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101.
102.
Over-expression of DNA methyltransferases DNMT1, DNMT3a and DNMT3b has been reported in various cancers and precancerous lesions.
Objective
To investigate DNMT1, DNMT3a and DNMT3b enzymes in oral squamous cell carcinoma (SCC) and leukoplakia, and their relationship with histopathologic/clinical parameters.Study design
Immunohistochemistry was carried out to evaluate the three DNMTs in 60 samples of oral SCC and 37 samples of oral leukoplakia.Results
DNMT3a immunoreactivity in the three groups of oral SCC (39.8%) was significantly higher than in control (22.6%) (ANOVA, Student–Newman–Keuls test, P < 0.05), but not when compared to oral leukoplakia groups (28.2%). For DNMT1 and DNMT3b, there were no statistically significant differences between oral SCC groups (65% and 74.7%), oral leukoplakia groups (68.3% and 70.9%) and control (65.4% and 76.5%). There was a significantly higher mean percentage of DNMT1 immunoreactivity in non-smokers (ANOVA, P = 0.048), and a higher DNMT3a immunoreactivity in alcohol users (ANOVA, P = 0.01).Conclusions
Higher DNMT3a immunopositivity may be associated with oral SCC and alcohol use, whilst lower levels of DNMT1 may be related with smoking habit. However, there was a significantly higher mean percentage of DNMT1 immunoreactivity in non-smokers (ANOVA, P = 0.048), and a higher DNMT3a immunoreactivity in alcohol users (ANOVA, P = 0.010). 相似文献103.
Atilano ML Pereira PM Yates J Reed P Veiga H Pinho MG Filipe SR 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(44):18991-18996
The cell wall of Staphylococcus aureus is characterized by an extremely high degree of cross-linking within its peptidoglycan (PGN). Penicillin-binding protein 4 (PBP4) is required for the synthesis of this highly cross-linked peptidoglycan. We found that wall teichoic acids, glycopolymers attached to the peptidoglycan and important for virulence in Gram-positive bacteria, act as temporal and spatial regulators of PGN metabolism, controlling the level of cross-linking by regulating PBP4 localization. PBP4 normally localizes at the division septum, but in the absence of wall teichoic acids synthesis, it becomes dispersed throughout the entire cell membrane and is unable to function normally. As a consequence, the peptidoglycan of TagO null mutants, impaired in wall teichoic acid biosynthesis, has a decreased degree of cross-linking, which renders it more susceptible to the action of lysozyme, an enzyme produced by different host organisms as an initial defense against bacterial infection. 相似文献
104.
R. Filipe A. Mota C. Bastos A. Figueiredo B. Parada P. Nunes 《Transplantation proceedings》2009,41(3):843-845
The purpose of this study was to assess the impact of a corticosteroid-free maintenance immunosuppression on graft survival in kidney transplantation. We analyzed 79 patients who were transplanted between June 1, 2006 and May 31, 2007. We excluded hyperimmunized patients, second transplantations, living donors, and black recipients. Patients underwent induction with thymoglobulin or basiliximab, followed by treatment with mycophenolate mofetil (MMF), tacrolimus, and methylprednisolone. On the 5th day, the patients were divided into 2 groups: group A (n = 45) discontinued steroid therapy; group B (n = 34) continued prednisone therapy. We performed a comparative analysis of incidence of delayed graft function (DGF), acute rejection episodes (ARE), renal function at 6 and 12 months, graft and patient survivals, causes of graft loss, and mortality. The 2 groups were similar for donor, recipient, and graft characteristics. The incidences of DGF were 8.9% in group A and 14.7% in group B; those for ARE were 2.3% in group A and 13.8% in group B (P = .077). The mean serum creatinine levels at 6 and 12 months were similar. There were 8 graft losses: 3 in group A (3 deaths with functioning grafts) and 5 in group B (1 death, 3 vascular causes, 1 kidney nonfunction). The 4 deaths were due to infection (n = 3) or neoplasia (n = 1). Graft survivals at 1 year were 98% in group A and 85% in group B, and patient survivals were 98% and 97%, respectively. An immunosuppressive regimen using antibody induction and steroid-free treatment proved to be effective in low-risk patients. 相似文献
105.
Couto PA Filipe VM Magalhães LG Pereira JE Costa LM Melo-Pinto P Bulas-Cruz J Maurício AC Geuna S Varejão AS 《Journal of neuroscience methods》2008,173(2):193-200
Of all the detrimental effects of spinal cord injury (SCI), one of the most devastating effects is the disruption of the ability to walk. Therefore, much effort has been focused on developing several methods to document the recovery of locomotor function after experimental SCI. Computerized rat gait analysis is becoming increasingly popular in the SCI research community. The two-dimensional (2D) kinematic approach is by far the most popular technique in rat gait analysis. This is a simple inexpensive procedure, which requires only one camera to record the movement. Our study included an examination of locomotion on a treadmill using 2D and three-dimensional (3D) analysis, in neurologically intact animals and following moderate T9 contusion injury. Despite the overall time course patterns of the curves were identical, we found significant differences between values of the 2D and 3D joint angular motion. In conclusion, maximal precision and accuracy of the kinematic values are expected when the experimental protocol includes a 3D motion analysis methodology. Moreover, a 2D method cannot be used to determine the external or internal rotations of the foot because this movement occurs in the transverse plane. 相似文献
106.
Aldini Beuting Pereira Kitahara Arieli Carini Michels Suelen Teixeira Luiz Seigo Nagashima Ana Paula Camargo Martins Marina Luise Viola de Azevedo Luciana Reis Azevedo Alanis Paulo Henrique Couto Souza Sérgio Aparecido Ignácio Lucia de Noronha Patrícia Vida Cassi Bettega Maria Carolina Albini Tyski Edinson Manuel Pérez Quispe Izabela Mozzer Giovanna Ribeiro Souto Maria Cássia Ferreira Aguiar Filipe Modolo Rafaela Scariot Bruno Correia Jham Ana Maria Trindade Grégio Hardy Aline Cristina Batista Rodrigues Johann 《Oral diseases》2023,29(2):376-379
107.
Sevdenur Cizginer MD MPH Eian G. Prohl MD Joao Filipe G. Monteiro PhD Ferhat Yildiz MD Richard N. Jones ScD Steven Schechter MD Robert Patterson MD Adam Klipfel MD Mark Richard Katlic MD MMM Lori A. Daiello PharmD ScM Nadia Mujahid MD Iva Neupane MD William G. Cioffi MD Maria Ducharme DNP RN Matthew D. Vrees MD Lynn McNicoll MD 《Journal of the American Geriatrics Society》2023,71(5):1452-1461
108.
Samões Beatriz Guimarães da Fonseca Diogo Beirão Tiago Costa Flávio Vieira Romana Terroso Georgina Ferreira Raquel Miriam Nicolau Rafaela Saraiva André Salvador Maria João Duarte Ana Catarina Cordeiro Ana Vilas-Boas João Paulo Genrinho Inês Bento da Silva Ana Gago Laura Resende Catarina Martins Patricia Madeira Nathalie Dinis Sara Couto Maura Santos Inês Araújo Filipe Mourão Ana Filipa Gomes Guerra Miguel Oliveira Margarida Daniel Alexandra Rodrigues Marília Dantas Soares Catarina Parente Hugo Furtado Carolina Fontes Tomás Abelha-Aleixo Joana 《Clinical rheumatology》2023,42(8):2125-2134
Clinical Rheumatology - The study aims to define the clinical and subclinical calcinosis prevalence, the sensitivity of radiographed site and clinical method for its diagnosis, and the phenotype of... 相似文献
109.
Pinho S Marcos NT Ferreira B Carvalho AS Oliveira MJ Santos-Silva F Harduin-Lepers A Reis CA 《Cancer letters》2007,249(2):157-170
The activation of an abnormal glycosylation pathway in cancer cells leads to the formation of the sialyl-Tn antigen, blocking regular carbohydrate chain elongation. Sialyl-Tn antigen is rarely expressed in normal tissues but is aberrantly expressed in a variety of carcinomas, where it constitutes a marker of poor prognosis. Although the clinical significance of sialyl-Tn is well characterized, a functional role for this glycan and its contribution to cancer progression remain to be elucidated. This study evaluates the capability of sialyl-Tn to modify processes like cell cycle, apoptosis, actin cytoskeleton dynamics, adhesion and motility on ECM components, cell-cell aggregation and invasion. De-novo expression of sialyl-Tn leads to major morphological and cell behavior alterations in gastric carcinoma cells which were reverted by specific antibody blockage. Sialyl-Tn antigen is able to modulate a malignant phenotype inducing a more aggressive cell behavior, such as decreased cell-cell aggregation and increased ECM adhesion, migration and invasion. 相似文献
110.