The influence of lymphatic drainage on Calmette-Guérin bacillus (BCG)- induced granulomas was investigated by comparing the time course of granuloma formation in two sites: the hamster footpad and the check pouch, an area deprived of lymphatic vessels. Typical epithelioid granulomas developed in both sites. Whereas in the footpad the size of granulomas increased and the volume of the lesion persisted, in the pouch the lesion decreased in volume. The inoculation of BCG into the footpad of animal with granulomas in the pouch, reactivated the pouch lesions. T lymphocytes were detected by an immunocytochemical technique at the edge of these lesions. Inoculation of the bacteria into the pouch induces suppressive mechanisms which hold down the volume of the lesions induced in the footpad. The cutaneous purified protein derivative (PPD) test, positive in animals inoculated in the footpad, was always negative in animals with granulomas in the pouch. The number of bacteria per microscopic field in pouch granulomas increased from 10 to 1,000 after PPD injection. Evidence that PPD has a direct effect on pouch granuloma cells is given.
VARIATION OF WEIGHT AND SURVIVAL RATES OF MICRURUS CORALLINUS UNDER DIFFERENT FEEDING CONDITIONS IN LABORATORY ANIMAL ROOMS (SERPENTES, ELAPIDAE). The weight variation in Micrurus corallinus (Merrem, 1820) during the first 60 days in laboratory animal rooms was very remarkable. This fact demonstrates the difficulty in adaptation of these animals to the captive environment. The weight loss was observed in animals under voluntary feeding as well as forced feeding. The survival rate was significantly higher in voluntarily fed animals. Sex differences were also observed with higher survival rates for males. Low survival rates were observed in both sexes under forced feeding.
Since some colubrids can cause human envenomation, the importance of studies relating biological mechanisms to their venom apparatus is crucial. The present work dealt with morphological and histochemical characteristics of Duvernoy's gland of six opisthoglyphous colubrid species. The Duvernoy's gland of most species presented characteristics of a seromucous gland, except that of Oxyrhopus guibei, which did not show positive reaction to proteins indicating a mucoserous feature. We found variation in the quantity of serous cells among the species. This variation may be related to the presence of substances rich in carbohydrate-protein complex, and consequently to the toxic function of the secretion.
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