Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 96
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Pharm Res ; 41(7): 1493-1505, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38918308

RESUMO

PURPOSE: Joint destruction is a major burden and an unsolved problem in rheumatoid arthritis (RA) patients. We designed an intra-articular mesoporous silica nanosystem (MSN-TP@PDA-GlcN) with anti-inflammatory and joint protection effects. The nanosystem was synthesized by encapsulating triptolide (TP) in mesoporous silica nanoparticles and coating it with pH-sensitive polydopamine (PDA) and glucosamine (GlcN) grafting on the PDA. The nano-drug delivery system with anti-inflammatory and joint protection effects should have good potency against RA. METHODS: A template method was used to synthesize mesoporous silica (MSN). MSN-TP@PDA-GlcN was synthesized via MSN loading with TP, coating with PDA and grafting of GlcN on PDA. The drug release behavior was tested. A cellular inflammatory model and a rat RA model were used to evaluate the effects on RA. In vivo imaging and microdialysis (MD) system were used to analyze the sustained release and pharmacokinetics in RA rats. RESULTS: TMSN-TP@PDA-GlcN was stable, had good biocompatibility, and exhibited sustained release of drugs in acidic environments. It had excellent anti-inflammatory effects in vitro and in vivo. It also effectively repaired joint destruction in vivo without causing any tissue toxicity. In vivo imaging and pharmacokinetics experiments showed that the nanosystem prolonged the residence time, lowered the Cmax value and enhanced the relative bioavailability of TP. CONCLUSIONS: These results demonstrated that MSN-TP@PDA-GlcN sustained the release of drugs in inflammatory joints and produced effective anti-inflammatory and joint protection effects on RA. This study provides a new strategy for the treatment of RA.


Assuntos
Anti-Inflamatórios , Artrite Reumatoide , Diterpenos , Liberação Controlada de Fármacos , Indóis , Nanopartículas , Fenantrenos , Polímeros , Dióxido de Silício , Animais , Dióxido de Silício/química , Artrite Reumatoide/tratamento farmacológico , Nanopartículas/química , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacocinética , Fenantrenos/química , Fenantrenos/administração & dosagem , Fenantrenos/farmacocinética , Fenantrenos/farmacologia , Ratos , Diterpenos/administração & dosagem , Diterpenos/química , Diterpenos/farmacocinética , Diterpenos/farmacologia , Indóis/administração & dosagem , Indóis/química , Indóis/farmacocinética , Indóis/farmacologia , Polímeros/química , Porosidade , Masculino , Compostos de Epóxi/química , Compostos de Epóxi/administração & dosagem , Glucosamina/química , Glucosamina/administração & dosagem , Ratos Sprague-Dawley , Portadores de Fármacos/química , Humanos , Camundongos , Preparações de Ação Retardada , Inflamação/tratamento farmacológico , Inflamação/prevenção & controle
2.
Environ Sci Technol ; 58(2): 1399-1409, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38165309

RESUMO

Graphene oxide (GO) membranes enabled by subnanosized diffusion channels are promising to separate small species in membrane distillation (MD). However, the challenge of effectively excluding small volatiles in MD persists due to the severe swelling and subsequent increase in GO interlamination spacing upon direct contact with the hot feed. To address this issue, we implemented a design in which a polymer is confined between the GO interlaminations, creating predominantly 2D nanochannels centered around 0.57 nm with an average membrane pore size of 0.30 nm. Compared to the virginal GO membrane, the polymer-intercalated GO membrane exhibits superior antiswelling performance, particularly at a high feed temperature of 60 °C. Remarkably, the modified membrane exhibited a high flux of approximately 52 L m-2 h-1 and rejection rates of about 100% for small ions and 98% for volatile phenol, with a temperature difference of 40 °C. Molecular dynamics simulations suggest that the sieving mechanisms for ions and volatiles are facilitated by the narrowed nanochannels within the polymer network situated between the 2D nanochannels of GO interlaminations. Concurrently, the unrestricted permeation of water molecules through the multinanochannel GO membrane encourages high-flux desalination of complex hypersaline wastewater.


Assuntos
Destilação , Grafite , Polímeros , Difusão , Água
3.
Environ Res ; 252(Pt 1): 118881, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582430

RESUMO

Nitrate reduction in bio-electrochemical systems (BESs) has attracted wide attention due to its low sludge yields and cost-efficiency advantages. However, the high resistance of traditional electrodes is considered to limit the denitrification performance of BESs. Herein, a new graphene/polypyrrole (rGO/PPy) modified electrode is fabricated via one-step electrodeposition and used as cathode in BES for improving nitrate removal from wastewater. The formation and morphological results support the successful formation of rGO/PPy nanohybrids and confirm the part covalent bonding of Py into GO honeycomb lattices to form a three-dimensional cross-linked spatial structure. The electrochemical tests indicate that the rGO/PPy electrode outperforms the unmodified electrode due to the 3.9-fold increase in electrochemical active surface area and 6.9-fold decrease in the charge transfer resistance (Rct). Batch denitrification activity tests demonstrate that the BES equipped with modified rGO/PPy biocathode could not only achieve the full denitrification efficiency of 100% with energy recovery (15.9 × 10-2 ± 0.14 A/m2), but also favor microbial attach and growth with improved biocompatible surface. This work provides a feasible electrochemical route to fabricate and design a high-performance bioelectrode to enhance denitrification in BESs.


Assuntos
Desnitrificação , Eletrodos , Grafite , Polímeros , Pirróis , Grafite/química , Polímeros/química , Pirróis/química , Técnicas Eletroquímicas/métodos , Fontes de Energia Bioelétrica , Nitratos/química , Carbono/química , Fibra de Carbono/química
4.
J Oral Rehabil ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38873746

RESUMO

OBJECTIVE: Postoperative patients with temporomandibular joint internal derangement (ID) often have problems such as limited mouth opening and pain. Exercise therapy can be advantageous for improving the recovery of patients following surgery. However, there is continuing discussion on the precise aspects of the exercise program, including the optimal timing, length, intensity, and use of assistive equipment. Hence, this study aimed to incorporate pre-existing exercise treatment regimens and investigate their impact. METHODS: Publications that detailed the clinical treatment of patients with temporomandibular joint ID who received postoperative exercise therapy interventions were included. Nine databases were searched until October 1st, 2023. The JBI critical appraisal tools were used to assess the methodological quality of the included studies. RESULTS: Five studies were finally included for subsequent analysis; two were randomised controlled studies, and three were quasi-experimental. Exercises suitable for such patients encompass vertical, transverse, and horizontal stretching, among which vertical stretch can be divided into active and passive movements. The start time ranged from the first to the fifth week after surgery, with a duration of 1-6 months. Although the data in the studies could not be integrated and further analysed, preliminary results showed that maximum mouth opening and pain in patients improved significantly. The therapeutic effect of combining three exercise methods was best and was related to patient compliance. CONCLUSION: Exercise therapy positively affects postoperative rehabilitation in patients with temporomandibular joint ID. It is proposed that targeted, comprehensive studies be conducted to provide a basis for designing more sophisticated exercise therapy regimens and further confirm its curative effect.

5.
Opt Express ; 31(8): 12200-12211, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37157384

RESUMO

A narrow linewidth optical frequency comb (OFC) based on a directly modulated microcavity laser with external optical feedback is investigated numerically and demonstrated experimentally. Based on the numerical simulations with rate equations, the evolution of the optical and electrical spectra is presented for the direct-modulated microcavity laser with increased feedback strength, and the linewidth property is improved at suitable feedback conditions. The simulation results also show good robustness for the generated OFC in terms of feedback strength and phase. Moreover, the OFC generation experiment is performed by combining with the dual-loop feedback structure to suppress the side mode, and an OFC with a side-mode suppression ratio of 31 dB is realized. Thanks to the high electro-optical response of the microcavity laser, a 15-tone OFC with a frequency interval of 10 GHz is obtained. Finally, the linewidth of each comb tooth is measured to be around 7 kHz under the feedback power of 47 µW, which indicates an enormous compression of approximately 2000 times compared with the free-running continuous-wave microcavity laser.

6.
Int J Mol Sci ; 24(12)2023 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-37373449

RESUMO

The structure of cellulolytic enzyme lignin (CEL) prepared from three bamboo species (Neosinocalamus affinis, Bambusa lapidea, and Dendrocalamus brandisii) has been characterized by different analytical methods. The chemical composition analysis revealed a higher lignin content, up to 32.6% of B. lapidea as compared to that of N. affinis (20.7%) and D. brandisii (23.8%). The results indicated that bamboo lignin was a p-hydroxyphenyl-guaiacyl-syringyl (H-G-S) lignin associated with p-coumarates and ferulates. Advanced NMR analyses displayed that the isolated CELs were extensively acylated at the γ-carbon of the lignin side chain (with either acetate and/or p-coumarate groups). Moreover, a predominance of S over G lignin moieties was found in CELs of N. affinis and B. lapidea, with the lowest S/G ratio observed in D. brandisii lignin. Catalytic hydrogenolysis of lignin demonstrated that 4-propyl-substituted syringol/guaiacol and propanol guaiacol/syringol derived from ß-O-4' moieties, and methyl coumarate/ferulate derived from hydroxycinnamic units were identified as the six major monomeric products. We anticipate that the insights of this work could shed light on the sufficient understanding of lignin, which could open a new avenue to facilitate the efficient utilization of bamboo.


Assuntos
Bambusa , Lignina , Lignina/química , Pirogalol , Bambusa/química , Catálise
7.
Int J Mol Sci ; 24(22)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38003574

RESUMO

Pineapple color yellowing and quality promotion gradually manifest as pineapple fruit ripening progresses. To understand the molecular mechanism underlying yellowing in pineapples during ripening, coupled with alterations in fruit quality, comprehensive metabolome and transcriptome investigations were carried out. These investigations were conducted using pulp samples collected at three distinct stages of maturity: young fruit (YF), mature fruit (MF), and fully mature fruit (FMF). This study revealed a noteworthy increase in the levels of total phenols and flavones, coupled with a concurrent decline in lignin and total acid contents as the fruit transitioned from YF to FMF. Furthermore, the analysis yielded 167 differentially accumulated metabolites (DAMs) and 2194 differentially expressed genes (DEGs). Integration analysis based on DAMs and DEGs revealed that the biosynthesis of plant secondary metabolites, particularly the flavonol, flavonoid, and phenypropanoid pathways, plays a pivotal role in fruit yellowing. Additionally, RNA-seq analysis showed that structural genes, such as FLS, FNS, F3H, DFR, ANR, and GST, in the flavonoid biosynthetic pathway were upregulated, whereas the COMT, CCR, and CAD genes involved in lignin metabolism were downregulated as fruit ripening progressed. APX as well as PPO, and ACO genes related to the organic acid accumulations were upregulated and downregulated, respectively. Importantly, a comprehensive regulatory network encompassing genes that contribute to the metabolism of flavones, flavonols, lignin, and organic acids was proposed. This network sheds light on the intricate processes that underlie fruit yellowing and quality alterations. These findings enhance our understanding of the regulatory pathways governing pineapple ripening and offer valuable scientific insight into the molecular breeding of pineapples.


Assuntos
Ananas , Flavonas , Frutas/genética , Frutas/metabolismo , Transcriptoma , Ananas/metabolismo , Lignina/metabolismo , Metabolômica , Flavonoides/metabolismo , Flavonas/metabolismo , Regulação da Expressão Gênica de Plantas
8.
Phys Biol ; 19(4)2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35545074

RESUMO

Polymers are important components of the complex fluid environment for microorganisms. The mechanical effects on bacterial motile behavior due to the viscous or viscoelastic properties of polymers were extensively studied, whereas possible chemical effects on bacterial motility through bacterial chemoreception of the polymers were unclear. Here we studied the chemotactic response ofEscherichia colito polymeric solutions by combining the bead assay and FRET measurements. We found that the wild-typeE. colistrain exhibited an attractant response to widely used polymers such as Ficoll 400, polyethylene glycol (PEG) 20000 and polyvinyl pyrrolidone (PVP) 360000, and the response amplitude from chemoreception was much larger than that from the load-dependence of motor switching due to viscosity change. The chemotactic response depended on the type of receptors and the chain length of the polymers. Our findings here provided important new ingredients for further studies of bacterial motile behavior in complex fluids.


Assuntos
Polímeros , Povidona , Polímeros/química , Polímeros/farmacologia , Povidona/química , Viscosidade
9.
Mikrochim Acta ; 189(7): 250, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35680763

RESUMO

A stable ratiometric electrochemical sensor is introduced for the selective detection of carbendazim (CBD). Specifically, the proposed sensor employs a Co@Mo2C bimetallic nanomaterial as the glassy carbon electrode substrate and a layer of molecularly imprinted polymer (MIP) was in situ fabricated on glassy carbon electrode by electropolymerization, with o-aminophenol as the functional monomer and CBD acting as template. A ratiometric MIP sensor was constructed by adding ferrocene (Fc) internal reference directly to the sample solution. The bimetallic nanomaterials provide a large loading platform for the MIP layer through synergistic effects, amplifying the signal. Excellent CBD binding selectivity is achieved by the templating effect of the three-dimensional (3D) MIP layer. The internal standard is added directly to the electrolyte solution to be tested, allowing the new type of ratiometric electrochemical sensor to avoid the cumbersome steps of other methods and reducing the difficulty and human error of the experimental procedure. Combining a ratiometric strategy with a 3D MIP structure realises the dual-signal detection of CBD. The optimised sensor showed an excellent linear relationship between 0.01 and 1 000 µM, with a correlation coefficient of 0.997 and a detection limit of 3.4 nM (S/N = 3).


Assuntos
Impressão Molecular , Benzimidazóis , Carbamatos , Carbono/química , Técnicas Eletroquímicas/métodos , Humanos , Limite de Detecção , Impressão Molecular/métodos , Polímeros Molecularmente Impressos , Polímeros/química
10.
J Anim Ecol ; 90(6): 1455-1465, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33666233

RESUMO

Animal choruses, such as those found in insects and frogs, are often intermittent. Thus, females sampling males in the chorus might have to remember the location of the potential mates' calls during periods of silence. Although a number of studies have shown that frogs use and prefer multimodal mating signals, usually acoustic plus visual, it is not clear why they do so. Here we tested the hypothesis that preference for multimodal signals over unimodal signals might be due to multimodal signals instantiating longer memories than unimodal signals, particularly during the inter-chorus intervals. We tested this hypothesis in serrate-legged small treefrogs Kurixalus odontotarsus whose males produce advertisement calls accompanied by conspicuous vocal sac inflation. Females were tested with acoustic and acoustic + visual (video of inflating-deflating vocal sac) mating calls. We found that females prefer multimodal calls over unimodal, audio-only calls. Furthermore, multimodal calls are still preferred after a silent period of up to 30 s, a time that spans the average silent period of the chorus. This was not true of unimodal calls. Our results demonstrate that a multimodal signal can engage longer working memory than a unimodal signal, and thus female memory might favour the evolution of multimodal signals in males through sexual selection. Selection might also favour female preference for multimodal signals if longer memory facilitates mate searching and assessment. Our study does not allow us to elucidate the sequence of evolution of this trait and preference.


Assuntos
Preferência de Acasalamento Animal , Vocalização Animal , Animais , Anuros , Feminino , Masculino , Memória de Curto Prazo , Comportamento Sexual Animal
11.
Cell Biol Int ; 45(8): 1733-1742, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33851759

RESUMO

The nerve conduits have been developed for nerve defect repair. However, no artificial conduits have obtained comparable results to autografts to bridge the large gaps. A possible reason for this poor performance may be a lack of sustainable neurotrophic support for axonal regrowth. Previous studies suggested nanocomposite conduits can be used as a carrier for valproic acid (VPA), a common drug that can produce effects similar to the neurotrophic factors. Here, we developed the novel bioabsorbable conduits based on hydroxyapatite/poly d-l-lactic acid (PDLLA)/poly{(lactic acid)-co-[(glycolic acid)-alt-(l-lysine)]} with sustained release of VPA. Firstly, the sustained release of VPA in this conduit was examined by high-performance liquid chromatography. Then Schwann cells were treated with the conduit extracts. The cell metabolic activity and proliferation were assayed by 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2-tetrazolium bromide and bromodeoxyuridine staining. A 10-mm segment of rat sciatic nerve was resected and then repaired, respectively, using the VPA conduit (Group A), the PDLLA conduit (Group B), or the autografts (Group C). Nerve conduction velocities (NCVs), compound muscle action potentials (CMAPs), and histological staining were assayed following the surgery. The cell metabolic activity and proliferation were significantly increased (p < .05) by the extracts from VPA-conduit extract compared to others. NCVs and CMAPs were significantly higher in Groups A and C than Group B (p < .05). The nerve density of Groups A and C was higher than Group B. There was no significant difference between Groups A and C. Taken together, this study suggested the sustained-release VPA conduit promoted peripheral nerve regeneration that was comparable to the autografts. It holds potential for future use in nerve regeneration.


Assuntos
Materiais Biocompatíveis/farmacocinética , Durapatita/farmacocinética , Regeneração Nervosa/efeitos dos fármacos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacocinética , Nervo Isquiático/efeitos dos fármacos , Ácido Valproico/farmacocinética , Animais , Animais Recém-Nascidos , Materiais Biocompatíveis/administração & dosagem , Células Cultivadas , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Liberação Controlada de Fármacos/efeitos dos fármacos , Liberação Controlada de Fármacos/fisiologia , Durapatita/administração & dosagem , Masculino , Regeneração Nervosa/fisiologia , Poliésteres/administração & dosagem , Poliésteres/farmacocinética , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/administração & dosagem , Ratos , Ratos Wistar , Células de Schwann/efeitos dos fármacos , Células de Schwann/metabolismo , Nervo Isquiático/metabolismo , Ácido Valproico/administração & dosagem
12.
J Mater Sci Mater Med ; 32(6): 72, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34125310

RESUMO

To find out the optimal porosity and pore size of porous titanium (Ti) regarding the cytocompatibility and osteogenic differentiation. Six groups of porous Ti samples with different porosities and pore sizes were fabricated by the powder metallurgy process. The microstructure and compressive mechanical properties were characterized. The cytocompatibility was examined by a series of biological tests as protein absorption with BCA assay kit, cell attachment with laser scanning confocal microscopy and vinculin expression, cell proliferation with CCK-8 assay. Cell differentiation and calcification were detected by qPCR and Alizarin Red S dying respectively. Pores distributed homogeneously throughout the porous Ti samples. The compressive test results showed that Young's modulus ranged from 2.80 ± 0.03 GPa to 5.43 ± 0.34 GPa and the compressive strength increased from 112.4 ± 3.6 MPa to 231.1 ± 9.4 MPa. Porous Ti with high porosity (53.3 ± 1.2%) and small pore size (191.6 ± 3.7 µm) adsorbed more proteins. More MC3T3-E1 cells adhered onto dense Ti samples than onto any other porous ones already after culture and no difference was identified within the porous groups. The porous structure of porous Ti with a porosity of 53.3 ± 1.2% and an average pore size of 191.6 ± 3.7 µm facilitated cell differentiation and calcification. Small pores were not beneficial to the osteo-initiation at the very beginning. Porous Ti with a porosity of 53.3 ± 1.2% and an average pore size of 191.6 ± 3.7 µm fabricated by powder metallurgy process showed the expected mechanical property and improved osseointegration as implants in dental treatment.


Assuntos
Força Compressiva , Teste de Materiais/métodos , Osteogênese/efeitos dos fármacos , Titânio/química , Células 3T3 , Adsorção , Ligas/química , Animais , Materiais Biocompatíveis/química , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células , Células Cultivadas , Módulo de Elasticidade , Camundongos , Osseointegração/efeitos dos fármacos , Porosidade , Estresse Mecânico
13.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(3): 416-422, 2021 May.
Artigo em Zh | MEDLINE | ID: mdl-34018359

RESUMO

OBJECTIVE: To investigate the influence of Runt-related transcription factor 1 (RUNX1) on the proliferation, osteogenic differentiation and adipogenic differentiation of dental pulp stem cells (DPSC) in vitro. METHODS: DPSCs were transfected through lentiviral vector carrying the target gene RUNX1 and green fluorescent protein (GFP). After 48 h, transfection efficiency was determined with the fluorescent marking of GFP and Western blot. The effect of the overexpression of RUNX1 on DPSC proliferation and colony formation was determined with CCK-8 and colony formation assay; cell cycle of DPSC was detected by flow cytometry. RUNX1 siRNA was transfected into the DPSCs. After mineralized induction, the effect of RUNX1 overexpression/silencing on the osteogenetic differentiation of DPSC was tested by alkaline phosphatase (ALP) staining and alizarin red staining. After adipogenic induction, oil red O staining was done in order to observe the effect of overexpression/silencing of RUNX1 on the adipogenic differentiation of DPSC. RESULTS: RUNX1 protein was overexpressed in DPSC after lentiviral transfection. Fluorescent test showed successful transfection of lentiviral transfection and over 70% of the cells showed stable expression of GFP protein. The proliferation and colony-formation efficiency of DPSC was enhanced significantly and the proportion of DPSCs in the S phase was significantly increased in the RUNX1-overexpessed group ( P<0.05). ALP activity and mineralized nodule formation ability increased, while lipid droplets decreased in the RUNX1-overexpessed group ( P<0.05). ALP activity and mineralized nodule formation ability decreased, while lipid droplets increased in the RUNX1 knockdown group ( P<0.05) . CONCLUSION: RUNX1 promotes DPSC proliferation and osteogenic differentiation while it inhibits DPSC adipogenic differentiation.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core , Osteogênese , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Polpa Dentária , Células-Tronco
14.
Water Sci Technol ; 82(10): 2098-2113, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33263587

RESUMO

In this study, an excellent phosphate adsorbent was prepared for removing phosphate to an extremely low concentration. The La(OH)3 nano-rods stabilizing in polyacrylonitrile (PAN) nanofibers (PLNFs) were prepared by electrospinning and a subsequent in situ precipitation. PAN nanofibers were employed as the matrix of the composite nanofibers, where the well-dispersed La(OH)3 nano-rods were encapsulated as the active species for highly efficient phosphate capture owing to the strong binding between phosphate and lanthanum. On account of the nano-structure, the maximum phosphate adsorption capacity was 151.98 mg P/g (La), much higher than the result of La(OH)3 nano-crystal, produced by precipitation without PAN or any organic surfactants. Moreover, the PLNFs could remove phosphate (2 mg P/L) to an extremely low concentration within 20 min, which could lead to a nutrient deficient condition to protect water quality and ecosystem. The optimization of PLNFs design was implemented through parameter adjustment of electrospinning. Lanthanum salt content, humidity, concentration of solution and applied voltage were chosen to analyze the influences on the composition, diameter and morphology of the nanofibers, giving the result that the most effective adsorbent was the PLNFs with spider-web-like nano-structures.


Assuntos
Lantânio , Nanofibras , Resinas Acrílicas , Adsorção , Ecossistema , Fosfatos
15.
Anal Chem ; 91(23): 15275-15283, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31674180

RESUMO

Photoacoustic (PA) imaging as a noninvasive biomedical imaging technology exhibits high spatial resolution and deep tissue penetration for in vivo imaging. In order to fully explore the potential of PA imaging in biomedical applications, new contrast agents with improved PA stability and efficiency are in high demand. Herein, we present a new PA agent based on an oxygen-embedded quinoidal nonacene chromophore that is self-assembled into nanoparticles (Nano(O-Nonacene)-PEG), assisted by polyethylene glycol (PEG). Notably, the photothermal conversion efficiency of Nano(O-Nonacene)-PEG is 1.5 fold that of semiconducting polymer nanoparticles (Nano(PCPDTBT)-PEG) and 2.8 fold that of Au nanorods, owing to the low quantum yield of Nano(O-Nonacene)-PEG. Thereby, Nano(O-Nonacene)-PEG possess a greatly elevated PA signal intensity, compared to Nano(PCPDTBT)-PEG and Au nanorods, which have been widely explored for PA imaging. Due to the high resistance to photo bleaching, Nano(O-Nonacene)-PEG exhibits higher PA signal stability, which may be employed for long-term PA imaging. Moreover, when magnetic Zn0.4Fe2.6O4 nanoparticles are incorporated into Nano(O-Nonacene)-PEG, not only are magnetic resonance signals generated but also the photoacoustic efficacy is greatly enhanced. Therefore, Nano(O-Nonacene)-PEG offers distinct properties: (i) the elevated photoacoustic effect allows for high-resolution photoacoustic imaging, (ii) small size (10 nm in diameter) results in efficient tumor-targeting, and (iii) the facile application of efficient photothermal therapy in vivo. The current work offers the possibility of oxygen-embedded quinoidal acene as a promising PA probe for precision phototheranostics.


Assuntos
Imagem Molecular , Sondas Moleculares/química , Nanopartículas/química , Oxigênio/química , Técnicas Fotoacústicas , Fototerapia , Quinonas/química , Estrutura Molecular , Tamanho da Partícula , Polietilenoglicóis/química , Semicondutores , Propriedades de Superfície
16.
Pulm Pharmacol Ther ; 55: 50-61, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30738974

RESUMO

Pulmonary delivery of anti-cancer drugs in the form of nanoparticulate dry powders is considered a promising modality for treating lung cancer. However, it is not known whether the pharmacodynamics and pharmacokinetics of nano-preparations are altered after co-spray drying. In this study, we compared the physicochemical property, anti-cancer activity, tumor targeting and pharmacokinetic behavior of docetaxel-loaded folic acid-conjugated liposomes (LPs-DTX-FA) with those of dry powder prepared by co-spray-drying LPs-DTX-FA. The particle size and PDI after re-dispersion of the powder were increased. The re-dispersed liposomes showed increased cellular uptake via micropinocytosis and exhibited higher cytotoxicity than LPs-DTX-FA. Tumor targeting of re-dispersed liposomes was less effective compared with LPs-DTX-FA but the metabolism of re-dispersed liposomes was decreased. Tracheal administration resulted in a 45-fold higher concentration of docetaxel in the lung of Sprague Dawley rats at 30 min as compared with intravenous administration. Our results indicated that co-spray drying did change the properties, while tracheal administration of the dry powder provided higher drug exposure at the tumor site without increasing the exposure of other organs. Thus, inhaled dry powders might be clinically effective for treatment of lung cancer.


Assuntos
Antineoplásicos/administração & dosagem , Docetaxel/administração & dosagem , Ácido Fólico/química , Neoplasias Pulmonares/tratamento farmacológico , Administração por Inalação , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Docetaxel/química , Docetaxel/farmacocinética , Sistemas de Liberação de Medicamentos , Inaladores de Pó Seco , Lipossomos , Masculino , Tamanho da Partícula , Pós , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
17.
Environ Sci Technol ; 53(2): 1014-1021, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30540452

RESUMO

A novel anaerobic treatment system that combines the impact of applied voltage with membrane filtration over carbon nanotubes hollow fiber membranes (CNTs-HFMs) was developed at low temperature (15-20 °C) to mitigate membrane fouling, treat wastewater, and recover energy (CH4). Herein, electro-assisted CNTs-HFMs served a dual function as the cathode and membrane filtration. In contrast with other two anaerobic membrane bioreactors (AnMBRs; polyvinylidene fluoride hollow fiber membranes and CNTs-HFMs without electro-assistance), the CNTs-HFMs with electro-assistance (-1.2 V applied voltage) had slower transmembrane pressure (TMP) increasing rates and better TMP recovery with a more than 95% effluent chemical oxygen demand (COD) removal rate during an almost 100-day operation period. This result can be attributed to the presence of an electrostatic repulsion force pushing pollutants (mainly extracellular polymeric substances, EPS) away from the membrane surface, thereby hindering the formation of a gel layer and mitigating membrane pore blocking in the anaerobic electro-assisted membrane bioreactor (AnEMBR). Due to the almost two-times higher Methanomicrobia content and more H2-utilizing methanogens than the other two AnMBRs, approximately more than 111.12 mL/gVSS d of CH4 was obtained in the AnEMBR with electro-assistance. This work provides an efficient strategy for mitigating membrane fouling, improving water quality, and enhancing CH4 yield.


Assuntos
Nanotubos de Carbono , Purificação da Água , Anaerobiose , Reatores Biológicos , Eletrodos , Membranas Artificiais , Eliminação de Resíduos Líquidos , Águas Residuárias
18.
Cardiovasc Diabetol ; 17(1): 114, 2018 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-30107794

RESUMO

BACKGROUND: To improve outcomes in patients with diabetes mellitus (DM) undergoing percutaneous coronary intervention remain an unmet clinical need. The study aimed to evaluate the efficacy and safety of G2-DESs and BP-DESs in patients with and without DM in a single center in China. METHODS: A total of 7666 consecutive patients who exclusively had G2-DES or BP-DES implantation throughout 2013 in our center were studied. The primary efficacy endpoint was any target lesion revascularization (TLR), whereas the primary safety endpoint was a composite of death or myocardial infarction (MI) at 2-year follow-up. RESULTS: G2-DESs had a similar occurrence of death, non-fatal MI, TLR, stroke, and stent thrombosis compared with BP-DESs in patients with DM (all P > 0.05). The incidence of TVR and TLR was lower for G2-DESs than for BP-DESs in patients without DM (3.2% vs. 5.1%, P = 0.002; 2.2% vs. 4.5%, P < 0.001, respectively). Kaplan-Meier analysis also showed better TVR- and TLR-free survival rates for G2-DESs than for BP-DESs in patients without DM. Multivariate analysis showed that a BP-DES was an independent risk factor for TLR (hazard ratio 1.963, 95% confidence interval 1.390-2.772, P < 0.001) in patients without DM, which was not predictive of other components of major adverse cardiac events (P > 0.05). CONCLUSIONS: G2-DESs have better efficacy, represented by a reduced risk of TLR, and similar safety compared with BP-DESs in patients without DM. G2-DESs have similar efficacy and safety compared with BP-DESs in patients with DM at 2-year follow-up.


Assuntos
Implantes Absorvíveis , Fármacos Cardiovasculares/administração & dosagem , Doença da Artéria Coronariana/cirurgia , Diabetes Mellitus/epidemiologia , Stents Farmacológicos , Intervenção Coronária Percutânea/instrumentação , Polímeros/química , China/epidemiologia , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/mortalidade , Humanos , Incidência , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Estudos Prospectivos , Desenho de Prótese , Recidiva , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Fatores de Tempo , Resultado do Tratamento
19.
Biomacromolecules ; 19(6): 2182-2193, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29669209

RESUMO

Reactive oxygen species (ROS)-responsive polymers have attracted attention for their potential in photodynamic therapy. Herein, we report the ROS-responsive aliphatic polycarbonates prepared by the ring-opening polymerization (ROP) of three six-membered cyclic carbonate monomers with ethyl selenide, phenyl selenide or ethyl telluride groups. Under catalysis of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), all three monomers underwent the controlled anionic ROP, showing a feature of equilibrium polymerization due to the bulky effect of 5,5-disubstituents. With PEG macroinitiator, three series amphiphilic block copolymers were prepared. They could form spherical nanoparticles of ∼100 nm, which were stable in neutral phosphate buffer but dissociated rapidly under triggering of H2O2. We studied the H2O2-induced oxidation profiles of selenide- or telluride-containing small molecules by 1H NMR and revealed the factors that affect the oxidation kinetics and products. On this basis, the oxidative degradation mechanism of the copolymer nanoparticles has been clarified. Under the same oxidative condition, the telluride-containing nanoparticle degraded with the fastest rate while the phenyl selenide-based one degraded most slowly. These ROS-responsive nanoparticles could load photosensitizer chlorin e6 (Ce6) and anticancer drug doxorubicin (DOX). Under red light irradiation, Ce6-sensitized production of 1O2 that triggered the degradation of nanoparticles, resulting in an accelerated payload release. In vitro cytotoxicity assays demonstrate that the nanoparticles coloaded with DOX and Ce6 exhibited a synergistic cell-killing effect to MCF-7 cells, representing a novel responsive nanoplatform for PDT and/or chemotherapy.


Assuntos
Peróxido de Hidrogênio , Nanopartículas , Neoplasias/tratamento farmacológico , Fotoquimioterapia , Cimento de Policarboxilato , Clorofilídeos , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/farmacocinética , Peróxido de Hidrogênio/farmacologia , Células MCF-7 , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias/metabolismo , Neoplasias/patologia , Cimento de Policarboxilato/química , Cimento de Policarboxilato/farmacocinética , Cimento de Policarboxilato/farmacologia , Porfirinas/química , Porfirinas/farmacocinética , Porfirinas/farmacologia
20.
J Oral Maxillofac Surg ; 75(3): 641-647, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27669373

RESUMO

PURPOSE: Relevant reports about oral candidiasis status and prevention measures after free flap surgery for the oral and maxillofacial region are limited. The present study explored oral candidiasis status after free flap surgery and its prevention through a prospective comparative study. PATIENTS AND METHODS: One hundred four patients were randomized to a control group (n = 54) and an experimental group (n = 50). Compared with the control group, the experimental group was provided an additional 3% sodium bicarbonate saline solution for oral care after free flap surgery. The incidence of oral candidiasis was evaluated by objective examination (saliva culture and salivary pH measurement) and subjective evaluation (clinical signs of oral candidiasis) at admission and from postoperative days 1 to 14. RESULTS: The salivary pH values of the 2 groups were lower than the normal salivary pH, and postoperative salivary pH values were always lower than the active range of oral lysozymes in the control group. The salivary pH values of the experimental group were higher than those of the control group from postoperative days 6 to 14 (P < .05). The incidence of oral candidiasis was 13.0% in the control group, which was higher than that in the experimental group (2.0%; P < .05). In addition, advanced age, use of a free flap for the simultaneous repair of intraoral and paraoral defects, and a combination of 2 antibiotic types were risk factors for oral candidiasis. CONCLUSION: Oral candidiasis was common in patients after free flap reconstruction surgery, and the use of 3% sodium bicarbonate saline solution for oral care effectively prevented it.


Assuntos
Candidíase Bucal/prevenção & controle , Retalhos de Tecido Biológico , Procedimentos Cirúrgicos Bucais , Bicarbonato de Sódio/administração & dosagem , Administração Oral , Candidíase Bucal/epidemiologia , Feminino , Humanos , Concentração de Íons de Hidrogênio , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Saliva/microbiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA