[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.