الفهرس 
Trichomonas tenaxOnly 14 pages are availabe for public view
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Abstract
T.tenax is an anaerobic widespread flagellated protozoan that inhabits the human oral cavity and is more frequently found among people with poor oral hygiene, especially those with advanced periodontal diseases. It has a worldwide prevalence in the mouth ranging from 4 to 53%.
The role of this species as a pathogen had been clearly implicated in various pathological processes that arise both within and outside the boundaries of the mouth. Although a relationship between the increased occurrence of this protozoan and progression of periodontal disease has been demonstrated, the precise mechanism of tissue damage is still unknown. Further studies are necessary for determining the real nature of the relationship between this species and periodontal diseases.
The aim of the present study was to estimate the occurrence of T.tenax in individuals having oral infections in comparison with healthy control and to investigate the possible relationship between pathogenicity of T.tenax in periodontal infections and its proteolytic activity.
The study included 100 subjects of both sexes, who attended the out–patients’ clinics at the faculty of Dentistry, Ain Shams University, at time interval from May 2010 to January 2011. Their age ranged from 10-65 years. Detailed history was taken from each individual.
Individuals enrolled in the present study were divided into 2 groups.
Group I: (Patients group/G1): Included 70 patients who were complaining of oral infection as periodontitis and/ or gingivitis.
Group II: (Control group/G2): Included 30 healthy subjects who were not complaining of any oral infections, diabetes, hypertension or chronic septic foci and had not been taking any immunosuppressive therapy or antibiotics for the last three months.
Plaques and or calculi samples were collected from individuals in G1 and saliva samples were collected from individuals in G2, and then subjected to: 1) parasitological examination direct wet smear using saline; modified Glycerol jelly (MGJ) direct smear using iodine, eosine and methylene blue; 2) Culture on TYI-S-33 medium. Isolates successfully maintained in culture, were used for preparation of T.tenax cell lysates which further subjected to: 1) Analysis of protein profile by SDS-PAGE under reducing conditions, 2) Analysis of proteases by non-denaturing gelatin-SDS-PAGE.
Results of the present study showed the following:
Regarding the patients group, 22.9% of individuals were positive for T.tenax, 2.8% for E.gingivalis, 5.7% for both T.tenax and E.gingivalis. The total frequency of oral trichomoniasis was 28.6%, while that of E.gingivalis was 8.6%. While, in the control group (G2), all the saliva samples collected were negative for both T.tenax and E.gingivalis by both wet mount and culture.
Males infected with T.tenax were more than females (60% versus 40%). The mean age among T.tenax infected patients was 37.85, and the highest overall frequency was in the age group 41-50 years (35%), followed by the age group 21-30 years (25%), and equal in age group 11-20 years and 31-40 years (15%). The age group >50 years had the lowest frequency (10%).
Infection with T.tenax was found to be related to periodontal tissue inflammation, as 40% of T.tenax infected patients were suffering from severe gingivitis, 30% were suffering from moderate gingivitis, and 25% had both gingivitis and periodontitis, while only 5% had mild gingivitis.Meanwhile, it was not found in patients with good oral conditions.
Concerning risk factors associated with periodontal infections in the T.tenax positive patients; 45% were smokers, 15% diabetics, 5% hypertensive, 0% COPD, while 80% were free from any systemic diseases. There was an association between dirty oral cavity and occurrence of T.tenax infection, as 100% of T.tenax positive patients had dirty oral cavity and 10% used tooth paste and brush once per day, while 90% sometimes.
Frequency of T.tenax was found to be closely associated with the presence of heavy layer of dental calculi and plaques as 10% of infected patients had dental calculi, 30% had dental plaques, and 60% had both dental plaques and calculi.
Modified TYI-S-33 medium was found to be superior to the wet smear method in detecting T.tenax, as culture was able to detect 100% of the positive samples, while wet smear was able to detect 55% of the positive samples. No positive cases by wet mount examination gave negative result when cultured on TYI-S-33 medium. The sensitivity and specificity of wet mount microscopic examination was 55% and 100% respectively, with Positive Predictive Value (PPV) 100%, Negative Predictive Value (NPV) 84.74%, and diagnostic Accuracy 87.14%.
Several isolates cultivation on TYI-S-33 medium produced heavy populations upon transfer, while other isolates died out after several subcultures, so only seven isolates out of twenty were successfully maintained in culture.
Comparison of growth kinetics of the seven T.tenax isolates showed a wide variability in the growth characteristics in terms of the length of log phase, growth peaks reached, generation times, division rate and number of divisions.
The protein profile of the seven T.tenax isolates were compared using SDS-PAGE analysis and the result showed that protein profiles of the seven T.tenax isolates revealed a total 53 bands ranged in molecular weight from 5 - 95 kDa using 12% resolution gel. 19 bands ranging from 10 to 64 kDa (64, 56, 52, 46, 45, 44, 43, 40, 39, 37, 30, 29, 28, 27, 26, 25, 24, 17, and 10) were common among several isolate of T.tenax, while most of the bands were characteristic to a specific isolate suggesting the existence of different strains with possibility of variable pathogenic potentials.
T.tenax isolates from different patients were found to possess several proteinase bands by non-denaturing gelatin-SDS-PAGE using 12% resolution gel co-polymerized with 0.1% gelatin.A total of 19 bands ranged in molecular weight from 14 - 66 kDa were obtained.Most of the bands were characteristic to a specific isolate, while some were common among several isolate suggesting the complexity and heterogeneity of the proteinases in this protozoan.
The proteinases bands were intensified by a cysteine proteinase activator as di-thiothreitol (DTT), and totally disappeared by treatment with cysteine proteinase inhibitor (E-64) suggesting that the proteinases were of cysteine proteinases type.