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High-risk solid tumors continue to pose a tremendous therapeutic challenge due to multidrug resistance. Biological mechanisms driving chemoresistance in high-risk primary and recurrent disease are distinct: in newly diagnosed patients, non-response to therapy is often associated with a higher level of tumor "stemness" paralleled by overexpression of the ABCG2 drug efflux pump, whereas in tumors relapsing after non-curative therapy, poor drug sensitivity is most commonly linked to the dysfunction of the tumor suppressor protein, p53. In this study, we used preclinical models of aggressive neuroblastoma featuring these characteristic mechanisms of primary and acquired drug resistance to experimentally evaluate a macromolecular prodrug of a structurally enhanced camptothecin analog, SN22, resisting ABCG2-mediated export, and glucuronidation. Together with extended tumor exposure to therapeutically effective drug levels via reversible conjugation to Pluronic F-108 (PF108), these features translated into rapid tumor regression and long-term survival in models of both ABCG2-overexpressing and p53-mutant high-risk neuroblastomas, in contrast to a marginal effect of the clinically used camptothecin derivative, irinotecan. Our results demonstrate that pharmacophore enhancement, increased tumor uptake, and optimally stable carrier-drug association integrated into the design of the hydrolytically activatable PF108-[SN22]2 have the potential to effectively combat multiple mechanisms governing chemoresistance in newly diagnosed (chemo-naïve) and recurrent forms of aggressive malignancies. As a macromolecular carrier-based delivery system exhibiting remarkable efficacy against two particularly challenging forms of high-risk neuroblastoma, PF108-[SN22]2 can pave the way to a robust and clinically viable therapeutic strategy urgently needed for patients with multidrug-resistant disease presently lacking effective treatment options.
Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Neuroblastoma/tratamento farmacológico , Pró-Fármacos/uso terapêutico , Inibidores da Topoisomerase I/uso terapêutico , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Camptotecina/análogos & derivados , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Nus , Camundongos SCID , Poloxâmero/química , Pró-Fármacos/administração & dosagem , Pró-Fármacos/química , Inibidores da Topoisomerase I/químicaRESUMO
Robust and predictive pre-clinical models of recalcitrant diabetic wounds are critical for advancing research efforts toward improving healing. Murine models have logistic and genetic benefits versus larger animals; however, native murine healing inadequately represents clinically recalcitrant wounds in humans. Furthermore, current humanization techniques employing devices, deleterious mutations or chemical agents each carry model-specific limitations. To better replicate human wounds in a mouse, we developed a novel wound-edge inversion (WEI) technique that mimics the architecture of epibole and mitigates contracture, epithelialization, and consequently wound closure. In this study, we evaluated the reliability and durability of the WEI model in wild-type and obese diabetic mice and compared to healing after (i) punch biopsy, (ii) mechanical/silicone stenting or (iii) exogenous oxidative stressors. In wild-type mice, WEI demonstrated favourable closure characteristics compared to both control and stented wounds, however, wounds progressed to closure by 4 weeks. In contrast, diabetic WEI wounds persisted for 6-10 weeks with reduced contracture and epithelialization. In both diabetic and wild-type mice, WEI sites demonstrated persistence of inflammatory populations, absence of epithelialization, and histologic presence of alpha-SMA positive granulation tissue when compared to controls. We conclude that the WEI technique is particularly valuable for modelling recalcitrant diabetic wounds with sustained inflammation and dysfunctional healing.
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Diabetes Mellitus Experimental , Cicatrização , Camundongos , Humanos , Animais , Diabetes Mellitus Experimental/patologia , Reprodutibilidade dos Testes , Pele/patologia , ReepitelizaçãoRESUMO
Food bioactive peptides are well recognized for their health benefits such as antimicrobial, antioxidant, and antihypertensive benefits, among others. Their drug-like behavior has led to their potential use in targeting skin-related aging factors like the inhibition of enzymes related with the skin-aging process. In this study, canary seed peptides (CSP) after simulated gastrointestinal digestion (<3 kDa) were fractioned by RP-HPLC and their enzyme-inhibition activity towards elastase and tyrosinase was evaluated in vitro. CSP inhibited elastase (IC50 = 6.2 mg/mL) and tyrosinase (IC50 = 6.1 mg/mL), while the hydrophobic fraction-VI (0.2 mg/mL) showed the highest inhibition towards elastase (93%) and tyrosinase (67%). The peptide fraction with the highest inhibition was further characterized by a multilevel in silico workflow, including physicochemical descriptor calculations, antioxidant activity predictions, and molecular dynamics-ensemble docking towards elastase and tyrosinase. To gain insights into the skin permeation process during molecular dynamics simulations, based on their docking scores, five peptides (GGWH, VPPH, EGLEPNHRVE, FLPH, and RPVNKYTPPQ) were identified to have favorable intermolecular interactions, such as hydrogen bonding of polar residues (W, H, and K) to lipid polar groups and 2-3 Å van der Waals close contact of hydrophobic aliphatic residues (P, V, and L). These interactions can play a critical role for the passive insertion of peptides into stratum corneum model skin-membranes, suggesting a promising application of CSP for skin-aging treatments.
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Monofenol Mono-Oxigenase , Phalaris , Simulação de Dinâmica Molecular , Elastase Pancreática , Sementes , Antioxidantes/farmacologiaRESUMO
Bisphenols such as bisphenol A (BPA), S (BPS), C (BPC), F (BPF), AF (BPAF), tetrabromobisphenol, nonylphenol, and octylphenol are plasticizers used worldwide to manufacture daily-use articles. Exposure to these compounds is related to many pathologies of public health importance, such as infertility. Using a protector compound against the reproductive toxicological effects of bisphenols is of scientific interest. Melatonin and vitamins have been tested, but the results are not conclusive. To this end, this systematic review and meta-analysis compared the response of reproductive variables to melatonin and vitamin administration as protectors against damage caused by bisphenols. We search for controlled studies of male rats exposed to bisphenols to induce alterations in reproduction, with at least one intervention group receiving melatonin or vitamins (B, C, or E). Also, molecular docking simulations were performed between the androgen (AR) and estrogen receptors (ER), melatonin, and vitamins. About 1234 records were initially found; finally, 13 studies were qualified for review and meta-analysis. Melatonin plus bisphenol improves sperm concentration and viability of sperm and increases testosterone serum levels compared with control groups; however, groups receiving vitamins plus bisphenols had lower sperm concentration, total testis weight, and testosterone serum levels than the control. In the docking analysis, vitamin E had the highest negative MolDock score, representing the best binding affinity with AR and ER, compared with other vitamins and melatonin in the docking. Our findings suggest that vitamins could act as an endocrine disruptor, and melatonin is most effective in protecting against the toxic effects of bisphenols.
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Disruptores Endócrinos , Melatonina , Masculino , Ratos , Animais , Melatonina/farmacologia , Vitaminas , Simulação de Acoplamento Molecular , Sêmen/metabolismo , Compostos Benzidrílicos/toxicidade , Compostos Benzidrílicos/química , Reprodução , Receptores de Estrogênio , Vitamina A , Vitamina K , Testosterona/metabolismo , Disruptores Endócrinos/toxicidade , Disruptores Endócrinos/químicaRESUMO
The term biopolymer refers to materials obtained by chemically modifying natural biological substances or producing them through biotechnological processes. They are biodegradable, biocompatible and non-toxic. Due to these advantages, biopolymers have wide applications in conventional cosmetics and new trends and have emerged as essential ingredients that function as rheological modifiers, emulsifiers, film-formers, moisturizers, hydrators, antimicrobials and, more recently, materials with metabolic activity on skin. Developing approaches that exploit these features is a challenge for formulating skin, hair and oral care products and dermatological formulations. This article presents an overview of the use of the principal biopolymers used in cosmetic formulations and describes their sources, recently derived structures, novel applications and safety aspects of the use of these molecules.
Le terme biopolymère fait référence aux matériaux obtenus par modification chimique des substances biologiques naturelles ou ceux qui surviennent des processus biotechnologiques. Ils sont biodégradables, biocompatibles, et non-toxiques. Du à leur avantages, les biopolymères ont de larges applications dans les cosmétiques conventionnels ainsi que dans les nouvelles tendances, et se placent comme des ingrédients essentiels qui peut être utilise comme modificateurs rhéologiques, émulsifiants, producteurs de films, humectants, hydratants, antimicrobiens, et, plus récemment, comme matériaux avec activité métabolique sur la peau. Le développement d'approches compte tenu de ces caractéristiques constitue un défi pour la création de produits de soins capillaires, dermatologiques et buccodentaires. Cet article présente une vision sur l'utilisation des principaux biopolymères dans les produits cosmétiques, et décrit leurs sources, leur structures dérivées, les nouvelles applications, ainsi que les aspects de sécurité lies à leur utilisation comme molécules cosmétiques.
Assuntos
Cosméticos , Biopolímeros/química , EmulsificantesRESUMO
BACKGROUND: Autologous fat grafting, although broadly indicated, is limited by unsatisfactory retention and often requires multiple procedures to achieve durable outcomes. Graft survival is strongly influenced by the magnitude and duration of post-engraftment ischemia. Calcitriol is a pleiotropic, safe nutrient with cell-specific influence on viability and metabolic flux. OBJECTIVES: Evaluate the efficacy of activated vitamin D3 (calcitriol) in improving grafting outcomes and examine its mechanisms. METHODS: Lipoaspirate was collected for ex vivo culture (7 unique donors), in vitro bioenergetic analysis (6 unique donors), and in vivo transplantation (5 unique donors). Ex vivo samples were incubated for up to 2 weeks before extraction of the stromal vascular fraction (SVF) for viability or flow cytometry. SVF was collected for Seahorse (Agilent; Santa Clara, CA) analysis of metabolic activity. Human endothelial cell lines were utilized for analyses of endothelial function. In vivo, samples were implanted into athymic mice with calcitriol treatment either (1) once locally or (2) 3 times weekly via intraperitoneal injection. Grafts were assessed photographically, volumetrically, and histologically at 1, 4, and 12 weeks. Hematoxylin and eosin (H&E), Sirius red, perilipin, HIF1α, and CD31 tests were performed. RESULTS: Calcitriol-treated lipoaspirate demonstrated dose-dependent increases in SVF viability and metabolic reserve during hypoxic stress. Calcitriol treatment enhanced endothelial mobility ex vivo and endothelial function in vitro. In vivo, calcitriol enhanced adipocyte viability, reduced fibrosis, and improved vascularity. Continuous calcitriol was sufficient to improve graft retention at 12 weeks (P < .05). CONCLUSIONS: Calcitriol increased fat graft retention in a xenograft model. Calcitriol has potential to be a simple, economical means of increasing fat graft retention and long-term outcomes.
Assuntos
Tecido Adiposo , Calcitriol , Camundongos , Animais , Humanos , Tecido Adiposo/transplante , Calcitriol/farmacologia , Colecalciferol/farmacologia , Xenoenxertos , Adipócitos/transplante , Modelos Animais de Doenças , Sobrevivência de EnxertoRESUMO
BACKGROUND: Emerging virus infections provoke health problems in people and animals, which generate social, and economic issues worldwide. This has spurred the search for new pharmacological strategies to confront them. SUMMARY: The purpose of this review is to draw the reader's attention to pharmacological evaluations of glycyrrhizic acid (GA) and its analogs on the broad range of viruses known in human and veterinary medicine. GA is the main water-soluble constituent extracted from the roots of plants from the genus Glycyrrhiza, commonly known as licorice root. It has long been used due to its broad spectrum of bioactivities, including anti-inflammatory, antiulcer, and antitumor properties. It has also been proposed as an antiviral agent. Medicines derived from GA are currently being used to combat acute and chronic hepatitis and herpes viruses. KEY MESSAGES: This review suggests that GA could be a new broad-spectrum antiviral due to its ability to inhibit DNA or RNA viruses both in vitro and in vivo. GA could be a potential drug for preventing and/or treating various viral diseases.
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Despite the use of intensive multimodality therapy, the majority of high-risk neuroblastoma (NB) patients do not survive. Without significant improvements in delivery strategies, anticancer agents used as a first-line treatment for high-risk tumors often fail to provide clinically meaningful results in the settings of disseminated, recurrent, or refractory disease. By enhancing pharmacological selectivity, favorably shifting biodistribution, strengthening tumor cell killing potency, and overcoming drug resistance, nanocarrier-mediated delivery of topoisomerase I inhibitors of the camptothecin family has the potential to dramatically improve treatment efficacy and minimize side effects. In this study, a structurally enhanced camptothecin analog, SN22, reversibly coupled with a redox-silent tocol derivative (tocopheryl oxamate) to allow its optimally stable encapsulation and controlled release from PEGylated sub-100 nm nanoparticles (NP), exhibited strong NB cell growth inhibitory activity, translating into rapid regression and durably suppressed regrowth of orthotopic, MYCN-amplified NB tumors. The robust antitumor effects and markedly extended survival achieved in preclinical models recapitulating different phases of high-risk disease (at diagnosis vs. at relapse with an acquired loss of p53 function after intensive multiagent chemotherapy) demonstrate remarkable potential of SN22 delivered in the form of a hydrolytically cleavable superhydrophobic prodrug encapsulated in biodegradable nanocarriers as an experimental strategy for treating refractory solid tumors in high-risk cancer patients.
Assuntos
Camptotecina/análogos & derivados , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Neuroblastoma/tratamento farmacológico , Pró-Fármacos/uso terapêutico , Tocoferóis/uso terapêutico , Camptotecina/química , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Neuroblastoma/patologia , Fatores de Risco , Análise de Sobrevida , Tocoferóis/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Consumers today demand the use of natural additives and preservatives in all fresh and processed foods, including meat and meat products. Meat, however, is highly susceptible to oxidation and microbial growth that cause rapid spoilage. Essential oils are natural preservatives used in meat and meat products. While they provide antioxidant and antimicrobial properties, they also present certain disadvantages, as their intense flavor can affect the sensory properties of meat, they are subject to degradation under certain environmental conditions, and have low solubility in water. Different methods of incorporation have been tested to address these issues. Solutions suggested to date include nanotechnological processes in which essential oils are encapsulated into a lipid or biopolymer matrix that reduces the required dose and allows the formation of modified release systems. This review focuses on recent studies on applications of nano-encapsulated essential oils as sources of natural preservation systems that prevent meat spoilage. The studies are critically analyzed considering their effectiveness in the nanostructuring of essential oils and improvements in the quality of meat and meat products by focusing on the control of oxidation reactions and microbial growth to increase food safety and ensure innocuity.
Assuntos
Anti-Infecciosos , Produtos da Carne , Óleos Voláteis , Óleos Voláteis/farmacologia , Conservantes de Alimentos/farmacologia , Carne/análise , Anti-Infecciosos/farmacologia , Conservação de Alimentos/métodosRESUMO
This paper analyses the changes on the maritime network before and after the Covid-19 outbreak. Using a large sample of vessel movements between ports, we show a decrease in the global maritime connectivity and significant differences between ports and inter-port links. Furthermore, we find that Covid-19 mitigation measures implemented by governments affected regional port hierarchies differently, with a reduction in port concentration in Europe and Africa and an increase in Asia and North America. Globally, very large ports and small but densely inter-connected ones resisted better to the crisis than the others, while small transshipment hubs and bridges appear to have been more negatively impacted. These findings have implications for the design of more resilient port strategies and transport policies by states and firms.
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Neurodegenerative disorders have been linked to the decrease of copper concentrations in different regions of the brain. Therefore, intake of micronutrient supplements could be a therapeutic alternative. Since the copper distribution profile has not been elucidated yet, the aim of this study was to characterize and to analyze the concentration profile of a single administration of copper gluconate to rats by two routes of administration. Male Wistar rats were divided into three groups. The control group received vehicle (n = 5), and the experimental groups received 79.5 mg/kg of copper orally (n = 4-6) or 0.64 mg/kg of copper intravenously. (n = 3-4). Blood, striatum, midbrain and liver samples were collected at different times. Copper concentrations were assessed using atomic absorption spectrophotometry. Copper concentration in samples from the control group were considered as baseline. The highest copper concentration in plasma was observed at 1.5 h after oral administration, while copper was quickly compartmentalized within the first hour after intravenous administration. The striatum evidenced a maximum metal concentration at 0.25 h for both routes of administration, however, the midbrain did not show any change. The highest concentration of the metal was held by the liver. The use of copper salts as replacement therapy should consider its rapid and discrete accumulation into the brain and the rapid and massive distribution of the metal into the liver for both oral and intravenous routes. Development of controlled-release pharmaceutical formulations may overcome the problems that the liver accumulation may imply, particularly, for hepatic copper toxicity.
Assuntos
Gluconatos/farmacocinética , Administração Oral , Animais , Relação Dose-Resposta a Droga , Gluconatos/administração & dosagem , Gluconatos/sangue , Injeções Intravenosas , Masculino , Ratos , Ratos Wistar , Distribuição TecidualRESUMO
Nanoparticles have shown overall beneficial effects in drug administration. Specifically, solid lipid nanoparticles (SLN) have emerged as an alternative to polymer-based systems. However, the oral administration of SLN, the first choice for conventional medications, has not been addressed due to the taboo surrounding the complicated transit that this delivery route entails. This review focuses on the encapsulation of drugs into SLN as a strategy for improving oral administration. Examples of applications of SLN to enhance the absorption and bioavailability of poorly-soluble drugs and protect acid-labile active molecules are discussed. This work also emphasizes the importance of developing SLN-based systems to treat health issues such as neurological diseases and cancer, and combat antibiotic resistance, three significant and increasingly common current public health problems. The review sections clarify how SLN can improve bioavailability, target therapeutic agents, and reduce side effects.
Assuntos
Administração Oral , Lipossomos/administração & dosagem , Sistemas de Liberação de Fármacos por Nanopartículas/administração & dosagem , Nanopartículas/administração & dosagem , Animais , Disponibilidade Biológica , Humanos , SolubilidadeRESUMO
In this study, a Venturi tube is proposed as an efficient static mixer incorporated into a continuous recirculation system for obtaining solid lipid nanoparticles (SLN) of monoolein. The device's operating principle consists of producing a turbulent flux in the throat of a Venturi tube. Taking advantage of this effect SLN of monoolein were obtained by rapid diffusion of the organic phase into the aqueous phase (stabilizer), causing lipid aggregation on the nanometric particles. The main aim of the present study was to evaluate the critical factors for obtaining the SLN of monoolein in order to control the independent variables of this methodology. A Box-Behnken design was used to study such independent variables (factors) as injection rate (X1), recirculation rate (X2), and stabilizer (X3) on the dependent variables; namely, process yield (Y1), particle size (Y2), polydispersity index (Y3) and zeta potential (Y4). The optimum operating conditions for preparing SLN were: injection rate, 1.6 mL/min; recirculation rate, 4.2 L/min; and stabilizer concentration, 1.0 w/v, with a value of D = 0.84. The predicted responses of the particle size were 212.0 nm, with a polydispersity index of 0.21, a zeta potential of -19.9 mV, and a process yield of 96.0%. Under the same operating condition, SLN formed with different lipids and stabilizers were obtained with nanometric size and zeta potential of â¼ -30.0 mV. Results show that the Venturi tube method is an innovative and versatile technique for preparing SLN of nanometric size with high process yields through a turbulent flow.
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Lipídeos , Nanopartículas , Excipientes , Lipossomos , Tamanho da PartículaRESUMO
The purpose of the study was to develop a novel, directly compressible, co-processed excipient capable of providing a controlled-release drug system for the pharmaceutical industry. A co-processed powder was formed by adsorption of solid lipid nanoparticles (SLN) as a controlled-release film onto a functional excipient, in this case, dicalcium phosphate dihydrate (DPD), for direct compression (Di-Tab®). The co-processed excipient has advantages: easy to implement; solvent-free; industrial scaling-up; good rheological and compressibility properties; and the capability to form an inert platform. Six different batches of Di-Tab®:SLN weight ratios were prepared (4:0.6, 3:0.6, 2:0.6, 1:0.6, 0.5:0.6, and 0.25:0.6). BCS class III ranitidine hydrochloride was selected as a drug model to evaluate the mixture's controlled-release capabilities. The co-processed excipients were characterized in terms of powder rheology and dissolution rate. The best Di-Tab®:SLN ratio proved to be 2:0.6, as it showed high functionality with good flow and compressibility properties (Carr Index = 16 ± 1, Hausner Index = 1.19 ± 0.04). This ratio could control release for up to 8 h, so it fits the ideal profile calculated based on biopharmaceutical data. The compressed systems obtained using this powder mixture behave as a matrix platform in which Fickian diffusion governs the release. The Higuchi model can explain their behavior.
Assuntos
Preparações de Ação Retardada/farmacologia , Excipientes/química , Lipídeos/química , Nanopartículas/química , Força Compressiva , Liberação Controlada de Fármacos , Nanopartículas/ultraestrutura , Tamanho da Partícula , Pós , Ranitidina/farmacologia , ReologiaRESUMO
The aim of the present study was to assess the expression of cytokines and FCεR1A receptor stimulated by Haemonchus placei larval excretory and secretory (ES) products associated with the pathogenesis in calves. Bovine peripheral blood mononuclear cells (PBMC) were stimulated in in vitro assays with H. placei L4 ES product at 8, 12, 16 and 24â¯h. ES products were collected in in vitro assays at 48â¯h with molecular weight of 72/60â¯kDa and isoelectric point of 7.2 pI. Specific IgG for infected and control calves, positive and negative, were employed to recognise H. placei larval ES products by indirect ELISA, showing a mean of 1.8, 0.83 and 0.28 OD, respectively, (pâ¯≤â¯0.001). The quantification of relative gene expression was performed using a set of cytokines (IL-2, IFNγ, TGFß, IL-4, IL-5, IL-6, IL-8, IL-10 and IL-13), FCεR1A receptor and housekeeping (GAPDH, ß-actin and ß-2-microglobulin) by RT-qPCR. An early increased expression, 2.2- to 3.4-fold change, of IL-2 (pâ¯≤â¯0.001), IL-5 and TGFß (pâ¯≥â¯0.05) was determined, followed by TGFß (30.7 and 14.14), IL-8 (102.8 and 1504.4) and IL-10 (60.4 and 1.7) (pâ¯≤â¯0.05) after 12 and 16â¯h, respectively, and reducing the expression level at 24â¯h. In addition, IL-6, IL-13 and FCεR1A receptor also displayed mild expression level, 2.1 - to 7.60-fold change, at 24â¯h (pâ¯≥â¯0.05). We conclude that ES products of 72/60â¯kDa collected in vitro from H. placei larvae are recognised by infected hosts and have the ability to induce diverse immune factors to modulate the nematode damage.
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Citocinas/metabolismo , Haemonchus/metabolismo , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Receptores de IgE/metabolismo , Animais , Bovinos , Proliferação de Células/efeitos dos fármacos , Citocinas/genética , Haemonchus/genética , Haemonchus/imunologia , Imunoglobulina G/metabolismo , Larva/genética , Larva/imunologia , Larva/metabolismo , Leucócitos Mononucleares/metabolismo , Masculino , RNA Mensageiro/metabolismo , Regulação para CimaRESUMO
The vagina is a region of administration with a high contact surface to obtain local or systemic effects. This anatomical area represents special interest for government health systems for different sexually transmitted infections. However, the chemical changes of the vagina, as well as its abundant mucus in continuous exchange, act as a barrier and a challenge for the development of new drugs. For these purposes, the development of new pharmaceutical forms based on nanoparticles has been shown to offer various advantages, such as bioadhesion, easy penetration of the mucosa, and controlled release, in addition to decreasing the adverse effects of conventional pharmaceutical forms. In order to obtain nanoparticles for vaginal administration, the use of polymers of natural and synthetic origin including biodegradable and non-biodegradable systems have gained great interest both in nanospheres and in nanocapsules. The main aim of this review is to provide an overview of the development of nanotechnology for vaginal drug release, analyzing the different compositions of polymeric nanoparticles, and emphasizing new trends in each of the sections presented. At the end of this review, a section analyzes the properties of the vehicles employed for the administration of nanoparticles and discusses how to take advantage of the properties that they offer. This review aims to be a reference guide for new formulators interested in the vaginal route.
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Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Polímeros/química , Administração Intravaginal , Feminino , HumanosRESUMO
Currently, nanotechnology represents an important tool and an efficient option for extending the shelf life of foods. Reducing particle size to nanometric scale gives materials distinct and improved properties compared to larger systems. For food applications, this technology allows the incorporation of hydrophilic and lipophilic substances with antimicrobial and antioxidant properties that can be released during storage periods to increase the shelf life of diverse products, including whole and fresh-cut fruits and vegetables, nuts, seeds, and cheese, among others. Edible coatings are usually prepared with natural polymers that are non-toxic, economical, and readily available. Nanosystems, in contrast, may also be prepared with biodegradable synthetic polymers, and liquid and solid lipids at room temperature. In this review, recent developments in the use of such nanosystems as nanoparticles, nanotubes, nanocomposites, and nanoemulsions, are discussed critically. The use of polymers as the support matrix for nanodispersions to form edible coatings for food preservation is also analyzed, but the central purpose of the article is to describe available information on nanosystems and their use in different food substrates to help formulators in their work.
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Materiais Biocompatíveis , Materiais Revestidos Biocompatíveis , Conservação de Alimentos , Conservantes de Alimentos , Nanotecnologia , Materiais Biocompatíveis/química , Biopolímeros , Materiais Revestidos Biocompatíveis/química , Conservantes de Alimentos/química , Humanos , Nanopartículas/químicaRESUMO
Nanocapsules (NCs) are submicron-sized core shell systems which present important advantages such as improvement of drug efficacy and bioavailability, prevention of drug degradation, and provision of controlled-release delivery. The available methods for NC production require expensive recovery and purification steps which compromised the morphology of NCs. Industrial applications of NCs have been avoided due to the aforementioned issues. In this study, we developed a new method based on a modified self-microemulsifying drug delivery system (SMEDDS) for in situ NCs production within the gastrointestinal tract. This new methodology does not require purification and recovery steps and can preserve the morphology and the functionality of NCs. The in situ formed NCs of Eudragit® RL PO were compared with nanospheres (NEs) in order to obtain evidence of their core-shell structure. NCs presented a spherical morphology with a size of 126.2 ± 13.1 nm, an ibuprofen encapsulation efficiency of 31.3% and a zeta-potential of 37.4 mV. Additionally, NC density and release profile (zero order) showed physical evidence of the feasibility of NCs in situ creation.
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Sistemas de Liberação de Medicamentos , Nanocápsulas , Administração Oral , Portadores de Fármacos , Composição de Medicamentos , Indústria Farmacêutica , Emulsões , Excipientes , Estudos de Viabilidade , Trato Gastrointestinal/metabolismo , Microscopia Eletrônica de Varredura , Tamanho da Partícula , PolímerosRESUMO
Polyglutamine (polyQ) diseases are a class of neurodegenerative disorders that cause cellular dysfunction and, eventually, neuronal death in specific regions of the brain. Neurodegeneration is linked to the misfolding and aggregation of expanded polyQ-containing proteins, and their inhibition is one of major therapeutic strategies used commonly. However, successful treatment has been limited to date because of the intrinsic properties of therapeutic agents (poor water solubility, low bioavailability, poor pharmacokinetic properties), and difficulty in crossing physiological barriers, including the blood-brain barrier (BBB). In order to solve these problems, nanoparticulate systems with dimensions of 1-1000 nm able to incorporate small and macromolecules with therapeutic value, to protect and deliver them directly to the brain, have recently been developed, but their use for targeting polyQ disease-mediated protein misfolding and aggregation remains scarce. This review provides an update of the polyQ protein aggregation process and the development of therapeutic strategies for halting it. The main features that a nanoparticulate system should possess in order to enhance brain delivery are discussed, as well as the different types of materials utilized to produce them. The final part of this review focuses on the potential application of nanoparticulate system strategies to improve the specific and efficient delivery of therapeutic agents to the brain for the treatment of polyQ diseases.
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Nanopartículas , Doenças Neurodegenerativas/tratamento farmacológico , Peptídeos , Animais , Barreira Hematoencefálica , HumanosRESUMO
Hypertrophic cardiomyopathy (HCM) is a cardiac disease, characterized by marked hypertrophy and genetic variability. HCM has been associated with sarcomere protein mutations, being cardiac beta-myosin (coded by the MYH7 gene) and myosin binding protein C (coded by the MYBPC3 gene) the most frequently affected proteins. As in Venezuela only the clinical analysis are performed in HCM patients, we decided to search for genetic variations in the MYH7 gene. Coding regions, including the junction exon-intron of the MYH7 gene, were studied in 58 HCM patients, whose samples were collected at the ASCARDIO Hospital (Barquisimeto, Lara state, Venezuela) and 106 control subjects from the ASCARDIO Hospital and the IVIC (Barquisimeto Lara state and Miranda, Venezuela, respectively). The blood samples were analyzed by genomic DNA isolation, followed by polymerase chain reaction and sequence analysis. The screening of the MYH7 gene revealed eight already reported polymorphic variants, as well as two intronic variations in these HCM patients. Neither any missense mutations nor other pathological mutations in the MYH7 gene were found in the HCM patients.