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1.
J Am Chem Soc ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869216

RESUMO

Understanding the interfacial hydrogen evolution reaction (HER) is crucial to regulate the electrochemical behavior in aqueous zinc batteries. However, the mechanism of HER related to solvation chemistry remains elusive, especially the time-dependent dynamic evolution of the hydrogen bond (H-bond) under an electric field. Herein, we combine in situ spectroscopy with molecular dynamics simulation to unravel the dynamic evolution of the interfacial solvation structure. We find two critical change processes involving Zn-electroplating/stripping, including the initial electric double layer establishment to form an H2O-rich interface (abrupt change) and the subsequent dynamic evolution of an H-bond (gradual change). Moreover, the number of H-bonds increases, and their strength weakens in comparison with the bulk electrolyte under bias potential during Zn2+ desolvation, forming a diluted interface, resulting in massive hydrogen production. On the contrary, a concentrated interface (H-bond number decreases and strength enhances) is formed and produces a small amount of hydrogen during Zn2+ solvation. The insights on the above results contribute to deciphering the H-bond evolution with competition/corrosion HER during Zn-electroplating/stripping and clarifying the essence of electrochemical window widened and HER suppression by high concentration. This work presents a new strategy for aqueous electrolyte regulation by benchmarking the abrupt change of the interfacial state under an electric field as a zinc performance-enhancement criterion.

2.
Angew Chem Int Ed Engl ; 63(17): e202400254, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38441399

RESUMO

Acting as a passive protective layer, solid-electrolyte interphase (SEI) plays a crucial role in maintaining the stability of the Li-metal anode. Derived from the reductive decomposition of electrolytes (e.g., anion and solvent), the SEI construction presents as an interfacial process accompanied by the dynamic de-solvation process during Li-metal plating. However, typical electrolyte engineering and related SEI modification strategies always ignore the dynamic evolution of electrolyte configuration at the Li/electrolyte interface, which essentially determines the SEI architecture. Herein, by employing advanced electrochemical in situ FT-IR and MRI technologies, we directly visualize the dynamic variations of solvation environments involving Li+-solvent/anion. Remarkably, a weakened Li+-solvent interaction and anion-lean interfacial electrolyte configuration have been synchronously revealed, which is difficult for the fabrication of anion-derived SEI layer. Moreover, as a simple electrochemical regulation strategy, pulse protocol was introduced to effectively restore the interfacial anion concentration, resulting in an enhanced LiF-rich SEI layer and improved Li-metal plating/stripping reversibility.

3.
Angew Chem Int Ed Engl ; 63(5): e202316112, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38088222

RESUMO

Compensating the irreversible loss of limited active lithium (Li) is essentially important for improving the energy-density and cycle-life of practical Li-ion battery full-cell, especially after employing high-capacity but low initial coulombic efficiency anode candidates. Introducing prelithiation agent can provide additional Li source for such compensation. Herein, we precisely implant trace Co (extracted from transition metal oxide) into the Li site of Li2 O, obtaining (Li0.66 Co0.11 □0.23 )2 O (CLO) cathode prelithiation agent. The synergistic formation of Li vacancies and Co-derived catalysis efficiently enhance the inherent conductivity and weaken the Li-O interaction of Li2 O, which facilitates its anionic oxidation to peroxo/superoxo species and gaseous O2 , achieving 1642.7 mAh/g~Li2O prelithiation capacity (≈980 mAh/g for prelithiation agent). Coupled 6.5 wt % CLO-based prelithiation agent with LiCoO2 cathode, substantial additional Li source stored within CLO is efficiently released to compensate the Li consumption on the SiO/C anode, achieving 270 Wh/kg pouch-type full-cell with 92 % capacity retention after 1000 cycles.

4.
Adv Mater ; 36(1): e2308656, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37955857

RESUMO

Raising the charging cut-off voltage of layered oxide cathodes can improve their energy density. However, it inevitably introduces instabilities regarding both bulk structure and surface/interface. Herein, exploiting the unique characteristics of high-valence Nb5+ element, a synchronous surface-to-bulk-modified LiCoO2 featuring Li3 NbO4 surface coating layer, Nb-doped bulk, and the desired concentration gradient architecture through one-step calcination is achieved. Such a multifunctional structure facilitates the construction of high-quality cathode/electrolyte interface, enhances Li+ diffusion, and restrains lattice-O loss, Co migration, and associated layer-to-spinel phase distortion. Therefore, a stable operation of Nb-modified LiCoO2 half-cell is achieved at 4.6 V (90.9% capacity retention after 200 cycles). Long-life 250 Wh kg-1 and 4.7 V-class 550 Wh kg-1 pouch cells assembled with graphite and thin Li anodes are harvested (both beyond 87% after 1600 and 200 cycles). This multifunctional one-step modification strategy establishes a technological paradigm to pave the way for high-energy density and long-life lithium-ion cathode materials.

5.
Adv Mater ; 36(13): e2312159, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38117030

RESUMO

Developing sacrificial cathode prelithiation technology to compensate for active lithium loss is vital for improving the energy density of lithium-ion battery full-cells. Li2CO3 owns high theoretical specific capacity, superior air stability, but poor conductivity as an insulator, acting as a promising but challenging prelithiation agent candidate. Herein, extracting a trace amount of Co from LiCoO2 (LCO), a lattice engineering is developed through substituting Li sites with Co and inducing Li defects to obtain a composite structure consisting of (Li0.906Co0.043▫0.051)2CO2.934 and ball milled LiCoO2 (Co-Li2CO3@LCO). Notably, both the bandgap and Li─O bond strength have essentially declined in this structure. Benefiting from the synergistic effect of Li defects and bulk phase catalytic regulation of Co, the potential of Li2CO3 deep decomposition significantly decreases from typical >4.7 to ≈4.25 V versus Li/Li+, presenting >600 mAh g-1 compensation capacity. Impressively, coupling 5 wt% Co-Li2CO3@LCO within NCM-811 cathode, 235 Wh kg-1 pouch-type full-cell is achieved, performing 88% capacity retention after 1000 cycles.

6.
Angew Chem Int Ed Engl ; 63(6): e202316790, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38116869

RESUMO

Electrolyte engineering is a fascinating choice to improve the performance of Li-rich layered oxide cathodes (LRLO) for high-energy lithium-ion batteries. However, many existing electrolyte designs and adjustment principles tend to overlook the unique challenges posed by LRLO, particularly the nucleophilic attack. Here, we introduce an electrolyte modification by locally replacing carbonate solvents in traditional electrolytes with a fluoro-ether. By benefit of the decomposition of fluoro-ether under nucleophilic O-related attacks, which delivers an excellent passivation layer with LiF and polymers, possessing rigidity and flexibility on the LRLO surface. More importantly, the fluoro-ether acts as "sutures", ensuring the integrity and stability of both interfacial and bulk structures, which contributed to suppressing severe polarization and enhancing the cycling capacity retention from 39 % to 78 % after 300 cycles for the 4.8 V-class LRLO. This key electrolyte strategy with comprehensive analysis, provides new insights into addressing nucleophilic challenge for high-energy anionic redox related cathode systems.

7.
Sensors (Basel) ; 23(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38139495

RESUMO

As an important component connecting the upper and lower structures of a bridge, bridge bearings can reliably transfer vertical and horizontal loads to a foundation. Bearing capacity needs to be monitored during construction and maintenance. To create an intelligent pot bearing, a portable small spot welding machine is used to weld pipe-type welding strain gauges to the pot bearing to measure strain and force values. The research contents of this paper include the finite element analysis of a basin bearing, optimal arrangement of welding strain gauges, calibration testing, and temperature compensation testing of the intelligent basin bearing of the welding strain gauges. Polynomial fitting is used for the fitting and analysis of test data. The results indicate that the developed intelligent pot bearing has a high-precision force measurement function and that after temperature compensation, the measurement error is within 1.8%. The intelligent pot bearing has a low production cost, and the pipe-type welding strain gauges can be conveniently replaced. The novelty is that the bearing adopts a robust pipe-type welding strain gauge and that automatic temperature compensation is used. Therefore, the research results have excellent engineering application value.

8.
Medicine (Baltimore) ; 102(47): e36119, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38013320

RESUMO

Apoptosis of skin keratinocytes is closely associated with skin problems in humans and natural flavonoids have shown excellent biological activity. Hence, the study of flavonoids against human keratinocyte apoptosis has aroused the interest of numerous researchers. In this study, methyl thiazolyl tetrazolium (MTT) assay and Western blots were used to investigate the skin-protective effect of isoviolanthin, a di-C-glycoside derived from Dendrobium officinale, on hydrogen peroxide (H2O2)-triggered apoptosis of skin keratinocytes. Transcriptome sequencing (RNA-Seq) was used to detect the altered expression genes between the model and treatment group and qRT-PCR was used to verify the accuracy of transcriptome sequencing results. Finally, molecular docking was used to observe the binding ability of isoviolanthin to the selected differential genes screened by transcriptome sequencing. Our results found isoviolanthin could probably increase skin keratinocyte viability, by resisting against apoptosis of skin keratinocytes through downregulating the level of p53 for the first time. By comparing transcriptome differences between the model and drug administration groups, a total of 2953 differential expression genes (DEGs) were identified. Enrichment analysis showed that isoviolanthin may regulate these pathways, such as DNA replication, Mismatch repair, RNA polymerase, Fanconi anemia pathway, Cell cycle, p53 signaling pathway. Last, our results found isoviolanthin has a strong affinity for binding to KDM6B, CHAC2, ESCO2, and IPO4, which may be the potential target for treating skin injuries induced by reactive oxide species. The current study confirms isoviolanthin potential as a skin protectant. The findings may serve as a starting point for further research into the mechanism of isoviolanthin protection against skin damage caused by reactive oxide species (e.g., hydrogen peroxide).


Assuntos
Peróxido de Hidrogênio , Transcriptoma , Humanos , Peróxido de Hidrogênio/farmacologia , Simulação de Acoplamento Molecular , Proteína Supressora de Tumor p53/metabolismo , Queratinócitos , Flavonoides/metabolismo , Apoptose , Acetiltransferases/metabolismo , Acetiltransferases/farmacologia , Proteínas Cromossômicas não Histona/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo
9.
Small ; 19(50): e2303929, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37621028

RESUMO

Both LiFePO4 (LFP) and NaFePO4 (NFP) are phosphate polyanion-type cathode materials, which have received much attention due to their low cost and high theoretical capacity. Substitution of manganese (Mn) elements for LFP/NFP materials can improve the electrochemical properties, but the connection between local structural changes and electrochemical behaviors after Mn substitution is still not clear. This study not only achieves improvements in energy density of LFP and cyclic stability of NFP through Mn substitution, but also provides an in-depth analysis of the structural evolutions induced by the substitution. Among them, the substitution of Mn enables LiFe0.5 Mn0.5 PO4 to achieve a high energy density of 535.3 Wh kg-1 , while NaFe0.7 Mn0.3 PO4 exhibits outstanding cyclability with 89.6% capacity retention after 250 cycles. Specifically, Mn substitution broadens the ion-transport channels, improving the ion diffusion coefficient. Moreover, LiFe0.5 Mn0.5 PO4 maintains a more stable single-phase transition during the charge/discharge process. The transition of NaFe0.7 Mn0.3 PO4 to the amorphous phase is avoided, which can maintain structural stability and achieve better electrochemical performance. With systematic analysis, this research provides valuable guidance for the subsequent design of high-performance polyanion-type cathodes.

10.
J Phys Chem Lett ; 14(19): 4565-4574, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37161991

RESUMO

Cathode electrolyte interphase (CEI) layers derived from electrolyte oxidative decomposition can passivate the cathode surface and prevent its direct contact with electrolyte. The inorganics-dominated inner solid electrolyte layer (SEL) and organics-rich outer quasi-solid-electrolyte layer (qSEL) constitute the CEI layer, and both merge at the junction without a clear boundary, which assures the CEI layer with both ionic-conducting and electron-blocking properties. However, the typical "wash-then-test" pattern of characterizations aiming at the microstructure of CEI layers would dissolve the qSEL and even destroy the SEL, leading to an overanalysis of electrolyte decomposition pathway and misassignment of CEI architecture (e.g., component and morphology). In this study, we established a full-dimensional characterization paradigm (combining Fourier transform infrared, solution NMR, X-ray photoelectron spectroscopy, and mass spectrometry technologies) and reconstructed the original CEI layer model. Besides, the feasibility of this characterization paradigm has been verified in a wide operating voltage range on a typical LiNixMnyCozO2 cathode.

11.
Nano Lett ; 23(8): 3565-3572, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37026665

RESUMO

The prominent problem with graphite anodes in practical applications is the detrimental Li plating, resulting in rapid capacity fade and safety hazards. Herein, secondary gas evolution behavior during the Li-plating process was monitored by online electrochemical mass spectrometry (OEMS), and the onset of local microscale Li plating on the graphite anode was precisely/explicitly detected in situ/operando for early safety warnings. The distribution of irreversible capacity loss (e.g., primary and secondary solid electrolyte interface (SEI), dead Li, etc.) under Li-plating conditions was accurately quantified by titration mass spectroscopy (TMS). Based on OEMS/TMS results, the effect of typical VC/FEC additives was recognized at the level of Li plating. The nature of vinylene carbonate (VC)/fluoroethylene carbonate (FEC) additive modification is to enhance the elasticity of primary and secondary SEI by adjusting organic carbonates and/or LiF components, leading to less "dead Li" capacity loss. Though VC-containing electrolyte greatly suppresses the H2/C2H4 (flammable/explosive) evolution during Li plating, more H2 is released from the reductive decomposition of FEC.

12.
Chem Sci ; 14(8): 2183-2191, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36845937

RESUMO

Anode-free lithium metal batteries (AF-LMBs) can deliver the maximum energy density. However, achieving AF-LMBs with a long lifespan remains challenging because of the poor reversibility of Li+ plating/stripping on the anode. Here, coupled with a fluorine-containing electrolyte, we introduce a cathode pre-lithiation strategy to extend the lifespan of AF-LMBs. The AF-LMB is constructed with Li-rich Li2Ni0.5Mn1.5O4 cathodes as a Li-ion extender; the Li2Ni0.5Mn1.5O4 can deliver a large amount of Li+ in the initial charging process to offset the continuous Li+ consumption, which benefits the cycling performance without sacrificing energy density. Moreover, the cathode pre-lithiation design has been practically and precisely regulated using engineering methods (Li-metal contact and pre-lithiation Li-biphenyl immersion). Benefiting from the highly reversible Li metal on the Cu anode and Li2Ni0.5Mn1.5O4 cathode, the further fabricated anode-free pouch cells achieve 350 W h kg-1 energy density and 97% capacity retention after 50 cycles.

13.
Nano Lett ; 22(24): 9972-9981, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36512422

RESUMO

Development of high-energy-density rechargeable battery systems not only needs advanced qualitative characterizations for mechanism exploration but also requires accurate quantification technology to quantitatively elucidate products and fairly assess numerous modification strategies. Herein, as a reliable quantification technology, titration mass spectroscopy (TMS) is developed to accurately quantify O-related anionic redox reactions (Li-O2 battery and nickel-cobalt-manganese (NCM)/Li-rich cathodes), parasitic carbonate deposition and decomposition (derived from air-exposure degradation and electrolyte oxidation), and dead Li0 formation (Li-metal battery and over-discharged graphite anode). TMS technology can harvest key information on products (e.g., quantification of oxidized lattice oxygen and solid electrolyte interphase (SEI)/cathode electrolyte interphase (CEI) components) and guide corresponding design strategy by enhancing understanding of the mechanism (e.g., clearly distinguish the catalytic target of highly oxidative Ni4+ on the NCM cathode). Not limited as a rigid quantification tool for widely known products/mechanisms, TMS technology has been demonstrated as a powerful and versatile tool for the investigations of advanced batteries.

14.
Nano Lett ; 22(12): 4985-4992, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35686884

RESUMO

As a full cell system with attractive theoretical energy density, challenges faced by Li-O2 batteries (LOBs) are not only the deficient actual capacity and superoxide-derived parasitic reactions on the cathode side but also the stability of Li-metal anode. To solve simultaneously intrinsic issues, multifunctional fluorinated graphene (CFx, x = 1, F-Gr) was introduced into the ether-based electrolyte of LOBs. F-Gr can accelerate O2- transformation and O2--participated oxygen reduction reaction (ORR) process, resulting in enhanced discharge capacity and restrained O2--derived side reactions of LOBs, respectively. Moreover, F-Gr induced the F-rich and O-depleted solid electrolyte interphase (SEI) film formation, which have improved Li-metal stability. Therefore, energy storage capacity, efficiency, and cyclability of LOBs have been markedly enhanced. More importantly, the method developed in this work to disperse F-Gr into an ether-based electrolyte for improving LOBs' performances is convenient and significant from both scientific and engineering aspects.

15.
Int J Anal Chem ; 2021: 7109383, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34349801

RESUMO

BACKGROUND: This study aimed to explore the zearalenone (ZEN) immunogen synthesis method, immunogenicity, and antibody characteristics and to lay a foundation for the establishment of immunoassay methods for ZEN single residue and ZEN and its analogs total residue. METHODS: Based on the molecular structure and active sites of ZEN, oxime active ester (OAE), condensation mixed anhydride (CMA), formaldehyde (FA), and 1,4-butanediol diglycidyl ether method (BDE) were designed and used for immunogen (ZEN-BSA) synthesis. The immunogens were identified by infrared (IR) and ultraviolet (UV) spectra and gel electrophoresis (SDS-PAGE) and were then used to immunize Balb/c mice to prepare ZEN polyclonal antibody (ZEN pAb). The titers and sensitivity of the ZEN pAb were determined by indirect noncompetitive ELISA (inELISA) and indirect competitive ELISA (icELISA), respectively, and its specificity was assessed by the cross-reaction test (CR). RESULTS: ZEN-BSA was successfully synthesized, and the molecular binding ratios of ZEN to BSA were 17.2 : 1 (OAE), 14.6 : 1 (CMA), 9.7 : 1 (FA), and 8.3 : 1 (BDE), respectively. The highest inELISA titers of ZEN pAb of each group were 1 : (6.4 × 103) (OAE), 1 : (3.2 × 103) (CMA), 1 : (1.6 × 103) (FA), and 1 : (1.6 × 103) (BDE), respectively. The 50% inhibition concentrations (IC50) for ZEN by icELISA of each group were 11.67 µg/L (OAE), 16.29 µg/L (CMA), 20.92 µg/L (FA) and 24.36 µg/L (BDE), respectively. ZEN pAb from the mice immunized with ZEN-BSA (OAE) and ZEN-BSA (CMA) had class broad specificity to ZEN and its analogs. The CRs of ZEN pAb with α-ZAL, ß-ZAL, α-ZOL, ß-ZOL, and ZON were 36.53%, 16.98%, 64.33%, 20.16%, and 10.66%, respectively. ZEN pAb from the mice immunized with ZEN-BSA (FA) and ZEN-BSA (BDE) had high specificity for ZEN. The CRs of ZEN pAb with its analogs were all less than 1.0%. CONCLUSION: This study demonstrated that the preparation of the class broad-specificity antibodies of ZEN and its analogs can be achieved by immunizing animals with the immunogen ZEN-BSA prepared by the OAE method, while the preparation of highly specific antibodies can be achieved by immunizing animals with the immunogen ZEN-BSA prepared by the FA method. These findings lay the material and technical foundation for immunoassay of ZEN single residue and ZEN and its analogs total residue.

16.
Toxins (Basel) ; 13(6)2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34071768

RESUMO

This study aimed to detect and monitor total Zearalenone (ZEN) and its five homologs (ZENs) in cereals and feed. The monoclonal antibodies (mAbs) with a high affinity and broad class specificity against ZENs were prepared, and the conditions of a heterologous indirect competitive ELISA (icELISA) were preliminarily optimized based on the ZEN mAbs. The immunogen ZEN-BSA was synthesized using the oxime active ester method (OAE) and identified using infrared (IR) and ultraviolet (UV). The coating antigen ZEN-OVA was obtained via the 1,4-butanediol diglycidyl ether method (BDE). Balb/c mice were immunized using a high ZEN-BSA dose with long intervals and at multiple sites. A heterologous indirect non-competitive ELISA (inELISA) and an icELISA were used to screen the suitable cell fusion mice and positive hybridoma cell lines. The ZEN mAbs were prepared by inducing ascites in vivo. The standard curve was established, and the sensitivity and specificity of the ZEN mAbs were determined under the optimized icELISA conditions. ZEN-BSA was successfully synthesized at a conjugation ratio of 17.2:1 (ZEN: BSA). Three hybridoma cell lines, 2D7, 3C2, and 4A10, were filtered, and their mAbs corresponded to an IgG1 isotype with a κ light chain. The mAbs titers were between (2.56 to 5.12) × 102 in supernatants and (1.28 to 5.12) × 105 in the ascites. Besides, the 50% inhibitive concentration (IC50) values were from 18.65 to 31.92 µg/L in the supernatants and 18.12 to 31.46 µg/L in the ascites. The affinity constant (Ka) of all of the mAbs was between 4.15 × 109 and 6.54 × 109 L/mol. The IC50 values of mAb 2D7 for ZEN, α-ZEL, ß-ZEL, α-ZAL, ß-ZAL and ZAN were 17.23, 16.71, 18.27, 16.39, 20.36 and 15.01 µg/L, and their cross-reactivities (CRs, %) were 100%, 103.11%, 94.31%, 105.13%, 84.63%, and 114.79%, respectively, under the optimized icELISA conditions. The limit of detection (LOD) for ZEN was 0.64 µg/L, and its linear working range was between 1.03 and 288.55 µg/L. The mAbs preparation and the optimization of icELISA conditions promote the potential development of a rapid test ELISA kit, providing an alternative method for detecting ZEN and its homologs in cereals and feed.


Assuntos
Anticorpos Monoclonais/biossíntese , Afinidade de Anticorpos , Especificidade de Anticorpos , Zearalenona/imunologia , Animais , Anticorpos Monoclonais/imunologia , Linhagem Celular , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Soroalbumina Bovina/imunologia , Zearalenona/análise , Zearalenona/metabolismo
17.
Molecules ; 25(18)2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32916811

RESUMO

Aflatoxin (AF) contamination is a major concern in the food and feed industry because of its prevalence and toxicity. Improved aflatoxin detection methods are still needed. Immunoassays are an important method for total aflatoxin (TAF) analysis in food due to its technical advantages such as high specificity, sensitivity, and simplicity, but require high-quality antibodies. Here, we first review the three ways to prepare high-quality antibodies for TAF immunoassay, second, compare the advantages and disadvantages of antigen synthesis methods for B-group and G-group aflatoxins, and third, describe the status of novel genetic engineering antibodies. This review can provide new methods and ideas for the development of TAF immunoassays.


Assuntos
Aflatoxinas/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Imunoensaio/métodos , Animais , Anticorpos Monoclonais/biossíntese , Inocuidade dos Alimentos , Humanos , Camundongos , Sensibilidade e Especificidade , Zea mays
18.
J Infect ; 81(1): e1-e5, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32171872

RESUMO

BACKGROUND: Corona Virus Disease 2019 (COVID-19) due to the 2019 novel coronavirus (SARS-CoV-2) emerged in Wuhan city and rapidly spread throughout China. We aimed to compare arbidol and lopinavir/ritonavir(LPV/r) treatment for patients with COVID-19 with LPV/r only. METHODS: In this retrospective cohort study, we included adults (age≥18years) with laboratory-confirmed COVID-19 without Invasive ventilation, diagnosed between Jan 17, 2020, and Feb 13, 2020. Patients, diagnosed after Jan 17, 2020, were given oral arbidol and LPV/r in the combination group and oral LPV/r only in the monotherapy group for 5-21 days. The primary endpoint was a negative conversion rate of coronavirus from the date of COVID-19 diagnosis(day7, day14), and assessed whether the pneumonia was progressing or improving by chest CT (day7). RESULTS: We analyzed 16 patients who received oral arbidol and LPV/r in the combination group and 17 who oral LPV/r only in the monotherapy group, and both initiated after diagnosis. Baseline clinical, laboratory, and chest CT characteristics were similar between groups. The SARS-CoV-2 could not be detected for 12(75%) of 16 patients' nasopharyngeal specimens in the combination group after seven days, compared with 6 (35%) of 17 in the monotherapy group (p < 0·05). After 14 days, 15 (94%) of 16 and 9 (52·9%) of 17, respectively, SARS-CoV-2 could not be detected (p < 0·05). The chest CT scans were improving for 11(69%) of 16 patients in the combination group after seven days, compared with 5(29%) of 17 in the monotherapy group (p < 0·05). CONCLUSION: In patients with COVID-19, the apparent favorable clinical response with arbidol and LPV/r supports further LPV/r only.


Assuntos
Antivirais/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Indóis/uso terapêutico , Lopinavir/uso terapêutico , Pneumonia Viral/tratamento farmacológico , Ritonavir/uso terapêutico , Administração Oral , Adulto , Antivirais/administração & dosagem , COVID-19 , Estudos de Coortes , Infecções por Coronavirus/diagnóstico por imagem , Combinação de Medicamentos , Quimioterapia Combinada , Feminino , Humanos , Indóis/administração & dosagem , Lopinavir/administração & dosagem , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico por imagem , Estudos Retrospectivos , Ritonavir/administração & dosagem , Tomografia Computadorizada por Raios X
19.
J Ovarian Res ; 12(1): 60, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31277702

RESUMO

OBJECTIVE: To investigate whether miR-203a-3p can regulate the biological behaviors of ovarian cancer cells by targeting ATM to affect the Akt/GSK-3ß/Snail signaling pathway. METHODS: The expression levels of miR-203a-3p and ATM were detected by qRT-PCR, immunohistochemical staining and Western blotting in ovarian cancer tissues and adjacent normal tissues obtained from 152 subjects. A dual-luciferase reporter gene assay was performed to verify the relationship between miR-203a-3p and ATM. Human ovarian cancer cell lines (A2780 and SKOV3) were used to generate the Blank, miR-NC, miR-203a-3p mimic, Control siRNA, ATM siRNA, and miR-203a-3p inhibitor + ATM siRNA groups. The biological behaviors of ovarian cancer cells were evaluated by CCK-8, wound healing, and Transwell invasion assays, annexin V-FITC/PI staining and flow cytometry. The levels of Akt/GSK-3ß/Snail pathway-related proteins were assessed by Western blotting. RESULTS: Ovarian cancer tissues showed lower miR-203a-3p levels and higher ATM levels than adjacent normal tissues, both of which were associated with the FIGO stage, grade and prognosis of ovarian cancer. As confirmed by a dual-luciferase reporter gene assay, miR-203a-3p could target ATM. Furthermore, the miR-203a-3p mimic had multiple effects, including the inhibition of the proliferation, invasion and migration of A2780 and SKOV3 cells, the promotion of cell apoptosis, the arrest of the cell cycle at the G1 phase, and the blockage of the Akt/GSK-3ß/Snail signaling pathway. ATM siRNA had similar effects on the biological behaviors of ovarian cancer cells, and these effects could be reversed by a miR-203a-3p inhibitor. CONCLUSION: miR-203a-3p was capable of hindering proliferation, migration, and invasion and facilitating the apoptosis of ovarian cancer cells through its modulation of the Akt/GSK-3ß/Snail signaling pathway by targeting ATM, and therefore it could serve as a potential therapeutic option for ovarian cancer.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/genética , MicroRNAs/metabolismo , Neoplasias Ovarianas/fisiopatologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Adulto , Idoso , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Fosforilação , Prognóstico , Proteínas Proto-Oncogênicas c-akt/genética , RNA Interferente Pequeno , Fatores de Transcrição da Família Snail/genética
20.
J Sci Food Agric ; 94(11): 2295-300, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24395395

RESUMO

BACKGROUND: Clopidol is mainly used for the prevention and treatment of coccidiosis, which poses a serious potential hazard to public health, in veterinary medicine. The aim of this study was to prepare monoclonal antibodies (mAbs) against clopidol (CLOP) and develop an immunoassay for detecting CLOP residues in chicken tissues. After derivation, CLOP hapten was conjugated to carrier proteins to synthesize the artificial antigen, and immunized Balb/C mice were employed to screen mAbs. RESULTS: A sensitive hybridoma named C1G3 was screened out and two indirect competitive enzyme-linked immunosorbent assay (icELISA) standard curves were established. For the traditional two-step assay the linear range was from 0.06 to 98 ng mL(-1) , with half-maximal inhibitory concentration (IC50 ) and limit of detection (LOD) values of 2.76 ng mL(-1) and 0.03 ng mL(-1) respectively, while the rapid one-step icELISA had a working range from 0.08 to 102 ng mL(-1) , with IC50 and LOD values of 3.52 ng mL(-1) and 0.03 ng mL(-1) respectively. It was also indicated that a 10-fold dilution in chicken muscles gave an inhibition curve almost the same as that obtained in phosphate-buffered saline. When applied to spiking tests in chicken samples, the correlation coefficient (R(2) ) between concentrations added and measured was 0.9534. CONCLUSION: The results of this study suggest that the immunoassay described is a promising alternative for screening CLOP residues in biological matrices and is suitable for routine diagnostics.


Assuntos
Anticorpos Monoclonais , Clopidol/análise , Ensaio de Imunoadsorção Enzimática/normas , Contaminação de Alimentos/análise , Haptenos , Hibridomas , Carne/análise , Animais , Galinhas , Coccidiostáticos/análise , Dieta , Resíduos de Drogas/análise , Feminino , Haptenos/imunologia , Camundongos Endogâmicos BALB C , Músculos/química
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