Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Curr Nutr Rep ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656688

RESUMO

PURPOSE OF REVIEW: Global health concerns persist in the realm of cardiovascular diseases (CVDs), necessitating innovative strategies for both prevention and treatment. This narrative review aims to explore the potential of short-chain fatty acids (SCFAs)-namely, acetate, propionate, and butyrate-as agents in the realm of postbiotics for the management of CVDs. RECENT FINDINGS: We commence our discussion by elucidating the concept of postbiotics and their pivotal significance in mitigating various aspects of cardiovascular diseases. This review centers on a comprehensive examination of diverse SCFAs and their associated receptors, notably GPR41, GPR43, and GPR109a. In addition, we delve into the intricate cellular and pharmacological mechanisms through which these receptors operate, providing insights into their specific roles in managing cardiovascular conditions such as hypertension, atherosclerosis, heart failure, and stroke. The integration of current information in our analysis highlights the potential of both SCFAs and their receptors as a promising path for innovative therapeutic approaches in the field of cardiovascular health. The idea of postbiotics arises as an optimistic and inventive method, presenting new opportunities for preventing and treating cardiovascular diseases.

2.
Artigo em Inglês | MEDLINE | ID: mdl-37921126

RESUMO

Antimicrobial peptides (AMPs), a class of antimicrobial agents, possess considerable potential to treat various microbial ailments. The broad range of activity and rare complete bacterial resistance to AMPs make them ideal candidates for commercial development. These peptides with widely varying compositions and sources share recurrent structural and functional features in mechanisms of action. Studying the mechanisms of AMP activity against bacteria may lead to the development of new antimicrobial agents that are more potent. Generally, AMPs are effective against bacteria by forming pores or disrupting membrane barriers. The important structural aspects of cytoplasmic membranes of pathogens and host cells will also be outlined to understand the selective antimicrobial actions. The antimicrobial activities of AMPs are related to multiple physicochemical properties, such as length, sequence, helicity, charge, hydrophobicity, amphipathicity, polar angle, and also self-association. These parameters are interrelated and need to be considered in combination. So, gathering the most relevant available information will help to design and choose the most effective AMPs.

3.
Iran J Basic Med Sci ; 26(6): 635-644, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37275756

RESUMO

Objectives: Today, the non-covalent PEGylation methods of protein pharmaceuticals attract more attention and possess several advantages over the covalent approach. In the present study, Amino Acid-mPEGs (aa-mPEGs) were synthesized, and the human Growth Hormone (hGH) stability profile was assessed in their presence and absence. Materials and Methods: aa-mPEGs were synthesized with different amino acids (Trp, Glu, Arg, Cys, and Leu) and molecular weights of polymers (2 and 5 KDa). The aa-mPEGs were analyzed with different methods. The physical and structural stabilities of hGH were analyzed by SEC and CD spectroscopy methods. Physical stability was assayed at different temperatures within certain intervals. Molecular dynamics (MD) simulation was used to realize the possible mode of interaction between protein and aa-mPEGs. The cell-based method was used to evaluate the cytotoxicity. Results: HNMR and FTIR spectroscopy indicated that aa-mPEGs were successfully synthesized. hGH as a control group is known to be stable at 4 °C; a pronounced change in monomer degradation is observed when stored at 25 °C and 37 °C. hGH:Glu-mPEG 2 kDa with a molar ratio of 1:1 to the protein solution can significantly increase the physical stability. The CD spectroscopy method showed that the secondary structure of the protein was preserved during storage. aa-mPEGs did not show any cytotoxicity activities. The results of MD simulations were in line with experimental results. Conclusion: This paper showed that aa-mPEGs are potent excipients in decreasing the aggregation of hGH. Glu-mPEG exhibited the best-stabilizing properties in a harsh environment among other aa-mPEGs.

4.
Curr Pharm Biotechnol ; 23(15): 1851-1863, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35410594

RESUMO

Probiotics are defined as "live microorganisms that confer a health benefit on the host when administered adequately." In recent years, the cosmetic industry has tried to develop many products classified as probiotics. They can exert their benefits at the skin level because of their favorite properties, and they could prevent and treat skin diseases and represent an emerging area for skin health. The antibacterial and immunomodulatory properties make them promising candidates to target skin disorders including acne, psoriasis, and atopic dermatitis and aid wound healing. The scientific reports show that specific probiotic strains can modulate cutaneous microflora, skin immune system, lipid barrier, and skin health preservation. This review summarizes the most relevant evidence from scientific literature concerning potential topical applications of probiotics in dermatology. Altogether, the evidence reported here affords the possibility of designing new strategies based on a topical approach to prevent and treat cutaneous disorders.


Assuntos
Dermatite Atópica , Probióticos , Humanos , Probióticos/uso terapêutico , Dermatite Atópica/tratamento farmacológico , Pele , Antibacterianos , Lipídeos
5.
Adv Pharm Bull ; 11(4): 684-692, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34888215

RESUMO

Purpose: Microbial biofilms are one of the main causes of persistent human infections. Encapsulation of an antibiotic and a biofilm dispersal agent within a nano-carrier has been recognized as a novel approach to combat the problem of biofilm-related infections. Here, we develop the nanoliposomal formulation for delivery of vancomycin in combination with cis-2- decenoic acid (C2DA), to Staphylococcus epidermidis biofilm. The effects of the formulations were studied at two stages: biofilm growth inhabitation and biofilm eradication. Methods: Liposomal formulations were prepared by the solvent evaporation dehydration-rehydration method and were evaluated for size, zeta potential, and encapsulation efficacy. The ability of different agents in free and encapsulated forms were assessed to evaluate the anti-biofilm activities. Results: Vancomycin and C2DA were successfully co-encapsulated in the same nanoliposome (liposomal combination). The zeta potential values of the liposomal formulations of vancomycin, C2DA, and the liposomal combination were 37.2, 40.2, 51.5 mV, and the mean sizes of these liposomal formulations were 167.8±1.5, 215.5±8.8, 235.5±0.01, respectively. Encapsulation efficacy of C2DA was 65% and about 40% for vancomycin. The results indicated that liposomal combination exerted strong anti-biofilm activities, slightly exceeding those observed by the free form of a combination of vancomycin and C2DA, but higher than either agent used alone in their free forms. The anti-biofilm activity of formulations followed concentration and time-dependent manner. Conclusion: The combination of vancomycin and C2DA could inhibit biofilm formation. Employing the liposomal combination is a considerable method to remove bacterial biofilm.

6.
Antibiotics (Basel) ; 10(9)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34572626

RESUMO

The extensive usage of antibiotics and the rapid emergence of antimicrobial-resistant microbes (AMR) are becoming important global public health issues. Many solutions to these problems have been proposed, including developing alternative compounds with antimicrobial activities, managing existing antimicrobials, and rapidly detecting AMR pathogens. Among all of them, employing alternative compounds such as phytochemicals alone or in combination with other antibacterial agents appears to be both an effective and safe strategy for battling against these pathogens. The present review summarizes the scientific evidence on the biochemical, pharmacological, and clinical aspects of phytochemicals used to treat microbial pathogenesis. A wide range of commercial products are currently available on the market. Their well-documented clinical efficacy suggests that phytomedicines are valuable sources of new types of antimicrobial agents for future use. Innovative approaches and methodologies for identifying plant-derived products effective against AMR are also proposed in this review.

7.
Curr Microbiol ; 77(9): 1959-1967, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32623484

RESUMO

Acinetobacter species are defined as multidrug-resistant pathogens and the development of resistance against antimicrobials is a major problem in the treatment of infections caused by them. This study aimed to evaluate the antibacterial activity of aqueous and methanol extracts of Salvia chorassanica and Artemisia khorassanica on multidrug-resistant Acinetobacter isolates and also examining the interaction of the methanol extract of the plants with the combination of amikacin and imipenem. First, the presence of adeI and adeB genes in bacterial isolates was investigated. The aqueous and methanol extracts of the leaves of the plants were prepared by Maceration method. Minimum Inhibition Concentration (MIC) values were determined to evaluate the antibacterial activities of plant extracts and antibiotics. Combined effects of the antibiotics with plant extracts were performed using the checkerboard method. The accumulation assay was used to examine the inhibitory effects of plant extracts on the bacterial efflux pump. MIC results indicated that the methanol extracts were effective against Acinetobacter species. FICI values indicated that the combination of antibiotics with methanol plant extracts improves bacterial sensitivity to antibiotics. The extracts also exhibited efflux pump inhibitory activities. Consequently, combination of the plant extracts with antibiotics could enhance the antibiotic susceptibility of resistant pathogens.


Assuntos
Acinetobacter baumannii , Imipenem , Amicacina , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Imipenem/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia
8.
Iran J Basic Med Sci ; 23(4): 551-555, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32489571

RESUMO

OBJECTIVES: The in vivo efficacy of nanoliposomal formulation of vancomycin against methicillin-resistant Staphylococcus aureus (MRSA) assessed. MATERIALS AND METHODS: Nanoliposomal formulations were prepared and characterized. The in vivo study was carried out on rabbits which received liquid culture medium containing MRSA under anesthesia. After 48 hr, the eyes treated with the liposomal and free form of vancomycin. The rabbits were euthanized at predesignate intervals at 12, 24, 48, 96, 144 hr intervals injection. The antibacterial activity of different vancomycin formulations was assayed by the time killing method. RESULTS: The zeta potential, mean sizes and encapsulation efficacy of liposomal vancomycin were 29.7 mV, 381.93±30.13 nm and 47%, respectively. The results of time-killing studies indicated that the liposomal formula was more effective than the free form of vancomycin. CONCLUSION: The results of this study revealed that liposomal vancomycin formulation is a powerful nano-antibacterial agent to combat infectious endophthalmitis.

9.
Curr Drug Deliv ; 17(2): 174-183, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31987020

RESUMO

OBJECTIVE: An injectable long acting In-Situ Forming Gel (ISFG) of human Growth Hormone (hGH) was prepared by using triblock PCL-PEG-PCL (Mw 1500-1500-1500). Ring-Opening Polymerization (ROP) of triblock using microwave was applied. METHODS: The BCA protein assay Kit was used to determine the concentration of hGH in the in-vitro release medium. Finally, Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) tests and Circular Dichroism (CD) spectrum were done to approve the stability of released hGH. The result of ROP demonstrated that the proportion of PCL to PEG accorded with the initial molar ratio of the monomers. The cross-section of the Surface Electron Microscopy (SEM) indicated the porous framework of the hydrogel could load the drug into its tridimensional matrixes structure. There is the low initial burst release of hGH from the supramolecular hydrogel. RESULTS: The maximum in-vitro release of hGH was 71.2 % ± 1.5 that were due to hGH degrading after this time (21 days). The CD spectrum and SDS-PAGE results confirmed the stability of hGH during invitro release evaluation. CONCLUSION: The results suggest that the sustained-release formulation using PCL-PEG-PCL can be applied to control the release of hGH.


Assuntos
Hormônio do Crescimento Humano/química , Hidrogéis/química , Poliésteres/química , Polietilenoglicóis/química , Preparações de Ação Retardada/química , Liberação Controlada de Fármacos , Injeções , Temperatura
10.
Artigo em Inglês | MEDLINE | ID: mdl-31346459

RESUMO

Microbial resistance to classical antibiotics and its rapid progression have raised serious concern in the treatment of infectious diseases. Recently, many studies have been directed towards finding promising solutions to overcome these problems. Phytochemicals have exerted potential antibacterial activities against sensitive and resistant pathogens via different mechanisms of action. In this review, we have summarized the main antibiotic resistance mechanisms of bacteria and also discussed how phytochemicals belonging to different chemical classes could reverse the antibiotic resistance. Next to containing direct antimicrobial activities, some of them have exerted in vitro synergistic effects when being combined with conventional antibiotics. Considering these facts, it could be stated that phytochemicals represent a valuable source of bioactive compounds with potent antimicrobial activities.


Assuntos
Antibacterianos/farmacologia , Bactérias/genética , Compostos Fitoquímicos/farmacologia , Bactérias/efeitos dos fármacos , Membrana Externa Bacteriana/efeitos dos fármacos , Proteínas de Bactérias/genética , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Sinergismo Farmacológico , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Humanos , Compostos Fitoquímicos/uso terapêutico
11.
Pharmacol Res ; 146: 104289, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31152788

RESUMO

Tuberculosis (TB) is currently a clinical and public health problem. There is a concern about the emergence and development of multidrug-resistant (MDR-TB) and extensively drug-resistant (XDR-TB) species. Additionally, the lack of effective vaccines is another limitation to control the related infections. To overcome these problems various approaches have been pursued such as finding novel drug candidates with a new mechanism of action or repurposing conventional antibiotics. However, these strategies are still far from clinical application. Hence, the use of adjunctive therapy has been suggested for TB. In this paper, we review non-antibiotic adjunctive treatment options for TB. Natural products, vitamins, micronutrients, and trace elementals, as well as non-antibiotic drugs, are examples of agents which have been used as adjunctive therapies. The use of these adjunctive therapies has been shown to improve disease outcomes and reduce the adverse effects of antibiotic drugs. Employing these agents, either alone or in combination with antibiotics, might be considered as a promising approach to control TB infections and achieve better clinical outcomes. However, supportive evidence from randomized controlled trials is still scant and merits further investigations.


Assuntos
Produtos Biológicos/uso terapêutico , Oligoelementos/uso terapêutico , Tuberculose/tratamento farmacológico , Vitaminas/uso terapêutico , Animais , Antituberculosos/uso terapêutico , Humanos , Mycobacterium tuberculosis
12.
J Pharmacopuncture ; 22(1): 49-54, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30989001

RESUMO

OBJECTIVE: Antibiotic resistance is a global health problem and threatens health of societies. These problems have led to a search for alternative approaches such as combination therapy. The aim of the present study was to investigate the effect of caffeine and omeprazole in combination with gentamicin or ciprofloxacin against standard and clinically resistant isolates of Staphylococcus aureus and Escherichia coli. METHODS: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of different agents against bacterial strains were determined. The interaction of non- antibiotic drugs with gentamicin and ciprofloxacin was studied in vitro using a checkerboard method and calculating fraction inhibitory concentration index (FICI). Verapamil as efflux pump inhibitor was used to evaluate the possible mechanism of bacterial resistance to antibiotics. RESULTS: The MIC and MBC values of gentamicin against bacterial strains were in the range of 20- 80 µg/ml and 40-200 µg/ml, respectively. Caffeine and omeprazole had no intrinsic inhibitory activity against tested microorganisms. However, upon combination of caffeine with antibiotics, the synergistic effects were observed. Verapamil was able to reduce the MIC values of gentamicin (4 folds) only in some bacterial strains. CONCLUSION: These findings indicated that caffeine was effective in removing bacterial infection caused by S. aureus and E. coli. The relevant mechanisms of antibiotic resistance were not related to the drug efflux.

13.
Rep Biochem Mol Biol ; 7(2): 189-195, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30805399

RESUMO

BACKGROUND: The quality of extracts used in the skin prick test directly influences the interpretation of the test. Accordingly, the outcomes and effectiveness of immunotherapy for the management of IgE-mediated allergies depend on the quality of the extracts used. Excipients, which are pharmacologically inert ingredients, are intentionally added to the active ingredients. The aim of this study was to address optimum excipients for stability Platanus (P.) orientalis extract. METHODS: In this study the excipients examined were l-lysine (20 mM), l-cysteine (20 mM), albumin (0.5%), sorbitol (2%), sucrose (750 mM), trehalose (20 mM), D-mannitol (2% w/v), urea (100 mM) and Tween-20 (0.1%). Their effects on P. orientalis extract stability were analyzed using an inhibition enzyme linked immune assay at 37 °C. RESULTS: A mixture of lysine (20 mM), trehalose (20 mM), and D-mannitol (2% w/v) conferred the greatest stability on the P. orientalis extract. CONCLUSION: The P. orientalis extract stability was increased by a mixture of lysine (20 mM), trehalose (20 mM), and D-mannitol.

14.
Phytother Res ; 33(1): 13-40, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30346068

RESUMO

Based on World Health Organization reports, resistance of bacteria to well-known antibiotics is a major global health challenge now and in the future. Different strategies have been proposed to tackle this problem including inhibition of multidrug resistance pumps and biofilm formation in bacteria and development of new antibiotics with novel mechanism of action. Flavonoids are a large class of natural compounds, have been extensively studied for their antibacterial activity, and more than 150 articles have been published on this topic since 2005. Over the past decade, some promising results were obtained with the antibacterial activity of flavonoids. In some cases, flavonoids (especially chalcones) showed up to sixfold stronger antibacterial activities than standard drugs in the market. Some synthetic derivatives of flavonoids also exhibited remarkable antibacterial activities with 20- to 80-fold more potent activity than the standard drug against multidrug-resistant Gram-negative and Gram-positive bacteria (including Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus). This review summarizes the ever changing information on antibacterial activity of flavonoids since 2005, with a special focus on the structure-activity relationship and mechanisms of actions of this broad class of natural compounds.


Assuntos
Antibacterianos/uso terapêutico , Flavonoides/uso terapêutico , Relação Estrutura-Atividade , Antibacterianos/farmacologia , Flavonoides/farmacologia , Humanos , Estrutura Molecular
15.
Avicenna J Phytomed ; 8(3): 246-253, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29881710

RESUMO

OBJECTIVE: In recent years, there has been an increasing interest in using herbal products to overcome bacterial resistance. The aim of this study was to investigate the effect of lemon verbena aqueous extract, verbascoside and caffeine in combination with gentamicin against standard and clinical isolates of Staphylococcus aureus and Escherichia coli strains. MATERIALS AND METHODS: The MIC and MBC values of different antibacterial agents against bacterial strains were determined. The effect of co-administration lemon verbena extract, verbascoside, and caffeine and gentamicin was studied in vitro using a checkerboard method and calculating fraction inhibitory concentration index (FICI). RESULTS: Herbal extract, verbascoside and caffeine alone showed no inhibitory effects on any of the bacterial strains (at doses up to 200 g/ml). Herbal extract, verbascoside and caffeine were able to decrease the MIC of gentamicin against the standard resistant strains and two clinical isolates. Among these combinations, the co-administration of verbascoside and gentamicin was more effective and synergistic activities (FICI<1) against clinical isolates were observed. . CONCLUSION: The results of the present study revealed that herbal extract, verbascoside and caffeine potentiated the antimicrobial action of gentamicin against some clinical isolates of S. aureus and E. coli.

16.
Drug Dev Ind Pharm ; 43(10): 1619-1625, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28489426

RESUMO

Raloxifene hydrochloride (RLX) is a selective estrogen receptor modulator which is orally used for treatment of osteoporosis and prevention of breast cancer. The drug has low aqueous solubility and bioavailability. The aim of the present study is to formulate and characterize oil-in-water microemulsion systems for oral delivery of RLX. To enhance the drug aqueous solubility, microemulsion based on sesame oil was prepared. Sesame oil and Tween 80 were selected as the drug solvent oil and surfactant, respectively. In the first and second formulations, Edible glycerin and Span 80 were applied as co-surfactant, respectively. Pseudo-ternary phase diagrams showed that the best surfactant/co-surfactant ratios in the first and second formulations were 4:1 and 9:1, respectively. The particle size of all free drug-loaded and drug loaded samples were in the range of 31.25 ± 0.3 nm and 60.9 ± 0.1 nm, respectively. Electrical conductivity coefficient and refractive index of all microemulsion samples confirmed the formation of oil-in-water type of microemulsion. In vitro drug release profile showed that after 24 hours, 46% and 63% of the drug released through the first formulation in 0.1% (w/v) Tween 80 in distilled water as a release medium and phosphate buffer solution (PBS) at pH = 5.5, respectively. These values were changed to 57% and 98% for the second formulation. Results confirmed that the proposed microemulsion system containing RLX could improve and control the drug release profile in comparison to conventional dosage form.


Assuntos
Emulsões/química , Glicerol/química , Polissorbatos/química , Cloridrato de Raloxifeno/química , Tensoativos/química , Disponibilidade Biológica , Química Farmacêutica , Liberação Controlada de Fármacos , Cloridrato de Raloxifeno/antagonistas & inibidores , Solubilidade
17.
Pharm Biol ; 55(1): 212-217, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27927058

RESUMO

CONTEXT: Nasal mucosa is a desirable route for mucosal vaccine delivery. Mucosal co-administration of chitosan nanoparticles with absorption enhancers such as cross-linked dextran microspheres (CDM, Sephadex®) is a promising antigen delivery system. OBJECTIVE: In the current study, the chitosan nanospheres loaded with tetanus toxoid (CHT:TT NPs) was prepared and characterized. The immune responses against tetanus toxoid after nasal administration of CHT:TT NPs alone or mixed with CDM were also determined. MATERIALS AND METHODS: Chitosan nanospheres were prepared by ionic gelation method. Particle size, releasing profile and antigen stability were evaluated by dynamic light scattering, diffusion chamber and SDS-PAGE methods, respectively. Rabbits were nasally immunized with different formulations loaded with 40 Lf TT. After three times immunizations with 2 weeks intervals, sera IgG titres and nasal lavage sIgA titres were determined. RESULTS: Mean size of CHT NPs and CHT:TT NPs were 205 ± 42 nm and 432 ± 85 nm, respectively. The release profile showed that 42.4 ± 10.5% of TT was released after 30 min and reached to a steady state after 1.5 h. Stability of encapsulated TT in nanospheres was confirmed by SDS-PAGE. The antibody titres showed that CHT:TT NPs-induced antibody titres were higher than TT solution. CHT NPs mixed with CDM induced the systemic IgG and nasal lavage sIgA titres higher than intranasal administration of TT solution (p < 0.001). DISCUSSION AND CONCLUSION: As the results indicated, these CHT:TT NPs when co-administered with CDM were able to induce more immune responses and have the potential to be used in mucosal immunization.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Quitosana/administração & dosagem , Reagentes de Ligações Cruzadas/química , Dextranos/administração & dosagem , Portadores de Fármacos , Nanosferas , Mucosa Nasal/efeitos dos fármacos , Toxoide Tetânico/administração & dosagem , Adjuvantes Imunológicos/química , Administração Intranasal , Animais , Quitosana/química , Quitosana/imunologia , Dextranos/química , Dextranos/imunologia , Composição de Medicamentos , Estabilidade de Medicamentos , Difusão Dinâmica da Luz , Eletroforese em Gel de Poliacrilamida , Imunidade nas Mucosas/efeitos dos fármacos , Esquemas de Imunização , Imunoglobulina A Secretora/metabolismo , Imunoglobulina G/sangue , Microesferas , Mucosa Nasal/imunologia , Mucosa Nasal/metabolismo , Tamanho da Partícula , Coelhos , Solubilidade , Toxoide Tetânico/química , Toxoide Tetânico/imunologia , Fatores de Tempo
18.
Pharm Dev Technol ; 22(1): 122-129, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27585481

RESUMO

In this study several ciprofloxacin (CFX) imprinted and non-imprinted hydrogels were prepared and evaluated as ocular drug delivery systems in aqueous media. 2-Hydroxyethyl methacrylate (HEMA) was used as a solvent and backbone monomer, ethylene glycol dimethacrylate (EGDMA) as a cross-linker, methacrylic acid (MAA) as a functional monomer and CFX as the template molecule. CFX-imprinted hydrogels (MIPs) were prepared applying different CFX:MAA molar ratios (1:16, 1:20 and 1:32) in feed composition of monomer solutions. Thermal polymerization was applied and hydrogels were synthesized in a polypropylene mold (0.4 mm thickness). Swelling and binding properties of hydrogels were evaluated in water. Release profile of the MIPs was evaluated in NaCl (0.9%) and artificial tears. The data showed that enhancing the MAA concentration, as a co-monomer, and using molecular imprinting improved binding properties of the synthesized hydrogels. The optimized MIPs with 400 mM MAA and CFX: MAA molar ratio of 1:20 and 1:16 showed the greatest affinity for CFX and the highest ability to control drug release. In vitro antibacterial activity of hydrogels was studied and demonstrated the effect of CFX-loaded hydrogels against Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) isolated from patients' eyes. This study indicated antibacterial efficacy of CFX-loaded MIP hydrogels.


Assuntos
Antibacterianos/administração & dosagem , Ciprofloxacina/administração & dosagem , Preparações de Ação Retardada/química , Hidrogéis/química , Metacrilatos/química , Impressão Molecular/métodos , Antibacterianos/química , Antibacterianos/farmacologia , Ciprofloxacina/química , Ciprofloxacina/farmacologia , Reagentes de Ligações Cruzadas/química , Liberação Controlada de Fármacos , Humanos , Polimerização , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos
19.
Curr Eye Res ; 41(10): 1286-1293, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27212193

RESUMO

PURPOSE: In the present work, the effect of monomer composition on silver nanoparticles' (SNPs) binding capacity of hydrogels was investigated and their antibacterial efficacy was evaluated. MATERIALS AND METHODS: Three series of poly-hydroxyethyl methacrylate (HEMA) hydrogels were prepared using methacrylic acid (MAA), methacrylamide (MAAM), and 4-vinylpyridine (4VP) as co-monomers, and ethylene glycol dimethacrylate (EGDMA) as cross-linker. SNPs binding capacity of hydrogels was evaluated in different concentrations (2, 10, and 20 ppm). In vitro antibacterial activity of SNP-loaded hydrogels was studied against Pseudomonas aeruginosa (P. aeruginosa) isolated from patients' eyes. Then, inhibitory effect of hydrogels in biofilm formation was evaluated in the presence of Staphylococcus epidermidis (S. epidermidis) (DSMZ 3270). RESULTS: Our data indicated that poly(HEMA-co-MAA-co-EGDMA) had superior binding affinity for SNPs in comparison with other hydrogels. All SNP-loaded hydrogels demonstrated excellent antimicrobial effects at all times against P. aeruginosa and S. epidermidis after soaking in 10 and 20 ppm SNP suspensions. Scanning electron microscope (SEM) images revealed excellent inhibitory effect of SNPs against biofilm formation on the surface of the hydrogels. CONCLUSIONS: This study indicated the effect of monomer compositions in SNP loading capacity of poly(HEMA) hydrogels and antibacterial efficacy of SNP-loaded hydrogels against P. aeruginosa and S. epidermidis, but further in vivo evaluation is necessary.


Assuntos
Antibacterianos/farmacologia , Lentes de Contato Hidrofílicas , Sistemas de Liberação de Medicamentos , Nanopartículas , Pseudomonas aeruginosa/efeitos dos fármacos , Prata/farmacologia , Staphylococcus epidermidis/efeitos dos fármacos , Liberação Controlada de Fármacos , Humanos
20.
Microb Pathog ; 93: 137-44, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26853754

RESUMO

OBJECTIVE: The aim of the present study was to assess the in vitro anti-biofilm activities of solid lipid nanoparticles (SLN) loaded with rifampin against biofilm-producing Staphylococcus epidermidis. METHODS: SLN were prepared and characterized for size, zeta potentials and encapsulation efficacy. The morphological and thermal properties of formulation were evaluated by TEM imagining and DSC analysis. The anti-biofilm activity of different formulations was assessed at different incubation times and concentrations by crystal violet (CV) and viable biofilm count methods. RESULTS: The zeta potentials, particle sizes and encapsulation efficiencies of final formulations were 17 ± 0.7 mV, 101 ± 4.7 nm and approximately 70%; respectively. Rifampin-SLN was able to reduce the biomass of biofilm at time- and concentration-dependent manner. According to biofilm count results, the Rifampin-SLN was more effective for removal of the bacteria with respect to free rifampin. CONCLUSION: The results of this study highlight the advantages and efficiency of Rifampin-SLN in biofilm eradication.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Composição de Medicamentos/métodos , Nanopartículas/química , Rifampina/química , Rifampina/farmacologia , Staphylococcus epidermidis/efeitos dos fármacos , Portadores de Fármacos/química , Humanos , Lipídeos/química , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...