Search results for "Ontología"
showing 10 items of 1426 documents
Synchronous metastatic cutaneous squamous cell carcinoma and chronic lymphocytic leukaemia/small lymphocytic lymphoma in a cervical lymph node: case …
2015
The synchronous occurrence of two different neoplasias is an uncommon event, which may arise between tumors originating in the same organ or in cancer-to-cancer metastasis. We report a rare case of chronic lymphocytic leukaemia / small lymphocytic lymphoma associated with a cutaneous metastatic squamous cell carcinoma in a cervical lymph node. In the affected lymph node, it was observed an effacement of the normal architecture by neoplastic lymphocytes and it was noted the presence of neoplastic invasive epithelial islands. Immunohistochemical analysis demonstrated that lymphocytic proliferation was positive for CD20, CD5, CD23 and Kappa, and negative for CD3, CD10, Cyclin D1 and Lambda. Th…
Expresión de las moléculas del Complejo Mayor de Histocompatibilidad clase II y moléculas co-estimuladoras en carcinomas orales in vitro
2005
El descubrimiento de que el epitelio escamoso estratificado que cubre la mucosa oral podia expresar moleculas del Complejo Mayor de Histocompatibilidad clase II en varias condiciones patologicas de tipo inflamatorio abrio la posibilidad de que los queratinocitos orales sean celulas inmunologicamente activas, las cuales pueden funcionar con .celulas presentadoras de antigenos'ñ. Para una efectiva activacion de los linfocitos T, las celulas presentadoras de antigenos requieren, ademas de la expresion de moleculas del Complejo Mayor de Histocompatibilidad clase II, senales co-estimuladoras. El proposito del presente estudio fue determinar la expresion de moleculas del Complejo Mayor de Histoco…
Successful closure of the root apex in non-vital permanent incisors with wide open apices using single calcium hydroxide (caoh) dressing: report of 2…
2010
Endodontic management of immature non vital permanent teeth in young pediatric patients is a great challenge to dentists. The walls of the root canals are frequently divergent and open apexes make debridement and obturation difficult. Thus closure of root apex is very essential for success of the endodontic treatment. Although different materials are used for the apexification procedure, calcium hydroxide is the material of choice for apical barrier formation and healing. There are different opinions regarding frequency of CaOH dressing change to induce complete closure of the apex. Literature suggests that dressing should be changed frequently. Therefore the aim of the present article is t…
Aislamiento de Candida dubliniensis en un adolescente con estomatitis protésica
2005
Objetivos: Utilizar varios métodos que permiten la diferenciación entre Candida albicans y Candida dubliniensis en un intento de conocer si C. dubliniensis puede ser aislada de la cavidad oral de adolescentes con prótesis ortopédicas orales. Materiales y métodos: Se aislaron 12 cepas de género Candida procedentes de mucosa palatina y de soporte de prótesis de 12 pacientes adolescentes portadores de prótesis ortopédicas orales. Para la diferenciación entre C. albicans y C. dubliniensis se utilizaron varias pruebas fenotípicas (la asimilación de fuentes de carbono con el método comercial ID 32C, el crecimiento en agar glucosado de Sabouraud a 45 ºC, la producción abundante de clamidosporas en…
Metástasis mandibular por carcinoma hepático: un infrecuente caso con severa hemorragia
2004
El carcinoma hepatocelular (CH) es relativamente infrecuente en Europa y Estados Unidos, a pesar de que en este último país se diagnostican más de 13.000 nuevos casos cada año. Las metástasis mandibulares por CH son inusuales, recogiéndose en la literatura hasta el momento, 50 casos. En el presente trabajo se documenta un nuevo caso, correspondiente a un varón de 54 años que presentó una metástasis por HC en el cuerpo mandibular derecho, al año del tratamiento de su tumor primario. El curetaje-biopsia de la lesión se acompañó de una profusa hemorragia. El paciente falleció a los seis meses de la biopsia, con múltiples metástasis. Se describen las posibles vías de diseminación hematógena de …
Metástasis en hueso maxilar superior de adenocarcinoma de esófago: presentación de un caso clínico
2005
Las metástasis en cavidad oral son lesiones raras que representan aproximadamente el 1% de todas las neoplasias malignas de cavidad oral. Las metástasis orales se localizan en un 80-90% en mandíbula, siendo mas raras en maxilar superior. Las metástasis en tejidos blandos de boca son raras, y es encía donde con mayor frecuencia se localizan las metástasis en tejidos blandos en boca. Los tumores primarios que metastatizan a boca son los más frecuentes pulmón, mama y riñón. Las metástasis en cavidad oral es como consecuencia de una diseminación a distancia de la enfermedad e indica un mal pronóstico, con una supervivencia corta. Aquí presentamos un caso clínico de un paciente diagnosticado de …
All-trans retinoic acid restores gap junctional intercellular communication between oral cancer cells with upregulation of Cx32 and Cx43 expressions …
2012
Objective: All-trans retinoic acid (ATRA) has been demonstrated to inhibit tumor growth by restoration of gap junctional intercellular communication (GJIC) via upregulation of connexin (Cx) expression in some solid tumors. However, the relationship between ATRA and GJIC remains unclear in oral squamous cell carcinoma (OSCC). The aim of this study was to investigate the effect of ATRA on the GJIC function of OSCC. Study design: We measured the effects of ATRA on the viability and cell cycle distribution of SCC9 and Tca8113 OSCC cells. The GJIC function was observed using the scrape-loading dye transfer technique, and the mRNA and protein levels of Cx32 and Cx43 were detected by qRT-PCR, West…
Presence of matrix vesicles in the body of odontoblasts and in the inner third of dentinal tissue: a scanning electron microscopic study.
2012
Objectives: The aim of this report is to present the results of a scanning electron microscopic study on the presence of matrix vesicles (MVs) found in human dentine. Study Design: Dentin tissue from 20 human bicuspids was analyzed by means of scanning electron microscopy. Results: MVs were found as outgrowths of the cellular membrane of the odontoblastic body, the more proximal portion of the odontoblastic process before entering the dentinal tubule and in the odontoblastic process within the inner third of the dentin. Size of MVs varied depending on location. In the inner third of dentin, they were seen in diverse positions; as membranal outgrowths, deriving from the odontoblastic process…
Cleaning and retreatment protocol for a debonded ceramic restoration
2014
Objectives: The aim of this article is to propose a resin cement cleaning protocol for use before recementing a debonded restoration. Study Design: Ceramic samples were fabricated from IPS d.sign® and IPS e.max Press® and were treated with hydrofluoric acid etching (HF), or HF+silane (S), or HF+S+adhesive or HF+S+A+resin cement. All samples were placed in a furnace at 650º for one minute in order to attempt to pyrolyze the composite. Each step was examined under scanning electron microscopy (SEM). Results: When the cleaning protocol had been performed, it left a clean and retentive surface. Conclusions: If the restoration is placed in a furnace at 650º for one minute, the composite cement w…
Etiological factors in second mandibular molar impaction.
2013
Objectives: The impaction of the second mandibular molar (MM2) has recently become more prevalent. Several etiological hypothesis have been proposed to investigate the association between skeletal features and impaction of MM2. The aims of this study were to analyze the skeletal features in patients with MM2 impaction and the association between arrested eruption of MM2 and the presence of the third mandibular molar (MM3). Study Design: In this retrospective study 48 subjects from 3,530 Caucasian orthodontic patients with MM2 impaction were included in a study group (SG) and compared to a control group (CG) of 200 subjects without MM2 impaction. Panoramic radiographs evaluated the presence …