CNP mediated selective toxicity on melanoma cells is accompanied by mitochondrial dysfunction.

Cerium (Ce) oxide nanoparticles (CNP; nanoceria) are reported to have cytotoxic effects on certain cancerous cell lines, while at the same concentration they show no cytotoxicity on normal (healthy) cells. Redox-active CNP exhibit both selective prooxidative as well as antioxidative properties. The former is proposed to be responsible for impairment of tumor growth and invasion and the latter for rescuing normal cells from reactive oxygen species (ROS)-induced damage. Here we address possible underlying mechanisms of prooxidative effects of CNP in a metastatic human melanoma cell line. Malignant melanoma is the most aggressive form of skin cancer, and once it becomes metastatic the prognosis is very poor. We have shown earlier that CNP selectively kill A375 melanoma cells by increasing intracellular ROS levels, whose basic amount is significantly higher than in the normal (healthy) counterpart, the melanocytes. Here we show that CNP initiate a mitochondrial increase of ROS levels accompanied by an increase in mitochondrial thiol oxidation. Furthermore, we observed CNP-induced changes in mitochondrial bioenergetics, dynamics, and cristae morphology demonstrating mitochondrial dysfunction which finally led to tumor cell death. CNP-induced cell death is abolished by administration of PEG-conjugated catalase. Overall, we propose that cerium oxide nanoparticles mediate cell death via hydrogen peroxide production linked to mitochondrial dysfunction

El campo médico argentino y su mirada al tribadismo, 1936-1955 The medical argentine field and its look on the tribadism, 1936-1955

Este artículo describe y analiza la articulación discursiva sobre el lesbianismo en el campo médico argentino entre 1936 y 1955. Las "verdades" de la medicina poseen una fuerza normativa que constituyen un lugar privilegiado para propiciar la aplicación del modelo heterosexual e imponer esta visión al resto de la sociedad. En primer lugar esbozaremos los argumentos médicos en el ámbito europeo por ser los referentes más recorridos por la elite médica argentina. Luego, analizaremos las relecturas y apropiaciones realizadas en el contexto argentino articulándolas con el modelo hegemónico heterosexual de feminidad.<br>This article describes and analyzes the discursive articulation on the lesbianism in the medical Argentine field between 1936 and 1955. The "truths" of the medicine possess a normative force which constitutes a suitable place to favor the heterosexual model and to impose this point of view to the rest of the society. First we will outline the medical arguments in the European area. They were the most accessed models by the medical Argentine elite. Then, we will analyze the re-readings and appropriations realized in Argentina, articulating them with the hegemonic heterosexual model of femininity