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Remarkable resistance of bacterial biofilms to high doses of antimicrobials and antibiotics is one of their main challenges. Encapsulation of proteolytic enzymes is one of the suggested strategies to tackle this problem. In this regard, the antibacterial and anti-biofilm activity of biocompatible hyaluronic acid- Lysine nanogels containing serratiopeptidase (SRP-loaded HA-Lys nanogel) was assessed against P. aeruginosa and S. aureus strains. SRP-loaded HA-Lys nanogel was prepared using dropping method and optimized by Box-Behnken experimental design. These formulations were studied for physical characterization, release profile, stability, bioactivity, and anti-biofilm effects. The particle size, polydispersity index (PDI), and surface charge were measured by Zetasizer Nano ZS. The average particle size and zeta potential of the optimum sample were 156 nm and -14.1 mV, respectively. SRP release showed an initial burst followed by sustained release and the highest release was around 77%. Enzyme biological activity data revealed the higher efficiency of free SRP compared to SRP-loaded HA-Lys nanogel. The time-kill assay showed that both forms of SRP-loaded HA-Lys nanogel and blank HA-Lys nanogel showed significant antimicrobial activity against examined bacteria in comparison to the free enzyme. The obtained results demonstrated improved anti-biofilm efficacy and down regulation of tested biofilm genes for both SRP-loaded HA-Lys nanogel 100% and blank HA-Lys nanogel 100% compared to SRP 100%.
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Ácido Hialurónico , Lisina , Polietilenglicoles , Polietileneimina , Nanogeles/química , Ácido Hialurónico/química , Lisina/farmacología , Staphylococcus aureus/fisiología , Péptido Hidrolasas/farmacología , Antibacterianos/farmacología , BiopelículasRESUMEN
Today, enzymatic treatment is a progressive field in combating biofilm producing pathogens. In this regard, serratiopeptidase, a medicinally important metalloprotease, has been recently highlighted as an enzyme with proved anti-biofilm activity. In the present study, in order to increase the long-lasting effects of the enzyme, serratiopeptidase and the novel engineered forms with enhanced anti-biofilm activity were immobilized on the surface of cellulose nanofibers (CNFs) as a natural polymer with eminent properties. For this, recombinant serratiopeptidases including the native and previously designed enzymes were produced, purified and conjugated to the CNF by chemical and physical methods. Immobilization was confirmed using different scanning and microscopic methods. The enzyme activity was assessed using casein hydrolysis test. Enzyme release analysis was performed using dialysis tube method. Anti-biofilm activity of free and immobilized enzymes has been examined on Staphylococcus aureus and Pseudomonas aeruginosa strains. Finally, cytotoxicity of enzyme-conjugated CNFs was performed by MTT assay. The casein hydrolysis results confirmed fixation of all recombinant enzymes on CNFs by chemical method; however, inadequate fixation of these enzymes was found using cold atmospheric plasma (CAP). The AFM, FTIR, and SEM analysis confirmed appropriate conjugation of enzymes on the surface of CNFs. Immobilization of enzymes on CNFs improved the anti-biofilm activity of serratiopeptidase enzymes. Interestingly, the novel engineered serratiopeptidase (T344 [8-339ss]) exhibited the highest anti-biofilm activity in both conjugated and non-conjugated forms. In conclusion, incorporation of serratiopeptidases into CNFs improves their anti-biofilm activities without baring any cytotoxicity. KEY POINTS: ⢠Enzymes were successfully immobilized on cellulose nanofibers using chemical method. ⢠Immobilization of enzymes on CNFs improved their anti-biofilm activity. ⢠T344 [8-339ss] exhibited the highest anti-biofilm activity in both conjugated and non-conjugated forms.
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Celulosa , Nanofibras , Celulosa/química , Nanofibras/química , Caseínas , BiopelículasRESUMEN
This study aimed to present a novel three-dimensional nanocomposite scaffold using poly-ε-caprolactone (PCL), containing transforming growth factor-beta 1 (TGF-ß1)-loaded chitosan-dextran nanoparticles and poly-l-lactic acid (PLLA), to make use of nanofibers and nanoparticles simultaneously. The electrospinning method fabricated a bead-free semi-aligned nanofiber composed of PLLA, PCL, and chitosan-dextran nanoparticles containing TGF-ß1. A biomimetic scaffold was constructed with the desired mechanical properties, high hydrophilicity, and high porosity. Transmission electron microscopy findings showed a linear arrangement of nanoparticles along the core of fibers. Based on the results, burst release was not observed. The maximum release was achieved within 4 days, and sustained release was up to 21 days. The qRT-PCR results indicated an increase in the expression of aggrecan and collagen type Ι genes compared to the tissue culture polystyrene group. The results indicated the importance of topography and the sustained release of TGF-ß1 from bifunctional scaffolds in directing the stem cell fate in cartilage tissue engineering.
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Quitosano , Nanofibras , Nanopartículas , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Nanofibras/química , Factor de Crecimiento Transformador beta1 , Preparaciones de Acción Retardada , Quitosano/química , Dextranos , Poliésteres/química , Cartílago , Nanopartículas/químicaRESUMEN
BACKGROUND: Interleukin-1 receptor accessory protein (IL-1RAP) is one of the most promising therapeutic targets proposed for myeloid leukemia. Antibodies (Abs) specific to IL-1RAP could be valuable tools for targeted therapy of this lethal malignancy. This study is about the preparation of a difficult-to-produce single-chain variable fragment (scFv) construct against the membrane-bound isoform of human IL-1RAP using Escherichia coli (E. coli). METHODS: Different approaches were examined for refolding and characterization of the scFv. Binding activities of antibody fragments were comparatively evaluated using cell-based enzyme-linked immunosorbent assay (ELISA). Homogeneity and secondary structure of selected scFv preparation were analyzed using analytical size exclusion chromatography (SEC) and circular dichroism (CD) spectroscopy, respectively. The activity of the selected preparation was evaluated after long-term storage, repeated freeze-thaw cycles, or following incubation with normal and leukemic serum. RESULTS: Strategies for soluble expression of the scFv failed. Even with the help of Trx, ≥ 98% of proteins were expressed as inclusion bodies (IBs). Among three different refolding methods, the highest recovery rate was obtained from the dilution method (11.2%). Trx-tag substantially enhanced the expression level (18%, considering the molecular weight (MW) differences), recovery rate (Ë1.6-fold), and binding activity (Ë2.6-fold increase in absorbance450nm). The produced scFv exhibited expected secondary structure as well as acceptable bio-functionality, homogeneity, and stability. CONCLUSION: We were able to produce 21 mg/L culture functional and stable anti-IL-1RAP scFv via recovering IBs by pulse dilution procedure. The produced scFv as a useful targeting agent could be used in scheming new therapeutics or diagnostics for myeloid malignancies.
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Leucemia Mieloide , Anticuerpos de Cadena Única , Humanos , Ensayo de Inmunoadsorción Enzimática , Escherichia coli/metabolismo , Proteína Accesoria del Receptor de Interleucina-1/metabolismo , Anticuerpos de Cadena Única/metabolismo , Cuerpos de InclusiónRESUMEN
A PEGylated niosomal formulation of cyclophosphamide (Nio-Cyclo-PEG) was prepared using a central composite design and characterized in terms of drug loading, size distribution, and average size. The stability of formulations was also studied at different conditions. In vitro cytotoxicity of drug delivery formulations was assessed on gastric cancer cells using MTT assay. The mechanism of cytotoxicity was studied at the transcriptional level by real-time PCR on Caspase3, Caspase9, CyclinD, CyclinE, MMP-2, and MMP-9 genes, while apoptosis was investigated with flow cytometry. The anti-metastatic property was evaluated using the scratch method. Propidium iodide staining was used to study the cell cycle. The results indicated that the as-designed nanocarrier exhibited a controlled drug release pattern with improved nanoparticle stability. It was found that the living cancer cells treated with Nio-Cyclo-PEG showed a significant decrease in number when compared with the niosomal carrier without PEG (Nio-Cyclo) and free drug (Cyclo). Moreover, the drug-loaded nanocarrier induced planned death (apoptosis) in the cancer cells through the regulation of Caspase3, Caspase9, CyclinD, CyclinE, MMP-9, and MMP-2 gene expression, indicating that the Nio-Cyclo-PEG formulation could significantly inhibit the cell cycle at the sub G1 phase as well as prevent the migration of cancer cells. In conclusion, Nio-Cyclo-PEG as developed in this study could serve as an active-targeting drug delivery nanocarriers for gastric cancer therapy with high efficacy and minimal side effects on healthy tissues/cells.
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Nanopartículas , Neoplasias Gástricas , Ciclofosfamida , Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Humanos , Concentración de Iones de Hidrógeno , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 9 de la Matriz , Polietilenglicoles , Neoplasias Gástricas/tratamiento farmacológicoRESUMEN
The majority of monogenic liver diseases are autosomal recessive disorders, with few being sex-related or co-dominant. Although orthotopic liver transplantation (LT) is currently the sole therapeutic option for end-stage patients, such an invasive surgical approach is severely restricted by the lack of donors and post-transplant complications, mainly associated with life-long immunosuppressive regimens. Therefore, the last decade has witnessed efforts for innovative cellular or gene-based therapeutic strategies. Gene therapy is a promising approach for treatment of many hereditary disorders, such as monogenic inborn errors. The liver is an organ characterized by unique features, making it an attractive target for in vivo and ex vivo gene transfer. The current genetic approaches for hereditary liver diseases are mediated by viral or non-viral vectors, with promising results generated by gene-editing tools, such as CRISPR-Cas9 technology. Despite massive progress in experimental gene-correction technologies, limitations in validated approaches for monogenic liver disorders have encouraged researchers to refine promising gene therapy protocols. Herein, we highlighted the most common monogenetic liver disorders, followed by proposed genetic engineering approaches, offered as promising therapeutic modalities.
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BACKGROUND: This research follows some investigations through neural tissue engineering, including fabrication, surface treatment, and evaluation of novel self-stimuli conductive biocompatible and degradable nanocomposite scaffolds. METHODS: Gelatin as a biobased material and polyvinylidene fluoride (PVDF) as a mechanical, electrical, and piezoelectric improvement agent were co-electrospun. In addition, polyaniline/graphene (PAG) nanoparticles were synthesized and added to gelatin solutions in different percentages to induce electrical conductivity. After obtaining optimum PAG percentage, cold atmospheric plasma (CAP) treatment was applied over the best samples by different plasma variable parameters. Finally, the biocompatibility of the scaffolds was analyzed and approved by in vitro tests using two different PC12 and C6 cell lines. In the present study the morphology, FTIR, dynamic light scattering, mechanical properties, wettability, contact angle tests, differential scanning calorimetric, rate of degradation, conductivity, biocompatibility, gene expression, DAPI staining, and cell proliferation were investigated. RESULTS: The PAG percentage optimization results revealed fiber diameter reduction, conductivity enhancement, young's modulus improvement, hydrophilicity devaluation, water uptake decrement, and degradability reduction in electrospun nanofibers by increasing the PAG concentration. Furthermore, ATR-FTIR, FE-SEM, AFM, and contact angle tests revealed that helium CAP treatment improves scaffold characterizations for 90 s in duration time. Furthermore, the results of the MTT assay, FE-SEM, DAPI staining, and RT-PCR revealed that samples containing 2.5% w/w of PAG are the most biocompatible, and CAP treatment increases cell proliferation and improves neural gene expression in the differentiation medium. CONCLUSIONS: According to the results, the samples with the 2.5% w/w of PAG could provide a suitable matrix for neural tissue engineering in terms of physicochemical and biological.
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Grafito , Nanofibras , Gases em Plasma , Proliferación Celular , Conductividad Eléctrica , Polímeros de Fluorocarbono , Gelatina/química , Grafito/química , Nanofibras/química , Poliésteres/química , Polivinilos , Ingeniería de Tejidos/métodos , Andamios del Tejido/químicaRESUMEN
Malaria is a deadly disease in humans caused by the Plasmodium parasite. High prevalence of malaria and resistance of malaria parasite to currently proposed drugs have increased the need to introduce and use new and effective antimalarial agents. In this study, eosin B was used as an effective antimalarial agent, the efficacy of which has already been confirmed by in vitro models. Also, for efficacy and safety improvement of eosin B, liposomal nanocarrier was used because of diversity and adaptability in controlled drug delivery and targeting. Eosin B was trapped inside liposomal nanocarriers by thin layer hydration method and its optimization was performed based on size, polydispersity index, and drug entrapment efficiency. Finally, the eosin B-loaded liposomes were tested on Plasmodium falciparum in culture to evaluate its anti-plasmodial effect. According to the results, the formulation with DSPC:cholesterol 8:1 (molar ratio) and drug concentration of 3 mg/ml was selected as the optimal form. The optimal nano-liposomes showed a size of 163.3 nm, a polydispersity index of 0.250, and an encapsulation efficiency of 69.94%. The process of drug release from nanocarriers was also obtained about 63% at the end of 72 h. Stability studies over 2 months at 25 °C and 4 °C on the optimum sample showed that the samples stored in the refrigerator were more stable in terms of size characteristics, polydispersity index, and drug entrapment efficiency. The results indicate a greater effect of liposomal-formulated eosin B on inhibiting parasite growth compared to the free eosin B.
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Antimaláricos , Malaria , Antimaláricos/uso terapéutico , Eosina I Azulada , Humanos , Liposomas , Malaria/tratamiento farmacológico , Plasmodium falciparumRESUMEN
BACKGROUND: HIV-1 TAT protein is essential for the regulation of viral genome transcription. The first exon of TAT protein has a fundamental role in the stimulation of the extrinsic and intrinsic apoptosis pathways, but its anti-HIV activity is not clear yet. METHODS: In the current study, we firstly cloned the first exon of the TAT coding sequence in the pET-24a expression vector and then protein expression was done in the Rosetta expression host. Next, the expressed TAT protein was purified by Ni-NTA column under native conditions. After that, the protein yield was determined by Bradford kit and NanoDrop spectrophotometry. Finally, the cytotoxicity effect and anti-Scr-HIV-1 activity of the recombinant TAT protein alone and along with Tenofovir drug were assessed by MTT and ELISA, respectively. RESULTS: The recombinant TAT protein was successfully generated in E. coli, as confirmed by 13.5% SDS-PAGE and western blotting. The protein yield was ~150-200 µg/ml. In addition, the recombinant TAT protein at a certain dose with low toxicity could suppress Scr-HIV replication in the infected HeLa cells (~30%) that was comparable with a low toxic dose of Tenofovir drug (~40%). It was interesting that the recombinant TAT protein could enhance anti-HIV potency of Tenofovir drug up to 66%. CONCLUSION: Generally, a combination of TAT protein and Tenofovir drug could significantly inhibit HIV-1 replication. It will be required to determine their mechanism of action in the next studies.
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Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/genética , Proteínas Recombinantes de Fusión/farmacología , Tenofovir/farmacología , Tenofovir/uso terapéutico , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/efectos de los fármacos , Combinación de Medicamentos , Regulación Viral de la Expresión Génica/efectos de los fármacos , Humanos , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/uso terapéuticoRESUMEN
Corneal transplantation, by which the damaged cornea is replaced by a new one, suffers from limited access to HLA-compatible-donors and high maintenance and surgical costs. Therefore, artificial corneas are considered as alternative tools with promising prospects. In our previous study, a two-part-polymeric artificial cornea was composed of enhanced hydrophilic surface electrospun poly(ε-caprolactone) nanofibrous scaffold that is thermally connected to a polyvinyl alcohol-based hydrogel disk was prepared. Characterization tests revealed the prepared artificial cornea had similar biocompatible and structural characteristics regarding the natural cornea. In current study, human amniotic membrane extract containing growth factors, cytokines, anti-inflammatory factors, and anti-angiogenic factors was prepared, nano-encapsulated in chitosan-dextran nanoparticles, and physically decorated on the poly(ε-caprolactone)-polyvinyl-alcohol artificial cornea. Physicochemical and biological characterizations revealed the nano-decorated artificial cornea has more biocompatibility than the unmodified one. Our study demonstrated the bioactive macromolecules loaded on chitosan-dextran nanoparticles enhanced the anti-angiogenic property of artificial cornea through the sustained release of anti-angiogenic factors such as thrombospondin-1, endostatin, and heparin sulfate proteoglycan. Real-time-PCR and flow-cytometry assessments elucidated the vascularization was inhibited through a decrease in the expression of cluster of differentiation 31 and von-Willebrand-Factor. Our study proposed the use of biocompatible artificial cornea could be a promising strategy in corneal transplantation.
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Amnios/química , Quitosano/química , Dextranos/química , Amnios/efectos de los fármacos , Amnios/metabolismo , Materiales Biocompatibles/química , Córnea/efectos de los fármacos , Trasplante de Córnea/métodos , Humanos , Ensayo de Materiales , Nanopartículas/química , Polímeros/química , Alcohol Polivinílico/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/químicaRESUMEN
Niosomes, as a kind of drug delivery system, is widely used for the topical delivery of lipophilic drugs. Optimization of niosomes plays an essential role in enhancing their therapeutic efficiencies. This study aims to prepare an optimized niosomal formulation of simvastatin (nSIM), a lipophilic member of statins, through the experiment (Response Surface methodology). Optimized niosomes were characterized in size, polydispersity index (PDI), entrapment efficiency (EE), stability, releasing pattern, and antimicrobial activity. The different molar ratio of surfactant and cholesterol were applied to prepare various formulation of simvastatin loaded niosome. Mean particle size and size distribution were analyzed by dynamic light scattering. Antibacterial activity was determined by MIC and MBC tests against Staphylococcus aureus and Escherichia coli. The release rate of simvastatin from noisome nanoparticles was studied by the Franz diffusion cell method. The release pattern was studied through zero order, first order, Higuchi, Korsmeyer-Peppas, and Hixson-Crowell kinetics models. Optimized niosomes were obtained by span 80, drug to cholesterol ratio of 0.4 with 7 min sonication time. Mean particle size, PDI, zeta potential, and entrapment efficiency (EE%) of optimized nSIM were obtained about 168 nm, 0.34, -32.40, and 96 %, respectively. The niosomes significantly decreased the drug's releasing rate and enhanced antibacterial activity against S. aureus and E. Coli. It was found that the release pattern of drug followed the Higuchi kinetic model which means drug release is by diffusion. Overall, our findings indicated that the prepared simvastatin loaded niosomes showed good stability and biological properties than free drug. Our study suggests that niosomal formulation could be considered as a promising strategy for the delivery of poor water-soluble drugs that enhance antibacterial activity.
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Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Nanopartículas/química , Simvastatina/farmacología , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/química , Sistemas de Liberación de Medicamentos , Geles/química , Liposomas/química , Pruebas de Sensibilidad Microbiana , Simvastatina/químicaRESUMEN
OBJECTIVE: The objective of this study was to use nano-niosomal formulations to deliver simvastatin as a poor-water soluble drug into breast cancer cells. SIGNIFICANCE: Our study focused on the problem associated with poor water-soluble drugs which have significant biological activity in vivo. METHODS: Different niosomal formulations of simvastatin were prepared and characterized in terms of morphology, size, encapsulation efficiency (EE), and release kinetic. Antiproliferative activity and the mechanism were assessed by quantitative real-time PCR and flow cytometry. Moreover, confocal microscopy was employed to analyze the cell uptake of simvastatin loaded niosomes to the cancerous cells. RESULTS: Size, polydispersity index (PDI), and EE of the best formulation were obtained as 164.8 nm, 0.232, and 97%, respectively. The formulated simvastatin had a spherical shape and showed a slow release profile of the drug after 72 h. Stability data elucidated an increase in mean diameter and PDI which was lower for 4 °C than 25 °C. Confocal microscopy showed the localization of drug loaded niosomes in the cancer cells. The MTT assay revealed both free drug and drug loaded niosomes exhibited a dose-dependent cytotoxicity against breast cancer cells (MDA-MB-231 cells). Flow cytometry and qPCR analysis revealed drug loaded niosomes exert their cytotoxicity on cancerous cells via regulation of apoptotic and anti-apoptotic genes. CONCLUSION: The prepared niosomal simvastatin showed good physicochemical and biological properties than free drug. Our study suggests that niosomal delivery could be considered as a promising strategy for the delivery of poor water-soluble drugs to cancer cells.
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Liposomas/química , Neoplasias , Simvastatina , Tamaño de la Partícula , Simvastatina/farmacologíaRESUMEN
BACKGROUND: Human amniotic membrane grafting could be potentially useful in ocular surface complications due to tissue similarity and the presence of factors that reduce inflammation, vascularization, and scarring. However, considerations like donor-derived infectious risk and the requirement of an invasive surgery limit the clinical application of such treatments. Moreover, the quick depletion of bioactive factors after grafting reduces the efficacy of treatments. Therefore, in the current study, the possibility of nano delivery of the bioactive factors extracted from the human amniotic membrane to the ocular surface was investigated. MATERIALS AND METHODS: Nanoparticles were prepared using polyelectrolyte complexation from chitosan and dextran sulfate. The effect of polymer ratio, pH, and the amount of extract on particle size and encapsulation efficacy were studied using Box-Behnken response surface methodology. RESULTS: The optimum condition was obtained as follows: 4.9:1 ratio of dextran sulfate to chitosan, 600 µL amniotic membrane extract, and pH of 6. The prepared nanoparticles had an average size of 213 nm with 77% encapsulation efficacy. In the release test, after 10 days, approximately 50% of entrapped bioactive proteins were released from the nanocarriers in a controlled manner. Biological activity assessment on endothelial cells revealed amniotic membrane extract loaded nanoparticles had a longer and significant increase in anti-angiogenic effect when compared to the control. CONCLUSION: Our data elucidate the ability of nanotechnology in ocular targeted nano delivery of bioactive compounds.
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Amnios/química , Inhibidores de la Angiogénesis/farmacología , Portadores de Fármacos/química , Nanopartículas/química , Proyectos de Investigación , Extractos de Tejidos/farmacología , Inhibidores de la Angiogénesis/administración & dosificación , Inhibidores de la Angiogénesis/aislamiento & purificación , Proliferación Celular , Células Cultivadas , Quitosano/química , Composición de Medicamentos , Liberación de Fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Tamaño de la Partícula , Propiedades de Superficie , Extractos de Tejidos/administración & dosificación , Extractos de Tejidos/aislamiento & purificaciónRESUMEN
PURPOSE: Staphylococcus aureus is the most common persistent pathogen in humans, so development of new formulations to combat pathogen invasion is quite necessary. METHODS: In the current study, for the first time, the synergistic activity of recombinant lysostaphin and LL-37 peptide was studied against S. aureus. Moreover, different niosomal formulations of the peptide and protein were prepared and analyzed in terms of size, shape, zeta potential, and entrapment efficiency. Also, a long-term antibacterial activity of the best niosomal formulation and free forms was measured against S. aureus in vitro. RESULTS: The optimal niosomal formulation was obtained by mixing the surfactants (span60 and tween60; 2:1 w/w), cholesterol, and dicetylphosphate at a ratio of 47:47:6, respectively. They showed uniform spherical shapes with the size of 565 and 325 nm for lysostaphin and LL-37, respectively. This formulation showed high entrapment efficiency for the peptide, protein, and a slow-release profile over time. Release kinetic was best fitted by Higuchi model indicating a diffusion-based release of the drugs. The lysostaphin/LL-37 niosomal formulation synergistically inhibited growth of S. aureus for up to 72 hours. However, the same amounts of free forms of both anti-microbial agents could not hold the anti-microbial effect and growth was seen in the following 72 hours. Cytotoxicity assay specified that lysostaphin/LL-37 niosomal combination had no deleterious effect on normal fibroblast cells at effective antimicrobial concentrations. CONCLUSION: This study indicated that the use of lysostaphin in combination with LL-37, either in niosomal or free forms, synergistically inhibited growth of S. aureus in vitro. In addition, niosomal preparation of antimicrobial agents could provide a long-term protection against bacterial infections.
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Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Lisostafina/farmacología , Staphylococcus aureus/efectos de los fármacos , Animales , Antibacterianos/farmacocinética , Péptidos Catiónicos Antimicrobianos/farmacocinética , Liberación de Fármacos , Sinergismo Farmacológico , Fibroblastos/efectos de los fármacos , Liposomas/química , Liposomas/farmacología , Lisostafina/genética , Lisostafina/farmacocinética , Ratones , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacología , Infecciones Estafilocócicas/tratamiento farmacológico , CatelicidinasRESUMEN
PURPOSE: The purpose of the study was to evaluate tissue reaction to polycaprolactone (PCL) nanofiber patches in the cornea, conjunctiva, and anterior chamber (AC) in rabbit eyes and to assess their biocompatibility for use as patch grafts. METHODS: Two 100 µ PCL patches were implanted under the conjunctiva and in the corneal stroma of one albino New Zealand rabbit, and pathologic evaluation was done after 3 weeks. In the next step, two PCL patches were implanted; one in the corneal stroma and the other in the AC of two rabbits followed by pathologic evaluation after 3 months. RESULTS: On slit-lamp examination, there was minimum inflammation in all cases. Pathologic examination showed that the contact and probably merging between the host tissue and PCL fibers were achieved with minimal tissue reaction. CONCLUSION: As a biocompatible material, PCL nanofibers seem to be a promising modality for the repair of different tissue defects including melting, thinning, and perforation. They may also be a suitable material for manufacturing keratoprostheses.
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Cámara Anterior/efectos de los fármacos , Conjuntiva/efectos de los fármacos , Enfermedades de la Córnea/cirugía , Sustancia Propia/efectos de los fármacos , Trasplante de Córnea/métodos , Nanofibras/administración & dosificación , Poliésteres/administración & dosificación , Animales , Cámara Anterior/citología , Apósitos Biológicos , Células Cultivadas , Conjuntiva/citología , Conjuntiva/cirugía , Sustancia Propia/citología , Sustancia Propia/cirugía , Modelos Animales de Enfermedad , Oftalmología/métodos , Complicaciones Posoperatorias/prevención & control , Conejos , Microscopía con Lámpara de HendiduraRESUMEN
PURPOSE: To compare different preparation methods for a suitable amniotic membrane (AM) extract containing a given amount of growth factors. METHODS: In this interventional case series, we dissected the AM from eight placentas within 24 hours after delivery, under clean conditions. After washing and mixing, AM extracts (AMEs) were prepared using pulverization and homogenization methods, and different processing and storing conditions. Main outcome measures were the amount of added protease inhibitor (PI), the relative centrifugal force (g), in-process temperature, repeated extraction times, drying percentage, repeated pulverization times, and the effect of filtering with 0.2 µm filters. Extract samples were preserved at different temperature and time parameters, and analyzed for hepatic growth factor (HGF) and total protein using ELISA and calorimetric methods, respectively. RESULTS: The extracted HGF was 20% higher with pulverization as compared to homogenization, and increased by increasing the PI to 5.0 µl/g of dried AM. Repeating centrifugation up to 3 times almost doubled the extracted HGF and protein. Storing the AME at -170° for 6 months caused a 50% drop in the level of HGF and protein. Other studied parameters showed no significant effect on the extracted amount of HGF or total protein. CONCLUSION: Appropriate extraction methods with an adequate amount of PI increases the level of extractable components from harvested AMs. To achieve the maximal therapeutic effects of AMEs, it is necessary to consider the half-life of its bioactive components.
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The study aimed to fabricate and characterize a 2-part artificial cornea as a substitute for penetrating keratoplasty in patients with corneal blindness. The peripheral part of the artificial cornea consisted of plasma-treated electrospun poly (É-caprolactone) (PCL) nanofibers, which were attached to a hydrogel disc of polyvinyl alcohol (PVA) as a central optical part. The physical properties of the prepared artificial cornea, including morphology, mechanical properties, light transmittance, and contact angle, were assessed. Cell attachment and proliferation studies were performed on rabbit limbal stem cells. The SEM image of the polymeric system showed that the peripheral part formed a highly porous scaffold that could facilitate tissue biointegration. Assessment of the mechanical properties of the peripheral nanofibrous part and the hydrogel optical part showed suitable elasticity. Young's modulus values of the electrospun PCL skirt and PVA hydrogel core were 7.5 and 5.3 MPa, respectively, which is in line with the elasticity range of natural human cornea (0.3-7 MPa). The light transmittance of the central part was >85% when measured in the 400-800 nm wavelength range. The plasma-treated PCL nanofibrous scaffold promoted limbal stem cell adhesion and proliferation within 10 days. These results confirmed that the polymeric artificial cornea showed suitable physical properties and good biocompatibility and epithelialization ability.