A divergent ADP/ATP carrier in the hydrogenosomes of Trichomonas gallinae argues for an independent origin of these organelles.

The evolution of mitochondrial ADP and ATP exchanging proteins (AACs) highlights a key event in the evolution of the eukaryotic cell, as ATP exporting carriers were indispensable in establishing the role of mitochondria as ATP-generating cellular organelles. Hydrogenosomes, i.e. ATP- and hydrogen-generating organelles of certain anaerobic unicellular eukaryotes, are believed to have evolved from the same ancestral endosymbiont that gave rise to present day mitochondria. Notably, the hydrogenosomes of the parasitic anaerobic flagellate Trichomonas seemed to be deficient in mitochondrial-type AACs. Instead, HMP 31, a different member of the mitochondrial carrier family (MCF) with a hitherto unknown function, is abundant in the hydrogenosomal membranes of Trichomonas vaginalis. Here we show that the homologous HMP 31 of closely related Trichomonas gallinae specifically transports ADP and ATP with high efficiency, as do genuine mitochondrial AACs. However, phylogenetic analysis and its resistance against bongkrekic acid (BKA, an efficient inhibitor of mitochondrial-type AACs) identify HMP 31 as a member of the mitochondrial carrier family that is distinct from all mitochondrial and hydrogenosomal AACs studied so far. Thus, our data support the hypothesis that the various hydrogenosomes evolved repeatedly and independently.

Special organelles of some pathogenic protozoa.

Parasitic protozoa comprise a large number of species, some of which are agents of important diseases. They are also of interest from the point of view of cell biology since they contain special organelles and structures. This review analyses our present knowledge of (1). the glycosomes, found in members of the Kinetoplastida order, (2). the hydrogenosomes found in some anaerobic protozoa, especially in trichomonads, (3). the acidocalcisomes, recently described in several protozoa, and (4). structures and organelles participating in the endocytic pathway in trypanosomatids.

Strategies by which some pathogenic trichomonads integrate diverse signals in the decision-making process.

The interaction between each one of Trichomonas vaginalis and Tritrichomonas foetus with their hosts is a complex process in which components associated to the cell surfaces of both parasites and host epithelial cells, and also to soluble components found in vaginal/urethral secretions, are involved. Either cytoadhesion or the cytotoxicity exerted by parasites to host cells can be dictated by virulence factors such as adhesins, cysteine proteinases, laminin-binding proteins, integrins, integrin-like molecules, a cell detachment factor, a pore-forming protein, and glycosidases among others. How trichomonads manipulate informations from the extracellular medium, transduce such informations, and respond to them by stimulating the activities of some surface molecules and/or releasing enzymes are the aspects concerning trichomonal virulence which are here briefly reviewed and discussed.

Strategies by which some pathogenic trichomonads integrate diverse signals in the decision-marking process

The interaction between each one of Trichomonas vaginalis and Tritrichomonas foetus with their hosts is a complex process in which components associated to the cell surfaces of both parasites and host epithelial cells, and also to soluble components found in vaginal/urethral secretions, are involved. Either cytoadhesion or the cytotoxicity exerted by parasites to host cells can be dictated by virulence factors such as adhesins, cysteine proteinases, laminin-binding proteins, integrins, integrin-like molecules, a cell detachment factor, a pore-forming protein, and glycosidases among others. How trichomonads manipulate informations from the extracellular medium, transduce such informations, and respond to them by stimulating the activities of some surface molecules and/or releasing enzymes are the aspects concerning trichomonal virulence which are here briefly reviewed and discussed.

Similes and metaphors I: A nature walk through benign gynecologic cytology.

Similes and metaphors useful in benign gynecologic cytology are presented. Included are those pertaining to normal cellular elements, organisms, contaminants, and benign changes.

Cell-associated and extracellular proteolytic activity of an oral flagellate, Trichomonas tenax.

Proteolytic activities in crude extracts and culture filtrates from Trichomonas tenax were determined using hide powder azure as substrate and the proteinase profiles in both samples were analysed in SDS-polyacrylamide gels containing copolymerized gelatin. The enzyme activity in the crude extract was detected over a broad pH range and was strongly activated by dithiothreitol, mainly in the pH range 5-8, and inhibited by cysteine proteinase inhibitors. Extracellular enzyme activity in culture filtrates was SH-dependent and increased continuously during incubation of the cell suspension, suggesting proteinase release. A total of seven distinct proteolytic bands could be detected in crude preparations. Three of these, with apparent Mr values 35,000, 45,000 and 56,000 and a pH optimum of 4-7, were SH-dependent and their inhibitory sensitivities were characteristic for cysteine proteinases. The 45,000 and 56,000 proteinases probably corresponded to those found in the culture filtrates. Proteolytic bands with apparent Mr 76,000, 87,000, 102,000 and 270,000 and pH optima in the alkaline region, pH 8-9, were independent of SH groups and were inhibited by a chelating agent EDTA, suggesting that they belong to the metalloproteinase family.

Pesquisa de Ureaplasma urealyticum pregnant women and the correlation with the presence of Trichomonas sp / Research of Ureaplasma urealyticum pregnant women and the correlation with the presence of Trichomonas sp

Foram feitas pesquisas de Ureaplasma urealyticum em material cervical e de Trichomonas sp no conteúdo vaginal de 74 gestantes. A existência ou näo de relaçäo entre a presença simultânea de Ureaplasma urealyticum e Trichomonas sp foi analisada, uma vez que os dados fornecidos pela literatura internacional säo bastante controvertidos. Trichomonas sp estava presente em 21,5% das amostras positivas para Urealyticum e em 13% das amostras em que a ausência do micoplasma foi constatada. Estatisticamente essas diferenças näo foram significantes impossibilitando inferir qualquer correlaçäo entre os dois achados

Pulmonary trichomoniasis and Trichomonas tenax.

Pulmonary trichomoniasis is usually caused by aspirated Trichomonas tenax. Adult men with chronic purulent or necrotic pulmonary disease are usually affected. Sixty-eight patients were previously described. A Russian study demonstrated pulmonary trichomoniasis in 19 of 112 patients (17%), mostly in patients with lung cancer, lung abscess, or bronchiectasis. Rarely, pulmonary trichomoniasis may be caused by an intra-abdominal (T. hominis) or genitourinary (T. vaginalis) infection. T. tenax is usually regarded as a harmless commensal of the human mouth. Its prevalence ranges from 4% to 53% and may exceed that of vaginal infection with T. vaginalis in adult females. It is frequently found in patients with poor oral hygiene. Cultural identification is superior to microscopic examination of wet-smear, gram-stained and Papanicolaou-stained preparations. Aspirated pulmonary trichomoniasis is an opportunistic infection. Until the question of possible pathogenicity is resolved, metronidazole should be given. The underlying pulmonary disease should be vigorously treated.

Immunohistochemical localization of fibronectin-like protein on the cell surface of the oral flagelatte Trichomonas tenax.

A protein immunologically related to fibronectin was demonstrated on the oral flagellate Trichomonas tenax. Two strains of T. tenax were used, the first freshly taken from ulcerative gingivitis and the second maintained in culture for 2 years. Initial investigations were made by established immunofluorescence staining procedures. Cells of the protozoa gave a positive fluorescence with anti-fibronectin anti-serum, while the controls were negative. Subsequently, indirect immunostaining procedures for electron microscopy were performed using the peroxidase procedure. Peroxidase deposits were detected on the outer layer of the cell membrane. Particularly intense labelling was localized in the contact areas between bacteria and protozoa, and sometimes within the marginal lamina of the undulating membrane. This fibronectin-like protein could potentially play an important role in the adhesion of Trichomonas tenax to gingival cells, connective tissue and in the phagocytosis of bacteria. The attachment of protozoa to gingival substrates could be the first step in the breakdown of periodontal tissues.

[Use of Dragan's high-speed PBT staining method in oral cytology examinations (author's transl)]. / Das PBT-Schnellfärbungsverfahren nach Dragan bei der Untersuchung der Mundzytologie.

Dragan's high-speed PBT (polychrome blue tannin) staining method enables cellular elements to be detected in oral smears in one minute at most. The basic dyes in the polychrome blue solution allow the acid-group-containing substrate to be detected in the nucleus, in the cytoplasm of epithelial cells and leukocytes, as well as in the elements of the flora. The chromatin shows a distinct basophilic, orthochromatic reaction. The fine, reddish-violet metachromatic granules in the cytoplasm are of a glycolipid nature and occur with the tonofibrils. The keratohyalin granules show a basophilic orthochromatic or metachromatic, homogeneous or granular reaction in relation to the chemically acid portions of their structure.

[Rodents trichomonads: morphology, life cycle and several ecologic features (Polymastigina)]. / Trikhomonady gryzunov: morfologiia, zhiznennyi tsikl i nekotorye osobennosti ekologii (Polymastigina)

Some morphological and cytochemical methods were applied to the study of the life cycle of Trichomonas parasitizing the intestine of various rodents. The comparative study of trophonts morphology showed that the only species of the genus Trichomonas--T. muris inhabits the intestine of mice, rats, field-voles, hamsters and susliks. The life cycle of T. muris includes three morphologically different stages: trophonts, pseudocysts and cysts. The pseudocysts and cysts are the infectious stages of T. muris. All rodents ingest them together with their food. The cysts of T. muris can survive for a long time (6 months and more) in the environment under the conditions of various temperature and humidity.