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1.
DNA Cell Biol ; 39(1): 25-36, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31692368

RESUMO

Coronary artery disease (CAD), a common cardiovascular disease, has become a vital cause of mortality worldwide. Genetic microRNA (miR) polymorphisms might contribute to CAD susceptibility. In this study, we selected miR-146a, miR-196a2, and miR-499 single nucleotide polymorphisms and conducted a case-control study. In total, 505 CAD cases and 1109 controls were recruited. We used SNPscan™ genotyping assay to obtain genotyping of miR rs2910164, rs11614913, and rs3746444 variants. We found that miR-196a2 rs11614913 T > C decreased the susceptibility of myocardial infarction (MI) (TC vs. TT: adjusted p = 0.007 and CC/TC vs. TT: adjusted p = 0.012). In female subgroup, our results indicated that miR-196a2 rs11614913 T > C variants might also decrease the susceptibility of CAD (TC vs. TT: adjusted p = 0.017 and TC/CC vs. TT: adjusted p = 0.015). In summary, these results suggest that miR-196a2 rs11614913 T > C locus decreases the susceptibility of CAD in female and MI subgroups. However, further studies are needed to validate the potential associations of miR-196a2 rs11614913 locus with CAD.

2.
J Hazard Mater ; 381: 120961, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31412305

RESUMO

We design a novel cationic metal-organic framework hybrid ultrafiltration polyvinylidene fluoride membrane (PVA/Cu-iMOFs/PVDF-0.05) and report its unique capture of aqueous perchlorate (ClO4-) at ppm-level. This membrane outperformed traditional adsorption materials and exhibited a specific affinity toward ClO4- in the presence of various competing anions at greater levels (up to a concentration ratio of 20). In the batch experiment, the ClO4- removal ratio reached 99.6% over a wide pH range (3˜10). Membrane filtration by using a 12.56 cm2 PVA/Cu-iMOFs/PVDF-0.05 membrane could effectively treat 4.71 L of ClO4--contaminated water before breakthrough occurred, while maintaining a satisfactory permeability (˜627.32 L/(m2 h bar)) and antifouling property. The exhausted membrane could easily be regenerated in aminoethanesulfonic acid solution for repeated use with a negligible decrease in capacity. Moreover, the membrane showed excellent long-term stability in a cross-flow filtration process due to the amido bond between the Cu-iMOFs and membrane surface as well as the "protection" of polyvinyl alcohol. Selective and reversible ion-exchange between the sulfonic acid (R-SO3) ligands of Cu-iMOFs and tetrahedral oxo-anionic species was verified to be the pathway for ClO4- trapping. Thus, other problematic elements that also occur in tetrahedral form in water can be removed by this method.

3.
Oxid Med Cell Longev ; 2019: 4935237, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31814879

RESUMO

Background: Given that the dysregulation of iron homeostasis leads to genomic instability, iron has been linked to cellular aging. However, epidemiological research on dietary iron intake and cellular aging markers is scarce. The aim of this study was to explore the relationship between dietary iron intake and cellular aging markers and to investigate whether tumor necrosis factor-α (TNFα) mediated this relationship. Methods: We conducted a cross-sectional analysis with a total of 467 subjects. Detailed dietary data were obtained using 24 h food recalls. Peripheral blood leukocyte telomere length (LTL) and mitochondrial DNA copy number (mtDNAcn) were assessed using real-time PCR assay. The association between dietary iron intake and cellular aging markers and TNFα and superoxide dismutase (SOD) was analyzed by Pearson correlation analysis and regression models adjusted by covariates. Simple mediation models were generated to examine whether TNFα mediated the association between iron intake and cellular aging markers using PROCESS macro Version 3.3. Results: The study population contained more women than men, but their basic demographic and metabolic characteristics did not differ. After adjusting for age, LTL was the same for men and women, while mtDNAcn was lower in men. Multiple linear regression adjusted for confounding factors found that iron intake was negatively associated with LTL only in women and negatively associated with mtDNAcn only in men. Moreover, iron intake was positively associated with TNFα in both women and men but positively associated with SOD only in men. Path modeling showed that TNFα significantly mediated the indirect detrimental effect of iron intake on LTL only in women; in men, mediation of the indirect effect of iron intake on mtDNAcn by TNFα did not reach significance. Conclusions: The study found sex-specific negative associations between dietary iron intake and cellular aging markers in that iron intake had deleterious effects on LTL attrition in women and mtDNAcn in men; only the former was partly mediated by TNFα. Consequently, when dietary iron intake and iron supplementation is recommended, the effects of iron imbalance on genomic stability and cellular aging markers must be considered.

4.
BMC Vet Res ; 15(1): 288, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409367

RESUMO

BACKGROUND: In China, although the ALV eradication program and the MD vaccination strategy greatly reduce the disease burdens caused by the infection of ALV and MDV, the frequent emergence of novel ALV-K or vvMDV in the vaccinated chicken flock challenges the current control strategies for both diseases. RESULTS: In Guangdong Province, an indigenous chicken flock was infected with neoplastic disease. Hematoxylin-eosin staining of the tissues showed the typical characteristics of MDV and classical ALV infection. The PCR and sequencing data demonstrated that the identified MDV was clustered into a very virulent MDV strain endemic in domestic chickens in China. Moreover, subgroups ALV-A and ALV-K were efficiently recovered from two samples. The full genome sequence revealed that the ALV-K isolate was phylogenetically close to the ALV TW3593 isolate from Taiwan Province. CONCLUSIONS: A co-infection of vvMDV with multiple ALV subgroups emerged in a chicken flock with neoplastic disease in Guangdong Province. The co-infection with different subgroups of ALV with vvMDV in one chicken flock poses the risk for the emergence of novel ALVs and heavily burdens the control strategy for MDV.


Assuntos
Vírus da Leucose Aviária/classificação , Leucose Aviária/virologia , Galinhas , Coinfecção , Doença de Marek/virologia , Animais , Leucose Aviária/epidemiologia , Vírus da Leucose Aviária/genética , China/epidemiologia , Doença de Marek/epidemiologia , Filogenia , Virulência
5.
Environ Pollut ; 253: 722-730, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31344535

RESUMO

Though the toxicity of strobilurins on non-target aquatic organisms has been characterized, the associated toxic mechanisms have not been fully explored. The present study showed that the larval stage was the most sensitive developmental stage in zebrafish, and pyraclostrobin (PY) had the highest acute toxicity to embryos, larvae, juvenile and adult with 96 h-LC50 at 0.048 mg/L, 0.029 mg/L, 0.039 mg/L, 0.031 mg/L respectively, when compared with the toxicity of trifloxystrobin (TR), kresoxim-methyl (KM) and azoxystrobin (AZ) at corresponding developmental stage. Then we investigated the transcriptomics and developmental toxicity of TR, KM, AZ and PY on zebrafish embryos after 72 h exposure. RNA-seq revealed that the pathways related to cell apoptosis and cancer, and cellular components organelle membrane and mitochondrion, were markedly affected after TR, KM, AZ and PY exposure during zebrafish early life stages. The results were further confirmed by the induction of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD) activities, the elevation of H2O2, malondialdehyde (MDA) and reactive oxygen species (ROS) level, as well as the reduction of intracellular calcium ions (Ca2+) and mitochondrial membrane potential (MMP), which indicated that strobilurins could cause mitochondrial dysfunction and cell apoptosis. The present study was performed a systematic analysis of strobilurins to zebrafish at multi-levels, which provided suggestions for further investigation of molecular mechanisms underlying the toxicity induced by strobilurins on aquatic organisms.


Assuntos
Fungicidas Industriais/toxicidade , Estrobilurinas/toxicidade , Acetatos/toxicidade , Animais , Antioxidantes/metabolismo , Apoptose , Catalase/metabolismo , Peróxido de Hidrogênio/metabolismo , Iminas/toxicidade , Larva/metabolismo , Malondialdeído/metabolismo , Mitocôndrias/metabolismo , Estresse Oxidativo , Pirimidinas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Testes de Toxicidade , Transcriptoma , Peixe-Zebra/metabolismo
6.
Vet Microbiol ; 231: 214-217, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30955812

RESUMO

In this study, a recombinant ALV with ALV-K env and ALV-J backbone was generated (designated ALV-K-env-J) and tested in vitro and in vivo. The growth curve in DF1 cells showed that the recombinant virus replicated more efficiently in comparison with the ALV-J and ALV-K. Although all the infected chickens showed growth retardation compared with the non-infected chickens, the viral and serological detection showed that the positive rate and virus load detected in blood and cloaca, and the positive rate and titer of antibody against p27 from the chickens infected with ALV-K-env-J were higher than those from the chickens infected with the ALV-K, but less than those from the chickens infected with the ALV-J. All these data clearly demonstrated that the recombination event in this study increased the pathogenesis of ALV-K, and the potential recombination between different ALV subgroups should be worried when the clinical co-infections occur.


Assuntos
Vírus da Leucose Aviária/genética , Vírus da Leucose Aviária/patogenicidade , Leucose Aviária/virologia , Doenças das Aves Domésticas/virologia , Recombinação Genética , Animais , Anticorpos Antivirais/sangue , Leucose Aviária/imunologia , Galinhas/virologia , Cloaca/virologia , Doenças das Aves Domésticas/imunologia , Testes Sorológicos , Carga Viral
7.
J Hazard Mater ; 368: 698-704, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30739022

RESUMO

To activate zero-valent iron (ZVI) for efficient nitrobenzene (NB) reduction, a hybrid Fe0/Fe3O4/FeCl2 microcomposite (hZVIbm) was synthesized via simple ball-milling of the ternary mixture of ZVI, Fe3O4, and FeCl2·4H2O (hZVI). SEM-EDX and time-of-flight secondary ion mass spectroscopy (ToF-SIMS) indicated the hZVIbm microcomposite (10-20 µm) consisted of Fe0 core covered by ∼3.3 µm-thick shell decorated with Fe3O4/FeCl2 fine particles (0.1-2 µm). Efficient removal (>95%) of NB (200 mg/L) was achieved by hZVIbm (2.0 g Fe/L) in 30 min over a wide pH range from 3 to 9. Notably, the NB removal efficiency of hZVIbm was over 30 times higher than the virgin ZVI or over three times higher than hZVI. The enhanced reactivity synergistically resulted from both chemical and physical aspects. Chemically, the Fe3O4/FeCl2-inlaid shell and the Fe(II) components played significant activation roles, as observed from the comparative experiments in their absence via pretreatments of hZVIbm by sonication and rinsing, respectively, with direct evidence of depassivation effect by XRD analysis. Physically, the ball-milling-induced inter-particle compaction effect was considered crucial to facilitate the interfacial mass/electron transfer processes during the reduction. The reduction pathway from NB to aniline via two intermediates was analyzed by liquid chromatography.

8.
Brain Behav ; 9(2): e01201, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30623612

RESUMO

BACKGROUND: Cognitive behavioral therapy (CBT) is an effective treatment for Obsessive-compulsive disorder (OCD). Structural and functional white matter defects may suggest a vital neurobiological basis of OCD. However, the effects of CBT on white matter in OCD remain unknown. OBJECTIVE: The aim was to investigate white matter changes and the effect of CBT on white matter in OCD patients. METHODS: Fractional anisotropy (FA) maps were acquired using DTI. Participants included 85 patients with OCD and 90 healthy controls. VBM was then performed to detect regions with significant group differences. RESULTS: Obsessive-compulsive disorder patients exhibited significantly reduced FA values in bilateral OFC, right cerebellum, and left SPG, while higher FA values were observed in right PUT compared with healthy controls. Following CBT, OCD patients showed higher FA values in right MFG, left OFC, right cerebellum, and left MTG, and decreased FA values in right PUT in comparison with pretreatment. Furthermore, FA values in the left OFC of patients were significantly positively correlated with the Y-BOCS and its associated Compulsions subscale, and FA values in the right PUT were positively correlated with Compulsions subscale. In addition, the percentage change in FA values in left MTG was positively correlated with the percentage reduction in Compulsions subscale, while the percentage change in FA values in left OFC and right PUT was negatively correlated with the percentage reductions in Obsessive and Compulsions subscale, respectively. CONCLUSIONS: Our findings demonstrate the abnormalities of white matter microstructure in unmedicated patients with OCD. These abnormalities may be partly reversed by CBT.


Assuntos
Terapia Cognitivo-Comportamental/métodos , Transtorno Obsessivo-Compulsivo , Substância Branca , Adulto , Anisotropia , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtorno Obsessivo-Compulsivo/patologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Transtorno Obsessivo-Compulsivo/terapia , Resultado do Tratamento , Substância Branca/patologia , Substância Branca/fisiopatologia
9.
Am J Physiol Lung Cell Mol Physiol ; 316(1): L35-L44, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30234377

RESUMO

Increased pulmonary vascular permeability is a hallmark of acute lung injury (ALI). Connexin 40 (Cx40) is a gap junctional protein abundantly present in the lung microvascular endothelium. Yet, the role of Cx40 in the regulation of lung vascular permeability and its underlying mechanisms are unclear. Here, we tested the hypothesis that Cx40 participates in regulation of lung endothelial permeability via a mechanism involving a Rho-associated protein kinase (ROCK) dependent regulation of myosin light chain (MLC). In murine models of intratracheal acid- or LPS-induced lung injury, genetic deficiency of Cx40 attenuated key features of ALI including vascular barrier failure. In human pulmonary microvascular endothelial cells (PMVECs), thrombin-induced loss of transendothelial electrical resistance was attenuated by a Cx40-inhibiting mimetic peptide (40GAP27), Cx40-specific shRNA, or ROCK inhibitor Y27632. In isolated perfused mouse lungs, platelet-activating factor-induced lung weight gain was abrogated by gap junction blocker carbenoxolone, 40GAP27, Y27632, or genetic deficiency of Cx40. Phosphorylation of MLC20 increased drastically in both LPS-treated PMVECs and HCl-treated mouse lungs. Expression of ROCK1 was increased in both LPS-treated PMVECs and HCl-treated mouse lungs, and paralleled by phosphorylation of MLC20. Coimmunoprecipitation experiments revealed protein-protein interaction between ROCK1 and Cx40. LPS-induced upregulation of ROCK1 and phosphorylation of MLC20 were blocked by knockdown of Cx40. LPS caused phosphorylation of myosin phosphatase targeting subunit 1, which could be abrogated by Y27632 or Cx40-shRNA. Our findings reveal a role of Cx40 in regulation of ROCK1 and MLC20 that contributes critically to lung vascular barrier failure in ALI.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Permeabilidade Capilar , Conexinas/metabolismo , Endotélio Vascular/metabolismo , Pulmão/metabolismo , Cadeias Leves de Miosina/metabolismo , Transdução de Sinais , Quinases Associadas a rho/metabolismo , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Animais , Conexinas/genética , Endotélio Vascular/patologia , Lipopolissacarídeos/toxicidade , Pulmão/patologia , Masculino , Camundongos , Camundongos Knockout , Cadeias Leves de Miosina/genética , Fosfatase de Miosina-de-Cadeia-Leve/genética , Quinases Associadas a rho/genética
10.
J Hazard Mater ; 365: 312-321, 2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30447639

RESUMO

Multifunctional ultrafiltration membranes need to be further developed with ultrafiltration performance and high multifunctional decontamination efficiency. Here, the MIL-PVDF multifunctional ultrafiltration membrane with ultrahigh MIL loading was demonstrated by a new blending method of predispersion in acetone and thermally induced phase separation. Due to the improved dispersity and restriction of pore size, the MIL-53(Fe) mass loading was as high as approximately 61%. The new membrane showed high performance for methylene blue (MB) removal and maintained high permeability and ultrafiltration efficiency. The characteristics of the membranes were analyzed to explain the above advantages. Meanwhile, compared to the traditional blend ultrafiltration membrane, the 67-MIL-PVDF membrane showed an 9-fold increase in effective treatment volume for more than 75% MB removal. The contribution and efficiency of adsorption and catalytic oxidation were analyzed and explained. The relationship between them was confirmed as being independent, and the reasons for this independence were proposed. Additionally, the mechanism of multifunctional decontamination and permeability by MIL-PVDF membranes was proposed. Moreover, the 67-MIL-PVDF membrane was also suitable for long-term run and real wastewaters treatment. In conclusion, this study sheds new light on the preparation strategy for multifunctional blend ultrafiltration membranes with ultrahigh particles loading displaying high decontamination and permeability performance.

11.
J Cell Biol ; 218(1): 267-284, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30538141

RESUMO

Mutations in ATP13A2 cause Kufor-Rakeb syndrome, an autosomal recessive form of juvenile-onset atypical Parkinson's disease (PD). Recent work tied ATP13A2 to autophagy and other cellular features of neurodegeneration, but how ATP13A2 governs numerous cellular functions in PD pathogenesis is not understood. In this study, the ATP13A2-deficient mouse developed into aging-dependent phenotypes resembling those of autophagy impairment. ATP13A2 deficiency impaired autophagosome-lysosome fusion in cultured cells and in in vitro reconstitution assays. In ATP13A2-deficient cells or Drosophila melanogaster or mouse tissues, lysosomal localization and activity of HDAC6 were reduced, with increased acetylation of tubulin and cortactin. Wild-type HDAC6, but not a deacetylase-inactive mutant, restored autophagosome-lysosome fusion, antagonized cortactin hyperacetylation, and promoted lysosomal localization of cortactin in ATP13A2-deficient cells. Mechanistically, ATP13A2 facilitated recruitment of HDAC6 and cortactin to lysosomes. Cortactin overexpression in cultured cells reversed ATP13A2 deficiency-associated impairment of autophagosome-lysosome fusion. PD-causing ATP13A2 mutants failed to rescue autophagosome-lysosome fusion or to promote degradation of protein aggregates and damaged mitochondria. These results suggest that ATP13A2 recruits HDAC6 to lysosomes to deacetylate cortactin and promotes autophagosome-lysosome fusion and autophagy. This study identifies ATP13A2 as an essential molecular component for normal autophagy flux in vivo and implies potential treatments targeting HDAC6-mediated autophagy for PD.


Assuntos
Autofagossomos/metabolismo , Cortactina/genética , Desacetilase 6 de Histona/genética , Lisossomos/metabolismo , Doença de Parkinson Secundária/genética , ATPases Translocadoras de Prótons/genética , Sequência de Aminoácidos , Anilidas/farmacologia , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/ultraestrutura , Autofagia/efeitos dos fármacos , Autofagia/genética , Cortactina/metabolismo , Modelos Animais de Doenças , Drosophila melanogaster , Regulação da Expressão Gênica , Desacetilase 6 de Histona/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Humanos , Ácidos Hidroxâmicos/farmacologia , Leupeptinas/farmacologia , Glicoproteínas de Membrana Associadas ao Lisossomo/genética , Glicoproteínas de Membrana Associadas ao Lisossomo/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/ultraestrutura , Masculino , Fusão de Membrana/efeitos dos fármacos , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Mitocôndrias/ultraestrutura , Doença de Parkinson Secundária/metabolismo , Doença de Parkinson Secundária/patologia , ATPases Translocadoras de Prótons/deficiência , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
12.
Chemosphere ; 219: 517-525, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30553212

RESUMO

Kresoxim-methyl (KM) is a broad spectrum strobilurin fungicide that has been used widely on crops around the world. In the present study, we aimed to investigate the toxic effects of KM using various sublethal endpoints during zebrafish (Danio rerio) larval development. Results showed that the LC50 values of KM to zebrafish at multiple life stages (embryo, larvae, juvenile and adult) were 0.340, 0.224, 0.328 and 0.436 mg/L, respectively. The transcription patterns of 45 genes involved in hypothalamic-pituitary-thyroid/gonadal (HPT/HPG) axis, oxidative stress and apoptosis revealed KM could affect zebrafish larval development at multiple pathways. The activities of aromatase, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), caspase 3 (Cas3) and caspase 9 (Cas9), and the levels of estradiol (E2), vitellogenin (VTG), thyroid hormones (T3 and T4), reactive oxygen species (ROS) and ATP after embryos exposed to KM for 3 d, 6 d and 10 d were correlated well with the transcription of the corresponding molecules involved in these pathways. In addition to providing the first description of the toxic effects induced by KM during larval development, the results of present study also provided the potential mechanisms of KM on multi-level biomarker responses in larval zebrafish.


Assuntos
Larva/efeitos dos fármacos , Estágios do Ciclo de Vida/efeitos dos fármacos , Estrobilurinas/toxicidade , Peixe-Zebra/crescimento & desenvolvimento , Animais , Apoptose/efeitos dos fármacos , Fungicidas Industriais/metabolismo , Fungicidas Industriais/toxicidade , Larva/enzimologia , Larva/crescimento & desenvolvimento , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Peixe-Zebra/metabolismo
13.
Front Microbiol ; 9: 2989, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30564223

RESUMO

The purpose of this study was to investigate the occurrence of plasmid-mediated colistin resistance gene mcr-1 in Enterobacteriaceae isolates from companion animals in Guangzhou, China. Enterobacteriaceae isolated from 180 samples collected from cats and dogs were screened for mcr-1 by PCR and sequencing. MCR-1-producing isolates were further characterized by multilocus sequence typing and pulsed-field gel electrophoresis (PFGE). Plasmid characterization was performed by conjugation, replicon typing, S1-PFGE, and Southern blot hybridization. Plasmid pHN6DS2 as a representative IncN1-IncHI2/ST3 plasmid from ST93 E. coli was fully sequenced. pHN6DS2-like plasmids were screened by PCR-mapping and sequencing. The mcr-1 gene was detected in 6.25% (8/128) Escherichia coli isolates, of which, five belonged to E. coli ST93 and had identical PFGE patterns, resistance profiles and resistance genes. mcr-1 genes were located on ∼244.4 kb plasmids (n = 6), ∼70 kb plasmids, and ∼60 kb plasmids, respectively. Among them, five mcr-1-carrying plasmids were successfully transferred to recipient by conjugation experiments, and were classified as IncN1-IncHI2/ST3 (∼244.4 kb, n = 4, all obtained from E. coli ST93), and IncI2 (∼70 kb, n = 1), respectively. Plasmid pHN6DS2 contained a typical IncHI2-type backbone, with IncN1 segment (ΔrepA-Iterons I-gshB-ΔIS1294) inserted into the multiresistance region, and was similar to other mcr-1-carrying IncHI2/ST3 plasmids from Enterobacteriaceae isolates of various origins in China. The remaining five mcr-1-bearing plasmids with sizes of ∼244.4 kb were identified to be pHN6DS2-like plasmids. In conclusion, clonal spread of ST93 E. coli isolates was occurred in companion animals in Guangzhou, China.

14.
Int J Nanomedicine ; 13: 8325-8338, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30584303

RESUMO

The hemostatic and anti-infection treatments in the field of orthopedics are always the pivotal yet challenging topics. In the first part of this review, synthesized or naturally derived nanoscale agents and materials for hemostatic treatment in orthopedic surgery are introduced. The hemostatic mechanisms and the safety concerns of these nanotechnology-enabled materials are discussed. Beside the materials to meet hemostatic needs in orthopedic surgery, the need for antimicrobial or anti-infection strategy in orthopedic surgery also becomes urgent. Nanosilver and its derivatives have the most consistent anti-infective effect and thus high translational potential for clinical applications. In the second part, the factors affecting the antimicrobial effect of nanosilver and its application status are summarized. Finally, the status and translational potential of various nanotechnology-enabled materials and agents for hemostatic and anti-infective treatments in orthopedic surgery are discussed.


Assuntos
Anti-Infecciosos/farmacologia , Materiais Biocompatíveis/química , Hemostáticos/farmacologia , Nanotecnologia/métodos , Procedimentos Ortopédicos , Animais , Humanos , Pesquisa Médica Translacional
15.
Chemosphere ; 211: 139-148, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30071425

RESUMO

Chemical cleaning is an important approach for alleviating severe fouling in membrane separation processes. In this study, lysozyme (LYS) was exposed to sodium hypochlorite (NaClO) with varied concentrations (0-2000 ppm) to understand the changes in the physicochemical properties and functional groups as well as the variations in membrane permeabilities. The results showed that membrane filterability exhibited an obvious 'U-shaped' trend, and the valley existed when the ratio of Cl/C (the ratio of NaClO and TOC concentrations in feed water) is among 1.35-3.09. Upon exposure to low dose NaClO, three-dimensional fluorescence excitation-emission matrix (3D-EEM) spectra showed that tryptophan protein substances were transformed to more hydrophobic humic-like substances. Fourier transform infrared (FTIR) analysis further confirmed that exposure to low dose NaClO promoted the breakage of aromatic substituents, leading to the formation of hydrophobic condensed aromatic substances. On the contrary, at high NaClO loads, protein structures were destroyed completely and almost no obvious fluorescent intensities could be detected, which promoted the recovery of membrane filterabilities. Notably, the chemical cleaning mechanisms of fouled membranes with NaClO were understood in depth in this study. These results provide new information about the oxidation products of LYS and the cleaning efficiency upon exposure to NaClO.


Assuntos
Permeabilidade , Hipoclorito de Sódio/química , Purificação da Água/métodos , Interações Hidrofóbicas e Hidrofílicas
16.
Environ Int ; 120: 63-71, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30064056

RESUMO

The prevalence of antibiotic resistance in drinking water system is pressing public health risk. Antibiotic resistance conferred by chromosomal mutations often produces fitness cost, which may affect its spread and persistence. In this study, the rifampin-resistant strains were competed with their wild-type counterparts at different nutrient levels. It was observed that the ratio of the absolute number between resistant and wild-type cells quickly decreased under rich nutrient conditions, but it slowly reduced or remained stable in the poor nutrient medium. This finding suggested that poor nutrient conditions resulted in the reduction of fitness cost of antibiotic resistance, i.e. the resistant bacteria became more competitive. Implying mechanisms analysis found that the differences of metabolic activity between wild-type and rifampin-resistant strains was significant smaller (P < 0.05) at low nutrient levels. Additionally, distinguishable large colony size rifampin-resistant strains were observed during competition assay. DNA sequencing of RNA polymerase subunit genes further revealed that these colonies could be adaptive mutants from wild-type strain in rpoB gene. To our knowledge, this is the first study to reveal that the oligotrophic conditions facilitate the persistence of antibiotic resistance in drinking water by reducing the fitness cost of the resistant strains.


Assuntos
Bactérias , Meios de Cultura , Farmacorresistência Bacteriana/genética , Aptidão Genética/genética , Mutação/genética , Bactérias/efeitos dos fármacos , Bactérias/genética , Cromossomos Bacterianos/genética , Meios de Cultura/química , Meios de Cultura/farmacologia , Aptidão Genética/efeitos dos fármacos
17.
Environ Sci Technol ; 52(18): 10657-10664, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30130960

RESUMO

Fenton reaction is a widely used pretreatment technology to degrade toxic metal-organic complexes. However, its efficiency is greatly compromised for Cr(III)-organic complexes due to accumulation of more toxic Cr(VI) and pH dependence. Herein, we proposed a combined pyrite/H2O2-precipitation process to efficiently remove Cr(III) (initially at 10.4 mg Cr/L) complexed by various ligands (citrate, EDTA, oxalate, and tartrate). Negligible Cr(VI) and <0.3 mg/L Cr were detected in the effluent treated by pyrite/H2O2-precipitation over a wide pH range of 3-9. In contrast, > 0.5 mg/L Cr(VI) and >5 mg/L Cr remained after treatment by the ZVI/H2O2-precipitaion process at pH0 > 5. As for the mechanisms, pyrite/H2O2 produced a considerable amount of aqueous Fe(II) to initiate Fenton reaction, concurrently releasing massive H+ to keep the reaction pH at ∼3.0 irrespective of the initial pHs. The generated •OH radicals oxidized Cr(III) into Cr(VI) and thereby releasing the organic ligands for further mineralization. The generated Cr(VI) was in situ reduced back to Cr(III) by aqueous Fe(II) and FeS2. Subsequently, all the free metal ions including Cr(III), Fe(III), and Fe(II) were removed via precipitation. Kinetic modeling of the pyrite/H2O2 process involving 17 reactions was performed to verify the proposed mechanism. Additionally, the effectiveness of the combined process was further validated by its satisfactory performance in treating authentic tannery wastewater.


Assuntos
Peróxido de Hidrogênio , Água , Cromo , Descontaminação , Compostos Férricos , Ferro , Oxirredução , Sulfetos
18.
mSphere ; 3(4)2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-30021873

RESUMO

To understand the underlying evolution process of F33:A-:B- plasmids among Enterobacteriaceae isolates of various origins in China, the complete sequences of 17 blaCTX-M-harboring F33:A-:B- plasmids obtained from Escherichia coli and Klebsiella pneumoniae isolates from different sources (animals, animal-derived food, and human clinics) in China were determined. F33:A-:B- plasmids shared similar plasmid backbones comprising replication, leading, and conjugative transfer regions and differed by the numbers of repeats in yddA and traD and by the presence of group II intron, except that pHNAH9 lacked a large segment of the leading and transfer regions. The variable regions of F33:A-B- plasmids were distinct and were inserted downstream of the addiction system pemI/pemK, identified as the integration hot spot among F33:A-B- plasmids. The variable region contained resistance genes and mobile elements or contained segments from other types of plasmids, such as IncI1, IncN1, and IncX1. Three plasmids encoding CTX-M-65 were very similar to our previously described pHN7A8 plasmid. Four CTX-M-55-producing plasmids contained multidrug resistance regions related to that of F2:A-B- plasmid pHK23a from Hong Kong. Five plasmids with IncN and/or IncX replication regions and IncI1-backbone fragments had variable regions related to those of pE80 and p42-2. The remaining five plasmids with IncN replicons and an IncI1 segment also possessed closely related variable regions. The diversity in variable regions was presumably associated with rearrangements, insertions, and/or deletions mediated by mobile elements, such as IS26 and IS1294IMPORTANCE Worldwide spread of antibiotic resistance genes among Enterobacteriaceae isolates is of great concern. F33:A-:B- plasmids are important vectors of resistance genes, such as blaCTX-M-55/-65, blaNDM-1, fosA3, and rmtB, among E. coli isolates from various sources in China. We determined and compared the complete sequences of 17 F33:A-:B- plasmids from various sources. These plasmids appear to have evolved from the same ancestor by mobile element-mediated rearrangement, acquisition, and/or loss of resistance modules and similar IncN1, IncI1, and/or IncX1 plasmid backbone segments. Our findings highlight the evolutionary potential of F33:A-:B- plasmids as efficient vectors to capture and diffuse clinically relevant resistance genes.


Assuntos
Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/veterinária , Escherichia coli/enzimologia , Microbiologia de Alimentos , Klebsiella pneumoniae/enzimologia , Plasmídeos/análise , beta-Lactamases/genética , Animais , Conjugação Genética , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Evolução Molecular , Transferência Genética Horizontal , Variação Genética , Hong Kong , Humanos , Integrons , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Plasmídeos/classificação , Recombinação Genética
19.
Water Res ; 143: 87-98, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-29940365

RESUMO

Enhanced removal of trace toxic metals (ppm level) from high-salinity wastewater is crucial to ensure water safety but still a challenging task. In this study, we fabricated a new hybrid ultrafiltration membrane (PAA/ZIF-8/PVDF) by immobilizing zeolitic imidazolate framework-8 (ZIF-8) particles onto the surface of trimesoyl chloride (TMC)-modified polyvinylidene fluoride (PVDF) membrane under protection of polyacrylic acid (PAA) layer. The resultant PAA/ZIF-8/PVDF membrane exhibited relatively high water flux of 460 L·m-2 h-1 and outstanding nickel ion (Ni(II)) capacity (219.09 mg/g) from a synthetic high-salinity ([Na+] = 15000 mg/L) wastewater. X-ray photoelectron spectroscopic studies revealed that preferable Ni(II) uptake was mainly attributed to the specific interaction between Ni(II) and hydroxyl groups on ZIF-8 frameworks and carboxyl groups in PAA layer as well. Compared to PAA, ZIF-8 could selectively bind Ni(II) with negligible effect exerted by concentrated sodium ion. The filtration study showed that the 12.56-cm2 membrane could effectively treat 5.76 L high-salinity wastewater ([Ni(II)0 = 2 mg/L, [Na+]0 = 15000 mg/L) to conspicuously reduce Ni(II) below the maximum contaminant level of China, 0.1 mg/L. Moreover, the hybrid membrane could be regenerated by HCl-NaCl solution (pH = 5.5) for repeated use under direct current electric field. Generally speaking, the newly developed ZIF-8 hybrid ultrafiltration membrane showed a very promising potential in enhanced removal of toxic metals from high-salinity wastewater treatment.


Assuntos
Membranas Artificiais , Níquel/isolamento & purificação , Ultrafiltração/instrumentação , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Resinas Acrílicas/química , Adsorção , Concentração de Íons de Hidrogênio , Imidazóis/química , Estruturas Metalorgânicas/química , Níquel/química , Espectroscopia Fotoeletrônica , Polivinil/química , Salinidade , Espectroscopia de Infravermelho com Transformada de Fourier , Ultrafiltração/métodos , Poluentes Químicos da Água/química , Difração de Raios X , Zeolitas/química
20.
Vet Res ; 49(1): 41, 2018 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-29720272

RESUMO

In this study, we identified a chicken liver cell line (LMH) which could strongly support the replication of ALV-J (Subgroup J of avian leukosis virus) with high viral titer. Notably, ALV-J was efficiently detected by ELISA in LMH cells 1 day before DF1 cells. In comparison with DF1 cells, LMH cells not only expressed higher levels of ALV-J receptor chNHE-1, but also possessed a more efficient protein expression system for foreign genes. Thus, LMH cells could be a novel tool to shorten the ALV-J eradication approach and accelerate studies on the pathogenesis and oncogenesis of ALV-J.


Assuntos
Vírus da Leucose Aviária/isolamento & purificação , Leucose Aviária/diagnóstico , Galinhas , Carga Viral/veterinária , Replicação Viral , Animais , Leucose Aviária/virologia , Linhagem Celular/virologia , Ensaio de Imunoadsorção Enzimática/veterinária , Fígado , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/virologia , Carga Viral/métodos
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