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- Molecular Differentiation of Treponema pallidum Subspecies in Skin Ulceration Clinically Suspected as Yaws in Vanuatu Using Real-Time Multiplex PCR and Serological Methods. [JOURNAL ARTICLE]
- Am J Trop Med Hyg 2014 Nov 17.
We developed a TaqMan-based real-time quadriplex polymerase chain reaction (PCR) to simultaneously detect Treponema pallidum subspecies pallidum, T. pallidum subsp. pertenue, and T. pallidum subsp. endemicum, the causative agents of venereal syphilis, yaws, and bejel, respectively. The PCR assay was applied to samples from skin ulcerations of clinically presumptive yaws cases among children on Tanna Island, Vanuatu. Another real-time triplex PCR was used to screen for the point mutations in the 23S rRNA genes that have previously been associated with azithromycin resistance in T. pallidum subsp. pallidum strains. Seropositivity by the classical syphilis serological tests was 35.5% among children with skin ulcerations clinically suspected with yaws, whereas the presence of T. pallidum subsp. pertenue DNA was only found in lesions from 15.5% of children. No evidence of T. pallidum subsp. pertenue infection, by either PCR or serology was found in ∼59% of cases indicating alternative causes of yaws-like lesions in this endemic area.
- Characterization of Treponema denticola Mutants Defective in the Major Antigenic Proteins, Msp and TmpC. [JOURNAL ARTICLE]
- PLoS One 2014; 9(11):e113565.
Treponema denticola, a gram-negative and anaerobic spirochete, is associated with advancing severity of chronic periodontitis. In this study, we confirmed that two major antigenic proteinswere Msp and TmpC, and examined their physiological and pathological roles using gene-deletion mutants. Msp formed a large complex that localized to the outer membrane, while TmpC existed as a monomer and largely localized to the inner membrane. However, TmpC was also detected in the outer membrane fraction, but its cell-surface exposure was not detected. Msp defects increased cell-surface hydrophobicity and secretion of TNF-α from macrophage-like cells, whereas TmpC defects decreased autoagglutination and chymotrypsin-like protease activities. Both mutants adhered to gingival epithelial cells similarly to the wild-type and showed slightly decreased motility. In addition, in Msp-defective mutants, the TDE1072 protein, which is a major membrane protein, was abolished; therefore, phenotypic changes in the mutant can be, at least in part, attributed to the loss of the TDE1072 protein. Thus, the major antigenic proteins, Msp and TmpC, have significant and diverse impacts on the characteristics of T. denticola, especially cell surface properties.
- Periodontal and peri-implant microbiota in patients with healthy and inflamed periodontal and peri-implant tissues. [JOURNAL ARTICLE]
- Clin Oral Implants Res 2014 Nov 14.
To compare the prevalence and levels of six bacterial pathogens within the subgingival/submucosal microbiota at teeth versus implants with various clinical conditions.Twenty-two Chinese were included. Four subgingival/submucosal sites were selected for microbiological sampling within each subject, that is, (1) healthy peri-implant tissues; (2) peri-implantitis [PPD ≥ 5 mm, presence of bleeding on probing (BOP) and confirmed radiographic bone loss]; (3) healthy gingiva; and (4) periodontitis (PPD ≥4 mm). Subgingival/submucosal plaque was sampled using paper points. Quantitative real-time polymerase chain reaction (q-PCR) was used to quantify six pathogens, including Porphyromonas gingivalis (P.g.), Treponema denticola (T.d.), Aggregatibacter actinomycetemcomitans (A.a.), Fusobacterium nucleatum (F.n.), Prevotella intermedia (P.i.), and Staphylococcus aureus (S.a.). Counts were log10-transformed.The most commonly detected species were S. a. and F. n., while A. a. and. P. i. had the lowest detection frequency. The detection frequencies of diseased tooth or implant sites for each of the six target species were either equal to or higher than the respective frequencies at the corresponding healthy sites. There were no statistically significant differences for any of the species or clinical sites (P > 0.05, Cochran's Q test). No statistically significant differences in the bacterial loads were found among the four clinical sites; with the exception of F. nucleatum. This was more abundant in periodontitis sites (P = 0.023, Friedman's 2-way anova). Both periodontal and peri-implant sites, irrespective of their health status, were revealed to harbor S. aureus cells. The log10-transformed loads of S. aureus were approximately 3.5 within each of the clinical sites (P = 0.232). This was the highest of the six species analyzed.Within the same subjects, putative periodontal pathogens were common to both periodontal and peri-implant sites irrespective of health status. The prevalence and levels of P. gingivalis and F. nucleatum were significantly associated with periodontitis, but not with peri-implantitis. A. actinomycetemcomitans was associated with both disease conditions, periodontitis and peri-implantitis, but not with either gingival or mucosal health.
- Association between maternal periodontitis and preterm and/or low birth weight infants in normal pregnancies. [JOURNAL ARTICLE]
- J Matern Fetal Neonatal Med 2014 Nov 14.:1-20.
Abstract Objective: to relate the periodontal condition with the presence of periodontal bacteria in pregnant that had babies with preterm delivery or/and low weight at birth (PTLBW). Methods: We recruited 134 pregnant women without systemic diseases attending at the Gynaecology and Obstetrics Room, from Maternal Provincial Hospital, Córdoba, Argentine. Pregnant were grouped according to the International Classification for a System of Periodontal Disease. A sample from periodontal pocket was extracted to identify Porphyromonas gingivalis (Pg), Treponema denticola (Td), Tannerella forsythia (Tf) Prevotella intermedia (Pi) and Agreggatibacter actinomycemcomitans (Aa). Results: We identified 7 (5%) cases of children born underweight or preterm of mothers diagnosed with Gingivitis, 6 (4%) in Mild Periodontitis and 4 (3%) in Moderate Periodontitis. We estimated that when Pi and/or Aa were not detected in the periodontal pockets of mothers, the infants had a more than 129% chance of having normal birth weights (OR 3.47 for Pi and OR for Aa 2.29). The average age of the mothers who has PTLBW was 21 ± 3.5. The age showed an association with PTLBW (p <0.0008). Conclusions: The presences of periodontal pathogens in periodontal pockets from pregnant with different periodontal status, would associate with PTLBW infants when the mothers are young, and the normal term and normal birth weight infant it associated with the absence of periodonto bacteria like Pi y Aa.
- Predictors of lack of serological response to syphilis treatment in HIV-infected subjects. [Journal Article]
- J Int AIDS Soc 2014; 17(4 Suppl 3):19654.
The aim of this study was to determine factors associated with lack of serological response (LSR) to treatment of syphilis among HIV-infected subjects.Retrospective, longitudinal study on HIV-infected subjects diagnosed and treated for syphilis and with an assessable serological response between 1 January 2004 and 15 September 2013. LSR was defined as a <4-fold decline of rapid plasma reagin (RPR) titer or a failed reversion to nonreactive (if RPR ≤1:4 at diagnosis) after one year since treatment. Diagnoses of syphilis were staged in early syphilis (primary, secondary and early latent) or late syphilis (tertiary and late latent) according to clinical examination and patient's history. Syphilis was classified in new infections [NI: positive RPR and TPHA (Treponema pallidum Haemagglutination assay) titers in subjects without previous history of syphilis] or re-infections [ReI: a ≥4-fold increase of RPR titer in subjects previously successfully treated for syphilis]. Syphilis treatment was prescribed according to CDC guidelines. The crude incidence rates (IRs) of LSR were calculated per 1000-person months of follow-up (PMFU) as the total number of LSR episodes divided by the cumulative time contributed by all subjects (interval time since each syphilis diagnosis and the date of ascertainment of response). RESULTS are described as median (IQR) or frequency (%).565 diagnoses of syphilis with an assessable serological response in 421 patients; 458 (81%) were early syphilis, 189 (33%) were NI, 376 (67%) were ReI. At first, diagnosis of syphilis median age was 41 (36-47) years, 419 (99.5%) males, 391 (93%) MSM, HIV-infected since 7.7 (3.5-12.9) years, 75 (18%) HCV or HBV co-infected, 56 (13%) with a previous AIDS diagnosis, 82 (19%) antiretroviral treatment naïve, 102 (24%) with HIV-RNA ≥50 cp/mL, CD4+=576 (437-749) cells/mm(3), nadir CD4+=308 (194-406) cells/mm(3). LSRs were observed in 70/565 (12.4%) treated syphilis. Incidence of LSR decreased over time [2004-2008 IR=25.1 (17.2-33.1)/1000 PMFU; 2009-2010 IR=21.1 (12.3-29.9)/1000 PMFU; 2011-2013 IR=10.6 (5.1-18.2)/1000 PMFU; Poisson regression: p=0.001]. RESULTS of univariate and multivariate analysis on the risk of LSR are reported in Table 1.In HIV-infected subjects we observed 12% of LSR to treatment of syphilis. LSR was associated with an older age, late syphilis, lower nadir CD4+ and detectable HIV viral load.
- Prevalence of six periodontal pathogens in subgingival samples of Italian patients with chronic periodontitis. [Journal Article]
- New Microbiol 2014 Oct; 37(4):517-24.
The aim of this study was to investigate the subgingival prevalence of six periodontal pathogens in 352 Italian patients with chronic periodontitis. Possible correlations with clinical parameters, age, gender and smoking status were also investigated. At first visit a pooled subgingival plaque sample was obtained for each subject by using the paper-point method. The samples were processed and analysed according to a commercially available quantitative real time polymerase chain reaction assay (Meridol® Perio Diagnostics, GABA International, Switzerland). Porphyromonas gingivalis (Pg), Treponema denticola (Td), Tannerella forsythia (Tf), Prevotella intermedia (Pi), Fusobacterium nucleatum (Fn) and Aggregatibacter actinomycetemcomitans (Aa) were investigated. Fn resulted the most frequently detected (95%) while Tf showed the highest load (12x105 cells/plaque sample). Aa was the less represented bacteria for load and presence. Bacterial load of Pg, Td, Tf and Fn showed a direct correlation to Bleeding On Probing (BOP) and presence of suppuration (p=0.0001). The bacterial load was always directly correlated to Probing Pocket Depth (PPD) (p=0.0001). Among the investigated variables, PPD resulted the most important risk indicator for periodontal pathogens. BOP appeared as a risk indicator for Td, Tf, Pg detection. Few studies have described the microbiological pattern of chronic periodontal disease in the Italian population. Considering the different forms of periodontitis, similar investigations in other countries are needed to disclose any microbiological differences among populations, which may lead to more specific approaches to prevention and therapy.
- Occurrence of Socransky Red Complex in Pregnant Women With and Without Periodontal Disease. [JOURNAL ARTICLE]
- Oral Health Prev Dent 2014 Nov 7.
Purpose: To verify the presence of Socransky Red Complex (Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia) and P. intermedia using polymerase chain reaction (PCR) in periodontally healthy pregnant women and pregnant women with periodontal disease, as well as its relation to arterial blood pressure and capillary glycaemia. Materials and Methods: This case control study included 86 pregnant women, including 50 pregnant women with healthy periodontium, 27 with gingivitis and 9 with periodontitis. Arterial blood pressure and glycaemia were evaluated and recorded. Clinical specimens from the gingival crevice or periodontal pockets were gathered with sterile absorbent paper cones. DNA extraction was accomplished using the Easy-DNA Kit test and the presence of bacteria was detected by PCR with primers and specific probes for each microorganism. Results: The arterial pressure of all pregnant women was found to be within normal levels and 51% presented with hyperglycaemia, these two variables were not associated with periodontal conditions and/or presence of microorganisms. Socransky Red Complex was not present in pregnant women with healthy periodontium; however, it was present in pregnant women with gingivitis (3.7%) and in a higher percentage of pregnant women with periodontitis (33.3%). Conclusion: Socransky Red Complex was found only in cases of periodontal diseases and is not related to blood pressure and/or high levels of blood glucose.
- Evaluation of a Rapid Immunochromatographic Treponemal Antibody Test Comparing the Treponema Pallidum Particle Agglutination Assay. [JOURNAL ARTICLE]
- J Clin Lab Anal 2014 Nov 10.
In addition to conventional tests, several methods for detection of treponema-specific antibodies in clinical settings have been recently introduced. We aim to comparatively evaluate a rapid immunochromatographic test (ICT) for Treponema pallidum specific antibody (SD Bioline Syphilis 3.0) and the T. pallidum particle agglutination (TPPA) assay.In all, 132 serum samples from 78 syphilis patients and 54 syphilis-negative controls were analyzed. SD Bioline Syphilis 3.0 test (Standard Diagnostic, Inc., Yongin, Korea) was evaluated and compared to Serodia TPPA assay (Fujirebio, Inc., Tokyo, Japan). All discrepant results between the two assays were repeatedly tested and evaluated by the fluorescent treponemal antibody-absorption (FTA-ABS) assay. Test reproducibility and 95% limit of detection of SD Bioline Syphilis 3.0 were determined across three different lots for seven consecutive days in triplicate. Interference due to autoantibodies and pregnancy was also tested.Percent agreement between SD Bioline Syphilis 3.0 and TPPA assays was 99.2%. Sensitivity and specificity were 100%, respectively. In TPPA assay, test-to-test, day-to-day, and lot-to-lot variations were not identified until 1:320 titer (eightfold dilutions). There was no interference due to the presence of antinuclear antibodies or samples or pregnancy.Percent agreement of SD Syphilis 3.0 and TPPA was very good. Sensitivity and specificity were appropriate for T. pallidum antibody detection. Thus, a rapid ICT could be suitable for syphilis antibody detection.
- Sexually transmitted infections in adolescents: Maximizing opportunities for optimal care. [Journal Article]
- Paediatr Child Health 2014 Oct; 19(8):429-39.
Sexually transmitted infections are a growing public health concern in Canada, with rates of Chlamydia trachomatis infection, gonorrhea and syphilis increasing among adolescents and young adults. The present practice point outlines epidemiology, risk factors, laboratory testing and management for C trachomatis, Neisseria gonorrhoeae and Treponema pallidum, with a lesser focus on HIV. The need for test-of-cure and indications for further investigations are also discussed. The importance of maximizing opportunities to screen for and treat sexually transmitted infections in this age group is highlighted.
- Whole Genome Sequence of the Treponema pallidum subsp. endemicum Strain Bosnia A: The Genome Is Related to Yaws Treponemes but Contains Few Loci Similar to Syphilis Treponemes. [Journal Article]
- PLoS Negl Trop Dis 2014 Nov; 8(11):e3261.
T. pallidum subsp. endemicum (TEN) is the causative agent of bejel (also known as endemic syphilis). Clinical symptoms of syphilis and bejel are overlapping and the epidemiological context is important for correct diagnosis of both diseases. In contrast to syphilis, caused by T. pallidum subsp. pallidum (TPA), TEN infections are usually spread by direct contact or contaminated utensils rather than by sexual contact. Bejel is most often seen in western Africa and in the Middle East. The strain Bosnia A was isolated in 1950 in Bosnia, southern Europe.The complete genome of the Bosnia A strain was amplified and sequenced using the pooled segment genome sequencing (PSGS) method and a combination of three next-generation sequencing techniques (SOLiD, Roche 454, and Illumina). Using this approach, a total combined average genome coverage of 513× was achieved. The size of the Bosnia A genome was found to be 1,137,653 bp, i.e. 1.6-2.8 kbp shorter than any previously published genomes of uncultivable pathogenic treponemes. Conserved gene synteny was found in the Bosnia A genome compared to other sequenced syphilis and yaws treponemes. The TEN Bosnia A genome was distinct but very similar to the genome of yaws-causing T. pallidum subsp. pertenue (TPE) strains. Interestingly, the TEN Bosnia A genome was found to contain several sequences, which so far, have been uniquely identified only in syphilis treponemes.The genome of TEN Bosnia A contains several sequences thought to be unique to TPA strains; these sequences very likely represent remnants of recombination events during the evolution of TEN treponemes. This finding emphasizes a possible role of repeated horizontal gene transfer between treponemal subspecies in shaping the Bosnia A genome.