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1.
Int J Biol Macromol ; 266(Pt 2): 131337, 2024 May.
Article in English | MEDLINE | ID: mdl-38574911

ABSTRACT

Utilization of injectable hydrogels stands as a paradigm of minimally invasive intervention in the context of intervertebral disc degeneration treatment. Restoration of nucleus pulposus (NP) function exerts a profound influence in alleviating back pain. This study introduces an innovative class of injectable shear-thinning hydrogels, founded on quaternized chitosan (QCS), gelatin (GEL), and laponite (LAP) with the capacity for sustained release of the anti-inflammatory drug, celecoxib (CLX). First, synthesis of Magnesium-Aluminum-Layered double hydroxide (LDH) was achieved through a co-precipitation methodology, as a carrier for celecoxib and a source of Mg ions. Intercalation of celecoxib within LDH layers (LDH-CLX) was verified through a battery of analytical techniques, including FTIR, XRD, SEM, EDAX, TGA and UV-visible spectroscopy confirmed a drug loading efficiency of 39.22 ± 0.09 % within LDH. Then, LDH-CLX was loaded in the optimal GEL-QCS-LAP hydrogel under physiological conditions. Release behavior (15 days profile), mechanical properties, swelling ratio, and degradation rate of the resulting composite were evaluated. A G* of 15-47 kPa was recorded for the hydrogel at 22-40 °C, indicating gel stability in this temperature range. Self-healing properties and injectability of the composite were proved by rheological measurements. Also, ex vivo injection into intervertebral disc of sheep, evidenced in situ forming and NP cavity filling behavior of the hydrogel. Support of GEL-QCS-LAP/LDH-CLX (containing mg2+ ions) for viability and proliferation (from ~94 % on day 1 to ~134 % on day 7) of NP cells proved using MTT assay, DAPI and Live/Dead assays. The hydrogel could significantly upregulate secretion of glycosaminoglycan (GAG, from 4.68 ± 0.1 to 27.54 ± 1.0 µg/ml), when LHD-CLX3% was loaded. We conclude that presence of mg2+ ion and celecoxib in the hydrogel can lead to creation of a suitable environment that encourages GAG secretion. In conclusion, the formulated hydrogel holds promise as a minimally invasive candidate for degenerative disc repair.


Subject(s)
Celecoxib , Chitosan , Gelatin , Hydrogels , Silicates , Hydrogels/chemistry , Hydrogels/pharmacology , Celecoxib/pharmacology , Celecoxib/chemistry , Celecoxib/administration & dosage , Chitosan/chemistry , Gelatin/chemistry , Silicates/chemistry , Silicates/pharmacology , Nucleus Pulposus/drug effects , Nucleus Pulposus/metabolism , Animals , Drug Liberation , Drug Carriers/chemistry , Drug Delivery Systems , Injections , Rheology
2.
Int J Biol Macromol ; 235: 123525, 2023 Apr 30.
Article in English | MEDLINE | ID: mdl-36841392

ABSTRACT

Gellan gum (GG) is a biodegradable polysaccharide and forms thermosensitive hydrogels by a helix-mediated mechanism. Unfortunately, the wide use of GG in tissue engineering has been restricted due to its dramatically higher gelation temperature than normal body temperature. Here, we show that partial sulfation of GG affords a cytocompatible body temperature-responsive hydrogel with an interesting thermoreversibility at 42 °C. The partial sulfation of GG was confirmed by FTIR, EDX and elemental analyses. The sulfated GGs (SGGs) had a higher swelling ratio and degradation in PBS compared to the neat GG. Based on the results of rheometry analysis, the SGG with a degree of sulfation of 0.27 (H3 sample) showed a gelation temperature close to the physiological temperature. In addition, the drop in mechanical properties of SGGs was compensated by a further calcium-mediated ionic crosslinking, where Young's modulus of H3 increased from 10.6 ± 1.9 kPa up to 38.4 ± 5.5 kPa. Finally, we showed that the partial sulfation reaction of GG is a simple and mild strategy to modify chemical structure of GG, and to produce a cytocompatible, body temperature-responsive hydrogel compared to other modifying reactions such as oxidation reaction.


Subject(s)
Body Temperature , Hydrogels , Hydrogels/chemistry , Polysaccharides, Bacterial/chemistry , Tissue Engineering/methods
3.
Biomed Mater ; 17(5)2022 08 31.
Article in English | MEDLINE | ID: mdl-35973416

ABSTRACT

Developing an engineered scaffold inspired by structural features of healthy articular cartilage (AC) has attracted much attention. In this study, the design and fabrication of a three-layered fiber/hydrogel scaffold in which each layer replicates the organization of a pertinent layer of AC tissue is aimed. To this end, electrospun poly-L-lactic acid (PLLA) nanofibers are prepared and fragmented into nano/micro cylinders via aminolysis. Three-layers of the scaffold, a fibrin coated fibrous layer, a fibrin gel (FG) layer incorporating chopped fibers and a FG embedding cylindrical aligned fibrous mat perpendicular to articulating surface, respectively served as an upper, middle and bottom layers, are prepared. The layers' physicomechanical characteristics are comprehensively evaluated. Results show that optimized electrospinning set up results in the smallest fibers diameter of 367 ± 317 nm and successful aminolysis provides amine-functionalized chopped nanofibers with a mean length of 1.46 ± 0.9 µm. Static mechanical analysis of the layers demonstrates that tensile Young's modulus of the upper layer is 152 ± 17 MPa while compressive moduli of the middle and bottom layers are 9.8 ± 3.8 and 25.3 ± 5.2 KPa, respectively and the compressive modulus of three-layered scaffold is 13.7 ± 2.5 KPa. Assessing mechanical parameters under dynamic loading also shows that adding fibrous part in the composite scaffold layers enhances viscoelastic behavior of FG. Also, incorporation of 0.25% chopped fibers into the fibrin matrix notably enhances the equilibrium water content; however, it increasesin-vitroweigh loss rate from 6% to 10.5% during a seven-day period. Cytocompatibility analysis confirms that all layers possess acceptable cytocompatibility. In a conclusion, the designed three-layered composite structure successfully mimics the physicomechanical as well as microstructural features of AC and could be suggested as a potential scaffold for this tissue regeneration.


Subject(s)
Cartilage, Articular , Nanofibers , Biomimetics , Fibrin , Materials Testing , Nanofibers/chemistry , Polyesters/chemistry , Tissue Engineering/methods , Tissue Scaffolds/chemistry
4.
J Wound Care ; 31(7): 598-611, 2022 Jul 02.
Article in English | MEDLINE | ID: mdl-35797256

ABSTRACT

OBJECTIVE: The present study aims to create Calendula officinalis-loaded nanofibre-based wound dressing materials to enhance the wound healing process. Calendula officinalis is an annual herb native to the Mediterranean region. It is antipyretic, antifungal, antioedema, antidiabetic, anti-inflammatory (wound, oral and pharyngeal mucosa), antispasmodic, treats chronic ocular surface diseases, acts as a stimulant and a diaphoretic. It is also used in the prevention of acute dermatitis, and in the treatment of gastrointestinal ulcers, wounds and burns. METHOD: Electrospinning is an effective method for creating nano- and microfibres for biomedical applications. Calendula officinalis (CA) of various concentrations 5%, 10% and 15%)-loaded polyvinyl alcohol (PVA)/sodium alginate (SAlg) nanofibre mats were successfully produced via blend electrospinning. Nanofibre mats were evaluated using: scanning electron microscopy (SEM); Fourier transform infrared spectroscopy (FTIR) analysis; gel content; water vapour transmission rate (WVTR); swelling ratio; in vitro drug release studies; viability evaluation (cell culture and MTT assay); and an in vivo study using male Wistar rats. Rats were divided into three groups (n=3). In each group, rats were inflicted with five full-thickness wounds on the back and were treated with sterile gauze (control), PVA/SAlg nanofibre dressing (CA-free control), PVA/SAlg/CA5%, PVA/SAlg/CA10%, and PVA/SAlg/CA15% nanofibre dressing. RESULTS: Results showed that the obtained fibres were smooth with no surface aggregates, indicating complete incorporation of Calendula officinalis. The release of Calendula officinalis from loaded PVA/SAlg fibre mats in the first four hours was burst released and then was constant. PVA/SAlg and PVA/SAlg/CA nanofibres were not toxic to L929 mouse fibroblasts and supported cell attachment and proliferation. The results of the in vivo study showed that the PVA/SAlg/CA10% nanofibre dressing had a higher full-thickness wound healing closure rate compared with the control group on days seven, 14 and 21 after treatment. CONCLUSION: The results of this evaluation showed that PVA/SAlg/CA nanofibrous mats could be a candidate as an effective wound dressing; however, the percentage of CA in this compound needs further investigation.


Subject(s)
Calendula , Nanofibers , Alginates , Animals , Bandages , Male , Mice , Nanofibers/chemistry , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Polyvinyl Alcohol , Rats , Rats, Wistar
5.
Mater Sci Eng C Mater Biol Appl ; 126: 112180, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34082980

ABSTRACT

Many research groups have investigated the various kinds of scaffolds to mimic the natural Bruch's membrane (BM) and support the retinal pigmented epithelial cells to form an organized cellular monolayer. While using prosthetic BM is identified as a promising treatment of age-related macular degeneration (AMD), a degenerative and progressive retinal disease, the effects of different signals such as electrical and morphological cues on the retinal pigmented epithelial (RPE) cells are still unknown. In this study, a laminated and conductive hydrogel/fiber composite scaffold by adding conductive polyaniline (PANi) to the scaffold's nanofibrous phase was prepared. This hybrid scaffold offers the closest morphology to the native structure of the human Bruch's membrane by imitating the inner and outer collagenous layer and induces the electrical signal to the scaffold to assess the electrical cue on behaviors of polarized retinal pigmented epithelial cells in the retina. The electrospun nanofibrous phase consisted of gelatin-Polyaniline in different ratios incorporated into the hydrogel precursor, a blend of gelatin and 4-armed PEG. We used a novel dual crosslinking process by incorporating the exposure of gamma irradiation and glutaraldehyde vapor treatment to construct the scaffold's hydrogel phase. The results showed the best composition was the sample which included the 40/60, Polyaniline/gelatin nanofiber sheets ratio because this scaffold revealed a 2.66 ± 0.33 MPa, Young's modulus and 1.84 ± 0.21 S/cm, electrochemical conductivity, which are close to the main features of native Bruch's membrane. In addition, this scaffold showed good biocompatibility by reaching 83.47% cell viability.


Subject(s)
Bruch Membrane , Nanofibers , Gelatin , Humans , Membranes, Artificial , Retina
6.
Biomater Sci ; 9(7): 2679-2695, 2021 Apr 07.
Article in English | MEDLINE | ID: mdl-33605970

ABSTRACT

Nanotechnology has a vital role in vaccine development. Nano-adjuvants, as robust delivery systems, could stimulate immune responses. Using nanoparticles (NPs) in vaccine formulations enhances the target delivery, immunogenicity, and stability of the antigens. Herein, silk fibroin nanoparticles (SFNPs) were used as a nano-adjuvant for delivering recombinant hepatitis B surface antigen (HBsAg). HBsAg was loaded physically and chemically on the surface of SFNPs. The HBsAg-loaded SFNPs had a spherical morphology. The in vitro release studies showed that HBsAg had a continuous and slow release from SFNPs during 56 days. During this time, ∼45.6% and 34.1% HBsAg was released from physical-SFNPs and chemical-SFNPs, respectively. HBsAg-loaded SFNPs were also stable for six months with slight changes in the size, surface charge, and morphology. The results of circular dichroism (CD) and fluorescence spectroscopy indicated that the released HBsAg preserved the native secondary and tertiary structures. The quantitative cellular uptake study also showed that physical-SFNPs were taken up more into J774A.1 macrophage cells than chemical-SFNPs. After 28 and 56 days post-injection, the immunogenicity studies showed that the specific total IgG, IgG1, and IgG2a levels against HBsAg were significantly higher in the physically loaded group than in the chemically loaded group and commercial hepatitis B vaccine. IgG2a levels were detected only in mice immunized with physical-SFNPs. However, the low levels of IL-4 and IFN-γ were produced in all vaccinated groups and differences in mean values were not significant compared with control groups. Results indicated an improvement in the levels of anti-HBsAg IgG in mice immunized with the physical-SFNPs group compared to other groups.


Subject(s)
Fibroins , Nanoparticles , Adjuvants, Immunologic , Animals , Hepatitis B Surface Antigens , Hepatitis B Vaccines , Mice , Mice, Inbred BALB C
7.
J Biomed Mater Res B Appl Biomater ; 108(5): 2276-2293, 2020 07.
Article in English | MEDLINE | ID: mdl-31967388

ABSTRACT

Myocardial infarction occurs because coronary arteries insufficiency is one of the major causes of mortality worldwide. Recent studies have shown that tissue engineering of myocardial tissue to regenerate infarcted tissue or engineering of the coronary artery may help overcome this problem. In the present research, gelatin and single-walled carbon nanotube were firstly administrated to physico-chemically and biologically modulate polyurethane nanofibers. Electrospinning, as versatile and effective technique for production of functional nanoscale fiber, was applied. Incorporation of both gelatin and SWNTs reduced mean diameter of nanofibrous scaffolds from 210 to 140 nm, which influenced on initial cell behavior. Possible interaction between gelatin and SWNTs with polyurethane chains was evaluated using FTIR and DSC techniques. Regarding the incorporation of both gelatin and SWNTs, it was found that hydrophilicity of nanofibrous scaffolds dramatically improved. Scaffold degradation profile was adjusted by incorporation of gelatin. Biomimetic mechanical properties of composite scaffolds like normal blood vessel were developed and SWNTs improved the Young modulus and ultimate strength of scaffolds up to 16.47 ± 0.5 and 23.73 ± 0.5 MPa, respectively. However, addition of gelatin increased elongation at break due to its softening effect. The incorporation of the SWNTs led to significant enhancement of electrical conductivity of the scaffolds. Biological evaluation using SEM and MTT assay demonstrated that nanofibrous surface was covered by confluent and dense layer of both myocardial myoblast and endothelial cells after 7 days of culture, which is crucial for cardiovascular tissue engineering. Results verified that the fabricated scaffolds could be effective for cardiovascular tissue engineering.


Subject(s)
Biocompatible Materials/chemistry , Cardiovascular Diseases/therapy , Gelatin/chemistry , Nanotubes, Carbon/chemistry , Polyurethanes/chemistry , Tissue Scaffolds/chemistry , Blood Vessel Prosthesis Implantation , Cardiovascular Diseases/surgery , Cell Proliferation , Coronary Vessels , Elastic Modulus , Electric Conductivity , Humans , Hydrophobic and Hydrophilic Interactions , Mechanical Tests , Nanofibers/chemistry , Tensile Strength , Tissue Engineering
8.
Eur J Pharm Biopharm ; 146: 133-142, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31698041

ABSTRACT

Doxorubicin is an anti-cancer drug that is important for breast cancer therapy. In this study, the effects of the membrane potential of breast cancer cells (-30 mV) and normal breast epithelial cells (-60 mV) on doxorubicin (DOX) permeability was studied. To achieve this goal, black lipid membranes (BLMs) as a model cell membrane were formed with DPhPC phospholipids in a single aperture of a Teflon sheet by the Montal and Mueller method. The presence of the BLM was characterized by capacitive measurements. The measured specific capacitance of 0.6 µF/cm2 after applying the Montal and Mueller method, confirming the presence of a BLM in the aperture. In addition, the very low current leakage of the BLM (9-24 pA) and ClyA-protein channel insertion in the BLM indicate the compactness, high quality, and thickness of 3-5 nm of the BLM. Afterwards, the permeability of doxorubicin through the BLM was studied at defined cell conditions (37 °C and pH 7.4), as well as cancerous and healthy epithelial-cell membrane potentials (-30 mV and -60 mV, respectively). The results show a slow DOX penetration within the first few hours, which increases rapidly with time. The initial slow penetration can be attributed to an electrostatic interaction between doxorubicin and DPhPC molecules in the model cell membrane. Furthermore, a MTT assay on MCF-10A and MCF-7 under different concentrations of doxorubicin confirmed that the cancerous MCF-7 cell line is more resistant to doxorubicin in comparison with the non-cancerous MCF-10A. Such studies highlight important strategies for designing and tuning the interaction efficacy of novel pharmaceuticals at molecular level.


Subject(s)
Antineoplastic Agents/pharmacokinetics , Breast Neoplasms/drug therapy , Cell Membrane Permeability/physiology , Doxorubicin/pharmacokinetics , Membrane Potentials , Antineoplastic Agents/administration & dosage , Apoptosis/drug effects , Breast Neoplasms/pathology , Dose-Response Relationship, Drug , Doxorubicin/administration & dosage , Drug Resistance, Neoplasm , Epithelial Cells/cytology , Epithelial Cells/metabolism , Female , Humans , Lipid Bilayers/metabolism , MCF-7 Cells , Phospholipids/metabolism
10.
Iran Endod J ; 13(3): 299-304, 2018.
Article in English | MEDLINE | ID: mdl-30083197

ABSTRACT

INTRODUCTION: The objective of this study was to evaluate the physical properties, cytotoxicity and sealing ability of HealApex _a new premixed calcium-silicate-phosphate-based biosealer_ in comparison with AH-26. METHODS AND MATERIALS: Setting time, working time, film thickness, flow and radiopacity evaluation were performed according to ISO 6876 specification. L929 fibroblasts were incubated with the extracts of sealers and cytotoxicity was then evaluated using MTT assay. Thirty intact extracted human premolars were instrumented using step-back technique. The specimens were obturated with gutta-percha and experimental sealers employing lateral condensation technique. Sealing ability of sealers was investigated for up to one month using fluid filtration method. Data were statistically analyzed by t-test and ANOVA. RESULTS: Physical properties of both sealers conformed to ISO specification. AH-26 exhibited significantly higher flow, higher radiopacity and lower film thickness; whereas HealApex showed lower setting time (P<0.05). HealApex represented high cell viability (P<0.05); however, AH-26 demonstrated significantly lower cell viability compared with the negative control group (P<0.05). There was no significant difference in microleakage between the sealers after 1 and 7 days; however, after 30 days, HealApex displayed better sealing ability (P<0.05). CONCLUSIONS: In this in vitro study, HealApex revealed acceptable physical properties, biocompatibility and good sealing ability as an endodontic sealer. Obtained results showed the new sealer had acceptable physical properties and good biocompatibility. In short term, the sealing ability of HealApex was comparable with AH-26 whilst in long term, HealApex's sealing ability was better than the epoxy resin-based sealer.

11.
Iran J Pharm Res ; 16(2): 413-422, 2017.
Article in English | MEDLINE | ID: mdl-28979296

ABSTRACT

Glaucoma is a common progressive eye disorder and the treatment strategies will benefit from nanoparticulate delivery systems with high drug loading and sustained delivery of intraocular pressure lowering agents. Niosomes have been reported as a novel approach to improve drug low corneal penetration and bioavailability characteristics. Along with this, poor entrapment efficiency of hydrophilic drug in niosomal formulation remains as a major formulation challenge. Taking this perspective into consideration, dorzolamide niosomes were prepared employing two different loading methodologies (passive and remote loading methods) and the effects of various formulation variables (lipid to drug ratio, cholesterol percentage, drug concentration, freeze/thaw cycles, TPGS content, and external and internal buffer molarity and pH) on encapsulation efficiency were assessed. Encapsulation of dorzolamide within niosomes increased remarkably by the incorporation of higher cholesterol percentage as well as increasing the total lipid concentration. Remote loading method showed higher efficacy for drug entrapment compared to passive loading technique. Incorporation of TPGS in bilayer led to decrease in EE; however, retarded drug release rate. Scanning electron microscopy (SEM) studies confirmed homogeneous particle distribution, and spherical shape with smooth surface. In conclusion, the highest encapsulation can be obtained using phosphate gradient method and 50% cholesterol in Span 60 niosomal formulation.

12.
Mater Sci Eng C Mater Biol Appl ; 76: 934-943, 2017 Jul 01.
Article in English | MEDLINE | ID: mdl-28482609

ABSTRACT

Parkinson's disease (PD) is a progressive neurodegenerative disorder that characterized by destruction of substantia nigrostriatal pathway due to the loss of dopaminergic (DA) neurons. Regardless of substantial efforts for treatment of PD in recent years, an effective therapeutic strategy is still missing. In a multidisciplinary approach, bone marrow derived mesenchymal stem cells (BMSCs) are genetically engineered to overexpress neurotrophin-3 (nt-3 gene) that protect central nervous system tissues and stimulates neuronal-like differentiation of BMSCs. Poly(lactic-co-glycolic acid) (PLGA) microcarriers are designed as an injectable scaffold and synthesized via double emulsion method. The surface of PLGA microcarriers are functionalized by collagen as a bioadhesive agent for improved cell attachment. The results demonstrate effective overexpression of NT-3. The expression of tyrosine hydroxylase (TH) in transfected BMSCs reveal that NT-3 promotes the intracellular signaling pathway of DA neuron differentiation. It is also shown that transfected BMSCs are successfully attached to the surface of microcarriers. The presence of dopamine in peripheral media of cell/microcarrier complex reveals that BMSCs are successfully differentiated into dopaminergic neuron. Our approach that sustains presence of growth factor can be suggested as a novel complementary therapeutic strategy for treatment of Parkinson disease.


Subject(s)
Mesenchymal Stem Cells , Brain , Cell Differentiation , Humans , Lactic Acid , Parkinson Disease , Polyglycolic Acid , Polylactic Acid-Polyglycolic Acid Copolymer , Tissue Engineering
13.
Int J Artif Organs ; 39(6): 294-9, 2016 Aug 19.
Article in English | MEDLINE | ID: mdl-27515859

ABSTRACT

INTRODUCTION: In recent years, the extremely low frequency electromagnetic field (ELF-EMF) has attracted a great deal of scientific interest. The ELF-EMF signal is able to control ion transport across ion channels and therefore induce cell differentiation. AIM: The purpose of this study was to investigate the effect of ELF-EMF (50 Hz, 1 mT) on MAP2 and Nestin gene expression of dermal papilla mesenchymal cells (DPCs). METHODS: In order to examine the effect of chemical and electromagnetic factors on gene expression, 4 experimental groups, namely chemical (cell exposure to chemical signals), EMF (exposing cells to ELF-EMF), chemical-EMF (subjecting cells to chemical signals and ELF-EMF) and control (with no treatment) groups, were prepared, treated for 5 days, and studied. To assess the effect of extended test time on the expression of neural differentiation markers (Nestin and MAP2), an EMF group was prepared and treated for a period of 14 consecutive days. The beneficial role of EMF in inducing neural differentiation was shown by real-time PCR analysis. RESULTS: The higher expression of MAP2 after 14 days compared to that after 5 days and decrease of cell proliferation on days 5 to 20 were indicative of the positive effect of extending treatment time on neural differentiation by evaluation of gene expression in EMF group.


Subject(s)
Electromagnetic Fields , Gene Expression Regulation/radiation effects , Hair Follicle/radiation effects , Microtubule-Associated Proteins/genetics , Nestin/genetics , Adult , Cell Differentiation/radiation effects , Cell Proliferation/radiation effects , Hair Follicle/metabolism , Humans , Male , Mesenchymal Stem Cells/metabolism , Mesenchymal Stem Cells/radiation effects , Microtubule-Associated Proteins/metabolism , Nestin/metabolism , Real-Time Polymerase Chain Reaction
14.
Mater Sci Eng C Mater Biol Appl ; 62: 544-52, 2016 May.
Article in English | MEDLINE | ID: mdl-26952457

ABSTRACT

This study has investigated the possibility of using fluorescent dendronized magnetic nanoparticles (FDMNPs) for potential applications in drug delivery and imaging. FDMNPs were first synthesized, characterized and then the effect of Polyamidoamine (PAMAM) dendrimer functionalization and fluorescein isothiocyanate (FITC) conjugation on biocompatibility of superparamagnetic iron oxide nanoparticles (SPIONs) was evaluated. The nanostructures' cytotoxicity tests were performed at different concentrations from 10 to 500 µg/mL using MCF-7 and L929 cell lines. IC50 in MTT assay were 139.22 and 201.88 µg/mL for DMNP incubated L929 and MCF-7 cell lines respectively, whereas the cell viability for FDMNPs did not decrease to 50%. The results showed that FITC conjugation diminishes the toxicity of dendronized magnetic nanoparticles (DMNPs) mainly due to the reduction of surface charge. DMNP appears to be cytotoxic at the concentration levels being used for both cell lines. On the contrary, FDMNPs showed more biocompatibility and cell viability of MCF-7 and L929 cell lines at all concentrations. The fluorescence microscopy of FDMNPs incubated with MCF-7 cells showed a successful localization of cells indicating their ability for applications such as a magnetic fluorescent probe in cell studies and imaging purposes. T2 relaxivity measurements demonstrated the applicability of the synthesized nanostructures as the contrast agents in tissue differential assessment by altering their relaxation times. In our case, the r2 relaxivity of FDMNPs was measured as 103.67 mM(-1)S(-1).


Subject(s)
Dendrimers/chemistry , Dextrans/chemistry , Fluorescein/chemistry , Magnetite Nanoparticles/chemistry , Biocompatible Materials/chemistry , Biocompatible Materials/toxicity , Cell Line, Tumor , Cell Survival/drug effects , Contrast Media/chemistry , Contrast Media/toxicity , Dendrimers/toxicity , Humans , MCF-7 Cells , Magnetic Resonance Imaging , Magnetite Nanoparticles/toxicity , Microscopy, Fluorescence , Neoplasms/diagnostic imaging , Particle Size , Spectroscopy, Fourier Transform Infrared
15.
Curr Drug Deliv ; 13(1): 57-64, 2016.
Article in English | MEDLINE | ID: mdl-26234551

ABSTRACT

In this study drug (paclitaxel)-loaded nanoparticles of poly hydroxybutyrate-polyethylene glycol-folic acid (PHB-PEG-FOL) were prepared by using an oil-in-water (O/W) emulsion-solvent evaporation method. The functionalization and conjugation steps in the chemical synthesis were confirmed using Fourier transform infrared (FTIR) and nuclear magnetic resonance tests ((1)H NMR). Morphology of nanoparticles was evaluated by scanning electron microscopy (SEM). Nanoparticles were characterized by particle size analyzer. Between two samples containing drug, the lower doses showed more homogeneous distribution, and the lowest aggregation. The drug release profiles showed a two-phase release including initial rapid release and a continuous release. MG63 cells were used to evaluate cytotoxicity. The cytotoxicity of PHB-PEG-FOL nanoparticles with drug against cancer cells was much higher and longer than free drug sample. These nanoparticles were successfully synthesized as a novel system for targeted drug delivery against cancer cells.


Subject(s)
Folic Acid/chemistry , Hydroxybutyrates/chemistry , Nanoparticles/chemistry , Paclitaxel/chemistry , Paclitaxel/pharmacology , Polyethylene Glycols/chemistry , Cell Line, Tumor , Cell Survival/drug effects , Drug Carriers/chemistry , Drug Delivery Systems/methods , Emulsions/chemistry , Emulsions/pharmacology , Humans , Particle Size , Polymers/chemistry , Prohibitins
16.
Nanomedicine (Lond) ; 10(23): 3431-49, 2015.
Article in English | MEDLINE | ID: mdl-26607456

ABSTRACT

AIMS: Here we report a one-step approach for reproducible synthesis of finely tuned targeting multifunctional hybrid nanoparticles (HNPs). MATERIALS & METHODS: A microfluidic-assisted method was employed for controlled nanoprecipitation of bisphosphonate-conjugated poly(D,L-lactide-co-glycolide) chains, while coencapsulating superparamagnetic iron oxide nanoparticles and the anticancer drug Paclitaxel. RESULTS: Smaller and more compact HNPs with narrower size distribution and higher drug loading were obtained at microfluidic rapid mixing regimen compared with the conventional bulk method. The HNPs were shown to have a strong affinity for hydroxyapatite, as demonstrated in vitro bone-binding assay, which was further supported by molecular dynamics simulation results. In vivo proof of concept study verified the prolonged circulation of targeted microfluidic HNPs. Biodistribution as well as noninvasive bioimaging experiments showed high tumor localization and suppression of targeted HNPs to the bone metastatic tumor. CONCLUSION: The hybrid bone-targeting nanoparticles with adjustable characteristics can be considered as promising nanoplatforms for various theragnostic applications.


Subject(s)
Diphosphonates/chemistry , Microfluidics/methods , Nanoparticles/chemistry
17.
Acta Inform Med ; 23(2): 97-101, 2015 Apr.
Article in English | MEDLINE | ID: mdl-26005275

ABSTRACT

INTRODUCTION: The useful capabilities of information and communication technologies for improving health services are becoming widely known. However many of the managers and policymakers of health systems are not yet familiar with these technologies, their dimensions and applications and the advantages of these new technologies for creating added value in health systems. Therefore the goal of this study is to determine the awareness and attitude of employees working for Deputy of Health of Isfahan University of Medical Science regarding telemedicine and its advantages. METHOD: This study uses a descriptive - analytical method with sectional information gathering. The investigated population consisted of all managers and experts employed by Deputy of health of Isfahan University of Medical Science. The sample size was determined based on inclusion criteria to be 60 people. The data gathering tool was a questionnaire designed by the researcher in order to determine the awareness and attitude of the subjects. In order to determine the validity and reliability of the questionnaire content validity method and Cronbach's alpha were used. The information was analyzed using descriptive (frequency, average) and analytical (Spearman correlation test and independent t-test) statistics with the help of SPSS19 software. FINDINGS: Research findings showed that the awareness and attitude of managers and experts toward telemedicine was mediocre. Spearman correlation test showed that there is a correlation between the educational degree and awareness of the subject, however the correlation coefficient was lower than 0.5 which shows a weak correlation (0.451). On the other hand, the calculated P-value of 0.008 showed that there is a meaningful relation between the education and awareness of managers regarding telemedicine. CONCLUSION: Due to importance of awareness and attitude in acceptance of new technologies, one can say that currently there is not enough readiness for planning and implementation of telemedicine projects in the Deputy of health. Therefore changes in the organizational culture, organizational structures and infrastructure, current plans and educating the employees in order to improve their awareness and attitude is of great importance.

18.
Colloids Surf B Biointerfaces ; 122: 115-125, 2014 Oct 01.
Article in English | MEDLINE | ID: mdl-25033431

ABSTRACT

For gene and drug delivery applications, carbon nanotubes (CNTs) have to be functionalized in order to become compatible with aqueous media and bind with genetic materials. In this study, combination of polyethyleneimine (PEI) grafted multi-walled carbon nanotubes (PEI-g-MWCNTs) and chitosan substrate is used as an efficient gene delivery system for transfection of hard-to-transfect bone marrow mesenchymal stem cells (BMSCs) with enhanced green fluorescent protein (EGFP) gene. Fourier transform infrared (FT-IR) spectra, dynamic light scattering (DLS) analysis and zeta potential measurements are used to characterize binding of PEI, particle size distribution and colloidal stability of the functionalized CNTs, respectively. DNA binding affinity, cellular uptake, transfection efficiency and possible cytotoxicity are also tested by agarose gel electrophoresis, flow cytometry, cytochemisty and MTT assay. The results demonstrate that cytotoxic effect of PEI-g-MWCNTs is negligible under optimal transfection condition. In consistency with high cellular uptake (>82%), PEI-g-MWCNTs give higher delivery of EGFP into the BMSCs which results in a more sustained expression of the model gene (EGFP) in short-term culture. These results suggest that PEI-g-MWCNTs in corporation with chitosan substrates would be a promising delivery system for BMSCs, a cell type with relevancy in the regenerative medicine and clinical applications.


Subject(s)
Mesenchymal Stem Cells/cytology , Nanotubes, Carbon , Polyethyleneimine/chemistry , Transfection , Animals , Electrophoresis, Agar Gel , HEK293 Cells , Humans , Male , Rats , Rats, Wistar
19.
Acta Inform Med ; 22(5): 320-4, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25568581

ABSTRACT

INTRODUCTION: Awareness of Outlook, objectives, benefits and impact of telemedicine technology that can promote services quality, reduce costs, increase access to Specialized and subspecialty services, and immediately guide the health system subconsciously to the introduction greater use of technology. Therefore, the aim of this study was to determine the strengths, weaknesses, opportunities and threats in the telemedicine strategic planning from the managers and experts perspective in the health department, Isfahan University of Medical Sciences, in order to take a step towards facilitating strategic planning and approaching the equity aim in health in the province. METHOD: This is a descriptive-analytical study, that data collection was done cross-sectional. The study population was composed of all managers and certified experts at the health department in Isfahan university of Medical Sciences. The sample size was 60 patients according to inclusion criteria. Information was collected by interview method. Researcher attempted to use the structured and specific questionnaire Then were investigated the viewpoints of experts and managers about determinative factors (strengths, weaknesses, opportunities and threats) in the strategic planning telemedicine. Data were analyzed using descriptive statistics (frequency, mean) and software SPSS 19. RESULTS: Data analysis showed that change management (100%) and continuity of supply of credit (79/3%) were weakness point within the organization and strengths of the program were, identity and health telemedicine programs (100%), goals and aspirations of the current directors of the organization and its compliance with the goals of telemedicine (100%), human resources interested using computers in daily activities in peripheral levels (93/1%). Also organization in the field of IT professionals, had opportunities, and repayment specialist's rights by insurance organizations is a threat for it. CONCLUSIONS: According to the strengths, weaknesses, opportunities and threats points determined by managers and experts, and compare it with success and failure factors, which are defined by different researchers, it seems will be fail to implement of telemedicine in the province at present. But according to the strengths identified by managers and experts, there are a lot of potential for telemedicine in the province, and may be used, in relation to telemedicine projects, with a 3 or 5 year strategic plan, and taking steps to get closer to the equity aim in health.

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