OBJECTIVES: The aim of this study was to examine the expression of the N-myc downstream-regulated gene 1 protein in benign and malignant lesions of the thyroid gland by immunohistochemistry. INTRODUCTION: N-myc downstream-regulated gene 1 encodes a protein whose expression is induced by various stimuli, including cell differentiation, exposure to heavy metals, hypoxia, and DNA damage. Increased N-myc downstream-regulated gene 1 expression has been detected in various types of tumors, but the role of N-myc downstream-regulated gene 1 expression in thyroid lesions remains to be determined. METHODS: A tissue microarray paraffin block containing 265 tissue fragments corresponding to normal thyroid, nodular goiter, follicular adenoma, papillary thyroid carcinoma (classical pattern and follicular variant), follicular carcinoma, and metastases of papillary and follicular thyroid carcinomas were analyzed by immunohistochemistry using a polyclonal anti- N-myc downstream-regulated gene 1 antibody. RESULTS: The immunohistochemical expression of N-myc downstream-regulated gene 1 was higher in carcinomas compared to normal thyroid glands and nodular goiters, with higher expression in classical papillary thyroid carcinomas and metastases of thyroid carcinomas (P < 0.001). A combined analysis showed higher immunohistochemical expression of NDRG1 in malignant lesions (classical pattern and follicular variant of papillary thyroid carcinomas, follicular carcinomas, and metastases of thyroid carcinomas) compared to benign thyroid lesions (goiter and follicular adenomas) (P = 0.043). In thyroid carcinomas, N-myc downstream-regulated gene 1 expression was significantly correlated with a more advanced TNM stage (P = 0.007) and age, metastasis, tumor extent, and size (AMES) high-risk group (P = 0.012). CONCLUSIONS: Thyroid carcinomas showed increased immunohistochemical N-myc downstream-regulated gene 1 expression compared to normal and benign thyroid lesions and is correlated with more advanced tumor stages.

Tumores de glândulas salivares apresentam características histopatológicas altamente heterogêneas. Existem poucos estudos epidemiológicos analisando um número elevado de tumores de glândulas salivares benignos e malignos no Brasil. MATERIAL E MÉTODOS: Revisamos os prontuários hospitalares de 124 pacientes com tumores de glândulas salivares durante o período de Janeiro de 1993 até Dezembro de 1999. Os pacientes foram analisados de acordo com o sexo, idade, tamanho do tumor, localização e tipo histopatológico. RESULTADOS E CONCLUSÕES: Pacientes com tumores benignos e malignos apresentaram uma média de idade de 47,7 e 48,8 anos, respectivamente. A freqüência de ocorrência dos tumores benignos foi de 80% (n=99) e dos tumores malignos de 20% (n=25). Tumores foram localizados na parótida em 71% (n=88) dos casos, na glândula submandibular em 24% (n=30), e glândulas salivares menores em 5% (n=6). Os principais tumores benignos foram o Adenoma Pleomórfico que representou 84% (n=84) dos casos e o Tumor de Warthin com 13% (n=13) dos casos. Entre os tumores malignos, o Carcinoma Mucoepidermóide foi o mais comum correspondendo a 52% dos casos (n=13), seguido pelo Carcinoma Adenóide Cístico em 20% (n=5) e Carcinoma ex Adenoma Pleomórfico que foi detectado em 12% dos casos (n=3).

Salivary gland tumors constitute a highly heterogeneous histopathologic group. There are few epidemiological studies of large series of benign and malignant salivary gland tumors in Brazil. MATERIAL AND METHODS: Hospital records of 124 patients with salivary gland tumors diagnosed from January 1993 to December 1999 were reviewed. The patients were analyzed according to gender, age, size, location, and histopathology of the tumor. RESULTS AND CONCLUSIONS: Patients with benign and malignant tumors presented with a mean age of 47.7 and 48.8 years, respectively. The frequency of benign tumors was 80% (n = 99) and malignant tumors 20% (n = 25). Tumors were localized in the parotid gland 71% (n = 88), in the submandibular gland 24% (n = 30), and in the minor salivary glands 5% (n = 6). The most common benign tumors were pleomorphic adenoma in 84% (n = 84) and Warthin's tumor in 13% (n = 13). Among malignant tumors, mucoepidermoid carcinoma was the most common in 52% (n = 13), adenoid cystic carcinoma occurred in 20% (n = 5), and carcinoma ex pleomorphic adenoma was detected in 12% (n = 3).

O objetivo deste estudo foi o de quantificar a distribuição dos sistemas de fibras elásticas encontrados na parede da artéria cerebral anterior. O estudo foi baseado nos trabalhos de Glynn (1940) e Stehbens (1989) referentes a incidência e origem dos aneurismas cerebrais e estudos recentes sobre fibras elásticas. A artéria cerebral anterior foi dividida em três segmentos S1, S2 e S3; S1 corresponde ao segmento de origem da artéria cerebral anterior, S2 localizado entre a junção da artéria com o ramo comunicante anterior, e S3 ao segmento arterial ao nível da junção do rostro e joelho do corpo caloso; todos estes foram submetidos a procedimentos histológicos rotineiros . Foi realizado estudo histomorfométrico calculando-se a densidade linear dos componentes do sistema de fibras elásticas , que avalia o comprimento total de cada tipo de fibra em cada segmento analisado. Os dados obtidos foram calculados e as duas variáveis idade e densidade linear foram tratadas e correlacionadas estatisticamente através de métodos de regressão linear. Os resultados mostram de maneira geral um aumento da quantidade de fibras do sistema elástico com a idade e uma distribuição não homogênea destes sistemas na túnica média da artéria cerebral anterior. As fibras elaunínicas no entanto diminuem com a idade, sugerindo menor elasticidade do sistema, principalmente no segmento intermediário.

The aim of the present study was to quantify the distribution of the elastic fiber system within the wall of the anterior cerebral artery. The study is based on the works of Glynn (1940) and Stehbens (1989) concerning the incidence and origin of brain aneurysms and recent studies of the elastic fibers. The anterior cerebral artery was divided into three segments, S1, S2 and S3: S1 corresponds to the origin of the anterior cerebral artery, S2 is located at the junction of the anterior cerebral artery with the anterior communicating artery, and S3 at the junction of the rostrum and genu of the corpus callosum,which were submitted to routine histological procedures. A histomorphometrical study was undertaken using an estimation of the linear density (Ld) of the components of the fibrous elastic system which evaluates their full length in each segment. Data were analyzed using first order linear regression methods. The results show a decreasing quantity of elastic fibers in the three segments (S1>S2>S3). Study of the elastic fiber system may originate new concepts regarding the genesis of cerebral artery aneurysm.