Radiation induced apoptosis and initial DNA damage are inversely related in locally advanced breast cancer patients.

Background. DNA-damage assays, quantifying the initial number of DNA double-strand breaks induced by radiation, have been proposed as a predictive test for radiation-induced toxicity. Determination of radiation-induced apoptosis in peripheral blood lymphocytes by flow cytometry analysis has also been proposed as an approach for predicting normal tissue responses following radiotherapy. The aim of the present study was to explore the association between initial DNA damage, estimated by the number of double-strand breaks induced by a given radiation dose, and the radio-induced apoptosis rates observed. Methods. Peripheral blood lymphocytes were taken from 26 consecutive patients with locally advanced breast carcinoma. Radiosensitivity of lymphocytes was quantified as the initial number of DNA double-strand breaks induced per Gy and per DNA unit (200 Mbp). Radio-induced apoptosis at 1, 2 and 8 Gy was measured by flow cytometry using annexin V/propidium iodide. Results. Radiation-induced apoptosis increased in order to radiation dose and data fitted to a semi logarithmic mathematical model. A positive correlation was found among radio-induced apoptosis values at different radiation doses: 1, 2 and 8 Gy (p < 0.0001 in all cases). Mean DSB/Gy/DNA unit obtained was 1.70 ± 0.83 (range 0.63-4.08; median, 1.46). A statistically significant inverse correlation was found between initial damage to DNA and radio-induced apoptosis at 1 Gy (p = 0.034). A trend toward 2 Gy (p = 0.057) and 8 Gy (p = 0.067) was observed after 24 hours of incubation. Conclusions. An inverse association was observed for the first time between these variables, both considered as predictive factors to radiation toxicity.

Role of the paclitaxel-eluting stent and tirofiban in patients with ST-elevation myocardial infarction undergoing postfibrinolysis angioplasty: the GRACIA-3 randomized clinical trial.

BACKGROUND A catheter-based approach after fibrinolysis is recommended if fibrinolysis is likely to be successful in patients with acute ST-elevation myocardial infarction. We designed a 2x2 randomized, open-label, multicenter trial to evaluate the efficacy and safety of the paclitaxel-eluting stent and tirofiban administered after fibrinolysis but before catheterization to optimize the results of this reperfusion strategy. METHODS AND RESULTS We randomly assigned 436 patients with acute ST-elevation myocardial infarction to (1) bare-metal stent without tirofiban, (2) bare-metal stent with tirofiban, (3) paclitaxel-eluting stent without tirofiban, and (4) paclitaxel-eluting stent with tirofiban. All patients were initially treated with tenecteplase and enoxaparin. Tirofiban was started 120 minutes after tenecteplase in those patients randomly assigned to tirofiban. Cardiac catheterization was performed within the first 3 to 12 hours after inclusion, and stenting (randomized paclitaxel or bare stent) was applied to the culprit artery. The primary objectives were the rate of in-segment binary restenosis of paclitaxel-eluting stent compared with that of bare-metal stent and the effect of tirofiban on epicardial and myocardial flow before and after mechanical revascularization. At 12 months, in-segment binary restenosis was similar between paclitaxel-eluting stent and bare-metal stent (10.1% versus 11.3%; relative risk, 1.06; 95% confidence interval, 0.74 to 1.52; P=0.89). However, late lumen loss (0.04+/-0.055 mm versus 0.27+/-0.057 mm, P=0.003) was reduced in the paclitaxel-eluting stent group. No evidence was found of any association between the use of tirofiban and any improvement in the epicardial and myocardial perfusion. Major bleeding was observed in 6.1% of patients receiving tirofiban and in 2.7% of patients not receiving it (relative risk, 2.22; 95% confidence interval, 0.86 to 5.73; P=0.14). CONCLUSIONS This trial does not provide evidence to support the use of tirofiban after fibrinolysis to improve epicardial and myocardial perfusion. Compared with bare-metal stent, paclitaxel-eluting stent significantly reduced late loss but appeared not to reduce in-segment binary restenosis. CLINICAL TRIAL REGISTRATION URL: http://clinicaltrials.gov. Unique identifier: NCT00306228.

Construcción y validación del cuestionario G_Clinic para medir la satisfacción laboral en profesionales de enfermería de las unidades de gestión clínica.

BACKGROUND Job satisfaction of nurses is a determinant factor in the quality and organizational adaptation of clinical management models in the current socio-economic context. The aim of this study was to construct and validate a questionnaire to measure job satisfaction of nurses in the Clinical Management Units in the Andalusian Public Health System. METHODS Clinimetric and cross-sectional study with a sample of 314 nurses of two university hospitals from Seville. Nurses were surveyed in 2011, from March to June. We used the Font Roja questionnaire adapted to our study variables. We performed analyses of correlations, reliability and construct validity, using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) to test the a priori model. RESULTS The end questionnaire consists of 10 items, whose internal consistency was 0.75, with a percentage of variance explaining of 63.67%. CFA confirmed 4 dimensions (work environment, work relationships, motivation, and recognition): significant χ2 (p < .001); χ2/gl = 2.013; GFI= 0.958, RMR = 0.055 y RMSEA = 0.057; AGFI = 0.927, NFI = 0.878, TLI = 0.902, CFI =0.933 e IFI = 0.935; AIC = 132.486 y ECVI = 0.423. CONCLUSION This new questionnaire (G_Clinic) improves clinimetric values of the Font Roja questionnaire, because it reduces the number of items, improves the reliability of the dimensions, increases the value of variance explained, and allows knowing job satisfaction of nurses in clinical managementt.