Glucocorticoid receptor-dependent therapeutic efficacy of tauroursodeoxycholic acid in preclinical models of spinocerebellar ataxia type 3.

Spinocerebellar ataxia type 3 (SCA3) is an adult-onset neurodegenerative disease caused by a polyglutamine expansion in the ataxin-3 (ATXN3) gene. No effective treatment is available for this disorder, other than symptom-directed approaches. Bile acids have shown therapeutic efficacy in neurodegenerative disease models. Here, we pinpointed tauroursodeoxycholic acid (TUDCA) as an efficient therapeutic, improving the motor and neuropathological phenotype of SCA3 nematode and mouse models. Surprisingly, transcriptomic and functional in vivo data showed that TUDCA acts in neuronal tissue through the glucocorticoid receptor (GR), but independently of its canonical receptor, the farnesoid X receptor (FXR). TUDCA was predicted to bind to the GR, in a similar fashion to corticosteroid molecules. GR levels were decreased in disease-affected brain regions, likely due to increased protein degradation as a consequence of ATXN3 dysfunction being restored by TUDCA treatment. Analysis of a SCA3 clinical cohort showed intriguing correlations between the peripheral expression of GR and the predicted age at disease onset in presymptomatic subjects and FKBP5 expression with disease progression, suggesting this pathway as a potential source of biomarkers for future study. We have established a novel in vivo mechanism for the neuroprotective effects of TUDCA in SCA3 and propose this readily available drug for clinical trials in SCA3 patients.

A Novel Genetic Variant in MBD5 Associated with Severe Epilepsy and Intellectual Disability: Potential Implications on Neural Primary Cilia.

Disruptions in the MBD5 gene have been linked with an array of clinical features such as global developmental delay, intellectual disability, autistic-like symptoms, and seizures, through unclear mechanisms. MBD5 haploinsufficiency has been associated with the disruption of primary cilium-related processes during early cortical development, and this has been reported in many neurodevelopmental disorders. In this study, we describe the clinical history of a 12-year-old child harboring a novel MBD5 rare variant and presenting psychomotor delay and seizures. To investigate the impact of MBD5 haploinsufficiency on neural primary cilia, we established a novel patient-derived cell line and used CRISPR-Cas9 technology to create an isogenic control. The patient-derived neural progenitor cells revealed a decrease in the length of primary cilia and in the total number of ciliated cells. This study paves the way to understanding the impact of MBD5 haploinsufficiency in brain development through its potential impact on neural primary cilia.

Exudative versus Nonexudative Age-Related Macular Degeneration: Physiopathology and Treatment Options.

Age-related macular degeneration (AMD) is an eye disease typically associated with the aging and can be classified into two types-namely, the exudative and the nonexudative AMD. Currently available treatments for exudative AMD use intravitreal injections, which are associated with high risk of infection that can lead to endophthalmitis, while no successful treatments yet exist for the nonexudative form of AMD. In addition to the pharmacologic therapies administered by intravitreal injection already approved by the Food and Drug Administration (FDA) in exudative AMD, there are some laser treatments approved that can be used in combination with the pharmacological therapies. In this review, we discuss the latest developments of treatment options for AMD. Relevant literature available from 1993 was used, which included original articles and reviews available in PubMed database and also information collected from Clinical Trials Gov website using "age-related macular degeneration" and "antiangiogenic therapies" as keywords. The clinical trials search was limited to ongoing trials from 2015 to date.

Evaluation of In Vitro Solar Protection Factor (SPF), Antioxidant Activity, and Cell Viability of Mixed Vegetable Extracts from Dirmophandra mollis Benth, Ginkgo biloba L., Ruta graveolens L., and Vitis vinífera L.

The aim of this study was to validate a HPLC method for the assay of flavonoids in extracts obtained from natural sources, i.e., from Dirmophandra mollis Benth, Ginkgo biloba L., Ruta graveolens L., and Vitis vinífera L. The potential sun protecting effect, antioxidant activity, and cell viability of the extracts were also determined. Individual extracts (obtained from each individual species) and a mixed extract (containing the four extracts) were analyzed by the validated HPLC method for the identification of flavonoids and quantification of rutin and quercetin. An in vitro cell viability study was carried out using the neutral red method. The in vitro sun protection factor was determined by spectral transmittance and in vitro antioxidant efficacy was evaluated against DPPH, ABTS, and AAPH radicals. The HPLC method used for the identification and quantification of flavonoids in extracts exhibited linearity, precision, accuracy, and robustness. Detection and quantification limits were, respectively, 2.881 ± 0.9 µg·mL-1 and 0.864 ± 0.9 µg·mL-1 for quercetin, and 30.09 ± 1 µg·mL-1 and 9.027 ± 1.1 µg·mL-1 for rutin. All extracts did not affect cell viability at the evaluated concentration range and exhibited a sun protection effect and antioxidant activity. Among the evaluated extracts, Ginkgo biloba L. and the mixed extract depicted the most expressive antioxidant activity. The mixed extract exhibited sunscreen protection against ultraviolet A (UVA) and ultraviolet B (UVB) and a critical wavelength of 372.7 ± 0.1. Our results translate the enhanced flavonoids' composition of the mixed extract, which may be a potential alternative over sunscreens and antioxidants in pharmaceutic/cosmetic formulations.

Flavonoid-Enriched Plant-Extract-Loaded Emulsion: A Novel Phytocosmetic Sunscreen Formulation with Antioxidant Properties.

The aim of this study was to develop a phytocosmetic sunscreen emulsion with antioxidant effect, containing a blend of flavonoid-enriched plant extracts. In vitro sun protection factor, antioxidant activity, skin irritation, photostability, cutaneous permeation, and retention of flavonoids were evaluated. Thermodynamically stable emulsions were obtained and tested for sensorial analysis after loading the blend of extracts. The selected emulsion was stable when stored at low temperatures (5 C), for which after 120 days the concentration of quercetin and rutin were above their limit of quantification, i.e., 2.8 ± 0.39 µg/mL and 30.39 ± 0.39 µg/mL, respectively. Spreadability, low rupture strength and adhesiveness were shown to be similar to a conventional topical product. Higher brittleness, pseudo-plastic, and viscoelastic behaviors were also recorded for the developed phytocosmetic sunscreen. The product presented a critical wavelength of 387.0 nm and ultraviolet rays A and B (UVA/UVB) rate of 0.78, confirming that the developed formulation shows capacity for UVA/UVB protection, protecting skin against damages caused by Ultraviolet (UV) radiation. Rutin was shown to permeate the skin barrier and was also quantified in the stratum corneum (3.27 ± 1.92 µg/mL) by tape stripping and retention test (114.68 ± 8.70 µg/mL). The developed flavonoid-enriched phytocosmetic was shown to be non-irritant to skin by an in vitro assay. Our results confirm the antioxidant activity, sun protection, and physical properties of the developed phytocosmetic for topical application.

Effect of Polysaccharide Sources on the Physicochemical Properties of Bromelain-Chitosan Nanoparticles.

Bromelain, a set of proteolytic enzymes potential pharmaceutical applications, was encapsulated in chitosan nanoparticles to enhance enzyme stability, and the effect of different chitosan sources was evaluated. Chitosan types (i.e., low molecular weight chitosan, chitosan oligosaccharide lactate, and chitosan from shrimp shells) produced nanoparticles with different physicochemical properties, however in all cases, particle size and zeta potential decreased, and polydispersity index increased after bromelain addition. Bromelain encapsulation was higher than 84% and 79% for protein content and enzymatic activity, respectively, with low molecular weight chitosan presenting the highest encapsulation efficiency. Nanoparticle suspension was also tested for accelerated stability and rheological behavior. For the chitosan-bromelain nanoparticles, an instability index below 0.3 was recorded and, in general, the loading of bromelain in chitosan nanoparticles decreased the cohesiveness of the final suspension.

Association of Platelet-Rich Plasma and Auto-Crosslinked Hyaluronic Acid Microparticles: Approach for Orthopedic Application.

Platelet-rich plasma (PRP) associated with high molecular weight hyaluronic acid (HA) has been clinically used for tissue regeneration in orthopedics. Despite the recognized beneficial clinical outcomes (e.g., early pain control, improvement of patients' functional limitation and longer-term effectiveness compared to PRP and HA alone in mild and moderate osteoarthritis treatments), its use is still challenging and controversial due to lack of standardization of association practical protocols. Moreover, most studies neglect the matrix structure, that generates the ultimate properties of the association among platelets, fibrin network and the microparticles. In the present work, we aimed to analyze the influence of the PRP/HA association with a controlled matrix structure on the stability, rheological behavior, release of growth factors and in vitro proliferation of human adipose-derived mesenchymal cells (h-AdMSCs). The attenuation of the negative charge of HA was also evaluated. Pure PRP (P-PRP) (i.e., plasma enriched with platelets and poor in leukocytes) was prepared by centrifugation and activated with serum and calcium chloride (AP-PRP). Autocrosslinked hyaluronic acid (AHA) was prepared by organocatalyzed auto-esterification and structured in microparticles (MPAHA) by shearing. The attenuation of the negative charge of MPAHA was performed with chitosan (CHT) by polyelectrolyte complexation yielding MPAHA-CHT. The results showed that microparticles (MPs) have viscoelastic properties, extrusion force and swelling ratio appropriate for injectable applications. The association of AP-PRP with the controlled structure of MPAHA and MPAHA-CHT formed a matrix composed of platelets and of a fibrin network with fibers around 160 nm located preferably on the surface of the MPs with an average diameter of 250 µm. Moreover, AP-PRP/MPAHA and AP-PRP/MPAHA-CHT associations were non-toxic and supported controlled growth factor (PDGF-AB and TGF-ß1) release and in vitro proliferation of h-AdMSC with a similar pattern to that of AP-PRP alone. The best h-AdMSC proliferation was obtained with the AP-PRP/MPAHA-CHT75:25 indicating that the charge attenuation improved the cell proliferation. Thus, the association of AP-PRP with the controlled structure of HA can be a valuable approach for orthopedic applications.

Development, Cytotoxicity and Eye Irritation Profile of a New Sunscreen Formulation Based on Benzophenone-3-poly(ε-caprolactone) Nanocapsules.

The objective of this work was to characterize the toxicological profile of a newly developed sunscreen formulation based on polymeric nanocapsules (NCs) loading benzophenone-3 (BZP3). NCs composed of poly(ε-caprolactone) carrot oil and Pluronic® F68 were produced by emulsification-diffusion method. Their mean particle size (Z-Ave) ranged from 280 to 420 nm, polydispersity index (PDI) was below 0.37, while zeta potential (ZP) reached about |+11 mV|. No cytotoxic effects were observed in L929 fibroblast cell line for the blank (i.e., non-loaded) NCs and BZP3-loaded NCs (BZP3-NCs). The semi-solid sunscreen formulation was stable over time (centrifugation testing) and exhibited non-Newtonian pseudoplastic behavior, which is typical of products for topical application onto the skin. The sun protection factor (SPF) value reached 8.84, when incorporating BZP3-NCs (SPF of 8.64) into the semi-solid formulation. A synergistic effect was also observed when combining the formulation ingredients of nanocapsules, i.e., SPF of carrot oil was 6.82, blank NCs was 6.84, and BZP3-loaded NCs was 8.64. From the hen's egg-chorioallantoic membrane test (HET-CAM) test, the non-irritation profile of the developed formulations could also be confirmed. The obtained results show a promising use of poly(ε-caprolactone) nanocapsules to be loaded with lipophilic sunscreens as benzophenone-3.

Evaluation of the Influence of Process Parameters on the Properties of Resveratrol-Loaded NLC Using 22 Full Factorial Design.

Resveratrol (RSV) is a natural antioxidant commonly found in grapes, berries, and nuts that has shown promising results in the treatment of a variety of degenerative and age-related diseases. Despite the proven beneficial results on reduction of reactive oxidant species (ROS) and on inflammatory process, RSV shows various limitations including low long-term stability, aqueous solubility, and bioavailability, restricting its applications in the medical-pharmaceutical area. To overcome these limitations, it has been applied in pharmaceutical formulations as nanostructured lipid carriers (NLC). Thus, the present study focuses on the optimization of the production process of NLC. NLC was produced by high shear homogenization (HSH) and ultrasound method (US) using Compritol® ATO C888 as solid lipid and Miglyol 812® as liquid lipid. In order to obtain an optimized formulation, we used a 22 full factorial design with triplicate of central point investigating the effects of the production process parameters; shear intensity and homogenization time, on the mean particle size (PS) and polydispersity index (PDI). Instability index, encapsulation efficiency, and production yield were also evaluated. As the PS and PDI values obtained with 6 min of shear at 19,000 rpm and 10 min of shear and 24,000 rpm were similar, the instability index (<0.1) was also used to select the optimal parameters. Based on the results of the experimental design and instability index, it was concluded that the shear rate of 19,000 rpm and the shear time of 6 min are the optimal parameters for RSV-loaded NLC production. Factorial design contributed therefore to optimize the variables of the NLC production process from a small number of experiments.

In vitro SPF and Photostability Assays of Emulsion Containing Nanoparticles with Vegetable Extracts Rich in Flavonoids.

The aim of study was to determine the in vitro sun protection factor (SPF) and the photostability profile of a topical formulation composed of nanoparticles loaded with vegetable extracts and to assess its physicochemical properties. Chitosan/tripolyphosphate (TPP) nanoparticles loaded with flavonoids-enriched vegetable extracts (Ginkgo biloba L., Dimorphandra mollis Benth, Ruta graveolens, and Vitis vinifera L.) were produced and characterized for their morphology, mean particle size, zeta potential, and encapsulation efficiency. A final topical formulation was obtained by dispersing chitosan/TPP nanoparticles in an o/w emulsion. Results showed that nanoparticles dispersion exhibited yellowish color, spherical shape, and uniform appearance. Extract-loaded chitosan/TPP nanoparticles showed a mean particle size of 557.11 ± 3.1 nm, polydispersity index of 0.39 ± 0.27, zeta potential of + 11.54 ± 2.1 mV, and encapsulation efficiency of 75.89% of rutin. The recorded texture parameters confirm that the developed formulation is appropriate for skin application. The SPF obtained was 2.3 ± 0.4, with a critical wavelength of 387.0 nm and 0.69 UVA/UVB ratio. The developed formulation exhibited photostability, allowing the release of flavonoids from nanoparticles while retaining rutin into the skin in a higher extension.

Impacto das práticas simuladas nos níveis de ansiedade dos estudantes de enfermagem / Impact of simulated practice on anxiety levels of nursing students

A simulação é uma excelente estratégia de ensino/aprendizagem, todavia pode desencadear ansiedade nos estudantes de enfermagem. Esta dissertação é constituída por duas partes, a primeira parte consiste na construção e validação de um instrumento de avaliação de ansiedade e a segunda parte consta a avaliação da ansiedade dos estudantes com as práticas simuladas. O objetivo geral deste estudo é analisar o impacto das práticas simuladas nos níveis de ansiedade dos estudantes de enfermagem. O objetivo específico, da primeira parte é construir e validar um instrumento de avaliação de ansiedade dos estudantes após as práticas simuladas (EAAPS). A segunda parte tem como objetivos específicos a comparação dos níveis de ansiedade em duas situações: antes e após as práticas simuladas de média fidelidade e alta-fidelidade e após as práticas simuladas com a média e a alta-fidelidade. Quanto ao tipo de estudo, na primeira parte utilizou-se uma abordagem metodológica e analítica; na segunda parte utilizou-se uma abordagem longitudinal, pré-experimental com um desenho antes e após e após com um grupo único. Relativamente à primeira parte, o instrumento com 25 itens foi validado por uma amostra de acidental/conveniência de 256 estudantes de enfermagem após as práticas simuladas. Realizou-se a validação do construto através da análise fatorial com a rotação ortogonal Varimax e a estimativa da consistência interna. A escala apresenta elevada correlação com praticamente todos os itens com o total da escala, com um alpha de 0,951. A análise de fidelidade dos três fatores apresenta uma consistência interna entre 0,794 e 0,939. A escala cumpre os requisitos de validade, revelando elevado potencial para utilização em investigação. Na segunda parte foram aplicadas duas escalas de avaliação da ansiedade (amostra acidental/conveniência), o Inventario de Ansiedade Traço-Estado (n = 223) e a EAAPS (n = 267). Verificou-se que as práticas simuladas contribuem para um aumento da ansiedade dos estudantes. Todavia a ansiedade resultante da fidelidade do simulador utilizado não apresentou resultados estatisticamente significativos.

Therapies for White Spot Lesions-A Systematic Review.

INTRODUCTION: The first sign of dental caries is denoted by white spot lesions (WSLs) which can be defined as a demineralization of the enamel surface and subsurface, although these lesions can be reversed and do not form cavities. The aim of this systematic review was investigate which remineralization agents are effective for the treatment of WSLs. MATERIALS AND METHODS: For this systematic review a literature search was conducted on Pubmed, Cochrane Library and ScienceDirect. RESULTS: The initial search resulted in 273 references. After elimination of duplicate articles, 236 references remained. After reading titles and abstracts, all non-relevant results were excluded, resulting in 45 potentially relevant studies. After reading the full text, 13 references were included. CONCLUSION: More studies are required for scientific evidence in order to reach a conclusion of the most suitable therapeutic method for the treatment of surface and subsurface demineralization of the enamel.