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Trichomonas vaginalis is a flagellated protozoan that causes trichomoniasis, a common nonviral sexually transmitted infection. T. vaginalis infection is asymptomatic in most infected men but can lead to chronic infection. The inflammatory response to chronic T. vaginalis infection may contribute to prostatic diseases, such as prostatitis and benign prostatic hyperplasia (BPH); however, studies on the relationship between T. vaginalis infection and prostate diseases are scarce. In this review, we discuss evidence from our studies on the involvement of T. vaginalis in the pathogenesis of prostate diseases, such as prostatitis and BPH. Studies of prostatitis have demonstrated that the attachment of T. vaginalis trophozoite to prostate epithelial cells (PECs) induces inflammatory cytokine production and inflammatory cell migration, leading to prostatitis. T. vaginalis also causes pathological changes, such as inflammatory cell infiltration, acinar changes, interstitial fibrosis, and mast cell infiltration, in prostate tissues of infected rats. Thus, T. vaginalis is considered an infectious agent that triggers prostatitis. Meanwhile, studies of prostatic hyperplasia revealed that mast cells activated by T. vaginalis-infected prostate cells secreted inflammatory mediators, such as β-hexosaminidase and tryptase, which promoted proliferation of prostate stromal cell (PSC). Moreover, interleukin-6 produced by proliferating PSCs induced the multiplication of BPH-1 epithelial cells as a result of stromal-epithelial interaction, suggesting that the proliferation of T. vaginalis-infected prostate cells can be induced through crosstalk with mast cells. These collective findings suggest that T. vaginalis contributes to the progression of prostatitis and prostatic hyperplasia by creating an inflammatory microenvironment involving PECs and PSCs.

Trichomonas vaginalis infection is one of the most prevalent sexually transmitted infections in humans and is now recognized as an important cause of infertility in men. There is little information about the effect of extracellular polymeric substances (EPS) from T. vaginalis on sperm, but previous reports do not provide a conclusive description of the functional integrity of the sperm. To investigate the impact of EPS on the fertilizing capacity of sperm, we assessed sperm motility, acrosomal status, hypo-osmotic swelling, and in vitrofertilization rate after incubating the sperm with EPS in vitrousing mice. The incubation of sperm with EPS significantly decreased sperm motility, viability, and functional integrity in a concentration and time-dependent manner. These effects on sperm quality also resulted in a decreased fertilization rate in vitro. This is the first report that demonstrates the direct negative impact of the EPS of T. vaginalis on the fertilization rate of sperm in vitro. However, further study should be performed using human sperm to determine if EPS has similar negative impact on human sperm fertilizing capacity in vitro.

Lactobacillus species in the female genital tract are thought to act as a barrier to infection. Several studies have demonstrated that lactobacilli can adhere to vaginal epithelial cells. However, little is known about how the adherence of lactobacilli to vaginal epithelial cells affects the acidity, cell viability, or proliferation of the lactobacilli themselves or those of vaginal epithelial cells. Lactobacillus acidophilus was co-cultured with immortalized human vaginal epithelial cells (MS74 cell line), and the growth of L. acidophilus and the acidity of the culture medium were measured. MS74 cell density and viability were also assessed by counting cell numbers and observing the cell attachment state. L. acidophilus showed exponential growth for the first 6 hr until 9 hr, and the pH was maintained close to 4.0-5.0 at 24 hr after culture, consistent with previous studies. The growth curve of L. acidophilus or the pH values were relatively unaffected by co-culture with MS74 cells, confirming that L. acidophilus maintains a low pH in the presence of MS74 cells. This co-culture model could therefore potentially be used to mimic vaginal conditions for future in vitro studies. On the other hand, MS74 cells co-cultured with L. acidophilus more firmly attached to the culture plate, and a higher number of cells were present compared to cells cultured in the absence of L. acidophilus. These results indicate that L. acidophilus increases MS74 cell proliferation and viability, suggesting that lactobacilli may contribute to the healthy environment for vaginal epithelial cells.

Feline intestinal tritrichomoniasis by Tritrichomonas foetus was first recognized in USA in 1999 and has so far been reported from UK, Norway, Switzerland, and Australia, but not from the Far East Asian countries. In November 2008, 2 female and male littermate Siamese cats, 6-month old, raised in a household in Korea were referred from a local veterinary clinic with a history of chronic persistent diarrhea. A direct smear examination of fecal specimens revealed numerous trichomonad trophozoites which were isolated by the fecal culture in InPouch TF-Feline medium. A PCR testing of the isolate based on the amplification of a conserved portion of the T. foetus internal transcribed spacer (ITS) regions (ITS1 and ITS2) and the 5.8S rRNA gene, and the molecular sequencing of the PCR amplicons confirmed infection with T. foetus. This is the first clinical case of feline intestinal trichomoniasis caused by T. foetus in Korea.

The flagellated protozoan Trichomonas vaginalis has been widely studied owing to its medical significance and unique structure. The complicated three-dimensional (3D) structure of the cellular components of T. vaginalis was reconstructed from serial sections to enable observation of the spatial features of the whole cell. Electron tomography was used to examine the detailed structure of the cellular organelles. Tomographic reconstruction showed the mastigont system and the parabasal filament of T. vaginalis in detail. The last thin filament (Pf3) was located close to the adjacent filament, and the two filaments appeared to be vertically parallel in the cross-sectional view. It is likely that Pf3 cannot be distinguished from the adjacent filament in 2D images obtained from transmission electron microscopy. Our 3D reconstruction of T. vaginalis revealed the presence of an additional striated fiber, and 3D reconstruction by electron tomography showed twisting of the split parabasal filament.

Our experiments aimed to clarify the mechanism by which host cell apoptosis is inhibited by infection with the intracellular protozoan parasite, Toxoplasma gondii (T. gondii). Mouse spleen cells were cultured in 6-well plates with RPMI 1640/ 10% FBS at 37?, in a 5% CO2 atmosphere. Apoptosis of spleen cells was induced by actinomycin-D (AD) treatment for 1 h prior to infection with T. gondii. A variety of assays were used to assess the progression of apoptosis: DNA size analysis on agarose gel electrophoresis, flow cytometry with annexin V/PI staining, and analysis of expression levels of Bcl-2 family and NF-kappaB mRNA and proteins by RT-PCR, Western blotting, and EMSA. Additionally, transmission electron microscopy (TEM) was performed to observe changes in cell morphology. Fragmentation of DNA was inhibited in spleen cells treated with AD and T. gondii 5 h and 18 h post infection, respectively, and flow cytometry studies showed a decreased apoptotic rates in AD and T. gondii treated spleen cells. We observed decreased expression of Bax mRNA and protein, while levels of Bcl-2 mRNA remained constant in spleen cells treated with AD and T. gondii. Caspase 3 and PARP were inactivated in cells treated with AD and T. gondii, and increased levels of cleaved caspase 8 were also observed. Analysis of EMSA and Western blot data suggests that activation of transcription factor NF-kappaB may be involved in the blockade of apoptosis by T. gondii. TEM analysis showed nuclear fragmentation and chromatin condensation occurring in spleen cells treated with AD; however, such apoptosis- associated morphological changes were not observed in cells treated with both AD and T. gondii tachyzoites. Together, these data show that T. gondii infection inhibits AD induced apoptosis via caspase inactivation and NF-kappaB activation in mouse spleen cells.

A total of 860 cellotape anal swab specimens from 326 school children of urban area, 243 of rura1 farm village and 291 of rural fishing village was submitted for Enterobius vermicularis egg detection from September through November 1985. Each specimen was collected in the morning. Among the total 860 children's submitting specimens, 316 (36.7 per cent) were positive for E. vermicularis eggs. Of the 326 children in the urban area, E. vermicularis eggs were detected in the 45 (13.8 per cent). This detection rate was lower significantly as compared with 143 (55.6 per cent) of 243 children in the farm village or 136 (46.7 per cent) of 291 children in the fishing village. The egg detection rate in the male children was lower remarkably than that in the female children.

The role of passive cell-mediated transfer of immunity against primary amoebic meningoencephalitis(PAME) in mice was studied. Naegleria fowleri, ITMAP 359, were cultured in CGVS medium. The ICR mice used were six week-old males of average weight of 15 g. Immunization was done by three intraperitoneal injections of l x 10(6) N. fowleri trophozoites at the interval of one week. Splenocytes were obtained from normal and immune mice spleens, and 1 x 10(7) cells were administered intraperitoneally into mice 3 days before challenge infection. Mice were infected intranasally with 7 x 10(4) N. fowleri trophozoites in a 3 microliter suspension under secobarbiturate anesthesia. Transplants of normal or immune splenocytes seem to alter the pattern of the PAME development. The splenocytes transferred from immune mice reduced the mortality rate in the N. fowleri infected mice, as compared with the mice transferred with the same number of normal splenocytes or without splenocyte. The blastogenic response of the splenocytes to both lipopolysaccharide and concanavalin A was elevated on day 7 after infection the mice transinoculated with immune splenocytes. The serum antibody titers in the mice transferred with immune splenocytes were increased gradually from day 7 up to day 20 after infections by mean of ELISA. It is suggested that the transfer of splenocytes from immunized mice conferred immunity against N. fowleri infection.

The 15th case of human thelaziasis is reported from Korea. The patient was a 15-year-old girl from Seoul. Both of the worms which were removed from her eye were female and were identified by the number of transverse cuticular striations (281, 172 and 162/mm in the oesophageal, middle and posterior portions, respectively), as Thelazia callipaeda. The patient owned a pet dog ADDITIONAL ABSTRACT: The 15-year-old patient had herself removed a worm from one eye. Two worms were identified morphologically as Thelazia callipaeda. The source of infection was uncertain, but the patient was known to have close contact with a dog. The authors refer to 14 previously reported cases of thelaziasis in Korea.

Present study was undertaken to elucidate the changes of the ultrastructure of Naegleria fowleri trophozoite in brain tissue of mice and culture medium. Naegleria fowleri, 0359 strain, which used in this study was cultured in axenic liquid medium, CGVS medium. Each mouse was inoculated with 1 x 10(5) amoebas intranasally under secobarbital anesthesia, and sacrificed on 7th day after the infection. Comparative observation of the ultrastructure of the amoebas in axenic culture and experimentally infected mice brain was done with transmission electron microscope. The results are summarized as follows: 1. The amoebas in mouse brain tissue were round in outline, whereas those of amoebas from axenic culture showed irregular appearance. 2. Mitochondria in the amoebas from axenic culture was oval, round and cylindrical shape and darkly stained, whereas those of the amoebas from mouse brain tissue showed dumbbell shape together with above forms. The stain was not unique, but light and/or dark. 3. Rough endoplasmic reticulum of amoebas in brain tissue was tubular, but from culture it was vesicular or tubular in shape. 4. Empty vacuoles were demonstrated in amoebas from culture, while food vacuoles with myelinated structures were abundant in those from tissue, suggesting a strong phagocytic activity. 5. Mouse brain tissue infected were extensively destroyed, and polymorphonuclear leukocytes were infiltrated predominantly with inflammatory lesion. Amoebas were observed in the vicinity of the capillary.

This study was to observe the changes of blastogenic responses of splenic lymphocytes to T-cell mitogens, N. fowleri lysate and concanavalin A, and serum antibody titer during the course of experimental PAM in mice. Naegleria fowleri, strain 0359, was cultured in the CGVS medium axenically and inoculated intranasally with 7 x 10(4) trophozoites for the development of experimental PAM in mice. The amoebae were subjected to ultrasonication and centrifuged at 20,000 g for 60 minutes, and filtered through 0.2 micro-m filter membrane. The supernatant, N. fowleri lysate, was used as T-cell mitogen, and antigen for ELISA. The serum antibody was examined by ELISA using peroxidase conjugate. Two hundred micro-l of 10(6) splenocytes in RPMI 1640 containing 10% fetal calf serum were added to each well of a microtiter plate. To each well was added T-cell mitogens, 100 micro-g/ml of N. fowleri lysate or 4 micro-g/ml of con. A, and the plates were incubated for 42 hours at 37 C in 5% CO(2) incubator. Cultures were pulsed with 1 micro-Ci of methyl-(3H)-thymidine 6 hour before harvesting. The mean blastogenic response of the splenocytes to N. fowleri lysate was reduced, whereas that to con. A was also reduced up to on day 11 after infection. Both of these results were statistically significant compared with those of uninfected control group. The serum antibody titers were increased gradually up to day 15. The results indicated that there was an impairment of the blastogenic response of splenocytes to N. fowleri lysate during the acute course of experimental PAM in mice.

A comparison was made of a new serological method, thin layer immunoassay (TIA), and an established method, enzyme-linked immunosorbent assay (ELISA), in the detection and quantification of antibodies in clonorchiasis. Saline extract of lyophilized Clonorchis sinensis adult worm was used as antigen, and TIA by the method of Elwing et al. (1976) and ELISA by Voller et al. (1974) were performed. Using sera from known clonorchiasis cases, 100 % of the sera tested were positive by TIA and 88.3 % by ELISA. TIA produced false positive results in 14 out of 36 cases, which were 10 amoebiasis cases, 16 paragonimiasis cases and 10 healthy controls. ELISA, however, produced a small number of false positives, 7 out of 55 cases. There was correlation between immunoglobulin G level in sera and ELISA value (correlation coefficient, 0.69), whereas no correlation between immunoglobulin G level and TIA result. The performance of TIA and ELISA was not correlated in the results using homologous antigen.

In order to test the function of lymphocytes in Naegleria fowleri-infected mice, the in vitro blastogenic response of splenocyte cultures to non-specific mitogens was studied. Concanavalin A and lipopolysaccharide stimulation were used as tests of T cell and B cell function. For the first 14 days following N. fowleri infection, lymphoblastic transformation induced by T-cell mitogen was markedly reduced in comparison to the uninfected control mice. The blastogenic response to B-cell mitogen remained depressed in the infected mice up to 14 days after infection. The fluorescent antibody titers of sera of N. fowleri infected mice were between 1:4 and 1:32. The results suggest that there is a suppression of cell mediated immunity during the acute course of experimental Naegleria meningoencephalitis in mice.