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1.
Molecules ; 26(9)2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-34063013

RESUMO

Marine organisms are able to produce a plethora of small molecules with novel chemical structures and potent biological properties, being a fertile source for discovery of pharmacologically active compounds, already with several marine-derived agents approved as drugs. Glioma is classified by the WHO as the most common and aggressive form of tumor on CNS. Currently, Temozolomide is the only chemotherapeutic option approved by the FDA even though having some limitations. This review presents, for the first time, a comprehensive overview of marine compounds described as anti-glioma agents in the last decade. Nearly fifty compounds were compiled in this document and organized accordingly to their marine sources. Highlights on the mechanism of action and ADME properties were included. Some of these marine compounds could be promising leads for the discovery of new therapeutic alternatives for glioma treatment.


Assuntos
Antineoplásicos/uso terapêutico , Organismos Aquáticos/química , Glioma/tratamento farmacológico , Bibliotecas de Moléculas Pequenas/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Glioma/patologia , Humanos , Nanotecnologia , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacocinética , Bibliotecas de Moléculas Pequenas/farmacologia
2.
Molecules ; 24(3)2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30678085

RESUMO

Following our previous work on the antitumor activity of acetylated flavonosides, a new acetylated xanthonoside, 3,6-bis(2,3,4,6-tetra-O-acetyl-ß-glucopyranosyl)xanthone (2), was synthesized and discovered as a potent inhibitor of tumor cell growth. The synthesis involved the glycosylation of 3,6-di-hydroxyxanthone (1) with acetobromo-α-d-glucose. Glycosylation with silver carbonate decreased the amount of glucose donor needed, comparative to the biphasic glycosylation. Xanthone 2 showed a potent anti-growth activity, with GI50 < 1 µM, in human cell lines of breast, lung, and glioblastoma cancers. Current treatment for invasive brain glioma is still inadequate and new agents against glioblastoma with high brain permeability are urgently needed. To overcome these issues, xanthone 2 was encapsulated in a liposome. To increase the well-known low stability of these drug carriers, a proliposome formulation was developed using the spray drying method. Both formulations were characterized and compared regarding three months stability and in vitro anti-growth activity. While the proliposome formulation showed significantly higher stability, it was at the expense of losing its biocompatibility as a drug carrier in higher concentrations. More importantly, the new xanthone 2 was still able to inhibit the growth of glioblastoma cells after liposome formulation.


Assuntos
Proliferação de Células/efeitos dos fármacos , Glioma/tratamento farmacológico , Lipossomos/farmacologia , Xantonas/farmacologia , Carbonatos/química , Linhagem Celular Tumoral , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Glioma/patologia , Glucose/química , Glicosilação/efeitos dos fármacos , Humanos , Lipossomos/síntese química , Lipossomos/química , Compostos de Prata/química , Xantonas/síntese química , Xantonas/química
3.
AIDS Care ; 28(1): 119-23, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26277905

RESUMO

Women account for 30% of all AIDS cases reported to the Health Ministry in Portugal and most infections are acquired through unprotected heterosexual sex with infected partners. This study analyzed socio-demographic and psychosocial predictors of consistent condom use and the role of education as a moderator variable among Portuguese women attending family planning clinics. A cross-sectional study using interviewer-administered fully structured questionnaires was conducted among 767 sexually active women (ages 18-65). Logistic regression analyses were used to explore the association between consistent condom use and the predictor variables. Overall, 78.7% of the women were inconsistent condom users. The results showed that consistent condom use was predicted by marital status (being not married), having greater perceptions of condom negotiation self-efficacy, having preparatory safer sexual behaviors, and not using condoms only when practicing abstinence. Living with a partner and having lack of risk perception significantly predicted inconsistent condom use. Less educated women were less likely to use condoms even when they perceive being at risk. The full model explained 53% of the variance in consistent condom use. This study emphasizes the need for implementing effective prevention interventions in this population showing the importance of taking education into consideration.


Assuntos
Preservativos/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Heterossexualidade , Estado Civil , Comportamento Sexual/psicologia , Adolescente , Adulto , Idoso , Estudos Transversais , Serviços de Planejamento Familiar , Feminino , Infecções por HIV/prevenção & controle , Infecções por HIV/psicologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Negociação , Portugal , Autoeficácia , Parceiros Sexuais , Infecções Sexualmente Transmissíveis/prevenção & controle , Fatores Socioeconômicos , Inquéritos e Questionários
4.
Mol Pharm ; 12(12): 4466-77, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26523837

RESUMO

Development of efficient and versatile drug delivery platforms to overcome the physical and biological challenges in cancer therapeutics is an area of great interest, and novel materials are actively sought for such applications. Recent strides in polymer science have led to a combinatorial approach for generating a library of materials with different functional identities that can be "mixed and matched" to attain desired characteristics of a delivery vector. We have applied the combinatorial design to chitosan (CS), where the polymer backbone has been modified with polyethylene glycol, epidermal growth factor receptor-binding peptide, and lipid derivatives of varying chain length to encapsulate hydrophobic drugs. Cisplatin, cis-([PtCl2(NH3)2]), is one of the most potent chemotherapy drugs broadly administered for cancer treatment. Cisplatin is a hydrophilic drug, and in order for it to be encapsulated in the developed nanosystems, it was modified with lipids of varying chain length. The library of four CS derivatives and six platinum derivatives was self-assembled in aqueous medium and evaluated for physicochemical characteristics and cytotoxic effects in platinum-sensitive and -resistant lung cancer cells. The results show that the lipid-modified platinate encapsulation into CS nanoparticles significantly improved cellular cytotoxicity of the drug. In this work, we have also reinforced the idea that CS is a multifaceted system that can be as successful in delivering small molecules as it has been as a nucleic acids carrier.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Quitosana/química , Receptores ErbB/metabolismo , Lipídeos/química , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas/química , Compostos Organoplatínicos/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Quitosana/administração & dosagem , Cisplatino/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Humanos , Lipídeos/administração & dosagem , Neoplasias Pulmonares/metabolismo , Nanopartículas/administração & dosagem , Compostos Organoplatínicos/química , Polietilenoglicóis/química , Bibliotecas de Moléculas Pequenas/administração & dosagem , Bibliotecas de Moléculas Pequenas/química
5.
Nanomedicine ; 11(7): 1621-31, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26049134

RESUMO

Pulmonary delivery of drugs for both local and systemic action has gained new attention over the last decades. In this work, different amphiphilic polymers (Soluplus®, Pluronic® F68, Pluronic® F108 and Pluronic® F127) were used to produce lyophilized formulations for inhalation of insulin. Development of stimuli-responsive, namely glucose-sensitive, formulations was also attempted with the addition of phenylboronic acid (PBA). Despite influencing the in vitro release of insulin from micelles, PBA did not confer glucose-sensitive properties to formulations. Lyophilized powders with aerodynamic diameter (<6 µm) compatible with good deposition in the lungs did not present significant in vitro toxicity for respiratory cell lines. Additionally, some formulations, in particular Pluronic® F127-based formulations, enhanced the permeation of insulin through pulmonary epithelial models and underwent minimal internalization by macrophages in vitro. Overall, formulations based on polymeric micelles presenting promising characteristics were developed for the delivery of insulin by inhalation. FROM THE CLINICAL EDITOR: The ability to deliver other systemic drugs via inhalation has received renewed interests in the clinical setting. This is especially true for drugs which usually require injections for delivery, like insulin. In this article, the authors investigated their previously developed amphiphilic polymers for inhalation of insulin in an in vitro model. The results should provide basis for future in vivo studies.


Assuntos
Química Farmacêutica , Sistemas de Liberação de Medicamentos , Insulina/administração & dosagem , Polímeros/administração & dosagem , Administração por Inalação , Ácidos Borônicos/administração & dosagem , Ácidos Borônicos/química , Técnicas de Cultura de Células , Glucose/metabolismo , Humanos , Insulina/química , Micelas , Permeabilidade/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Polímeros/química
6.
Pharm Biol ; 53(5): 642-52, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25489634

RESUMO

CONTEXT: Nanotechnology can be applied to deliver and protect antioxidants in order to control the oxidative stress phenomena in several chronic pathologies. Chitosan (CS) nanoparticles are biodegradable carriers that may protect antioxidants with potent biological activity such as rosmarinic acid (RA) in Salvia officinalis (sage) and Satureja montana (savory) extracts for safe and innovative therapies. OBJECTIVE: Development and characterization of CS nanoparticles as a stable and protective vehicle to deliver RA for medical applications using natural extracts as sage and savory. MATERIALS AND METHODS: Antioxidant-CS based nanoparticles were prepared by ionic gelation with sodium tripolyphosphate (TPP), at pH 5.8 with a mass ratio of 7:1 (CS:TPP), with a theoretical antioxidant-CS loading of 40-50%. The nanoparticles were then characterized by different methods such as photon correlation spectroscopy, laser Doppler anemometry, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR), high-performance liquid chromatographic (HPLC), association efficiency, and antioxidant activity. RESULTS AND DISCUSSION: Individual and small sizing nanoparticles, around 300 nm, were obtained. SEM confirmed smooth and spherical nanoparticles after freeze-drying. No chemical interactions were found between antioxidants and CS, after encapsulation, by DSC and FTIR. The association efficiency was 51.2% for RA (with 40% loading) and 96.1 and 98.2% for sage and savory nanoparticles, respectively (both with 50% loading). Antioxidant activity values were higher than 0.0348 eq [Asc. Ac.] g/L/g extract and 0.4251 µmol/eq Trolox/g extract. CONCLUSION: The extracts under study are promising vehicles for RA drug delivery in CS nanocarriers.


Assuntos
Quitosana/administração & dosagem , Cinamatos/administração & dosagem , Depsídeos/administração & dosagem , Sistemas de Liberação de Medicamentos , Nanopartículas/administração & dosagem , Extratos Vegetais/administração & dosagem , Salvia officinalis , Satureja , Quitosana/química , Cinamatos/química , Depsídeos/química , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Tamanho da Partícula , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Ácido Rosmarínico
7.
Mol Pharm ; 11(10): 3515-27, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25256346

RESUMO

RNA interference has emerged as a powerful strategy in cancer therapy because it allows silencing of specific genes associated with tumor progression and resistance. Mad2 is an essential mitotic checkpoint component required for accurate chromosome segregation during mitosis, and its complete abolition leads to cell death. We have developed an epidermal growth factor receptor (EGFR)-targeted chitosan system for silencing the Mad2 gene as a strategy to efficiently induce cell death in EGFR overexpressing human A549 non-small cell lung cancer cells. Control and EGFR-targeted chitosan nanoparticles loaded with small interfering RNAs (siRNAs) against Mad2 were formulated and characterized for size, charge, morphology, and encapsulation efficiency. Qualitative and quantitative intracellular uptake studies by confocal imaging and flow cytometry, respectively, showed time-dependent enhanced and selective intracellular internalization of EGFR-targeted nanoparticles compared to nontargeted system. Targeted nanoparticles showed nearly complete depletion of Mad2 expression in A549 cells contrasting with the partial depletion in the nontargeted system. Accordingly, Mad2-silencing-induced apoptotic cell death was confirmed by cytotoxicity assay and flow cytometry. Our results demonstrate that EGFR-targeted chitosan loaded with Mad2 siRNAs is a potent delivery system for selective killing of cancer cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Quitosana/química , Receptores ErbB/metabolismo , Proteínas Mad2/genética , Nanopartículas/química , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Citometria de Fluxo , Inativação Gênica/fisiologia , Humanos , Proteínas Mad2/fisiologia
8.
ACS Pharmacol Transl Sci ; 7(5): 1650-1663, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38751616

RESUMO

Type 1 diabetes (T1D) is characterized by insufficient insulin secretion due to ß-cell loss. Despite exogenous insulin administration being a lifesaving treatment, many patients still experience severe glycemic lability. For these patients, a ß-cell replacement strategy through pancreas or pancreatic islet transplantation is the most physiological approach. However, donors' scarcity and the need for lifelong immunosuppressive therapy pose some challenges. This study proposes an innovative biomimetic pancreas, comprising ß- and α-cells differentiated from human induced pluripotent stem cells (hiPSCs) embedded in a biofunctional matrix with glucose-responsive nanoparticles (NPs) encapsulating a glucagon-like peptide 1 (GLP-1) analogue, which aims to enhance the glucose responsiveness of differentiated ß-cells. Herein, glucose-sensitive pH-responsive NPs encapsulating exenatide or semaglutide showed an average size of 145 nm, with 40% association efficiency for exenatide-loaded NPs and 55% for semaglutide-loaded NPs. Both peptides maintained their secondary structure after in vitro release and showed a similar effect on INS-1E cells' insulin secretion. hiPSCs were differentiated into ß- and α-cells, and insulin-positive cells were obtained (82%), despite low glucose responsiveness, as well as glucagon-positive cells (17.5%). The transplantation of the developed system in diabetic mice showed promising outcomes since there was an increase in the survival rate of those animals. Moreover, diabetic mice transplanted with cells and exenatide showed a decrease in their glucose levels. Overall, the biomimetic pancreas developed in this work showed improvements in diabetic mice survival rate, paving the way for new cellular therapies for T1D that explore the synergy of nanomedicines and stem cell-based approaches.

9.
Brain Sci ; 14(1)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38248297

RESUMO

Glioblastoma (GBM) is a primary malignant tumor of the central nervous system responsible for the most deaths among patients with primary brain tumors. Current therapies for GBM are not effective, with the average survival of GBM patients after diagnosis being limited to a few months. Chemotherapy is difficult in this case due to the heterogeneity of GBM and the high efficacy of the blood-brain barrier, which makes drug absorption into the brain extremely difficult. In a previous study, 3',4',3,4,5-trimethoxychalcone (MB) showed antiproliferative and anti-invasion activities toward GBM cells. Polymersomes (PMs) are an attractive, new type of nanoparticle for drug administration, due to their high stability, enhanced circulation time, biodegradability, and sustained drug release. In the present study, different MB formulations, PEG2000-PCL and PEG5000-PCL, were synthesized, characterized, and compared in terms of 14-day stability and in vitro cytotoxicity (hCMEC/D3 and U-373 MG).

10.
Life (Basel) ; 14(1)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38255746

RESUMO

Glioblastoma (GBM) is the most common and deadly primary malignant brain tumor. Current therapies are insufficient, and survival for individuals diagnosed with GBM is limited to a few months. New GBM treatments are urgent. Polymeric nanoparticles (PNs) can increase the circulation time of a drug in the brain capillaries. Polymersomes (PMs) are PNs that have been described as having attractive characteristics, mainly due to their stability, prolonged circulation period, biodegradability, their ability to sustain the release of drugs, and the possibility of surface functionalization. In this work, a poly(ethylene glycol)-ε-caprolactone (PEG-PCL) copolymer was synthesized and PMs were prepared and loaded with an hydrolytic instable compound, previously synthesized by our research team, the 3,6-bis(2,3,4,6-tetra-O-acetyl-ß-glucopyranosyl)xanthone (XGAc), with promising cytotoxicity on glioblastoma cells (U-373 MG) but also on healthy cerebral endothelial cells (hCMEC/D3). The prepared PMs were spherical particles with uniform morphology and similar sizes (mean diameter of 200 nm) and were stable in aqueous suspension. The encapsulation of XGAc in PMs (80% encapsulation efficacy) protected the healthy endothelial cells from the cytotoxic effects of this compound, while maintaining cytotoxicity for the glioblastoma cell line U-373 MG. Our studies also showed that the prepared PMs can efficiently release XGAc at intratumoral pHs.

11.
Phytochem Anal ; 24(6): 638-44, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23716364

RESUMO

INTRODUCTION: Sage and savoury (Salvia sp. and Satureja montana, respectively) are plants used in traditional medicine. The quality control of their herbal formulations is of paramount concern to guarantee the expected biological activity of their anti-oxidant compounds. OBJECTIVE: To establish a simple and effective high-performance liquid chromatographic (HPLC) method to evaluate simultaneously quercetin and rosmarinic acid, in a pure form, in natural extracts (sage and savoury), and encapsulated into chitosan nanoparticles. METHODS: Chromatography was performed on an RP C18 -column, in a gradient mode with a mobile phase comprising methanol:formic acid:water 92.5:2.5:5 (v/v) at a flow rate of 0.75 mL/min and at wavelength of 280 nm. RESULTS: The method was specific, linear in the range of 0.05-1 mg/mL (R(2) = 1.00), precise at the intraday and interday levels, accurate (recovery rate 90.5 ± 0.6%), and robust to changes in equipment conditions. CONCLUSION: The method established was effective for quercetin and rosmarinic acid characterisation in natural extracts and in chitosan nanoparticles, allowing the loading capacity determination, the association efficiency as well as the in vitro release.


Assuntos
Cinamatos/análise , Depsídeos/análise , Extratos Vegetais/química , Plantas Medicinais/química , Quercetina/análise , Salvia officinalis/química , Satureja/química , Quitosana/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Nanopartículas/análise , Nanopartículas/ultraestrutura , Ácido Rosmarínico
12.
Adv Drug Deliv Rev ; 199: 114969, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37348678

RESUMO

Nystatin is an antifungal molecule with a remarkable yet squandered versatility. In this review, its mechanism of action is explored, along with its extensive action spectrum and toxicity. A multitude of methodologies to tackle the drug's physical and chemical hurdles are outlined along with some proven-effective strategies to increase its activity and/or decrease its toxicity. A separate detailed section focused on micro and nanotechnology solutions addresses new drug delivery systems made of polymeric, metallic or lipid materials. Although the topical route depicts greater representativeness amongst these formulations, the intravenous, dental, oral, vaginal and inhalation routes are also mentioned. The unsuccessful previous attempts at developing parenteral formulations of nystatin or even the withdrawal of a nystatin-loaded multilamellar liposome should not divert research away from this drug. In fact, the interest in nystatin ought to be reawakened with the ongoing clinical trials on the promising nystatin-like genetically engineered derivate BSG005.


Assuntos
Antifúngicos , Nistatina , Humanos , Antifúngicos/uso terapêutico , Antifúngicos/farmacologia , Nistatina/farmacologia , Nistatina/uso terapêutico , Lipossomos , Sistemas de Liberação de Medicamentos , Polímeros
13.
Pharmaceuticals (Basel) ; 16(12)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38139773

RESUMO

Leishmaniasis is a neglected tropical disease that affects millions of people around the world. Available therapy causes severe side effects, has unacceptable prices for some specific formulations, and the existence of drug-resistant parasites limits the use of the currently available arsenal of antiparasitic drugs. Therefore, natural products serve as one of the main sources to develop new and effective alternative drugs against leishmaniasis. In this sense, the present study evaluated the potential of the triterpene Lupeol (Lu) entrapped in nanostructured lipid carriers (NLCs) for the treatment of experimental visceral leishmaniasis. The therapeutic efficacy of Lu or Lu entrapped in NLC (Lu-NLC) was investigated in golden hamsters infected with Leishmania (Leishmania) infantum. Lu-NLC presented a mean particle size of 265.3 ± 4.6 nm, a polydispersity index of <0.25 and a zeta potential of -37.2 ± 0.84 mV; the efficacy of encapsulation was 84.04 ± 0.57%. Studies on hamsters showed that Lu-NLC (5 mg/kg) administered intraperitoneally for 10 consecutive days caused a reduction of 99.9% in the number of parasites in the spleen and liver compared to the untreated infected control. On the contrary, Lu-treated animals (5 mg/kg) had 94.4 and 90.2% less parasites in the spleen and liver, respectively, than the infected group. Additionally, a significant preservation of splenic and hepatic tissues was observed in animals treated with Lu-NLC or Lu. Furthermore, Lu-NLC-treated animals produced high levels of anti-Leishmania IgG2 isotype. These data indicate that NLC potentialized Lu efficacy in experimental visceral leishmaniasis. This work suggests that Lu and nanoformulations carrying this compound may be considered as an important tool to be included in the alternative therapy of leishmaniasis.

14.
J Liposome Res ; 22(1): 1-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21548711

RESUMO

Zanthoxylum tinguassuiba essential oil (ZtEO) contains α-bisabolol, a known antiglioma sesquiterpene, among other potentially active substances. Medical applications of this essential oil require advances in the design of distinctive carriers due to its low water solubility and easy degradation by heat, light, and oxygen. The aim of this work was to evaluate enhancement in oxidative stability and the ability to reduce glioblastoma cell viability of ZtEO loaded into liposomes. Multi- and unilamellar vesicles were prepared to carry ZtEO. By using thermal analysis, it was observed that thermal-oxidative stability of the liposomal ZtEO was enhanced, when compared to its free form. Liposomal ZtEO also presented significant apoptotic-inducing activity for glioma cells. These results show that liposomal systems carrying ZtEO may be a potential alternative for gliobastoma treatment.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Glioblastoma/tratamento farmacológico , Lipossomos/química , Óleos Voláteis/farmacologia , Temperatura , Zanthoxylum/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estabilidade de Medicamentos , Glioblastoma/patologia , Estrutura Molecular , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Oxirredução , Componentes Aéreos da Planta/química , Solubilidade , Relação Estrutura-Atividade
15.
Mater Sci Eng C Mater Biol Appl ; 118: 111413, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33255015

RESUMO

Oromucosal films and tablets were developed as multifunctional biomaterials for the treatment of oral mucositis. These are intended to function as a hybrid, performing as a controlled drug delivery system and as a wound-dressing device. The dosage forms are precursors for in loco hydrogels that are activated by the saliva. An anti-inflammatory and anesthetic activity is attained from budesonide tripartite polymeric nanoparticles and lidocaine, while the polymeric network allows the protection and cicatrization of the wound. Different biomaterials and blends were investigated, focusing on the capacity to retain and resist on-site, as well as achieve a long-lasting controlled release. As the limiting factor, the choice was made according to the films' results. A polymer mix of Methocel™ K100M and Carbopol® (974P, EDT 2020, or Ultrez 10) blends were used. Overall, regrading critical factors, Carbopol® increased films' elasticity and flexibility, mucoadhesion, and the strength of the hydrogels, while higher concentrations led to thicker, more opaque, and lower strain resistance products. Whereas 974P and Ultrez 10 performed similarly, EDT 2020 led to uniformity problems and weaker films, hydrogels and bioadhesion. The optimized products were enhanced with sodium hyaluronate and drug-loaded for further characterization. Concerning the dosage form, the films' hydrogels were more resilient, while the tablets had higher mucoadhesiveness and longer swelling. Although through different networks and mechanisms, both dosage forms and grades revealed similar release profiles. A Case II time-evolving stereoselectivity for the 22R and 22S budesonide epimers was found, and Fickian-diffusion for lidocaine. Ultimately, the developed formulations show great potential to be used in OM management. Both of the selected grades at 0.6% displayed excellent performance, while Ultrez 10 can be preferable for the films' production due to its lower viscosity before neutralization and higher after activation. Where the tablets are easier to produce and offer better adhesion, the films are more customizable post-production and have higher rheological performance for wound-dressing.


Assuntos
Hidrogéis , Estomatite , Bandagens , Sistemas de Liberação de Medicamentos , Humanos , Comprimidos
16.
Carbohydr Polym ; 252: 116978, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33183580

RESUMO

This work proposes the development and characterization of solid lipid nanoparticles (SLNs) loaded with rifampicin (RIF) aiming to enhance mucoadhesion of the SLNs and consequently internalization by the alveolar macrophages (AMs). The lipid nanoparticles (NPs) were characterized and the results showed that the NPs obtained present a spherical or a starry shape with diameter around 250-500 nm, a monodisperse population, with zeta potential between -31 mV for uncoated SLNs and +33 mV for coated SLNs. The drug EE was approximately 90 % and the loading capacity (LC) 4.5 %. The SLNs coated with chitosan by the association method (aC-SLNs) show an effective mucoadhesive profile, verified by the turdimetry and surface loading method, corroborated with the cellular assays. The presence of chitosan in the aC-SLNs promotes higher mucoadhesive properties to the NPs and permeability in A549, suggesting that the safe aC-SLNs-RIF can be used as a promising drug delivery system for improving tuberculosis treatment.


Assuntos
Antibióticos Antituberculose/administração & dosagem , Quitosana/química , Portadores de Fármacos/química , Lipídeos/química , Macrófagos Alveolares/efeitos dos fármacos , Nanopartículas/química , Rifampina/administração & dosagem , Células A549 , Liberação Controlada de Fármacos , Humanos , Tamanho da Partícula , Tuberculose/tratamento farmacológico
17.
Pharmaceutics ; 13(6)2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34205283

RESUMO

Ursolic acid, a triterpene produced by plants, displayed leishmanicidal activity in vitro and in vivo; however, the low solubility of this triterpene limits its efficacy. To increase the activity of ursolic acid (UA), this triterpene was entrapped in nanostructured lipid carriers (UA-NLC), physical-chemical parameters were estimated, the toxicity was assayed in healthy golden hamsters, and the efficacy of UA-NLC was studied in experimental visceral leishmanisis. UA-NLC exhibited a spherical shape with a smooth surface with a size of 266 nm. UA-NLC displayed low polydispersity (PDI = 0.18) and good colloidal stability (-29.26 mV). Hamsters treated with UA-NLC did not present morphological changes in visceral organs, and the levels of AST, ALT, urea and creatinine were normal. Animals infected with Leishmania (Leishmania) infantum and treated with UA-NLC showed lower parasitism than the infected controls, animals treated with UA or Amphotericin B (AmB). The therapeutic activity of UA-NLC was associated with the increase in a protective immune response, and it was associated with a high degree of spleen and liver preservation, and the normalization of hepatic and renal functions. These data indicate that the use of lipid nanoparticles as UA carriers can be an interesting strategy for the treatment of leishmaniasis.

18.
Pharmaceuticals (Basel) ; 13(9)2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32942693

RESUMO

The high incidence of fungal infections has become a worrisome public health issue, having been aggravated by an increase in host predisposition factors. Despite all the drugs available on the market to treat these diseases, their efficiency is questionable, and their side effects cannot be neglected. Bearing that in mind, it is of upmost importance to synthetize new and innovative carriers for these medicines not only to fight emerging fungal infections but also to avert the increase in drug-resistant strains. Although it has revealed to be a difficult job, new nano-based drug delivery systems and even new cellular targets and compounds with antifungal potential are now being investigated. This article will provide a summary of the state-of-the-art strategies that have been studied in order to improve antifungal therapy and reduce adverse effects of conventional drugs. The bidirectional relationship between Mycology and Nanotechnology will be also explained. Furthermore, the article will focus on new compounds from the marine environment which have a proven antifungal potential and may act as platforms to discover drug-like characteristics, highlighting the challenges of the translation of these natural compounds into the clinical pipeline.

19.
Biomed Chromatogr ; 23(9): 966-72, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19353738

RESUMO

A reversed-phase high performance liquid chromatography method has been developed and validated for determination and quantitation of the natural sesquiterpene (-)-alpha-bisabolol. Furthermore the application of the method was done by characterization of chitosan milispheres and liposomes entrapping Zanthoxylum tingoassuiba essential oil, which contains appreciable amount of (-)-alpha-bisabolol. A reversed-phase C(18) column and gradient elution was used with the mobile phase composed of (A) acetonitrile-water-phosphoric acid (19:80:1) and (B) acetonitrile. The eluent was pumped at a flow rate of 0.8 mL/min with UV detection at 200 nm. In the range 0.02-0.64 mg/mL the assay showed good linearity (R(2 )= 0.9999) and specificity for successful identification and quantitation of (-)-alpha-bisabolol in the essential oil without interfering peaks. The method also showed good reproducibility, demonstrating inter-day and intra-day precision based on relative standard deviation values (up to 3.03%), accuracy (mean recovery of 100.69% +/- 1.05%) and low values of detection and quantitation limits (0.0005 and 0.0016 mg/mL, respectively). The method was also robust for showing a recovery of 98.81% under a change of solvent in standard solutions. The suitability of the method was demonstrated by the successful determination of association efficiency of the (-)-alpha-bisabolol in chitosan milispheres and liposomes.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Sesquiterpenos/análise , Quitosana/química , Modelos Lineares , Lipossomos/química , Sesquiterpenos Monocíclicos , Óleos Voláteis/química , Extratos Vegetais/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Zanthoxylum/química
20.
J Interpers Violence ; 34(17): 3614-3636, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-27677950

RESUMO

This study examined if abuse during childhood, rape in adulthood, and loss of resources predict a woman's probability of reporting symptoms of posttraumatic stress disorder (PTSD), and whether resource loss moderates the association between reporting childhood abuse and PTSD symptoms. The sample included 767 women and was collected in publicly funded primary-care settings. Women who reported having been abused during childhood also reported more resource loss, more acute PTSD symptoms, and having suffered more adult rape than those who reported no childhood abuse. Hierarchical logistic regression yielded a two-variable additive model in which child abuse and adult rape predict the probability of reporting or not any PTSD symptoms, explaining 59.7% of the variance. Women abused as children were 1 to 2 times more likely to report PTSD symptoms, with sexual abuse during childhood contributing most strongly to this result. Similarly, women reporting adult rape were almost twice as likely to report symptoms of PTSD as those not reporting it. Resource loss was unexpectedly not among the predictors but a moderation analysis showed that such loss moderated the association between child abuse and current PTSD symptoms, with resource loss increasing the number and severity of PTSD symptoms in women who also reported childhood abuse. The findings highlight the importance of early assessment and intervention in providing mental health care to abused, neglected, and impoverished women to help them prevent and reverse resource loss and revictimization.


Assuntos
Sobreviventes Adultos de Maus-Tratos Infantis/psicologia , Mulheres Maltratadas/psicologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Saúde da Mulher/estatística & dados numéricos , Adulto , Mulheres Maltratadas/estatística & dados numéricos , Comorbidade , Feminino , Humanos , Modelos Logísticos , Estupro/psicologia , Apoio Social , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Adulto Jovem
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