Infecção pelo vírus Epstein-Barr tem influência sobre o desenvolvimento do carcinoma de laringe? Detecção de EBV pelo Real-Time Polymerase Chain Reaction em tecidos tumorais de pacientes com carcinoma de laringe / Does Epstein-Barr virus infection have an influence on the development of laryngeal carcinoma? Detection of EBV by Real-Time Polymerase Chain Reaction in tumour tissues of patients with laryngeal carcinoma

O vírus Epstein-Barr (EBV) é um conhecido vírus carcinogênico. A associação entre EBV e alguns tumores sugere que também pode haver correlação entre carcinoma de laringe e EBV. OBJETIVO: O presente estudo pretende determinar o papel do EBV na etiologia do carcinoma de laringe. MÉTODO: Estudo prospectivo sobre EBV por reação em cadeia da polimerase em tempo real em tecidos tumorais de 25 pacientes com carcinoma de laringe e 17 pacientes com lesões benignas de laringe; análise da relação entre presença de DNA viral e tabagismo, etilismo, localização e diferenciação tumoral. RESULTADOS: Não houve diferenças significativas entre os grupos de controle e de estudo para positividade da PCR para EBV (p > 0,05). Não foi identificada relação estatisticamente significativa entre positividade para EBV e diferenciação tumoral, localização da neoplasia, tabagismo ou etilismo (p > 0,05). CONCLUSÃO: Nossos resultados sugerem que, a despeito de sua identificação em alguns carcinomas espinocelulares de laringe, a presença de EBV não teve qualquer influência na patogenia do carcinoma de laringe.

Epstein-Barr virus (EBV) is a well-known carcinogenic virus, and the association of EBV with some tumours suggests that there may also be an association between laryngeal carcinoma and EBV. OBJECTIVE: The aim of this study is to determine the role of EBV in the aetiology of laryngeal carcinoma. METHOD: Prospective investigation the EBV with real time polymerase chain reaction in tumour tissues of 25 patients with laryngeal carcinoma and 17 patients with benign laryngeal lesions, and investigation of the relationship between the presence of viral DNA and patients' smoking habits, alcohol consumption, localization and differentiation of the tumour. RESULTS: There was no significant difference between the control group and patient group in terms of EBV polymerase chain reaction positivity (p > 0.05). Also we couldn't find a statistically significant relationship between EBV positivity and differentiation of the tumour, localization of the tumour, smoking and alcohol consumption habits (p > 0.05). CONCLUSION: Our results suggest that, although EBV is present in some of the squamous cell laryngeal carcinomas, its presence has no effect on the pathogenesis of laryngeal carcinomas.

Molecular investigation of a fungemia outbreak due to Candida parapsilosis in an intensive care unit

We investigated a nosocomial cluster of four Candida parapsilosis fungemia episodes that occurred in a neurological intensive care unit over a two-week period. The four infected patients had received parenteral nutrition through central lines, and all four had catheter-related candidemia. All of the isolates were susceptible to all of the antifungals tested, including amphotericin B, fluconazole, voriconazole, and caspofungin. They had strictly related fingerprints, based on randomly amplified polymorphic DNA analysis. Additional DNA sequencing data revealed that they were same strain. Although no isolate of Candida parapsilosis was recovered from other clinical, surveillance, or environmental samples, nosocomial spread of this yeast ceased, following the reinforcement of infection-control measures. Candida parapsilosis may require an intravascular foreign body to cause fungemia, but this outbreak shows that it can be transmitted nosocomially and can cause epidemics.

Expression of cell surface markers on methicillin resistant Staphylococcus aureus stimulated lymphocytes.

BACKGROUND & OBJECTIVE: Methicillin-resistant Staphylococcus aureus (MRSA) has gradually been increasing, new strategies in the treatment of MRSA infections are required. This depends on the understanding of the infection pathogenesis and the immune response. This study was therefore designed to determine the immune response which develops during MRSA infection and the role of chemokines in this response, and also to compare the results with the changes occurring after MSSA infection. METHODS: The expression of the surface markers of human lymphocytes stimulated by heat-killed MRSA or MSSA was analysed by flow cytometry. The chemokine levels in the lymphocytes culture supernatants stimulated or not stimulated by microorganisms were determined by ELISA. RESULTS: Human peripheral blood mononuclear cells (PBMCs) stimulated by MRSA the levels of CD4(+)CD25(+) regulatory T cells, CD69 expressions in the activated T lymphocytes, CD3(-)CD16(+)CD56(+) NK cells and the levels of MIP-1alpha, MIP-1beta, MCP-1 chemokines increased as compared to the cells not stimulated by MRSA. Although stimulation by MSSA caused an increase in CD25 expression after 24 h, the increase was found to be lower than the one caused by MRSA stimulation. The increase in CD69 expression was statistically significant compared to the cells stimulated by MRSA. Different from the cells stimulated by MRSA, no change was observed in the expressions of CD54 and CD3(-)CD16(+)CD56(+) NK cells in the cells stimulated by MSSA. INTERPRETATION & CONCLUSION: Our findings showed that cellular as well as humoral immunity are critical in MRSA infection and that T cell activation and the increase in chemokines may play a role in the regulation of immune response.

The effects of fluconazole and cytokines on human mononuclear cells

Candida infections are common infections and fluconazole is one of the most frequently administered antifungal agents in their treatment. The resistance developed against antifungal agents has necessitated the improvement of new treatments. This study focuses on the investigation of the effect of fluconazole and cytokines such as interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), granulocyte-macrophage colony-stimulating factor (GM-CSF) on chemokine production and anticandidal activity of human monocytes. In the study it was observed that GM-CSF caused an increase in candidacidal activity of monocytes. Anticandidal activity of GM-CSF + IFN-gamma combination was not found to be more effective than GM-CSF or IFN-gamma alone. The presence of cytokine and fluconazole caused an increase in the levels of CCL3 and CCL4 chemokines. Accordingly, it was considered that chemokines could contribute to the efficacy of fluconazole in C. albicans infections. Besides, in order to strengthen the immune system some cytokines might be used in addition to antifungal agents for the treatment.

Evaluation of the natural killer cytotoxicity and the levels of cytokines in rats with type I diabetes mellitus

Type I diabetes mellitus (insulin-dependent DM = IDDM) is a chronic disease characterized by specific destruction of pancreatic beta cells, resulting in an absolute lack of insulin. Immune mechanisms, genetic susceptibility, and environmental factors are all implicated in the pathogenesis of Type 1 diabetes. This study was aimed at determining the efficiency of cytokines, natural killer (NK) cells in the pathophysiology of IDDM. Therefore, we evaluated the plasma levels of cytokines by specific enzyme-linked immunosorbent assay (ELISA) and the cytotoxicity activity of NK cells by anti-candididal index in rats with type I diabetes. We found that the cytotoxicity activity of NK cells in IDDM groups significantly decreased compared to the control groups. The levels of interferon-g (IFN-g) in IDDM groups were slightly higher than in healthy controls. These results indicate that the changes of T H1 type cytokines such as IFN-g and NK cell activity can play a role in the etiology of IDDM. The data may provide new strategies for the treatment of IDDM.