The effect of hormones on Trichomonas vaginalis

The hormonal milieu can alter susceptibility to infection. The effect of hormones on Trichomonas vaginalis was studied utilizing axenically cultured clinical isolates. Oestrogens, in physiological concentrations, decreased the growth of the organisms and their attachment to mammalian cells in vitro, and acted as a chemorepellent. The specificity of these effects was verified by their being blocked with anti-oestrogens, by the dose- and time-dependency of the responses, and by the lack of effect with other hormones. These results suggest that oestrogens may decrease the virulence of T. vaginalis; however, interactions between oestrogens and mammalian cells may promote the development of infection. Thus complicated interactions between hormones, micro-organisms and mammalian cells must determine whether exposure to oestrogens predisposes to or prevents the development of infection.

Ferredoxin-dependent reduction of nitroimidazole derivatives in drug-resistant and susceptible strains of Trichomonas vaginalis

The inhibitory effect of a range of nitroimidazole-derivatives on H2 production by metronidazole resistant (CDC-85) and susceptible (C1-NIH) Trichomonas vaginalis strains was investigated. The 2-, 4-, and 5-nitro-derivatives used had one-electron reduction potentials within the range -250 to -525 mV. Nitroimidazole concentrations giving 50% inhibition of H2 production (kiH2) for compounds with one-electron reduction potentials in the range -250 to -425 mV were found to be similar for both strains tested. Compounds with one-electron reduction potentials below -425 mV give 10-fold higher KiH2 values for the metronidazole resistant isolate. Both strains showed increased KiH2 for compounds with potentials lower than -500 mV. The addition of 2.1 kPa (0.02 atm) O2 to the gas phase resulted in increasing the kiH2 values for all the compounds tested, but had the greater effect on results obtained with the resistant isolate using nitroimidazoles in the range -425 to -490 mV. The results enable the proposal that the resistant isolate CDC-85 has a ferredoxin with altered redox properties or reduced intracellular levels.

An immunofluorescent study of the microtubule organization in Trichomonas vaginalis using antitubulin antibodies

The flagellated protozoon Trichomonas vaginalis, parasite of the human urogenital tract, possesses a well developed microtubule system organized in highly differentiated structures. We have shown by immunoblotting that monospecific anti-sheep brain tubulin antibodies are able to react with the microtubular tubulin of T. vaginalis. These antibodies were used to study the microtubular system of T. vaginalis both in interphase and mitosis by indirect immunofluorescence. The interphase microtubular pattern, characterized by an axostyle, a pelta, four anterior flagella, and a recurrent flagellum, displayed remarkable changes at the onset of mitosis: the axostyle disappeared, and two pole bodies connected by a short spindle became evident; chromosomal fibers arose while pole-to-pole fibers elongated. The last phases of mitosis were marked by the disappearance of chromosomal fibers, the appearance of two small axostyles, and the depolymerization of the pole-to-pole bundle. At the end of mitosis, the normal interphase microtubule pattern was observed.

[Significance of variations in the size of Trichomonas vaginalis in patients with dysplasia, intrapithelial and invasive planocellular carcinoma of the uterine cervix]

The study of the size of Trichomonas vaginalis in 100 patients with dysplasia and intraepithelial or invasive planocellular carcinoma of the uterine cervix and in 100 controls with trichomoniasis alone has shown that the parasites are of a significantly smaller diameter in carcinoma in situ (9.57 +/- 0.35 mu) and invasive carcinoma (10.44 +/- 0.66 mu) than in dysplasia (13.71 +/- 0.35 mu). The analysis of the variance has shown that this difference is statistically significant. In the control group with trichomoniasis alone, the diameter of Trichomonas vaginalis was twice as large (21.46 +/- 0.66 mu) as that in carcinoma and still larger than that in dysplasia. This indicates that small forms of Trichomonas vaginalis are more pathogenic than large ones and might be one of the causative agents of the atypical transformation of the squamous epithelium of the uterine cervix.

The size, density, and relative area of chromatic granules ("hydrogenosomes") in Trichomonas vaginalis Donne from cultures in logarithmic and stationary growth

Electron micrographs of Trichomonas vaginalis cells were examined morphometrically by means of an electronic image analyser. Cells from cultures in logarithmic growth contained smaller chromatic granules ("hydrogenosomes") and a higher proportion of sausage- or dumb-bell-shaped granules than did cells in stationary growth. These findings support the view that chromatic granules replicate by division of pre-existing granules and that this involves elongation and attenuation of their mid-region. The total area of cross sectioned granules occupied the same percentage of the cytoplasm of cells from cultures in logarithmic and stationary growth. The density of chromatic granules in the cytoplasm was identical for the two groups of cells.

Ultrastructural characteristics of Trichomonas vaginalis. An electron microscopical study

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