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PubMed1985

Protective immunization against Treponema pallidum using specific immune complexes--an attempt.

Rabbits were immunized using isolated and dissolved specific immune complexes obtained from patients suffering from early syphilis. After immunization the rabbits were infected intradermally with living Treponema pallidum. Some of them did not develop lesions at the infection sites. In comparison to controls there was a delayed and reduced production of antibodies. The effect of immunization may be induced by a treponemal protein antigen as a constituent of the specific immune complexes.

Adult↗
PubMed2004

Borrelia burgdorferi persists in the brain in chronic lyme neuroborreliosis and may be associated with Alzheimer disease.

The cause, or causes, of the vast majority of Alzheimer's disease cases are unknown. A number of contributing factors have been postulated, including infection. It has long been known that the spirochete Treponema pallidum, which is the infective agent for syphilis, can in its late stages cause dementia, chronic inflammation, cortical atrophy and amyloid deposition. Spirochetes of unidentified types and strains have previously been observed in the blood, CSF and brain of 14 AD patients tested and absent in 13 controls. In three of these AD cases spirochetes were grown in a medium selective for Borrelia burgdorferi. In the present study, the phylogenetic analysis of these spirochetes was made. Positive identification of the agent as Borrelia burgdorferi sensu stricto was based on genetic and molecular analyses. Borrelia antigens and genes were co-localized with beta-amyloid deposits in these AD cases. The data indicate that Borrelia burgdorferi may persist in the brain and be associated with amyloid plaques in AD. They suggest that these spirochetes, perhaps in an analogous fashion to Treponema pallidum, may contribute to dementia, cortical atrophy and amyloid deposition. Further in vitro and in vivo studies may bring more insight into the potential role of spirochetes in AD.

Aged↗
PubMed1976

[Lysozyme content in the serum and organs of rabbits with a syphilitic infection].

The levels of lysozyme in the serum and organs of Shienshilla male rabbits infected with Nico-s treponema were determined. The studies showed that the lues infection affected the factors of non-specific immunity, which was evident from the changes in the lysozyme titer. Administration of benzylpenicillin resulted in a marked decrease in the lysozyme titer in all cases. The experiments are indicative of advisability of studying the use of crystalline lysozyme in combination with antibiotics for increasing the efficacy of therapy of syphilitic infection.

Animals↗
PubMed1984

Suppression of human lymphocyte responses by oral spirochetes: a monocyte-dependent phenomenon.

Spirochetes have been implicated in the pathogenesis of several human infections including syphilis, yaws, Lyme disease, and periodontal diseases. We examined soluble sonic extracts of oral spirochetes (Treponema denticola and T. vincentii) for their ability to alter human lymphocyte function. These organisms were isolated from subgingival plaque of patients with periodontitis. We found that sonicates of several but not all strains of T. denticola caused a dose-dependent inhibition of human lymphocyte responsiveness to Con A, PHA, PWM, and the recall antigen SKSD. Suppression involved alterations in DNA, RNA, and protein synthesis; there was no effect on cell viability. In contrast, sonicates of T. vincentii (medium-sized spirochetes) had no demonstrable effects on lymphocyte activation. The suppressive factor derived from T. denticola is heat-labile with a m.w. of approximately 100,000. To achieve maximal suppression, sonicates had to be added during the first 24 hr of incubation; there was no inhibition observed when added at 48 or 72 hr (along with 3H-TdR). Suppression was dependent on the presence of adherent monocytes; removal of these cells prevented spirochete-induced suppression of lymphocyte proliferation. Furthermore, the combination of indomethacin and catalase were able to reverse (or prevent) the inhibitory effects of the spirochete extracts, demonstrating a requirement for both prostaglandins and hydrogen peroxide. The potential role of such suppressive factors in periodontal disease is discussed.

Humans↗
PubMed2003

PCR-based identification of Treponema maltophilum, T amylovorum, T medium, and T lecithinolyticum in primary root canal infections.

OBJECTIVE: Molecular genetic methods have significantly contributed to the knowledge about the microbiota associated with infected root canals. Albeit spirochetes have been commonly observed in primary root canal infections, only recently they have been identified. The purpose of the present study was to investigate the occurrence of four treponemes-Treponema maltophilum, Treponema lecithinolyticum, Treponema amylovorum, and Treponema medium-in cases of primary endodontic infections associated with different forms of periradicular diseases through a 16S rDNA-based nested PCR assay. DESIGN: Samples were taken from thirty-one infected root canals associated with either asymptomatic or symptomatic apical periodontitis. DNA extracted from the samples was initially amplified using universal 16S rDNA primers, followed by a second round of amplification using the first PCR products to detect a specific fragment of the 16S rDNA of each target Treponema species. RESULTS: All cases were positive for the universal bacterial primers, indicating that samples contained bacterial DNA. Of the four target species, T. maltophilum was the most prevalent, being detected in 39% of the cases (33% of the asymptomatic cases and 50% of the symptomatic cases). T. lecithinolyticum was the next more prevalent among the species tested, being found in 26% of the samples (33% of asymptomatic cases and 10% of the symptomatic cases). T. amylovorum was found in 7% of the cases (5% of the asymptomatic cases and 10% of the symptomatic cases), while T. medium was in 13% of the cases (14% of the asymptomatic cases and 10% of the symptomatic cases). None of the species tested was significantly associated with clinical symptoms. CONCLUSIONS: This was possibly the hitherto first study to report the occurrence of T. lecithinolyticum, T. amylovorum, and T. medium in infections of endodontic origin. Overall, findings suggested that these oral treponemes, particularly T. maltophilum and T. lecithinolyticum, can be involved in the pathogenesis of periradicular diseases.

Adolescent↗
PubMed2001

Sample size calculations for clustered binary data.

In this paper we propose a sample size calculation method for testing on a binomial proportion when binary observations are dependent within clusters. In estimating the binomial proportion in clustered binary data, two weighting systems have been popular: equal weights to clusters and equal weights to units within clusters. When the number of units varies cluster by cluster, performance of these two weighting systems depends on the extent of correlation among units within each cluster. In addition to them, we will also use an optimal weighting method that minimizes the variance of the estimator. A sample size formula is derived for each of the estimators with different weighting schemes. We apply these methods to the sample size calculation for the sensitivity of a periodontal diagnostic test. Simulation studies are conducted to evaluate a finite sample performance of the three estimators. We also assess the influence of misspecified input parameter values on the calculated sample size. The optimal estimator requires equal or smaller sample sizes and is more robust to the misspecification of an input parameter than those assigning equal weights to units or clusters.

Bacteroides Infections↗
PubMed2000

Syphilis in women.

Infection with the spirochete Treponema pallidum causes syphilis. Transmission of syphilis occurs through sexual contact with persons who have infectious mucocutaneous lesions. Before the advent of penicillin, this infection was responsible for a large portion of the debilitated patients residing in mental institutions. Later during this century, the disease became somewhat uncommon, only to see a resurgence during the early part of this decade. Syphilis progresses through stages defined as primary, secondary, latent, and tertiary. Diagnosis of this infection is by clinical examination, dark-field microscopy, and serology. Penicillin is the treatment of choice for all stages of syphilis. Doxycycline and tetracycline are acceptable alternatives in some penicillin-allergic patients. If patients are pregnant or have central nervous system involvement, alternative regimens should not be used because of lack of efficacy and/or fetal toxicity. Therefore, these patients must be desensitized and treated with penicillin. No effective vaccine for this infection is currently available.

Journal Article↗
PubMed1989

Isolation of Fusobacterium nucleatum and electron microscopic observations of spirochetes from tropical skin ulcers in Papua New Guinea.

Tropical ulcer is a disabling condition of the lower leg affecting mainly young adults and older children. Microscopic observations of lesion material have shown fusiform bacilli and spirochetes. We used anaerobic culture techniques to isolate and identify these fusiform bacilli. Electron microscopic (EM) studies were performed to characterize the spirochetes. Material collected on swabs was used to inoculate pre-reduced media and to prepare smears for gram staining; the swabs were placed in fixative for EM study. After incubation, colonies containing fusiform bacilli were subcultured. The anaerobic gram-negative fusiform isolates were identified as Fusobacterium nucleatum using biochemical reactions, hemagglutination testing, and reaction of antigen preparations of the isolates and ATCC strains in serological tests with rabbit antisera. EM observations of negatively stained spirochetes revealed an 8-16-8 periplasmic flagellar arrangement. F. nucleatum and spirochetes may participate in the pathogenesis of this polymicrobic infection.

Adolescent↗
PubMed1991

[Benefit of the serological screening program for syphilis in pregnant women in Amsterdam in the period 1985-1989].

The results of the serological syphilis screening programme for pregnant women in the region of Amsterdam in the period 1985-1989 are described. In addition, a cost-benefit analysis was done to determine useful effects of the programme. Every GP and obstetrician routinely takes blood samples from pregnant women to determine the blood group, rhesus factor and syphilis serology. In the period 1985-1989, a total of 37,520 serum samples were screened for syphilis in the Amsterdam region by the Central Laboratory of the Blood Transfusion Service (until mid-1986) and by the Regional Public Health Laboratory of the Municipal Health Service (from mid-1986). In 55 women (0.15%) both the Treponema pallidum haemagglutination assay (TPHA) and the venereal disease research laboratory (VDRL) tests were positive. Further evaluation of these 55 women ultimately brought to light 10 women with positive syphilis serology who had not been treated and consequently might infect their child with Treponema pallidum. Considering the various transmission percentages of the bacterium from mother to foetus, which depend on the stage of the maternal infection, the screening programme has prevented two cases of congenital syphilis. This brings the cost-benefit ratio of the syphilis screening programme for the region of Amsterdam to 1:6.2. In view of these findings there is no reason to reconsider the current screening practice in Amsterdam.

Adult↗
PubMed1999

Lack of humoral immune protection against Treponema denticola virulence in a murine model.

This study investigated the characteristics of humoral immune responses to Treponema denticola following primary infection, reinfection, and active immunization, as well as immune protection in mice. Primary infection with T. denticola induced a significant (400-fold) serum immunoglobulin G (IgG) response compared to that in control uninfected mice. The IgG response to reinfection was 20, 000-fold higher than that for control mice and 10-fold higher than that for primary infection. Mice actively immunized with formalin-killed treponemes developed serum antibody levels seven- to eightfold greater than those in animals after primary infection. Nevertheless, mice with this acquired antibody following primary infection or active immunization demonstrated no significant alterations of lesion induction or decreased size of the abscesses following a challenge infection. Mice with primary infection developed increased levels of IgG3, IgG2b, and IgG2a antibodies, with IgG1 being lower than the other subclasses. Reinfected mice developed enhanced IgG2b, IgG2a, and IgG3 and less IgG1. In contrast, immunized mice developed higher IgG1 and lower IgG3 antibody responses to infection. These IgG subclass distributions indicate a stimulation of both Th1 and Th2 activities in development of the humoral immune response to infection and immunization. Our findings also demonstrated a broad antigen reactivity of the serum antibody, which was significantly increased with reinfection and active immunization. Furthermore, serum antibody was effective in vitro in immobilizing and clumping the bacteria but did not inhibit growth or passively prevent the treponemal infection. These observations suggest that humoral immune responses, as manifested by antibody levels, isotype, and antigenic specificity, were not capable of resolving a T. denticola infection.

Animals↗
PubMed1998

[The analysis of factors which affect qualification of pregnant women as cord blood donors].

Authors' analysis refers to reasons for which some women did not meet criteria for the programme of collection of cord blood by The Cord Blood Bank in Warsaw. The main reasons were: 1) reactivation of infection with CMV virus, 2) complications of delivery and 3) technical problems. We present also preliminary results of blood tests aimed at identification of some viral (hepatitis B and C, HIV, CMV), bacterial (Treponema pallidum) and protozoal infections (Toxoplasma) in the selected group of pregnant women.

Adult↗
PubMed1991

Application and evaluation of enzyme-linked immunosorbent assay and immunoblotting for detection of antibodies to Treponema hyodysenteriae in swine.

An enzyme-linked immunoassay (ELISA) has been developed to detect serum Immunoglobulin antibodies G and M to Treponema hyodysenteriae in vaccinated, experimentally infected and naturally infected swine. Naturally infected swine gave ELISA titres that were similar to experimentally infected swine, but were significantly less than the titres of vaccinated swine. When serum from naturally infected swine was used to probe nitrocellulose blots of sodium dodecyl sulphate-polyacrylamide gel electrophoresed whole cell proteins of T. hyodysenteriae, the immunoblotting patterns showed IgG antibodies were produced against many T. hyodysenteriae protein antigens and against lipopolysaccharide (LPS). The IgG antibodies directed against LPS were serotype-specific for that LPS and could be used to identify the serotype involved in the T. hyodysenteriae infection in that herd. IgM immunoblots also reacted with the many protein antigens but were less specific for LPS antigen, with a substantial degree of cross-reaction between the LPS of all serotypes. The data demonstrate that a microplate enzyme-linked immunosorbent assay, coupled with immunoblotting, is a very specific and sensitive test for detection of antibody to Treponema hyodysenteriae in swine.

Animals↗
PubMed1979

Isolation of pathogenic treponemes from hare.

A presumably new species of pathogenic treponemes was isolated from a lesion on the male organs of hare (Lepus sp.) and the scrotum of a rabbit (Oryctolagus sp.) was infected with this treponeme. Lesion developed on the scrotum after a 110-day incubation.

Animals↗
PubMed1965

INTERSPECIFIC TRANSFER OF THE "SEX-RATIO" AGENT OF DROSOPHILA WILLISTONI IN DROSOPHILA BIFASCIATA AND DROSOPHILA MELANOGASTER.

The maternally transmitted "sex-ratio" condition in several species of Drosophila appears to be due to infection by a microorganism of the genus Treponema. Drosophila bifasciata is an exception, since no microorganism has been found in the "sex-ratio" strains of this species. Normal D. bifasciata can be infected by injection of the hemolymph of a "sex-ratio" strain of D. willistoni containing treponemas. The progenies of the infected D. bifasciata, up to and including the F(4) and F(5) generations, have numerous treponemas in their hemolymph. Their progenies are, however, not unisexual, although both females and males are infected. The hemolymph of these D. bifasciata injected in D. melanogaster females causes typical "sex-ratio" symptoms in the progenies of the latter.

Animals↗