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- Periodontal bacteria in human carotid atherothrombosis as a potential trigger for neutrophil activation. [JOURNAL ARTICLE]
- Atherosclerosis 2014 Aug 11; 236(2):448-455.
Epidemiological, biological and clinical links between periodontal and cardiovascular diseases are now well established. Several human studies have detected bacterial DNA corresponding to periodontal pathogens in cardiovascular samples. Intraplaque hemorrhage has been associated with a higher risk of atherosclerotic plaque rupture, potentially mediated by neutrophil activation. In this study, we hypothesized that plaque composition may be related to periodontal pathogens.Carotid culprit plaque samples were collected from 157 patients. Macroscopic characterization was performed at the time of collection: presence of blood, lipid core, calcification and fibrosis. Markers of neutrophil activation released by carotid samples were quantified (myeloperoxidase or MPO, cell-free DNA and DNA-MPO complexes). PCR analysis using specific primers for Porphyromonas gingivalis, Aggregatibacter actinomycetemcommitans, Treponema denticola, Prevotella intermedia and Tannerella forsythia was used to detect DNA from periodontal pathogens in carotid tissues. In addition, bacterial lipopolysaccharide (LPS) and Immunoglobulins G against T. forsythia were quantified in atherosclerotic carotid conditioned medium.Intraplaque hemorrhage was present in 73/157 carotid samples and was associated with neutrophil activation, reflected by the release of MPO, cell-free DNA and MPO-DNA complexes. LPS levels were also linked to intraplaque hemorrhage but not with the neutrophil activation markers. Seventy-three percent of the carotid samples were positive for periodontal bacterial DNA. Furthermore, hemoglobin levels were associated with the detection of T. forsythia and neutrophil activation/inflammation markers.This study suggests a potential role of periodontal microorganisms, especially T. forsythia, in neutrophil activation within hemorrhagic atherosclerotic carotid plaques.
- Dot blot assay of antibodies to Treponema pallidum. [Journal Article]
- Dokl Biochem Biophys 2014 Jul; 457(1):149-51.
- Comparative genome analysis and identification of competitive and cooperative interactions in a polymicrobial disease. [JOURNAL ARTICLE]
- ISME J 2014 Aug 29.
Polymicrobial diseases are caused by combinations of multiple bacteria, which can lead to not only mild but also life-threatening illnesses. Periodontitis represents a polymicrobial disease; Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia, called 'the red complex', have been recognized as the causative agents of periodontitis. Although molecular interactions among the three species could be responsible for progression of periodontitis, the relevant genetic mechanisms are unknown. In this study, we uncovered novel interactions in comparative genome analysis among the red complex species. Clustered regularly interspaced short palindromic repeats (CRISPRs) of T. forsythia might attack the restriction modification system of P. gingivalis, and possibly work as a defense system against DNA invasion from P. gingivalis. On the other hand, gene deficiencies were mutually compensated in metabolic pathways when the genes of all the three species were taken into account, suggesting that there are cooperative relationships among the three species. This notion was supported by the observation that each of the three species had its own virulence factors, which might facilitate persistence and manifestations of virulence of the three species. Here, we propose new mechanisms of bacterial symbiosis in periodontitis; these mechanisms consist of competitive and cooperative interactions. Our results might shed light on the pathogenesis of periodontitis and of other polymicrobial diseases.The ISME Journal advance online publication, 29 August 2014; doi:10.1038/ismej.2014.155.
- Neurosyphilis in a man with human immunodeficiency virus. [Journal Article]
- J Clin Aesthet Dermatol 2014 Aug; 7(8):35-40.
The authors describe a 33-year-old man with human immunodeficiency virus who developed erythematous macules on the palms and soles with subsequent headaches, papilledema, and iritis. They review the salient characteristics of neurosyphilis with a focus on human immunodeficiency virus-positive individuals. The incidence of syphilis has increased since the year 2000 in African Americans, Hispanics, and men who have sex with men. Treponema pallidum is the causative agent of this disease-a fastidious, slowly growing, microaerophilic spirochete. Sexual contact is the most common mode of transmission. The rapid plasma reagin, Venereal Disease Research Laboratory assay, and fluorescent treponemal antibody absorption assay are commonly used to diagnose syphilis. The mainstay treatment is penicillin. Special considerations exist in the natural history and management of syphilis in the setting of human immunodeficiency virus.
- Treponema pallidum hemagglutination assay seroreactivity among healthy Indian donors and its association with other transfusion transmitted diseases. [Journal Article]
- Asian J Transfus Sci 2014 Jul; 8(2):109-12.
The aim of the present study was to determine the prevalence of syphilis infection by Treponema pallidum hemagglutination assay (TPHA) among blood donors in Delhi and to study their correlation with other markers of transfusion transmitted infections such as hepatitis C virus (HCV), human immunodeficiency virus (HIV) and hepatitis B surface antigen (HBsAg) so as to establish the utility of TPHA over and above venereal diseases research laboratory test (VDRL), not only as a marker for testing T. pallidum infection, but also as a marker of high risk behavior.This prospective study was carried out in the Regional Blood Transfusion Centre, Lady Hardinge Medical College and associated Sucheta Kriplani Hospital, New Delhi for a period of 2 years. Donated blood was screened for TPHA seroreactivity along with screening for anti HIV I and II, anti-HCV, HBsAg by third generation enzyme-linked immunosorbent assay test. A total of 8082 serum samples of blood donors were collected from healthy blood donors in our blood bank. They were classified into two groups- test group and control group based on TPHA positivity. The co-occurrence of HBsAg, HIV and HCV infection were determined in TPHA positive blood donors (test group) in comparison with TPHA negative blood donors (control group).We found the TPHA seroreactivity to be 4.4% in Delhi's blood donors. Nearly 8.2% (663/8082) of the donated blood had serological evidence of infection by at least one pathogen (syphilis/HIV/hepatitis B virus/HCV) and 6.63% (44/663) donors with positive serology had multiple infections (two or more). Quadruple infection was seen in one donor, triple infection was seen in three donors and double infection was seen in 40 donors. Prevalence of HIV seroreactivity was found to be statistically significant and HCV seroreactivity statistically insignificant in TPHA positive group in comparison to TPHA negative group.In our study, the TPHA seropositivity correlated with higher HIV and HCV seropositivity and the same correlation has been observed by several other studies also. In view of these observations, we propose that testing for syphilis by more sensitive and specific treponemal markers like TPHA rather than VDRL, rapid plasma reagin tests; as TPHA also has the added advantage of picking up all the high risk donors, whereas, VDRL picks up only currently infected donors. Moreover, TPHA should be continued as a marker of high risk behavior especially in high prevalence areas like India where we don't have universal access to markers like nucleic acid amplification technique.
- Pilot study on the clinical and microbiological effect of subgingival glycine powder air polishing using a cannula-like jet. [JOURNAL ARTICLE]
- Int J Dent Hyg 2014 Aug 26.
To assess the efficacy of subgingival glycine powder air polishing (GPAP) during supportive periodontal therapy (SPT).Each quadrant of 25 subjects was randomly assigned to the following treatments: subgingival scaling with hand instruments (SRP), GPAP, subgingival ultrasonic debridement (UD) and no subgingival treatment (NT). Clinical recordings included the following: probing pocket depth (PPD), gingival recession (RE), clinical attachment level (CAL), Gingival and Plaque Index. Subgingival plaque samples were taken from two sites >4 mm per quadrant. Therapy, recordings and microbial sampling were performed at baseline, 3 and 6 months, while at 1 month only clinical recordings and sampling were performed. Subgingival samples were analysed using 'checkerboard' DNA-DNA hybridization for Porphyromonas gingivalis, Tannerrella forsythia and Treponema denticola.All groups were homogeneous at baseline for the clinical parameters assessed. The GPAP group displayed statistically significant higher PPD compared to SRP and UD at 1, 3 and 6 months and no statistical differences with the 'no treatment' group at all time points. At 1 month, the GPAP group displayed statistically significantly higher levels of CAL compared to SRP, while at 3 and 6 months statistically significant differences were observed with groups assigned to SRP and UD. No differences were observed among groups for RE, PI, GI and numbers of the investigated bacteria at any time point.On the basis of clinical and microbiological data, this study does not support the superiority of GPAP as sole treatment over SRP or subgingival ultrasonic scaling.
- Dentilisin involvement in coaggregation between Treponema denticola and Tannerella forsythia. [JOURNAL ARTICLE]
- Anaerobe 2014 Aug 21.
Periodontitis arises from a biofilm consisting of gram-negative anaerobic rods and spirochetes. Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia, termed the Red complex, have been co-isolated with high frequency from chronic periodontitis lesions, and these microorganisms are thought to be major pathogens of the disease. Coaggregation is an important strategy in the colonization of dental plaque biofilm by these bacteria. In the present study, we investigated the coaggregation of T. denticola strains with T. forsythia ATCC 43037 by use of visual grading or spectrophotometry. T. denticola ATCC 35405 coaggregated with T. forsythia, reaching a plateau at approximately 60 min. This coaggregation was inhibited by heat treatment of T. denticola ATCC 35405, but not of T. forsythia. Disaccharides such as sucrose, maltose, and lactose inhibited coaggregation by approximately 50%. The coaggregation reaction varied among T. denticola strains. There was somewhat less coaggregation between T. denticola ATCC 33520 and T. forsythia than between T. denticola ATCC 35405 and T. forsythia, although this difference was not statistically significant; T. denticola ATCC33521 showed a trace level of coaggregation with T. forsythia. The magnitude of coaggregation among the three T. denticola strains was proportional to their dentilisin activities. Inactivation of dentilisin abolished coaggregation activity, but inactivation of the major outer sheath protein did not. In addition, phenylmethylsulfonyl fluoride did not affect coaggregation. These results indicate that dentilisin is involved indirectly in the coaggregation between T. denticola and T. forsythia, because its proteolytic activity is not required, possibly via ligand maturation.
- Quantification of Periodontal Pathogens Cell Counts by Capillary Electrophoresis. [JOURNAL ARTICLE]
- J Chromatogr A 2014 Aug 7.
Gingivitis is a highly prevalent periodontal disease around the worldwide. Porphyromonas gingivalis (P.g), Treponema denticola (T.d) and Tannerela forsythia (T.f) were considered to be three important periodontal pathogens related to gingivitis, and research shows that the counts of periodontal pathogen cells in the patients before, during, and after fixed orthodontic appliance therapy were quite different. We proposed a simple method to extract the periodontal pathogens from the periodontal pocket in this work and demonstrated a new approach to determine periodontal pathogen level based on capillary electrophoresis (CE). After polymerase chain reaction amplification of P.g (197bp), T.d (311bp), and T.f (641bp), it shows that they can rapidly identified by CE within 5min. The peak area in the eletropherogram is linearly related to the concentration of P.g, T.d, and T.f, and the correlation coefficients R(2) corresponding to them are 0.993, 0.993, and 0.956, respectively. According to this linearly relationship, the estimated concentration of P.g, T.d, and T.f in gingival crevicular fluid from one volunteer was inferred to be about 9.90×10(2), 1.48×10(3), and 9.01×10(2)cells/μl, respectively.
- Neurosyphilis in the mixed urban-rural community of the Netherlands. [Journal Article]
- Acta Neuropsychiatr 2014 Jun; 26(3):186-92.
Neurosyphilis is caused by dissemination into the central nervous system of Treponema pallidum. Although the incidence of syphilis in the Netherlands has declined since the mid-1980s, syphilis has re-emerged, mainly in the urban centres. It is not known whether this also holds true for neurosyphilis.The epidemiology of neurosyphilis in Dutch general hospitals in the period 1999-2010 was studied in a retrospective cohort study. Data from the Dutch sexually transmitted infection (STI) clinics were used to analyse the number of patients diagnosed with syphilis in this period.An incidence of neurosyphilis of 0.47 per 100 000 adults was calculated, corresponding with about 60 new cases per year. This incidence was higher in the western (urbanised) part of the Netherlands, as compared with the more rural areas (0.6 and 0.4, respectively). The number of patients diagnosed with syphilis in STI clinics increased from 150 to 700 cases in 2004 and decreased to 500 new cases in 2010. The sex ratio was in favour of men, yielding a percentage of 90% of the syphilis cases and of 75% of the neurosyphilitic cases. The incidence of neurosyphilis was highest in men aged 35-65 years, and in women aged 75 years and above. The most frequently reported clinical manifestation of neurosyphilis was tabes dorsalis. In this study, 15% of the patients were HIV seropositive.The incidence of neurosyphilis in a mixed urban-rural community such as the Netherlands is comparable to that in other European countries. Most patients are young, urban and men, and given the frequent atypical manifestations of the disease reintroduction of screening for neurosyphilis has to be considered.
- Surveillance study of Treponema pallidum harbouring tetracycline resistance mutations in patients with syphilis. [LETTER]
- Int J Antimicrob Agents 2014 Jul 23.