RESUMEN
Central giant cell lesion (CGCL) is a reactive bone lesion that occurs mainly in the mandible, characterized by the multinucleated osteoclast-like giant cells in a background of oval to spindle-shaped mononuclear cells. The etiology is unknown and occurs more commonly in young adults. Cherubism, a rare disease found predominantly in females has histologic characteristics indistinguishable from those of CGCL and is caused by mutations mostly present in exon 9 of the SH3BP2 gene. In this study, we investigated four cases of CGCL and one case of cherubism. DNA was extracted from peripheral blood and tumor tissue and all coding and flanking regions of the SH3BP2 amplified by PCR and directly sequenced to identify underlying mutations. Two novel mutations were found; a heterozygous missense mutation c.1442A>T (Q481L) in exon 11 in one sporadic case of CGCL and a heterozygous germline and tumor tissue missense mutation c.320C>T (T107M) in exon 4 in one patient with cherubism. These findings open a new window to investigate the possible relationship between the pathogenesis of the cherubism and CGCL.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Querubismo/genética , Granuloma de Células Gigantes/genética , Enfermedades Maxilomandibulares/genética , Mutación/genética , Dominios Homologos src/genética , Adenina , Adulto , Niño , Citosina , Exones/genética , Femenino , Mutación de Línea Germinal/genética , Glutamina/genética , Heterocigoto , Humanos , Leucina/genética , Masculino , Metionina/genética , Persona de Mediana Edad , Mutación Missense/genética , Treonina/genética , Timina , Adulto JovenRESUMEN
Ameloblastin (AMBN, MIM *601259) gene expresses an important protein (AMBN), present in the organic matrix of enamel. The AMBN protein has an important role in the differentiation of ameloblast cells and epithelium-mesenchyme signaling during odontogenesis which prompted us to investigate this gene in aggressive epithelial odontogenic tumors, such as ameloblastomas, and in some non-aggressive ones, such as the adenomatoid odontogenic tumor and the squamous odontogenic tumor. Six cases of epithelial odontogenic tumors were studied and normal cells of the patient's mucosa were used as negative controls. The results demonstrated novel mutations in all tumors, while mucosal cells showed the wild type DNA sequence. Our data demonstrates that AMBN gene has an important role in the tumorigenesis of subtypes of epithelial odontogenic tumors and that this phenotypic heterogeneity could be caused by genetic heterogeneity.
Asunto(s)
Proteínas del Esmalte Dental/genética , Neoplasias de la Boca/genética , Tumores Odontogénicos/genética , Ameloblastoma/genética , Ameloblastoma/patología , Secuencia de Bases , Células Epiteliales/patología , Exones/genética , Humanos , Datos de Secuencia Molecular , Mucosa Bucal/patología , Neoplasias de la Boca/patología , Mutación , Tumores Odontogénicos/patologíaRESUMEN
Fibrous dysplasia is a benign fibro-osseous disease of bone and its etiology has been previously established. Activating mutations in the gene that encodes the alpha subunit of stimulatory G protein (G(S)alpha) has been described in monostotic and polyostotic fibrous dysplasia and in the McCune-Albright syndrome. The present report describes a patient with monostotic fibrous dysplasia which diagnosis was confirmed by sequencing of the G(S)alpha gene, demonstrating a heterozygous missense mutation on codon 201 (201C --> T). Due to the high prevalence of G(S)alpha gene mutations in fibrous dysplasia in contrast to other benign and malignant fibrous-osseous lesions, mutational analysis are an additional and helpful parameter for the diagnosis of fibrous dysplasia in selected cases.
Asunto(s)
Displasia Fibrosa Monostótica/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Enfermedades Maxilares/genética , Adolescente , Codón/genética , Citosina , Femenino , Heterocigoto , Humanos , Mutación Missense/genética , TiminaRESUMEN
The aim of the present study was to evaluate the clinical, radiographic and histological characteristics of idiopathic bone cavities from the Oral Pathology archives at Universidade Federal de Minas Gerais. Forty-three cases were retrieved. Age, sex, some radiographic variables and morphological variables measured of the connective tissue, were studied. The results showed the men who developed cavities tended to be younger than women (median 16 years (range 11-48) compared with 18 (12-64)). Radiographically rounded lesions that were single, unilocular, and small were more common in younger patients. While rounded cavities occurred mainly in the anterior region, cavities with interdental scalloping occurred in the posterior area. The median age of the patients with thin connective tissue on the wall of the bony cavity was lower than that of those with a thicker lining. In conclusion, the present study shows that there is a significant relation between age and sex, radiographic and histological variables. These findings may contribute to the diagnosis of idiopathic bone cavities.
Asunto(s)
Quistes Maxilomandibulares/clasificación , Adolescente , Adulto , Factores de Edad , Brasil , Niño , Tejido Conectivo/diagnóstico por imagen , Tejido Conectivo/patología , Femenino , Humanos , Quistes Maxilomandibulares/diagnóstico por imagen , Quistes Maxilomandibulares/patología , Masculino , Enfermedades Mandibulares/clasificación , Enfermedades Mandibulares/diagnóstico por imagen , Enfermedades Mandibulares/patología , Persona de Mediana Edad , Radiografía , Factores Sexuales , Estadísticas no ParamétricasRESUMEN
We report a rare case of periodontal myiasis by New World screwworm Cochliomyia hominivorax, an obligatory larval parasite, in a 66-year-old woman. The myiasis occurred in the anterior upper jaw associated with a pre-existent generalised periodontitis. About 40 larvae were removed from the lesion. One week later the periodontal tissues were healing normally and the patient was referred to a periodontist. As all of the larvae were in the last stage, they were probably deposited 5-7 days before.
