Prognostic factors in MNU and DMBA-induced mammary tumors in female rats.

Chemically-induced mammary tumors in rats by the carcinogens 1-methyl-1-nitrosourea- (MNU) and 7,12-dimethylbenz[a]anthracene (DMBA) are the most widely used models for studies related with human breast cancer. This study aimed to evaluate the immunoexpression of the prognostic factors estrogen receptor α (ERα), progesterone receptor (PR) and Ki-67, in MNU and DMBA-induced rat mammary tumors, in order to know the model that best suits to woman breast cancer. Twenty-eight MNU-induced and 16 DMBA-induced mammary tumors in virgin female Sprague-Dawley rats were analyzed.

Improving discrimination in the grading of rat mammary tumors using two-dimensional mapping of histopathological observations.

This work aims at characterizing rat mammary tumors induced by 7,12-dimethylbenz(a)anthracene (DMBA) and the respective malignancy potential, commonly graded with histopathology features grouped by intensity levels. Tumors were described over fourteen multiple ranged microscopic parameters and a comprehensive characterization of the histological patterns and their relation with tumor grade was carried out by principal component analysis (PCA). The number of histological patterns present on a tumor tends to correlate with malignant features.

Hepatic and renal toxicities of indomethacin acid, salt form and complexed forms with hydroxypropyl-β-cyclodextrin on Wistar rats after oral administration.

Indomethacin (IM), a non-steroidal anti-inflammatory drug, has the capacity to induce hepatic and renal injuries when administrated systemically. The aim of this study is to assess the IM absorption from complexed forms when orally administered to rats, by means of a comparative evaluation of its capacity to induce hepatic and renal injury in different forms, namely IM acid, IM sodium salt or IM complexed with hydroxypropyl-β-cyclodextrin (HP-β-CD), using freeze- and spray-drying methods. A total of 135 Wistar rats weighing 224.

Oral therapeutic vaccination with Streptococcus sobrinus recombinant enolase confers protection against dental caries in rats.

Dental caries is among the more prevalent chronic human infections for which an effective human vaccine has not yet been achieved. Enolase from Streptococcus sobrinus has been identified as an immunomodulatory protein. In the present study, we used S.

Immobilisation of cardosin A in chitosan sponges as a novel implant for drug delivery.

Cardosin A is extracted from the pistils of the plant Cynara cardunculus L. and chitosan is a polysaccharide derived from chitin with valuable properties as a biomaterial. In this work we report our experiments on the synthesis of chitosan sponges and immobilisation of cardosin A, by entrapment.

The characterisation of the collagenolytic activity of cardosin a demonstrates its potential application for extracellular matrix degradative processes.

Type I collagen is the major fibrous protein of mammals being needed to strengthen and organise the extracellular matrix (ECM). Connective tissue components are modulated by matrix metalloproteinases, which are critical for disintegration and remodelling of ECM under physiological and pathological conditions. Cardosin A is an abundant aspartic proteinase (AP) from Cynara cardunculus L.

Biocatalytic synthesis of highly ordered degradable dextran-based hydrogels.

We have prepared unique macroporous and ordered dextran-based hydrogels using a single-step biocatalytic transesterification reaction between dextran and divinyladipate in neat dimethylsulfoxide. These hydrogels show a unimodal distribution of interconnected pores with average diameters from 0.4 to 2.

Biocompatibility of chemoenzymatically derived dextran-acrylate hydrogels.

The biocompatibility of chemoenzymatically generated dextran-acrylate hydrogels has been evaluated in vitro, using human foreskin fibroblasts, and in vivo, by subcutaneous and intramuscular implantation in Wistar rats for up to 40 days. In vitro tests show that hydrogel extracts only minimally reduced (<10%) the mitochondrial metabolic activity of fibroblasts. Direct contact of the hydrogels with cells induced a cellular proliferation inhibition index (CPII) of 50-80%, compared with a control, whereas through indirect contact, the CPII values were <16%, suggesting that the high CPII values achieved in the direct assay test were likely due to mechanical stress or limitations in oxygen diffusion.