Antibody against tubulin from porcine brain was used to examine the distribution of tubulin in developing spermatids of Polytrichum and mature spermatozoids of Sphagnum. Cells were prepared for indirect immunofluorescence microscopy after fixation in buffered paraformaldehyde and brief incubation in cellulase. Pretreatment with cold methanol resulted in considerably enhanced immunofluorescence ...

the pollution of aquatic ecosystems may affect natural reproduction of fish populations by decreasing the fertilization efficiency. among the various sources of pollution, heavy metals are important group, being found in both freshwater and marine environment. the present study investigated changes of sperm characteristics of caspimyzon wagneri when exposed to manganese (mn). spermatozoids were...

Johannes Vermeer and Anthon van Leeuwenhoek are among the greatest geniuses in Art and Science respectively. During the seventeenth century, they achieved innovative advances. Vermeer, in painting, created a new intimate view of people specially women, developing the treatment of light and details. Leeuwenhoek, friend of Vermeer, influenced him in the use of the obscure camera in his works. In ...

This work evaluates the diet and the reproductive cycle of Tropidurus torquatus in relation to seasonality in a rock outcrop formations in a remaining area of Atlantic Rainforest. The data indicate that the lizards feed mainly on arthropods and plant material. The female reproductive activity varies between seasons, while males contain spermatozoids throughout the year. The minimum body size at...

One of the polyketide compounds, the naphthoquinone pigment echinochrome, is synthesized in sea urchin pigment cells. We analyzed polyketide synthase (pks) and sulfotransferase (sult) gene expression in embryos and larvae of the sea urchin Strongylocentrotus intermedius from various stages of development and in specific tissues of the adults. We observed the highest level of expression of the p...

NR5A1 is essential for the development and for the function of steroid producing glands of the reproductive system. Moreover, its misregulation is associated with endometriosis, which is the first cause of infertility in women. Hr39, the Drosophila ortholog of NR5A1, is expressed and required in the secretory cells of the spermatheca, the female exocrine gland that ensures fertility by secretin...