Association of CD28 and CTLA-4 gene polymorphisms with aggressive periodontitis in Brazilians.

OBJECTIVE: Susceptibility to and severity of periodontal disease is influenced by gene polymorphisms related to the immune response. Co-stimulatory molecules, such as CD28 and CTLA-4, are critical in the development of such responses. Our hypothesis is that polymorphisms in genes that code for these molecules may be associated with periodontitis. The aim of the study was to investigate the association between +17 (T/C) CD28 and +49 (A/G) CTLA-4 gene polymorphisms and periodontitis in Brazilians. MATERIALS AND METHODS: Genomic DNA was obtained from oral swabs of 424 individuals categorized into three groups (control group, aggressive, and chronic periodontitis) considering clinical parameters such as probing depth and clinical attachment loss. The genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: There was an association between the T(-) genotype of the CD28 polymorphism and aggressive periodontitis (P = 0.04). Moreover, the A(+) genotype for CTLA-4 was associated with greater clinical attachment loss in non-smokers with aggressive periodontitis (P = 0.006, OR = 16.25, CI = 2.25-117.11). CONCLUSIONS: These findings show that T(-) in CD28 + 17 (T/C) and the A(+) in CTLA-4 +49 (A/G) genotypes are associated with susceptibility to aggressive periodontal disease. Thus, our study highlights these polymorphisms as potential genetic susceptibility markers of periodontitis in Brazilians.

Odontogenic tumours in children and adolescents: a collaborative study of 431 cases.

This study describes the oral and maxillofacial pathological characteristics of a series of odontogenic tumours in children and adolescents from three Brazilian reference centres. The records were reviewed for all odontogenic tumours in patients up to 18 years old based on criteria proposed by the World Health Organization (WHO) in 2005. Data concerning sex, age, skin colour and tumour location were collected and plotted. Four hundred and thirty one odontogenic tumours in children and adolescents were found, accounting for 37.5% of the total number of odontogenic tumours diagnosed. Benign tumours were predominant (99.8% of the cases), and odontoma was the most frequent type (41.4%), followed by keratocystic odontogenic tumours (25.5%) and ameloblastoma (14.6%). Odontogenic tumours were rarely detected in early childhood, and their prevalence increased with age. An almost equal distribution was observed with respect to sex and the site of the lesions. This study is the largest reported retrospective analysis describing odontogenic tumours in children and adolescents to date. The authors detected some variation in the relative frequency of odontogenic tumours compared with similar reports. Additional studies should be conducted based on the new WHO classification and predetermined age parameters to enable comparative analysis among different worldwide populations.

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.

An extreme case of cherubism.

We describe an 8-year-old boy who presented with severe facial swelling. This progressed rapidly and 17 months later he died of gastrointestinal and pulmonary infections. The diagnosis was initially brown tumour associated with hyperparathyroidism, but this was revised in the light of laboratory investigations that were within the reference ranges, and normal appearance of the parathyroids on exploration to that of an extreme case of cherubism that behaved in a locally aggressive manner.

Cysticercosis of the oral cavity: report of seven cases.

Cysticercosis is a condition in which a human acts as the intermediate host of the pork tapeworm Taenia solium. Although cysticercosis is a common disease in some regions of the world and can occur in any body site, oral lesions are rare. This paper reviews the natural history of the disease and reports on seven cases of oral cysticercosis.

Cell cycle-associated proteins in melanotic neuroectodermal tumor of infancy.

OBJECTIVE: The purpose of the present study was to compare the immunohistochemical expression of cell cycle-associated proteins in neuroblastic and melanocytic cell populations of melanotic neuroectodermal tumor of infancy. STUDY DESIGN: Three cases of melanotic neuroectodermal tumor of infancy were selected. The immunohistochemical expression of MDM-2, p53, proliferating cell nuclear antigen, cyclin D1, and cyclin A was assessed through use of the streptavidin-biotin-peroxidase complex technique. RESULTS: Positive immunostaining for MDM-2, proliferating cell nuclear antigen, cyclin D1, and cyclin A was occasionally observed in the large melanin-containing epithelioid cells. CONCLUSIONS: These data suggest that MDM-2 expression may be important for the development of melanotic neuroectodermal tumor of infancy and that the melanocytic cell population, not the neuroblastic one, is the proliferative component of the tumor.

Immunohistochemical expression of p53, MDM2, Ki-67 and PCNA in central giant cell granuloma and giant cell tumor.

Central giant cell granuloma (CGCG) is a reactive bone lesion that occurs mainly in the jaws. The giant cell tumour (GCT) is a benign locally aggressive neoplasm located near the articular end of tubular bones. Both lesions are characterised histologically by multinucleated giant cells in a background of ovoid to spindle-shaped mesenchymal cells. There is a basic question whether both lesions are separate entities or variants of the same disease. The study of cell cycle-associated proteins may give insights into clarifying such question. The expression of these proteins is also important to determine the cell cycle regulation in both tumours. The purpose of this study was to evaluate the immunohistochemical expression of p53, MDM2, Ki-67 and PCNA in CGCG and GCT. The results demonstrated that, despite the lack of p53 immunoreactivity, all the samples showed wide expression of MDM2. The percentage of Ki-67- and PCNA-positive cells in CGCG was statistically higher than that of GCT Our findings show that CGCG has a higher proliferative activity compared with that of the GCT. Our results also suggest that p53 inactivation by MDM2 expression may be involved in the pathogenesis of giant cell lesions of the jaws and long bones.

Immunocytochemistry of fine-needle aspirates from central giant cell granuloma.

Fine needle aspiration biopsy (FNAB) is an important technique in the diagnosis of oral and maxillofacial conditions. We describe here the cytological and immunocytological findings in four patients with central giant cell granuloma. All the aspirates showed mononuclear cells associated with many giant cells. We conclude that immunocytochemical examination of FNAB specimens helps to confirm the provisional clinical diagnosis of central giant cell granuloma.

CD30+ lymphocytes in chronic gingivitis from HIV-positive patients: a pilot study.

Th2 type lymphocytes are characterized by high expression of CD30 glycoprotein. Increased serum levels of CD30 and Th2 IL-4 producing T-cells are found during AIDS progression. Since HIV-positive patients are more susceptible to periodontal disease, quantitative analysis of positive cells for the CD30 receptor in chronic gingivitis of both HIV-infected and non-infected patients (NSG) would help to clarify the immunoregulation of HIV-associated periodontal diseases. The purpose of this study was to evaluate CD30+ lymphocytes in gingival biopsies from sites exhibiting chronic gingivitis on HIV-positive patients (CG-HIV) and NSG. A biotin-streptavidin amplified system was used for identification of the CD30 receptor. The results demonstrated increased proportions of Th2 cells in CG-HIV as compared to NSG. Additional studies are necessary to understand the importance of these cells to the biological activity or inactivity of the disease.

[New foci of transmission of Schistosoma mansoni in the state of Pará]. / Novos focos de transmissão do Schistosoma mansoni no Estado do Pará.

Two new foci of transmission of Schistosoma mansoni in the state of Pará are recorded, with the finding of naturally infected Biomphalaria glabrata in the municipalities of Viseu and Belém. Uninfected specimens of Biomphalaria straminea, as well as the planorbid species Biomphalaria schrammi, Drepanotrema lucidum and D. anatinum, were found in the same area.