The effect of iron on metronidazole activity against Trichomonas vaginalis in vitro.

Metronidazole is administered in an inactive form then activated to its cytotoxic form within the hydrogenosome of trichomonads. Two hydrogenosomal proteins, pyruvate ferredoxin oxidoreductase (PFOR) and ferredoxin, play a critical role in the reductive activation of metronidazole. The expression of these proteins and other hydrogenosomal proteins are likewise positively regulated by iron. In the present study, the effect of iron on minimal lethal concentration (MLC) of metronidazole on in vitro cultured Trichomonas vaginalis(T. vaginalis) isolates was investigated. Interestingly, Addition of Ferrous ammonium sulphate (FAS) to T. vaginalis culture led to decrease in the MLC of metronidazole. On using aerobic assay, MLC of metronidazole on untreated T. vaginalis of both isolates was 12.5 µg/ml that decreased to 0.38 µg/ml on FAS treated trichomonads. Also anaerobic assay revealed that MLC on untreated parasites was 3.12 µg/ml that decreased to 0.097 µg/ml and 0.19 µg/ml for isolate 1 and isolate 2 respectively after iron addition. It was concluded that, addition of iron to in vitro cultured T. vaginalis decreases metronidazole MLC that was detected by both aerobic and anaerobic assays.

Effect of Nigella sativa alcoholic extract and oil, as well as Phaseolus vulgaris (kidney bean) lectin on the ultrastructure of Trichomonas vaginalis trophozoites.

Trichomonas vaginalis is a parasitic protozoan that is the aetiological agent of trichomoniasis, the most common non-viral sexually transmitted disease worldwide. Currently, the compound of choice for the treatment of T. vaginalis infections is metronidazole, however, it has many side effects and an increase in metronidazole-resistant trichomoniasis has been observed. Medicinal plants could be a source of new antiprotozoal drugs with high activity, low toxicity and lower price. The present work was carried out to investigate the therapeutic potential of Nigella sativa alcoholic extract and oil, as well as Phaseolus vulgaris (kidney bean) lectin and their in vitro activity on the ultrastructure of T. vaginalis trophozoites in comparison to metronidazole, as detected by transmission electron microscope. Both N. sativa oil and P. vulgaris lectin showed high toxic effect as evidenced by severe cell damage with cytoplasmic and nuclear destruction, while the effect of N. sativa alcoholic extract was moderate. Therefore, these two extracts could offer an effective, cheaper and more safe alternative for metronidazole in treatment of trichomoniasis.

Identification criteria of the rare multi-flagellate Lophomonas blattarum: comparison of different staining techniques.

Bronchopulmonary lophomoniasis (BPL) is an emerging disease of potential importance. BPL is presented by non-specific clinical picture and is usually accompanied by immunosuppression. Culture of Lophomonas blattarum is difficult and its molecular diagnosis has not yet been developed. Therefore, microscopic examination of respiratory samples, e.g., bronchoalveolar lavage (BAL) or sputum, is the mainstay of BPL diagnosis. Creola bodies and ciliocytophthoria are two forms of bronchial cells which occur in chest diseases with non-specific clinical picture like that of BPL. Both forms could be misrecognized as multi-flagellates because of their motile cilia in the wet mounts and due to shape variability of L. blattarum in stained smears. The aim of the study is to compare different staining techniques for visualizing L. blattarum to improve the recognition and diagnosis of BPL, to distinguish respiratory epithelial cells from L. blattarum and to decide which stain is recommended in suspected cases of BPL. BAL samples from patients which contain L. blattarum, creola bodies, and ciliocytophthoria were collected then wet mounts were examined. The BAL samples were also stained by Papanicolaou (PAP), Giemsa, hematoxylin and eosin (H & E), trichrome, Gram, and Diff-Quik (DQ) stains. The different staining techniques were compared regarding the stain quality. In wet mounts, the ciliary movement was coordinate and synchronous while the flagellar movement was wavy and leaded to active swimming of L. blattarum. In stained slides, bronchial cells were characterized by the presence of basal nucleus and the terminal bar from which the cilia arise. Trichrome was the best stain in demonstration of cellular details of L. blattarum. H & E, PAP, and Giemsa stains showed good quality of stains. Gram and DQ stains showed only pale hues of L. blattarum. We recommended adding Wheatley's trichrome staining to the differential diagnosis workup of cases of non-specific chest infections, especially when BPL is suspected, to avoid overdiagnosis or underdiagnosis of it.

Destructive effect of gamma irradiation on Echinococcus granulosus metacestodes.

Current options for treatment of cystic echinococcosis (CE), including chemotherapeutics and surgical approaches, are not satisfactory in certain cases of resistant cysts in vulnerable or inaccessible organs. Therefore, potential means of therapy are needed. The present work evaluated the effect of gamma irradiation on mestacestode causing CE. Metacestode of Echinococcus granulosus were exposed to 15, 30, and 60 Gy irradiation and examined after 24 h for viability, morphologic, and ultrastuctural alterations by light and electron microscopy. Apoptosis was determined by caspase-3 activity by colorimetric assay and immunohistochemistry. The irradiated metacestodes showed loss of viability, damage of protoscolices, formation of lipid droplets and vacuoles, and separation of the germinal layer. Apoptosis was prominent after irradiation. Our results suggested that gamma irradiation have therapeutic potential in CE. Moreover, understanding the destructive effect of irradiation may help in developing prophylactic measures against CE. Further studies are needed to test the efficacy of ionizing radiation in long-term animal models.