The interaction of resveratrol with ferrylmyoglobin and peroxynitrite; protection against LDL oxidation.

Resveratrol (3,4',5-trihydroxystilbene) is a natural phytoalexin synthesized in response to injury or fungal attack, found in the grape skin and wine, specially red wine. A large number of studies have demonstrated that resveratrol regulates many biological activities, namely protection against atherosclerosis by a set of pharmacological properties, including the antioxidant activity. In this study, we explored the capacity of resveratrol in protecting low density lipoproteins (LDL) against either ferrylmyoglobin- or peroxynitrite-mediated oxidation and the underlying mechanisms of its antioxidant potential.

Proximal tubular basement membrane width in insulin-dependent diabetes mellitus.

Although glomerular structure has been studied, careful evaluation of tubular basement membrane (TBM) structure in diabetes in humans has not been done. We measured proximal TBM width, glomerular basement membrane (GBM) width, mesangial fractional volume [Vv(Mes/glom)], mesangial matrix fractional volume [Vv(MM/glom)], and cortical interstitial fractional volume [Vv(Int/cortex)] in 35 insulin-dependent diabetic (IDDM) patients and 20 controls. The patients' mean age was 28 +/- 10 years (X +/- SD) and IDDM duration was 17 +/- 8 years.

Modeling dissolution of sparingly soluble multisized powders.

The dissolution of powder drugs, besides being a topic of utmost importance, especially for the sparingly soluble ones, is far from being well-explained. The purpose of the present study is, on the one hand, to obtain experimental dissolution profiles and, on the other hand, to analyze and process the data for dissolution modeling. Three different size fractions of a widely used sparingly soluble drug--ibuprofen--were fully characterized with regard to its particle size distribution, specific surface area, density, solubility, and diffusion coefficient.

Thyroid function in post-weaning rats whose dams were fed a low-protein diet during suckling.

This study was designed to evaluate the thyroid and pituitary hormone levels in post-weaning rats whose dams were fed a low-protein diet during suckling (21 days). The dams and pups were divided into 2 groups: a control group fed a diet containing 22% protein that supplies the necessary amount of protein for the rat and is the usual content of protein in most commercial rat chow, and a diet group fed with a low-protein (8%) diet in which the protein was substituted by an isocaloric amount of starch. After weaning all dams and pups received the 22% protein diet.

Cytomorphology of a mixed pigmented/nonpigmented pleomorphic adenoma of the ciliary body: a diagnostic pitfall in the evaluation of intraocular tumors.

Intraoperative cytology is an alternative and sometimes preferred method to frozen section in the rapid evaluation of surgical biopsies. This report describes the cytological, histological, and immunohistochemical features of a case of mixed pigmented/nonpigmented pleomorphic adenoma of the ciliary body with clinical and morphological features reminiscent of malignant melanoma. The characteristic cyto-histomorphology of this unusual tumor and its distinguishing features from malignant melanoma are discussed.

Carcinosarcoma (malignant mixed müllerian (mesodermal) tumor) of the female genital tract: immunohistochemical and ultrastructural analysis of 28 cases.

In an attempt to clarify the histogenesis of carcinosarcoma (malignant mixed müllerian tumor) of the female genital tract, 20 uterine and eight ovarian tumors were studied by light microscopy, transmission electron microscopy, and immunohistochemistry. Cytokeratins (MAK-6 and AE1:AE3) and epithelial membrane antigen were detected in the epithelial component of all tumors and in the stromal component of 15 cases (55%). Vimentin was detected in the stromal component of all cases and was focally positive in the epithelial component of 18 cases (69%).

[Teaching-assistance integration: bases for a developmental proposal. Peru].

In formulating general policy guidelines for the health sector, it is theoretically necessary to redefine the place and the functions of institutional components, and to visualize the need and the possibility of an organized population as the principal subject of the teaching assistance process; giving thus reality to the concept of integration of teaching-service-community. The integration of teaching assistance is thus envisaged as a combined effort of the community, university and health services. It is a social process in the overall development of society.

[Health manpower in the Americas].

The article summarizes the country studies on the development of the health manpower situation published in this issue of Educación médica y Salud, Vol. 20, No. 3, 1986.

Role of granulocyte oxygen products in damage of Schistosoma mansoni eggs in vitro.

The objectives of this study were to describe the ultrastructure of granulocyte-Schistosoma mansoni egg interaction and to determine the role of reduced oxygen products as effectors of cell-mediated damage to the parasite target. Granulocytes attached to the parasites and closely applied their plasma membranes to the microspicules of the egg shell 30 min after mixing in the presence of immune serum. By 4 h, the egg shell was fractured and granulocyte pseudopodia extended toward the underlying miracidium.

Host granulomatous response in schistosomiasis mansoni. Antibody and cell-mediated damage of parasite eggs in vitro.

In chronic schistosomiasis mansoni the major pathologic lesions are granulomas surrounding eggs deposited in host tissues. Parasite ova release antigenic material that sensitize the host, resulting in the development of delayed-type hypersensitivity granulomas. The objectives of the present study were to assess the ability of components of the host granulomatous response to induce biochemical and biologic alterations in eggs in vitro, and to correlate these with the capacity of ova to induce granulomas in vivo.

Evolution of schistosomal hepatic vascular lesions after specific chemotherapy.

Mice infected with 30 cercariae of Schistosoma mansoni showed extensive destruction, obstruction, and distortion of the intrahepatic portal vein system 10 weeks after exposure. One month after curative treatment for schistosomiasis, these lesions had considerably regressed. The vascular pattern was almost normal by 2 months and completely normal by 6 months following treatment.

Enhanced helminthotoxic capacity of eosinophils from patients with eosinophilia.

To determine whether eosinophils from patients with eosinophilia have an enhanced capacity to kill parasites, we compared purified eosinophils (mean purity, 89 per cent) from 30 patients with various degrees of eosinophilia and with or without infection with Schistosoma mansoni for the capacity to kill schistosomula, the larval stage of S. mansoni, in vitro. There was a significant correlation between peripheral eosinophil count and antibody-dependent, eosinophil-mediated death of parasites after 40 hours of culture (P < 0.