Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Allergy Asthma Clin Immunol ; 17(1): 126, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34872585

RESUMO

BACKGROUND: Dedicator of cytokinesis 2 (DOCK2) deficiency is an inborn error of immunity characterized by cellular and humoral immunological abnormalities leading to early-onset infections. CASE PRESENTATION: We reported a novel case of a 27 months old girl presenting with recurrent pneumonia and a history of skeletal tuberculosis at the age of 19-month-old. Her immunological workup revealed persistent lymphopenia and low CD4 + T cell count along with elevated levels of CD19 +, CD20 +, CD16 +, and CD56 + cells. Furthermore, she had a high level of immunoglobulin (Ig) E and a slightly reduced IgM level with a non-protective antibody titer against diphtheria. The whole-exome sequencing (WES) analysis identified a homozygous frameshift deletion mutation (c.1512delG, p.I505Sfs*28) in exon 16 of the DOCK2 gene. We also conducted electronic searches in PubMed, Web of Science, and Scopus databases and reviewed the articles reporting patients with DOCK2 deficiency. The literature search yielded 14 DOCK2-deficient patients suffering from both cellular and humoral immune defects leading to early-onset infections, particularly human herpesvirus (HHV) infection. CONCLUSION: DOCK2 deficiency should be considered in the context of severe or unusual early-onset infections, especially HHV infections, in a patient with a probable clinical diagnosis of combined immunodeficiency. We also recommended that DOCK2-deficient patients might benefit from T-cell receptor excision circle (TREC) assay as part of the routine newborn screening program.

2.
Mol Immunol ; 137: 57-66, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34216999

RESUMO

Patients with inborn errors of immunity (IEI) present with a heterogeneous clinical and immunological phenotype, therefore a correct molecular diagnosis is crucial for the classification and subsequent therapeutic management. On the other hand, IEI are a group of rare congenital diseases with highly diverse features and, in most cases, an as yet unknown genetic etiology. Next generation sequencing has facilitated genetic examinations of rare inherited disorders during the recent years, thus allowing a suitable molecular diagnosis in the IEI patients. This review aimed to investigate the current findings about these techniques in the field of IEI, suggesting an efficient stepwise approach to molecular diagnosis of inborn errors of immunity.


Assuntos
Doenças Genéticas Inatas/genética , Doenças do Sistema Imunitário/genética , Animais , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Patologia Molecular , Fenótipo
3.
Pediatr Allergy Immunol ; 32(7): 1519-1532, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33963613

RESUMO

BACKGROUND: Autoimmune lymphoproliferative syndrome (ALPS) is a group of genetic disorders characterized by early-onset lymphoproliferation, autoimmune cytopenias, and susceptibility to lymphoma. The majority of ALPS patients carry heterozygous germline mutations in the TNFRSF6 gene. In this study, we conducted a systematic review of patients with ALPS and ALPS-like syndrome. METHODS: The literature search was performed in Web of Science, Scopus, and PubMed databases to find eligible studies. Additionally, the reference list of all included papers was hand-searched for additional studies. Demographic, clinical, immunological, and molecular data were extracted and compared between the ALPS and ALPS-like syndrome. RESULTS: Totally, 720 patients with ALPS (532 genetically determined and 189 genetically undetermined ALPS) and 59 cases with ALPS-like phenotype due to mutations in genes other than ALPS genes were assessed. In both ALPS and ALPS-like patients, splenomegaly was the most common clinical presentation followed by autoimmune cytopenias and lymphadenopathy. Among other clinical manifestations, respiratory tract infections were significantly higher in ALPS-like patients than ALPS. The immunological analysis showed a lower serum level of IgA, IgG, and lymphocyte count in ALPS-like patients compared to ALPS. Most (85%) of the ALPS and ALPS-like cases with determined genetic defects carry mutations in the FAS gene. About one-third of patients received immunosuppressive therapy with conventional or targeted immunotherapy agents. A small fraction of patients (3.3%) received hematopoietic stem cell transplantation with successful engraftment, and all except two patients survived after transplantation. CONCLUSION: Our results showed that the FAS gene with 85% frequency is the main etiological cause of genetically diagnosed patients with ALPS phenotype; therefore, the genetic defect of the majority of suspected ALPS patients could be confirmed by mutation analysis of FAS gene.


Assuntos
Doenças Autoimunes , Síndrome Linfoproliferativa Autoimune , Transtornos Linfoproliferativos , Doenças Autoimunes/genética , Síndrome Linfoproliferativa Autoimune/diagnóstico , Síndrome Linfoproliferativa Autoimune/genética , Heterozigoto , Humanos , Mutação , Fenótipo , Receptor fas/genética
4.
Expert Rev Clin Immunol ; 17(8): 807-817, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33957837

RESUMO

Background: Autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED) is a rare inborn immune error characterized by a triad of chronic mucocutaneous candidiasis (CMC), hypoparathyroidism (HP), and adrenal insufficiency (ADI).Methods: Literature search was conducted in PubMed, Web of Science, and Scopus databases using related keywords, and included studies were systematically evaluated.Results: We reviewed 938 APECED patients and the classic triad of APECED was detected in 57.3% (460 of 803) of patients. CMC (82.5%) was reported as the earliest, HP (84.2%) as the most prevalent, and ADI (72.2%) as the latest presentation within the classic triad. A broad spectrum of non-triad involvements has also been reported; mainly included ectodermal dystrophy (64.5%), infections (58.7%), gastrointestinal disorders (52.0%), gonadal failure (42.0%), neurologic involvements (36.4%), and ocular manifestations (34.3%). A significant positive correlation was detected between certain tissue-specific autoantibodies and particular manifestations including ADI and HP. Neutralizing autoantibodies were detected in at least 60.0% of patients. Nonsense and/or frameshift insertion-deletion mutations were detected in 73.8% of patients with CMC, 70.9% of patients with HP, and 74.6% of patients with primary ADI.Conclusion: Besides penetrance diversity, our review revealed a diverse affected ethnicity (mainly from Italy followed by Finland and Ireland). APECED can initially present in adolescence as 5.2% of the patients were older than 18 years at the disease onset. According to the variety of clinical conditions, which in the majority of patients appear gradually over time, clinical management deserves a separate analysis.


Assuntos
Poliendocrinopatias Autoimunes , Adolescente , Autoanticorpos , Mutação da Fase de Leitura , Humanos , Mutação , Poliendocrinopatias Autoimunes/genética , Fatores de Transcrição
5.
Artigo em Inglês | MEDLINE | ID: mdl-32533820

RESUMO

BACKGROUND: Immunodeficiency, centromeric instability and facial dysmorphism (ICF) syndrome is a rare autosomal recessive immune disorder presenting with hypogammaglobulinemia, developmental delay, and facial anomalies. The ICF type 1, type 2, type 3 and type 4 are characterized by mutations in DNMT3B, ZBTB24, CDCA7 or HELLS gene, respectively. This study aimed to present a comprehensive description of the clinical, immunologic and genetic features of patients with ICF syndrome. METHODS: PubMed, Web of Science, and Scopus were searched systemically to find eligible studies. RESULTS: Forty-eight studies with 118 ICF patients who met the inclusion criteria were included in our study. Among these patients, 60% reported with ICF-1, 30% with ICF-2, 4% with ICF-3, and 6% with ICF-4. The four most common symptoms reported in patients with ICF syndrome were: delay in motor development, low birth weight, chronic infections, and diarrhea. Intellectual disability and preterm birth among patients with ICF-2 and failure to thrive, sepsis and fungal infections among patients with ICF-1 were also more frequent. Moreover, the median levels of all three immunoglobulins (IgA, IgG, IgM) were markedly reduced within four types of ICF syndrome. CONCLUSION: The frequency of diagnosed patients with ICF syndrome has increased. Early diagnosis of ICF is important since immunoglobulin supplementation or allogeneic stem cell transplantation can improve the disease-free survival rate.


Assuntos
Centrômero/genética , Centrômero/imunologia , Face/anormalidades , Doenças da Imunodeficiência Primária/genética , Doenças da Imunodeficiência Primária/imunologia , Agamaglobulinemia/diagnóstico , Agamaglobulinemia/genética , Agamaglobulinemia/imunologia , Anormalidades Craniofaciais/diagnóstico , Anormalidades Craniofaciais/genética , Anormalidades Craniofaciais/imunologia , Humanos , Mutação/genética , Doenças da Imunodeficiência Primária/diagnóstico
6.
Scand J Immunol ; 93(4): e12998, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33190302

RESUMO

SARS-CoV-2 is a novel human coronavirus responsible for the Coronavirus disease 2019 (COVID-19) pandemic. Pneumonia and acute respiratory distress syndrome are the major complications of COVID-19. SARS-CoV-2 infection can activate innate and adaptive immune responses and result in massive inflammatory responses later in the disease. These uncontrolled inflammatory responses may lead to local and systemic tissue damage. In patients with severe COVID-19, eosinopenia and lymphopenia with a severe reduction in the frequency of CD4+ and CD8+ T cells, B cells and natural killer (NK) cells are a common feature. COVID-19 severity hinges on the development of cytokine storm characterized by elevated serum levels of pro-inflammatory cytokines. Moreover, IgG-, IgM- and IgA-specific antibodies against SARS-CoV-2 can be detected in most patients, along with the viral RNA, forming the basis for assays that aid in patient diagnosis. Elucidating the immunopathological outcomes due to COVID-19 could provide potential targets for immunotherapy and are important for choosing the best clinical management by consultants. Currently, along with standard supportive care, therapeutic approaches to COVID-19 treatment involve the use of antiviral agents that interfere with the SARS-CoV-2 lifecycle to prevent further viral replication and utilizing immunomodulators to dampen the immune system in order to prevent cytokine storm and tissue damage. While current therapeutic options vary in efficacy, there are several molecules that were either shown to be effective against other viruses such as HIV or show promise in vitro that could be added to the growing arsenal of agents used to control COVID-19 severity and spread.


Assuntos
Antivirais/uso terapêutico , COVID-19/imunologia , Fatores Imunológicos/uso terapêutico , SARS-CoV-2/fisiologia , COVID-19/diagnóstico , COVID-19/terapia , Teste Sorológico para COVID-19 , Síndrome da Liberação de Citocina , Humanos , Linfopenia , Pandemias , Síndrome do Desconforto Respiratório , Replicação Viral , Tratamento Farmacológico da COVID-19
7.
Expert Rev Clin Immunol ; 16(12): 1227-1235, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33203275

RESUMO

Objectives: Common variable immunodeficiency (CVID) is the most common symptomatic inborn error of immunity characterized by variable clinical manifestations. Methods: Web of Science, Scopus, and PubMed databases were searched systemically to find eligible studies from the earliest available date to February 2020 with standard keywords. Pooled estimates of the autoimmunity prevalence and the corresponding 95% confidence intervals (CI) were calculated using random-effects models. Results: The overall prevalence of autoimmunity was 29.8% (95% CI: 26.4-33.3; I2 = 82.8%). The prevalences of hematologic autoimmune diseases, autoimmune gastrointestinal disorders, autoimmune rheumatologic disorders, autoimmune skin disorders, and autoimmune endocrinopathy in CVID patients were 18.9%, 11.5%, 6.4%, 5.9%), and 2.5%, respectively. There were significantly higher lymphocyte, CD3 + T cell, and CD4 + T cell count among CVID patients without autoimmunity (p< 0.05). Furthermore, failure to thrive, organomegaly, enteropathy, and meningitis was significantly higher in CVID patients with autoimmunity(p< 0.05). Conclusions: Many CVID patients could present with autoimmunity as part of the disease or even as the first or only clinical manifestation of the disease. Care providers may need to pay particular attention to the possible association of these two disorders since the co-occurrence of CVID and autoimmunity could be a misleading clue.


Assuntos
Autoimunidade , Imunodeficiência de Variável Comum/imunologia , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/epidemiologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/fisiopatologia , Imunodeficiência de Variável Comum/diagnóstico , Imunodeficiência de Variável Comum/epidemiologia , Imunodeficiência de Variável Comum/fisiopatologia , Humanos , Prevalência
8.
Artif Cells Nanomed Biotechnol ; 44(2): 497-503, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25289448

RESUMO

The aim of the present study was to formulate methylprednisolone acetate -Eudragit(®) RS100 nanofibers and nanobeads by the electrospinning method. The physicochemical characteristics of the prepared electrospuns were assessed as well. The particle size and morphology were evaluated using scanning electron microscopy. The crystallinity of the drug in the nanofibers and nanobeads obtained was also studied by X-ray crystallography and differential scanning calorimetry (DSC) thermograms. In addition, FT-IR spectroscopy was applied to investigate any possible chemical interaction between the drug and carrier during the preparation process. The drug release kinetics were considered, to predict the release mechanism. Increasing the concentration of the injected solution resulted in the production of more nanofibers and less nanobeads, with the particle size ranging from 100 to 500 nm. The drug crystallinity was decreased during the electrospinning process; however, no interaction between drug and polymer was observed. The electrospuns showed faster drug release pattern compared to the pure drug. The release data were best fitted to the Weibull model, in which the corresponding shape factor values of the model were less than 0.75 indicating the diffusion mechanism of drug release. In conclusion, electrospinning could be considered as a simple and cost effective method for fabricating the drug: polymer nanofibers and nanobeads.


Assuntos
Fenômenos Químicos , Portadores de Fármacos/química , Eletricidade , Metilprednisolona/análogos & derivados , Nanofibras/química , Nanotecnologia/métodos , Ácidos Polimetacrílicos/química , Liberação Controlada de Fármacos , Cinética , Metilprednisolona/química , Acetato de Metilprednisolona
9.
J Biomed Mater Res A ; 103(10): 3148-56, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25773970

RESUMO

Bevacizumab, an anti-VEGF antibody, has demonstrated trustworthy effects in treatment of retinal and choroidal neovascularization that both are crucial sight threatening conditions. However, the weak point is the short half-life of the drug in vitreous which necessitates frequent intravitreal injections. Accordingly employing controlled-release drug delivery systems such as polymeric nanoparticles (NPs) has been suggested. In this study albuminated-PLGA-NPs containing bevacizumab were prepared and studied intended for reducing the number of injections. NPs were formulated by double-emulsion method and a single dose of NPs was intravitreally injected to rabbits. The drug concentrations in vitreous and aqueous humor were assayed in different time intervals using ELISA and intraocular pharmacokinetic parameters were calculated. Moreover, coumarin-6 loaded albuminated-PLGA-NPs were employed to evaluate the distribution and persistence of the NPs in the posterior segment. Results revealed that the bevacizumab vitreous concentration maintained above 500 ng mL(-1) for about 8 weeks and 3.3 times elevation was observed in the drug vitreous MRT compared with the control. According to coumarin-6 NP tests, fluorescence emissions in posterior tissues were observed for 56 days which confirmed the nanoparticles persistence in ocular tissues during the test span. Therefore our prepared formulation may offer improvements in treatment of eye posterior segment neovascularization.


Assuntos
Albuminas/química , Bevacizumab , Neovascularização de Coroide/tratamento farmacológico , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Animais , Bevacizumab/química , Bevacizumab/farmacocinética , Bevacizumab/farmacologia , Neovascularização de Coroide/patologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos
10.
Daru ; 23: 4, 2015 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-25616392

RESUMO

BACKGROUND: Comparison of long-term clinical results of two different pharmaceutical formulations used in corneal cross-linking (CXL) in keratoconus patients. METHODS: Sixty eyes of 60 keratoconus patients underwent CXL in two groups. We used riboflavin preparations from Sina Darou, Iran in group A, and Streuli Pharma, Switzerland in group B. Here we made inter-group comparison of changes in vision, refraction, Pentacam indices, corneal biomechanical indices, and endothelial cell count (ECC) 18 months after CXL. RESULTS: Since four patients were lost to follow-up, 56 eyes (28 eyes in each group) were compared. Mean improvement in uncorrected visual acuity (UCVA) was 0.31 ± 0.65 LogMAR (P=0.014) in group A and 0.24 ± 0.62 LogMAR (P=0.082) in group B. Best corrected visual acuity (BCVA) remained quite unchanged in both groups (P=0.774). Mean spherical refractive error reduced by 0.45 ± 1.15 diopter (D) (P=0.041) in group A and 0.27 ± 1.73 D (P=0.458) in group B (P=0.655). Cylinder error and spherical equivalent had a similar trend without any change. Max-K (P=0.006) and mean-K (P=0.044) decreased significantly more in group A compared to group B. The reduction in CCT was significantly more in group A than group B (P=0.004). Q-value was quite unchanged in both groups (P=0.704). The inter-group difference in CH reduction was borderline significant statistically (P=0.057). Changes in corneal resistance factor and endothelial cell count were not significantly different between two groups (P=0.117 and P=0.229). CONCLUSION: Clinical results of CXL with the domestic preparation of riboflavin are similar to that achieved with the Swiss made product in some aspects, and it is the preferred brand in some other aspects. This study will continue to report longer follow-up results. TRIAL REGISTRATION: IRCT201212034333N2.


Assuntos
Reagentes de Ligações Cruzadas/administração & dosagem , Ceratocone/tratamento farmacológico , Ceratocone/fisiopatologia , Riboflavina/administração & dosagem , Adulto , Química Farmacêutica , Reagentes de Ligações Cruzadas/uso terapêutico , Feminino , Seguimentos , Humanos , Irã (Geográfico) , Ceratocone/patologia , Masculino , Refração Ocular/efeitos dos fármacos , Riboflavina/uso terapêutico , Suíça , Resultado do Tratamento , Acuidade Visual/efeitos dos fármacos , Adulto Jovem
11.
Daru ; 22: 37, 2014 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-24713424

RESUMO

BACKGROUND: To compare the 6-month results of two formulations of Riboflavin provided by Sina Darou, Iran, and Uznach, Switzerland, in corneal collagen cross-linking (CXL) for keratoconus patients. FINDINGS: Considering the results of the previous study about the similarity of the formulations and the active ingredients of the two types of Riboflavin, they were used in the CXL procedure of 60 keratoconic eyes (30 eyes in each group). After 6 months, the mean improvement of UCVA (0.239), BCVA (0.707), and MRSE (0.513) did not differ significantly between the two groups. The mean decrease in max- K (0.731), mean- K (0.264), central corneal thickness (0.759), and Q-value (0.669) did not show any significant difference between the two groups. The two groups had no significant difference in endothelial cell count decrease (0.229). The Sina Darou formulation decreased corneal hysteresis more than the Swiss formulation (P = 0.057) but there were no significant differences in the mean decrease of corneal resistance factor between the two groups (P = 0.117). CONCLUSIONS: Based on the early results, the results of visual acuity, refraction, and corneal topography using Sina Darou and Uznach formulations of Riboflavin showed that both were effective in CXL. However, considering the relatively significant difference in corneal hysteresis changes between the two groups, this study will continue to report the long-term results.


Assuntos
Colágeno/metabolismo , Substância Própria/metabolismo , Reagentes de Ligações Cruzadas/administração & dosagem , Ceratocone/tratamento farmacológico , Fármacos Fotossensibilizantes/administração & dosagem , Riboflavina/administração & dosagem , Adulto , Química Farmacêutica , Topografia da Córnea , Reagentes de Ligações Cruzadas/uso terapêutico , Células Endoteliais/efeitos dos fármacos , Humanos , Irã (Geográfico) , Ceratocone/patologia , Masculino , Pessoa de Meia-Idade , Fármacos Fotossensibilizantes/uso terapêutico , Refração Ocular/fisiologia , Riboflavina/uso terapêutico , Suíça , Resultado do Tratamento , Acuidade Visual/fisiologia , Adulto Jovem
12.
Colloids Surf B Biointerfaces ; 116: 751-6, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24581925

RESUMO

The mesoporous glass-ceramic (GC) was employed as a carrier to investigate its capability for pharmaceutical applications. Piroxicam (PX) as a model drug was loaded in the GC by using of solvent evaporation technique. The physicochemical properties and morphology of the powders were evaluated employing X-ray powder diffractometry (XRPD), differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The drug adsorption isotherms were assessed as well. Drug release profiles were examined by fitting the data to the 10 common kinetic models. The specific surface area, Vm (the volume of the N2 adsorbed on the 1g of the GC when the monolayer is complete) and the average pore diameter of the GC powder before and after loading process were measured by the Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH) analysis benefiting N2 adsorption/desorption isotherms. The ideal loading of PX in the GC was 41.8%. The average pore diameter for the GC was determined to be about 10nm. The Freundlich model was found to be the best adsorption isotherm. Decrease of the GC specific surface area and Vm values were observed after loading process. Drug release data were best fitted to the Weibull model with the shape factor of 0.4-0.7 signifying the Fickian diffusion of PX from the GC. Accordingly, the GC could be considered as a suitable adsorbent to develop an oral drug delivery system.


Assuntos
Cerâmica/química , Fosfatos/química , Piroxicam/química , Físico-Química , Vidro/química , Tamanho da Partícula , Porosidade , Propriedades de Superfície
13.
Eur J Pharm Sci ; 50(3-4): 341-52, 2013 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-23933615

RESUMO

The rapidly growing applications of antibody-based therapeutics requires novel approaches to develop efficient drug delivery systems in which biodegradable polymeric nanoparticles are amongst the best candidates. In the present study bevacizumab loaded PLGA nanoparticles were formulated by water-in-oil-in-water emulsion method. Protein inactivation and aggregation are the major drawbacks of this technique. Therefore protective ability of various stabilizers was studied during entrapment process. Probable changes in VEGF165 binding capability of bevacizumab was assayed by ELISA which portrays the antibody's bio-efficiency. Probable breakage of bevacizumab and its secondary and tertiary structural integrity upon entrapment were analyzed by SDS-PAGE and circular dichroism spectroscopy, respectively. In vitro and ex vivo released bevacizumab from the prepared nanoparticles was also investigated. Results revealed that the protein interfacial adsorption is the foremost destabilizing factor in the double emulsion method and incorporation of appropriate concentrations of albumin could protect bevacizumab against entrapment stress. Ex vivo release results, in rabbit vitreous, indicated the ability of prepared nanoparticles in prolonged release of the active antibody. Consequently this approach was an attempt to achieve sustained release PLGA nanoparticle formulation with the aim of protecting integrity and performance of entrapped bevacizumab.


Assuntos
Inibidores da Angiogênese/química , Anticorpos Monoclonais Humanizados/química , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Albumina Sérica/química , Inibidores da Angiogênese/farmacologia , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Bevacizumab , Neovascularização de Coroide/tratamento farmacológico , Estabilidade de Medicamentos , Imunoglobulina G/imunologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos , Neovascularização Retiniana/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/metabolismo , Corpo Vítreo/metabolismo
14.
Invest Ophthalmol Vis Sci ; 54(8): 5520-6, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23833065

RESUMO

PURPOSE: Results of previous studies on the benefits of ocular drug delivery using polymeric mucoadhesive nanoparticles suggested longer presence and better penetration of nanoparticles, and, thus, increased effect and bioavailability of drugs entrapped in nanoparticles. In this study, a novel polymer, poly ß-amino ester, was used for the preparation of triamcinolone acetonide-loaded nanoparticles using a modified emulsification/solvent diffusion method. METHODS: Mucoadhesiveness studies, in vitro drug release, x-ray powder diffraction, differential scanning calorimetry, and scanning electron microscopy were used for physicochemical characterization of nanoparticles. Thirty-six hours after inducing uveitis by intravitreal injection of a lipopolysaccharide, sampling from the aqueous humor was done and inflammatory factors, such as cell, protein, nitric oxide, and prostaglandin E2, were compared. RESULTS: Nanoparticles with a mean size of 178 nm and drug loading of 5.3% were prepared and used for in vivo studies in rabbits with uveitis. Higher anti-inflammatory effect was observed for polymeric nanoparticles of triamcinolone acetonide compared with microparticles of prednisolone acetate and triamcinolone acetonide, and an equal effect compared with subconjunctival injection of triamcinolone acetonide in terms of inhibiting inflammation and inflammatory mediators. CONCLUSIONS: It can be concluded that polymeric nanoparticles of triamcinolone acetonide will provide as good an anti-inflammatory effect as the subconjunctival injection method and are better compared with other drug delivery systems.


Assuntos
Implantes Absorvíveis , Nanopartículas , Polímeros , Triancinolona Acetonida/administração & dosagem , Uveíte/tratamento farmacológico , Animais , Humor Aquoso/metabolismo , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/farmacocinética , Coelhos , Triancinolona Acetonida/farmacocinética , Uveíte/metabolismo , Corpo Vítreo/metabolismo
15.
Eur J Pharm Biopharm ; 84(1): 63-71, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23295645

RESUMO

The purpose of this work was to improve the efficacy of triamcinolone acetonide (TA) in the treatment of endotoxin-induced uveitis (EIU) using a polymeric nanoparticulate drug delivery system. Poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles were prepared using a modified emulsification/solvent diffusion method. Processing factors affecting loading and size were also studied. After physicochemical studies including in vitro release, X-ray powder diffraction, differential scanning calorimetry, and scanning electron microscopy, in vivo studies were conducted using nanoparticles sized 195 nm with 3.16% drug loading. Inflammatory factors such as flare, cell, and fibrin were studied in rabbit's eye over 96 h period, using laser flare meter and slit lamp examination. Inflammatory mediators such as NO, PGE2, cell, and protein were measured quantitatively 36 h after intravitreal injection of endotoxin in aqueous humor, and the therapeutic effects were compared in different groups. Results indicated statistically significant differences between the effect of nanoparticles in the treatment of EIU compared to microparticles of TA and prednisolone acetate (PA). There were no significant differences between the effects of TA injection and TA nanoparticles. In conclusion, sustain release biodegradable TA nanoparticles are potential new topical treatment options which can provide better patient compliance.


Assuntos
Nanopartículas/administração & dosagem , Polímeros/administração & dosagem , Triancinolona Acetonida/administração & dosagem , Uveíte/tratamento farmacológico , Animais , Humor Aquoso/efeitos dos fármacos , Humor Aquoso/metabolismo , Feminino , Nanopartículas/química , Tamanho da Partícula , Polímeros/química , Polímeros/farmacocinética , Coelhos , Distribuição Aleatória , Resultado do Tratamento , Triancinolona Acetonida/química , Triancinolona Acetonida/farmacocinética , Uveíte/metabolismo , Uveíte/patologia , Difração de Raios X
16.
Colloids Surf B Biointerfaces ; 81(2): 498-502, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20719477

RESUMO

Naproxen is a non-steroidal anti-inflammatory drug which can be used for the treatment of inflammatory disorders like uveitis and arthirit rheumatoid. The aim of the present study was to investigate the physicochemical characteristics of naproxen-PLGA nanoparticles. The nanoparticles of naproxen with PLGA were formulated using the solvent evaporation/extraction technique (the single emulsion technique). Several process parameters i.e., drug/polymer ratio, aqueous phase volume and speed of homogenization were considered with the aim of achieve optimal preparation conditions. The physicochemical characteristics of nanoparticles were studied applying particle size analysis, differential scanning calorimetry, X-ray crystallography, Fourier transform infrared spectroscopy and scanning electron microscopy. The release rate of naproxen from various drug/polymer nanoparticles was investigated as well. All the prepared formulations using PLGA resulted in nano-range size particles (352-571 nm) with spherical smooth morphology. The nanoparticles of naproxen-PLGA displayed lower crystallinity with no chemical interactions between the drug and polymer molecules. The nanoparticles exhibited the slower release of drug in comparison with the intact drug and the physical mixtures. According of these findings, formulation of the naproxen-PLGA nanoparticles was able to improve the physicochemical characteristics of the drug and possibly will increase the anti-inflammatory effects of drug following its ocular or intra-joint administration.


Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Ácido Láctico/química , Naproxeno/química , Ácido Poliglicólico/química , Anti-Inflamatórios não Esteroides/química , Físico-Química , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Difração de Pó , Propriedades de Superfície , Temperatura , Fatores de Tempo
17.
J Nat Med ; 62(4): 464-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18484154

RESUMO

Seven free-radical-scavenging phenolic compounds including five flavonoids, rutin (1), chrysoeriol 7-O-rutinoside (2), kaempferol 3-O-glucoside (3), chrysoeriol 7-O-glucoside (4) and naringenin (5), and two phenylethanoid glycosides, forsythoside B (6) and acteoside (7) were isolated from the methanol extract of the aerial parts of the Iranian medicinal plant Phlomis caucasica by reversed-phase preparative high-performance liquid chromatography (HPLC), and the structures of these compounds were elucidated by spectroscopic means. The free-radical-scavenging properties of 1-7 were assessed by 2,2-diphenyl-1-picryl hydrazyl (DPPH) assay. Among these compounds, forsythoside B (6) and acteoside (7) were found to be the most potent antioxidants with the RC(50) values of 4.97 and 4.27 microg/ml, respectively.


Assuntos
Sequestradores de Radicais Livres/farmacologia , Fenóis/farmacologia , Phlomis/química , Extratos Vegetais/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Compostos de Bifenilo , Cromatografia Líquida de Alta Pressão , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Sequestradores de Radicais Livres/isolamento & purificação , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Irã (Geográfico) , Medicina Tradicional , Fenóis/isolamento & purificação , Picratos , Componentes Aéreos da Planta , Análise Espectral
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...