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Featured researches published by Op de Almeida.


International Journal of Oral and Maxillofacial Surgery | 2011

Clinicopathological factors are predictors of distant metastasis from major salivary gland carcinomas

Fernanda Viviane Mariano; S.D. da Silva; T.C. Chulan; Op de Almeida; L.P. Kowalski

The risk of distant metastasis of salivary gland cancers has usually been associated with histological type, tumour size, and site. The aim of this study was to evaluate a series of patients with major salivary gland carcinomas in order to identify potential risk factors associated with distant metastasis. 255 patients treated for major salivary gland carcinoma in Brazil from 1953 to 2004 were reviewed. Clinical and treatment data were obtained from the medical records and histological features reviewed. 57 (22%) of 255 patients had distant metastasis. The lungs were the most common metastatic site (40 cases, 65%) and adenoid cystic carcinoma the most frequent histological type involved (27 cases, 47%). The percentage of tumours in the submandibular, parotid, and sublingual glands that presented distant metastasis was 42%, 20%, and 17%, respectively. These results provide evidences that clinicopathological factors (tumour site and histology) are significant predictors of distant metastasis in patients with major salivary gland carcinomas.


Oral Diseases | 2012

Cleidocranial dysplasia: oral features and genetic analysis of 11 patients

A Bufalino; Lmr Paranaíba; Adriele Ferreira Gouvêa; Luiz Alcino Monteiro Gueiros; Hercílio Martelli-Júnior; Jacks Jorge Junior; M. A. Lopes; Edgard Graner; Op de Almeida; Pablo Agustin Vargas; Ricardo D. Coletta

BACKGROUND Cleidocranial dysplasia (CCD) is a dominantly inherited autosomal disease characterized by typical bone defects including short stature, persistently open or delayed closure of the cranial sutures, and hypoplastic or aplastic clavicles. Oral features are frequent and include supernumerary teeth, delayed eruption or impaction of the permanent teeth, and malocclusion. Heterozygous mutations in RUNX2 gene, which encodes a transcription factor essential for osteoblast differentiation, were identified as the etiological cause of CCD. OBJECTIVE AND METHODS Herein, we performed physical and radiographic examination and screening for RUNX2 mutations in 11 patients from five families with CCD. RESULTS All patients demonstrated the classical phenotypes related to CCD. Families whose affected members had several dental alterations such as multiple impacted and supernumerary teeth demonstrated heterozygous missense mutations (R190Q and R225Q) that impair the runt domain of RUNX2. On the other hand, CCD patients from families with low frequency of dental abnormalities showed no mutation in RUNX2 or mutation outside of the runt domain (Q292fs→X299). CONCLUSION The current findings suggest a correlation between dental alterations and mutations in the runt domain of RUNX2 in CCD patients. Further clinical and genetic studies are needed to clarify the relationship between phenotypes and genotypes in CCD and to identify other factors that might influence the clinical features of this uncommon disease.


Journal of Oral Pathology & Medicine | 2009

Clinical, histological and immunohistochemical findings in oral Kaposi's sarcoma in a series of Mexican AIDS patients. Comparative study.

Velia Ramírez-Amador; Guillermo Martínez-Mata; I. González-Ramírez; Gabriela Anaya-Saavedra; Op de Almeida

BACKGROUND The origin of spindle cells (SC) in oral Kaposis sarcoma (OKS) is still an intriguing aspect. Thus the aim of the present study was to compare the clinical, histological and immunohistochemical characteristics of OKS and oral pyogenic granuloma (OPG), in order to contribute to the knowledge of the cells involved in Kaposis sarcoma pathogenesis. METHODS In this retrospective, observational and comparative study, 39 OKS and 30 OPG cases were included. Immunohistochemical studies were performed for vimentin, alpha SMA, desmin, C-kit, CD34, D2-40 and LANA-1 [human herpesvirus-8(HHV-8)]. Statistical comparisons were done using the chi-square and Wilcoxon-Mann-Whitney rank sum tests. RESULTS Fourteen (35.9%) OKS cases also affected the skin, and 83.8% involved the palate. All OKS and OPG were positive for vimentin and CD34. OKS samples were positive for alpha SMA, and 25.6% expressed C-kit. All OKS cases were positive for HHV-8, and the number of positive cells increased significantly from early / intermediate to late histological stage. D2-40 was expressed in the cellular component and vascular walls of all OKS cases, but it was negative in OPG. HHV-8 expression was increased in late histological stages of OKS lesions. CONCLUSIONS The expression of D2-40 marker in the vascular walls and SC supports the view of a lymphatic differentiation in neoplastic cells of OKS. Desmin, alpha SMA, D2-40, C-kit and HHV-8 were the main markers differently expressed in OKS and OPG.


Cytopathology | 2007

Fine needle aspiration cytology as an additional tool in the diagnosis of odontogenic keratocyst

Pablo Agustin Vargas; D.E.C. Perez; G. M. Mata; Op de Almeida; A. V. Jones; Renê Gerhard

Objective:  The aim of this study was to assess the use of fine needle aspiration cytology (FNAC) in diagnosis of odontogenic keratocyst (OKC), as well as to describe the cytological and immunohistochemical features.


Archives of Oral Biology | 2001

The effect of cyclosporin A on the activity of matrix metalloproteinases during the healing of rat molar extraction wounds.

H.C.C.R Silva; Ricardo D. Coletta; Jacks Jorge; Glaucia Bolzani; Op de Almeida; Edgard Graner

Cyclosporin A (CyA) is a cyclic peptide used as an immunosuppressive agent because it can block the synthesis of interleukin-2 and other cytokines produced by CD4+ lymphocytes. It is widely used for the prevention of allograft rejection and treatment of autoimmune diseases. Several side-effects of CyA treatment have been reported, among which are chronic nephrotoxicity, hepatotoxicity and neurotoxicity, lymphoproliferative neoplasms, hypertension, thromboembolic complications and gingival overgrowth. Here, using a rat molar model, it is demonstrated that CyA immunosuppression inhibits the activity of matrix metalloproteinases 2 and 9 in the early phase of granulation tissue in the healing dental socket. These observations suggest that CyA may interfere with the wound healing following dental extractions.


International Journal of Oral and Maxillofacial Surgery | 2013

Carcinoma ex pleomorphic adenoma in a Brazilian population: clinico-pathological analysis of 38 cases

Fernanda Viviane Mariano; A.L.F. Noronha; Rogério Oliveira Gondak; A.M. de A.M. Altemani; Op de Almeida; L.P. Kowalski

Carcinoma ex pleomorphic adenoma (CXPA) is a rare tumour, with different prevalence rates reported among studies. Epidemiological studies of large series of CXPAs in developing countries are scarce. The aim of the present study was to describe Brazilian patients with CXPA; this was a retrospective study of 38 patients. Demographic and clinico-pathological features were evaluated. No preferential gender was found, and the mean age at diagnosis was 57.6 years. The most commonly involved site was the parotid, followed by the submandibular and the minor salivary glands. A prevalence of clinical stages III and IV was observed at diagnosis. The most common histological subtypes were salivary duct carcinoma, adenocarcinoma not otherwise specified, myoepithelial carcinoma, and epithelial-myoepithelial carcinoma. Moreover, by invasive phase, most were frankly invasive carcinoma. Recurrence was observed in seven out of 24 patients with outcome information available, and all were invasive cases. All seven patients died of causes related to the disease. The distributions of cases according to age, gender, tumour location, and clinical stage were similar to those reported in the literature. Frankly invasive cases presented a worse prognosis. More information is needed to further our understanding of the clinico-pathological aspects of CXPA.


Oral Diseases | 2011

Expression of fatty acid synthase (FASN) in oral nevi and melanoma

Bab de Andrade; Jorge Esquiche León; Roman Carlos; Wilson Delgado-Azañero; Adalberto Mosqueda-Taylor; Edgard Graner; Op de Almeida

OBJECTIVE The aim of this study was to determine the expression of fatty acid synthase (FASN) in oral nevi and melanomas, comparing the results with correspondent cutaneous lesions. MATERIALS AND METHODS Expression of FASN was evaluated by immunohistochemistry in 51 oral melanocytic lesions, including 38 intramucosal nevi and 13 primary oral melanomas, in 10 cutaneous nevi and in 14 melanomas. RESULTS Fatty acid synthase was strongly expressed only in melanomas, either of the oral mucosa or cutaneous. On the other hand, most oral and cutaneous nevi were negative, with a few oral cases showing focal and weak expression. CONCLUSION Fatty acid synthase is expressed in malignant melanocytes, and it can be a helpful marker to distinguish oral melanomas from oral melanocytic nevi.


International Journal of Oral and Maxillofacial Surgery | 2009

Lingual cyst with respiratory epithelium: a histopathological and immunohistochemical analysis of two cases

Wilson Delagado Azañero; Renato Mazzonetto; Jorge Esquiche León; Pablo Agustin Vargas; M. A. Lopes; Op de Almeida

Cysts of the tongue are rare, usually derived from epithelia of the embryonic gastrointestinal and respiratory tracts, and classified according to the predominant epithelium lining. These cysts are usually discovered during infancy, more frequently in males, but they may not appear until well into adulthood. The authors report two lingual cysts lined mainly with respiratory, and focally by squamous, epithelium. Periodic acid-Schiff and mucicarmine staining revealed focal positivity in intracystic mucoid material and goblet cells. Immunohistochemical analysis with vimentin, cytokeratins (AE1/AE3, 34betaE12, CK1, CK5, CK6, CK7, CK8, CK10, CK13, CK14, CK16, CK18, and CK19), E-cadherin, beta-catenin, and epithelial membrane antigen showed a similar profile of normal respiratory epithelium, suggesting well-differentiated states. Owing to their controversial origin, these cysts should be named descriptively, as suggested by Manor et al., as lingual cysts with respiratory epithelium.


Oral Diseases | 2014

Malignant odontogenic tumors: a multicentric Latin American study of 25 cases.

M. Martínez Martínez; Adalberto Mosqueda-Taylor; Roman Carlos; Wilson Delgado-Azañero; Op de Almeida

OBJECTIVE The aim of this study was to show the epidemiological features of 25 malignant odontogenic tumors (MOT) in Latin America. MATERIALS AND METHODS We retrieved 25 cases of MOT out of 2142 odontogenic tumors, from four oral diagnostic centers in Latin America, and described the main clinical and pathological characteristics. RESULTS A total of 19 cases were carcinomas, including eight ameloblastic carcinomas, five primary intra-osseous squamous cell carcinomas, three clear cell odontogenic carcinomas and three ghost cell odontogenic carcinomas. All six sarcomas corresponded to ameloblastic fibrosarcoma. Thirteen cases occurred in men and 12 in women, age ranged from 7 to 77 years old, with a mean of 41.4 years. The average age of patients with carcinomas and sarcomas were 48.53 and 19 years old, respectively. CONCLUSION As malignant odontogenic tumors are very rare, this series helps to better clarify their relative frequency, predominant subtypes, and clinical characteristics in Latin America.


International Journal of Oral and Maxillofacial Surgery | 2009

Lichen sclerosus of the oral mucosa: clinicopathological features of six cases

Rebeca De Souza Azevedo; Mário José Romañach; Op de Almeida; Adalberto Mosqueda-Taylor; M.E. Vega-Memije; Roman Carlos-Bregni; Elisa Contreras-Vidaurre; P. López-Jornet; A. Saura-Inglés; Jacks Jorge

Lichen sclerosus is a chronic inflammatory mucocutaneous disease, rarely involving the mouth. There are only 20 well-documented cases of oral lichen sclerosus reported in the English-language literature. This report describes the clinicopathological features of 6 cases of oral lichen sclerosus; 5 in women. There were 12 lesions, mainly on the lips (50%) and buccal mucosa (25%). The affected areas appeared as irregular whitish patches, harder than the surrounding tissue. Half of the patients were symptomatic and presented with no associated skin and/or genital lesions. All cases were biopsied, and histopathological features were evaluated using hematoxylin-eosin and Verhoeffs stains, S-100 immunohistochemical reaction and transmission electron microscopy. Management of the oral lesions consisted of surgical excision, intralesional triamcinolone acetonide, oral colchicine, and regular follow-up. There is no effective curative treatment, but there are some options for patient management; and colchicine may be considered an additional choice.

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M. A. Lopes

State University of Campinas

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Pablo Agustin Vargas

State University of Campinas

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Jorge Esquiche León

State University of Campinas

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D.E.C. Perez

State University of Campinas

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Edgard Graner

State University of Campinas

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Fábio Ramôa Pires

State University of Campinas

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Jacks Jorge

State University of Campinas

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Jair Carneiro Leão

Federal University of Pernambuco

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Roman Carlos

Rio de Janeiro State University

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