Contribution of mast cells and snake venom metalloproteinases to the hyperalgesia induced by Bothrops jararaca venom in rats.

Bothrops jararaca venom (Bjv) is known to induce local inflammation and severe pain. Since, mast cells are able to secrete mediators involved in algesic processes, in this study we examined the putative role of these cells in the hyperalgesia triggered by Bjv in the rat paw. We noted that treatment with mast cell stabilizer sodium cromoglicate as well as with histamine and 5-hydroxytriptamine receptor antagonists meclizine and methysergide, respectively, inhibited the Bjv-induced hyperalgesia.

Long-term exacerbation by interleukin 13 of IgE-mediated eosinophilia in rats.

Recent work shows that at least two cycles of antigen challenge applied in a 7-day interval are required to yield tissue eosinophil accumulation in IgE-passively sensitized rats. Since interleukin (IL)-13 is widely regarded as a key mediator in eosinophilic responses associated with mast cells and IgE, we investigated whether this cytokine could replace the first cycle of sensitization and challenge in its proeosinophilic role. We found that IL-13 (25 and 50 ng/cavity) injected into the rat pleural space led to eotaxin generation and a dose-dependent accumulation of eosinophils following IgE-passive sensitization and challenge 7 days later.

Meiothermus timidus sp. nov., a new slightly thermophilic yellow-pigmented species.

Several yellow-pigmented isolates, with optimum growth temperatures between 55 and 60 degrees C, were recovered from hot springs in Central Portugal and the Azores. Phylogenetic analysis of the 16S rDNA showed that these organisms represented a new species of the genus Meiothermus. The new isolates could be distinguished from other strains of the species of the genus Meiothermus by biochemical characteristics and the fatty acid composition because they had very high levels of iso C15:0 and iso C17:0 and very low levels of anteiso C17:0 and iso C16:0.

Germline MUTYH (MYH) mutations in Portuguese individuals with multiple colorectal adenomas.

Germinal mutations in the base excision repair (BER) gene MUTYH (MYH) have recently been described in association with predisposition to multiple colorectal adenomas and cancer. In contrast to the classic dominant condition of familial adenomatous polyposis (FAP) due to germinal mutations in the APC gene, the MYH polyposis is an autosomal recessive disease. The identification of individuals affected by MYH polyposis brings new and important implications for the diagnostic, screening, genetic counseling, follow up and therapeutic options in these patients.

Cyclin D1 A870G polymorphism and amplification in laryngeal squamous cell carcinoma: implications of tumor localization and tobacco exposure.

Altered Cyclin D1 activity, due to gene amplification and/or protein overexpression, is related to the development of several human cancers, including head and neck SCC. This study investigated the relationship between CCND1 A870G gene polymorphism and amplification with the development and progression of laryngeal SCC, considering the implications of tumor localization and tobacco exposure. The study population consisted of 66 larynx cancer patients and 110 healthy individuals.

A simple vascular calcification score predicts cardiovascular risk in haemodialysis patients.

Background: Cardiovascular morbidity and mortality are highly prevalent in haemodialysis (HD) patients and have been recently associated with vascular calcifications. The objective of our study was to assess the value of a simple vascular calcification score for the prediction of cardiovascular death, cardiovascular hospitalizations and fatal and non-fatal cardiovascular events in HD patients, and to correlate this score with cardiovascular disease and with other known predictors of vascular disease.

Methods: In this observational, prospective study 123 chronic HD patients (75 males and 48 females; 20% diabetic) were included, who were on low-flux HD treatment for 46.

[Digital morphometric and stereologic analysis of small intestinal mucosa in well-nourished and malnourished children with persistent diarrhea].

Objective: To test the hypothesis that the proximal small intestines of children with persistent diarrhea present morphometric and stereologic changes proportional to their nutritional status, using microscope images stored in a computer.

Methods: Cross-sectional study with 65 pediatric patients, whose ages ranged from 4 months to 5 years, with persistent diarrhea for over 14 days. The nutritional assessment was performed according to the z-scores for weight/age (W/A), weight/height (W/H) and height/age (H/A) ratios, divided into: well-nourished = z > or =2SD and malnourished = z<2SD; well-nourished = z > or =2SD, nutritional risk = z<1SD and malnourished = z<-2SD; and continuously, in descending order, using the NCHS charts.

Soluble factors released by Toxoplasma gondii-infected astrocytes down-modulate nitric oxide production by gamma interferon-activated microglia and prevent neuronal degeneration.

The maintenance of a benign chronic Toxoplasma gondii infection is mainly dependent on the persistent presence of gamma interferon (IFN-gamma) in the central nervous system (CNS). However, IFN-gamma-activated microglia are paradoxically involved in parasitism control and in tissue damage during a broad range of CNS pathologies. In this way, nitric oxide (NO), the main toxic metabolite produced by IFN-gamma-activated microglia, may cause neuronal injury during T.