ABSTRACT
Paraneoplastic laboratory abnormalities are identified in several types of cancers in dogs and cats. In veterinary medicine, particularly in mammary cancer, there are few studies that correlate abnormal laboratory findings with tumor type and staging. The aim of this study was to evaluate hematological, biochemical, and hemostatic abnormalities and correlate them with mammary tumor staging in female dogs with mammary cancer. Blood samples from 24 female dogs were evaluated, and the hematological, biochemical, and hemostatic parameters were correlated with tumor staging obtained by physical examination, imaging exams, and histopathological surgical biopsies. The groups were organized according to tumor staging: group 1 (stages I and II), group 2 (stage III), and group 3 (stages IV and V). Anemia, neutrophilic leukocytosis, monocytosis, eosinophilia, thrombocytosis, hypoalbuminemia, hypocalcemia, hypoglycemia, and low blood urea were observed. The variables MCHC, TPP, and RDW were correlated with tumor staging with no clinical relevance. Thrombin time and fibrinogen were significant between the groups in the coagulation test, being associated with tumor staging. The findings suggest influence of the proinflammatory cytokines released during tumor growth.(AU)
Alterações laboratoriais de origem paraneoplásica são identificadas em diversos tipos de câncer de cães e gatos. Na medicina veterinária, existem poucos estudos que correlacionam os achados laboratoriais anormais com o tipo e estadiamento tumorais, principalmente em cadelas com neoplasia mamária. O objetivo deste estudo foi avaliar as alterações hematológicas, bioquímicas e hemostáticas em cadelas com neoplasia mamária e relacioná-las com o estadiamento tumoral. Foram coletadas amostras de sangue de 24 fêmeas caninas, e os parâmetros hematológicos, bioquímicos e hemostáticos obtidos foram relacionados com o estadiamento tumoral, realizado através do exame físico, exames de imagem e avaliação histopatológica após remoção cirúrgica. Os grupos foram organizados de acordo com o estadiamento tumoral em: Grupo 1 (estádios I e II), grupo 2 (estádio III) e grupo 3 (estádios IV e V). Observou-se anemia, leucocitose neutrofílica, monocitose, eosinofilia, trombocitose, hipoalbuminemia, hipocalcemia, hipoglicemia e diminuição de ureia sanguínea. As variáveis CHCM, PPT e RDW foram relacionadas com o estadiamento tumoral, porém sem relevância clínica. Nos testes de coagulação, o TT e o fibrinogênio apresentaram diferença significativa entre os grupos, sendo associado com estadiamento tumoral. Os resultados sugerem influência das citocinas pró-inflamatórias liberadas durante o crescimento do tumor.(AU)
Subject(s)
Animals , Female , Dogs , Paraneoplastic Syndromes/veterinary , Fibrinogens, Abnormal/analysis , Mammary Neoplasms, Animal/blood , Neoplasm Staging/veterinary , Clinical Laboratory Techniques/veterinaryABSTRACT
Con el propósito de estudiar el efecto de la vitamina E sobre el estrés oxidativo desencade- nado por hiperfibrinogenemia (HF) en un modelo experimental de aterogénesis y la posible normalización de los indicadores de estrés oxidativo, se evaluaron: óxido nítrico (NO), L-citrulina, superóxido dismutasa (SOD) e involución de lesiones histopatológicas en la aorta torácica. El estudio se realizó en 36 ratas, cepa Wistar, que se dividieron en tres grupos (n = 12 cada uno): A, control; B, HF × 90 días; C, HF × 90 días + vitamina E. La HF se indujo mediante inyecciones de adrenalina (0,1 ml/día/rata) por 90 días. La dosis de vitamina E fue de 2 mg/día/rata durante 75 días. Se dosaron en plasma los niveles de fibrinógeno (mg/dl), NO (uM) y L-citrulina (mM) y en lisado de glóbulos rojos, por espectrofotometría, se determinó la actividad de la SOD (U/ml). Se analizaron cortes de la aorta torácica por microscopia óptica (MO). Para el análisis estadístico se emplearon MANOVA y la prueba de Fisher; se estableció un nivel de significación de p < 0,05. Se observó un aumento significativo de fibrinógeno en el grupo B (407 ± 8,9 mg/dl) en comparación con los grupos A (203 ± 9 mg/dl) y C (191,58 ± 17,79 mg/dl) (p < 0,001). El NO disminuyó significativamente en el grupo B (13,73 ± 1,76 uM) frente a los grupos A (23,58 ± 0,08 uM) y C (26,64 ± 3,65 uM) (p < 0,001). La L-citrulina aumentó en forma significativa en los grupos B (4,99 ± 0,18 mM) y C (6,60 ± 0,16 mM) en comparación con el grupo A (3,03 ± 0,13 mM) (p < 0,001). El SOD incrementó su actividad en los grupos B (251,67 ± 10,34 U/ml) y C (304,75 ± 10,43 U/ml) frente al grupo A (139,44 ± 4,74 U/ml) (p < 0,001). La microscopia óptica mostró denudación endotelial, engrosamiento intimal y protrusión de la pared en el grupo B (90%) y recuperación de la denudación endotelial y disminución del 50% del engrosamiento intimal en el grupo C (p < 0,001). Niveles aumentados de SOD serían insuficientes para impedir alteraciones en la vía del estrés oxidativo inducido por la HF. La vitamina E actuaría deteniendo la reacción en cadena iniciada por los radicales libres y en consecuencia disminuiría el anión superóxido, estimulando de esta manera un incremento en la biodisponibilidad del NO y normalizando las concentraciones de fibrinógeno plasmático.
We used an experimental model of atherogenesis to evaluate the effect of vitamin E on oxidative stress induced by hyperfibrinogenemia (HF) and the possible normalization of oxidative stress markers. The following variables were studied: nitric oxide (NO), L-citrulline, superoxide dismutase (SOD) activity and regression of histopathological lesions in the thoracic aorta. The study was performed in 36 Wistar rats that were divided into three groups of 12 rats each: A, control group; B, HF for 90 days; C, HF for 90 days + vitamin E. Hyperfibrinogenemia was induced by the injection of epinephrine (0.1 ml/day/rat) during 90 days. The dose of vitamin E was 2 mg/day/rat during 75 days. We measured the plasma levels of fibrinogen (mg/dl), NO (uM) and L-citrulline (mM); SOD activity (U/ml) was assayed in red cell lysates using spectrophotometry. The histopathological sections of the thoracic aorta were examined using light microscopy (LM). Statistical analysis was performed using MANOVA and Fisher's test; a p value <0.05 was considered statistically significant. Rats in group B had a significant increase in fibrinogen levels B (407±8.9 mg/dl) compared to groups A (203±9 mg/dl) and C (191.58±17.79 mg/dl) (p<0.001). We observed a significant decrease in NO in group B (13.73±1.76 uM) versus groups A (23.58±0.08 uM) and C (26.64±3.65 uM) (p<0.001). L-citrulline increased significantly in groups B (4.99±0.18 mM) and C (6.60±0.16 mM) compared to group A (3.03±0.13 mM) (p<0.001). SOD activity was greater in groups B (251.67±10.34 U/ml) and C (304.75±10.43 U/ml) versus group A (139.44±4.74 U/ml) (p<0.001). Light microscopic examination revealed the presence of endothelial denudation, intimal thickening and vessel wall protrusion in group B (90%), while recovery of endothelial denudation and a 50% reduction in intimal thickening was observed in group C (p<0.001). High SOD activity might be insufficient to prevent abnormalities in the oxidative stress pathway induced by HF. Vitamin E would stop the chain reaction initiated by free radicals and thus decrease the superoxide anion, stimulating the bioavailability of NO with normalization of fibrinogen plasma levels.
ABSTRACT
Introducción: La hiperfibrinogenemia se considera predictora de eventos cardiovasculares en sujetos sanos y pacientes con cardiopatía isquémica. Como medida de prevención primaria, el bezafibrato disminuye el fibrinógeno sanguíneo y los eventos cardiovasculares, pero su efecto en el síndrome coronario agudo aún no se conoce. Material y métodos: Ensayo clínico, aleatorizado, controlado con tratamiento convencional. Se incluyeron pacientes con infarto agudo del miocardio con elevación del segmento ST y concentraciones de fibrinógeno > 500 mg/dl a las 72 horas de evolución. Se asignaron a recibir 400 mg de bezafibrato (grupo I) o tratamiento convencional (grupo II). Punto primario de evaluación: concentraciones de fibrinógeno; puntos secundarios: recurrencia de angina o infarto, falla ventricular izquierda y puntos finales combinados durante la estancia hospitalaria. Resultados: Se incluyeron 25 pacientes por grupo. Las concentraciones de fibrinógeno al egreso hospitalario fueron significativamente menores en el grupo I (532.42 ± 129.6 versus 889 ± 127.32 mg/dl del grupo II, p < 0.0001). Los puntos secundarios se presentaron con mayor frecuencia en el grupo II que en el grupo I: angina (56 versus 4%, riesgo relativo 0.071 [0.010-0.503], p < 0.0001), falla ventricular (24 versus 4%, riesgo relativo 0.167 [0.022-1.286], p = 0.049) y puntos finales combinados (76 versus 8%, riesgo relativo 0.105 [0.027- 0.405], p < 0.001). Conclusiones: El tratamiento con bezafibrato fue seguro y logró reducir el fibrinógeno en pacientes con infarto agudo. Esta reducción se asoció con menor frecuencia de eventos cardiovasculares a corto plazo.
BACKGROUND: Hyperfibrinogenemia is a predictor of cardiovascular events in healthy subjects and in patients with chronic ischemic heart disease. Bezafibrate decreases fibrinogen levels and also the incidence of major cardiovascular events in primary prevention, but its effects in acute coronary syndrome are unknown. METHODS: This is a randomized, controlled clinical trial with conventional therapy. We included patients with Acute ST Elevation Myocardial Infarction (STEAMI) and fibrinogen concentration >500 mg/dl at 72 h of evolution. We randomized subjects into two groups: bezafibrate 400 mg (group I) and conventional therapy (group II). Primary end point was decrease of fibrinogen concentrations. Secondary end points were recurrence of angina or infarction, left ventricular failure and combined end points during hospitalization. RESULTS: We included 25 patients in each group. Fibrinogen concentrations were lower at hospital discharge in Group I than in Group II (532.42 +/- 129.6 vs. 889 +/- 127.32 mg/dl in group II, p <0.0001). Secondary end points were more frequent in Group II than in Group I: angina (56% vs. 4%, RR 0.071 [0.010-0.503], p <0.0001), left ventricular failure (24% vs. 4%, RR 0.167 [0.022-1.286], p = 0.049) and combined end points (76% vs. 8%, RR 0.105 [0.027-0.405], p <0.001). CONCLUSIONS: Bezafibrate treatment was a safe treatment and reduced fibrinogen levels in patients with STEAMI and hyperfibrinogenemia. In the short term, this reduction was associated with a lower incidence of major cardiovascular events.