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1.
Biochem Cell Biol ; 101(3): 235-245, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36786377

RESUMO

In the process of orthodontic tooth movement (OTM), periodontal ligament fibroblasts (PDLFs) must undergo osteogenic differentiation. OTM increased the expression of Zinc finger and BTB domain-containing 16 (ZBTB16), which is implicated in osteogenic differentiation. Our goal was to investigate the mechanism of PDLF osteogenic differentiation mediated by ZBTB16. The OTM rat model was established, and PDLFs were isolated and exposed to mechanical force. Hematoxylin-eosin staining, Alizarin Red staining, immunofluorescence, and immunohistochemistry were carried out. The alkaline phosphatase (ALP) activity was measured. Dual-luciferase reporter gene assay and chromatin immunoprecipitation assay were conducted. In OTM models, ZBTB16 was significantly expressed. Additionally, there was an uneven distribution of PDLFs in the OTM group, as well as an increase in fibroblasts and inflammatory infiltration. ZBTB16 interference hindered PDLF osteogenic differentiation and decreased Wnt and ß-catenin levels. Meanwhile, ZBTB16 activated the Wnt/ß-catenin pathway. ZBTB16 also enhanced the expression of the osteogenic molecules osterix, osteocalcin (OCN), osteopontin (OPN), and bone sialo protein (BSP) at mRNA and protein levels. The interactions between Wnt1 and ZBTB16, as well as GCN5 and ZBTB16, were also verified. The adeno-associated virus-shZBTB16 injection also proved to inhibit osteogenic differentiation and reduce tooth movement distance in in vivo tests. ZBTB16 was up-regulated in OTM. Through acetylation modification of ZBTB16, GCN5 regulated the Wnt/ß-catenin signaling pathway and further mediated PDLF osteogenic differentiation.


Assuntos
Osteogênese , beta Catenina , Ratos , Animais , Osteogênese/genética , beta Catenina/metabolismo , Acetilação , Técnicas de Movimentação Dentária , Ligamento Periodontal , Via de Sinalização Wnt/genética , Diferenciação Celular , Células Cultivadas , Proteína com Dedos de Zinco da Leucemia Promielocítica/metabolismo , Histona Acetiltransferases/metabolismo
2.
Int J Mol Sci ; 23(4)2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35216158

RESUMO

Organic photovoltaics (OPVs) differ from their inorganic counterparts because of inevitable electronic disorders and structural heterogeneity. Charge carrier traps are inevitable in organic semiconductors. A common failure mechanism of OPVs is the development of an S-shaped current density-voltage characteristic (J-V curve). Herein, we focus on investigating the underlying physical mechanism of S-shaped deformation of J-V curve of the inverted organic photovoltaic devices with bulk-heterojunction, proven by experiments with the n-doped electron extraction layer and numerical simulations assuming electron traps (0.1 eV deeper) in the electron extraction layer. The numerical simulations are quite consistent with the experimental results. In addition, the open circuit voltage induced by S-kink is exemplified to be enhanced after removing the electron traps in the interlayer by introducing a dopant of cesium carbonate.


Assuntos
Condutividade Elétrica , Técnicas Eletroquímicas/métodos , Elétrons , Fótons , Benzotiazóis/química , Carbonatos/química , Césio/química , Simulação por Computador , Técnicas Eletroquímicas/instrumentação , Polímeros/química
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(6): 1074-1080, 2022 Nov.
Artigo em Zh | MEDLINE | ID: mdl-36443055

RESUMO

Objective: To analyze the epidemiological characteristics of hand, foot, and mouth disease (HFMD) in Chengdu from 2012 to 2020, to make comparison in order to examine the changes in incidence before and after vaccination was introduced, and to provide basis for the prevention of HFMD in the future. Methods: Descriptive epidemiological methods were adopted to analyze the incidence, mortality and rate of severe cases of HFMD cases reported in Chengdu from 2012 to 2020. Results: From 2012 to 2020, the cumulative cases of HFMD reported in Chengdu were as many as 279216, of which, there were 2201 severe cases and 16 deaths. The incidence increased every other year, reaching 326.43 per 100000 person-years, the highest ever, in 2018. The rate of severe cases and mortality had shown a decreasing trend since 2016. A total of 11892 cases of EV71, CoxA16 and other enteroviruses were detected in the laboratory, accounting for 14.8%, 18.8% and 66.3%, respectively. Since 2016, HFMD cases caused by EV71 virus infection had shown an overall decreasing trend, cases caused by Cox A16 virus infection had increased every other year, and cases caused by other enteroviral infections had shown an overall increasing trend. The reported cases were mainly concentrated in children aged 0-5 years (92.1%), with those in the age group of 1-2 years reporting the highest number of cases. For children of different ages, male patients always outnumber female patients. The geographic distribution showed that the areas with high HFMD incidence were always located in the central part of Chengdu City, and the three districts with the highest incidence growth rate were Qingbaijiang District, Shuangliu District, and Longquanyi District. Temporal distribution of HFMD cases showed an obvious bimodal distribution, with most of the cases concentrated in May through August and October through December of each year. The number of new cases reached the highest (12309 cases) in July 2018. Conclusion: While continuing to promote EV71 vaccination in the future, Chengdu also needs to pay more attention to viral infection serotypes other than EV71 and Cox A16 and conduct research on multivalent vaccines against a variety of enteroviruses. The focus of prevention and control can be placed on areas with high population density, large floating populations, large numbers of agriculture-related communities, and insufficient individual awareness of hygiene. For the second circle of Chengdu city, the disinfection of agriculture-related communities should be strengthened, and information sessions or other health education activities could be organized for individuals and daycare facilities with low awareness of the importance of hygiene. In addition, more attention should be given to the prevention and control of HFMD in the high incidence seasons.


Assuntos
Infecções por Enterovirus , Doença de Mão, Pé e Boca , Criança , Humanos , Feminino , Masculino , Lactente , Pré-Escolar , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/prevenção & controle , Vacinação , Antígenos Virais
4.
Mikrochim Acta ; 185(4): 231, 2018 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-29594735

RESUMO

The authors describe an environmentally friendly and fast (~14 min) method for the synthesis of homogeneously distributed fluorescent polydopamine nanodots (PDA-NDs) using KMnO4 as the oxidant. Alkaline phosphatase (ALP) catalyzes the hydrolysis of ascorbic acid 2-phosphate to release free ascorbic acid which undergoes an in-situ redox reaction with KMnO4. Depending on the activity of ALP, more or less KMnO4 is consumed, and this affects the formation of the PDA-NDs. Based on this finding, a sensitive method was worked out to quantify the activity of ALP via real-time formation of fluorescent PDA-NDs. The fluorometric signal (best measured at excitation/emission peaks of 390/500 nm) is linear in the 1 to 50 mU·mL-1 ALP activity range, and the limit of the detection is as low as 0.94 mU·mL-1 (based on 3 σ/m). The method was successfully applied to the determination of ALP activity in spiked human serum and in MCF-7 cell lysates. It was also applied in a method to screen for inhibitors of ALP. Graphical abstract Schematic of a fluorometric method for the determination of alkaline phosphatase (ALP) activity. The method is based on the in-situ regulation of the formation of fluorescent polydopamine nanodots (PDA-NDs) through the competition between the KMnO4-induced polymerization of dopamine and ALP-directed ascorbic acid 2-phosphate (Asc-2P) hydrolysis. AA: Ascorbic acid.


Assuntos
Fosfatase Alcalina/metabolismo , Ensaios Enzimáticos/métodos , Fluorometria/métodos , Indóis/química , Nanopartículas/química , Polímeros/química , Fosfatase Alcalina/antagonistas & inibidores , Animais , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/farmacologia , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Humanos , Limite de Detecção , Células MCF-7 , Oxirredução
5.
J Inflamm Res ; 16: 5601-5612, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38046402

RESUMO

Objective: Oxidative stress is involved in the mechanisms associated with temporomandibular joint (TMJ) diseases. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a crucial oxidative stress marker, but the specific mechanisms of its regulation in the early stages of mandibular condylar cartilage (MCC) degeneration remain unclear. This study aimed to explore the regulatory role of Nrf2 and its related oxidative stress signaling pathway in the early stage of MCC degeneration. Materials and Methods: Overloading force-induced MCC degeneration was performed in wild-type and Nrf2 knockout mice, as well as in mice after treatment with the Nrf2 activator cardamonin. Changes in MCC degeneration and the expression of oxidative stress markers in the corresponding situations were observed. Results: Nrf2 and NADPH oxidase 2 (NOX2) expression were elevated during early MCC degeneration induced by an overloading force. MCC degeneration was aggravated when Nrf2 was knocked out, accompanied by increased NOX2 and superoxide dismutase 2 (SOD2) expression. The MCC degeneration process was alleviated after cardamonin treatment, with activation of the Nrf2 pathway and decreased NOX2 and SOD2 expression. Conclusion: Early MCC degeneration is accompanied by mild oxidative stress progression. Activated Nrf2 and related pathways could alleviate the degeneration of MCC.

6.
Nanoscale ; 15(8): 3940-3951, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36723206

RESUMO

Hydroxyapatite (HA) is a biomimetic biomaterial that has been widely used in bone repair for many years. However, the increased risk of infection after surgery and long-time tracing for the material distribution and degradation during bone reconstruction remain challenges in the clinic. Zinc (Zn) is considered as an indispensable microelement for humans and is characterized with antibacterial action and osteogenic activity. Terbium (Tb), a rare-earth element, emits stable fluorescence under ultraviolet light. Here, Tb3+/Zn2+ co-doped hydroxyapatite (HA:Tb/Zn) was prepared to synchronously realize the antibacterial effect, osteogenic activity, and long-time tracing property. We found that HA:Tb/Zn had a strong antibacterial effect on both Gram-positive and Gram-negative clinical infectious bacteria, as well as improved osteogenic activity. HA:Tb/Zn also displayed stable green fluorescence in vitro and in vivo, which indicated great potential for recognizing the material changes during the bone reconstruction process. The combination of the ternary functions is of great significance to control the overuse of antibiotics and realize long-time tracing, and provide a versatile design on biomaterials in bone repair.


Assuntos
Durapatita , Térbio , Humanos , Materiais Biocompatíveis , Zinco , Antibacterianos
7.
Front Bioeng Biotechnol ; 10: 1098015, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36714614

RESUMO

Background: Periodontitis is a prevalent disease caused teeth lost. The present rat models inducing periodontitis with thread ligature and metal steel ligature have some disadvantages. Methods: We modified the existing rat ligature periodontitis model by fixing the thread ligature on the metal steel ligature passed through the gap between the first and second molars of rats with detailed modeling steps and illustrations. We research the pathological process of the periodontitis induced by the modified model, and briefly compared the modified model with the thread ligature model and the metal steel ligature model. Result: Our experimental results showed that there was an aggravation in inflammatory infiltration and alveolar bone resorption in modeling area within 14 days of initial induction. After that, the inflammatory infiltration was reduced. And no significant increase in alveolar bone destruction appeared. The modified model was more reliable compared to the thread ligature model, and had greater ability of bacterial aggregation compared to the metal steel ligature model. Conclusion: The modified method covered pathological process of the periodontitis, and showed sufficient efficiency and reliability in inducing rat periodontitis.

8.
Commun Biol ; 5(1): 1125, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36284165

RESUMO

Populus wilsonii is an important species of section Leucoides, and the natural populations mainly grow in southwest China. In this study, a single genotype of wild P. wilsonii was sequenced and assembled at genome size of 477.35 Mb in 19 chromosomes with contig N50 of 16.3 Mb. A total of 38,054 genes were annotated, and 49.95% of the genome was annotated as repetitive elements. Phylogenetic analysis identified that the divergence between P. wilsonii and the ancestor of P. deltoides and P. trichocarpa was 12 (3-23) Mya. 4DTv and Ks distributions supported the occurrence of the salicoid WGD event (~65 Mya). The highly conserved collinearity supports the close evolutionary relationship among these species. Some key enzyme-encoding gene families related to the biosynthesis of lignin and flavonoids were expanded and highly expressed in the stems or leaves, which probably resist the damage of the natural environment. In addition, some key gene families related to cellulose biosynthesis were highly expressed in stems, accounting for the high cellulose content of P. wilsonii variety. Our findings provided deep insights into the genetic evolution of P. wilsonii and will contribute to further biological research and breeding as well as for other poplars in Salicaceae.


Assuntos
Populus , Populus/genética , Filogenia , Lignina , Melhoramento Vegetal , Cromossomos , Flavonoides
9.
Environ Sci Pollut Res Int ; 29(49): 74118-74132, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35633460

RESUMO

Soil acidification is a problem widely occurring worldwide, which severely threaten food security and agricultural sustainability. Calcium lignosulfonate (CaLS), a cheap and ecofriendly compound, is used for the first time to amend acid soil by utilizing its unique organic and inorganic functional moieties simultaneously. Both column leaching and incubation experiments were conducted to investigate the comparative effects of CaLS (four rates at 5, 10, 15, 20 g kg-1) and compared with conventional amendments, including gypsum (5 g kg-1), lignin (5 g kg-1), L + G (each at 5 g kg-1), and control. The soil pH, exchangeable acidity and base cations, organic carbon, and different Al fractions were determined to unravel the ameliorative performance and mechanism of the treatments. Regardless of application modes and dosages, the results demonstrated that CaLS incorporation significantly increased soil pH, exchangeable Ca2+, cation exchange capacity, and organic carbon and decreased the contents of exchangeable acidity, especially exchangeable Al3+. The ameliorative mechanism was that amendment material led to the displacement of H+ and Al3+ off soil colloids by Ca2+. These released H+ and Al3+ which complexed with lignosulfonate anions into soluble organo-Al were all quickly leached from the soil column. The CaLS addition enhanced the transformation of exchangeable Al3+ and low-to-medium organo-Al complexes into highly stable organically bound fractions and immobilized into the soil. The complexing of CaLS functional groups with Al3+ impeded Al3+ from undergoing hydrolysis to produce more H+. As an environmental-friendly material, CaLS can be a promising amendment for soil acidity and Al toxicity amelioration.


Assuntos
Poluentes do Solo , Solo , Ácidos , Sulfato de Cálcio , Carbono , Cátions , Concentração de Íons de Hidrogênio , Lignina/análogos & derivados , Compostos Orgânicos , Solo/química , Poluentes do Solo/análise
10.
J Biomed Nanotechnol ; 17(6): 1007-1019, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34167616

RESUMO

In recent years, the emergence of non-toxic but catalytically active inorganic nanoparticles has attracted great attention for cancer treatment, but the therapeutic effect has been affected by the limited reactive oxygen species in tumors. Therefore, the combination of chemotherapy and chemodynamic therapy is regarded as a promising therapeutic strategy. In this paper, we reported the preparation and bioactivity evaluation of poly(lactic acid-co-glycolic acid) (PLGA) grafted-γ-Fe2O3 nanoparticles with dual response of endogenous peroxidase and catalase like activities. Our hypothesis is that PLGAgrafted γ-Fe2O3 nanoparticles could be used as a drug delivery system for the anti-tumor drug doxorubicin to inhibit the growth of lung adenocarcinoma A549 cells; meanwhile, based on its mimic enzyme properties, this kind of nanoparticles could be combined with doxorubicin in the treatment of A549 cells. Our experimental results showed that the PLGAgrafted γ-Fe2O3 nanoparticles could simulate the activity of catalase and decompose hydrogen peroxide into H2O and oxygen in neutral tumor microenvironment, thus reducing the oxidative damage caused by hydrogenperoxide to lung adenocarcinoma A549 cells. In acidic microenvironment, PLGA grafted γ-Fe2O3 nanoparticles could simulate the activity of peroxidase and effectively catalyze the decomposition of hydrogen peroxide to generate highly toxic hydroxyl radicals, which could cause the death of A549 cells. Furthermore, the synergistic effect of peroxidase-like activity of PLGA-grafted γ-Fe2O3 nanoparticles and doxorubicin could accelerate the apoptosisand destruction of A549 cells, thus enhancing the antitumor effect of doxorubicin-loaded PLGA-grafted γ-Fe2O3 nanoparticles. Therefore, this study provides an effective nanoplatform based on dual inorganic biomimetic nanozymes for the treatment of lung cancer.


Assuntos
Adenocarcinoma de Pulmão , Nanopartículas , Células A549 , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Compostos Férricos , Humanos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Microambiente Tumoral
11.
Exp Neurol ; 326: 113176, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31926167

RESUMO

Epidemiological studies suggest that chronic periodontitis (CP) is closely associated with the incidence and progression of cognitive impairment. The present study investigated the causal relationship between CP and cognitive decline and the underlying mechanism in mice. Long-term ligature around the left second maxillary molar tooth was used to induce CP in mice. Severe alveolar bone loss and inflammatory changes were observed in gingival tissues, accompanied by progressive cognitive deficits during a 12-month period. We also observed cerebral neuronal and synaptic injury and glial activation in this mouse model of CP. Furthermore, CP mice exhibited significant dysbiosis of the oral and gut microbiota, disruption of the intestinal barrier and blood-brain barrier, increases in the serum contents of proinflammatory cytokines and lipopolysaccharide (LPS), and increases in brain LPS levels, Toll-like receptor 4 (TLR4) expression, nuclear factor-κB (NF-κB) nuclear translocation and proinflammatory cytokine mRNA levels. These results indicate that CP may directly induce progressive cognitive decline and its mechanism is probably related to microbiota-gut-brain axis disorders, LPS/TLR4/NF-κB signaling activation and neuroinflammatory responses in mice. Therefore, the microbiota-gut-brain axis may provide the potential strategy for the prevention and treatment of CP-associated cognitive impairment.


Assuntos
Encefalopatias/etiologia , Periodontite Crônica/complicações , Transtornos Cognitivos/etiologia , Microbioma Gastrointestinal , Processo Alveolar/patologia , Animais , Barreira Hematoencefálica , Encefalopatias/psicologia , Doença Crônica , Periodontite Crônica/psicologia , Transtornos Cognitivos/psicologia , Citocinas/sangue , Lipopolissacarídeos/sangue , Masculino , Camundongos , NF-kappa B , Neuroglia/patologia , Neurônios/patologia , Transdução de Sinais , Sinapses/patologia , Receptor 4 Toll-Like
12.
Huan Jing Ke Xue ; 41(11): 5073-5081, 2020 Nov 08.
Artigo em Zh | MEDLINE | ID: mdl-33124250

RESUMO

Membrane fouling is the biggest challenge of membrane bioreactor industrialization. In this study, a bio-electrochemical system (BES)-anaerobic membrane bioreactor (AnMBR) system was constructed, and the effect of nano-zero-valent iron (nZVI) on membrane anti-fouling ability and methane production was investigated. The results showed that the BES-AnMBR system was stable and the chemical oxygen demand (COD) removal rate was maintained at approximately 95%. The optimum condition was observed to be nZVI 0.1 g·g-1(VS). Under this condition, transmembrane pressure (TMP) was reduced by 28.1%, the membrane flux had a slight improvement, and methane production was up to 81.3 mL·g-1(CODremoved). This was 12.1% higher than that of the control. In addition, a further analysis of extracellular polymeric substances (EPS) fraction and membrane resistance showed that nZVI enhanced EPS decomposition, promoted the formation of an iron-rich layer of inorganic and organic matters on the membrane surface, and changed the distribution of organics and inorganics, thereby significantly alleviating membrane fouling. This study will enrich basic theory of conventional AnMBR and provide a new solution for efficient sludge treatment and resource utilization.


Assuntos
Ferro , Metano , Anaerobiose , Reatores Biológicos , Membranas Artificiais , Esgotos , Eliminação de Resíduos Líquidos , Águas Residuárias
13.
Food Chem ; 331: 127277, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32544653

RESUMO

A novel nanocomposite poly(ethylene-co-vinyl acetate) (EVA) film with controlled in vitro release of iprodione (ID) was prepared. Chitosan (CS) was used as the reinforcement which enhances the water and oxygen permeability of films. ID loaded poly(ethylene glycol)-poly(ε-caprolactone) (PEG-PCL) (IPP) micelles were used as the drug carrier which endows the films with antifungal and controlled release ability. IPP micelles with spherical shape and uniform size were obtained, and the maximum encapsulation efficacy (EE) was 91.17 ± 5.03% by well controlling the feeding amount of ID. Incorporation CS could improve the oxygen and moisture permeability of films, and the maximum oxygen permeability (OP) and water vapor transmission rate (WVTR) were 477.84 ± 13.03 cc/(m2·d·0.1 MPa) and 8.60 ± 0.25 g m-2 d-1, respectively. After loading IPP micelles, the films showed an improved antifungal ability and temperature-sensitive drug release behavior, and were found to enhance the quality of grapes by pre-harvest spraying.


Assuntos
Aminoimidazol Carboxamida/análogos & derivados , Hidantoínas/farmacocinética , Nanocompostos/química , Vitis/efeitos dos fármacos , Aminoimidazol Carboxamida/administração & dosagem , Aminoimidazol Carboxamida/farmacocinética , Quitosana/química , Preparações de Ação Retardada , Portadores de Fármacos , Microbiologia de Alimentos , Fungicidas Industriais/administração & dosagem , Fungicidas Industriais/farmacocinética , Hidantoínas/administração & dosagem , Lactonas/química , Micelas , Oxigênio , Permeabilidade , Polietilenoglicóis/química , Polivinil/química , Vapor
14.
Int J Biol Macromol ; 131: 760-768, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30902714

RESUMO

Polysaccharide-modified flocculants as natural polymeric flocculants are receiving increased attention in the field of water treatment. In this study, a novel high-efficiency and ecofriendly flocculant was synthesized using dextran and chitosan. The flocculant-production method was based on a microwave-heating-initiated graft reaction. Results of Fourier transform infrared spectroscopy, nuclear magnetic resonance imaging, X-ray diffraction, elemental analysis, thermogravimetric analysis, and field-emission scanning electron microscopy confirmed that the grafting was successful. The influences of temperature, flocculant dosage, and pH on flocculation efficiency were investigated. Results indicated that 93.6% of the kaolin solid suspended particles were removed by the flocculant. Previous studies on the flocculation mechanism have shown that flocculation comprises adsorption bridging, charge neutralization, and sweeping flocculation. All these findings indicated the broad prospects of the improved dextran in treating industrial wastewater and developing novel high-performance flocculants.


Assuntos
Técnicas de Química Sintética , Quitosana/química , Dextranos/química , Micro-Ondas , Floculação , Concentração de Íons de Hidrogênio , Polímeros/síntese química , Polímeros/química , Análise Espectral , Temperatura , Termodinâmica
15.
J Biomed Nanotechnol ; 15(4): 756-768, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30841968

RESUMO

Chitosan-based hydrogels have been extensively used for tissue regeneration due to the excellent biocompatibility and biodegradability. For lack of endogenous extracellular biomacromolecules, its application is obviously limited. Because of robust biological activity, porcine small intestinal submucosa (SIS) has been considered as promising candidates to increase the bioactivity of hydrogels. Herein, a facile method for the fabrication of SIS powders (SISP)/chitosan chloride (CSCl)-ß-glycerol phosphate (GP)-hydroxyethyl cellulose (HEC) hydrogel was developed. FTIR imaging results demonstrated that SISP and CSCl could be well mixed to form porous three-dimensional SISP/CSCl composite, which underwent sol-gel phage transition from solution to non-flowing hydrogel at 37 °C. Interestingly, the sustained release of VEGF and b-FGF within the composite hydrogel was determined and no initial burst release was observed. SISP/CSCl composite supported the survival and proliferation of NIH 3T3 cells in vitro and good biocompatibility in the SD rats subcutis up to 8 weeks. Furthermore, incorporated with SISP into CSCl delayed the degradation of SISP in vivo, as characterized by histological and High-Frequency Ultrasound (HFUS) measurement. Thus, all the findings suggested that the newlydeveloped injectable and thermosensitive SISP/CSCl composite was a promising and attractive candidate for soft tissue regeneration in the minimally-invasive way.


Assuntos
Matriz Extracelular , Animais , Quitosana , Hidrogel de Polietilenoglicol-Dimetacrilato , Hidrogéis , Camundongos , Ratos , Ratos Sprague-Dawley , Engenharia Tecidual
16.
Acta Pharmacol Sin ; 29(4): 405-12, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18358085

RESUMO

AIM: N,No-[oxybis(2,1-ethanediyloxy-2,1-ethanediyl)]bis(4-methyl)- benzenesulfonamide (OMBSA) is a hit compound with potent voltage-gated K+ (Kv) channel-blocking activities that was found while searching the MDL Available Chemicals Directory with a virtual screening approach. In the present study, the blocking actions of OMBSA on Kv channels and relevant mechanisms were characterized. METHODS: Whole-cell voltage-clamp recording was made in acutely dissociated hippocampal CA1 pyramidal neurons of newborn rats. RESULTS: Superfusion of OMBSA reversibly inhibited both the delayed rectifier (I(K)) and fast transient K+ currents (I(A)) with IC50 values of 2.1+/-1.1 micromol/L and 27.8+/-1.5 micromol/L, respectively. The inhibition was voltage independent. OMBSA markedly accelerated the decay time course of IK, without a significant effect on that of I(A). OMBSA did not change the activation, steady-state inactivation of IK, and its recovery from inactivation, but the compound caused a significant hyperpolarizing shift of the voltage dependence of the steady-state inactivation of I(A) and slowed down its recovery from inactivation. Intracellular dialysis of OMBSA had no effect on both I(K) and I(A). CONCLUSION: The results demonstrate that OMBSA blocks both I(K) and I(A) through binding to the outer mouth of the channel pore, as predicted by the molecular docking model used in the virtual screening. In addition, the compound differentially moderates the inactivation kinetics of the K+ channels through allosteric mechanisms.


Assuntos
Derivados de Benzeno/farmacologia , Eletrofisiologia , Bloqueadores dos Canais de Potássio/farmacologia , Sulfonamidas/farmacologia , Animais , Animais Recém-Nascidos , Canais de Potássio de Retificação Tardia/antagonistas & inibidores , Canais de Potássio de Retificação Tardia/fisiologia , Hipocampo/citologia , Hipocampo/fisiologia , Concentração Inibidora 50 , Ativação do Canal Iônico/efeitos dos fármacos , Cinética , Estrutura Molecular , Peso Molecular , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Técnicas de Patch-Clamp , Bloqueadores dos Canais de Potássio/química , Canais de Potássio/efeitos dos fármacos , Canais de Potássio/fisiologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Células Piramidais/efeitos dos fármacos , Células Piramidais/fisiologia , Ratos , Ratos Sprague-Dawley , Sulfonamidas/química , Tetraetilamônio/farmacologia , Benzenossulfonamidas
17.
Biosens Bioelectron ; 95: 21-26, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28411533

RESUMO

An efficient near-infrared fluorescence probe has been developed for the sequential detection of Cu2+, pyrophosphate (P2O74-, PPi), and alkaline phosphatase (ALP), which is based on the "off-on-off" fluorescence switch of branched polyethyleneimine (PEI)-capped NaGdF4:Yb/Tm upconversion nanoparticles (UCNPs). The fluorescence is quenched via energy transfer from UCNPs to Cu2+ for the coordination of PEI with Cu2+. The strong affinity between Cu2+ and PPi leads to the formation of Cu2+-PPi complex and results in the detachment of Cu2+ from the surface of UCNPs, thus the fluorescence is triggered on. ALP-directed hydrolysis of PPi causes the disassembly of Cu2+-PPi complex and re-conjugation between Cu2+ with PEI, which leads to the switch-off fluorescence of UCNPs. The system allows sequential analysis of Cu2+, PPi, and ALP by modulating the switch of the fluorescence of UCNPs with detection limits of 57.8nM, 184nM, and 0.019U/mL for Cu2+, PPi, and ALP, respectively. By virtue of the NIR feature and excellent biocompatibility, the UCNPs-based probes are suitable for bioimaging. Taking Cu2+ visualization as a model, the nanoprobes have been successfully applied for intracellular imaging of Cu2+ in living cells.


Assuntos
Fosfatase Alcalina/isolamento & purificação , Técnicas Biossensoriais , Cobre/isolamento & purificação , Difosfatos/isolamento & purificação , Fosfatase Alcalina/química , Cobre/química , Difosfatos/química , Corantes Fluorescentes , Limite de Detecção , Nanopartículas/química , Polietilenoimina/química
18.
Chemosphere ; 159: 342-350, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27317940

RESUMO

Polysaccharide-modified flocculant is a notable material in the field of wastewater treatment. Synthesis of biopolysaccharide derivatives as eco-friendly flocculants is remarkably desired for environmental protection. This work presents an efficient flocculant synthesized through copolymerization of acrylamide, sodium acrylate (AS), and dextran. Physicochemical properties of the flocculant were evaluated. Process parameters of coal-washing wastewater flocculation were tested using Response Surface Method. The application of graft polymers exhibited efficient flocculation performance at low level of flocculant dosage in alkalescent environment. The improved dextran contributes to handle industrial effluent and sanitary sewage.


Assuntos
Dextranos/química , Polímeros/síntese química , Purificação da Água/instrumentação , Floculação , Polimerização , Polímeros/química , Águas Residuárias/química
20.
Chem Commun (Camb) ; 51(60): 12126-9, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26122673

RESUMO

A novel NIR-responsive GNR/LCE composite fiber material was prepared by a three-step sequential thiol-click chemistry approach. Taking advantage of GNRs' significant photo-thermal effect, a GNR/LCE composite material with a very low Au loading-level (0.09 wt%), under 808 nm NIR stimulus achieved the N-to-I transition and shrank dramatically in an ambient environment.


Assuntos
Elastômeros/química , Ouro/química , Cristais Líquidos/química , Nanotubos/química , Nanotubos/efeitos da radiação , Compostos de Sulfidrila/química , Química Click , Raios Infravermelhos , Nanocompostos/química , Nanocompostos/efeitos da radiação , Nanocompostos/ultraestrutura , Nanotubos/ultraestrutura
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