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1.
Anal Chim Acta ; 1314: 342781, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38876519

RESUMO

BACKGROUND: Okadaic acid (OA), as a diarrhetic shellfish poisoning, can increase the risk of acute carcinogenic or teratogenic effects for the ingestion of OA contaminated shellfish. At present, much effort has been made to graft immunoassay onto a paper substrate to make paper-based sensors for rapid and simple detection of shellfish toxin. However, the complicated washing steps and low protein fixation efficiency on the paper substrate need to be further addressed. RESULTS: A novel paper-tip immunosensor for detecting OA was developed combined with smartphone and naked eye readout. The trapezoid paper tip was consisted of quantitative and qualitative detection zones. To improve the OA antigen immobilization efficiency on the paper substrate, graphene oxide (GO)-assisted protein immobilization method was introduced. Meanwhile, Au nanoparticles composite probe combined with the lateral flow washing was developed to simplify the washing step. The OA antigen-immobilized zone, as the detection zone Ⅰ, was used for quantitative assay by smartphone imaging. The paper-tip front, as the detection zone Ⅱ, which could qualitatively differentiate OA pollution level within 45 min using the naked eye. The competitive immunoassay on the paper tip exhibited a wide linear range for detecting OA (0.02-50 ng∙mL-1) with low detection limit of 0.02 ng∙mL-1. The recovery of OA in spiked shellfish samples was in the range of 90.3 %-113.%. SIGNIFICANCE: These results demonstrated that the proposed paper-tip immunosensor could provide a simple, low-cost and high-sensitivity test for OA detection without the need for additional large-scale equipment or expertise. We anticipate that this paper-tip immunosensor will be a flexible and versatile tool for on-site detecting the pollution of marine products.


Assuntos
Técnicas Biossensoriais , Ouro , Grafite , Ácido Okadáico , Papel , Smartphone , Grafite/química , Ácido Okadáico/análise , Imunoensaio/métodos , Ouro/química , Nanopartículas Metálicas/química , Proteínas Imobilizadas/química , Limite de Detecção , Animais , Anticorpos Imobilizados/imunologia , Anticorpos Imobilizados/química
2.
Environ Res ; 252(Pt 3): 119043, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692422

RESUMO

It is of great significance to establish an effective method for removing Cr(VI) from wastewater. Herein, Fe-doped g-C3N4 (namely Fe-g-C3N4-2) was synthesized and then employed as photocatalyst to conduct the test of Cr(VI) reduction. Notably, the embedding of Fe ion in g-C3N4 can offer the Fe2+/Fe3+ redox couples, so reducing the interfacial resistance of charge transfer and suppressing the recombination of photogenerated electrons and holes. The impurity energy levels will form in g-C3N4 after the introduction of Fe ion, thereby boosting the light absorption capacity of catalyst. Thus, Fe-g-C3N4-2 showed good performance in photocatalytic Cr(VI) reduction, and the reduction efficiency of Cr(VI) can reach 39.9% within 40 min. Different with many previous studies, current work unexpectedly found that the addition of p-benzoquinone (BQ) can promote the Cr(VI) reduction, and the reduction efficiency of Cr(VI) over Fe-g-C3N4-2 was as high as 93.2% in the presence of BQ (1.5 mM). Further analyses showed that BQ can be reduced to hydroquinone (HQ) by photogenerated electrons, and UV light can also directly induce BQ to generate HQ by using H2O as the hydrogen donor. The HQ with reducing ability can accelerate the Cr(VI) reduction. In short, current work shared some novel insights into photocatalytic Cr(VI) reduction in the presence of BQ. Future research should consider possible reactions between photogenerated electrons and BQ. For the UV-induced photocatalysis, the suitability of BQ as the scavenger of O2•‒ must be given carefully consideration.


Assuntos
Benzoquinonas , Cromo , Ferro , Oxirredução , Benzoquinonas/química , Cromo/química , Catálise , Ferro/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/efeitos da radiação , Processos Fotoquímicos , Compostos de Nitrogênio/química , Compostos de Nitrogênio/efeitos da radiação , Grafite
3.
Analyst ; 149(8): 2420-2427, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488061

RESUMO

Antimicrobial resistance has become a major global health threat due to the misuse and overuse of antibiotics. Rapid, affordable, and high-efficiency antimicrobial susceptibility testing (AST) is among the effective means to solve this problem. Herein, we developed a capillary-based centrifugal indicator (CBCI) equipped with an in situ culture of pathogenic bacteria for fast AST. The bacterial incubation and growth were performed by macro-incubation, which seamlessly integrated the capillary indicator. Through simple centrifugation, all the bacterial cells were confined at the nanoliter-level capillary column. The packed capillary column height could linearly reflect the bacterial count, and the minimum inhibitory concentration (MIC) was determined based on the difference in the column height between the drug-added groups and the control group. The AST results could easily be determined by the naked eye or smartphone imaging. Thus, the CBCI realized the combination of macro-bacterial incubation and early micro assessment, which accelerated the phenotypic AST without complex microscopic counting or fluorescent labelling. The whole operation process was simple and easy to use. AST results could be determined for E. coli ATCC strains within 3.5 h, and the output results for clinical samples were consistent with the hospital reports. We expect this AST platform to become a useful tool in limiting antimicrobial resistance, especially in remote/resource-limited areas or in underdeveloped countries.


Assuntos
Antibacterianos , Escherichia coli , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Bactérias
4.
ACS Omega ; 9(7): 8464-8470, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38405496

RESUMO

Long noncoding RNA (lncRNA) has been shown to participate in adipogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). In this study, we aimed to investigate the role of lncRNA-LOC646762 in adipogenic differentiation of BMSCs. Transcriptome sequencing revealed a positive correlation between LOC646762 transcription and expression of adipogenic marker genes in adipogenic differentiation. Moreover, LOC646762 overexpression did not negatively impact the cell proliferation of BMSCs. Besides, LOC646762 plays a crucial role in adipogenic differentiation, as evidenced by its positive correlation with adipogenic marker gene expression. Its possible interaction with its proposed target C/EBPß suggests its involvement in essential pathways governing adipogenesis. Collectively, our study outcomes provide valuable insights into the molecular mechanisms underlying the adipogenic differentiation of BMSCs and lay a strong foundation for further research in regenerative medicine.

5.
Int J Oncol ; 64(3)2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38214378

RESUMO

Long­stranded non­coding RNAs (lncRNAs) are RNAs that consist of >200 nucleotides. The majority of lncRNAs do not encode proteins but have been revealed to mediate a variety of important physiological functions. Antisense­lncRNAs (AS­lncRNAs) are transcribed from the opposite strand of a protein or non­protein coding gene as part of the antisense strand of the coding gene. AS­lncRNAs can serve an important role in the tumorigenesis, prognosis, metastasis and drug resistance of a number of malignancies. This has been reported to be exerted through various mechanisms, such as endogenous competition, promoter interactions, direct interactions with mRNAs, acting as 'scaffolds' to regulate mRNA half­life, interactions with 5­untranslated regions and regulation of sense mRNAs. AS­lncRNAs have been found to either inhibit or promote tumor aggressiveness by regulating cell proliferation, energy metabolism, inflammation, inflammatory­carcinoma transformation, invasion, migration and angiogenesis. In addition, accumulating evidence has documented that AS­lncRNAs can regulate tumor therapy resistance. Therefore, targeting aberrantly expressed AS­lncRNAs for cancer treatment may prove to be a promising approach to reverse therapy resistance. In the present review, research advances on the role of AS­lncRNAs in tumor occurrence and development were summarized, with the aim of providing novel ideas for further research in this field.


Assuntos
Neoplasias , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Neoplasias/genética , Regulação Neoplásica da Expressão Gênica
6.
Anal Chim Acta ; 1280: 341872, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37858570

RESUMO

A simple and flexible fabrication method of paper SERS substrate was developed by nanoparticles (NPs) droplet self-assembly at the paper tip with a temperature gradient (PTTG). We turned the drawback of the coffee ring effect into an effective way of preparing paper SERS substrate. When the NPs droplets were continuously dripped onto the PTTG, NPs were densely and uniformly distributed at the paper-tip front based on the combination of gravity and the coffee ring effect, which could achieve 91.2-fold improvement of SERS performance compared to a flat filter paper. Meanwhile, the analytes could also be enriched at the paper-tip front, which could achieve 9.3-fold signal enhancement compared to the paper-tip tail. Thus, the PTTG realized an excellent signal amplification for SERS detection. The paper-tip SERS substrate combined with a portable Raman spectrometer yielded an excellent analytical enhancement factor of 1.15 × 105 with the detection limit of 10 nM Rhodamine 6G (R6G). The whole fabrication procedure was completed within 2 h, and the paper-tip substrate showed a satisfactory substrate-to-substrate reproducibility with a relative standard deviation (RSD) of 5.13% (n = 10). It was successfully applied for quantitatively detecting real samples of oxytetracycline and malachite green with recoveries of 83.84-105.25% (n = 3). Meanwhile, we further evaluated the SERS performance of the PTTG using a laboratory-based Raman spectrometer, and it could realize the detection as low as 10 pM R6G. The proposed paper-tip substrate would offer a promising potential application for the on-site SERS analysis of food safety and environmental health.

7.
Chemosphere ; 344: 140348, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37793551

RESUMO

It has been previously reported that pre-magnetization could enhance the efficacy of zero-valent iron (ZVI) in removing contaminants. However, little is known about the effects and persistence of different magnetization methods on pre-magnetized ZVI (Pre-ZVI) when used in advanced oxidation processes (AOPs). Gaining a comprehensive understanding of the durability of various pre-magnetization methods in enhancing the removal efficiency of different pollutants will significantly impact the widespread utilization of Pre-ZVI in practical engineering. Herein, we investigated the efficiency of dry and wet Pre-ZVI-activated peroxymonosulfate (PMS) in eliminating oxytetracycline (OTC) and evaluated the durability of Pre-ZVI. Additionally, we examined several factors that influence the degradation process's efficiency. Our results found that the reaction constant k values corresponding to the dry Pre-ZVI/PMS system at the pH values of 3, 7, and 9 varied from approximately 0.0384, 0.0331, and 0.0349 (day 1) to roughly 0.0297, 0.0278, and 0.0314 (day 30), respectively. Meanwhile, the wet Pre-ZVI/PMS system exhibited k values ranging from approximately 0.0392, 0.0349, and 0.0374 (day 1) to roughly 0.0380, 0.0291, and 0.0322 (day 30), respectively. Moreover, we proposed four OTC degradation pathways using LC-MS/MS and density functional theory calculations. The toxicity of the degradation products was assessed using the ecological structure activity relationship and the toxicity estimation software tool. Overall, this study provides insights into the application of Pre-ZVI/PMS that can be selectively used to eliminate tetracycline antibiotics from water.


Assuntos
Oxitetraciclina , Poluentes Químicos da Água , Ferro/química , Cromatografia Líquida , Poluentes Químicos da Água/química , Espectrometria de Massas em Tandem
8.
J Pain Res ; 16: 809-819, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36925621

RESUMO

Purpose: To evaluate transcutaneous electrical acupoint stimulation (TEAS) on the perioperative rehabilitation of patients undergoing laparoscopic myomectomy. Patients and Methods: One hundred and five women undergoing laparoscopic hysteromyomectomy were randomly divided into TEAS group (Group T) and control group (Group C). Propofol and remifentanil were used to stabilize patient blood pressure and keep BIS between 40 and 60. Group T patients received TEAS at LI4/PC6 30 minutes before the operation and lasting until the end of anesthesia, followed by TEAS at ST36/SP6 for 30 minutes in PACU. All required indicators were recorded. Results: Group T patients required lower dosages of remifentanil and vasoactive drugs, and had a reduced incidence of propofol injection pain and intraoperative hypotension compared to Group C. Group T also had a lower maximum NRS score in PACU, lower NRS scores at 1 hour and 24 hours, and a lower incidence of vomiting within 24 hours. In addition, the QoR-40 score for Group T at 24 hours after operation was higher in terms of physical comfort, emotional state, pain and total score. Conclusion: TEAS can reduce the amount of anesthetic, maintain hemodynamic stability, reduce postoperative pain, reduce postoperative vomiting, enhance the recovery of gastrointestinal function, increase the quality of postoperative recovery and thus accelerate overall patient recovery.

9.
Front Chem ; 11: 1103792, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36817175

RESUMO

The separation of brines with high Mg/Li mass ratios is a huge challenge. To provide a theoretical basis for the design of separation materials, the hydration of Li+ and Mg2+ in confinement using carbon nanotubes (CNTs) as the 1-D nanopore model was investigated using a multiscale theoretical approach. According to the analysis of the first coordination layer of cations, we determined that the coordination shells of two cations exist inside CNTs, while the second coordination shells of the cations are unstable. Moreover, the results of the structure analysis indicate that the hydration layer of Li+ is not complete in CNTs with diameters of 0.73, 0.87, and 1.00 nm. However, this does not occur in the 0.60 nm CNT, which is explained by the formation of contact ion pairs (CIP) between Li+ and Cl- that go through a unstable solvent-shared ion pair [Li(H2O)4]+, and this research was further extended by 400 ns in the 0.60 nm CNT to address the aforementioned results. However, the hydration layer of Mg2+ is complete and not sensitive to the diameter of CNTs using molecular dynamics simulation and an ab initio molecular dynamics (AIMD) method. Furthermore, the results of the orientation distribution of Li+ and Mg2+ indicate that the water molecules around Mg2+ are more ordered than water molecules around Li+ in the CNTs and are more analogous to the bulk solution. We conclude that it is energetically unfavorable to confine Li+ inside the 0.60-nm diameter CNT, while it is favorable for confining Li+ inside the other four CNTs and Mg2+ in all CNTs, which is driven by the strong electrostatic interaction between cations and Cl-. In addition, the interaction between cations and water molecules in the five CNTs was also analyzed from the non-covalent interaction (NCI) perspective by AIMD.

10.
Anal Chem ; 95(5): 3028-3036, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36688612

RESUMO

We developed a bent-capillary-centrifugal-driven (BCCD) monodisperse droplet generator, which could achieve a perfect combination of driving and segmentation for the dispersed phase only using a rotating bent capillary immersed in the continuous phase (mineral oil). The sample could flow continuously to the bent-capillary outlet to form the droplet precursors, which were segmented into homogeneous droplets in the continuous phase. Through the investigation of influence factors on droplet size and stability, we found that the droplet size could be conveniently controlled by the rotational speed of the bent capillary. The droplet volumes could be adjusted with the range from 34 pL to 1 µL, and the coefficient variations (CVs) were less than 3%. Meanwhile, the BCCD droplet generator could realize the controllable droplet output with a high-efficiency sample utilization of 99.75 ± 1.15%, which offered a significant advantage in reducing the waste of precious samples in the droplet generation process. We validated this system with a digital loop-mediated isothermal amplification (dLAMP) assay for the absolute quantification of Mycobacterium tuberculosis complex nucleic acids. The results demonstrated that the BCCD droplet generator was easy to build, was of low cost, and was convenient to operate, as well as avoided sample loss and cross-contamination by coupling with a 96-well plate. Overall, the present platform, as a simple chip-free droplet generator, will provide an especially valuable droplet generation solution for biochemical applications based on droplets.


Assuntos
Técnicas de Amplificação de Ácido Nucleico , Ácidos Nucleicos , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas de Diagnóstico Molecular , Óleo Mineral
11.
Gut Microbes ; 15(1): 2156764, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36573825

RESUMO

Dysregulation of the gut microbiota by environmental factors is associated with a variety of autoimmune and immune-mediated diseases. In addition, naturally-occurring extracellular antibiotic resistance genes (eARGs) might directly enter the gut via the food chain. However, following gut microbiota exposure to eARGs, the ecological processes shaping the microbiota community assembly, as well as the interplay between the microbiota composition, metabolic function, and the immune responses, are not well understood. Increasing focus on the One Health approach has led to an urgent need to investigate the direct health damage caused by eARGs. Herein, we reveal the significant influence of eARGs on microbiota communities, strongly driven by stochastic processes. How eARGs-stimulate variations in the composition and metabolomic function of the gut microbiota led to cytokine responses in mice of different age and sex were investigated. The results revealed that cytokines were significantly associated with immunomodulatory microbes, metabolites, and ARGs biomarkers. Cytokine production was associated with specific metabolic pathways (arachidonic acid and tryptophan metabolic pathways), as confirmed by ex vivo cytokine responses and recovery experiments in vivo. Furthermore, the gut microbial profile could be applied to accurately predict the degree of intestinal inflammation ascribed to the eARGs (area under the curve = 0.9616). The present study provided a comprehensive understanding of the influence of an eARGs on immune responses and intestinal barrier damage, shedding light on the interplay between eARGs, microbial, metabolites, and the gut antibiotic resistome in modulating the human immune system.


Assuntos
Microbioma Gastrointestinal , Humanos , Animais , Camundongos , Citocinas , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Inflamação
12.
J Colloid Interface Sci ; 626: 221-230, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35792456

RESUMO

The construction of a broad-spectrum photocatalytic system is of great significance for maximizing the utilization of solar energy. Herein, a surface oxygen vacancy triggering high-efficient broad-spectrum BiOCl0.5I0.5 solid solution photocatalyst was successfully fabricated via a one-pot solvothermal process. The UV-vis diffuse reflectance spectra revealed that the introduced oxygen vacancy appears to extend the absorption region of BiOCl0.5I0.5 to a wider wavelength range. Under λ > 580 nm light irradiation for 5 h, nearly 85.6% ciprofloxacin was degraded by BiOCl0.5I0.5 with rich oxygen vacancy, the ciprofloxacin removal efficiency was 3.4 times higher than that with less oxygen vacancy. Moreover, the density functional theory calculations and photoelectrochemical characterizations indicated the excited electrons would preferentially transfer to the new defect level induced by oxygen vacancy, thus greatly reducing the recombination of photogenerated carriers. This work tends to deepen the understanding of defect engineering in steering the construction of broad-spectrum Bi-based solid solution photocatalysts as well as its application in environmental remediation.


Assuntos
Bismuto , Ciprofloxacina , Bismuto/química , Catálise , Ciprofloxacina/química , Oxigênio/química , Luz Solar
13.
J Chromatogr A ; 1676: 463236, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35709605

RESUMO

Alzheimer's disease (AD) is a common neurodegenerative disease. Abnormal glycosylation and phosphorylation modification in AD may be closely related to its pathology. It is of substantial practical significance to simultaneously investigate the roles of phosphorylation and glycosylation in AD. In this work, a bifunctional super-hydrophilic mesoporous nanocomposite (denoted mTiO2@AuCG) was prepared, which combined hydrophilic interaction chromatography (HILIC) and metal oxide affinity chromatography (MOAC) enrichment strategies to enrich phosphopeptides and glycopeptides, respectively or simultaneously. The mTiO2@AuCG exhibited excellent performance on the high-efficiency enrichment of glycopeptides (selectivity, 5000:1 molar ratios of BSA/HRP; sensitivity, 0.1 fmol HRP; satisfactory recovery rate; loading capacity, 200 mg/g) and phosphopeptides (selectivity, 1000:1 molar ratios of BSA/ß-casein; sensitivity, 0.2 fmol ß-casein; satisfactory recovery rate; loading capacity, 200 mg/g). Using these advantages, after single-step enrichment of mTiO2@AuCG, a total of 209 glycopeptides related to 93 glycoproteins, and 17 phosphopeptides related to 13 phosphoproteins were detected from normal human serum. By contrast, 167 glycopeptides related to 88 glycoproteins, and 14 phosphopeptides related to 12 phosphoproteins were found in AD serum.


Assuntos
Doença de Alzheimer , Nanocompostos , Doenças Neurodegenerativas , Caseínas , Glicopeptídeos/química , Glicoproteínas , Glicosilação , Humanos , Interações Hidrofóbicas e Hidrofílicas , Fosfopeptídeos/química , Fosforilação
14.
J Chromatogr A ; 1669: 462929, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35279555

RESUMO

A novel ultra-hydrophilic zwitterionic-HILIC (ZIC-HILIC) nanosphere (Fe3O4-CG) was synthesized via a one-step hydrothermal strategy, which significantly simplified the conventional multi-step procedures for the preparation of ZIC-HILIC materials. The dual-functional Fe3O4-CG nanosphere exhibited excellent selectivity (molar ratio BSA:HRP = 5000:1), low detection limit (0.05 fmol/µL), satisfactory reusability (at least 5 times) and recovery rate (93.7 ± 2.1%). The binding constant of Fe3O4-CG for HRP is 2.45 ± 0.32 × 10-6 M and the theoretical binding capacity is 330 mg g-1. In addition, the Fe3O4-CG microsphere showed excellent performance in the detection of glycopeptides from real biological samples. Furthermore, 131 glycopeptides related to 71 glycoproteins were selectively enriched from healthy human serum and 180 glycopeptides related to 82 glycoproteins were captured from Alzheimer's disease patients' serum analyzed by Nano-LC-MS/MS. Gene ontology analysis of the biological process and molecular function showed that 21 primitive glycoproteins in glycopeptides captured from Alzheimer's disease patients' serum were meaningfully involved in a variety of neurodegenerative disease-related events, including serine-type endopeptidase inhibitor activity, receptor binding, positive regulation of B cell activation, and platelet activation.


Assuntos
Doença de Alzheimer , Nanosferas , Doenças Neurodegenerativas , Glicopeptídeos/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Fenômenos Magnéticos , Espectrometria de Massas em Tandem
15.
Nano Lett ; 22(4): 1595-1603, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35133850

RESUMO

Optical beam steerers have been widely employed for information acquisitions. Numerous beam steering schemes have been developed, and each of them can satisfy practical requirements for certain scenarios. However, there is still a lack of a comprehensive approach that is able to balance all of the critical technical parameters for wide range of applications. Here, a semisolid micromechanical beam steering system based on micrometa-lens arrays (MMLAs) is demonstrated. It is operated by manipulating the probe beam over two sets of decentered MMLAs potentially driven by high-speed piezo-electric motors. Small f-numbers, well-corrected aberration, and easy lateral reproduction of micrometa-lenses optimize the overall technical parameters. As a proof-of-concept, we implement such a device exhibiting diffraction-limited resolution within a large field of view of 30° × 30°. A three-dimensional depth sensing is also performed to demonstrate its potential in light detection and ranging applications.


Assuntos
Lentes , Desenho de Equipamento , Análise de Falha de Equipamento
16.
Gut Microbes ; 14(1): 2022442, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35030982

RESUMO

Diet can not only provide nutrition for intestinal microbiota, it can also remodel them. However, is unclear whether and how diet affects the spread of antibiotic resistance genes (ARGs) in the intestinal microbiota. Therefore, we employed selected high-sugar, high-fat, high-protein, and normal diets to explore the effect. The results showed that high-sugar, high-fat, and high-protein diets promoted the amplification and transfer of exogenous ARGs among intestinal microbiota, and up-regulated the expression of trfAp and trbBp while significantly altered the intestinal microbiota and its metabolites. Inflammation-related products were strongly correlated with the spread of ARGs, suggesting the intestinal microenvironment after diet remodeling might be conducive to the spreading of ARGs. This may be attributed to changes in bacterial membrane permeability, the SOS response, and bacterial composition and diversity caused by diet-induced inflammation. In addition, acceptor bacteria (zygotes) screened by flow cytometry were mostly Proteobacteria, Firmicutes and Actinobacteria, and most were derived from dominant intestinal bacteria remodeled by diet, indicating that the transfer of ARGs was closely linked to diet, and had some selectivity. Metagenomic results showed that the gut resistance genome could be affected not only by diet, but by exogenous antibiotic resistant bacteria (ARB). Many ARG markers coincided with bacterial markers in diet groups. Therefore, dominant bacteria in different diets are important hosts of ARGs in specific dietary environments, but the many pathogenic bacteria present may cause serious harm to human health.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/genética , Gorduras na Dieta/metabolismo , Proteínas Alimentares/metabolismo , Açúcares da Dieta/metabolismo , Farmacorresistência Bacteriana , Microbioma Gastrointestinal , Animais , Bactérias/classificação , Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/análise , Proteínas Alimentares/efeitos adversos , Proteínas Alimentares/análise , Açúcares da Dieta/efeitos adversos , Açúcares da Dieta/análise , Amplificação de Genes , Transferência Genética Horizontal , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C
17.
J Colloid Interface Sci ; 610: 518-526, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34863551

RESUMO

Owing to the exorbitant CO2 activation energy and unsatisfactory photogenerated charge separation efficiency, CO2 photoconversion still faces enormous challenges. In this study, a directional electron transfer channel has been established by decorating N-doped carbon quantum dots (N-CQDs) on the surface of Bi4MoO9 nanoparticles to ensure that more active electrons can participate in the CO2 reduction. The conduction band of Bi4MoO9 nanoparticles is calculated to be -1.55 eV versus the normal hydrogen electrode (NHE), pH = 7, which is negative enough to attain the photocatalytic CO2 reduction potential of -0.53 eV versus NHE, pH = 7. CO2 adsorption curves and in situ Fourier transform infrared spectra reveal that N-CQDs facilitate surface CO2 adsorption and activation, as well as CO desorption. In addition, steady-state photoluminescence and photoelectrochemical tests prove that the charge separation efficiency can be greatly enhanced by constructing N-CQDs/Bi4MoO9 composites. In the presence of pure water, N-CQDs/Bi4MoO9-2 composite achieved a CO yield of 16.22 µmol g-1 after 5 h Xe light illumination, which was 3.24 times higher than that of pure Bi4MoO9 (4.98 µmol g-1). This study offers a distinctive approach to the optimization of Bi4MoO9 photocatalysts and their application in energy conversion.

18.
J Hazard Mater ; 425: 127942, 2022 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-34902725

RESUMO

Antibiotic resistance genes (ARGs) are receiving increasing concerns due to the antibiotic resistance crisis. Nevertheless, little is known about the spatial behavior and sources of extracellular ARGs (eARGs) in the chlorinated drinking water distribution systems (DWDSs). Here, tap water was continuously collected to reveal the occurrence of both eARGs and intracellular ARGs (iARGs) along a chlorinated DWDS. Afterward, the correlation between eARGs, eDNA-releasing communities, and communities of planktonic bacteria was further analyzed. The eARG concentration decreased significantly, whereas the proportion of vanA and blaNDM-1 increased. Further, the diversity of the eDNA-releasing community increased markedly with increasing distance from the drinking water treatment plant (DWTP). Moreover, the dominant eDNA-releasing bacteria shifted from Acinetobacter, Pseudomonas, and Methylobacterium-Methylorubrum in finished water from the DWTP to Bacteroides, Faecalibacterium, Staphylococcus, and Parabacteroides in the DWDS. In terms of eARG source, thirty genera were significantly correlated with seven types of eARGs that resulted from the lysis of dead planktonic bacteria and detached biofilms. Conversely, the iARGs concentration increased, whereas the biodiversity of the planktonic bacteria community decreased in the sampling points along the DWDSs. Our findings provide critical insights into the spatial behavior and sources of eARGs, highlighting the health risks associated with ARGs in DWDSs.


Assuntos
Água Potável , Purificação da Água , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Comportamento Espacial , Águas Residuárias
19.
Dalton Trans ; 50(42): 15084-15093, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34610067

RESUMO

The nickel-catalyzed hydrocarboxylation of alkenes using carbon dioxide has recently become an appealing method to prepare functionalized carboxylic acids with high efficiency and regioselectivity. Herein, density functional theory (DFT) calculations were conducted on the Ni-catalyzed hydrocarboxylation of aryl-/alkyl-substituted alkenes with CO2. The α- and ß-carboxylation of aromatic and aliphatic olefins originate from distinct catalytic cycles: H-transfer-carboxylation and carboxylation-H-transfer pathways. The typical hydrometallation-carboxylation mechanism is unlikely because water/carbonic acid (H-resource) are inferior hydride donors.

20.
Front Cell Infect Microbiol ; 11: 654074, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222037

RESUMO

An unhealthy diet has been linked to increased incidence of chronic diseases. To investigate the relationship between diet and intestinal inflammation, mice in two experimental groups were fed on a high-fat diet or high-fructose diet, respectively. The result showed that the defecation volume of the experimental groups was significantly reduced compared with that of the control group, and the levels of pro-inflammatory cytokines (interleukin (IL)-1ß and IL-6) and IgG in serum were increased significantly. In addition, inflammatory cell infiltration was observed in intestinal tissue, indicating that a high-fructose or high-fat diet can lead to constipation and inflammation. Further analysis showed that the microbial composition of the experimental groups changed significantly, including a decrease of the Bacteroidetes/Firmicutes ratio and increased levels of Bacteroides, Akkermansia, Lactobacillus, and Ruminococcus, which might be associated with inflammation. The results of pro-inflammatory metabolites analysis showed that the levels of arachidonic acid, stearic acid, and indoxylsulfuric acid were significantly increased in the experimental groups, which were related significantly to Bacteroides, Enterococcus, and Akkermansia. Meanwhile, the content of 5-hydroxytryptamine (5-HT) was significantly decreased, which might cause constipation by reducing intestinal peristalsis. Moreover, transplantation of fecal bacteria from inflammatory mice caused constipation and inflammation in normal mice, which could be relieved by feeding a normal diet. The results of the present study indicated that changes in intestinal microbiota and microbial metabolites may underlie chronic intestinal inflammation and constipation caused by high-fructose and high-fat diets.


Assuntos
Dieta Hiperlipídica , Microbioma Gastrointestinal , Animais , Dieta Hiperlipídica/efeitos adversos , Firmicutes , Frutose , Inflamação , Camundongos , Camundongos Endogâmicos C57BL
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