PDT was effective as a bactericidal agent in Enterococcus faecalis-contaminated root canals.

a b s t r a c tCONTEXT: Among the cytological and morphological properties of mucoepidermoid carcinoma, one of the most important criteria for measuring its biological behavior and aggressiveness is cell proliferation. In this way, immunohistochemical markers of cell proliferation have been found to be useful in tumor classification and have formed part of the prognostic and therapeutic studies of these pathologies. OBJECTIVE:To analyze 11 cases of mucoepidermoid carcinoma (MEC) using the proliferation activity marker (PCNA) and to determine its relationship to the grade of malignancy of these tumors.DESIGN: Correlation study. SETTING:Head and Neck Surgery Service of Heliópolis Hospital, São Paulo, Brazil. SAMPLE:Slides of 11 cases of primary mucoepidermoid carcinomas of salivary glands were prepared according to routine techniques employed in the Oral Pathology Department of the Dentistry Faculty of São Paulo University, Brazil. They were fixed in a 10% formaldehyde solution and stained with hematoxylin and eosin. After this preparation the tumors were classified as low, intermediate and high grade of malignancy, according to the criteria established by Seifert & Sobin and Auclair, Goode & Ellis. The slides were sent for immunohistochemical processing to evaluate the positivity of proliferating cell nuclear antigen using the streptavidin biotin technique. MAIN MEASUREMENT:The correlation between proliferating cell nuclear antigen expression and the histological malignancy grade in mucoepidermoid carcinoma of salivary glands. RESULTS:there were 4 cases (36%) of low grade, 4 cases (36%) of intermediate grade and 3 cases (27%) of high grade of malignancy. After a comparative study between histological features and immunohistochemical analysis, significant differences were observed (P < 0.01) for low, intermediate and high grades: 16.04%, 26.98% and 56.98% of proliferating cell nuclear antigen expression in mucoepidermoid carcinoma , respectively. CONCLUSION:The proliferating cell nuclear antigen expression increases with the grade of malignancy in mucoepidermoid carcinoma of salivary glands.

The dissemination of the practice of collaborative authorship (co-authorship) in Brazil and in the international scientific community has been accompanied by an increasing occurrence of frauds, manipulations and other deviations in the assignment of responsibility for a scientific paper. This article discusses the criteria for authorship attribution, the reasons for the growing indices of co-authorship and the challenges to determine authorship in electronic journals. Through literature review and case study (bibliographic search in the scientific database), it has been shown ways to avoid that "misbehaviour" deviance regarding the authorship attribution affect the credibility of science.Descriptors: Authorship. Periodicals. Scientific communication. Scientific production. ResumoA disseminação da prática de coautoria no Brasil e na comunidade internacional tem sido acompanhada pelo aumento no registro de fraudes, manipulações e outros desvios ao definir a responsabilidade por um trabalho científico. Este artigo discorre sobre os critérios utilizados para atribuição da autoria, as razões para o crescimento dos índices de coautoria e os desafios para estabelecer a autoria em periódicos eletrônicos. Por meio de revisão bibliográfica e estudo de caso (a partir de levantamento de base de dados), aponta caminhos para evitar que "desvios de comportamento" quanto à atribuição de autoria abalem a credibilidade da ciência.Descritores: Autoria. Publicações periódicas. Comunicação científica. Produção científica.

The assessment of depressive behaviour in chronic pain patients is especially important, because depression is commonly associated with chronic pain. The aim of this pilot study was to compare depression levels between patients with head and neck cancer pain and temporomandibular disorders (TMD), and to determine whether there is an association between depression levels and chronic pain severity. This study was an observational and sectional study and the sample consisted of 40 patients, uniformly divided into those with chronic orofacial pain related to cancer and those with painful TMD classified with research diagnostic criteria for temporomandibular disorders (RDC/TMD) axis I. Depression levels, pain intensity and severity were assessed with RDC/TMD axis II. The study demonstrated statistically significant differences in depression levels present in the head and neck cancer pain group and the painful TMD group, with the occurrence of a moderate statistically significant correlation between depression levels and chronic pain severity.