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91.
Andressa Kelly Alves Ferreira Srgio Henrique Gonalves de Carvalho Ana Flvia Granville-Garcia Dmitry Jos de Santana Sarmento Gustavo Gomes Agripino Mauro Henrique Nogueira Guimares de Abreu Maria Cecília Freire de Melo Arnaldo de Frana Caldas Jr Gustavo Pina Godoy 《Medicina oral, patología oral y cirugía bucal》2021,26(3):e387
Background This study aimed to evaluate sociodemographic and clinical factors influencing overall survival (OS) in patients with oral squamous cell carcinoma (OSCC). Material and Methods Medical charts of 547 patients with OSCC from a public hospital in northeastern Brazil seen between 1999 and 2013 were evaluated. Survival analysis was performed using the Kaplan-Meier method. The influence of age, sex, ethnicity, clinical stage, anatomical location, type of treatment, and comorbidities on the patients’ prognosis was evaluated. Cox proportional hazards regression model was used to identify independent prognostic factors. Results The 5-year OS was 39%. Multivariate analysis showed that age < 40 years (HR = 2.20; 95%CI: 1.02-4.72) and a single treatment modality (HR = 1.91; 95%CI: 1.37-2.67) were associated with a poor prognosis, while early clinical stage resulted in better outcomes (HR = 0.38; 95%CI: 0.25-0.58). Conclusions OSCC patients in advanced clinical stages, diagnosed at a younger age, and submitted to a single therapeutic modality have a poorer prognosis. Key words:Head and neck cancer, oral cancer, oral squamous cell carcinoma, survival, prognosis. 相似文献
92.
Breno Bittencourt de Brito Fabian Fellipe Bueno Lemos Caroline da Mota Carneiro ressa Santos Viana Nilo Manoel Pereira Vieira Barreto Gabriela Alves de Souza Assis Barbara Dicarlo Costa Braga Maria Lu sa Cordeiro Santos Filipe Ant nio Fran a da Silva Hanna Santos Marques Nat lia Oliveira e Silva Fabr cio Freire de Melo 《World Journal of Meta-Analysis》2021,9(3):257-276
Gastric adenocarcinoma is a global health concern, and Helicobacter pylori (H. pylori) infection is the main risk factor for its occurrence. Of note, the immune response against the pathogen seems to be a determining factor for gastric oncogenesis, and increasing evidence have emphasized several host and bacterium factors that probably influence in this setting. The development of an inflammatory process against H. pylori involves a wide range of mechanisms such as the activation of pattern recognition receptors and intracellular pathways resulting in the production of proinflammatory cytokines by gastric epithelial cells. This process culminates in the establishment of distinct immune response profiles that result from the cytokine-induced differentiation of T naïve cells into specific T helper cells. Cytokines released from each type of T helper cell orchestrate the immune system and interfere in the development of gastric cancer in idiosyncratic ways. Moreover, variants in genes such as single nucleotide polymorphisms have been associated with variable predispositions for the occurrence of gastric malignancy because they influence both the intensity of gene expression and the affinity of the resultant molecule with its receptor. In addition, various repercussions related to some H. pylori virulence factors seem to substantially influence the host immune response against the infection, and many of them have been associated with gastric tumorigenesis. 相似文献
93.
Amorim dos Santos Juliana Normando Ana Gabriela Costa de Toledo Isabela Porto Melo Gilberto De Luca Canto Graziela Santos-Silva Alan Roger Guerra Eliete Neves Silva 《Clinical oral investigations》2020,24(1):37-45
Clinical Oral Investigations - To evaluate therapeutic effects of laser therapy on patients with recurrent aphthous stomatitis assessing evidences from previously published systematic reviews. An... 相似文献
94.
Coelho Daniel Gomes Marinato Claudio Sérgio de Matos Letícia Paiva de Andrade Heloísa Monteiro da Silva Vinicius Melo Santos-Neves Pedro Henrique Araújo Samuel Coelho Oliveira Juraci Alves 《Ecotoxicology (London, England)》2020,29(2):196-202
Ecotoxicology - In order to evaluate the differential absorption and toxicity of arsenate (AsV) and arsenite (AsIII), Lemna valdiviana plants were grown in a nutrient solution and subjected to 0.0... 相似文献
95.
Paulo Ernando Ferraz Cavalcanti Michel Pompeu Barros de Oliveira Sá Cecília Andrade dos Santos Isaac Melo Esmeraldo Mariana Leal Chaves Ricardo Felipe de Albuquerque Lins Ricardo de Carvalho Lima 《Brazilian Journal Of Cardiovascular Surgery》2015,30(2):148-158
Objective
To determine whether stratification of complexity models in congenital heart surgery (RACHS-1, Aristotle basic score and STS-EACTS mortality score) fit to our center and determine the best method of discriminating hospital mortality.Methods
Surgical procedures in congenital heart diseases in patients under 18 years of age were allocated to the categories proposed by the stratification of complexity methods currently available. The outcome hospital mortality was calculated for each category from the three models. Statistical analysis was performed to verify whether the categories presented different mortalities. The discriminatory ability of the models was determined by calculating the area under the ROC curve and a comparison between the curves of the three models was performed.Results
360 patients were allocated according to the three methods. There was a statistically significant difference between the mortality categories: RACHS-1 (1) - 1.3%, (2) - 11.4%, (3)-27.3%, (4) - 50 %, (P<0.001); Aristotle basic score (1) - 1.1%, (2) - 12.2%, (3) - 34%, (4) - 64.7%, (P<0.001); and STS-EACTS mortality score (1) - 5.5 %, (2) - 13.6%, (3) - 18.7%, (4) - 35.8%, (P<0.001). The three models had similar accuracy by calculating the area under the ROC curve: RACHS-1- 0.738; STS-EACTS-0.739; Aristotle- 0.766.Conclusion
The three models of stratification of complexity currently available in the literature are useful with different mortalities between the proposed categories with similar discriminatory capacity for hospital mortality. 相似文献96.
97.
Hypoxia-regulated therapeutic gene as a preemptive treatment strategy against ischemia/reperfusion tissue injury 总被引:4,自引:0,他引:4 下载免费PDF全文
Pachori AS Melo LG Hart ML Noiseux N Zhang L Morello F Solomon SD Stahl GL Pratt RE Dzau VJ 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(33):12282-12287
Ischemia and reperfusion represent major mechanisms of tissue injury and organ failure. The timing of administration and the duration of action limit current treatment approaches using pharmacological agents. In this study, we have successfully developed a preemptive strategy for tissue protection using an adenoassociated vector system containing erythropoietin hypoxia response elements for ischemia-regulated expression of the therapeutic gene human heme-oxygenase-1 (hHO-1). We demonstrate that a single administration of this vector several weeks in advance of ischemia/reperfusion injury to multiple tissues such as heart, liver, and skeletal muscle yields rapid and timely induction of hHO-1 during ischemia that resulted in dramatic reduction in tissue damage. In addition, overexpression of therapeutic transgene prevented long-term pathological tissue remodeling and normalized tissue function. Application of this regulatable system using an endogenous physiological stimulus for expression of a therapeutic gene may be a feasible strategy for protecting tissues at risk of ischemia/reperfusion injury. 相似文献
98.
Maciel TT Melo RS Schor N Campos AH 《Journal of molecular and cellular cardiology》2008,44(2):370-379
Recent reports highlight the importance of BMP in the vasculature. We investigated the expression pattern and role of the BMP antagonist gremlin in VSMC. We detected gremlin mRNA constitutive expression in adult and embryonic rat aortic VSMC, and in rat carotids. In vitro analysis demonstrated that angiotensin II, TGF-β1 and PDGF induced significant changes in gremlin mRNA expression. Gremlin stable overexpression in A7r5 cells blocked BMP signaling. BMP-induced reduction in VSMC DNA synthesis was markedly inhibited by gremlin overexpression. In fact, gremlin overexpression increased DNA synthesis and cell counts, and accelerated cell cycle progression of VSMC, through mechanisms that include p27kip1 down-regulation. Gremlin also led to marked increments in VSMC migration. In addition, gremlin gene silencing promoted a significant blockade on cell proliferation and migration. In vivo studies disclosed increased gremlin protein expression in the neointima of balloon-injured carotid arteries. In summary, the BMP antagonist gremlin is constitutively expressed in the normal vasculature. Gremlin induces VSMC proliferation and migration and is significantly regulated by growth factors and injury. We postulate that gremlin plays a part in the development of pathological phenotypic changes of adult VSMC. 相似文献
99.
100.
Implementation of evidence‐based dentistry into practice: analysis of awareness,perceptions and attitudes of dentists in the World Dental Federation–European Regional Organization zone 下载免费PDF全文
Nermin Yamalik Secil Karakoca Nemli Eunice Carrilho Simona Dianiskova Paulo Melo Anna Lella Joel Trouillet Vladimer Margvelashvili 《International dental journal》2015,65(3):127-145
Based on evidence‐based dentistry (EBD) being a relatively new concept in dentistry, the attitudes, perceptions and level of awareness of dentists regarding EBD, and perceived barriers to its implementation into daily practice, were comparatively analysed in six countries of the FDI (World Dental Federation‐Federation Dentaire Internationale)‐European Regional Organization (ERO) zone (France, Georgia, Poland, Portugal, Slovakia and Turkey). For this purpose, a questionnaire, ‘The Relationship Between Dental Practitioners and Universities’, was developed by the FDI‐ERO Working Group and applied by National Dental Associations (NDAs). A total of 850 valid responses were received, and cumulative data, comparisons between countries and potential impact of demographic variables were analysed. Regarding EBD, similar percentages of respondents reported that they ‘know what it is’ (32.8%) and ‘they practice’ (32.1%). Most respondents believed that ‘EBD is beneficial’ (89.1%); however, they had different thoughts regarding ‘who actually benefited from EBD’. Of the participants, 60% believed that ‘dentists experience difficulties in implementing EBD’. Although lack of time, lack of education and limited availability of evidence‐based clinical guidelines were among the major barriers, there were differences among countries (P < 0.05). Significant differences were also observed between countries regarding certain questions such as ‘where EBD needed to be taught’ (P < 0.05), as both undergraduate and continuing education were suggested to be suitable. Age, practice mode and years of practice significantly affected many of the responses (P < 0.05). There was a general, positive attitude toward EBD; however, there was also a clear demand for more information and support to enhance dentists’ knowledge and use of EBD in everyday practice and a specific role for the NDAs. 相似文献