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1.
J Prosthet Dent ; 124(6): 799.e1-799.e5, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33039186

RESUMO

STATEMENT OF PROBLEM: The separation of a denture liner from the denture base can be a clinical problem. Different surface treatments to increase the bond have been evaluated, but studies comparing the effect of argon plasma and erbium-doped yttrium aluminum garnet (Er:YAG) laser on the bond between acrylic resin and a denture liner are lacking. PURPOSE: The purpose of this in vitro study was to evaluate the effect of argon plasma and Er:YAG laser treatments on the bond strengths of acrylic resin to 2 denture liners. MATERIALS AND METHODS: Heat-polymerized acrylic resin (Acron Duo) was bonded to silicone soft-liner materials (Molloplast B, n=30; Mollosil, n=30) to create control specimens (n=10), argon plasma treatment (n=10), and Er:YAG laser treatment (n=10). Silicone liners were polymerized on resin specimens. The tensile bond strength test was performed with a crosshead speed of 10 mm/min with a 10-N load until failure. Data were analyzed by using the Kruskal-Wallis test and unpaired t test (α=.05). RESULTS: The laser group showed significantly higher bond strength than the argon plasma group for both Molloplast-B (P=.001) and Mollosil (P<.001). The highest tensile bond strength values were determined in the laser-treated Molloplast-B group (1.325 ±0.119 MPa) while the lowest bond strength values were determined in the Mollosil control group (0.384 ±0.018 MPa). CONCLUSIONS: Argon plasma and Er:YAG laser applications increases the tensile bond strength between soft-liner material and resin. Er:YAG laser treatment results in higher bond strength values than treatment with argon plasma for 1 minute.


Assuntos
Colagem Dentária , Reembasadores de Dentadura , Lasers de Estado Sólido , Gases em Plasma , Resinas Acrílicas , Argônio , Bases de Dentadura , Teste de Materiais , Propriedades de Superfície , Resistência à Tração
2.
J Microencapsul ; 36(7): 635-648, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31509450

RESUMO

In this study, the anticancer activities of two siRNA carriers were compared using a human lung adenocarcinoma epithelial cell line (A549). Firstly, poly(styrene)-graft-poly(linoleic acid) (PS-g-PLina) and poly(styrene)-graft-poly(linoleic acid)-graft-poly(ethylene glycol) (PS-g-PLina-g-PEG) graft copolymers were synthesized by free-radical polymerization. PS-PLina and PS-PLina-PEG nanoparticles (NPs) were prepared by solvent evaporation method and were then characterized. The size was found as 150 ± 10 nm for PS-PLina and 184 ± 6 nm for PS-PLina-PEG NPs. The NPs were functionalized with poly(l-lysine) (PLL) for c-myc siRNA conjugation. siRNA entrapment efficiencies were found in the range of 4-63% for PS-PLina-PLL and 6-42% for PS-PLina-PEG-PLL NPs. The short-term stability test was realised for 1 month. siRNA release profiles were also investigated. In vitro anticancer activity of siRNA-NPs was determined by MTT, flow cytometry, and fluorescence microscopy analyses. Obtained findings showed that both NPs systems were promising as siRNA delivery tool for lung cancer therapy.


Assuntos
Adenocarcinoma de Pulmão/terapia , Neoplasias Pulmonares/terapia , Nanoconjugados/química , Óleos de Plantas/química , RNA Interferente Pequeno/uso terapêutico , Células A549 , Adenocarcinoma de Pulmão/genética , Portadores de Fármacos/química , Humanos , Ácido Linoleico/química , Neoplasias Pulmonares/genética , Polietilenoglicóis/química , Poliestirenos/química , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Terapêutica com RNAi
3.
Prep Biochem Biotechnol ; 49(7): 659-670, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31066619

RESUMO

Small interfering RNA (siRNA)-based gene silencing strategy has high potential on suppressing specific molecular targets, involved in cancer progression. However, the lack of an effective nanocarrier system that safely delivers siRNA to its target still limits the clinical applications of siRNA. This study aimed to develop albumin-sericin nanoparticles (Alb-Ser NPs) as a novel siRNA delivery system for laryngeal cancer treatment. Nanoparticle formulations composed of albumin and sericin at different ratios (1:1, 2:1, 1:2 w/w) were synthesized by desolvation method. The nanoparticles were modified with poly-L-lysine (PLL) for siRNA binding and decorated with hyaluronic acid (HA) to target laryngeal cancer cell line, Hep-2. HA/PLL/Alb-Ser NPs were individually loaded with siRNAs for casein kinase 2 (CK2), Absent, Small, or Homeotic-Like (ASH2L), and Cyclin D1 genes, which are overexpressed in Hep-2 cells. Downregulation of genes was confirmed by real-time PCR (RT-PCR). Size, morphological, and thermogravimetric characterizations revealed that Alb-Ser NPs having 2:1 (w/w) ratio are the most optimized formulation. Between 36.8 and 61.3% of siRNA entrapment efficiencies were achieved. HA/PLL-siRNA/Alb-Ser (2:1) NPs-mediated gene silencing resulted in a significant inhibition of cell growth and induction of apoptosis in cells. Our findings showed that HA/PLL/Alb-Ser (2:1) NPs were promising as a siRNA carrier.


Assuntos
Técnicas de Transferência de Genes , Neoplasias Laríngeas/terapia , Nanopartículas/química , RNA Interferente Pequeno/administração & dosagem , Terapêutica com RNAi , Sericinas/química , Albumina Sérica Humana/química , Caseína Quinase II/genética , Linhagem Celular Tumoral , Ciclina D1/genética , Proteínas de Ligação a DNA/genética , Portadores de Fármacos/química , Humanos , Neoplasias Laríngeas/genética , Nanopartículas/ultraestrutura , Proteínas Nucleares/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/uso terapêutico , Terapêutica com RNAi/métodos , Fatores de Transcrição/genética
4.
Prep Biochem Biotechnol ; 48(7): 610-618, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29902111

RESUMO

In the present study, culture conditions of Streptococcus equi was optimized through Box-Behnken experimental design for hyaluronic acid production. About 0.87 gL-1 of hyaluronic acid was produced under the determined conditions and optimal conditions were found as 38.42 °C, 24 hr and 250 rpm. The validity and practicability of this statistical optimization strategy were confirmed relation between predicted and experimental values. The hyaluronic acid obtained under optimal conditions was characterized. The effects of different conditions such as ultraviolet light, temperature and enzymatic degradation on hyaluronic acid produced under optimal conditions were determined. 118 °C for 32 min of autoclaved HA sample included 63.09 µg mL-1 of d-glucuronic acid, which is about two-fold of enzymatic effect. Cytotoxicity of hyaluronic acid on human dermal cells (HUVEC, HaCaT), L929 and THP-1 cells was studied. In vitro effect on pro or anti-inflammatory cytokine release of THP-1 cells was determined. Although it varies depending on the concentration, cytotoxicity of hyaluronic acid is between 5 and 30%. However, it varies depending on the concentration of hyaluronic acid, TNF-α release was not much increased compared to control study. Consequently, purification procedure is necessary to develop and it is worth developing the bacterial hyaluronic acid.

5.
BMC Surg ; 17(1): 40, 2017 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-28416010

RESUMO

BACKGROUND: An incisional hernia is a common complication following abdominal surgery. Polypropylene mesh is frequently used in the repair of such defects and has nearly become the standard surgical treatment modality. Though they are very effective in reducing recurrence, mesh materials exhibit a strong stimulating effect for intraabdominal adhesion. The thymoquinone (TQ) extracted from Nigella sativa seeds has potential medical properties. TQ has anti-inflammatory, antioxidant and antibacterial properties. The aim of this study is to coat polypropylene mesh with TQ in order to investigate the effect of surface modification on intraabdominal adhesions. METHODS: TQ-coated polypropylene mesh material was tested for cytotoxicity, contact angle, surface spectroscopy, TQ content, sterility, and electron microscopic surface properties. An experimental incisional hernia model was created in study groups, each consisting of 12 female Wistar rats. The defect was closed with uncoated mesh in control group, with polylactic acid (PLA) coated mesh and PLA-TQ coated mesh in study groups. Adhesion scores and histopathologic properties were evaluated after sacrifice on postoperative 21th day. RESULTS: Granuloma formation, lymphocyte and polymorphonuclear leukocyte infiltration, histiocyte fibroblast and giant cell formation, capillary infiltration, collagen content were significantly reduced in the PLA-TQ coated mesh group (p < 0.05). Though not statistically significant, likely due to the limited number of study animals, adhesion formation was also reduced in the PLA-TQ coated mesh group (p: 0.067). CONCLUSION: TQ coated mesh is shown to reduce adhesion formation and TQ is a promising coating material for mesh surface modification.


Assuntos
Benzoquinonas/química , Polipropilenos/química , Telas Cirúrgicas , Aderências Teciduais/prevenção & controle , Adesivos , Animais , Colágeno/metabolismo , Feminino , Poliésteres/química , Ratos , Ratos Wistar , Aderências Teciduais/etiologia
6.
J Microencapsul ; 33(3): 274-85, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27049468

RESUMO

The aim of this study was to evaluate therapeutic potential of curcumin-loaded poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) PHBHHx nanoparticles (CUR-NPs) and concanavaline A conjugated curcumin-loaded NPs (ConA-CUR-NPs) for breast cancer treatment. The size and zeta potential of prepared NPs were about 228 ± 5 nm and -23.3 mV, respectively. The entrapment efficiencies of polymer/drug weight ratios, 1.25CUR-NPs, 2.5CUR-NPs, 5CUR-NPs, ConA-1.25CUR-NPs, ConA-2.5CUR-NPs and ConA-5CUR-NPs were found to be ≈68, 55, 45, 70, 60 and 51%, respectively. Optimized NPs formulations in the freeze-dried form were assessed with their short-term stability for 30 days of storage at 4 °C and 25 °C. Anticancer activity of ConA-CUR-NPs was proved by MTT assay and reconfirmed by double staining and flow cytometry results. The anticancer activity of ConA-CUR-NPs was measured in human breast cancer cells (MDA-MB 231) in vitro, and the results revealed that the ConA-CUR-NPs had better tumor cells decline activity.


Assuntos
Ácido 3-Hidroxibutírico/química , Antineoplásicos/administração & dosagem , Caproatos/química , Concanavalina A/química , Curcumina/administração & dosagem , Nanopartículas/química , Antineoplásicos/farmacologia , Mama/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Canavalia/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Curcumina/farmacologia , Preparações de Ação Retardada/química , Portadores de Fármacos/química , Feminino , Humanos
7.
Int J Neurosci ; 124(9): 685-96, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24350993

RESUMO

This study is designed to evaluate the treatment effect of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) and human mesenchymal stem cells (hMSC) on axonal regeneration in experimental rat sciatic nerve damage, and compare the results of this modality with autologous nerve grafting. In Spraque-Dawley albino rats, 10-mm-long experimental nerve gaps were created. Three groups were constituted, the gap was repaired with autologous nerve graft (autograft group), PHBHHx nerve graft alone (PHBHHx alone group), and PHBHHx nerve graft with hMSCs inside (PHBHHx with hMSC group), respectively. The results were evaluated with functional recovery, electrophysiological evaluation, and histological evaluation either with light microscopy and transmission electron microscopy for axonal regeneration and myelin formation. In functional evaluation, autograft and PHBHHx with hMSC groups showed functional improvement with time, whereas PHBHHx alone group did not. Electrophysiological evaluation showed better results in autograft and PHBHHx with hMSC groups when compared to PHBHHx alone group. There was no statistical difference between autograft and PHBHHx with hMSC groups. Histological evaluation showed regenerated axons in each group. Autograft group was better than the others, and PHBHHx with hMSC group was better than PHBHHx alone group both for axonal regeneration and myelin formation. This study showed that the nerve grafts which were prepared from PHBHHx with oriented nanofiber three-dimensional surfaces aided to nerve regeneration, either used alone or with hMSC. PHBHHx provided better nerve regeneration when used with hMSCs inside than alone, and reached the same statistical treatment effect in functional evaluation and electrophysiological evaluation when compared to autografting.


Assuntos
Ácido 3-Hidroxibutírico/farmacologia , Ácido 3-Hidroxibutírico/uso terapêutico , Caproatos/farmacologia , Caproatos/uso terapêutico , Transplante de Células-Tronco Mesenquimais , Regeneração Nervosa/efeitos dos fármacos , Neuropatia Ciática/tratamento farmacológico , Neuropatia Ciática/cirurgia , Animais , Axônios/patologia , Axônios/ultraestrutura , Células Cultivadas , Modelos Animais de Doenças , Eletromiografia , Potencial Evocado Motor/efeitos dos fármacos , Feminino , Humanos , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Células-Tronco Mesenquimais/fisiologia , Células-Tronco Mesenquimais/ultraestrutura , Microscopia Eletrônica de Varredura , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Fibras Nervosas Mielinizadas/patologia , Fibras Nervosas Mielinizadas/ultraestrutura , Regeneração Nervosa/fisiologia , Ratos , Ratos Sprague-Dawley
8.
Biomacromolecules ; 12(12): 4291-300, 2011 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-22044242

RESUMO

In this work, we utilize a recently developed microbubbling process to generate controlled protein (bovine serum albumin, BSA) coated bubbles and then manipulate these to fabricate a variety of structures suitable for several generic biomedical applications, tissue engineering, and biosensor coatings. Using BSA solutions with varying concentrations (20, 25, and 30 wt %) and cross-linking (terephthaloyl chloride) mechanisms, structures were fabricated including porous thin films with variable pore sizes and thickness (partially cross-linked coupled to bubble breakdown), scaffolds with variable pore morphologies (fully cross-linked), and coated bubbles (no cross-linking), which can be used as stand-alone delivery devices and contrast agents. The movement of typical biosensor chemicals (catechol and hydrogen peroxide) across appropriate film structures was studied. The potential of formed scaffold structures for tissue engineering applications was demonstrated using mouse cell lines (L929). In addition to low cost, providing uniform structure generation and high output, the size of the bubbles can easily be controlled by adjusting simplistic processing parameters. The combination of robust processing and chemical modification to uniform macromolecule bubbles can be utilized as a competing, yet novel, tool with current technologies and processes in advancing the biomaterials and biomedical engineering remits.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Microbolhas , Soroalbumina Bovina/química , Engenharia Tecidual/métodos , Animais , Técnicas Biossensoriais , Catecóis/metabolismo , Linhagem Celular , Sistemas de Liberação de Medicamentos , Etanol/farmacologia , Peróxido de Hidrogênio/metabolismo , Membranas/química , Camundongos , Ácidos Ftálicos , Alicerces Teciduais
9.
Turk Neurosurg ; 31(2): 189-198, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33575995

RESUMO

AIM: To examine the implantation of chitosan channels stuffed with mesenchyme-originated stem/progenitor cells (MSPCs) derived from adult rats in a spinal cord transection model. The level of axonal regeneration, the effect of chitosan channels on the survival of MSPCs, and the functional recovery results were also evaluated. MATERIAL AND METHODS: Chitosan channels stuffed with MSPCs were implanted at the level of T8 in a transected rat spinal cord. MSPCs were harvested from the pelvic bone marrow of adult rats, and the MSPC?chitosan channel group was compared with three control groups. The axonal regeneration capacity, the effect of chitosan channels on the survival of MSPCs, and the functional recovery results were compared among four groups. The survival of MSPCs was evaluated using histopathological techniques and electron microscopy, axonal regeneration/germination was evaluated by confocal microscopy, and locomotor function was assessed for 4 weeks using the Basso, Beattie, and Bresnahan locomotor score. RESULTS: The MSPC-chitosan channel group exhibited enhanced survival of transplanted MSPCs compared with MSPCs transplanted directly into the lesion cavity, although no significant difference was detected in locomotor function between the treatment and control groups. The MSPC-chitosan channel group demonstrated thicker myelination of axons than the other groups. CONCLUSION: Chitosan channels promoted the survival of transplanted MSPCs and created a tissue bridge after complete spinal cord transection. They also induced axonal regeneration and germination. No significant improvement in functional recovery was found between the groups.


Assuntos
Axônios/fisiologia , Materiais Biocompatíveis/administração & dosagem , Quitosana/administração & dosagem , Transplante de Células-Tronco Mesenquimais/métodos , Regeneração Nervosa/fisiologia , Traumatismos da Medula Espinal/terapia , Animais , Feminino , Células-Tronco Mesenquimais/fisiologia , Mesoderma , Regeneração Nervosa/efeitos dos fármacos , Ratos , Ratos Wistar , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/patologia
10.
Turk Neurosurg ; 20(3): 286-94, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20669100

RESUMO

AIM: The objective of this study was to investigate whether the transplantation of fetal umbilical cord tissue cells as a source of stem cells into the acutely injured spinal cord would produce some regenerations and/or functional recovery in a rat model of spinal cord injury. MATERIAL AND METHODS: Five pregnant albino Wistar rats of 12 days gestation were used for obtaining an umbilical cord cell graft. At the second stage of the experiment only Th8-Th9 laminectomy was performed in Group A animals while Group B animals underwent spinal cord hemitransection. The cultured fetal umbilical cord cells coated with Alginate Gel were placed into the lesion cavity immediately after surgery in Group C animals. Group D animals received only Alginate gel sponges into the injured area. All experiment groups were analyzed histologically and immunohistochemically (GFAP, Ki-67, and Pan cadherin) and for motor function after surgery. RESULTS: The umbilical cord cell transplanted animals showed a significant motor recovery compared to non-transplanted animals at 8 and 21 days after spinal cord injury (p=0.008). Significant GFAP and Ki-67 expressions were noted in transplanted animals (p=0.048) suggesting astroglial proliferation. CONCLUSION: Our findings support the possibility of some functional recovery after umbilical cord cell transplantation following spinal cord injury.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical/veterinária , Atividade Motora/fisiologia , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/cirurgia , Transplante Homólogo/métodos , Animais , Divisão Celular , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Feminino , Membro Posterior/fisiologia , Músculo Esquelético/fisiologia , Gravidez , Ratos , Ratos Wistar , Traumatismos da Medula Espinal/patologia , Transplante Homólogo/veterinária , Tripsina , Cordão Umbilical/citologia , Caminhada/fisiologia
11.
Colloids Surf B Biointerfaces ; 196: 111340, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32956996

RESUMO

With the development of nanotechnology, various drug delivery systems including inorganic nanoparticles, liposomes, polymers, etc. have been developed over the past decade. Some of these nanoparticles are also forthcoming candidates for the successful delivery of small interfering RNA (siRNA) for targeted gene silencing. Upon its discovery, siRNA was perceived as a highly promising agent in the treatment of various diseases. However, it could not exhibit the expected clinical outcomes owing to the unfavorable challenges during delivery. One such challenge was identified as the lack of an effective carrier. Among the carriers, calcium phosphate (CaP) nanoparticles have attracted remarkable attention due to the superior biochemical properties and hold great promise for siRNA. It is well known that synthesis conditions influence the types of crystalline phases of CaPs as well as morphology. In this study, to address the influence of these parameters on the success of siRNA delivery, three different arginine (Arg) modified CaP nanoparticles having different chemical and morphological characteristics were synthesized as being the carriers of two specific siRNAs against survivin and cyclin B1. The functioning of CaP surfaces with Arg results in positive zeta potential on the surfaces. Functionalized nanoparticles have a higher loading capacity compared to unmodified particles, as they have a cationic surface that can be easily attached to negatively charged siRNAs. The gene silencing ability and the consequent in vitro antitumor activity of these CaP-Arg-siRNA complexes were investigated using A549 non-small-cell lung cancer cells. We found that high survivin and cyclin B1 expression is associated with worse survival in patients with lung cancer based on the Kaplan-Meier database. Considering the promoting role of survivin and cyclin B1 in cancer development and progression, CaP-Arg-siRNA mediated suppression of these genes resulted in a significant decrease in cell growth and induction of apoptosis. Our data suggest that all three CaP-Arg nanoparticles synthesized in this work can be used as safe and efficient nanocarriers for siRNA delivery, offering the opportunity to develop new therapeutic strategies for the treatment of lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Nanopartículas , Arginina , Fosfatos de Cálcio , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Ciclina B1/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , RNA Interferente Pequeno/genética , Survivina/genética
12.
IET Nanobiotechnol ; 14(7): 617-622, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33010138

RESUMO

This study aimed to develop sorafenib loaded magnetic microspheres for the treatment of hepatocellular carcinoma. To achieve this goal, superparamagnetic iron oxide nanoparticles (SPIONs) were synthesised and encapsulated in alginate microspheres together with an antineoplastic agent, sorafenib. In the study, firstly SPIONs were synthesised and characterised by dynamic light scattering, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. Then, alginate-SPIONs microspheres were developed, and further characterised by electron spin resonance spectrometer and vibrating sample magnetometer. Besides the magnetic properties of SPIONs, alginate microspheres with SPIONs were also found to have magnetic properties. The potential use of microspheres in hyperthermia treatment was then investigated and an increase of about 4°C in the environment was found out. Drug release studies and cytotoxicity tests were performed after sorafenib was encapsulated into the magnetic microspheres. According to release studies, sorafenib has been released from microspheres for 8 h. Cytotoxicity tests showed that alginate-SPION-sorafenib microspheres were highly effective against cancerous cells and promising for cancer therapy.


Assuntos
Alginatos/química , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Microesferas , Sorafenibe/química , Animais , Antineoplásicos/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Espectroscopia de Ressonância de Spin Eletrônica , Compostos Férricos/química , Células Hep G2 , Humanos , Hipertermia , Técnicas In Vitro , Luz , Magnetismo , Nanopartículas de Magnetita/química , Nanopartículas Metálicas/química , Camundongos , Neoplasias/metabolismo , Tamanho da Partícula , Pós , Espalhamento de Radiação , Temperatura , Espectroscopia por Absorção de Raios X
13.
J Hazard Mater ; 162(2-3): 1073-80, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18620805

RESUMO

Polyethyleneglycolmethacrylate (PEGMA) and vinylimidazole (VI) were used in order to obtain microspheres of PEGMA-VI copolymers that can be used in heavy metal removal applications. The obtained copolymers were characterized and their use as sorbents in heavy metal removal was investigated. In the first part of the study, PEGMA-VI microspheres were prepared by suspension polymerization method. The obtained swellable microspheres with 10-50 microm average diameter did not have permanent porosity according to the morphological and physicochemical determinations. The sizes of microspheres became smaller with increasing VI and cross-linker ethyleneglycoldimethacrylate (EGDMA) contents and increasing agitation rate. The VI content, EGDMA ratio, pH and ionic strength were determined as the effective parameters on the swelling behavior of PEGMA-VI microspheres. In the second part of the study, Cu(II) ions were used as a model species in order to investigate the usability of the obtained PEGMA-VI microspheres in heavy metal removal. Adsorption capacities under optimum conditions were determined. The Cu(II) ion adsorption capacity increased by increasing the initial Cu(II) ion concentration, and it reached the maximum value (i.e., 30 mg Cu(II)/g PEGMA-VI microspheres) at 400 mg Cu(II)/L initial Cu(II) ion concentration under the determined optimum conditions. Microspheres were found to be reusable after desorption for several times.


Assuntos
Metais Pesados/isolamento & purificação , Polietilenoglicóis/química , Polivinil/química , Adsorção , Microesferas
14.
Mater Sci Eng C Mater Biol Appl ; 102: 756-763, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31147048

RESUMO

Degenerative cartilage is the pathology of severe depletion of extracellular matrix components in articular cartilage. In diseases like osteoarthritis, misregulation of microRNAs contributes the pathology and collectively leads to disruption of the homeostasis. In this study chondroitin sulfate/hyaluronic acid/chitosan nanoparticles were prepared and successfully characterized chemically and morphologically. Results demonstrated higher chondroitin sulfate amounts led smaller nanoparticles, but lower surface zeta potential due to high electronegativity. After optimization of chondroitin sulfate amounts regarding size and charge, nanoparticles were loaded with microRNA-149-5p, a therapeutic miRNA downregulated in osteoarthritis, and evaluated focusing on their loading efficiency, release behaviour, cytotoxicity and gene transfection efficiency in vitro. Results showed all nanoparticle formulations were non-toxic and promising gene delivery agents, due to increased levels of microRNA-149-5p and decreased mRNA levels of microRNA's target, FUT-1. Highest gene transfection efficiency was obtained with the nanoparticle formulation which had the highest chondroitin sulfate load and smallest size. In addition, owing to their high chondroitin sulfate cargo, all nanoparticles were reported to enhance chondrogenesis, which was demonstrated by gene expression analysis and sulfated glycosaminoglycan (sGAG) staining. The obtained data suggest that the delivery of microRNA-149-5p via polysaccharide based carriers could achieve collaborative impact in cartilage regeneration and have a potential to enhance osteoarthritis treatment.


Assuntos
Condrogênese , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/metabolismo , Nanopartículas/química , Polissacarídeos/química , Morte Celular , Quitosana , Sulfatos de Condroitina/química , Difusão Dinâmica da Luz , Regulação da Expressão Gênica , Humanos , Ácido Hialurônico/química , Nanopartículas/ultraestrutura , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier
15.
J Biomed Nanotechnol ; 15(4): 830-838, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30841975

RESUMO

Purpose: The aim of this study was to synthesize bevacizumab-loaded nanoparticles and evaluate their effects on the treatment of posterior segment diseases via subtenon injections. Methods: Bevacizumab-loaded chitosan nanoparticles (BLCNs) were synthesized by the ionic gelation method, and their physicochemical characteristics and in vitro release profile were studied. The BLCNs were characterized using atomic force microscopy (AFM), FTIR spectroscopy, dynamic light scattering, and scanning electron microscopy. The BLCNs were delivered into rabbits' eyes via posterior subtenon injections. An immunohistochemical evaluation of the ocular tissues was performed, and the vitreous humor and serum bevacizumab levels were measured by ELISA. Results: Bevacizumab-loaded chitosan nanoparticles with a diameter of 80 to 380 nm were prepared and characterized. In vitro studies showed that after the first 5 days of the experiment, a significant increase in the drug release maintained the desired drug dosage for 3 weeks. Immunohistochemical in vivo studies revealed that there were BLCNs penetrating through the sclera. Furthermore, the intravitreal bevacizumab concentration reached a maximum concentration of 18 µg/ml, and it decreased to 6 µg/ml after only a week. Conclusion: The results revealed that subtenon injection of BLCNs is a promising alternative to intravitreal injections. In addition to the ELISA studies, immunohistochemical experiments confirmed that BLCNs enable transscleral bevacizumab penetration, and BLCN usage may provide the required bevacizumab levels for the treatment of posterior segment diseases.


Assuntos
Nanopartículas , Animais , Bevacizumab , Quitosana , Coelhos , Esclera , Corpo Vítreo
16.
J Colloid Interface Sci ; 510: 318-326, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28957748

RESUMO

In this work, we developed a disposable amperometric sandwich-type immunoassay to detect prostate specific antigen (PSA). A self-assembled peptide nanotube (PNT), gold nanoparticle (AuNP) and polyaniline (PANI) composite (PANI/AuNP-PNT) were used to modify a pencil graphite electrode (PGE). Anti-PSA (Ab1) was immobilized on the modified electrode (PANI/AuNP-PNT/PGE) to capture PSA. Horseradish peroxidase (HRP) labeled anti-PSA (HRP-Ab2) was used as a tracer antibody. The modified electrodes were characterized with scanning electron microscopy (SEM), thermogravimetric analysis (TGA), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). PSA concentration in phosphate buffer (pH=7.4) was determined with electro-catalytic reduction of H2O2 on the modified working electrode by using the chronoamperometric method. Limit of detection was found out to be 0.68ng/mL in a linear range of 1-100ng/mL with a high regression (R2=0.990). To show the practicality of the modified biosensor in real matrixes, it was successfully applied for the detection of PSA in blood serum samples. The proposed method was also compared with enzyme-linked immunosorbent assay (ELISA) and compatible results were obtained. The developed immunoassay exhibited good reproducibility together with high stability and provides an efficient approach to detect PSA cost-effectively compared to traditional methods.


Assuntos
Compostos de Anilina/química , Ouro/química , Grafite/química , Imunoensaio/métodos , Nanopartículas Metálicas/química , Nanotubos de Peptídeos/química , Antígeno Prostático Específico/sangue , Técnicas Biossensoriais , Técnicas Eletroquímicas , Eletrodos , Ensaio de Imunoadsorção Enzimática , Peroxidase do Rábano Silvestre/química , Humanos , Peróxido de Hidrogênio/química , Limite de Detecção , Masculino , Tamanho da Partícula , Reprodutibilidade dos Testes , Propriedades de Superfície
17.
Anal Sci ; 34(7): 789-794, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29998960

RESUMO

Early diagnosis of cancer is the most important factor that increases the success of treatment. Therefore, the development of new diagnostic tools is a necessity. In this study, a new electrode surface was developed via modification of a disposable titanium electrode with anodic oxidation and coating of gold nanoparticle and chitosan. Titanium electrodes were anodized by several anodization parameters to obtain a nanoporous surface and characterized by scanning electron microscopy. Electrodes anodized in optimum conditions were modified with gold nanoparticles and chitosan for enhancing conductivity and functionalizing the surface of electrode, respectively. To detect prostate specific antigen (PSA), anti-PSA was bound onto the functional electrode surface. Modified electrodes were characterized with scanning electron microscopy and cyclic voltammetry and used for chronoamperometric detection of PSA. Limit of detection (LOD) of the designed electrode was found to be 7.8 ng mL-1 for PSA in a linear range of 0 - 100 ng mL-1.


Assuntos
Técnicas Eletroquímicas , Imunoensaio , Nanotubos/química , Antígeno Prostático Específico/análise , Titânio/química , Eletrodos , Humanos , Masculino , Tamanho da Partícula , Porosidade , Propriedades de Superfície
18.
Biosens Bioelectron ; 104: 50-57, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29306761

RESUMO

A novel diphenylalaninamid (FFA) based peptide nanoparticles (PNPs) modified pencil graphite electrodes (PGEs) for construction of electrochemical cytosensor was demonstrated for the first time in this study. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images revealed the spherical nanostructure of the synthesized FFA based PNPs while attenuated total reflectance-fourier transform infrared (ATR-FTIR) spectra provided information about the structure and conformation of proteins in their structure. Self-assembly of PNPs on PGE surface and adhesion of DLD-1 cancer cells on this surface was also characterized by electrochemical measurements. PNP/PGEs acted as a sensitive platform for simple and rapid quantification of low concentration of DLD-1 cancer cells in early diagnosis using the electrochemical impedance method (EIS). The offered cytosensor demonstrated outstanding performance for the detection of DLD-1 cells by the EIS method. The impedance of electronic transduction was associated with the amount of the immobilized cells ranging from 2 × 102 to 2.0 × 105 cellsmL-1 with a limit of detection of 100 cellsmL-1. The efficient performance of the cytosensor was attributed to the well-defined nanostructure and biocompability of PNPs on the substrate.


Assuntos
Técnicas Biossensoriais , Separação Celular , Nanopartículas Metálicas/química , Neoplasias/diagnóstico , Peptídeos/química , Linhagem Celular Tumoral , Humanos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Neoplasias/patologia , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Artif Cells Nanomed Biotechnol ; 45(6): 1-14, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27396677

RESUMO

Antimicrobial mixed dressings have traditionally been used to minimize bacterial infection of burns and other wounds. This study presents the advancement of biocompatible chitosan/silk sericin (CHT/SS) scaffolds combined with lauric acid (LA) and zinc oxide nanoparticles (nZnO) for the successful wound dressing applications. Antibacterial assay results showed that the diameters of the inhibition zone increased from 2 ± 0.4 to 7 ± 0.1 mm for Escherichia coli, as well as from 2.5 ± 0.2 to 6 ± 0.4 mm for Staphylococcus aureus while CHTS/SS/100nZnO compared to CHT/SS/0.01LA. The results not only showed excellent inhibition against Gram-positive and Gram-negative bacterial growth but also revealed improved proliferation and extended viability for HaCaT cells.


Assuntos
Bandagens , Quitosana , Nanopartículas , Sericinas , Alicerces Teciduais/química , Óxido de Zinco , Queimaduras/terapia , Quitosana/química , Quitosana/farmacologia , Ácidos Láuricos/química , Ácidos Láuricos/farmacologia , Nanopartículas/química , Nanopartículas/uso terapêutico , Porosidade , Sericinas/química , Sericinas/farmacologia , Staphylococcus aureus/crescimento & desenvolvimento , Óxido de Zinco/química , Óxido de Zinco/farmacologia
20.
Artif Cells Nanomed Biotechnol ; 45(2): 193-203, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27087191

RESUMO

In this study, human serum albumin (HSA) was used as a protein-based material and poly (3-hydroxybutyrate) (PHB)-carboxymethyl chitosan (CMCh) as a polysaccharide-based material for the production of nanoparticles to be used as nanocarriers in cancer therapy. HSA and PHB-CMCh nanoparticles were prepared and characterized with a Zeta Sizer, Fourier transform infrared spectroscopy, scanning electron microscopy, and atomic force microscope. The effects of the pH value of the suspending medium and the amounts of crosslinker and polymer concentration on nanoparticle size and size distribution were investigated. The anticancer-agent etoposide was used as a model drug and encapsulated in nanoparticles to obtain drug release profiles. The entrapment efficiency of HSA nanoparticles was found to be greater than that of PHB-CMCh nanoparticles. To achieve "active" targeting of cancer cells, the nanoparticles were modified with concanavalin A. In the final step of the study, the interaction of nanoparticles with cancer cells was investigated in cytotoxicity and cellular uptake studies.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Quitosana , Sistemas de Liberação de Medicamentos/métodos , Hidroxibutiratos , Nanopartículas/química , Poliésteres , Albumina Sérica , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Quitosana/química , Quitosana/farmacologia , Feminino , Humanos , Hidroxibutiratos/química , Hidroxibutiratos/farmacologia , Células MCF-7 , Nanopartículas/ultraestrutura , Poliésteres/química , Poliésteres/farmacologia , Proibitinas , Albumina Sérica/química , Albumina Sérica/farmacologia
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