Avaliação do comportamento das fibras colágenas periodontais durante a progressão da periodontite experimental em ratos / Evaluation of the behaviour of periodontal collagen fibers during the progression of experimental periodontitis in rats

Introdução: A periodontite é uma doença infecto-inflamatória, resultante da disbiose microbiana e da resposta do hospedeiro, que leva à destruição dos tecidos de suporte dentário, inclusive das fibras colágenas periodontais, podendo culminar na perda do elemento dental. Objetivo: Avaliar o comportamento das fibras colágenas periodontais durante a progressão da periodontite experimental induzida em ratos. Material e método: Doze ratos Wistar foram distribuídos nos grupos: Controle (C), Periodontite Experimental 14-dias (PE-14d), Periodontite Experimental 21-dias (PE-21d) e Periodontite Experimental 42-dias (PE-42d). No dia 0, os animais do grupo C foram eutanasiados. Neste mesmo dia, os animais remanescentes foram submetidos à instalação de uma ligadura de algodão ao redor do primeiro molar inferior esquerdo para indução da periodontite experimental. Tais animais foram eutanasiados aos 14 (PE-14d), 21 (PE-21d) e 42 (PE-42d) dias após a instalação da ligadura. Executou-se o processamento histológico das hemimandíbulas e as secções foram submetidas à reação histoquímica pelo vermelho picro-sirius. A análise qualitativa descritiva foi realizada sob microscopia de luz polarizada, na região de furca dental, evidenciando as fibras do ligamento periodontal. Resultado: O grupo C exibiu feixes espessos e orientados de fibras colágenas maduras, condizentes com aspecto de normalidade. Os grupos com periodontite experimental exibiram desestruturação tecidual severa, com fibras colágenas imaturas e de menor espessura, sendo tais condições mais exacerbadas nos grupos PE-14d e PE-21d. Conclusão: As fases iniciais da periodontite apresentam caráter agudo e, portanto, resultam na rápida destruição dos tecidos periodontais de suporte, prejudicando potencialmente a fibrilogênese e a reestruturação do colágeno no ligamento periodontal.

Introduction: Periodontitis is an infectious-inflammatory disease resulting from microbial dysbiosis and host response that leads to the destruction of tooth support tissues, including periodontal collagen fibers, which may culminate in tooth loss. Objective: To evaluate the behavior of periodontal collagen fibers during the progression of induced experimental periodontitis in rats. Material and method: Twelve Wistar rats were distributed into groups: Control (C), 14-days Experimental Periodontitis (PE-14d), 21-days Experimental Periodontitis (PE-21d) and 42-days Experimental Periodontitis (PE-42d). At day 0, the animals of group C were euthanized. At the same day, the remaining animals were submitted to the installation of a cotton ligature around the lower left first molar for the induction of experimental periodontitis. The animals were euthanized at 14 (PE-14d), 21 (PE-21d) and 42 (PE-42d) days after the installation of ligature. Histological processing of the hemi-mandibles was performed and the sections underwent histochemical reaction using picro-sirius red. The descriptive qualitative analysis was performed under polarized light microscopy, in the dental furcation region, evidencing the fibers of the periodontal ligament. Result: Group C exhibited thick and oriented bundles of mature collagen fibers, consistent with a normal appearance. The groups with experimental periodontitis exhibited severe tissue disruption, with immature and thinner collagen fibers, with such conditions being more exacerbated in the PE-14d and PE-21d groups. Conclusion: The early stages of periodontitis present acute response, and therefore result in rapid destruction of periodontal support tissues and potentially impair fibrillogenesis and collagen restructuring in the periodontal ligament.

Pesquisa de sujidade em produtos derivados do tomate por meio de microscopia óptica de luz polarizada / Study of subjects and strange substances in tomato products derived from polarized light optical microscopy

A microscopia alimentar é uma técnica utilizada no apoio ao controle da qualidade do alimento. Por meio desse estudo é possível verificar a qualidade do produto alimentar e as condições higiênico-sanitárias empregadas no processo de fabricação, armazenamento e distribuição por meio da busca por matérias estranhas. O processamento da polpa do tomate pode originar diversos produtos, tais como: sucos, molhos, purês e ketchup. A cadeia agroindustrial do tomate está entre as mais importantes no âmbito do agronegócio brasileiro. Dessa forma é importante o estudo da qualidade microscópica na busca por sujidades nesses alimentos dentre esses o extrato e o ketchup. Constatou-se o cuidado dos fabricantes de lançarem produtos no mercado com qualidades satisfatórias, acarretando também no zelo de não quererem denegrir sua imagem com produtos fora do padrão da legislação e contaminado.

Método químico simplificado de desmineralización del esmalte dental humano / Simplified chemical method of demineralization in human dental enamel

Introducción: Se requieren métodos experimentales abreviados para simular las lesiones de desmineralización temprana de forma controlada y reproducible. Objetivo: Realizar una evaluación in vitro de un método simple de desmineralización incipiente del esmalte. Métodos: Estudio experimental aleatorizado con doble diseño factorial de réplicas. Se seleccionaron 12 terceros molares de sujetos humanos saludables para su desmineralización en solución de ácido láctico racémico. Las muestras se distribuyeron aleatoriamente: Grupo 1 (G1) (n= 6) ácido láctico a pH 2,4 y Grupo 2 (G2) (n= 6) ácido láctico a pH 5,4. A continuación, cada grupo se subdividió (n = 2) para evaluar el efecto de las soluciones a tres tiempos de exposición (7, 15 y 30 días) a 37 °C. La evaluación se llevó a cabo con estereomicroscopios, equipo de radiografía digital con un software de análisis digital de imágenes y microscopía de polarización. Se formuló una integración de los índices de respuesta y se realizó un ANOVA. Resultados: Los hallazgos visuales, radiográficos e histológicos mostraron que en el G1 en los tiempos 1 a 3, la desmineralización se caracterizó por una gran pérdida de la integridad del esmalte (80 por ciento a 100 por ciento). Visualmente, el G2 a los 7 días mostró opacidad y pérdida de brillo (16 por ciento) con preservación de la estructura superficial del esmalte. Conclusiones: Se demuestra que el empleo de ácido láctico durante 7 días a pH 5,4 produce una lesión clínica, radiográfica e histológica similar a una lesión temprana del esmalte(AU)

Introduction: Abridged experimental methods are required to simulate early demineralizing lesions in a controlled and reproducible way. Objective: Perform an in vitro evaluation of a simple method of incipient enamel demineralization. Methods: Randomized experimental study with a double factorial replication design. Twelve third molars from healthy human subjects were selected for demineralization in a racemic lactic acid solution. Samples were then distributed randomly: Group 1 (G1) (n= 6) lactic acid at pH 2.4 and Group 2 (G2) (n= 6) lactic acid at pH 5.4. Each group was then subdivided (n = 2) to evaluate the effect of the solutions at three exposure times (7, 15 and 30 days) at 37°C. The evaluation used stereomicroscopes, a digital x-rays apparatus with software for the digital analysis of images, and polarization microscopy. An integration of the response indices was formulated and ANOVA was performed. Results: Visual, radiographic and histological findings showed that G1 at time 1 through 3 displayed demineralization characterized by extensive loss (80 percent to 100 percent) of enamel integrity. Visually, G2 at 7 days exhibited opacity and loss of brightness (16 percent), with preservation of the surface structure of the enamel. Conclusions: It was shown that employing lactic acid for 7 days at pH 5.4 develops a clinical, radiographic and histological injury similar to an early enamel lesion(AU)

Hypertension affects the biocompatibility and biomineralization of MTA, High-plasticity MTA, and Biodentine®

Abstract This study evaluated the effect of hypertension on tissue response and biomineralization capacity of white Mineral Trioxide Aggregate (MTA), High-plasticity MTA (MTA HP), and Biodentine® (BDT) in rats. Polyethylene tubes filled with MTA, MTA HP, BDT, and the control group (empty tubes) were placed into the dorsal subcutaneous tissue of 32 male rats (16 normotensive (NT) and 16 hypertensive rats - 8 per group). After 7 and 30 days, the polyethylene tubes surrounded by connective tissue were removed, fixed, and embedded in histological resin. The mean number of inflammatory cells was estimated in HE-stained sections, biomineralization was quantified as area (µm2) by Kossa (VK) staining, and examination by polarized light (LP) microscopy was performed. The differences amongst the groups were analyzed statistically by the Mann-Whitney or Student's t test, according to Shapiro-Wilk test of normality (p < 0.05). The inflammatory responses to all materials were greater in hypertensive rats than in NT rats (p < 0.05). Positive VK staining in MTA and BDT were more pronounced in NT rats at 7 and 30 days (p < 0.05). Birefringent structures in LP for MTA, MTA HP, and BDT were more pronounced in NT rats at 7 days (p<0.05). In rats, hypertension was able to increase inflammatory infiltrate and decrease biomineralization of the tested materials.

Remineralizing effect of commercial fluoride varnishes on artificial enamel lesions

Abstract: The aim of this study was to evaluate soluble and insoluble fluoride concentrations in commercial varnishes, and their remineralization effect on artificial caries enamel lesions using surface and cross-sectional microhardness evaluations. Forty bovine enamel blocks were separated into four groups (n=10): control (no treatment), Enamelast (Ultradent Products), Duraphat (Colgate-Palmolive) and Clinpro White Varnish (3M ESPE). Surface enamel microhardness evaluations were obtained, artificial enamel caries lesions were developed by dynamic pH-cycling, and the varnishes were then applied every 6 days, after which the enamel blocks were submitted to dynamic remineralization by pH cycles. After removal of the varnishes, the enamel surfaces were reassessed for microhardness. The blocks were sectioned longitudinally, and cross-sectional microhardness measurements were performed at different surface depths (up to 300 μm depth). Polarized light microscopy images (PLMI) were made to analyze subsurface caries lesions. The fluoride concentration in whole (soluble and insoluble fluoride) and centrifuged (soluble fluoride) varnishes was determined using an extraction method with acetone. The data were analyzed to evaluate the surface microhardness, making adjustments for generalized linear models. There was a significant decrease in enamel surface microhardness after performing all the treatments (p<0.0001). Enamelast and Duraphat showed significantly higher enamel microhardness values than the control and the Clinpro groups (p = 0.0002). Microhardness loss percentage was significantly lower for Enamelast (p = 0.071; One-way ANOVA). PLMI showed that subsurface caries lesions were not remineralized with the varnish treatments. No significant differences in the in-depth microhardness levels (p = 0.7536; ANOVA) were observed among the treatments. Enamelast presented higher soluble and insoluble fluoride concentrations than the other varnishes (p < 0.0001; Kruskal-Wallis and Dunn tests). Enamelast and Duraphat varnishes promoted enamel surface remineralization, but no varnish remineralized the subsurface lesion body. Although insoluble and soluble fluoride concentration values did not correspond to those declared by the manufacturer, Enamelast presented higher fluoride concentration than the others.

Evaluation of dermal collagen stained with picrosirius red and examined under polarized light microscopy

Abstract: The special picrosirius red staining highlights the natural birefringence of collagen fibers when exposed to polarized light. The results from birefringence allow to evaluate the organization of the collagen fibers in the tissues. The authors intend to elucidate all steps to obtain and capture images of histological sections stained with picrosirius red and evaluated under polarized light microscopy, as well as possible artefacts that may occur.

Carcinoma basocelular. Un reto actual para el dermatólogo / Basal cell carcinoma. An actual challenge for the dermatologist

RESUMEN El carcinoma basocelular es un tumor maligno de origen epitelial, su crecimiento es lento y rara vez metastiza. Este puede producir destrucción local y comprometer extensas áreas de tejido, cartílago y hueso. Existen variantes clínicas e histológicas y constituye el cáncer más frecuente en humanos y su incidencia está en aumento. Se realizó una revisión para exponer los aspectos esenciales sobre factores predisponentes, formas clínicas y diagnóstico, así como las opciones terapéuticas en esta entidad. Se desarrolló una búsqueda en la Biblioteca Virtual de Infomed y Google. Fueron revisados veinticinco trabajos científicos sin limitación de año y país, de los cuales quince pertenecen a los últimos 5 años. El carcinoma basocelular se considera de origen multifactorial, el carcinógeno más importante es la luz ultravioleta. La forma clínica más frecuente es la variedad nodular y la distribución es en cara y cuello. La elección del tratamiento dependerá del tamaño de la lesión, la localización, la edad y estado general del paciente. A pesar de tener baja malignidad y mortalidad, puede ocasionar destrucción y deformidad y repercutir en la vida de los pacientes. El dominio de los factores de riesgo, los elementos para el diagnóstico precoz y las opciones terapéuticas son indispensable para elegir la conducta adecuada frente a la enfermedad y promover cambios en el estilo de vida, que favorezcan la prevención y disminuyan la morbilidad por esta causa (AU).

ABSTRACT Basal cell Carcinoma (BCC) is an epidermal malignant tumor, it has a slow growth and seldom metastases. It can produce local destruction and compromise big tissue areas, cartilage and bone. There are clinical and histological presentations. It is one of the most common cancer in humans and its incidence is increasing. This project’s goal is to expose the essential aspects about the predisposal factors, clinic presentations and diagnoses as well as this disorder’s therapeutic options.This study was made from different bibliographical revisions. The research was developed on Infomed Database and Google. Twenty five Scientific studies were researched without country and/or timeline limit, from whom fifteen belongs to the last 5 years. BCC is considered to have a multifactorial origin, whose most important carcinogen is the ultraviolet light. The most frequent clinical presentation is the nodular and the most common distribution is face and neck. The treatment choice depends on the tumor size, its distribution and the patient’s age and current state. Although it is a low malignancy and low-death rate neoplasia, it can cause tissue destruction and affect patient’s social life. The management of the risk factors, the elements for the early diagnosis and the therapeutic options are indispensable to choose the adequate behavior for the disorder and promote life style changes that favor the prevention and lower the morbidity rate (AU).

Dermatoscopia para establecer márgenes quirúrgicos mínimos en la resección de carcinomas basocelulares / Dermoscopy for establishing the minimal surgical margins in basal cells carcinoma resection

Introducción: el carcinoma basocelular es la forma más común de cáncer de piel y el proceder quirúrgico es la elección para su tratamiento. Aparece más frecuente en áreas visibles o fotoexpuestas, por lo que en ocasiones, con el fin de preservar tejidos su resección es insuficiente; o por el contrario si se amplían a los márgenes establecidos, pudieran generar secuelas cicatrizales. La dermatoscopía es una técnica de fácil aplicación que permite previamente la visualización de los límites reales del tumor para así obtener márgenes quirúrgicos no comprometidos de menor tamaño que evitan posteriores deformidades estéticas. Objetivos: determinar la utilidad de la dermatoscopía para obtener márgenes quirúrgicos mínimos, libres de carcinomas basocelulares en cara y cuello, con posterior comprobación histológica. Materiales y Métodos: estudio observacional, descriptivo, en Hospital " Comandante Faustino Pérez Hernández" de la ciudad de Matanzas, a 21 pacientes, con diagnóstico clínico y dermatoscópico de carcinoma basocelular. Se les estableció mínimo margen quirúrgico a través de la dermatoscopía y posterior a ello, se comprobó histológicamente si los bordes de incisión estaban comprometidos o no. Resultados: el 95,5 % de los informes histopatológicos revelaron que las lesiones fueron bien resecadas. Conclusiones: el establecimiento dermatoscópico de un mínimo margen quirúrgico antes de la excéresis, constituye un método confiable para la obtención de lesiones bien resecadas, y disminuyen así las secuelas deformantes que provocan las cicatrices de las grandes incisiones en lesiones de cara y cuello (AU).

Introduction: the basal cell carcinoma is the most common form of skin cancer and the surgical procedure is the election for its treatment. It appears more frequently in visible or photo exposed areas, therefore, occasionally its resection is insufficient with the aim of preserving tissues, or because if it reaches the established margins it could generate scar sequels. Dermoscopy is an easily applicable technique allowing the previous visualization of the real limits of the tumor for obtaining surgical, noncompromised margins of less size that avoid subsequent esthetic deformities. Objectives: to determine the usefulness of dermoscopy for obtaining minimal surgical margins, free of basal cell carcinomas in the face and neck, with following histologic verification. Materials and Methods: observational, descriptive study carried out in the Hospital "Comandante Faustino Pérez Hernandez" of Matanzas, in 21 patients with clinical and dermoscopic of basal cell carcinoma. Through dermoscopy the minimal surgical margin was established and after that, it was checked histologically if the incision borders were compromised or not. Results: 95.5 % of the histopathological reports showed that the lesions were correctly resected. Conclusions: the dermoscopical establishment of a minimal surgical margin before the excision, is a reliable method for getting good resected lesions; that way, the deforming sequels caused by the scars of large incisions in lesions of the face and neck are reduced. (AU)

Duodenal amyloidosis secondary to ulcerative colitis

Amyloidosis is defined as the extracellular deposition of non-branching fibrils composed of a variety of serum-protein precursors. Secondary amyloidosis is associated with several chronic inflammatory conditions, such as rheumatologic or intestinal diseases, familial Mediterranean fever, or chronic infectious diseases, such as tuberculosis. Although the association of amyloidosis with inflammatory bowel disease is known, amyloidosis secondary to ulcerative colitis (UC) is rare. A 36-year-old male patient with a 15-year history of UC presented with nausea, vomiting, and abdominal pain. He had been treated with infliximab for 6 years. At the time of admission, he had been undergoing treatment with mesalazine and adalimumab since the preceding 5 months. Esophagogastroduodenoscopy showed mucosal erythema, edema, and erosions with geographic ulcers at the 2nd and 3rd portions of the duodenum. Duodenal amyloidosis was diagnosed using polarized light microscopy and Congo red stain. Monoclonal gammopathy was not detected in serum and urine tests, while the serum free light chain assay result was not specific. An increase in plasma cells in the bone marrow was not found. Secondary amyloidosis due to UC was suspected. The symptoms were resolved after glucocorticoid therapy.

Effects of experimental bleaching agents on the mineral content of sound and demineralized enamels

Abstract High concentrations of hydrogen peroxide can cause adverse effects on composition and structure of teeth. However, the addition of calcium and fluoride in bleaching agents may reduce enamel demineralization. Objective: To evaluate chemical changes of sound and demineralized enamels submitted to high concentrations of hydrogen peroxide containing fluoride (F) or calcium (Ca). Material and Methods: Enamel blocks of bovine incisors with standard dimensions were obtained and half of them were submitted to pH-cycling to promote initial enamel caries lesions. Sound and demineralized enamel samples were divided into (n=10): (C) Control (no whitening treatment); (HP) 35% hydrogen peroxide; and two experimental groups: (HPF) 35% HP+0.2% F and (HPC) 35% HP+0.2% Ca. Experimental groups were submitted to two in-office bleaching sessions and agents were applied 3 times for 15 min to each session. The control group was kept in remineralizing solution at 37°C during the bleaching treatment. The surface mineral content of sound and demineralized enamels was determined through Fourier Transform Raman spectroscopy (FT-Raman), Energy dispersive Micro X-ray fluorescence spectroscopy (μ-EDXRF); and the subsurface, through cross-sectional microhardness (CSMH). In addition, polarized light microscopy (PLM) images of enamel subsurface were observed. Results: According to three-way (FT-Raman and μ-EDXRF analyses) or two-way analysis of variance (ANOVA) (CSMH) and Tukey test (α=5%), the calcium or fluoride added to high-concentrated bleaching agents increased phosphate and carbonate concentrations on sound and demineralized enamels (p<0.05). However, HPC and HPF were unable to completely reverse the subsurface mineral loss promoted by bleaching on sound and demineralized enamels. The calcium/ phosphate (Ca/P) ratio of sound enamel decreased after HP treatment (p<0.001). Conclusion: Even though experimental bleaching agents with Ca or F reduced mineral loss for both sound and demineralized enamel surfaces, these agents were unable to reverse the enamel subsurface demineralization.

TiF4 varnish protects the retention of brackets to enamel after in vitro mild erosive challenge

Abstract The effect of fluoride agents on the retention of orthodontic brackets to enamel under erosive challenge is little investigated. Objective: The aim of this study was to evaluate the effect of titanium tetrafluoride (TiF4) and sodium fluoride (NaF) agents on the shear bond strength of brackets to enamel and on the enamel microhardness around brackets under erosive challenge. Methods: Brackets were bonded to bovine incisors. Five groups were formed according to fluoride application (n=10): TiF4 varnish, TiF4 solution, NaF varnish, NaF solution and control (without application). The specimens were submitted to erosive challenge (90 s cola drink/2h artificial saliva, 4x per day for 7 days). Solutions were applied before each erosive cycle and varnishes were applied once. Vickers Microhardness (VHN) was obtained before and after all cycles of erosion and the percentage of microhardness loss was calculated. Shear bond strength, adhesive remnant index and polarized light microscopy were conducted after erosion. The data were analyzed by ANOVA, Tukey, Kruskal-Wallis and Mann-Whitney U tests (α=0.05). Results: The %VHN had no statistically significant differences among the experimental groups. However, considering the comparisons of all groups with the control group, TiF4 varnish showed the highest protection from enamel demineralization (effect size of 2.94, while the effect size for the other groups was >2.4). The TiF4 varnish group had significantly higher shear bond strength compared to other groups. There was no difference among groups for adhesive remnant index. Polarized light microscopy showed higher demineralization depth for the control group. Conclusions: Application of NaF and TiF4 agents during mild erosive challenge minimized the enamel mineral loss around brackets, however only the experimental TiF4 varnish was able to prevent the reduction of shear bond strength of brackets to enamel.

Localized Gastric Amyloidosis with Kappa and Lambda Light Chain Co-Expression

Esophagogastroduodenoscopy for cancer screening was performed in a 55-year-old woman as part of a health screening program, and revealed a depressed lesion approximately 20 mm in diameter in the lesser curvature of the mid-gastric body. Several biopsy specimens were collected as the lesion resembled early gastric cancer; however, histopathologic evaluation revealed chronic active gastritis with an ulcer and amorphous eosinophilic material deposition. Congo red staining identified amyloid proteins, and apple-green birefringence was shown using polarized light microscopy. Immunohistochemical staining revealed the presence of kappa and lambda chain-positive plasma cells. There was no evidence of underlying plasma cell dyscrasia or amyloid deposition in other segments of the gastrointestinal tract. Echocardiography and computed tomography of the chest, abdomen, and pelvis did not show any significant findings. Thus, the patient was diagnosed with localized gastric amyloidosis with kappa and lambda light chain coexpression.

Role of Candida species from HIV infected children in enamel caries lesions: an in vitro study

Abstract Objectives This study analyzed the capacity of Candida spp. from dental biofilm of HIV infected (HIV+) children to demineralize primary molar enamel in vitro by Transversal Microhardness (TMH), Polarized Light Microscopy (PLM) and the quantity of calcium ions (Ca2+) released from the enamel. Material and Methods Candida spp. samples were isolated from the supragingival biofilm of HIV+ children. A hundred and forty (140) enamel blocks were randomly assigned to six groups: biofilm formed by C. albicans (Group 1); mixed biofilm formed by C. albicans and C. tropicalis (Group 2); mixed biofilm formed by C. albicans and C. parapsilosis (Group 3); mixed biofilm formed by C. albicans, C. parapsilosis and C. glabrata (Group 4); biofilm formed by C. albicans ATCC (Group 5) and medium without Candida (Group 6). Enamel blocks from each group were removed on days 3, 5, 8 and 15 after biofilm formation to evaluate the TMH and images of enamel were analyzed by PLM. The quantity of Ca2+ released, from Groups 1 and 6, was determined using an Atomic Absorption Spectrophotometer. The SPSS program was used for statistical analysis and the significance level was 5%. Results TMH showed a gradual reduction in enamel hardness (p<0.05) from the 1st to 15th day, but mainly five days after biofilm formation in all groups. The PLM showed superficial lesions indicating an increase in porosity. C. albicans caused the release of Ca2+ into suspension during biofilm formation. Conclusion Candida species from dental biofilm of HIV+ children can cause demineralization of primary enamel in vitro.

Organic cocoa extract -loaded surfactant-based systems intended to skin bioadhesion

ABSTRACT This study was to develop, characterize, and evaluate the physical-chemical stability, in vitro antioxidant activity and in vitro safety profile of liquid crystalline systems (LCS) and microemulsions (MEs) with and without organic cocoa (OC) extract. LCS stabilized by surfactant polyoxyethylene 20 cetyl ether, containing water and oleic acid were studied. LCS and MEs were characterized using polarized light microscopy, small angle X-ray scattering, rheology and in vitro bioadhesion, and were evaluated for a period of 30 days by visual aspects, centrifuge test, pH value and relative density. PLM and SAXS assays showed the presence of domains of MEs, cubic and hexagonal mesophasephases, varying the proportions of the components of the formulations; where in the addition of the extract did not change rheological behavior of the formulations. All of the formulations were stable in the period analyzed and presented higher bioadhesive strength. In vitro antioxidant activity suggests that LCS and MEs presented a high capacity to maintain the antioxidant activity of OC extract. The results showed that the incorporation of OC in LCS improved the safety profile, according to cytotoxicity assays of systems may be a promising platform to OC extract for topical application for the potential treatment of skin disorders.

Desenvolvimento e caracterização de filmes e comprimidos bucais a base de pectina e goma gelana para liberação tópica de triancinolona / Development and characterization of films and buccal tablets based on pectin and gellan gum for the topical release of triamcinolone

O tratamento farmacológico de patologias bucais é conduzido, geralmente, por via de administração local. No entanto, devido ao pouco tempo de permanência do fármaco no local de ação, esse tratamento pode ser bastante comprometido. Assim, este trabalho teve por objetivo o desenvolvimento de formas farmacêuticas que proporcionem a liberação local de triancinolona na cavidade oral. Foram produzidos filmes e comprimidos mucoadesivos a partir de polímeros naturais como gelana e pectina. Os filmes bucais foram preparados por meio de evaporação do solvente (solvent casting) utilizando diferentes quantidades de polímeros. As matérias-primas e os filmes foram caracterizados fisico quimicamente utilizando espectroscopia vibracional (in-infravermelho com transformada de Fourier e Raman) e difração de raios X. As propriedades físicas e mecânicas dos filmes também foram avaliadas. Além disso, realizou-se os ensaios de mucoadesividade e de dissolução do fármaco. Os comprimidos foram preparados por com-pressão direta usando como base os polímeros naturais. Diferentes parâmetros em relação as misturas e as formulações foram avaliados tais como as propriedades de fluxo dos pós constituintes, peso médio, dureza, friabilidade e desintegração. Em relação aos filmes bucais, estes foram obtidos com sucesso através de um método simples, sem a utilização de agentes reticulantes, ácidos ou solventes orgânicos. Todos apresentaram bons resultados nas propriedades avaliadas, no entanto as formulações com quantidades intermediarias de polímeros foram as melhores. Dentre as formulações de comprimidos preparadas, apenas 4 apresentaram boas características, no entanto, os resultados dos ensaios de dissolução mostraram que estas formulações têm capacidade de agir como sistema de liberação controlada de fármacos

Pharmacological treatment of oral pathologies is usually conducted by local administration. However, due to the short time the drug stays in the site of action, this treatment can be quite compromised. Thus, the objective of this work was to develop pharmaceutical forms that pro-vide the local release of triamcinolone in the oral cavity. Mucoadhesive films and tablets were made from natural polymers such as gellan and pectin. The buccal films were prepared by sol-vent casting using different amounts of polymers. The raw materials and films were characte-rized physically chemically using vibrational spectroscopy (FTIR and Raman) and X-ray diffraction. The physical and mechanical properties of the films were also evaluated. In addi-tion, the mucoadhesive and drug dissolution tests were performed. The tablets were prepared by direct pressing with the natural polymers. Different parameters in relation to mixtures and formulations were evaluated such as the flow properties of the constituent powders, average weight, hardness, friability and disintegration. In relation to oral films, these were successfully obtained by a simple method, without the use of crosslinking agents, acids or organic solvents. All presented good results in the evaluated properties, however the formulations with interme-diate amounts of polymers were the best. Among the tablet formulations prepared, only 4 sho-wed good characteristics, however, the dissolution test results showed that these formulations have the ability to act as a controlled drug delivery system

The role of Osterix protein in the pathogenesis of peripheral ossifying fibroma

Abstract Peripheral ossifying fibroma (POF) is a reactive lesion of oral tissues, associated with local factors such as trauma or presence of dental biofilm. POF treatment consists of curettage of the lesion combined with root scaling of adjacent teeth and/or removal of other sources of irritants. This study aimed to analyze the clinical and pathological features of POF and to investigate the immunoexpression of Osterix and STRO-1 proteins. Data such as age, gender, and size were obtained from 30 cases of POF. Microscopic features were assessed by conventional light microscopy using hematoxylin-eosin staining and immunohistochemical markers, and by polarized light microscopy using Picrosirius red staining. The age range was 11-70 years and 70% of the patients were female. Moreover, the size of POF varied from 0.2 to 5.0 cm; in 43.33% of the cases, the mineralized content consisted exclusively of bony trabeculae. The immunohistochemical analysis showed nuclear staining for Osterix in 63% and for STRO-1 in 20% of the cases. Mature collagen fibers were observed in mineralized tissue in 76.67% of the cases. The clinical and microscopic features observed were in agreement with those described in the literature. Osterix was overexpressed, while STRO-1 was poorly expressed. Osterix was expressed particularly in cells entrapped in and around mineralized tissue, indicating the presence of a stimulus that triggers the differentiation of these cells into osteoblasts or cementoblasts, i.e., cells that produce mineralized tissue. Based on our results, Osterix may play a role in the pathogenesis of POF.

Relationship between meiotic spindles visualization and intracytoplasmic sperm injection outcomes in human oocytes / 대한해부학회지

In assisted reproductive techniques, the operator attempts to select morphologically best embryos to predict embryo viability. Development of polarized light microscope, which evaluates the oocytes' spindles according to birefringence of living cells, had been helpful in oocyte selection. The aim of this study is evaluating the relationship between meiotic spindles visualization and intracytoplasmic sperm injection (ICSI) outcomes in human oocytes. In this study, 264 oocytes from 24 patients with an average age of 30.5±7.5 years with infertility duration of 1 to 10 years were collected. The oocytes were randomly allocated to the control injection group (n=126) and the oocyte imaging group (spindle-aligned group) (n=138). In the spindle-aligned group, the meiotic spindle was identified by means of polarized light microscope to align the spindle at 6 or 12 o'clock. Then the spindle-aligned group was divided into three sub-groups based on spindle morphology: fine, average, and (poor). After ICSI, embryos were checked every 24 hours and scored; 72 hours later, high-grade embryos were transferred intravaginally to uterus. This study showed that the fertilization rate in the spindle-aligned group was higher than the control group (P<0.05). After cleavage, a positive correlation was observed between spindle morphology and embryo morphology. Among the sub-groups of spindle-aligned group, the embryos' morphology of the fine group was better than the other subgroups and embryos of the poor group had lower quality and more fragmentation. The results revealed that the selection of oocytes based on meiotic spindle imaging can significantly improve the rate of fertilization and embryo cleavage and certainly increase the rate of implantation.

Development of the KOSHA Proficiency Testing Scheme on Asbestos Analysis in Korea

This commentary presents the regulatory backgrounds and development of the national proficiency testing (PT) scheme on asbestos analysis in the Republic of Korea. Since 2009, under the amended Occupational Safety and Health Act, the survey of asbestos in buildings and clearance test of asbestos removal works have been mandated to be carried out by the laboratories designated by the Ministry of Employment and Labor (MOEL) in the Republic of Korea. To assess the performance of asbestos laboratories, a PT scheme on asbestos analysis was launched by the Korea Occupational Safety and Health Agency (KOSHA) on behalf of the MOEL in 2007. Participating laboratories are evaluated once a year for fiber counting and bulk asbestos analysis by phase contrast microscopy and polarized light microscopy, respectively. Currently, the number of laboratory enrollments is > 200, and the percentage of passed laboratories is > 90. The current status and several significant changes in operation, sample preparations, and statistics of assigning the reference values of the KOSHA PT scheme on asbestos analysis are presented. Critical retrospect based on the experiences of operating the KOSHA PT scheme suggests considerations for developing a new national PT scheme for asbestos analysis.

Reference Values for Normal Epidermal Thickness in Koreans: A Histopathologic Investigation / 대한피부과학회지

BACKGROUND: Epidermal thickness is a useful quantitative histopathological parameter to predict different skin conditions. For accurate diagnosis, the reference values of normal skin histology are essential. Until now, little data regarding epidermal thickness in normal Korean skin have been available. OBJECTIVE: To investigate the thickness of the epidermis, stratum corneum, and cellular epidermis by skin biopsy and to compare their regional, age, and sex variations in Koreans. METHODS: A total of 119 normal human skin tissues from 117 subjects were included. Skin specimens were preserved in sections by formalin-paraffin techniques and measured by performing light microscopy and using a calibrated ruler. RESULTS: The mean thickness of the epidermis was 140.6±32.6 µm (mean±standard deviation). Significant regional variations of epidermal thickness were found (p0.5) or sex (p>0.05, except for the thickness of the stratum corneum of the legs [p=0.007]). CONCLUSION: Regional variations of epidermal thickness were demonstrated. These variations were mostly independent of age or sex, which conflicts somewhat with previous studies. We present this research as a preliminary study, which may provide reference values for skin histopathology and epidermal thickness in normal Korean skin.

Análise da imunoexpressão de OCT4 e CD44 em neoplasias de glândulas salivares menores e maiores / Immunohistochemical analysis of OCT4 and CD44 in minor salivary gland neoplasms and higher

As neoplasias de glândulas salivares exibem uma ampla variedade de comportamento biológico e grande diversidade morfológica, e esta heterogeneidade inerente a este grupo de tumores suscita o interesse em pesquisar estas lesões. As células-tronco são a principal fonte para a geração e manutenção da diversidade celular e homeostase do tecido, distúrbios na regulação destas células podem levar à produção de células-tronco alteradas, denominadas de células-tronco tumorais, que possuem potencial proliferativo e capazes de originar e/ou manter o tumor. Pesquisas acerca das células-tronco tumorais e das proteínas a elas associadas em algumas neoplasias orais têm sido desenvolvidas, no entanto, o papel destas em neoplasias de glândulas salivares não está ainda bem estabelecido. Desta forma, o objetivo deste estudo foi identificar células do parênquima tumoral que expressam marcadores de células-tronco tumorais, através da avaliação da imunoexpressão do OCT4 e CD44, em uma série de casos de neoplasias de glândulas salivares. A amostra foi constituída por 20 adenomas pleomórficos, 20 carcinomas mucoepidermóides e 20 carcinomas adenóides císticos localizados nas glândulas salivares menores e maiores. Todos os casos estudados exibiram expressão positiva para OCT4 e CD44, sendo observado que para ambos marcadores, as neoplasias localizadas nas glândulas salivares maiores exibiram maior imunomarcação quando comparada com as lesões das glândulas salivares menores apresentando diferença estatisticamente significativa (p=<0,001). Na amostra total e no grupo das glândulas salivares menores, as neoplasias malignas exibiram maior imunorreatividade para OCT4 do que o adenoma pleomórfico. No entanto, não foi encontrada diferenças estatisticamente significativas de imunoexpressões entre as lesões e entre suas classificações/gradações histomorfológicas. Analisando a correlação entre as imunoexpressões de OCT4 e CD44 foi observada uma correlação positiva moderada (r=0,444) com significância estatística entre os mesmos. A elevada expressão de OCT4 e CD44 pode indicar que estas proteínas desempenham papel importante na identificação de células-tronco tumorais, permitindo uma previsão do comportamento biológico das neoplasias de glândula salivar, apresentando níveis menores em tumores benignos e maiores nos tumores malignos.

Salivary gland neoplasms exhibit a wide variety of biological behavior and a high morphological diversity raises the interest in researching these lesions. The stem cells are the main source for the generation and maintenance of cell diversity, disorders in the regulation of these cells can lead to the production of altered stem cells, termed cancer stem cells capable of generate the tumor. Researches on cancer stem cells and associated proteins have been developed in some oral cancers; however, their role in salivary gland neoplasms is not well established. Thus, the aim of this study was to identify the tumor parenchyma cells exhibiting stem cell characteristics, by evaluating the immunoreactivity of OCT4 and CD44, in a number of cases of salivary gland neoplasms. The sample consisted of 20 pleomorphic adenomas, 20 mucoepidermoid carcinomas and 20 adenoid cystic carcinoma located in minor and major salivary glands. The expression of OCT4 and CD44 was evaluated by the percentage of positive cells (PP) and the intensity of expression (IE), it is realized the sum of the scores, resulting in the total score immunostaining (PIT) ranging 0-7. All studied cases showed positive expression of OCT4 and CD44 and higher values than the control groups. It was observed that for OCT4 luminal cells and non-luminal were immunostained in the case of pleomorphic adenomas and adenoid cystic carcinoma. Already the immunoreactivity of CD44 was particularly evident in the non-luminal cells of these lesions. In mucoepidermoid carcinomas for both markers, there was immunoreactivity in squamous and intermediate cells and absence of staining mucous cells. For both markers, a statistically significant higher immunostaining was verified in neoplasms located in the major salivary glands compared with lesions in the minor salivary (p<0.001). At the total sample and in the group of minor salivary glands, malignant neoplasms exhibited higher immunoreactivity for OCT4 than pleomorphic adenoma. However, there was no statistically significant difference between the lesions and between their classifications histomorphologic. Analyzing the correlation between OCT4 and CD44 immunoexpressions, a statistically significant moderate positive correlation (r = 0.444) was observed. The high expression of OCT4 and CD44 may indicate that these proteins play an important role in identifying cancer stem cells, allowing a prediction of biological behavior of salivary gland neoplasms.