Evaluation of the Erythrocyte Membrane in Head and Neck Cancer Patients.

Head and neck squamous cell carcinoma (HNSCC) is a heterogeneous and complex disease, both from a clinical and molecular point of view. The prolonged use of alcohol and tobacco, along with the release of tumor secretions can modulate blood cells, such as erythrocytes. Here, this study was conducted with 24 patients diagnosed with HNSCC and an equal number of healthy individuals are matched by age and gender. The levels of lipid peroxidation were measured using the individual plasma, while for lipid concentrations, identification and quantification Na, K-ATPase activity and osmotic fragility, the red blood cell concentrate were used. The release of TBARS was significantly higher in patients with HNSCC. The lipid profile assays demonstrated a rearrangement of the erythrocyte membrane due to a decrease in total phospholipids and phosphatidylethanolamine followed by an increase in total cholesterol and phosphatidylcholine. Na, K-ATPase activity also increased. Erythrocytes were more fragile in patients with HNSCC than in health individuals. Therefore, the membrane of erythrocytes were rearranged and Na, K-ATPase function altered in the HNSCC patients. Our findings suggests that the alcohol, tobacco and tumor secretion modulate in a specific manner that the erythrocytes membranes of these patients making this system a potential tool for HNSCC biomarker of tumor progression.

Could Na,K-ATPase play a role in potassium leakage from irradiated erythrocytes?

BACKGROUND: In developing countries, the access to red blood cell (RBC) irradiators is restricted. Thus, it is a common practice in blood banks to stock irradiated RBC units until they expire. The aim of this work is to elucidate the involvement of Na,K-ATPase in potassium leakage from prophylactically irradiated RBCs. METHODS: Whole blood was collected from healthy donors, and blood concentrates were irradiated with 25Gy of γ-radiation within 24h of collection. At days 3, 5, 7, 9, 11, 14 and 28 post-irradiation, fractions were removed and centrifuged and Na,K-ATPase activity from ghost membranes was determined. RESULTS: The inhibition of Na,K-ATPase activity in RBCs reached 12.6% by day 7 of storage and up to 50% by day 14 of storage. The addition of vitamin C prevented the irradiation-induced loss of Na,K-ATPase activity. The irradiation of RBCs provoked an increase in potassium plasma levels and a decrease in sodium plasma levels. The incubation of RBCs with ouabain did not change the sodium or potassium levels in the plasma, and the addition of vitamin C only partially prevented a decrease in sodium levels caused by irradiation. CONCLUSION: Because the inhibition of Na,K-ATPase by ouabain did not cause potassium accumulation in the plasma, we conclude that the irradiation-induced inhibition of the pump is not a key factor driving this effect.

Câncer de boca: avaliação do conhecimento e conduta dos dentistas na atenção primária à saúde / Oral cancer: assessment of knowledge and conduct of dentists in primary health care

O câncer de boca representa um problema de saúde pública devido aos diagnósticos tardios e das taxas de morbimortalidade. Esse estudo avaliou o nível de conhecimento dos odontólogos (23) da atenção primária da rede pública de Divinópolis (MG) sobre o câncer bucal. Empregou-se questionário estruturado e os dados obtidos demonstraram que 39,1% dos entrevistados não sabiam qual o tipo mais comum de câncer de boca; 35% avaliaram seu nível de conhecimento como bom ou ótimo. Fatores de risco apontados: uso do tabaco, antecedentes familiares, uso do álcool e exposição solar. Apenas 13% receberam treinamento para o exame de câncer bucal na graduação. Esses achados reforçam a necessidade de abordagem do tema no período de formação acadêmica e de educação continuada.

Oral cancer represents a major public health problem due to high rates of late diagnoses and significant morbidity and mortality rates. This study assessed the level of knowledge of active dentists (23) in primary care in public health at Divinópolis (MG) on oral cancer. A structured questionnaire was used. The data showed that 39.1% of respondents didn`t know what the most common type of oral cancer, 35% rated their level of knowledge as good or great. Tobacco use, family history, alcohol use and sun exposure were the most likely risk factors mentioned. Only 13% received training for oral cancer exam on graduation. These findings reinforce the need for a greater approach regarding the theme during academic training and continuing education.