Radiographic imaging pattern of ossifying fibroma mimicking ameloblastoma: a case report

Radiographic examinations complement the anamnesis and physical exam with the purpose of reaching diagnosis, prognosis and treatment planning. In this case report, a 48 year-old male Caucasian patient was referred to an oral and maxillofacial surgeon by a general practitioner after a panoramic radiography for treatment planning; the implant surgery follow-up portrayed a multilocular radiolucent image at the left posterior mandible. Based solely on the panoramic radiography, the diagnostic hypothesis was ameloblastoma. The surgeon decided to perform an incisional biopsy. However, during the procedure, the professional noted that the lesion was easily detached from the adjacent bone and opted for the total removal of the lesion, thus altering its diagnostic hypothesis to central ossifying fibroma (COF). The histopathological result confirmed the diagnostic hypothesis provided by the surgeon, i.e. COF. Although multilocular presentation is not common, COF should be considered in the scope of multilocular radiolucent lesions of the jaws. In addition, computerized tomography imaging exam complemented by surgical and histopathological aspects should be considered for establishing the final diagnosis and conducting the therapeutic approach.Os exames radiográficos complementam a anamnese e o exame físico a fim de estabelecer o diagnóstico, o prognóstico e o planejamento do tratamento. Neste relato de caso, um paciente do sexo masculino, de 48 anos, foi encaminhado a um cirurgião bucomaxilofacial por um clínico geral após uma radiografia panorâmica para o planejamento do tratamento; o seguimento da cirurgia de implante retratou uma imagem radiotransparente multilocular na mandíbula posterior esquerda. Baseado apenas na radiografia panorâmica, a hipótese diagnóstica foi ameloblastoma. O cirurgião decidiu realizar uma biópsia incisional. No entanto, durante o procedimento, o profissional notou que a lesão era facilmente separada do osso adjacente e optou pela retirada total da lesão, alterando sua hipótese diagnóstica para fibroma ossificante central (FCO). O resultado histopatológico confirmou a hipótese diagnóstica do cirurgião, ou seja, o COF. Embora a apresentação multilocular não seja comum, o FCO deve ser considerado em casos de lesões radiotransparentes multiloculares das mandíbulas. Além disso, o exame de tomografia computadorizada complementado por aspectos cirúrgicos e histopatológicos deve ser considerado para estabelecer o diagnóstico final e conduzir a abordagem terapêutica

Localização de transcritos de Bmp-4, Shh e Wnt-5a durante as fases iniciais do desenvolvimento dentário de camundongos por hibridização in situ

A comparative nonisotopic in situ hybridization (ISH) analysis was carried out for the detection of Bmp-4, Shh and Wnt-5a transcripts during mice odontogenesis from initiation to cap stage. Bmp-4 was expressed early in the epithelium and then in the underlying mesenchyme. Shh expression was seen in the odontogenic epithelial lining thickening, being stronger in the enamel knot area, during the cap stage. Wnt-5a transcripts were expressed only in the mesenchyme during the initiation, bud and cap stages, with strong expression in the dental mesenchyme during the bud stage. The present results showed that Bmp-4, Shh and Wnt-5a are expressed since the very early stages of tooth development, and they suggest that the Wnt-5a gene is expressed in different cell populations than Bmp-4 and Shh.No presente trabalho, realizou-se uma análise comparativa não isotópica por hibridização in situ a fim de se detectar a presença de transcritos de Bmp-4, Shh e Wnt-5a durante as fases iniciais da odontogênese em camundongos, desde a iniciação até o estágio de capuz. No estágio de iniciação, observou-se expressão precoce de Bmp-4 no epitélio e no mesênquima subjacente, enquanto que a expressão de Shh ocorreu durante o estágio de capuz, na região de espessamento do revestimento epitelial odontogênico, tornando-se mais intensa na área de nó do esmalte. Os transcritos de Wnt-5a foram expressos somente no mesênquima durante os estágios de iniciação, botão e capuz, com intenso sinal na região no mesênquima na fase de botão. Estes resultados mostraram que Bmp-4, Shh e Wnt-5a são expressos desde os estágios mais precoces do desenvolvimento dentário, sugerindo que o gene Wnt-5a seja expresso em populações celulares distintas daquelas que expressam Bmp-4 e Shh.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)University of São Paulo School of Dentistry Department of Oral PathologyUniversity of São Paulo Biomedical Sciences Institute Department of ImmunologyFederal University of São Paulo Center for Development of Animal ModelsUNIFESP, Center for Development of Animal ModelsSciEL

Avaliação de três métodos de extração de DNA de material parafinado para amplificação de DNA genômico pela técnica da PCR

There are several protocols reported in the literature for the extraction of genomic DNA from formalin-fixed paraffin-embedded samples. Genomic DNA is utilized in molecular analyses, including PCR. This study compares three different methods for the extraction of genomic DNA from formalin-fixed paraffin-embedded (inflammatory fibrous hyperplasia) and non-formalin-fixed (normal oral mucosa) samples: phenol with enzymatic digestion, and silica with and without enzymatic digestion. The amplification of DNA by means of the PCR technique was carried out with primers for the exon 7 of human keratin type 14. Amplicons were analyzed by means of electrophoresis in an 8% polyacrylamide gel with 5% glycerol, followed by silver-staining visualization. The phenol/enzymatic digestion and the silica/enzymatic digestion methods provided amplicons from both tissue samples. The method described is a potential aid in the establishment of the histopathologic diagnosis and in retrospective studies with archival paraffin-embedded samples.Existem na literatura vários protocolos para extração de DNA genômico a partir de material fixado em formol e embebido em parafina. A obtenção de DNA genômico é importante para realização de experimentos em biologia molecular, dentre eles a PCR. Este trabalho teve por objetivo otimizar a extração de DNA genômico a partir de material fixado (hiperplasia fibrosa inflamatória) e não-fixado (mucosa bucal normal) em formol, comparando-se três metodologias diferentes: fenol com digestão enzimática, partículas de sílica com e sem digestão enzimática. Para amplificação do DNA pela técnica da PCR, utilizou-se iniciadores para o éxon 7 da citoqueratina humana tipo 14. O sucesso da amplificação foi verificado pela eletroforese do produto em gel de poliacrilamida 8% contendo glicerol 5% corado com prata. Obteve-se amplificação do DNA genômico extraído com fenol/digestão enzimática e com partículas de sílica/digestão enzimática, para ambos tecidos utilizados. O método padronizado tem potencial para auxiliar no diagnóstico histopatológico, assim como no estudo retrospectivo de material de arquivo

Immunohistochemical analysis for CD21, CD35, Caldesmon and S100 protein on dendritic cells types in oral lymphomas

OBJECTIVE: Follicular dendritic cells (FDCs) and interdigitating dendritic cells (IDCs) are dendritic cells found in lymphoid follicles, reactive follicles and in lymphomas. The goal of this study was to evaluate the presence and distribution of FDCs and IDCs in oral lymphomas. MATERIAL AND METHODS: Immunohistochemistry reactions were applied to 50 oral lymphomas using the antibodies anti-CD21, anti-CD35 and anti-caldesmon to FDCs, and anti-S100 protein to IDCs. Caldesmon+/FDCs and S100+/IDCs were quantified in Imagelab® software. RESULTS: FDCs revealed by CD21 and CD35 were positively stained in two cases of diffuse large B-cell lymphoma, one MALT lymphoma, and in one case of mantle cell lymphoma. FDCs were immunopositive to caldesmon in all cases, as well as IDCs to S100 protein. Burkitt lymphoma presented a lower amount of caldesmon+/FDCs and S100+/IDCs than diffuse large B-cell lymphoma and plasmablastic lymphoma of the oral mucosa type. CONCLUSIONS: The microenvironment determined by neoplastic lymphoid cells in oral lymphomas is responsible by the development and expression of dendritic cells types

Evidence of a noncoding transcript of the RIPK2 gene overexpressed in head and neck tumor

Receptor-interacting proteins are a family of serine/threonine kinases, which integrate extra and intracellular stress signals caused by different factors, including infections, inflammation and DNA damage. Receptor-interacting serine/threonine-protein kinase 2 (RIP-2) is a member of this family and an important component of the nuclear factor NF-kappa-B signaling pathway. The corresponding human gene RIPK2 generates two transcripts by alternative splicing, the full-length and a short transcript. The short transcript has a truncated 5’ sequence, which results in a predicted isoform with a partial kinase domain but able to transduce signals through its caspase recruitment domain. In this study, the expression of RIPK2 was investigated in human tissue samples and, in order to determine if both transcripts are similarly regulated at the transcriptional level, cancer cell lines were submitted to temperature and acid stresses. We observed that both transcripts are expressed in all tissues analyzed, with higher expression of the short one in tumor samples, and they are differentially regulated following temperature stress. Despite transcription, no corresponding protein for the short transcript was detected in tissues and cell lines analyzed. We propose that the shorter transcript is a noncoding RNA and that its presence in the cell may play regulatory roles and affect inflammation and other biological processes related to the kinase activity of RIP-2.Instituto de Biotecnologia y Biologia Molecula