Biochemical and biological characterization of Bothriechis schlegelii snake venoms from Colombia and Costa Rica.

Snakebites inflicted by the arboreal viperid snake Bothriechis schlegelii in humans are characterized by pain, edema, and ecchymosis at the site of the bite, rarely with blisters, local necrosis, or defibrination. Herein, a comparative study of Bothriechis schlegelii snake venoms from Colombia (BsCo) and Costa Rica (BsCR) was carried out in order to compare their main activities and to verify the efficacy of Bothrops antivenom produced in Brazil to neutralize them. Biochemical (SDS-PAGE and zymography) and biological parameters (edematogenic, lethal, hemorrhagic, nociceptive, and phospholipase A2 activities) induced by BsCo and BsCR snake venoms were evaluated. The presence of antibodies in Bothrops antivenom that recognize BsCo and BsCR snake venoms by enzyme-linked immunosorbent assay and Western blotting, as well as the ability of this antivenom to neutralize the toxic activities were also verified. SDS-PAGE showed differences between venoms. Distinctive caseinolytic and hyaluronidase patterns were detected by zymography. BsCo and BsCR showed similar phospholipase A2 activity. Strong cross-reactivity between BsCo and BsCR was detected using Bothrops antivenom with many components located between 150 and 35 kDa. BsCR was more edematogenic and almost fourfold more hemorrhagic than BsCo, and both venoms induced nociception. BsCR (LD50 5.60 mg/kg) was more lethal to mice than BsCo (LD50 9.24 mg/kg). Bothrops antivenom was effective in the neutralization of lethal and hemorrhagic activities of BsCo and BsCR and was partially effective in the neutralization of edematogenic and nociceptive activities. In conclusion, geographic distribution influences the composition and activities of Bothriechis schlegelii venoms. Bothrops antivenom cross-reacted with these venoms and was partially effective in neutralizing some toxic activities of BsCo and BsCR.

Niveles séricos de alfa-fetoproteína en la población cubana. Valores normales y en neoplasias malignas de la infancia / Serum alpha-fetoprotein levels in the Cuban population. Normal values and values in the course of malignant neoplasms in infancy

Se estudiaron los niveles séricos de alfa-fetoproteina en 133 individuos normales de la población cubana, mediante una técnica de radioinmunoanálisis. Los valores normales mostraban tendencia a aumentar a medida que aumentaba la edad de los individuos estudiados. Al analizar sueros de niños con algunas enfermedades malignas, se encontraron concentraciones elevadas de alfa-fetoproteína en los sueros de algunos pacientes con retinoblastomas, tumores embrionarios y seminomas. En el estudio evolutivo de uno de los pacientes, se encontró buena correlación clínica con la variación de los niveles séricos de alfa-fetoproteína(AU)