Browsing by Author "Gonzalez, F"

Now showing 1 - 4 of 4
  • Thumbnail Image
    Item
    Hemostatic disorder of uremia: The platelet defect, main determinant of the prolonged bleeding time, is correlated with indices of activation of coagulation and fibrinolysis
    (GEORG THIEME VERLAG KG, 1996) Mezzano, D; Tagle, R; Panes, O; Perez, M; Downey, P; Munoz, B; Aranda, E; Barja, P; Thambo, S; Gonzalez, F; Mezzano, S; Pereira, J
    Several parameters of primary hemostasis and markers of activation of coagulation and fibrinolysis were measured in 38 patients with severe (creatinine clearance <20 ml/min) chronic renal failure (CRF) without dialysis and diseases or drugs affecting hemostasis. Bleeding time (BT) was prolonged in 25/48 patients, and was correlated with age of patients, severity of renal failure, hematocrit, impairment in platelet aggregation-secretion and decrease in platelet ATP content. Defects in von Willebrand factor played no role in the prolongation of the BT. Multivariate analysis showed that only platelet dysfunction and severity of renal disease were independent predictors of the BT in uremia. The platelet functional disorder was significantly correlated with a reduction in platelet ATP and ADP.
  • Thumbnail Image
    Item
    Inflammation, not hyperhomocysteinemia, is related to oxidative stress and hemostatic and endothelial dysfunction in uremia
    (BLACKWELL SCIENCE INC, 2001) Mezzano, D; Pais, EO; Aranda, E; Panes, O; Downey, P; Ortiz, M; Tagle, R; Gonzalez, F; Quiroga, T; Caceres, MS; Leighton, F; Pereira, J
    Background. Several cardiovascular risk factors are present in patients with chronic renal failure (CRF), among which are systemic inflammation and hyperhomocysteinemia. Increased oxidative stress, endothelial activation/dysfunction, and coagulation activation are considered integral components of the inflammatory response, but have also been proposed as mediators of plasma homocysteine (tHcy)-induced cell damage. Using correlation analysis, we assessed the relative contributions of inflammation and hyperhomocysteinemia in the abnormal oxidative stress, endothelial activation/dysfunction, and hemostasis activation in patients with CRF.
  • Thumbnail Image
    Item
    Sun exposure behaviors and knowledge among Chileans
    (SOC MEDICA SANTIAGO, 2005) Molgo, M; Castillo, C; Valdes, R; Romero, W; Jeanneret, V; Cevo, T; Torres, C; Silva, P; Flores, L; Riquelme, A; Ayala, MF; Gonzalez, F; Hasbun, MT; Baladron, MJ
    Background: Ultraviolet light exposure has a pathogenic effect on the development of skin cancer whose prevalence increases worldwide. In Chile and the rest of the world, preventive educational campaigns are carried out to change high risk sun exposure behaviors. Aim To study the behavior of the Chilean population towards skin cancer prevention and to identify erroneous preventive practices and concepts. Material and methods: A survey containing 17 questions about sun exposure behaviors, photoprotective measures and knowledge about ultraviolet radiation and skin cancer was used. It was applied during January and February 2004, to 1,143 subjects (mean age 30 years, 409 males), taking vacations in beach resorts in Chile. Results: The hours of higher sun, exposure ranged from 12 AM to 4 PM. Thirty seven percent of subjects were exposed more than 2 hours during this high risk lapse. Women and subjects aged less than 25 years were Those with the riskiest behaviors. Fifty four percent used some type of photoprotection and 50% used ocular protection. Seventy percent used creams with sun screen and 74% used a sun protection factor higher than 15. Seventy percent applied The sun screen as recommended. Thirty eight percent had at least one sun burn in the last two years. More than 90% of subjects were aware of the relationship between sun exposure and skin cancer but 60% did not know the hours of higher ultraviolet radiation. The information about sun exposure was obtained from television in 57% of surveyed individuals. Conclusions: More educational campaigns about the risk of sun exposure are needed to reduce risky behaviors in the Chilean population.
  • Thumbnail Image
    Item
    Tranexamic acid inhibits fibrinolysis, shortens the bleeding time and improves platelet function in patients with chronic renal failure
    (F K SCHATTAUER VERLAG GMBH, 1999) Mezzano, D; Panes, O; Munoz, B; Pais, E; Tagle, R; Gonzalez, F; Mezzano, S; Barriga, F; Pereira, J
    Background: A defect in platelet function is the main determinant of the prolonged bleeding time in chronic renal failure (CRF). We previously reported a significant correlation between platelet abnormalities and elevated plasma markers of plasmin and thrombin generation. Our aim was to explore thr effect of inhibiting both plasmin action with tranexamic acid (TA) and thrombin production with low molecular weight heparin (LMWH), on the bleeding time (BT) and platelet function in patients with CRF. Methods: 37 patients with CRF (mean creatinine 8.6 +/- 4.4 mg/dl) under conservative treatment, with prolonged BT, entered this study and received TA during 6 days, with (n = 24) and without LMWH (n = 13). BT, platelet aggregation/secretion, platelet granule contents, von Willebrand factor and parameters of coagulation and fibrinolysis were recorded before and at the end of treatment. Results: The BT was shortened in 26/37 (67%) patients. This effect was associated with significant improvement of platelet aggregation and secretion, with decrease to a normal range of fibrin/fibrinogen degradation products, mild increase in plasmin-antiplasmin complexes and pronounced reduction of circulating plasminogen. No differences were seen among patients with or without LMWH. No serious side effects or complications were observed. Interpretation: These findings indicate that the activation of fibrinolysis plays a significant role in the defect of primary hemostasis in patients with CRF. inhibition of plasmin activity with TA shortens the BT and improves platelet function in the majority of patients with severe disease.