethane) demonstrated that PRM was also more resistant to their inhibition than THM. Thus, dioxane degraders expressing PRM may be more physiologically and ecologically advantageous than those with THM at impacted sites, where dioxane concentration is relatively low (e.g., 250 to 1000 µg/L) with co-occurrence of chlorinated solvents (e.g., 0.5 to 8 mg/L), underscoring the need of surveying both PRM and THM-encoding genes for MNA potential assessment. PRM is also highly versatile, which breaks down cyclic molecules (dioxane, tetrahydrofuran, and cyclohexane), as well as chlorinated and aromatic pollutants, including vinyl chloride, 1,2-dichloroethane, benzene, and toluene. This is the first report regarding the ability of PRM to degrade a variety of short-chain alkanes and ethene in addition to dioxane, unraveling its pivotal role in aerobic biostimulation that utilizes propane, isobutane, or other gaseous alkanes/alkenes (e.g., ethane, butane, and ethene) to select and fuel indigenous microorganisms to tackle the commingled contamination of dioxane and chlorinated compounds.


Assuntos
Dioxanos , Poluentes Químicos da Água , Biodegradação Ambiental , Cinética , Oxigenases de Função Mista
16.
Neural Plast ; 2020: 8874119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33354205

RESUMO

Background: Freezing of gait (FoG) is a disabling gait disorder that commonly occurs in advanced stages of Parkinson's disease (PD). The neuroanatomical mechanisms underlying FoG in PD are still unclear. The present study aims to explore alterations of structural gray matter (GM) in PD patients with FoG. Method: Twenty-four PD patients with FoG (FoG+), 37 PD patients without FoG (FoG-) and 24 healthy controls (HC) were included. All subjects underwent a standardized MRI protocol. The cortical thickness (CTh), segmentation volume without ventricles (BrainSegVolNotVent) and estimated total intracranial volume (eTIV) were analysed using the FreeSurfer pipeline. Results: CTh differences were found in the right middle temporal gyrus (rMTG) generally. Compared to that in HCs, the CTh of the rMTG in both the FoG+ and FoG- groups was smaller, while no significant difference between the FoG+ and FoG- groups. Correlation analyses demonstrated a negative correlation between the CTh of the rMTG and the UPDRS part II score in PD subjects, and a borderline significant correlation between the score of Freezing of Gait Questionnaire (FoGQ) and rMTG CTh. Additionally, receiver operating characteristic curve (ROC) analysis revealed a cut-off point of CTh =3.08 mm in the rMTG that could be used to differentiate PD patients and HCs (AUC =0.79, P <0.01). There were no differences in the BrainSegVolNotVent or eTIV among the 3 groups. Conclusions: Our findings currently suggest no significant difference between FoG+ and FoG- patients in terms of structural gray matter changes. However, decreased CTh in the rMTG related to semantic control may be used as a biomarker to differentiate PD patients and HCs.


Assuntos
Espessura Cortical do Cérebro , Transtornos Neurológicos da Marcha/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Idoso , Feminino , Marcha/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
17.
Neural Plast ; 2020: 8891458, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33101404

RESUMO

Background: Freezing of gait (FOG) is a disabling gait disorder influencing patients with Parkinson's disease (PD). Accumulating evidence suggests that FOG is related to the functional alterations within brain networks. We investigated the changes in brain resting-state functional connectivity (FC) in patients with PD with FOG (FOG+) and without FOG (FOG-). Methods: Resting-state functional magnetic resonance imaging (RS-fMRI) data were collected from 55 PD patients (25 FOG+ and 30 FOG-) and 26 matched healthy controls (HC). Differences in intranetwork connectivity between FOG+, FOG-, and HC individuals were explored using independent component analysis (ICA). Results: Seven resting-state networks (RSNs) with abnormalities, including motor, executive, and cognitive-related networks, were found in PD patients compared to HC. Compared to FOG- patients, FOG+ patients had increased FC in advanced cognitive and attention-related networks. In addition, the FC values of the auditory network and default mode network were positively correlated with the Gait and Falls Questionnaire (GFQ) and Freezing of Gait Questionnaire (FOGQ) scores in FOG+ patients. Conclusions: Our findings suggest that the neural basis of PD is associated with impairments of multiple functional networks. Notably, alterations of advanced cognitive and attention-related networks rather than motor networks may be related to the mechanism of FOG.


Assuntos
Atenção/fisiologia , Encéfalo/fisiopatologia , Cognição/fisiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Doença de Parkinson/fisiopatologia , Idoso , Mapeamento Encefálico , Feminino , Transtornos Neurológicos da Marcha/complicações , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/fisiopatologia , Doença de Parkinson/complicações
18.
Zhongguo Zhong Yao Za Zhi ; 44(5): 870-874, 2019 Mar.
Artigo em Zh | MEDLINE | ID: mdl-30989842

RESUMO

Homology of medicine and food is an important content in Chinese medicine and also works as the basis for guiding the development of compound health food containing Chinese materia medica. The top products,supplements,health care prescriptions,and medicinal meals in traditional herbal texts are the theoretical treasures of Chinese medicine compound health foods. With the implementation of the National Healthy China 2030,China's major health industry faces with tremendous opportunities. It is necessary to develop a batch of compound health food containing Chinese materia medica with Chinese medicine characteristics,in line with the needs of the country and society. Domestic research on compound health food containing Chinese materia medica mainly focuses on the extraction of functional components,preparation molding processes,quality standards,and efficacy evaluation. However,there are still some deficiencies in the related characteristics of traditional Chinese medicine(TCM) theory and function,evaluation criteria of efficacy and safety,new product R&D evaluation system and R&D platform. Based on a large number of previous studies by this laboratory,the views in nature,flavor and efficacy relationship were put forward in this paper. Based on the establishment of the Chinese medicine function-pharmacology-clinical application database system,the Chinese medicine compatibility database system,the Chinese medicine nature and flavor modern research database system,and the evaluation platform for animal models of Chinese medicine; the efficacy study,safety evaluation system,new product research and development evaluation system as well as research and development platform were established,providing a basis for the development and evaluation of compound health food containing Chinese materia medica. The modern scientific connotation of the core efficacy of compound health food containing Chinese materia medica was explained as well,helpful to promote the research and development of compound health food containing Chinese materia medica and play an important role in general health.


Assuntos
Alimentos , Materia Medica , Medicina Tradicional Chinesa , China , Mineração de Dados
19.
Physiol Genomics ; 50(3): 197-207, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29341868

RESUMO

studies have demonstrated that jasmonic acid (JA) reduces root-knot nematode (RKN) infections in tomato plants. RKN invasion is sensed by roots, and root-derived JA signaling activates systemic defense responses, though this is poorly understood. Here, we investigate variations in the RKN-induced transcriptome in scion phloem between two tomato plant grafts: CM/CM ( Lycopersicum esculentum Mill. cv. Castlemart) and CM/ spr2 (a JA-deficient mutant). A total of 8,716 genes were differentially expressed in the scion phloem of the plants with JA-deficient rootstock via RNA sequencing. Among these genes, 535 upregulated and 153 downregulated genes with high copy numbers were identified as significantly differentially expressed. Among them, 34 predicted transcription factor genes were identified. Additionally, we used real-time quantitative PCR to analyze the expression patterns of 42 genes involved in the JA, ethylene, or salicylic acid pathway in phloem under RKN infection. The results suggested that in the absence of JA signaling, the ET signaling pathway is enhanced after RKN infection; however, alterations in the SA signaling pathway were not observed.


Assuntos
Ciclopentanos/metabolismo , Etilenos/metabolismo , Nematoides/fisiologia , Oxilipinas/metabolismo , Doenças das Plantas/genética , Ácido Salicílico/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/parasitologia , Transcrição Gênica , Animais , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Estudos de Associação Genética , Floema/genética , Doenças das Plantas/parasitologia , Transdução de Sinais/genética
20.
Appl Microbiol Biotechnol ; 102(7): 3375-3386, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29464325

RESUMO

Pseudonocardia spp. are receiving increasing attention due to their ability to biodegrade recalcitrant cyclic ether pollutants (e.g., 1,4-dioxane and tetrahydrofuran), as well as for their distinctive ecological niches (e.g., symbiosis with ants/plants and production of antibiotics). Isolating and characterizing Pseudonocardia spp. is thus important to discern their metabolic and physiological idiosyncrasies and advance their potential applications. However, slow growth, low cell yield, and dissimilar colony morphology hinder efficient isolation of Pseudonocardia using conventional plating methods. Here, we develop the first fluorescent probe (Pse631) targeting the 16S rRNA of Pseudonocardia members. In combination with flow cytometry and cell sorting, in situ hybridization with this probe enables sensitive and specific detection of Pseudonocardia cells in mixed cultures and enriched environmental samples without significant false positives, using Escherichia coli, Bacillus subtilis, and Mycobacterium spp. as negative controls. Pseudonocardia dioxanivorans CB1190 cells labeled with Pse631 as a positive control were detected when their relative abundance in the total bacterial community was as low as 0.1%. Effective separation of Pseudonocardia cells from the mixed consortium was confirmed by quantitative PCR analysis of sorted cells. This study provides a culture-independent high-throughput molecular approach enabling effective separation of Pseudonocardia populations from complex microbial communities. This approach will not only facilitate subsequent molecular analyses including species identification and quantification, but also advance understanding of their catabolic capacities and functional molecular diversity.


Assuntos
Actinomycetales/genética , Actinomycetales/isolamento & purificação , Citometria de Fluxo , Hibridização in Situ Fluorescente , Técnicas Microbiológicas/métodos , RNA Ribossômico 16S/genética , Sondas de Oligonucleotídeos/genética , Sondas de Oligonucleotídeos/metabolismo
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