Formulations with green clay for acne-prone skin: evaluation of rheology and sensory

Acne is an inflammatory skin condition that develops in pilosebaceous follicles, affecting mainly the onset of puberty. Among the numerous chemicals with dermatological and cosmetic purpose, traded and prescribed, raw materials of mineral origin have been often sought in formulations aimed at treating and / or preventing acne. This work aimed at the development of cosmetic preparations including green clay and sensory analysis of the formulations. Four formulations containing 2.5 % to 5 % green clay, in the presence or absence of dimethicone were prepared. The rheological behavior of the samples was analyzed at time 0, 24 hours, 30 days, 60 days and 90 days, using a cone and plate type rheometer (DVII + viscometer, Brookfiel). Sensory analyses of the formulations were also made. It can be concluded that all formulations exhibited pseudoplastic behavior and, through statistical analysis, it was found that there were no significant differences in acceptance between the formulations with or without dimethicone in the attributes of spreadability, stickiness, color and sensation after application. However, in regard to the attribute of odor, it was found that there was a greater acceptance in formulations to which dimethicone was added

UVA and UVB formulation phototoxicity in a three-dimensional human skin model: photodegradation effect

In vitro three-dimensional human skin models are an innovative alternative to evaluate cytotoxicity and phototoxicity in the cosmetic industry. The aim of this study was to use a skin model to evaluate the potential toxicity of sunscreen formulations with or without exposure to UV radiation. In addition, the toxicity of these formulations was evaluated after exposure to photodegradation. The results showed toxicity with all formulations/conditions tested, including the control formulation, compared to PBS. Cell viability of photodegraded formulations - prior to the phototoxicity radiation process - was higher, indicating that some formulation components were degraded into products with reduced toxicity. The results also indicated that avobenzone was more unstable/toxic than octyl p-methoxycinnamate under the same test conditions. The sunscreens and their formulations were shown to be toxic to skin model cells to some extent, even when not exposed to UV irradiation; however the biological role of this toxicity is unclear. This result shows the importance of testing sunscreen formulations in real in-use conditions. Finally, since we used an in vitro assay based on a human cell model, this non-invasive technique represents a suitable alternative to animal models for phototoxicity tests in general and could have application in screening new sunscreen products

Association Between Frequent Use of Makeup and Presence of Depressive Symptoms—Population-Based Observational Study, Including 2400 Participants

Abstract Introduction The increased prevalence of depression is a global phenomenon, with an estimated 320 million cases worldwide. In Brazil, the World Health Organization (WHO) estimated that there are about 12 million cases or more, mainly among adult women with lower socioeconomic status, leading to a high consumption of health resources. Studies suggest a positive association of measures related to appearance care on depressive symptoms, but usually with no objective methodology. This study aimed to estimate the prevalence of depressive symptoms in adult Brazilian women with lower purchasing power and to verify the association between the intensity of symptoms and the use of makeup. Methods A national sample of 2400 cases from all regions of the country, drawn randomly from an online panel representative of the Brazilian population, was studied using an online questionnaire accessible via computer or smartphone, from which the frequency of use of makeup was surveyed, and the Zung Depressive Self-Rating Scale was applied for the inventory of symptoms. Results A prevalence of 61.4% (0.59–0.63) of depressive symptoms was identified. The association between frequent use of makeup and a lower prevalence of cases with a Zung index suggestive of mild depression was confirmed. Association between frequent use of makeup and lower intensity of depressive symptoms was also identified among cases with a Zung index suggestive of absence of depression. Additionally, an association was identified between the habit of frequent use of makeup and higher economic class as well as the younger age group. Conclusion The results suggest the hypothesis that use of makeup may contribute both to a lower prevalence of mild depression and less expressive symptoms when index of absence of depression is observed

ZnO:SBA-15 Nanocomposites for potential use in sunscreen: Preparation, properties, human skin penetration and toxicity

Aim: We evaluated the effects of the incorporation of zinc oxide (ZnO) nanoparticles in a mesoporous matrix, aiming to improve the textural, structural and morphological properties and verify their safety so that they can be applied in sunscreen cosmetics. Materials and Methods: ZnO nano-particles were incorporated into an ordered mesoporous silica matrix known as Santa Barbara Amorphous-15 (SBA-15), using post-synthesis methodology. The resulting nanocomposites were characterized using X-ray diffraction, small angle X-ray scattering, N adsorption-desorption isotherms, Fourier transform infrared spectroscopy, scanning electron microscopy and predicted in vitro sun protector factor (SPF) estimation. Effectiveness and safety were evaluated by antimicrobial activity, in vitro cell toxicity and non-invasive multi-photon tomography with fluorescence lifetime imaging. Results: The structure of the nanocomposites was similar to that of SBA-15, with little perturbation caused by ZnO incorporation. Nanocomposites had an increased in vitro SPF, reduced cytotoxic activity and favourable antimicrobial properties compared to ZnO. ZnO:SBA-15 nanocomposites exhibited no measurable toxicity when applied to human skin in vivo. Conclusion: Due to their suitable physicochemical properties and improved safety compared to bare ZnO nanoparticles, the ZnO:SBA-15 nanocomposites show promise for use in cosmetic applications

Papain-cyclodextrin complexes as an intestinal permeation enhancer: Permeability and in vitro safety evaluation

Oral drug delivery is the main route for drugs administration. However, some drugs have poor permeability across the intestinal barrier. Papain has been widely used in pharmaceutical applications due to its debridement properties and the ability to promote skin permeation of drugs. It is known that papain complexation with cyclodextrins improves its biological stability. In this paper, the ability of the native papain-cyclodextrin complexes is shown be an oral permeation enhancer to furosemide, using a Caco-2 monolayer system to evaluate drug permeability and apparent permeability coefficient. Analysis of the in vitro cytotoxicity over CHO–K1, Hep G2 and Caco-2 cell lines and genotoxicity over CHO–K1 and Hep G2 cell lines were also performed. Papain-cyclodextrins complexes did not show any cytotoxicity above 31 μg/mL. No significant genotoxic damage was observed. Papain and cyclodextrin complexes induced almost 2.5-fold increase in furosemide permeation compared to controls, and maintenance of the paracellular integrity of the Caco-2 cells monolayer was confirmed. The papain complexes may be safely applied in pharmaceutical formulations, not only as a therapeutic agent but also as a strategic pharmaceutical adjuvant, promoting permeation of low oral permeability drugs

Deformable liposomes as enhancer of caffeine penetration through human skin in a Franz diffusion cell test

Objective: The permeation of hydrophilic molecules through the skin is still a challenge due to the barrier posed by stratum corneum, the outermost layer of the skin. Liposomes have frequently been used as carriers for different types of drugs and may also function as permeation enhancers. Propylene glycol has also been used as an edge activator in liposomes to increase the permeation. The aim of this work was to prepare liposomes containing an edge activator and loaded with caffeine to evaluate the potential of caffeine reaching the deeper layers in the skin.Methods: The formulations were prepared by a top‐down process using high‐pressure homogenization at 20000 psi for 10 minutes. They were characterized by size, polydispersity index (PI), zeta potential (ZP), pH, caffeine content, and encapsulation efficiency (EE%) on preparation (time zero) and after 30 days. Cytotoxicity of blank and loaded liposomes was assessed by MTT proliferation assay with a normal keratinocyte cell line (HaCaT). In vitro permeation tests were performed with human skin in Franz cells over 24 h, and caffeine concentration was determined in the skin surface, stratum corneum, dermo‐epidermal fraction and receptor medium by HPLC.Results: The caffeine liposomes with (DL‐Caf) or without propylene glycol (CL‐Caf) showed, respectively, mean size 94.5 and 95.4 nm, PI 0.48 and 0.42, ZP +1.3 and +18.1 mV and caffeine content of 78.57 and 80.13%. IC50\ua0values of caffeine in DL‐Caf (3.59 v/v %) and CL‐Caf (3.65 v/v %) were not significantly different from conventional blank liposome (3.27 v/v %). The DL‐Caf formulation presented the best capability to enhance the caffeine permeation through the skin, resulting 1.94 folds higher than caffeine solution. Furthermore, the caffeine flux from DL‐Caf was 1.56 and 3.05 folds higher than caffeine solution and CL‐Caf, respectively. On the other hand, CL‐Caf showed the lowest caffeine penetration revealing the importance of edge activator to aid hydrophilic drug penetration to all skin layers.Conclusion: The DL‐Caf formulation tested was able to improve the permeation of caffeine through the stratum corneum and dermo epidermal layers, suggesting that this delivery system may be effective for deep skin delivery of hydrophilic drugs

Os conflitos de licenciandos e o desenvolvimento profissional docente

Aprender a ensinar requer o desenvolvimento de atitudes, valores e conhecimentos próprios da docência por parte dos futuros professores, constituindo-se em um processo complexo a ser desencadeado pelas licenciaturas. Este estudo parte da premissa de que o licenciando vivencia conflitos ao longo de tal processo, os quais são possivelmente agravados pelas mudanças que a profissão docente tem sofrido, mudanças estas que, para alguns, configuram uma crise. Estudos anteriores, apoiados na teoria de Jean Piaget, indicam que a forma de perceber e resolver conflitos por professores em exercício é diferente entre os sujeitos, e que nem sempre o modo de lidar com as situações profissionais está relacionado ao tempo de carreira, mas sim a níveis de construção da docência. Assim, buscou-se saber se existem conflitos entre os professores em formação e se a forma de resolvê-los relaciona-se à aquisição da profissionalidade. Para tanto, licenciandos responderam a questionário e entrevista a partir de histórias hipotéticas envolvendo situações potencialmente geradoras de conflitos relativos a questões como autoridade docente, autonomia profissional e escolhas pedagógicas, entre outras. A compreensão da forma como os licenciandos interpretavam e enfrentavam - ou não - tais conflitos ofereceu indícios de níveis de construção da profissionalidade pelos sujeitos, mesmo que ainda não formados. Reconhecer a existência desses níveis abre caminhos para repensar a formação de professores nas licenciaturas, a fim de que se propiciem condições para que o licenciando desenvolva-se a um patamar superior de profissionalidade ainda durante a formação inicial.Learning to teach requires on the part of the future teachers the development of attitudes, values, and knowledges proper to the teaching activity, constituting a complex process that has to be put in motion by the licentiateship courses. The present study starts from the premise that the licentiateship student experiences conflicts during this process, which are possibly intensified by the changes that the teaching profession has undergone, changes that for some configure a crisis. Previous studies, based on Jean Piaget's theory, indicate that the ways to perceive and resolve conflicts vary among working teachers and that the way to deal with professional situations is not always related to career time, but to levels of construction of the teaching activity. Thus, the study sought to find out whether there are conflicts among teachers in preparation, and if the way to solve them can be related to the acquisition of professionalism. To that end, licentiateship students responded to a questionnaire and an interview based on hypothetical stories involving situations that were capable of producing conflicts related to issues such as teacher authority, professional autonomy, and pedagogical choices, among others. Understanding how the licentiateship students interpreted and dealt with - or failed to deal with - such conflicts offered clues as to the levels of construction of professionalism by the subjects, even if they had not yet concluded their courses. To recognize the existence of these levels opens up ways to rethink teacher education in licentiateships, so as to offer conditions for the students to develop further, into a higher level of professionalism, still during their initial training

Effect of flexing and massage on in vivo human skin penetration and toxicity of zinc oxide nanoparticles

Aim: We assessed the effects of flexing and massage on human skin penetration and toxicity of topically applied coated and uncoated zinc oxide nanoparticles (75 nm) in vivo. Materials & methods: Noninvasive multiphoton tomography with fluorescence lifetime imaging was used to evaluate the penetration of nanoparticles through the skin barrier and cellular apoptosis in the viable epidermis. Results: All nanoparticles applied to skin with flexing and massage were retained in the stratum corneum or skin furrows. No significant penetration into the viable epidermis was seen and no cellular toxicity was detected. Conclusion: Exposure of normal in vivo human skin to these nanoparticles under common in-use conditions of flexing or massage is not associated with significant adverse events