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1.
J Med Virol ; 95(7): e28915, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37417384

RESUMO

Infection of the central nervous system caused by enterovirus 71 (EV71) remains the main cause of death in hand-foot-and-mouth disease. However, the mechanism responsible for how EV71 breaks through the blood-brain barrier to infect brain cells has yet to be elucidated. By performing a high-throughput small interfering RNA (siRNA) screening and validation, we found that the infection of human brain microvascular endothelial cells (HBMECs) by EV71 was independent of the endocytosis pathways mediated by caveolin, clathrin, and macropinocytosis but dependent on ADP-ribosylation factor 6 (ARF6), a small guanosinetriphosphate (GTP)-binding protein of the Ras superfamily. The specific siRNA targeting ARF6 markedly inhibited HBMECs susceptibility to EV71. EV71 infectivity was inhibited by NAV-2729, a specific inhibitor of ARF6, in a dose-dependent manner. The subcellular analysis demonstrated the co-localization of the endocytosed EV71 and ARF6, while knockdown of ARF6 with siRNA remarkably influenced EV71 endocytosis. By immunoprecipitation assays, we found a direct interaction of ARF6 with EV71 viral protein. Furthermore, ARF1, another small GTP-binding protein, was also found to participate in ARF6-mediated EV71 endocytosis. Murine experiments demonstrated that NAV-2729 significantly alleviated mortality caused by EV71 infection. Our study revealed a new pathway by which EV71 enters the HBMECs and provides new targets for drug development.


Assuntos
Fator 6 de Ribosilação do ADP , Enterovirus Humano A , Infecções por Enterovirus , Animais , Humanos , Camundongos , Fator 6 de Ribosilação do ADP/metabolismo , Encéfalo/metabolismo , Células Endoteliais , Enterovirus Humano A/genética , RNA Interferente Pequeno/genética
2.
Langmuir ; 38(19): 6086-6098, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35504860

RESUMO

Oceanic oil spill and the discharge of industrial oily wastewaters can cause significant threats to the ecological environment and human health. Herein, we design a durable TiO2/PDA-based superhydrophobic paper for efficient oil/water separation. Bioinspired from mussel adhesive proteins, the mechanical durability of the as-prepared superhydrophobic paper is enhanced by the deposition of polydopamine (PDA) onto cellulosic fibers via self-polymerization of dopamine. The TiO2/PDA-based superhydrophobic paper shows a high water contact angle of 168.2° and an oil contact angle of ∼0°, exhibiting excellent superhydrophobicity and superoleophilicity. Furthermore, the as-prepared superhydrophobic paper possesses excellent chemical stability, thermal stability, and mechanical durability in terms of being immersed in corrosive solutions and solvents and boiling water and being subjected to the sandpaper abrasion test, respectively. More importantly, the separation efficiency of the TiO2/PDA-based superhydrophobic paper for an oil/water mixture is 97.2%, and it maintains a separation efficiency above 94.3% even after 15 cyclic separation processes. Furthermore, the separation efficiency for water-in-oil emulsions is higher than 93.7% after 15 cyclic separation tests, showing its excellent recyclable stability for water-in-oil emulsions. Therefore, the rationally designed TiO2/PDA-based superhydrophobic paper shows great potential in the practical applications of self-cleaning, antifouling, and oil/water separation.


Assuntos
Polímeros , Emulsões , Humanos , Interações Hidrofóbicas e Hidrofílicas , Indóis , Polímeros/química , Titânio
3.
Int J Mol Sci ; 19(6)2018 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-29895809

RESUMO

Poly (methyl methacrylate) (PMMA)-based bone cements are the most commonly used injectable orthopedic materials due to their excellent injectability and mechanical properties. However, their poor biocompatibility and excessive stiffness may cause complications such as aseptic implant loosening and stress shielding. In this study, we aimed to develop a new type of partially biodegradable composite bone cement by incorporating magnesium (Mg) microspheres, known as "Mg sacrifices" (MgSs), in the PMMA matrix. Being sensitive to the physiological environment, the MgSs in PMMA could gradually degrade to produce bioactive Mg ions and, meanwhile, result in an interconnected macroporous structure within the cement matrix. The mechanical properties, solidification, and biocompatibility, both in vitro and in vivo, of PMMA⁻Mg bone cement were characterized. Interestingly, the incorporation of Mg microspheres did not markedly affect the mechanical strength of bone cement. However, the maximum temperature upon setting of bone cement decreased. This partially biodegradable composite bone cement showed good biocompatibility in vitro. In the in vivo study, considerable bony ingrowth occurred in the pores upon MgS degradation. Together, the findings from this study indicate that such partially biodegradable PMMA⁻Mg composite may be ideal bone cement for minimally invasive orthopedic surgeries such as vertebroplasty and kyphoplasty.


Assuntos
Cimentos Ósseos/química , Polimetil Metacrilato/química , Magnésio/química , Osseointegração/fisiologia , Temperatura
4.
Int J Biol Macromol ; 260(Pt 2): 129569, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38253151

RESUMO

Frequent oceanic oil spill incidents and the discharge of industrial oily wastewaters have caused serious threats to environments, food chains and human beings. Lignin wastes with many reactive groups exist as the byproducts from bioethanol and pulping processing industries, and they are either discarded as wastes or directly consumed as a fuel. To make full use of lignin wastes and simultaneously deal with oily wastewaters, porous lignin-based composites have been rationally designed and prepared. In this review, recent advances in the preparation of porous lignin-based composites are summarized in terms of aerogels, sponges, foams, papers, and membranes, respectively. Then, the mechanisms and the application of porous lignin-based adsorbents and filtration materials for oil/water separation are discussed. Finally, the challenges and perspectives of porous lignin-based composites are proposed in the field of oil/water separation. The utilization of abundant lignin wastes can replace fossil resources, and meanwhile porous lignin-based composites can be used to efficiently treat with oily wastewaters. The above utilization strategy opens an avenue to the rational design and preparation of lignin wastes with high-added value, and gives a possible solution to use lignin wastes in a sustainable and environmentally friendly way.


Assuntos
Líquidos Corporais , Lignina , Humanos , Porosidade , Águas Residuárias , Filtração
5.
Chemistry ; 19(33): 10935-44, 2013 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-23818407

RESUMO

Self-assembled poly(N-methylaniline)-lignosulfonate (PNMA-LS) composite spheres with reactive silver-ion adsorbability were prepared from N-methylaniline by using lignosulfonate (LS) as a dispersant. The results show that the PNMA-LS composite consisted of spheres with good size distribution and an average diameter of 1.03-1.27 µm, and the spheres were assembled by their final nanofibers with an average diameter of 19-34 nm. The PNMA-LS composite spheres exhibit excellent silver-ion adsorption; the maximum adsorption capacity of silver ions is up to 2.16 g g(-1) at an adsorption temperature of 308 K. TEM and wide-angle X-ray results of the PNMA-LS composite spheres after absorption of silver ions show that silver ions are reduced to silver nanoparticles with a mean diameter of about 11.2 nm through a redox reaction between the PNMA-LS composite and the silver ions. The main adsorption mechanism between the PNMA-LS composite and the silver ions is chelation and redox adsorption. In particular, a ternary PNMA-LS-Ag composite achieved by using the reducing reaction between PNMA-LS composite spheres and silver ions can be used as an antibacterial material with high bactericidal rate of 99.95 and 99.99% for Escherichia coli and Staphylococcus aureus cells, respectively.


Assuntos
Compostos de Anilina/química , Antibacterianos/química , Lignina/análogos & derivados , Polímeros/química , Prata/química , Adsorção , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Íons/química , Lignina/química , Nanofibras/química , Staphylococcus aureus/efeitos dos fármacos
6.
PLoS One ; 18(2): e0281513, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36800384

RESUMO

This study investigates the fractal characteristics of the particle size and shape distribution of gangue powder in the "jaw crushing-ball milling" process using mudstone gangue. For this, fractal theory, laser particle size analyzer, scanning electron microscope and other mesoscopic research methods were introduced. This study has several main factors, including the discharge port width in the jaw crushing stage, the grinding particle size, ball-to-powder ratio in the ball milling stage, and the fractal dimension changes of the gangue in different crushing stages. The results indicate that in the process of "jaw crushing-ball milling", gangue's particle size and shape fractal dimension values changed periodically. During the jaw crushing stage, the particle size fractal dimension increases with the width of the discharge opening, ranging from 1.85 to 1.92. The value of the shape fractal dimension varies from 2.65 to 2.84. Ball milling causes the fractal dimension value of gangue particle size to increase with time before agglomeration and decrease after agglomeration. By comparing different in-grinding particle sizes and ball-to-powder ratio, it is found that the fractal dimension value of gangue particle size decreases with the increase of in-grinding particle size and increases with the increase of ball-to-powder ratio. The final gangue's particle size fractal dimension value is concentrated between 2.5 and 2.8. The fractal dimension of particle shape increases with the increase of the grinding particle size, and decreases with the increase of ball-to-powder ratio. A ball-to-powder ratio greater than 6 gradually reduces its influence on fractal dimensions, and the final shape dimension lies between 1.06 and 1.16. In addition, the increase/decrease range of particle size and shape fractal dimension decreases with the increase of ball milling time, which is also consistent with the grinding kinetics theory. As a result of the changes in particle size and shape fractal dimensions, parameters such as jaw crusher discharge port width, grinding particle size, and ball-to-powder ratio are calculated to provide a theoretical basis for the entire crushing process in the "jaw crusher-ball milling" crushing process.


Assuntos
Fractais , Modelo Transteórico , Pós , Tamanho da Partícula
7.
Chemistry ; 18(51): 16571-9, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23109322

RESUMO

Electroconductive poly(N-butylaniline)-lignosulfonate (PBA-LS) composite nanospheres were prepared in a facile way by in situ, unstirred polymerization of N-butylaniline with lignosulfonate (LS) as a dispersant and dopant. The LS content was used to optimize the size, structure, electroconductivity, solubility, and silver ion adsorptive capacity of the PBA-LS nanospheres. Uniform PBA-LS10 nanospheres with a minimal mean diameter of 375 nm and high stability were obtained when the LS content was 10 wt %. The PBA-LS10 nanospheres possess an increased electroconductivity of 0.109 S cm(-1) compared with that of poly(N-butylaniline) (0.0751 S cm(-1)). Furthermore, the PBA-LS10 nanospheres have a maximal silver-ion sorption capacity of 815.0 mg g(-1) at an initial silver ion concentration of 50 mmol L(-1) (25 °C for 48 h), an enhancement of 70.4% compared with PBA. Moreover, a sorption mechanism of silver ions on the PBA-LS10 nanospheres is proposed. TEM and wide-angle X-ray diffraction results showed that silver nanoparticles with a diameter size range of 6.8-55 nm was achieved after sorption, indicating that the PBA-LS10 nanospheres had high reductibility for silver ions.


Assuntos
Íons/química , Lignina/análogos & derivados , Nanopartículas/química , Nanosferas/química , Prata/química , Adsorção , Lignina/química , Estrutura Molecular , Espectrofotometria Infravermelho
8.
J Knee Surg ; 35(14): 1577-1586, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33992032

RESUMO

Pneumatic tourniquets are used in total knee arthroplasty (TKA) for surgical field visualization and improved cementation; however, their use is controversial. This study aimed to assess the effects of tourniquet application on faster recovery post-TKA. Our hypothesis was that inflammation and limb function would be similar with different tourniquet applications. A prospective randomized double-blinded trial assessed tourniquets effects on postoperative pain, swelling, and early outcome in TKA. In present study, 50 TKAs were enrolled in each group as follows: full course (FC), cementation through closure (CTC), and no tourniquet (NT), CTC as treatment group while FC and NT as control groups. Topical blood samples of 3 mL from the joint cavity and drainage bags were obtained at special time point. At last, all samples such as tumor necrosis factor-a (TNF-a), C-C motif chemokine ligand 2 (CCL2), pentraxin 3 (PTX3), prostaglandin E2 (PGE2), superoxide dismutase 1 (SOD1), and myoglobin (Mb) were detected by ELISA. Active and passive range of motion (ROM) values, pain score by the visual analog scale (VAS), change of thigh circumference were recorded at special time point as well. In topical blood, the change of inflammatory factors, such as TNF-a, PTX3, CCL2, PGE2, SOD1, and Mb, was lower in CTC and NT groups than in FC group (p < 0.01 and 0.05). Although VAS and ROM were comparable preoperatively in three groups (p > 0.05), the perimeter growth rate was lower, pain scores (VAS) were reduced, and ROM values were improved in CTC and NT groups compared with FC group at T4, T5, and T6 postoperatively (p < 0.01 and 0.05). Improved therapeutic outcome was observed in the CTC group, indicating patients should routinely undergo TKA with cementation through closure tourniquet application.


Assuntos
Artroplastia do Joelho , Humanos , Cimentação , Estudos Prospectivos , Dinoprostona , Superóxido Dismutase-1 , Perda Sanguínea Cirúrgica , Dor Pós-Operatória/etiologia , Isquemia , Reperfusão , Torniquetes , Amplitude de Movimento Articular
9.
Medicine (Baltimore) ; 98(35): e16895, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31464920

RESUMO

RATIONALE: Methotrexate (MTX) is an antimetabolite of folic acid, which is used for management of ectopic pregnancy. MTX-related toxicity may include cutaneous mucosal damage, bone marrow suppression, gastrointestinal disorders (gastritis, diarrhea, hematitis), liver and kidney function damage, pulmonary toxicity, cardiac toxicity, and nerve toxicity. However, it is not usual for vulvar edema induced by low-dose methotrexate. PATIENT CONCERNS: In this case report, we described a patient with severe vulvar edema and oral cavity ulceration and scalp ulceration induced by low-dose MTX treatment for ectopic pregnancy. Her presenting complaints were pain in the vulva, oral cavity, and scalp. DIAGNOSES: The patient was diagnosed based on clinical findings for MTX toxic reactions. INTERVENTIONS: Vulva was disinfectioned with iodide and Kangfuxin solution, her mouth was rinsed with mouthwash. Three compound glycyrrhizin tablets were orally administered (3 times/day). After 10 days, the broken skin and mucous membrane healed. OUTCOMES: The vulvar edema and oral cavity ulceration and scalp ulceration healed. LESSONS: Our study demonstrated that even low-dose MTX can be induced skin and mucosal injury, patients and doctors should timely detection of drug toxicity reactions, immediately rescue, prompt discontinuation of medication, and symptomatic treatment to avoid accidental occurrence.


Assuntos
Metotrexato/administração & dosagem , Metronidazol/administração & dosagem , Gravidez Ectópica/tratamento farmacológico , Vaginite por Trichomonas/tratamento farmacológico , Doenças da Vulva/induzido quimicamente , Dor Abdominal/etiologia , Administração Oral , Adulto , China , Feminino , Ácido Glicirrízico/administração & dosagem , Ácido Glicirrízico/uso terapêutico , Humanos , Injeções Intramusculares , Materia Medica/administração & dosagem , Materia Medica/uso terapêutico , Metotrexato/efeitos adversos , Metronidazol/uso terapêutico , Gravidez , Gravidez Ectópica/diagnóstico , Resultado do Tratamento , Hemorragia Uterina/etiologia , Doenças da Vulva/tratamento farmacológico
10.
Int J Nanomedicine ; 13: 7183-7193, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519015

RESUMO

BACKGROUND: Bone cement plays an important role in the treatment of osteoporotic vertebral compression fractures. Calcium phosphate cement (CPC) is a potential alternative to poly(methyl methacrylate), currently the gold standard of bone cements. However, the poor mechanical properties of CPCs limit their clinical applications. The objective of this study was to develop reinforced CPCs for minimally invasive orthopedic surgeries by compositing silk fibroin (SF) with α-tricalcium phosphate. METHODS: SF solution was treated with calcium hydroxide and characterized by Zeta potential analyzer and Fourier transform infrared spectroscopy. The alkaline-treated SF (tSF) was com-posited with α-tricalcium phosphate to obtain tSF/CPC composite, which was characterized using mechanical tests, scanning electron microscopy, handling property and biocompatibility tests, and sheep vertebral augmentation tests. RESULTS: Upon treatment with calcium hydroxide, larger SF particles and more abundant negative charge appeared in tSF solution. The tSF/CPCs exhibited a compact structure, which consisted of numerous SF -CPC clusters and needle-like hydroxyapatite (HAp) crystals. In addition, high transition rate of HAp in tSF/CPCs was achieved. As a result, the mechanical property of tSF/ CPC composite cements was enhanced remarkably, with the compressive strength reaching as high as 56.3±1.1 MPa. Moreover, the tSF/CPC cements showed good injectability, anti-washout property, and decent biocompatibility. The tSF/CPCs could be used to augment defected sheep vertebrae to restore their mechanical strength. CONCLUSION: tSF/CPC may be a promising composite bone cement for minimally invasive orthopedic surgeries.


Assuntos
Álcalis/farmacologia , Cimentos Ósseos/química , Fosfatos de Cálcio/química , Fibroínas/química , Animais , Materiais Biocompatíveis/química , Bombyx , Linhagem Celular , Proliferação de Células , Força Compressiva , Difusão Dinâmica da Luz , Concentração de Íons de Hidrogênio , Camundongos , Ovinos , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Coluna Vertebral/efeitos dos fármacos , Coluna Vertebral/fisiologia , Eletricidade Estática , Difração de Raios X
11.
Shanghai Kou Qiang Yi Xue ; 24(1): 56-60, 2015 Feb.
Artigo em Zh | MEDLINE | ID: mdl-25858371

RESUMO

PURPOSE: To explore whether p38 signal pathway regulates osteogenic differentiation of maxillary primordium mesenchymal cells. METHODS: The first passage of maxillary primordium mesenchymal cells (MPMCs) from E12.5 embryos were cultured in the osteogenic medium, and 10 nM SB203580 (an inhibitor of phosphorylation of p38) was added in the medium in the experimental group for 1 week. Then immunofluorescence staining was applied to detect the phosphorylation of p38 in MPMCs. Brdu label and immunofluorescence staining were used to detect the proliferation of MPMCs. ALP staining and qPCR were used to detect the mRNA expression of ALP, Runx2, OCN and OPN in MPMCs. ALP staining and PCR were used to evaluate the osteogenic capability of MPMCs. SPSS 18.0 software package was used to analyze the data. RESULTS: Osteogenic induction could promote phosphorylation of p38, inhibit phosphorylation of p38 and proliferation of MPMCs, down-regulate the expression of ALP, Runx2, OCN and OPN, thus weaken the ALP staining in MPMCs. CONCLUSIONS: p38 signal pathway regulates osteogenic differentiation of MPMCs in vitro.


Assuntos
Diferenciação Celular , Sistema de Sinalização das MAP Quinases , Células-Tronco Mesenquimais , Osteogênese , Animais , Proliferação de Células , Embrião de Mamíferos , Maxila , Camundongos
12.
J Biomed Mater Res A ; 102(1): 68-75, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23606446

RESUMO

Calcium phosphate cement (CPC) has been widely used in orthopedic and dental applications. A critical limitation of CPC is low strength and high susceptibility to severe fracture. Surgeons can use it only to reconstruct non-stress bearing bone, raising the need for a tougher new generation of CPC. Fibers have been used as a reinforcement of CPC to improve the strength of a pure CPC scaffold. The RGD peptides (Arg-Gly-Asp) have been used to improve the biocompatibility of the scaffold, via physical adsorption. The purpose of this study was to develop a novel CPC scaffold reinforced by RGD peptide-bearing chitosan fibers (RGD-fiber-CPC). Our data showed that the RGD-fiber-CPC scaffold had an increased flexural strength, and stimulated new bone formation in an animal model. The RGD-fiber-CPC is a novel bone graft substitute in orthopedic surgery.


Assuntos
Substitutos Ósseos , Fosfatos de Cálcio , Quitosana , Cimentos Dentários , Oligopeptídeos , Osteogênese/efeitos dos fármacos , Animais , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Linhagem Celular , Quitosana/química , Quitosana/farmacologia , Cimentos Dentários/química , Cimentos Dentários/farmacologia , Camundongos , Oligopeptídeos/química , Oligopeptídeos/farmacologia
13.
Bioresour Technol ; 127: 66-71, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23131624

RESUMO

Lignosulfonate/poly(2-ethylaniline) (LS-PEA) composite nanospheres were prepared via in situ polymerization of 2-ethylaniline (EA) with lignosulfonate (LS) as a dispersant. LS-PEA nanospheres with an average diameter of 155 nm were obtained at an optimal LS concentration of 20 wt.%. Subsequently, nitrogen-containing carbon nanospheres were fabricated via direct pyrolysis of the LS-PEA composite nanospheres at 600-800 °C. The carbon nanospheres prepared by pyrolysis were used as anodes of lithium-ion batteries. The first charge and discharge capacity of carbon nanospheres prepared at 700 °C at current densities of 60 and 100 mA g(-1) were 980 and 432 mAh g(-1), and 764 and 342 mAh g(-1), respectively. The batteries still owned a high capacity of 353 and 296 mAh g(-1) after 20 cycles. The results indicated that these nitrogen-containing carbon nanospheres could be used as a promising candidate for electrode materials of lithium-ion batteries.


Assuntos
Compostos de Anilina/química , Carbono/análise , Eletrodos , Temperatura Alta , Lignina/análogos & derivados , Nanoestruturas/análise , Nitrogênio/análise , Carbono/química , Fontes de Energia Elétrica , Eletroquímica , Lignina/química , Nanoestruturas/química
14.
Int J Biol Macromol ; 51(5): 946-52, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22863891

RESUMO

Novel poly(N-ethylaniline)/lignosulfonate (PNA-LS) composites were prepared via an in situ polymerization of N-ethylaniline (NA) with lignosulfonate (LS) as a dispersant. Nitrogen-containing carbon materials were obtained by direct pyrolysis of the PNA-LS composites at the pyrolytic temperatures ranging from 300°C to 1200°C. The as-prepared PNA-LS composites and their carbon materials were investigated by TGA, SEM, TEM, FTIR and UV-vis spectra, XRD and elemental analysis. The results showed that the morphology, structure and properties of the PNA-LS composites were depended on the LS:NA mass ratio. PNA-LS microspheres with an average diameter of 1300 nm could be fabricated when the LS:NA mass ratio was 2.5:97.5, while regular hexagon sheets of PNA-LS composite were obtained with the LS:NA mass ratio above 5:95. Furthermore, nitrogen-containing carbon nanospheres with an average diameter of 820 nm were achieved at the carbonization temperature of 800°C.


Assuntos
Compostos de Anilina/química , Carbono/química , Lignina/análogos & derivados , Microesferas , Polímeros/química , Condutividade Elétrica , Lignina/química , Polimerização , Solubilidade
15.
ACS Appl Mater Interfaces ; 4(1): 369-74, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22195637

RESUMO

A hierarchical polyaniline-lignin (PANI-EHL) composite was facilely prepared from aniline and enzymatic hydrolysis lignin in an aqueous solution of ammonia. The morphology, FTIR, UV-vis spectra, thermogravimetric analysis, and wide-angle X-ray diffraction analyses of the composite were systematically investigated. Furthermore, the sorption property of the PANI-EHL composite for silver ions in aqueous solution was studied via a static sorption technique. The result demonstrated that the PANI-EHL composite possessed a strongly reactive sorption characteristic for silver ions. Serrated silver threads with length up to 10 mm were obtained by using the PANI-EHL composite as a low-cost adsorbent. Moreover, the role of EHL and polyaniline in the PANI-EHL composite for silver ions sorption was investigated. The investigation indicated that the EHL unit could play a vital role in the chelation of silver ions, whereas the polyaniline unit played a leading role in redox sorption.


Assuntos
Compostos de Anilina/química , Recuperação e Remediação Ambiental/instrumentação , Íons/química , Lignina/química , Prata/química , Poluentes Químicos da Água/química , Adsorção
16.
Biomed Mater ; 7(4): 045003, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22556166

RESUMO

Infection remains a serious medical problem in orthopaedic surgery. Antibiotic administration can be available either systemically via the blood stream or locally, directly into the infected bone. One of the main limitations of antibiotic administration is the development of multi-antibiotic-resistant bacterial strains. In this study, we developed bactericidal calcium phosphate cements (CPC) by incorporation of different molecular weight chitosan and hydroxypropyltrimethyl ammonium chloride chitosan (HACC). Two standard strains, S. epidermidis (ATCC35984) and S. aureus (ATCC25923), and one clinical isolate, methicillin-resistant S. epidermidis (MRSE), were selected to evaluate the antibacterial activity of these bone cements. Our data showed that the CPC loaded with low molecular weight chitosan and HACC significantly inhibited the bacterial adhesion and biofilm formation. In addition, HACC-containing CPC has no cytotoxic effects on both mouse pluripotent C3H10T1/2cell line and a murine L929 fibroblast cell line. We propose that HACC-containing CPC represents a promising polymer-based bactericidal bone scaffold in controlling orthopaedic surgery-related infection.


Assuntos
Anti-Infecciosos/química , Materiais Biocompatíveis/química , Cimentos Ósseos/farmacologia , Fosfatos de Cálcio/química , Animais , Aderência Bacteriana , Cimentos Ósseos/química , Linhagem Celular , Quitosana/análogos & derivados , Quitosana/química , Desenho de Fármacos , Fibroblastos/citologia , Camundongos , Camundongos Endogâmicos C3H , Microscopia Confocal/métodos , Peso Molecular , Compostos de Amônio Quaternário/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos
17.
Int J Nanomedicine ; 6: 241-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21499422

RESUMO

BACKGROUND: The purpose of this study was to develop a transdermal ligustrazine patch containing a stable formulation and with good entrapment efficiency, release rate, and transdermal absorption. METHODS: Ligustrazine ethosomes were prepared by ethanol injection-sonication, with entrapment efficiency as an indicator. Using acrylic resin as the primary constituent, the ligustrazine ethosome patch was prepared by adding succinic acid as a crosslinking agent and triethyl citrate as a plasticizer. In vitro release and transdermal permeation studies were carried out. Finally, a pharmacokinetic study was carried out in rats to explore relative bioavailability. The formulations of ligustrazine ethosome were 1% (w/v) phospholipid, 0.4% (w/v) cholesterol, and 45% (v/v) ethanol. RESULTS: Ligustrazine ethosomes were obtained with an average particle size of 78.71 ± 1.23 nm and an average entrapment efficiency of 86.42% ± 1.50%. In vitro transdermal testing of the ligustrazine ethosome patches showed that the cumulative 24-hour amount of ligustrazine was up to 183 ± 18 µg/cm(2). The pharmacokinetic results revealed that the relative bioavailability was 209.45%. CONCLUSION: Compared with conventional ligustrazine administration, ligustrazine ethosome patches could promote better drug absorption and increase bioavailability. This study demonstrates that the transdermal action of the ligustrazine ethosome patch was comparatively good.


Assuntos
Pirazinas/administração & dosagem , Adesivo Transdérmico , Animais , Disponibilidade Biológica , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Humanos , Lipossomos/administração & dosagem , Lipossomos/química , Masculino , Nanomedicina , Tamanho da Partícula , Pirazinas/sangue , Pirazinas/farmacocinética , Ratos , Ratos Sprague-Dawley , Vasodilatadores/administração & dosagem , Vasodilatadores/sangue , Vasodilatadores/farmacocinética
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