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1.
Langmuir ; 37(35): 10461-10468, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34431681

RESUMO

A colloidal nanocrystal cluster (CNC) is a hierarchical nanostructure formed by clustering several nanocrystals into one nano-ensemble, which may exhibit unique optical or catalytic properties different from individual nanocrystals owing to the mutual interactions among neighboring component nanocrystals. However, there is still no universal synthetic route that could be applicable to diverse material compositions with precisely controlled hierarchical structures (i.e., nanocrystal number density, component nanocrystal size, and overall diameter of the CNC) up to now. Herein, a general and novel synthetic strategy was reported for crafting a wide range of inorganic CNCs (i.e., noble metal, semiconductor, and metal oxide) via utilizing amphiphilic star-like poly(4-vinylpyridine)-block-polystyrene diblock copolymers as nanoreactors prepared by sequential atom transfer radical polymerization. The hierarchical structure of rationally designed CNCs could be readily tailored by varying the P4VP molecular weight of star-like nanoreactors and the parameter optimization during the CNC preparation process, which was inaccessible by conventional synthetic methods.

2.
ACS Appl Mater Interfaces ; 13(33): 39806-39818, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34387459

RESUMO

Silver nanomaterials have attracted a great deal of interest due to their broad-spectrum antimicrobial activity. However, it is still challenging to balance the high antibacterial efficiency with low damage to biological cells of silver nanostructures, especially when the diameter decreases to less than 10 nm. Here, we developed a new type of Ag nanohybrid material via a unimolecular micelle template method, which presents amazing antibacterial activities and almost noncytotoxicity. First, water-soluble multiarm star-shaped brushlike copolymer α-CD-g-[(PEO40-g-PAA50)-b-PEO5]18 was precisely synthesized and its micelle behavior in different solvents was revealed. Then, nanocrystal clusters assembled by Ag grains (Ag@Template NCs) were prepared through an in situ redox route using the unimolecular micelle of α-CD-g-[(PEO40-g-PAA50)-b-PEO5]18 as the soft template, AgNO3 as a precursor, and tetrabutylammonium borohydride (TBAB) as the reducing agent. The overall size of the achieved Ag@Template NCs is controlled by the template structure at around 40 nm (Dh in DMF), and the size of the Ag grain can be easily regulated from ∼1 to ∼5 nm by adjusting the feeding ratio of AgNO3/acrylic acid (AA) units in the template from 1:10 to 1:1. Benefitting from the structural design of the template, all Ag@Template NCs prepared here exhibit excellent dispersibility and chemical stability in different aqueous environments (neutral, pH = 5.5, and 0.9% NaCl physiological saline solution), which play a crucial role in the long-term storage and potential application in a complex physiological environment. The antibacterial and cytotoxicity tests indicate that Ag@Template NCs display much better performance than Ag nanoparticles (Ag NPs), which have a comparable overall size of ∼25 nm. The inhibitory capability of Ag@Template NCs to bacteria strongly depends on the grain size. Specifically, the Ag@Template-1 NC assembled by the smallest grains (1.6 ± 0.3 nm) presents the best antibacterial activity. For E. coli (-), the MIC value is as low as 5 µg/mL (0.36 µg/mL of Ag), while for S. aureus (+), the value is around 10 µg/mL (0.72 µg/mL of Ag). The survival rate of L02 cells and lactate dehydrogenase assay together illustrate the low cytotoxicity possessed by the prepared Ag@Template NCs. Therefore, the proposed Ag@Template NC structure successfully resolves the high reactivity, instability, and fast oxidation issues of the ultrasmall Ag nanoparticles, and integrates high antibacterial efficiency and nontoxicity to biological cells into one platform, which implies its broad potential application in biomedicine.


Assuntos
Antibacterianos/efeitos adversos , Antibacterianos/química , Nanopartículas Metálicas/química , Prata/química , Antibacterianos/metabolismo , Boroidretos/química , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Polímeros/química , Compostos de Amônio Quaternário/química , Staphylococcus aureus/efeitos dos fármacos , Propriedades de Superfície , Nanomedicina Teranóstica
3.
Immun Inflamm Dis ; 9(3): 1000-1008, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34033704

RESUMO

OBJECTIVE: Previous studies have shown that increased neutrophils, as a manifestation of oxidative stress, may be involved in the progression of kidney disease. To our knowledge, little is known about the relationship between neutrophils and renal impairment in rheumatoid arthritis (RA). Therefore, we aim to investigate whether neutrophil is associated with renal impairment in RA patients. METHODS: We retrospectively investigated the renal function of 602 RA patients in the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine by estimated glomerular filtration rate (eGFR) from September 2018 and September 2019. The exposure variable was neutrophils, and the main outcome was eGFR. General data (gender, age, duration, hypertension, diabetes, hobbies, and medication history), whole blood markers, lipid indexes, and inflammatory indexes were collected as much as possible. We used multivariable logistic regression analysis to evaluate the association between neutrophils and renal impairment in RA participants. RESULTS: A total of 89 cases (14.8%) had renal impairment with eGFR < 60 ml/min/1.73 m2 , and 75 cases (84.3%) were female. Subgroup analysis showed that female (odds ratio [OR] = 0.523, 95% confidence interval [CI]: 0.318-0.867, p = .011), neutrophils greater thsn 7.5 × 109 /L (OR = 2.314, 95% CI: 1.310-4.087, p = .004), NLR > 3.53 (OR = 1.757, 95% CI: 1.104-2.799, p = .018), hemoglobin less than 120 g/L (OR = 2.413, 95% CI: 1.418-4.118, p = .001), and UA > 360 µmol/L (OR = 6.052, 95% CI: 3.708-9.878, p < .001) was related to renal damage in RA. Adjusted for several confounders, the multivariable analysis indicated that neutrophils greater than 7.5 × 109 /L (OR = 1.784, 95% CI: 1.164-3.288, p = .031) was independently associated with an increased risk of renal impairment in RA. CONCLUSION: Our study demonstrated that neutrophils greater than 7.5 × 109 /L was associated with a high risk of renal impairment in RA, suggesting that neutrophil may be a biomarker for renal impairment in RA.


Assuntos
Artrite Reumatoide , Neutrófilos , Estudos Transversais , Feminino , Taxa de Filtração Glomerular , Humanos , Estudos Retrospectivos
4.
J Colloid Interface Sci ; 600: 421-429, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34023703

RESUMO

Multi-stimuli responsive fluorescence probe could pave the way for monitoring more complex environmental changes. Here we prepared multifunctional nanoparticle Fe3O4@SiO2@P(DMAEMA-co-TPEE), which displayed yolk-shell morphology with well-defined polymer brush. With superparamagnetic Fe3O4 component and pH/temperature dual sensitive PDMAEMA polymer brush, the as prepared nanoparticles (YS-NPs) exhibited as multi-stimuli responsive fluorescence probe for real-time visual monitoring of environmental changes such as magnetic field, temperature and pH. Such YS-NPs could also be applied as a sensitive detector for CO2 in aqueous solution. Notably, the solution of YS-NPs showed high colloidal stability during the environmental changes, and surface aggregation-induced emission (S-AIE) was proposed for the aggregation of TPE residue on the surface of YS-NPs.


Assuntos
Nanocompostos , Nanopartículas , Polímeros , Temperatura
5.
J Phys Chem Lett ; 12(13): 3456-3463, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33792312

RESUMO

The past few years witnessed the rapid development of bottom-up synthesis strategies for preparing various nanostructures (i.e., nanoparticles, nanorods, nanowires, etc.) with distinct morphology-dependent properties. In this study, we reported a facile and efficient synthesis method for preparing anatase titanium dioxide (TiO2) nanorings based on multiarm, starlike amphiphilic polystyrene-b-poly(acrylic acid) (PS-b-PAA) diblock copolymers as nanoreactors which were prepared via a sequential atom-transfer radical polymerization (ATRP) technique followed by the conversion of polystyrene-b-poly(tert-butyl acrylate) (PS-b-PtBA) to PS-b-PAA. The outer PAA block of nanoreactors possessed carboxylic acid groups which could coordinate with a titanium precursor followed by high-temperature calcination to form crystalline TiO2 nanorings. The living nature of ATRP enabled the precise preparation of starlike diblock copolymer nanoreactors with a controlled length of each block (i.e., PtBA and PS), thereby tailoring the inner diameter and wall thickness of the resulting TiO2 nanorings, which were inaccessible to conventional routes.

6.
Front Med (Lausanne) ; 7: 610554, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33330573

RESUMO

Introduction: Patients with anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive amyopathic dermatomyositis (ADM) often develop rapidly progressive interstitial lung diseases (RP-ILD), with poor treatment success. Many studies have shown that this is the main cause of death in patients with anti-MDA5 antibody-positive ADM. Case Presentation: A 37-years-old woman developed a cough, shortness of breath, and a rash on both hands, which resembled Gottron's signs. Upon laboratory examination, the results were as follows: antinuclear antibody (ANA) positive; anti-Ro52 antibody positive; and anti-MDA5 antibody positive. Pulmonary high-resolution CT (HRCT) scan showed pulmonary interstitial inflammatory changes, and mediastinal and subcutaneous emphysema. She was finally diagnosed with anti-MDA5 antibody-positive ADM accompanied by RP-ILD. She was first given high-dose-steroid pulse therapy with methylprednisolone (500 mg per day for 3 days) followed by methylprednisolone (40 mg, daily), cyclosporine A (100 mg, twice per day), and hydroxychloroquine (200 mg, twice per day). Since her discharge from our hospital in March of 2018, she has maintained the methylprednisolone therapy (tapered to 10 mg daily), cyclosporine A (100 mg, twice per day), and hydroxychloroquine (200 mg, twice per day). Outcomes: Pulmonary HRCT scans taken on 4, 9, and 26 months after her discharge from our hospital showed that the interstitial pneumonitis had significantly improved and that mediastinal and subcutaneous emphysema had been gradually absorbed. The patient can now participate in regular work and activities of daily living. Conclusion: The treatment of methylprednisolone pulse therapy combined with cyclosporine A and hydroxychloroquine may be an option for the RP-ILD accompanied by anti-MDA-positive ADM. After the acute phase, this combination therapy strategy is helpful to the disease control of patients.

7.
Front Immunol ; 11: 556526, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117342

RESUMO

Leonurine, an active alkaloid extracted from Herba leonuri, is reported to have potent anti-inflammatory activity against rheumatoid arthritis (RA). However, the molecular mechanism of action of leonurine in RA remains poorly understood. In this study, we detected 3,425 mRNAs differentially expressed between CD4+ T cells of RA patients and those of healthy individuals using microarray raw data mining. Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that transcriptional coactivator with PDZ-binding motif (TAZ) regulates a variety of biological processes including T-helper (Th)-17 cell development, and was thus selected for functional verification. In a naïve CD4+ T cell differentiation assay, we found that TAZ overexpression was associated with impaired balance between T regulatory (Treg) and Th17 cells in vitro. TAZ overexpression increased the levels of the pro-inflammatory cytokines interleukin (IL)-17, IL-1ß, and tumor necrosis factor (TNF)-α and decreased that of the anti-inflammatory cytokine IL-10. Leonurine treatment had a direct recovery effect on the impaired balance and reduced the expression of TAZ and led to normalization of IL-17, IL-1ß, and TNF-α and IL-10. Furthermore, IL-6 was found to promote the expression of TAZ and receptor activator of nuclear factor kappa-B ligand (RANKL), and RANK. Leonurine significantly inhibited TAZ-mediated expression of RANKL, and RANK and IL-6 in synovial fibroblasts. We conclude that the therapeutic effect of leonurine was through suppression of TAZ led to restoration of Treg/Th17 balance and suppression of synovial fibroblast action.


Assuntos
Artrite Reumatoide/etiologia , Artrite Reumatoide/metabolismo , Ácido Gálico/análogos & derivados , Regulação da Expressão Gênica/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/metabolismo , Células Th17/efeitos dos fármacos , Células Th17/metabolismo , Fatores de Transcrição/genética , Artrite Reumatoide/patologia , Biomarcadores , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Ácido Gálico/farmacologia , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Imunofenotipagem , Linfócitos T Reguladores/imunologia , Células Th17/imunologia
8.
Med Sci Monit ; 26: e927104, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33112843

RESUMO

BACKGROUND The aim of this study was to evaluate the prevalence of inflammation and bone destruction of hand joints in rhupus patients through ultrasound examination. MATERIAL AND METHODS Ten rhupus patients and 33 systemic lupus erythematosus (SLE) patients with hand arthropathy were recruited in this single-center study, and the clinical features and ultrasound manifestations of these patients were analyzed. RESULTS We discovered that rhupus patients were older (47.31±4.35 years vs. 38.58±2.50 years, P=0.040), had longer duration of disease (median 72 months vs. median 12 months, P=0.040), had a higher positive rate (70% vs. 10.71%, P<0.001), and had higher titers of anti-CCP antibody (42.633±14.520 vs. 2.121±0.970, P<0.001) than SLE patients with arthropathy. More importantly, the prevalence rates of synovial hyperplasia (90% vs. 42.42%, P=0.008), synovitis (90% vs. 18.18%, P<0.001), synovial hyperplasia (70% vs. 10.71%, P<0.001), and bone destruction (70% vs. 6.06%, P<0.001) were higher in rhupus patients than in SLE patients with arthropathy. CONCLUSIONS Rhupus patients are more prone to develop synovitis, synovial hyperplasia, and bone destruction. Therefore, more attention should be paid to protection of the joints in rhupus patients.


Assuntos
Artrite Reumatoide/diagnóstico por imagem , Articulação da Mão/diagnóstico por imagem , Inflamação/diagnóstico por imagem , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Articulação do Punho/diagnóstico por imagem , Adulto , Artrite Reumatoide/patologia , Feminino , Articulação da Mão/patologia , Humanos , Inflamação/patologia , Lúpus Eritematoso Sistêmico/patologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Ultrassonografia Doppler , Articulação do Punho/patologia
9.
Med Sci Monit ; 26: e925593, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32991572

RESUMO

BACKGROUND To use a gout-specific quality of life (QoL) tool, the Gout Impact Scale (GIS), to evaluate characteristics of gout affecting QoL in subjects with gout. MATERIAL AND METHODS In this cross-sectional study, 169 individuals with gout completed the 24-item GIS and a general questionnaire regarding gout characteristics. The reliability and validity of the GIS were verified by Cronbach's a and exploratory factor analysis, respectively. The impact of gout characteristics on the QoL of subjects with gout was assessed by stepwise multiple regression analysis. RESULTS The 169 subjects with gout included 149 (88.2%) men and 20 (11.8%) women, of median age 43 years. The reliability of the GIS was appropriate (0.84-0.90), except for Gout Medication Side Effects (0.69) and Unmet Gout Treatment Need (0.59). Exploratory factor analysis showed that construct validity was acceptable, with a cumulative variance contribution rate of 5 common factors of 70.09% and factor loading >0.5 between each pair of items of the GIS. Univariate analysis showed that male sex was positively correlated with Well-being During Attack (p<0.05), and that source of medical expenses, current cigarette use and drinking were significantly correlated with Unmet Gout Treatment Need (p<0.05 each). A family history of gout, gout flares, and attack frequency were significantly correlated with total GIS, Well-being During Attack, and Gout Concern during Attack (p<0.05 each). Multivariate analysis suggested that history of gouty arthritis, acute attack and attack frequency had a considerable impact on QoL (p<0.05 each). CONCLUSIONS The GIS showed acceptable reliability and validity in identifying associations between poor QoL and gout characteristics.


Assuntos
Grupo com Ancestrais do Continente Asiático , Gota , Qualidade de Vida , Inquéritos e Questionários , Adulto , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
ACS Appl Mater Interfaces ; 12(37): 42161-42168, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32840349

RESUMO

Silicon quantum dots (SiQDs) are explored for the first time as an efficient photocatalyst for visible-light-regulated reversible addition-fragmentation chain transfer (RAFT) polymerization. The fluorescence quenching confirmed the photoinduced electron transfer (PET) between SiQDs and RAFT reagents. Besides all features of controlled radical polymerization, the SiQDs catalyzed PET-RAFT polymerization also exhibit good temporal control, high chain-end fidelity, and versatility with diverse monomers. Moreover, amino-functionalized SiQDs can be easily coated on the surface of substrates (silicon wafer) owing to the electrostatic interaction, and play a dual role of polymer-substrate connector and photocatalyst for the surface-initiated PET-RAFT polymerization. The SiQD-coated wafer was also proved to be an efficient recycle photocatalyst for PET-RAFT polymerization.

11.
Langmuir ; 36(24): 6690-6697, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32493013

RESUMO

We reported the synthesis of a well-defined hollow polymer nanoparticle derived from star-shaped unimolecular micelles. ß-Cyclodextrin was first applied as an efficient macroinitiator to prepare a star-shaped PCL via ring-opening polymerization (ROP). Then, the star-shaped PCL was modified to be a macro-RAFT agent for photoinduced electron/energy transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization of S-Cl monomers. The prepared unimolecular micelles can be photocross-linked under UV irradiation after a simple nucleophilic substitution reaction, which made -Cl groups to be -N3 groups. After the selective removal of the PCL core, hollow polymer nanoparticles were achieved and exhibited to be a general nanoreactor strategy for the fabrication of nanocrystals with well-controlled architectures. Compared with unimolecular micelle templates, the nanocrystals prepared by hollow templates are absolutely pure as no polymer chains are embedded in the inorganic nanocrystals. In addition, by changing the concentration of the precursor, the structure of the nanocrystal can be changed from a normal spherical structure to a hollow structure.

12.
Chem Asian J ; 15(7): 1014-1017, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32012458

RESUMO

Aggregation-induced emission (AIE) technology has been demonstrated to be a facile approach for in-situ monitoring atom transfer radical polymerization (ATRP). A series of tertraphenyl ethylene (TPE)-containing α-bromo compounds were synthesized and applied as ATRP initiators. The photoluminescent (PL) emission of the polymerization system is proved to be sensitive to the local viscosity owing to the AIE characteristics of TPE. Linear relationships between the resulting molecular weight Mn and PL intensity were observed in several polymerization systems with different monomers, indicating the variability of this technique. Compared to physical blending, the chemical bonding of the TPE group in the chain end has higher sensitivity and accuracy to the polymer segments and the surrounding environment. This work promoted the combination of the AIE technique and controlled living radical polymerization, and introduced such an optical research platform to the ATRP polymerization process.

13.
Sci Rep ; 9(1): 1869, 2019 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-30755621

RESUMO

An unconventional but facile approach to prepare size-tunable core/shell ferroelectric/polymeric nanoparticles with uniform distribution is achieved by metal-free atom transfer radical polymerization (ATRP) driven by visible light under ambient temperature based on novel hyperbranched aromatic polyamides (HBPA) as a functional matrix. Cubic BaTiO3/HBPA nanocomposites can be prepared by in-situ polycondensation process with precursors (barium hydroxide (Ba(OH)2) and titanium(IV) tetraisopropoxide (TTIP)) of ferroelectric BaTiO3 nanocrystals, because precursors can be selectively loaded into the domain containing the benzimidazole rings. At 1200 °C, the aromatic polyamide coating of cubic BaTiO3 nanoparticles are carbonized to form carbon layer in the inert environment, which prevents regular nanoparticles from gathering. In addition, cubic BaTiO3 nanoparticles are simultaneously transformed into tetragonal BaTiO3 nanocrystals after high temperature calcination (1200 °C). The outer carbon shell of tetragonal BaTiO3 nanoparticles is removed via 500 °C calcination in air. Bi-functional ligand can modify the surface of tetragonal BaTiO3 nanoparticles. PMMA polymeric chains are growing from the initiating sites of ferroelectric BaTiO3 nanocrystal surface via the metal-free ATRP technique to obtain core/shell ferroelectric BaTiO3/PMMA hybrid nanoparticles. Changing the molar ratio between benzimidazole ring units and precursors can tune the size of ferroelectric BaTiO3 nanoparticles in the process of polycondensation, and the thickness of polymeric shell can be tailored by changing the white LED irradiation time in the organocatalyzed ATRP process. The dielectric properties of core/shell BaTiO3/PMMA hybrid nanoparticles can be also tuned by adjusting the dimension of BaTiO3 core and the molecular weight of PMMA shell.

14.
Artigo em Inglês | MEDLINE | ID: mdl-30596330

RESUMO

The modification of semiconductor nanostructures with metallic nanocomponents can promote the separation of electron/hole from photoexited semiconductors by forming heterojunctions, thus exhibit enhanced photocatalytic activities and potential applications. In this study, Pt-based NPs, including Pt, PtCu, and PtCuCo are employed as model co-catalysts to comparatively study their capability to enhance the photocatalytic activity of TiO2 nanosheets. It was found that each of Pt, PtCu, and PtCuCo can greatly enhance the photocatalytic activity of TiO2 toward degradation of organic dyes. Using electron spin resonance spectroscopy, we demonstrated that deposition of Pt-based NPs resulted in more production of reactive oxygen species including hydroxyl radicals, superoxide, and singlet oxygen. The enhancing effects of Pt-based NPs on generation of ROS and photocatalytic activity showed same trend: PtCuCo > PtCu > Pt. The mechanism underlying the enhancement differences in Pt-based NPs may be mainly related to electronic structure change of Pt in alloying with Cu and Co. These results are valuable for designing hybrid nanomaterials with high photocatalytic efficiency for applications in water purification and antibacterial products.


Assuntos
Cobalto/química , Corantes/análise , Cobre/química , Nanopartículas Metálicas/química , Platina/química , Espécies Reativas de Oxigênio/análise , Poluentes Químicos da Água/análise , Catálise , Fotólise , Semicondutores , Titânio/química
15.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1081-1082: 15-24, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29499464

RESUMO

Three alkylated DNA adducts, N3­methyladenine, N3­ethyladenine and N7­ethylguanine, have been proved to be potential biomarkers for DNA injury caused by exposure to cigarette smoke. In this study, a highly specific and sensitive method using a new mixed-mode sulfonate-functionalized poly(glycidyl methacrylate-divinylbenzene) as a solid-phase extraction sorbent was developed for the analysis of these three alkylated-purine adducts in human urine. Under optimized conditions, the prepared sorbent interacts strongly with these urinary adducts, demonstrating high clean-up efficiency and extraction recovery. The method detection limits (S/N ≥ 3) of N3-MeA, N3-EtA and N7-EtG were 1.75, 0.20, and 0.15 pg mL-1, respectively, while the method quantitation limits were found to be 5.78, 0.66, and 0.49 pg mL-1 for N3-MeA, N3-EtA and N7-EtG, respectively. The intra-day and inter-day precisions were investigated, of which were in the range of 1.6-3.8% and 3.2-5.6%, respectively. The recovery values of the alkylated DNA adducts in spiked urine sample were ranged 89.7-104.5%. Their concentrations were statistically significantly higher in smokers than in nonsmokers. These results show that the proposed method is suitable for the analysis of alkylated DNA adducts.


Assuntos
Cromatografia Líquida/métodos , Adutos de DNA/urina , Microesferas , Purinas/urina , Espectrometria de Massas em Tandem/métodos , Adulto , Alquilação , Biomarcadores , Adutos de DNA/química , Adutos de DNA/isolamento & purificação , Compostos de Epóxi/química , Humanos , Modelos Lineares , Masculino , Metacrilatos/química , Purinas/química , Purinas/isolamento & purificação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fumar , Extração em Fase Sólida/métodos , Ácidos Sulfônicos/química , Compostos de Vinila/química , Adulto Jovem
16.
Int Immunopharmacol ; 55: 174-182, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29268189

RESUMO

In rheumatoid arthritis (RA), fibroblast-like synoviocytes (FLSs) play an essential role in cartilage destruction. Aggressive migration and invasion by FLSs significantly affect RA pathology. Kaempferol has been shown to inhibit cancer cell migration and invasion. However, the effects of kaempferol on RA FLSs have not been investigated. Our study aimed to determine the effects of kaempferol on RA both in vitro and in vivo. In vitro, cell migration and invasion were measured using scratch assays and the Boyden chamber method, respectively. The cytoskeletal reorganization of RA FLSs was evaluated by immunofluorescence staining. Matrix metalloproteinase (MMP) levels were measured by real-time PCR, and protein expression levels were measured by western blotting. In vivo, the effects of kaempferol were evaluated in mice with CIA. The results showed that kaempferol reduced migration, invasion and MMP expression in RA FLSs. In addition, we demonstrated that kaempferol inhibited reorganization of the actin cytoskeleton during cell migration. Moreover, kaempferol dramatically suppressed tumor necrosis factor (TNF)-α-induced MAPK activation without affecting the expression of TNF-α receptors. We also demonstrated that kaempferol attenuated the severity of arthritis in mice with CIA. Taken together, these results suggested that kaempferol inhibits the migration and invasion of FLSs in RA by blocking MAPK pathway activation without affecting the expression of TNF-α receptors.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Fibroblastos/fisiologia , Quempferóis/uso terapêutico , Sinoviócitos/fisiologia , Actinas/metabolismo , Adulto , Idoso , Animais , Artrite Experimental , Movimento Celular , Células Cultivadas , Citoesqueleto/metabolismo , Feminino , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Endogâmicos DBA , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/metabolismo
17.
ACS Omega ; 3(2): 2463-2469, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-31458541

RESUMO

In this work, we have explored a simple and facile approach to prepare optically active helical polyamides. The hydroxyl groups of l-TA and d-TA were protected by O-alkoyl ester, and the resulting enantiomers, l-2,3-di-O-acetyl-tartaric acid (l-ATA) and d-2,3-di-O-acetyl-tartaric acid (d-ATA) crystals, were obtained. A pair of aliphatic homochiral polyamides of PA-l and PA-d are prepared using l-ATA, d-ATA, and achiral 1,11-undecanediamine as building blocks via interfacial polycondensation. PA-l and PA-d display negative and positive mirror circular dichroism (CD) spectra images in both solution and solid state. Moreover, the polyamides in solid state display different CD signals and stronger optical activity compared to those in ethanol and even the related chiral monomers in solid state, which was due to the helical conformation of the polyamides in solid state. Scanning electron microscopy results indicated that the aggregations of PA-l express left-handed helical sense, whereas those of PA-d express right-handed helix. In addition, the induced CD signals from the chiral conformation of the backbone become weaker when increasing the temperature from 0 to 60 °C in dilute solution. Either of the polyamides displays relatively stable CD images in solid state when elevating the temperature from 0 to 90 °C.

18.
Rheumatology (Oxford) ; 56(8): 1417-1427, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28431044

RESUMO

Objective: To explore the role of leonurine in the regulation of synovial inflammation and joint destruction inRA. Methods: Fibroblast-like synoviocytes were isolated from synovial tissue from RA patients. Pro-inflammatory cytokine and MMP expression was evaluated using real-time PCR and a cytometric bead array. Cell migration and invasion in vitro were measured using the Boyden chamber method and the scratch assay, respectively. Protein expression was measured by western blotting. Nuclear factor kappa B (NF-κB) nuclear translocation was detected by immunofluorescence. The in vivo effect of leonurine was evaluated in mice with CIA. Results: Leonurine treatment significantly decreased the production of pro-inflammatory cytokines (IL-1ß, IL-6, IL-8 and TNFα) and MMPs (MMP-1 and MMP-3) and suppressed the migration and invasion of RA fibroblast-like synoviocytes. The molecular analysis revealed that leonurine impaired TNFα-induced NF-κB signalling by inhibiting the phosphorylation and degradation of inhibitor of NF-κB alpha (IκBα) and subsequently preventing the nuclear translocation of the NF-κB p65 subunit. Leonurine also inhibited the p38 and Jun N-terminal kinase mitogen-activated protein kinases signalling pathways without affecting ERK signalling. Intraperitoneal injection of leonurine reduced synovial inflammation, joint destruction and the serum IL-1ß, IL-6 and TNFα levels in mice with CIA. Conclusion: Our findings show that leonurine reduces synovial inflammation and joint destruction in RA through the NF-κB and mitogen-activated protein kinases pathways. Leonurine has potential as a therapeutic agent for RA.


Assuntos
Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Ácido Gálico/análogos & derivados , Adulto , Animais , Artrite Experimental/induzido quimicamente , Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Citocinas/efeitos dos fármacos , Feminino , Fibroblastos/metabolismo , Ácido Gálico/farmacocinética , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Metaloproteinase 1 da Matriz/efeitos dos fármacos , Metaloproteinase 3 da Matriz/efeitos dos fármacos , Camundongos , Pessoa de Meia-Idade , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Membrana Sinovial/efeitos dos fármacos , Sinoviócitos/efeitos dos fármacos , Sinoviócitos/patologia , Fator de Transcrição RelA/efeitos dos fármacos
19.
Artigo em Inglês | MEDLINE | ID: mdl-28157663

RESUMO

2-Amino-9H-pyrido[2,3-b]indole (AαC), which has been reported to be 40-258ng per cigarette, was regarded as a probable human carcinogen (Group 2B) and harmful composition in Hoffman list. Thus, it is of great significance to develop an effective method for the accurate identification of AαC and its metabolites. In the present study, we have investigated for the first time the in vivo and in vitro metabolites of AαC using ultra performance liquid chromatography combined with diode array detector and time-of-flight mass spectrometry (UPLC-DAD and UPLC-Q-TOF-MS/MS). A comparative study showed that the metabolic patterns of AαC in beagle, mouse, rat and human liver microsomes were of significant difference with these in rat urine. For the metabolism of AαC in liver microsomes, nine metabolites of AαC, including five hydroxy metabolites, two quinone metabolites and two N-dimer metabolites, have been found. However, metabolism of AαC in rats is a phase II process with complex enzyme catalysis, 23 metabolites including C- and N-oxidation, O- and N-glycosylation, O- and N-sulfonation, and N-acetylation were identified in rat urine. In addition, five new N-acetyl-AαC-OH metabolites were identified for the first time, indicating a possible new pathway for the metabolism. This study significantly enriched our knowledge about the metabolism of AαC, and will be useful for a better understanding of its harmfulness and toxicity.


Assuntos
Carbolinas/química , Carbolinas/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Microssomos Hepáticos/metabolismo , Espectrometria de Massas em Tandem/métodos , Animais , Carbolinas/análise , Carbolinas/farmacocinética , Feminino , Masculino , Redes e Vias Metabólicas , Ratos
20.
ACS Omega ; 2(8): 4080-4087, 2017 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31457709

RESUMO

A series of optically active polyamides, PAnLATs (n = 9-12), were prepared by polycondensation of l-tartrate-derived diacid with achiral aliphatic diamines in which the number of the methylene is from 9 to 12. The monomers could be obtained easily, and the synthesis of the polyamides is facile. The number-average molecular weight (M̅ n) of PA9LAT, PA10LAT, PA11LAT, and PA12LAT is 35 500, 24 400, 35 800, and 20 900 g/mol, respectively, and the related polydispersity index is 3.4, 3.3, 3.4, and 3.0. These polyamides display intense optical activity in solution. Particularly, the stronger ellipticities and different circular dichroism (CD) images were presented when the polymers were evaluated in the solid state. The crystalline properties of the polymers were studied to illuminate the enhanced aggregation-induced CD. Moreover, PA9LAT and PA11LAT have similar crystal parameters, and PA10LAT is similar to PA12LAT, which revealed why the chirality of the polyamides displays an odd-even effect. On the other hand, the solubility of the polymers in organic solvents was studied, and thermogravimetric-differential thermal analyzer was utilized to characterize the thermal properties.

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