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Biomedical subjects

M E Lefevre

Publications and source records attributed to M E Lefevre.

4 recordsLinked to original sources

Retention of ingested latex particles in Peyer's patches of germfree and conventional mice.

Conventional and germfree mice ingested a suspension of 2-micron latex particles in drinking water for a 15-day period. Number and distribution of intestinal Peyer's patches did not differ significantly in the two types of mice. Cleared Peyer's patches were compared with regard to size and particle content. The location of particles within Peyer's patch follicles of germfree mice was similar to that of conventional mice, but the latter had significantly larger follicles and greater accumulations of latex particles. Latex concentration varied with patch location. Proximal patches contained the majority of particles in germfree mice, whereas particles were most abundant in distal patches of conventional mice. The results show that particle uptake into Peyer's patches takes place even in the complete absence of bacteria in the gut.

Animals↗

Sex differences in Necturus urinary bladders.

We describe morphological sex differences in urinary bladders of the urodele amphibian Necturus maculosus. The mucosal epithelial cells of bladders from males were tall and contained considerable PAS-positive material. In scanning electron micrographs of the mucosal surface, epithelial cells from male bladders were well demarcated and were capped with microplicae or with long cilia. The mucosal epithelial cells of bladders from females were low and contained only a small amount of PAS-positive material; in scanning electron micrographs cell boundaries could not be distinguished and no cilia or microplicae were present. Bladders from males had higher transepithelial potential difference and lower water content than bladders from females. Urine analyses were not significantly different in the two sexes. It is suggested that response to androgens in the male accounts for the observed differences.

Animals↗