Medicina
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beta-lapachone (beta-lap) is a lipophilic o-naphthoquinone isolated from the bark of the lapacho tree. Initial observations proved its capability for inhibiting growth of Yoshida tumor and Walker 256 carcinosarcoma. beta-Lap redox-cycling in the presence of reductants and oxygen yields "reactive oxygen species" (ROS: O2-, OH and H2O2) which cytotoxicity led to assume its role in beta-lap activity in cells. beta-Lap inhibited DNA synthesis in Trypanosoma cruzi as well as topoisomerases I and II, poly(ADP-ribose) polymerase (PARP) in different cells. These enzymes are essential for maintaining DNA structure. beta-Lap inhibited growth of a large variety of tumor cells including epidermoid laringeal cancer, prostate, colon, ovary and breast cancer and also different types of leukemia cells. ⋯ These enzymes activity, as well as ROS production by beta-lap redox-cycling, would be essential for beta-lap cytotoxicity. Diaphorase and NAD(P)H-quinone reductase, which catalyse beta-lap redox-cycling and ROS production, seem to play an essential role in beta-lap activity. On these grounds, clinical applications of beta-lap have been suggested.
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Multifocal motor neuropathy, a rare insidious immune-mediated disorder, features muscular weakness and atrophy, as well as areflexia, due to nerve conduction block and is often associated with the presence of anti-GM1 antibody. We report a patient with a nine-year history of progressive upper limb weakness, misdiagnosed as amyotrophic lateral sclerosis, who responded within hours to intravenous immunoglobulin treatment with full recovery of muscle strength. This case highlights the need to search for conduction block in patients with lower motor neuron involvement.
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In Argentina the first Hantavirus Pulmonary Syndrome (HPS) cases were characterized in 1995. Since then, Argentina is the country with the highest number of notified cases in South America. The disease is distributed in Northern, Southern and Central regions of the country, being Buenos Aires the most affected province from the Central region. ⋯ As. 60%. Andes virus lineages only cocirculated in La Plata city. These results will contribute to establish a risk map leading to the implementation of improved strategies of prevention.
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Adenocarcinomas (AC) account for more than 90% of the prostatic malignant neoplasias; a neuroendocrine differentiation (NE) component is to be considered in cases of atypical evolution for its diagnostic and therapeutic relevance. The (NE) originates by proliferation of the NE cells of the acinar epithelium and may develop into two different histologic patterns, a "Carcinoid" type and a "Small Cell" type. We report a patient with a prostatic AC diagnosed 5 years before his death with worsening of the disease together with a return of the prostatic specific antigen (PSA) to normal values and the presence of hepatic metastases of a tumor (NE) of the small cell type. The autopsy confirmed the presence of a prostatic tumor with areas of (AC) type and (NE) small cell type and multiple hepatic metastases (NE).
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Disseminated histoplasmosis is the most serious form of the disease produced by the fungus Histoplasma capsulatum. Histoplasmosis was first described by Darling in 1906, and it is endemic in certain areas of Central and Southeastern regions of USA, and most Latin America countries, including the Pampa húmeda and Mesopotamia regions in Argentina, but in other continents it has a limited regional distribution. ⋯ We report a case of disseminated histoplasmosis in a man with a myelodysplasia who presented a left tibial abscess, without any clinical evidence of pulmonary involvement. The patient was successfully treated with itraconazole.