Establishment of suitable reference genes for studying relative gene expression during the transition from trophozoites to cyst-like stages and first evidences of stress-induced expression of meiotic genes in Trichomonas vaginalis

Trichomonas vaginalis is a parasite of the human urogenital tract and the causative agent of trichomoniasis, a sexually transmitted disease of worldwide importance. This parasite is usually found as a motile flagellated trophozoite. However, when subjected to stressful microenvironmental conditions, T. vaginalis trophozoites can differentiate into peculiar cyst-like stages, which exhibit notable physiological resistance to unfavourable conditions. Although well documented in morphological and proteomic terms, patterns of gene expression changes involved in the cellular differentiation into cyst-like stages are mostly unknown. The real-time reverse transcription polymerase chain reaction (RT-qPCR) is recognized as a sensitive and accurate method for quantification of gene expression, providing fluorescence-based data that are proportional to the amount of a target RNA. However, the reliability of relative expression studies depends on the validation of suitable reference genes, which RNAs exhibit a minimum of variation between tested conditions. Here, we attempt to determine suitable reference genes to be used as controls of invariant expression during cold-induced in vitro differentiation of T. vaginalis trophozoites into cyst-like forms. Furthermore, we reveal that the mRNA from the meiotic recombinase Dmc1 is upregulated during this process, indicating that cryptic sexual events may take place in cyst-like stages of T. vaginalis.

The Inhibitory Activity of Anthraquinones against Pathogenic Protozoa, Bacteria, and Fungi and the Relationship to Structure

Plant-derived anthraquinones were evaluated in cell assays for their inhibitory activities against the parasitic protozoa Trichomonas vaginalis human strain G3 that causes the sexually transmitted disease trichomoniasis in women, Tritrichomonas foetus bovine strain D1 that causes sexually transmitted diseases in farm animals (bulls, cows, and pigs), Tritrichomonas foetus-like strain C1 that causes diarrhea in domestic animals (cats and dogs), and bacteria and fungi. The anthraquinones assessed for their inhibitory activity were anthraquinone, aloe-emodin (1,8-dihydroxy-3-hydroxymethylanthraquinone), anthrarufin (1,5-dihydroxyanthraquinone), chrysazin (1,8-dihydroxyanthraquinone), emodin (1,3,8-trihydroxy-6-methylanthraquinone), purpurin (1,2,4-trihydroxyanthraquinone), and rhein (1,8-dihydroxy-3-carboxyanthraquinone). Their activities were determined in terms of IC₅₀ values, defined as the concentration that inhibits 50% of the cells under the test conditions and calculated from linear dose response plots for the parasitic protozoa, and zone of inhibition for bacteria and fungi, respectively. The results show that the different substituents on the anthraquinone ring seem to influence the relative potency. Analysis of the structure–activity relationships in protozoa indicates that the aloe-emodin and chrysazin with the highest biological activities merit further study for their potential to help treat the diseases in women and domestic and farm animals. Emodin also exhibited antifungal activity against Candida albicans. The suggested mechanism of action and the additional reported beneficial biological properties of anthraquinones suggest that they have the potential to ameliorate a broad spectrum of human diseases.

Performance of syndromic management for the detection and treatment of genital Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis among women attending antenatal, well woman and sexual health clinics in Papua New Guinea: a cross-sectional study

OBJECTIVE

Papua New Guinea (PNG) has among the highest estimated prevalences of genital Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) of any country in the Asia-Pacific region. Diagnosis and treatment of these infections have relied on the WHO-endorsed syndromic management strategy that uses clinical presentation without laboratory confirmation to make treatment decisions. We evaluated the performance of this strategy in clinical settings in PNG.

DESIGN

Women attending antenatal (ANC), well woman (WWC) and sexual health (SHC) clinics in four provinces were invited to participate, completed a face-to-face interview and clinical examination, and provided genital specimens for laboratory testing. We estimated the performance characteristics of syndromic diagnoses against combined laboratory diagnoses.

RESULTS

1764 women were enrolled (ANC=765; WWC=614; SHC=385). The prevalences of CT, NG and TV were highest among women attending ANC and SHC. Among antenatal women, syndromic diagnosis of sexually transmitted infection had low sensitivity (9%-21%) and positive predictive value (PPV) (7%-37%), but high specificity (76%-89%) and moderate negative predictive value (NPV) (55%-86%) for the combined endpoint of laboratory-confirmed CT, NG or TV. Among women attending WWC and SHC, 'vaginal discharge syndrome' had moderate to high sensitivity (72%-78%) and NPV (62%-94%), but low specificity (26%-33%) and PPV (8%-38%). 'Lower abdominal pain syndrome' had low sensitivity (26%-41%) and PPV (8%-23%) but moderate specificity (66%-68%) and high NPV (74%-93%) among women attending WWC, and moderate-high sensitivity (67%-79%) and NPV (62%-86%) but low specificity (26%-28%) and PPV (14%-33%) among SHC attendees.

CONCLUSION

The performance of syndromic management for the detection and treatment of genital chlamydia, gonorrhoea and trichomonas was poor among women in different clinical settings in PNG. New diagnostic strategies are needed to control these infections and to prevent their adverse health outcomes in PNG and other high-burden countries.

Prevalence of Selected Sexually Transmitted Infection (STI) and Associated Factors among Symptomatic Patients Attending Gondar Town Hospitals and Health Centers

BACKGROUND

Sexually transmitted infection (STI) is a major global cause of acute illness, infertility, long-term disability and death, with serious medical and psychological consequences to millions of men, women and infants. Moreover, in Ethiopia, epidemiological studies on STI among STI clinic clients are limited. Therefore, the aim of this study was to determine the prevalence and associated risk factors of sexually transmitted infection (STI).

METHODS

A cross sectional study was conducted between April and August 2014 among STI clinic clients in Gondar Town hospitals and health centers. One hundred twenty study participants who fulfill the criteria were included. Different laboratory methods and techniques were applied to identify the possible microorganisms. Data were entered and analyzed using SPSS version 20. Logistic regression was used to determine risk factors for STI and P values < 0.05 was considered statistically significant.

RESULTS

The overall laboratory test confirmed that STIs prevalence was 74.1% with 32.5% being Candida spp., 30% T. palladium, 20.8% N. gonorrhoeae and 14.2% T. vaginalis. Two or more organisms were isolated in 20% of the study subjects. Risk factors for STI had knowledge about STI and alcohol consumption.

CONCLUSION

The prevalence of N. gonorrhoeae, T. pallidum, T. vaginalis, and Candida spp. in the study area was high. It needs health education programs, promotes condom utilization and more comprehensive community based STI studies.

Demographic and behavioural risk factors associated with Trichomonas vaginalis among South African HIV-positive men with genital ulcer disease: a cross-sectional study

OBJECTIVES

Demographic and risky sexual behaviours may increase the risk for Trichomonas vaginalis (TV) infection and, thus, enhance HIV transmission to uninfected partners. We assessed the demographic and behavioural risk factors associated with TV among South African HIV-positive men with genital ulcer disease.

METHODS

We conducted a cross-sectional study with data from a randomised controlled trial conducted by the Centers for Disease Control and Prevention and the London School of Hygiene and Tropical Medicine. The data were obtained from three primary healthcare clinics in South Africa. At baseline (n=387), participants reported on demographics, sexual behaviour, history of sexually transmitted infections and clinical ulcers. The outcome TV was measured using real-time multiplex PCR assays and a Rotor-gene 3000 platform from the first and past urine samples of all participants. Logistic regression model estimated ORs and 95% CIs adjusted for demographics, sexual risk behaviours and ulcer conditions.

RESULTS

An estimated 11.4% of TV was detected among the men. The odds of TV infection were significantly associated with high blister counts (OR 4.0, 95% CI 1.6 to 28, p=0.01), ulcer pain (OR 0.4, 95% CI 0.2 to 0.7, p=0.003), number of days with ulcers (OR 0.4, 95% CI 0.2 to 0.8, p=0.006), sought treatment before coming into clinics (OR 0.07, 95% CI 0.002 to 0.7, p=0.005) and being unqualified worker (OR 2.5, 95% CI 0.9 to 6.7 p=0.05). Multivariate analyses revealed that increased days with ulcers (OR 0.1, 95% CI 0.04 to 0.5, p=0.002) and ulcer pain intensity (OR 0.08, 95% CI 0.007 to 1.1, p=0.05) remained significantly associated with decreased odds of TV infection. Men from the Sotho ethnic group were eight times more likely to have TV infection (OR 8.6, 95% CI 1.3 to 55.7, p<0.02) than men from the other ethnic groups.

CONCLUSION

HIV-positive men with severe ulceration should be screened and treated for TV to minimise HIV transmission to uninfected partners.

Evaluating the utility of syndromic case management for three sexually transmitted infections in women visiting hospitals in Delhi, India

Utility of syndromic case management (SCM) in women visiting obstetrics & gynecology department needs to be evaluated as it is subjective and imperfect. Consequently, antibiotic resistance has accelerated along with increased risk of infection to the partners. To understand the effectiveness and/or inadequacies of SCM, 11000 women were recruited and examined by clinicians for infection by Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Trichomonas vaginalis (TV), Bacterial vaginosis (BV) and others. Amongst these patients, 1797 (16.3%) reported vaginal discharge (VD). Other symptoms included: vaginitis (97%), cervicitis (75%), genital ulcers (60%), abnormal vaginal discharge (55%) and lower abdominal pain (48%). The patients were treated for single or co-infections using pre-packed National Aids Control Program III STI/RTI Kits. However, based on PCR diagnostics, 1453/1797 (81%) subjects were uninfected for NG/TV/CT. Amongst 344 (19%) infected patients, 257 (75%) carried infection with single pathogen (TV/NG/CT) while 87/344 (25%) were co-infected with multiple pathogens. Prevalence of TV, NG & CT was 4%, 7% and 8% respectively. Co-infection with CT + NG was highest, 51% (44/87), whereas, co-infection with CT + TV was 21% and NG + TV was 18% while co-infection with all three pathogens was 1.3%. We conclude that SCM is imprecise and successful intervention requires accurate and confirmatory diagnostic approach.

Microscopy and culture for Trichomonas vaginalis: are both required?

Many genitourinary medicine clinics have stopped routinely performing both wet preparation microscopy and cultures to diagnose Trichomonas vaginalis (TV). Our directorate stopped microscopy when screening asymptomatic women. This audit considers whether both tests continue to be warranted for symptomatic female patients. The discrepancy between microscopy and culture results leads us to recommend that both remain necessary. Sampling standardization and improved documentation are discussed.

Effect of Anapsos® in a murine model of experimental trichomoniasis

Immunomodulator effect of Anapsos (Polypodium leukotomas extract) in NMRI (US Naval Medical Research Institute) outbred mice infected by the intraperitoneal route with 10(7) Trichomonas vaginalis has been tested. Gross histopathologic changes in abdominal organs and mortality rate, as a consequence of the pathogenicity of the protozoa and the immune response of the host, were evaluated. Among the different treatment regimes assayed, Anapsos at doses of 20 mg/Kg/day administered for 10 days before infection decreases the parasite pathogenicity index (PI) in the treated animals when compared to those of the untreated control group. The immunosuppressor treatments with azathioprine (100 mg/Kg/day x 1), cyclophosphamide (100 mg/Kg/day x 1), and FK-506 (10 mg/Kg/day x 10) significantly decreased the PI, while an immunostimulant treatment with glycophosphopeptical (13 mg/Kg/day x 10) increased it. These assays have shown the usefulness of the murine model of experimental trichomoniasis for the study of immunomodulator activity of natural or synthetic drugs.

Anti-Trichomonas vaginalis activity from triterpenoid derivatives

Trichomonas vaginalis is a flagellated parasite that causes trichomonosis, the most common non-viral sexually transmitted disease (STD) in the world. Worryingly, trichomonosis is associated to increased transmission of HIV. Due to high frequency of the infection during pregnancy and the development of metronidazole-resistant isolates, therapeutic alternatives to 5-nitroimidazole are being searched. Triterpenes are natural products presenting several biological activities such as anti-protozoal activity. The aim of this study was to evaluate the in vitro anti-T. vaginalis activity from betulinic and ursolic acids, as well as semisynthetic derivatives obtained. Compounds obtained from betulinic acid presented better activity than those from ursolic acid. Piperazine derivatived from betulinic acid presented minimum inhibitory concentration (MIC) value of 91.2 μM, and the kinetic growth curve performed with parasites treated with this most active compound revealed complete inhibition of trophozoite proliferation at 2 h of incubation and total abolition of trophozoite growth in 24 h, revealing that the piperazine derivative is an efficient trichomonacidal molecule. The same compound promoted total erythrocyte lysis and lactate dehydrogenase (LDH) liberation of 83 and 100% (at 45.6 and 91.2 μM, respectively), indicating parasite membrane damage. The piperazine derivative demonstrated cytotoxic effect against the HMVII and HeLa cell lineages at the MIC value. This is the first report of semisynthetic triterpenoid derivatives with anti-T. vaginalis activity, revealing the high potential of these compounds as trichomonacidal agents.

The antimicrobial peptide, shrimp anti-lipopolysaccharide factor (SALF), inhibits proinflammatory cytokine expressions through the MAPK and NF-κB pathways in Trichomonas vaginalis adherent to HeLa cells

Trichomonas vaginalis is a parasitic protozoan that causes sexually transmitted infections (STIs) worldwide. The infection is dangerous and easily spreads within a community. Also, some cases of drug resistance were reported. Previously, we reported that the shrimp anti-lipopolysaccharide factor (SALF), an antimicrobial peptide of 24 amino acids, modulates inflammatory responses and inhibits T. vaginalis growth. To date, there is no report on the mechanism of SALF's actions in T. vaginalis' adherence to HeLa cells. In this research using an ELISA, we found that the SALF downregulated the release of proinflammatory cytokines (tumor necrosis factor (TNF)-α, interleukin (IL)-1α, IL-6, IL-8, and monocyte chemoattractant protein (MCP)-1) secreted by T. vaginalis which was adhering to HeLa cells. We also performed real-time PCR experiments to determine the roles of the SALF in the expressions of several proinflammatory genes. Through a Western blot analysis, we determined that SALF treatment inhibited T. vaginalis-treated HeLa cells through the p38 and NF-κB pathways. Furthermore, we used different inhibitors to confirm the pathway by ELISA and Western blotting. Taken together, it is apparent that the SALF suppresses T. vaginalis-induced secretion of proinflammatory cytokines by HeLa cells by acting through the p38 and NF-κB pathways.

[Procedure for Trichomonas vaginalis cultivation]

The investigation was undertaken to design a nutrient medium that could reduce the duration of a culture test in the diagnosis of trichomoniasis and to comparatively evaluate its effectiveness. A procedure was proposed to cultivate Trichomonas vaginalis, which was based on the use of the nutrient medium containing casein hydrolysate, yeast autolysate, and serum, added by 0.6 ml of liquid Ferrum Lec (iron (III) hydroxide polyisomaltose), which reduced the time taken to identify Trichomonas vaginalis (on day 2). At the same time, the higher content of iron [III] hydroxide with polyisomaltose was shown to produce no positive effect.

[Cryopreservation of Trichomonas vaginalis and its influence factors]

Different concentrations of dimethylsulfoxide (DMSO) and glycerol, various densities of Trichomonas vaginalis trophozoites and duration of storage were used to study the effects on the cryopreservation of T. vaginalis at -78 degrees C. The optimal densities of trichomonads for cryopreservation were (1-2) x10(6)/ml. Glycerol and DMSO showed a high protective effect, with a maximum effect at a concentration of 10%, and the survival rates were 38.0% and 31.7%, respectively. There was no significant difference between them (P > 0.05). The results showed that the above optimized factors can provide a good protection in short-term (1-16 weeks) cryopreservation, and the trichomonads can be incubated to a logarithmic growth phase at 37 degrees C.

[Influence of iron ion on the growth of Trichomonas vaginalis in vitro]

OBJECTIVE

To study the influence of iron ion on the growth of Trichomonas vaginalis in vitro.

METHODS

Quantitative pure incubation of T. vaginalis trophozoites with an initial density of 1 x l0(5)/ml was carried out at 37 degrees C in TYM (trypticase-yeast extract-maltose) medium (pH 6.0) with additional 100, 200, 300, and 400 micromol/L iron ion, respectively, and in TYM medium without additional iron ion as control The numbers of live and dead trichomonads were counted under an optical microscope after trypan blue staining, and the growth curve and survival rate of T. vaginalis were drawn to calculate the generation time of T. vaginalis. The minimal lethal concentration (MLC) of metronidazole was tested by serial dilution method when the trophozoites of T. vaginalis were incubated in TYM medium with 200 micromol/L iron ion and in control group without additional iron ion.

RESULTS

The maximum densities of 2.9 x 10(6), 3.2 x 10(6), 3.1 x 10(6), and 2.8 x 10(6)/ml were obtained when the trophozoites were incubated for 40 h in TYM medium with 100, 200, 300, and 400 micromol/L iron ion, respectively, while the maximum density was achieved at 50 h in the control, which was 2.5 x l0(6)/ml. The generation time was (6.8 +/- 0.7) h in 400 micromol/L iron ion group, longer than those in the groups with 100-300 micromol/L iron ion, which were (4.8 +/- 0.3), (4.8 +/- 0.2), and (5.0 +/- 0.4) h, respectively (P < 0.05). While the generation times in 100-400 micromol/L groups were all shorter than that of the control [(10.2 +/- 3.1) h] (P < 0.05). MLC of metronidazole for T. vaginalis in TYM medium with 200 micromol/L iron ion was (23.44 +/- 11.56) microg/ml, significantly lower than that of the control [(31.25 +/- 15.44) microg/ml] (P < 0.05).

CONCLUSION

In TYM medium with 100-400 micromol/L iron ion, T. vaginalis trophozoites reproduce faster, and the MLC of metronidazole to the parasites is lower.

[Comparative effect of different media in in vitro cultivation of Trichomonas vaginalis]

OBJECTIVE

To investigate the optimal condition for in vitro cultivation of Trichomonas vaginalis for obtaining a better harvest of T. vaginalis.

METHODS

An isolate of T. vaginalis from clinical specimens was cultivated in three different media with initial inoculation of 9.0 x 10(4)/ml under pH 5.6.

RESULTS

There was distinct difference after 96 h incubation in the cumulative harvest of T. vaginalis. The highest harvest was received in cysteine/liver/peptone/maltose medium, followed by the liver/peptone/maltose medium and soybean/liver/peptone/maltose medium.

CONCLUSION

The cysteine/liver/peptone/maltose medium may be a suitable environment for in vitro multiplication of T. vaginalis.

In vitro activity of Arbutus unedo leaf extracts against Trichomonas vaginalis trophozoites

Trichomonas vaginalis (T. vaginalis) is a flagellated protozoan commonly causing sexually transmitted disease. T. vaginalis infections are treated with a 5-nitroimidazole derivate. However, drug resistance has been known to occur for a long time and new alternatives are under investigation. Arbutus unedo is a wild plant mainly growing in maquis and rocky places of the seaboard in Southern Europe. In our study, ethanolic, water, hexane and ethyl acetate extracts of Arbutus unedo leaves were tested in vitro against T. vaginalis trophozoites and the ethyl acetate extract of Arbutus unedo leaves was found to be effective (Growth inhibition rate (GI): 100%, at the concentration of 500 microg/ml). It may be a promising anti-trichomonacidal agent in the future and further experiments are needed.

Effect of Mexican medicinal plant used to treat trichomoniasis on Trichomonas vaginalis trophozoites

Crude methanolic extracts from 22 Mexican medicinal plants were screened for antitrichomonal activity against Trichomonas vaginalis, which is the etiological agent of trichomoniasis. Among the plants tested Carica papaya and Cocos nucifera showed the best antitrichomonal activity with IC(50) values of 5.6 and 5.8 microg/ml, respectively. The extracts of Bocconia frutescens, Geranium mexicanum, and Lygodium venustum showed moderate activity with IC(50) values ranging from 30.9 to 60.9 microg/ml. All the other plant extracts were inactive (IC(50)>100 microg/ml). All extracts tested were less active than metronidazole (IC(50) 0.037 microg/ml), an antiprotozoal drug used as positive control. The results of the antiprotozoal screening support the popular uses of five of the plants tested for the treatment of some urogenital tract disorders in Mexican traditional medicine. However, seeds of Carica papaya and aerial parts of Bocconia frutescens should be used in herbal medicine with care to avoid toxicity.

A simple and rapid method for cryopreservation of Trichomonas vaginalis

A pellet freezing method, one type of rapid freezing protocol, was established for Trichomonas vaginalis. As cryoprotectants, 5-20% dimethylsulfoxide (DMSO), ethylene glycol, propylene glycol, and glycerol were used. Of these, DMSO showed a high protective effect, with a maximum effect at a concentration of 20%. No effect of equilibration time was recognized with any of the cryoprotectants. Therefore, the optimal condition was deemed 20% DMSO without equilibration. The pellet freezing method was also compared with the conventional slow cooling protocol. The survival rate was 73 +/- 8% with the slow cooling protocol and 48 +/- 4% with the pellet freezing method. The delay in growth with the pellet freezing method was no more than 5.4 h compared with the slow cooling protocol, suggesting its validity as a technique for cryopreservation of T. vaginalis.

Activation of Multifarious Transcription of an Adhesion Protein ap65-1 Gene by a Novel Myb2 Protein in the Protozoan Parasite Trichomonas vaginalis

Multifarious transcription of the adhesion protein ap65-1 gene in the human pathogen, Trichomonas vaginalis, is critically regulated by the coordination of two similar but opposite oriented DNA regulatory regions, MRE-1/MRE-2r and MRE-2f, both of which are binding sites for multiple Myb-like proteins. In the present study, MRE-1/MRE-2r was demonstrated to be composed of multiple overlapping promoter elements, among which the entire region is required for growth-related ap65-1 transcription, and the 5'-MRE-1 antagonizes the suppressive activity of the 3'-MRE-2r in iron-inducible transcription. The recombinant Myb2 protein derived from a previously identified myb2 gene was demonstrated to recognize distinct sequence contexts in MRE-2r and MRE-2f, whereas Myb2 in the nuclear lysate preferentially binds to MRE-2f to MRE-2r. Iron repletion resulted in persistent repression of the myb2 gene, and temporal activation/deactivation of Myb2 promoter entry, which was also activated by prolonged iron depletion. The hemagglutinintagged Myb2 when overexpressed during iron-depleted conditions facilitated basal and growth-related ap65-1 transcription to a level that was achieved in iron-replete cells, whereas ironinducible ap65-1 transcription was abolished with knockdown of Myb2. These findings demonstrated that Myb2 is involved in activation of growth-related and iron-inducible transcription of the ap65-1 gene, possibly through differential promoter selection in competition with other Myb proteins.

Hydrogenosomal activity of Trichomonas vaginalis cultivated under different iron conditions

To evaluate whether iron concentration in TYM medium influence on hydrogenosomal enzyme gene expression and hydrogenosomal membrane potential of Trichomonas vaginalis, trophozoites were cultivated in irondepleted, normal and iron-supplemented TYM media. The mRNA of hydrogenosomal enzymes, such as pyruvate ferredoxin oxidoreductase (PFOR), hydrogenase, ferredoxin and malic enzyme, was increased with iron concentrations in T. vaginalis culture media, measured by RT-PCR. Hydrogenosomal membrane potentials measured with DiOC6 also showed similar tendency, e.g. T. vaginalis cultivated in iron-depleted and iron-supplemented media for 3 days showed a significantly reduced and enhanced hydrogenosomal membrane potential compared with that of normal TYM media, respectively. Therefore, it is suggested that iron may regulate hydrogenosomal activity through hydrogenosomal enzyme expression and hydrogenosomal membrane potential.

Failure to detect urethral Trichomonas vaginalis in Japanese men with or without urethritis

AIM

Trichomonas vaginalis may cause symptomatic or asymptomatic urethritis in men. There are few recent studies on the prevalence of T. vaginalis infection in Japanese men, and quantification of the number of cases of urethritis attributable to this pathogen has not been performed in Japan. The aim of this study was to determine the prevalence and morbidity of T. vaginalis infection in Japanese men.

METHODS

One hundred subjects with or without urethritis were examined for the presence of urethral T. vaginalis using culture swabs.

RESULTS

Urethral swabs from all subjects were negative for T. vaginalis.

CONCLUSION

These results indicate Japanese men, including those with urethritis, have a low incidence of urethral T. vaginalis infection or colonization. T. vaginalis appears to be an uncommon pathogen for male urethritis in Japan.

[Molecular and chemical mechanism of Trichomonas vaginalis-induced contact-dependent cytotoxicity]

Trichomonas vaginalis parasitizes in human genitourinary tract. The protozoon adhering to target cell plays a critical role in its contact-dependent cytotoxicity. The enzymes synthesized by T.voginalis can hurt vaginalis epithelial cells (VECs) directly. The focal immune reaction in the location parasitized by the parasite may provide an immunologic protection. Meanwhile, inflammatory factors and immune cells may aggravate the situation. In general, the T. vaginalis-induced contact-dependent cytotoxicity is a result of the involvement of some molecular and chemical factors.

Viability of Trichomonas vaginalis in urine: epidemiologic and clinical implications

The impact of the viability of Trichomonas vaginalis in urine on wet mount, culture, and PCR methods was assessed. To minimize the chance of false-negative results, urine specimens should be processed within 30 min of specimen collection and maintained at 37 degrees C, since temperature appears to affect the viability of Trichomonas.

Fe-hydrogenase maturases in the hydrogenosomes of Trichomonas vaginalis

Assembly of active Fe-hydrogenase in the chloroplasts of the green alga Chlamydomonas reinhardtii requires auxiliary maturases, the S-adenosylmethionine-dependent enzymes HydG and HydE and the GTPase HydF. Genes encoding homologous maturases had been found in the genomes of all eubacteria that contain Fe-hydrogenase genes but not yet in any other eukaryote. By means of proteomic analysis, we identified a homologue of HydG in the hydrogenosomes, mitochondrion-related organelles that produce hydrogen under anaerobiosis by the activity of Fe-hydrogenase, in the pathogenic protist Trichomonas vaginalis. Genes encoding two other components of the Hyd system, HydE and HydF, were found in the T. vaginalis genome database. Overexpression of HydG, HydE, and HydF in trichomonads showed that all three proteins are specifically targeted to the hydrogenosomes, the site of Fe-hydrogenase maturation. The results of Neighbor-Net analyses of sequence similarities are consistent with a common eubacterial ancestor of HydG, HydE, and HydF in T. vaginalis and C. reinhardtii, supporting a monophyletic origin of Fe-hydrogenase maturases in the two eukaryotes. Although Fe-hydrogenases exist in only a few eukaryotes, related Narf proteins with different cellular functions are widely distributed. Thus, we propose that the acquisition of Fe-hydrogenases, together with Hyd maturases, occurred once in eukaryotic evolution, followed by the appearance of Narf through gene duplication of the Fe-hydrogenase gene and subsequent loss of the Hyd proteins in eukaryotes in which Fe-hydrogenase function was lost.

Alternative pathway of metronidazole activation in Trichomonas vaginalis hydrogenosomes

Metronidazole and related 5-nitroimidazoles are the only available drugs in the treatment of human urogenital trichomoniasis caused by the protozoan parasite Trichomonas vaginalis. The drugs are activated to cytotoxic anion radicals by their reduction within the hydrogenosomes. It has been established that electrons required for metronidazole activation are released from pyruvate by the activity of pyruvate:ferredoxin oxidoreductase and transferred to the drug by a low-redox-potential carrier, ferredoxin. Here we describe a novel pathway involved in the drug activation within the hydrogenosome. The source of electrons is malate, another major hydrogenosomal substrate, which is oxidatively decarboxylated to pyruvate and CO2 by NAD-dependent malic enzyme. The electrons released during this reaction are transferred from NADH to ferredoxin by NADH dehydrogenase homologous to the catalytic module of mitochondrial complex I, which uses ferredoxin as electron acceptor. Trichomonads acquire high-level metronidazole resistance only after both pyruvate- and malate-dependent pathways of metronidazole activation are eliminated from the hydrogenosomes.

The combined effect of two aqueous extracts on the growth of Trichomonas vaginalis, in vitro

In this study a trial was performed to determine the effect of a combination of two aqueous extracts of two medicinal plants namely the violet, Viola odorata, and the rue, Ruta graveolens, with concentrations of 0.15625, 0.3125, 10-20 mg/cm3 on the growth of Trichomonas vaginalis cultured in (CM161) medium during periods of 24, 48, 72, and 96 hrs. The results showed that there is a variation of inhibition. Complete inhibition was seen with a concentration 10 mg/cm3 for 48 hrs. During the 96 hr. Period, 81% inhibition was achieved at a concentration of 0.3125mg /cm3 , and 75% at a concentration of 0.15625mg/cm3. A variety of interaction was observed in combination of violet and rue. Significant synergism was achieved at a concentration of 20 mg/cm3, and a suggestive synergism was achieved with 10 mg /cm3 In addition, partial antagonism occurred at a concentration of 0.15625mg /cm3 and an antagonism at 0.3125mg /cm3 was achieved.

[Investigation of the prevalence of Trichomonas vaginalis in women with complaints of vaginal discharge and itching]

Trichomonas vaginalis (T. vaginalis) is the most common pathogen that is sexually spread in women. In this study, the presence of Trichomonas vaginalis was investigated in patients with vaginal discharge and itching who presented at the polyclinic of the Mustafa Kemal University Medical Faculty Department of Gynecology. These women were between 20-40 years of age. During gynecologic examination of patients, vaginal fluid samples were collected with swaps from the speculum and fornics to two tubes that contained sterile saline. One of the vaginal discharges collected with swaps was used for direct microscopic examination and Giemsa staining. The other one was used for culturing for T. vaginalis in Trichomonas medium that contained horse serum and antibiotics. While the fre-quency of T. vaginalis was found to be 1.81% (5 of the 275 samples) by the direct microscopic examination and Giemsa stain, this ratio was 2.18% (6 of the 275 samples) by the culture method. In conclusion, it was decided to use the culture method in diagnosis of T. vaginalis in addition to direct microscopic examination. This was the first study of T. vaginalis infection in our region and it was compared with other studies carried out in other regions of Turkey. Our results were somewhat lower than those in other regions.

Nonoxynol 9 as an additive therapy in metronidazole-resistant cases of vaginal trichomoniasis

The present study was conducted on 30 female patients with metronidazole resistant vaginal trichomoniasis to investigate the efficacy of nonoxynol 9 (N-9), a non hormonal contraceptive with spermicidal effect, as an additive therapy to metronidazole (MNZ). Study population were randomly divided into 3 groups according to treatment regimen: G.I: patients received high dose MNZ (2 g daily for 7 days) n = 10; G. II: patients received (100 mg N-9 vaginal suppository daily for 7 days) n = 10; G. III: patients receiving conventional MNZ dose (1 g daily for 7 days) plus (a 100 mg N-9 suppository for 7 days) n = 10. Clinical and parasitological evaluation of cure was performed at return visits 1, 2, 4 and 6 weeks post treatment. Negative T. vaginalis vaginal smears were ensured by direct microscopic visualization and In Pouch TV culture technique. Most of the patients were in the 30-39 years age group (60%) and burning was the most frequent symptom (96.67%). The cure rates were 70%, 40% and 90% for Gs I, II & III respectively, while adverse effects of treatment were recorded most frequently by patients of G.I. So, MNZ resistant trichomoniasis incidence seems to be on the rise. Topical therapy alone has a low cure rate while combined oral conventional doses of MNZ and intravaginal nonoxynol 9 treatment appears to be a good clinical trial with fairly good cure rate thus, avoiding the adverse side effects of high doses MNZ therapy and T. vaginalis health hazards potentiality.

[Comparative assessment of the diagnostic value of the laboratory diagnostic methods for trichomoniasis]

The authors compared the sensitivity and specificity of currently available methods for laboratory diagnosis of trichomoniasis, by examining 971 persons. The highest frequency of T. vaginalis was detected by studies of a stained smear (37.4%), culture tests (19.0%); polymerase chain reaction (PCR) (17.1%), immunofluorescence tests (12.7%), wet smear test (2.7%). Enzyme immunoassay yielded positive results in 36.2% of cases. The use of PCR and culture tests frequently provided similar results (92.0%). The authors have proposed an algorithm of a laboratory study including wet smear microscopy, PCR, and culture tests as basic methods. They have noted the higher detection rates of T. vaginalis when analyzing during draining physiotherapeutic procedures (endocervical vibratory massage with vacuum aspiration in females and pneumovibratory massage of the prostate with endourethral chemotrypsin electrophoresis in males).

Increased sensitivity of Trichomonas vaginalis isolation from vaginal secretions by subsequent blind passage of preliminary negative cultures

Trichomonas vaginalis is a vaginal protozoon causing the most prevalent nonviral sexually transmitted disease. Culture is considered as the most reliable and gold standard among conventional diagnostic methods in the detection of T. vaginalis. In the present study, the diagnostic effect of subsequent blind culturing of vaginal secretion samples in Diamond's complete medium at every 48 h was investigated in 93 women. Vaginal secretion samples were examined by wet mount and inoculated into Diamond's complete medium. All tubes were subcultured to a new culture tube blindly 5 times at 48-h interval and checked microscopically everyday for the presence of T. vaginalis trophozoites. Three of 93 women were found to be positive both by wet mount and standard culture methods. Five more positive results were detected with subsequent blind culturing among 90 negative results. This system appears to be a useful method for the detection of T. vaginalis.

HeLa cell nucleus, a source of thymidine for Trichomonas vaginalis growing in vitro

Trichomonas vaginalis is a parasitic protist incapable of de novo purine and pyrimidine biosynthesis. The lack of these de novo syntheses of nucleotides is supplemented with purine and pyrimidine salvage pathways. Likewise, T. vaginalis is incapable of converting its ribonucleotides to deoxyribonucleotides. Therefore, the parasite must rely on the salvage of exogenous deoxyribonucleosides for DNA synthesis. It has been demonstrated that the parasite can incorporate external adenine and guanine in vitro, but no in vivo nucleotide source has been identified so far. Accordingly, we set out to determine if the parasite could incorporate 3H-thymidine from the nuclei of a cervical-derived cell line into its own DNA. By light and electron microscopy we found that the parasite was able to interact directly, both with mechanically isolated HeLa cell nuclei and with the nuclei released after the disruption of HeLa cell monolayers by the parasite. This study shows that T. vaginalis was capable of incorporating 3H-thymidine from labeled HeLa cells into its own DNA suggesting that the nuclei of this cervical cell line could be an in vivo source of nucleotides for T. vaginalis.

Growth patterns and antigenic analysis of Egyptian Trichomonas vaginalis isolates

The vaginal washouts from symptomatic and asymptomatic patients were examined by wet mount examination and culture on modified TYM medium. Among the 320 cases examined, 10 were positive for T. vaginalis trophozoites by wet mount examination and culture. Modified TYM medium proved very satisfactory for isolation as well as maintenance of the 10 T. vaginalis isolates. Comparison between the growth patterns of all isolates, by counting the number of viable organisms every 24 hours for 7 days, showed that there is a wide variability in the growth characteristics, as regards lengths of log phase, growth peaks reached, generation times, division rate and number of divisions. Antigenic differentiation of the 10 T. vaginalis isolates through SDS-PAGE demonstrated a total of 34 bands using 10% resolution gel. The bands ranged in molecular weight from 12 to 189 KDa. Most of the bands were common among several isolates while isolate 2 appeared different than other isolates with two characteristic bands; one at 136 KDa and the other at 25 KDa. Also, isolates 4 and 8 had characteristic bands at 163 KDa and 189 KDa respectively.

Silencing the ap65 gene reduces adherence to vaginal epithelial cells by Trichomonas vaginalis

Host parasitism by Trichomonas vaginalis is complex and in part mediated by adherence to vaginal epithelial cells (VECs). Four trichomonad surface proteins bind VECs as adhesins, and AP65 is a major adhesin with sequence identity to an enzyme of the hydrogenosome organelle that is involved in energy generation. In order to perform genetic analysis and assess the role of AP65 in T. vaginalis adherence, we silenced expression of ap65 using antisense RNA. The gene for ap65 was inserted into the vector pBS-neo in sense and antisense orientations to generate plasmids pBS-neoS (S) and pBS-neoAS (AS), respectively. Trichomonads were then transfected with S and AS plasmids for selection of stable transfectants using Geneticin, and the presence of plasmid in transfectants was confirmed by polymerase chain reaction of the neo gene. Reverse transcription polymerase chain reaction and Northern blot analysis showed decreased amounts of ap65 transcript in AS transfected parasites. Growth kinetics of the antisense-transfected and wild type organisms were similar, suggesting that silencing AP65 did not affect overall energy generation for growth. Immunoblot analysis using monoclonal antibody (mAb) to AP65 of AS transfectants showed decreased amounts of AP65 when compared to wild type or S transfectants. Not unexpectedly, this corresponded to decreased amounts of AP65 bound to VECs in a functional ligand assay. Reduction in parasite surface expression of AP65 was related to lower levels of adherence to VECs by AS-transfectants compared to control organisms. Antisense silencing of ap65 was not alleviated by growth of trichomonads in high iron, which up-regulates transcription of ap65. Our work reaffirms the role for AP65 as an adhesin, and in addition, we demonstrate antisense RNA gene silencing in T. vaginalis to study the contribution of specific genes in pathogenesis.

Antiparasitic activity of highly conjugated pyrimidine-2,4-dione derivatives

4-[2-(1,3-Dimethyl-5-nitro-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-yl)vinyl]benzaldehyde was synthesized in four steps from 6-methyl-1H,3H-pyrimidine-2,4-dione. This aldehyde was functionalized by various substituted anilines or substituted benzylamines. Antiparasitic activities of the corresponding azomethines were assessed against Plasmodium falciparum, Trichomonas vaginalis and Leishmania infantum compared to their toxicity versus human cells.

Detection of trichomoniasis in vaginal specimens by both conventional and modern molecular tools

Out of 23 symptomatic cases 21 specimens were positive for T. vaginalis by one or more methods. 21 were positive by PCR (91.3%) and 17 (72.9%) by culture, 14 (60.8%) by Acridine orange (AO) stain and 13 (56.5%) by wet mount microscopy. The PCR detected all the positive cases and no PCR negative cases proved to be positive by any other technique. So, it is the test of choice for diagnosis of trichomoniasis. The modified Diamond's media proved to be highly sensitive (80.95%) and the results of the culture were significantly associated with those of PCR. The results of both wet mount and AO stain were insignificantly associated. The wet mount although widely used, easy, rapid and inexpensive yet, it has low sensitivity. So, negative cases should be repeated by either culture or PCR.

Production of ammonia by Tritrichomonas foetus and Trichomonas vaginalis

Production of ammonia is difficult to find among the various studies of amino acid metabolism in protozoa. Several studies suggest that catabolism of arginine to ammonium is important for the growth of trichomonads. Trichomonads are amitochondriate zooflagellates that thrive under microaerophilic and anaerobic conditions. The authors were able to detect accumulation of ammonium ions and ammonia in cultures of Tritrichomonas foetus and Trichomonas vaginalis, including those resistant to metronidazole. Ammonium ions and ammonia were detected using the indophenol colorimetric method. Cells incubated overnight under an ambient oxygen gas phase had 0.9 mM soluble ammonium (NH(4)(+) and NH(3)) or a 20 % greater concentration of ammonium relative to sterile growth medium that had been incubated similarly. Production of ammonia itself was confirmed by analysis of a wick that was moistened with sulfuric acid (20 mM) and placed above the liquid in sealed cultures of a strain of Trichomonas vaginalis. The wicks from these cultures captured the equivalent of 0.048 mM volatile ammonia (NH(3)) from the liquid as compared to 0.021 mM volatile ammonia from sterile medium after overnight incubation. Intact trichomonads, 0.7 x 10(6) cells ml(-1) equivalent to 0.7 mg protein ml(-1), incubated in Doran's buffer with or without (1 mM) L-arginine produced significant amounts of soluble ammonium (0.07 mM and 0.04 mM, respectively) during 60 min. The results indicate that ammonium ions and the more irritating ammonia are significant metabolites of trichomonads. In addition, based upon end-product amounts, it appears that the rate of arginine metabolism is of the same order of magnitude as that for carbohydrate metabolism by trichomonads.

Heme-iron increases levels of AP65-mediated adherence by Trichomonas vaginalis

Trichomonas vaginalis is a protozoan responsible for the number one, non-viral sexually transmitted disease. Surface proteins (AP65, AP51, AP33 and AP23) mediate adherence to vaginal epithelial cells (VECs). Iron increases growth of trichomonads and synthesis and surface placement of adhesins. We observed by immunofluorescence using monoclonal antibody (mAb) 12G4 the placement of AP65 on surfaces of trichomonads supplemented with hemoglobin or hemin as a source of iron. We, therefore, tested the hypothesis that heme-bound iron is an alternative source of iron important to trichomonal growth and regulation of expression of the adhesin genes. Here we show that the inhibition of parasite growth by the iron chelator 2,2-dipyridal is rescued by hemoglobin or hemin, but not protoporphyrin IX. Importantly, trichomonads grown in iron-limiting medium supplemented with free iron, hemoglobin and hemin had elevated levels of ap65 transcript that were 12.6-, 12.3- and 9.2-fold higher, respectively, than low-iron organisms, as determined by RT-PCR. Similarly, the amounts of AP65 were 8.9-, 11.2-, and 4.8-fold higher in parasites grown in free iron, hemoglobin and hemin, respectively, than organisms in low-iron medium. The heme-iron-regulated AP65 increased adherence of parasites to immortalized VECs. Not surprisingly, parasites pretreated with anti-AP65 serum IgG had decreased adherence compared to organisms incubated with prebleed serum IgG. These data illustrate that heme-bound iron is a source of iron similar to lactoferrin. This work extends our findings about the multiple sources of iron for regulating virulence genes of T. vaginalis.

Trichomonas vaginalis virulence against epithelial cells and morphological variability: the comparison between a well-established strain and a fresh isolate

The FMVI strain of Trichomonas vaginalis was freshly isolated from an asymptomatic patient, and its morphological properties and virulence in vitro compared with the well-established JT strain. The morphological variability of the parasites was assessed by differential interference microscopy and both scanning and transmission electron microscopy. The FMV1 strain presented nearly 20% amoeboid cells whereas the JT strain presented high percentages of ellipsoid but no amoeboid cells. The FMV1 morphotype population was unaltered after at least 1 year of subculturing. Electron microscopy revealed that this strain produced numerous pseudopod structures which mediated intimate contact and interdigitation among trophozoites. Dead FMV1 parasites were often phagocytosed by conspecific cells. We also compared the cytolytic capacity of these two populations against epithelial MDCK cells and its contact dependence. The FMV1 strain rapidly adhered to plastic or glass surfaces and to MDCK monolayers. This strain destroyed about 93% of the epithelial cells in 90 min whereas the cytolytic activity of the JT parasites was very much lower (about 41%). Parasite supernatants displayed no cytolytic activity, indicating contact-mediated lysis. The protozoan virulence in vitro did not correlate well with the clinical observations. The implications of these results are discussed.

Involvement of multiple DNA elements in iron-inducible transcription of the ap65-1 gene in the protozoan parasite Trichomonas vaginalis

A reputed iron-responsive region, which contains multiple nuclear protein-binding DNA sequences, was shown previously to regulate iron-inducible transcription of the ap65-1 gene in the protozoan pathogen, Trichomonas vaginalis. These DNA sequences include two overlapping MYB recognition elements (MRE-1/MRE-2r) and three abutted T-tract elements. Additional nuclear protein-binding DNA sequences flanking the 5' (AGTGAAGTGA) and 3' (MRE-2f) of the iron-responsive region were identified in the present study. A stable promoter assay and primer extension revealed that transcriptional activity of the ap65-1 promoter is iron inducible as well as growth related, being lowest in the early logarithmic phase and highest in the mid-logarithmic phase. Subsequent mutational analysis of individual DNA elements of the ap65-1 promoter suggests that closely spaced T-tract elements together with an intervening GAAGGAAG sequence within the iron-responsive region are most critical for regulation of overall transcriptional activity, whereas an additional AGTGAAGTGA and MRE-2f together with an upstream T-rich region are required for optimal iron-inducible activity, and the MRE-1/MRE-2r overlap is only involved in growth-related activity. These observations suggest that expression of the ap65-1 gene is dynamically regulated under various growth conditions via interactions among multiple DNA regulatory elements.

Trichomonas vaginalis: Determination of Acid Phosphatase Activity as a Pharmacological Screening Procedure

A simple method to screen trichomonacides, based on the quantification of acid phosphatase (AP) activity, has been designed. Using p-nitrophenyl phosphate as chromogenic substrate, we first determined the optimal conditions for enzyme reaction. After seeding, a linear correlation between number of trichomonads and optical densities at 405 nm was obtained at 24 hr but not at 48 hr. Then, the inhibitory effect of metronidazole was assessed both by microscope counts and by AP determination. Similar values for 50% inhibitory concentrations (2.6 microM), with 95% confidence limits of 1.91-3.33 for microscopic and 2.21-3.05 for colorimetric method, were obtained. We concluded that the colorimetric method described in this investigation is suitable for pharmacological studies and for the screening of new, potential antitrichomonal agents.

The in vitro effect of Assafoetida on Trichomonas vaginalis

Assafoetida is an oleo-gum resin obtained from the roots and stems of many Ferula species such as F. foetida Regel, F. asafoetida Linn, F. alliacea Boiss. and F. narthex Boiss, family Umbelliferae (carrot family), plants growing indigenously in Iran, Afghanistan and north of India. Assafoetida is commonly used as a flavoring agent in food and as a traditional medicine for many diseases in many parts of the world. In this work, the effect of Assafoetida on growth of Trichomonas vaginalis in vitro was studied and compared to metronidazole as a reference drug. It showed that Assafoetida had a potent antiparasitic effect on T. vaginalis compared to metronidazole, thus, worth further investigation to study its applicability in treatment of parasitic infections.

Adenosine is the primary precursor of all purine nucleotides in Trichomonas vaginalis

Trichomonas vaginalis, a parasitic protozoan and the causative agent of trichomoniasis, lacks de novo purine nucleotide synthesis and possesses a unique purine salvage pathway, consisting of a bacterial type purine nucleoside phosphorylase and a purine nucleoside kinase. It is generally believed that adenine and guanine are converted to their corresponding nucleosides and then further phosphorylated to form AMP and GMP, respectively, as the main as well as the essential pathway of replenishing the purine nucleotide pool in the organism. Formycin A, an analogue of adenosine, inhibits both enzymes as well as the in vitro growth of T. vaginalis with an estimated IC(50) of 0.27 microM. This growth inhibition was reversed by adding adenine to the culture medium but not by adding guanine or hypoxanthine. Furthermore, T. vaginalis can grow in semi-defined medium supplemented with only adenine but not with guanine or hypoxanthine. Radiolabeling experiments followed by HPLC analysis of the purine nucleotide pool in T. vaginalis demonstrated incorporation of [8-14C]adenine into both adenine and guanine nucleotides, whereas [8-14C]guanine was incorporated only into guanine nucleotides. Substantial adenosine deaminase activity and significant IMP dehydrogenase and GMP synthetase activities were identified in T. vaginalis lysate, suggesting a pathway capable of converting adenine to GMP via adenosine. This purine salvage scheme depicts adenosine the primary precursor of the entire purine nucleotide pool in T. vaginalis and the purine nucleoside kinase one of the most pivotal enzymes in purine salvage and a potential target for anti-trichomoniasis chemotherapy.

Morphogenesis during division and griseofulvin-induced changes of the microtubular cytoskeleton in the parasitic protist, Trichomonas vaginalis

The behavior of microtubular structures during division was followed by immunofluorescence in Trichomonas vaginalis using an anti-alpha-tubulin monoclonal antibody together with nuclear staining by DAPI, allowing us to describe successive mitotic stages. In contrast to recent reports, we showed that: (1) the microtubular axostyle-pelta complex depolymerized during division, (2) the flagella were assembled during mitosis, and (3) the flagellar number was restored in each daughter kinetid before cytokinesis. Observation of griseofulvin-treated T. vaginalis cells revealed that the elongation of the mitotic spindle or paradesmosis was not the main motile force separating the daughter kinetids to opposite poles during division, suggesting the existence of other mechanisms and/or molecules involved in this morphogenetic event. Examination of treated cells re-incubated in fresh medium showed the nucleation of microtubules radiating from the perinuclear area, the origin of which is discussed. Finally, we confirm the effectiveness of griseofulvin against T. vaginalis and propose that this antifungal drug could be a promising antitrichomonal agent.

Trichomonas vaginalis: in vitro attachment and internalization of HIV-1 and HIV-1-infected lymphocytes

Sexually transmitted diseases (STDs) caused by bacteria and protozoa play an important role in the epidemiology of human immunodeficiency virus (HIV-1) infection. Human trichomoniasis, produced by the protozoan parasite Trichomonas vaginalis, is one of the most common STDs, and is a cause of mucosal lesions in the urogenital tract, which may increase the risk for HIV infection. However, there are no reports concerning the outcome of in vitro interactions between HIV particles and trichomonads. Therefore, we incubated T. vaginalis with three subtypes of HIV-1 (A, B, and D), as well as with HIV-1-infected lymphocytes, and analyzed the interactions with immunofluorescence microscopy and transmission electron microscopy. Our results demonstrated that HIV-1 particles attach and are incorporated into T. vaginalis through endocytic vesicles and are degraded within cytoplasmic vacuoles in approximately 48 h. There was no ultrastructural evidence of HIV-1 replication in trichomonads. These results demonstrated that trichomonads may internalize and harbor HIV-1 particles for short periods of time. In addition, under in vitro conditions, T. vaginalis ingests and digests HIV-1-infected lymphocytes.

Antitrichomonal strains of Bacillus thuringiensis

Parasporal inclusion proteins from a total of 816 Bacillus thuringiensis strains isolated in Japan were examined for antitrichomonal activity against Trichomonas vaginalis. Ten strains of B. thuringiensis inhibited the growth of T. vaginalis in 48 h cultures at 37 degrees C. Moreover, the B622 and B626 strains clearly showed trichomonacidal effects against T. vaginalis. The H antigen serotypes of both strains were identified as H13/29 (pakistani/amagiensis). The parasporal inclusion protein from both strains consisted of three major polypeptides of 77, 45 and 25 kDa.

Visualization of new virus-like-particles in Trichomonas vaginalis

In the present work, we demonstrate virus-like particles (VLPs) with various morphological variations in Trichomonas vaginalis. The VLPs were distinct based on size, shape and electron density, with VLPs being either electron-dense or electron-lucent. We used electron microscopy thin sections of several T. vaginalis strains virus-infected, and also negative staining of fractions obtained after purification by CsCl buoyant density gradient centrifugation. The particles observed in fractions are identical to those previously described, but by thin sections, we found new forms. The shapes found were icosahedral, spherical and oblong, and the sizes varied from 33 to 120nm in diameter with the most common VLP being spherical and having a size range from 83 to 104nm. The VLPs were found in the cytoplasm closely associated with the Golgi complex, with some VLPs budding from the Golgi, and other VLPs were detected adjacent to the plasma membrane. Unidentified cytoplasmic inclusions were observed in the region close to the VLPs and Golgi. Clusters of the already described icosahedral virus were also observed in the cytoplasm, although less frequently. These results indicate that T. vaginalis organisms may be infected with different dsRNA viruses simultaneously.

Effect of the iron chelator deferoxamine on Trichomonas vaginalis in vitro

The effect of 10 microMol, 15 microMol, 30 microMol, and 60 microMol concentrations of deferoxamine (DFO), a clinically approved iron chelator, was determined on viability and multiplication of Trichomonas vaginalis grown in TYM axenic culture medium at 24 hours interval. DFO killed all T. vaginalis isolates with a minimum lethal concentration of 30 microMol after 48 hours culture incubation with the drug. A potent and persistent inhibitory effect of DFO on the parasite viability and multiplication was recorded throughout the study till its end, in a drug concentration and time exposure-dependent manner. Furthermore, the present work studied the proteinase activity of T. vaginalis grown for 48 hours in DFO inoculated TYM medium, and recorded a significant decrease by all drug concentrations applied in the work. Different possible mechanisms of action of DFO against T. vaginalis and its possible use for treatment of trichomoniasis are discussed.

Characterization of an ecto-phosphatase activity in the human parasite Trichomonas vaginalis

We have characterized phosphatase activity present on the external surface of Trichomonas vaginalis, using intact living parasites. This enzyme hydrolyzes the substrate p-nitrophenylphosphate (p-NPP) at a rate of 134.3+/-14.8 nmol Pi/h per 10(7) cells. This phosphatase activity decreased by increasing the pH from 6.8 to 8.4, a pH range in which cell viability was maintained for at least 1 h. Experiments using classical inhibitors of acid phosphatases, such as ammonium molybdate and sodium fluoride, as well as inhibitors of phosphotyrosine phosphatase, such as sodium orthovanadate, [monoperoxo(picolinato)oxovanadate(V)] (mpV-PIC) and [potassiumbisperoxo(1,10-phenanthroline)oxovanadate(V)] (bpV-PHEN), showed a decrease in this phosphatase activity, with different patterns of inhibition. Cytochemical analysis showed the localization of this enzyme on the parasite surface (cell body and flagellum) and in intracellular vacuoles. Phosphatase reaction products were also observed in exocytosed membrane-bound material.

Trichomonas vaginalis: observation of coexistence of multiple viruses in the same isolate

Trichomonas vaginalis is a flagellated, parasitic protozoan that inhabits the urogenital tract of humans. Some isolates of T. vaginalis are infected with a double-stranded RNA (dsRNA) virus, which was described in the literature as homogeneous icosahedral viral particles with an isometric symmetry and 33 nm in diameter. This study examined in detail the viral particles in T. vaginalis isolate 347 and describes a heterogeneous population of viral particles. The different dsRNA viruses were only observed after a change in the technique. The sample was prepared by the negative staining carbon-film method directly onto freshly cleft mica. The detected viruses ranged in size from 33 to 200 nm. Among the shapes observed were filamentous, cylindrical, and spherical particles. These results show that T. vaginalis may be a reservoir for several different dsRNA viruses simultaneously.

Detection of Trichomonas vaginalis on modified Columbia agar in the routine laboratory

Broth culture of Trichomonas vaginalis is considered the "gold standard" for the diagnosis of trichomoniasis. Two studies were carried out to evaluate modified Columbia agar (MCA) for the isolation of T. vaginalis from clinical samples. Study I compared isolation on MCA to that on liquid medium with 889 vaginal samples. Out of 63 samples positive for T. vaginalis (7.1% of total), MCA identified 62 (98.4%) and broth identified 58 (92.1%). In study II, trichomoniasis was diagnosed within the scope of a screening program for a total of 39,585 men and women by culture on MCA and direct microscopy. Culture on MCA detected 199 (98.5%) and Gram staining detected 163 (80.7%) of 202 positive specimens. Wet-mount preparations used for symptomatic patients identified 103 (92.8%) of 111 cases. Culture of T. vaginalis from clinical samples on MCA is highly sensitive and reliable, as well as timesaving, and therefore suitable for screening of symptomatic and asymptomatic individuals.