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Methylene blue reduction rates (MeBRR) were evaluated spectrophotometrically to study bovine spermatozoal mitochondrial function and its relation to motility. A chemical reaction (H2SO4, methylene blue solution, and zinc powder) was used to quantify methylene blue reduction. Absorbance measurements were made for 10 min at 609 nm in a narrow band spectrophotometer. In a second experiment, fresh ejaculates were assessed for concentration and motility evaluated with phase microscopy (37 degrees C). Semen was diluted to 100 million cells/mL in a sodium citrate-glucose buffer and methylene blue. Absorbance and motility were evaluated every 30 min for 2.5 h in a water-jacketed cuvette (41 degrees C). Methylene blue reduction rates and motility decreased at each subsequent period. Methylene blue reduction rates were correlated to sperm motility. Lastly, the methylene blue reduction rate was measured with a broad band spectrophotometer and compared with motility using similar conditions. Motility estimates were made on sperm from the cuvettes. Sperm motility was correlated to methylene blue reduction rates measured spectrophotometrically.

This paper defines vaginismus in depth, discusses therapeutic options with emphasis on the psycho-therapeutic approach in combination with behavioural therapy. Of 26 couples completing such treatment, 22 (85%) on completion were able to achieve full penetrative intercourse without discomfort and reported greater fulfillment in their sexual relationship. Although not all wanted to conceive, seven have since reported a pregnancy.

Human seminal plasma contains uniquely high concentrations of prostaglandins of the E series which are believed to contribute to its immunosuppressive effects in vivo. In order to obtain further insight into their activity we have compared the immunosuppressive properties in vitro of PGE1, PGE2 and 19-OH PGE using three immunological systems known to be modulated by prostaglandins, namely, mitogen induced lymphocyte proliferation, IL-2 and transferrin receptor expression and NK-cell mediated cytotoxicity. These studies revealed that PGE1 and PGE2 exerted a greater immunosuppressive effect than 19-OH PGE, but considerably higher levels of 19-OH PGE in semen might contribute the majority of immunosuppressive activity in vivo. Our studies also show that the lower stability of 19-OH PGE in culture media may be responsible for its lower immunosuppressive effect observed in vitro.

Considerable advances have been made in our understanding of cell growth regulation in mammalian cells. In particular, studies on transformed and normal cells have highlighted the contribution of growth factor-related control mechanisms in cell growth regulation. We set out to investigate whether host growth factors are involved in the growth regulation of the parasitic protozoan Trypanosoma brucei. We demonstrate that antibodies to the mammalian epidermal growth factor (EGF) receptor bind to the trypanosome T. brucei and, that these antibodies recognise a surface polypeptide of 135 kDa. This polypeptide is one of only two polypeptides in parasite extracts that bind EGF. Furthermore, EGF modifies protein kinase activity and growth rate of trypanosomes in vitro. These results lead to the conclusion that T. brucei has a surface growth factor receptor with considerable homology to the EGF receptor, and raise the possibility that growth factor interactions similar to those found in mammalian cells are involved in cell growth regulation in trypanosomes.