Pristane-induced arthritis in mice selected for maximal or minimal acute inflammatory reaction.

The role of inflammatory and specific immune responses in pristane-induced arthritis (PIA) was investigated in mouse lines produced by bi-directional selective breedings for maximal (AIRmax) or minimal (AIRmin) acute inflammatory reaction, comparing the outcome of PIA and the humoral and cellular response to hsp65. Symptoms of arthritis were detected in 50 % AIRmax mice 120 days after pristane injection, reaching a maximal incidence of 65 %, whereas only 7 % of AIRmin mice developed arthritis within an observation period of 200 days. The production of IgG antibody against hsp65 was found to be similar on both lines, although the IgG1 isotype was predominant in AIRmax, and IgG2a in AIRmin line. In vitro T cell proliferation to hsp65 was similar in the two lines, however, ELISPOT assays carried out soon after pristane treatment, demonstrated higher numbers of IL-6-, TNF-alpha- and IL-4-secreting cells in the spleen of AIRmax than in AIRmin mice, while higher numbers of IFN-gamma-producing cells were found in AIRmin mice. These results suggest a major participation of acute inflammatory mechanisms in the susceptibility to PIA. The genetic background which determines high or low AIR favors a Th2-like response in susceptible AIRmax and Th1-like response in resistant AIRmin mice at the initial phase of arthritis induction.

The internal orbital facial breadth and middle facial breadth in Mongoloid crania from Peru and east Asia, with special reference to their significance as a racial criterion.

The internal orbital facial breadth (BIFMO), middle facial breadth (BIZM) and their dimensional relationship in 789 crania from 3 Peruvian and 7 East Asian series were examined to determine a Mongoloid criterion. The results confirmed that BIZM was invariably greater than BIFMO in the Peruvian and East Asian series, and clearly different from the quoted European and African populations (Ducros, 1965). Further discussion, which referred to world population data by Woo and Morant (1934), showed that the relationship between BIZM and BIFMO was useful as a simple racial criterion to distinguish the Mongoloid series, except in special cases such as the Oceanians.

Estudo histoquímico comparativo da matriz extracelular de tumores primários e metastáticos em ratos nude xenotransplantados com células KB / Histochemical comparative study of primary and metastatic tumors in nude rates xenotransplanted with KB cells

Estudou-se comparativamente, através de métodos histoquímicos, a expressäo dos componentes da matriz extracelular de tumores primitivos e metastáticos em ratos nude, xenotransplantados com células KB. Em ambas as neoplasias observou-se uma variabilidade tanto qualitativa como quantitativa dos componentes matriciais, coexistência de diferentes tipos de fibras, pouca representatividade de fibras elásticas de glicosaminoglicanas ácidas e sulfatadas e de polissacarídeos neutros, além da ausência de membrana basal

Occurrence of tetrodotoxin and paralytic shellfish toxins in Phallusia nigra (Tunicata, Ascidiacea) from the brazilian coast

We have already shown the presence of guanidine neurotoxins in calcareous red algae and mussels collected in the Säo Sebastiäo channel State of Säo Paulo,Brazil). It is known that these neurotoxins comprise more than 25 analogues such as tetrodotoxin (TTX) and derivatives plus the paralytic shellfish toxins (PST) found in a variety of marine, freshwater and amphibious species. Filter feeding animals generally possess large amounts of these neurotoxins. The tunicates are sessil marine animals with a high rate of sea water filtration. The tunics and siphons of 50 specimens of Phallusia nigra were dissected and the visceral organs were immersed in methanol containing acetic acid 0.02 N ph 5.0. The extract was prepared by homogenization, filtration and the methanolic phase was concentrated under reduced pressure and defatted with chloroform. The polar phase was evaporated and the residue dissolved in deionized water for further purification in ionic-exchange resin column (Bio-Gel P-2) and HPLC analysis. The extract showed paralytic effects on mouse assay (26.9 MU/100mg) and on crustacean isolated nerve preparations. The chemical analysis for TTX and PST revealed toxins with retention times similar to gonyautoxins, saxitoxins and TTX. These findings are important to explain future toxin envenoming outbreaks on the Brazilian coast.

Guanidine neurotoxins are released with the digestive fluid of crabs (Crustacea, Brachyura).

During agonistic interactions intertidal crabs, when exposed to air, produce a foam made of digestive secretions, sea water and air bubbles. They also may release their digestive secretions in water when disturbed. Crabs belonging to the families Majidae, Xanthidae and Portunidae from Atlantic and Pacific areas, not related with human poisoning, possess substances in their digestive secretion which are neurotoxic to mice, block action potentials in nerve preparations, and are reversible on washing. After purification in Bio-gel P-2 chromatography and HPLC analysis, the spontaneously regurgitated secretion, the digestive secretion collected by stomach cannulation of crabs, and the water aquarium replete of intertidal crabs kept overnight show the presence of guanidine neurotoxins.

Caquexia cancerosa em modelo experimental rato nude atímico/tumor humano KB / Cancerous cachexia in athymic nude rat experimental model/human tumor KB

1. Newborn anthymic nude rats, innoculated with KB human tumor, normally develop a great level of tumoral taken. With the augmentation in volume of the tumoral mass, animals may enter in a cachetic state that leads them to death. 2. However, proportionally to the total of days of observation, the number of rats that enter in cachexia was significantly greater than in the group that did not develop growth of tumoral mass post-innoculum. 3. This fact may suggest that any factor produced by the organism, in an excessive amount, with the aim to hinder the development of the tumoral mass, ha d a parallel effect strondgly cachetizing. 4. Relevant is the fact that the production of this substance may be thymus-independent, since these animals are congenitally athymic