A purified extract from prickly pear cactus (Opuntia fuliginosa) controls experimentally induced diabetes in rats.

The hypoglycemic activity of a purified extract from prickly pear cactus (Opuntia fuliginosa) was evaluated on STZ-induced diabetic rats. Blood glucose and glycated hemoglobin levels were reduced to normal values by a combined treatment of insulin and Opuntia extract. When insulin was withdrawn from the combined treatment, the prickly pear extract alone maintained normoglycemic state in the diabetic rats. The blood glucose response to administered glucose also showed that the rats receiving the combination treatment of insulin and Opuntia extract for 7 weeks followed by Opuntia extract alone were capable of rapidly returning blood glucose to the levels of the nondiabetic rats. Although the mechanism of action is unknown, the magnitude of the glucose control by the small amount of Opuntia extract required (1 mg/kg body weight per day) preclude a predominant role for dietary fiber. These very encouraging results for diabetes control by the purified extract of this Opuntia cactus make the need for clinical studies in humans evident.

Use of human skin to demonstrate antinuclear antibodies in lepromatous leprosy patients.

A common finding in the sera of leprosy patients is the presence of antinuclear antibodies (ANA), but their specificity for autologous antigens is unknown. The aim of this work was to investigate the reactivity of these ANA toward the cell nuclei of human skin. ANA were investigated in the sera of 35 patients with lepromatous leprosy by immunofluorescence reactions performed with sections of human skin biopsies (autologous from each patient and healthy human skin obtained from plastic surgery procedures), and compared with the results obtained when rat liver was used as substrate. ANA titer, immunofluorescence pattern, immunoglobulin classes (IgG and IgM) and complement-binding capability were also investigated. When human skin sections were used as substrates, 30 out of 35 patients (85.7%) gave positive ANA tests; most of them gave a 1:4 to 1:16 titer for IgG with an annular pattern and 1:4 for IgM with an annular or a granular pattern. ANA of 30 patients bound C1q and 14 bound C3. However, when rat liver sections were used as substrates only 9 out of 35 cases (27.1%) gave positive ANA tests. These results show that human skin sections are a better substrate to demonstrate the ANA present in the sera of patients with lepromatous leprosy. Their significance in the pathogenesis of tissue damage remains to be investigated.

Obtencion de antigeno Sm de celulas malignas del linfoma murino L5178Y. / Obtention of Sm antigen from L5178 murina lumphoma malignant cells

Tan y Kunkel demostraron en diversos tejidos humanos y animales un antigeno nuclear que denominaron Sm, el cual reacciona de manera especifica con aproximadamente 30 por ciento de los sueros de enfermos de lupus eritematoso generalizado. En el momento actual la fuente de obtencion de dicho antigeno para fines comerciales es el timo de conejo, del cual se prepara un extracto acetonico. En este estudio se demostro que las celulas del linfoma murino L5178Y, de origen timico, contienen dicho antigeno en abundancia el cual se extrae facilmente con solucion salina amortiguada cuando las celulas han recibido previamente un choque termico. Ademas de informarse por primera vez la presencia de dicho antigeno en un tejido neoplasico animal, se propone el metodo aqui empleado como fuente de obtencion del antigeno Sm, dado que su extraccion es facil, de bajo costo y de alto rendimiento