Novel mutations in the SH3BP2 gene associated with sporadic central giant cell lesions and cherubism.

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.

Human papillomavirus infection in Rio de Janeiro, Brazil: a retrospective study

There is considerable data to support a central role for human papillomavirus (HPV) in the etiology of cervical cancer. More than a 100 HPV types have been described, and 40 have been isolated from benign and malignant genital lesions. Consequently, there is strong motivation to evaluate HPV testing for cervical cancer screening. Few studies concerning the natural history of HPV infection have been conducted in the state of Rio de Janeiro. We determined the prevalence of HPV types in female genital lesions by using Hybrid Capture Assay (HCA) and we retrospectively analyzed the course of HPV infection. Our sample included 788 women attended at Laboratórios Sérgio Franco. The average age of the participants was 29.6 years. HPV prevalence and cytological diagnosis were determined. The overall prevalence of HPV DNA in the study group was 50.1 percent (395/788), ranging from 25 percent (NORMAL) to 100 percent in high-grade intraepithelial lesions (HSIL). High risk HPV was found in 12 percent inflammatory, 58.3 percent HPV, 63.2 percent LSIL and 100 percent HSIL. A retrospective analysis of 78 patients showed that 22 presented persistent lesions, 2 had progressive lesions, 4 had regressive lesions, 13 showed latent infections, 18 were transiently infected and 19 were submitted to curative treatment. No cases of cancer were registered in this population, which can afford private medical care and regular follow-up exams. We suggest that HCA be used in specific cases involving persistent and recurrent lesions.

Human papillomavirus infection in Rio de Janeiro, Brazil: a retrospective study.

There is considerable data to support a central role for human papillomavirus (HPV) in the etiology of cervical cancer. More than a 100 HPV types have been described, and 40 have been isolated from benign and malignant genital lesions. Consequently, there is strong motivation to evaluate HPV testing for cervical cancer screening. Few studies concerning the natural history of HPV infection have been conducted in the state of Rio de Janeiro. We determined the prevalence of HPV types in female genital lesions by using Hybrid Capture Assay (HCA) and we retrospectively analyzed the course of HPV infection. Our sample included 788 women attended at Laboratórios Sérgio Franco. The average age of the participants was 29.6 years. HPV prevalence and cytological diagnosis were determined. The overall prevalence of HPV DNA in the study group was 50.1% (395/788), ranging from 25% (NORMAL) to 100% in high-grade intraepithelial lesions (HSIL). High risk HPV was found in 12% inflammatory, 58.3% HPV, 63.2% LSIL and 100% HSIL. A retrospective analysis of 78 patients showed that 22 presented persistent lesions, 2 had progressive lesions, 4 had regressive lesions, 13 showed latent infections, 18 were transiently infected and 19 were submitted to curative treatment. No cases of cancer were registered in this population, which can afford private medical care and regular follow-up exams. We suggest that HCA be used in specific cases involving persistent and recurrent lesions.

Ameloblastin gene (AMBN) mutations associated with epithelial odontogenic tumors.

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.

Investigation of the GSalpha gene in the diagnosis of fibrous dysplasia.

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.

Idiopathic bone cavity: a clinical, radiographic, and histological study.

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.

Oral myiasis by screwworm Cochliomyia hominivorax.

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.