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Results for “TREPONEMA INFECTIONS”

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At least 235 records · Page 13Linked to original sources
PubMed1996

Hepatitis B virus markers among the prostitutes of Dhaka.

The objective of this study was to estimate the prevalence of hepatitis B virus (HBV) carrier states among prostitutes in Dhaka. Enzyme linked immunosorbent assay (ELISA) was used to detect HBV markers in a group of 164 prostitutes. Serological evidence of current or past HBV infection was present in 129(78.7%) prostitutes. HBsAg was detected in 16(9.7%) of whom 7(43.7%) were positive for e-antigen and e-antibody was present in another 7 (43.7%). Anti-HBs was detected in 94 (57.3%) of the specimens while anti-HBc in 108(73%) of HBsAg negative sera. Prevalence of HBV markers was 87% and 52.6% in VDRL reactive and non reactive sera respectively. The study indicates that the prevalence of HBV infection is high among the prostitutes in Dhaka city. Infection with Treponema pallidum is associated with increased risk of infection with HBV.

Bangladesh↗
PubMed2003

Effects of a mixed infection with Porphyromonas gingivalis and Treponema denticola on abscess formation and immune responses in mice.

Porphyromonas gingivalis and Treponema denticola have been found together in lesions of human periodontitis. We examined the ability of a mixed infection by both bacteria to synergistically form abscesses and disturb immune responses in mice. Absorbance of an invasive P. gingivalis 16-1 strain grown in tryptic soy broth and T. denticola ATCC 33520 strain grown in TYGVS medium were adjusted. BALB/c mice were injected with 200 microliters of the cell suspension at a site on the lateral dorsal area. The sizes of the subsequent subcutaneous abscesses were measured with a caliper gauge, and the area was expressed in square mm. Mixed infections by P. gingivalis and T.denticola produced larger abscesses than those formed after mono-infections by either P. gingivalis or T.denticola. The abscesses caused by mixed infection reached their maxima on the 6th day and maintained that size for the subsequent 5 days. The delayed type hypersensitivities against extracted antigens of P.gingivalis in mixed infection mice were significantly lower than those in the mono-infected mice. However, the IgG response to sonicated antigen of P.gingivalis did not differ between the two groups. The sizes of the abscesses caused by mixed infections in mice immunized with whole cells of P.gingivalis 16-1 were compared to those caused in sham-immunized mice. The average size of the abscess caused by mixed infection in immunized mice did not differ from that in sham-immunized mice, but many of the abscesses in immunized mice ruptured on the 4th or 5th day, followed by recovery in two weeks. These results suggest that mixed infection with P.gingivalis and T.denticola attenuates protective immune responses.

Abscess↗
PubMed1980

LSH hamster model of syphilitic infection.

The inbred LSH/Se LAK strain of hamster can be infected with Treponema pallidum Bosnia A, the causative agent of endemic syphilis. When infected, this strain consistently produced extensive chronic skin lesions that persisted for 6 to 9 months, even in the presence of peak antitreponemal antibody titers. The lymph nodes increased in weight and contained measurable numbers of treponemes. This infection also gave the hamster cross-immunity to T. pallidum Nichols and Treponema pertenue, the causative agents of venereal syphilis and frambesia, respectively. LSH hamsters are thus an excellent model to study the immune response mechanisms to syphilitic infection.

Animals↗
PubMed1980

Lack of serological evidence for venereal spirochaetosis in wild Victorian rabbits and the susceptibility of laboratory rabbits to Treponema paraluis-cuniculi.

Sera from 608 wild rabbits were examined using serological tests for syphilis as an indicator of infection with Treponema paraluis-cuniculi. Only eight sera gave positive or weakly positive results in the rapid plasma reagin (RPR) test, and none of these eight sera gave positive results in the Treponema pallidum haemagglutination assay (TPHA). Thus, it appears that wild rabbit populations in Victoria, Australia, are not naturally infected with T paraluis-cuniculi. Normal Australian laboratory rabbits however were readily infected with T paraluis-cuniculi, either by intradermal or intratesticular inoculation or by the venereal route. In the latter case, treponeme-containing lesions developed after about five months' cohabitation with infected mates. The disease was successfully transmitted from male to female and from female to male rabbits by the venereal route. In most cases infected rabbits became RPR-positive (17/19 rabbits) and in all cases TPHA-positive (19/19), indicating that serological tests for syphilis can be used to screen rabbits for this disease.

Animals↗
PubMed1979

Use of CB hamsters in the study of Treponema pertenue.

The CB/Ss LAK strain of inbred hamster was used as a model for studies of infection with Treponema pertenue and of acquired resistance to it. When infected, this strain developed cutaneous lesions which lasted for six to seven months, even in the presence of peak titres of antitreponemal antibody. The rate of appearance and resolution of these lesions varied with the size of the inoculum. The infected hamsters' inguinal lymph nodes increased significantly in weight and teemed with treponemes for several weeks. Animals infected for eight or 10 weeks obtained quick resolution of their lesions by treatment with penicillin and were thereafter resistant to reinfection.

Animals↗
PubMed1998

Virulence of a polymicrobic complex, Treponema denticola and Porphyromonas gingivalis, in a murine model.

The effect of a polymicrobic infection employing Treponema denticola and Porphyromonas gingivalis in the murine lesion model was used to determine the synergistic virulence of these two periodontopathic bacteria. At high doses of P. gingivalis W50, addition of T. denticola in the infection mixture had no effect on the formation and size of the spreading lesion caused by this microorganism. However, at low P. gingivalis challenge doses, T. denticola significantly enhanced the virulence of P. gingivalis compared with monoinfection of this microorganism. A potential role of the trypsin-like protease enzyme activity of P. gingivalis in this synergistic virulence was tested using P. gingivalis mutants deficient (i.e., BEI) or devoid (i.e., NG4B19) of this protease activity. These findings demonstrated that T. denticola-P. gingivalis complexes exhibit enhanced virulence in this model and that even using a polymicrobic challenge infection, the trypsin-like protease activity was important to P. gingivalis virulence expression.

Abscess↗
PubMed1979

Endemic syphilis: passive transfer of resistance with serum and cells in hamsters.

Serum or spleen cells from hamsters immune to infection with Treponema pallidum strain Bosnia A conferred partial protection against syphilitic infection by the same strain on recipient hamsters. Cutaneous lesions did not develop, and in the lymph nodes the average weight and number of treponemes detected were significantly lower than in normal and control hamsters. Treatment of the immune spleen cells with antithymocyte serum and complement abolished their ability to transfer resistance. This is the first direct evidence that thymus-derived cells are involved in resistance to syphilitic infection.

Animals↗
PubMed1994

Congenital and neonatal syphilis in guinea-pigs show a different pattern of immune response.

C4-deficient (C4D) and Albany strains of guinea-pigs transplacentally and neonatally infected with Treponema pallidum showed distinctive patterns of humoral immune responses. Congenitally infected progeny of both strains originated from dams intradermally (i.d.) infected at mid-pregnancy with virulent T. pallidum. In the neonatal groups families of C4D and Albany strains consisting of 1-3-day-old offspring and their mothers were i.d. infected with a similar dose of T. pallidum. Regardless of the strain, asymptomatic congenitally infected guinea-pigs (n = 16) responded from the first day of life with high levels of IgM [T. pallidum (TP) ELISA] antitreponemal antibodies and up to 85% presented with IgM CIC (circulating immune complexes) and IgM RF (rheumatoid factor). Although relatively high levels of IgM antitreponemal antibodies persisted in these animals throughout the 4-month experimental period, significant levels of host IgG antitreponemal antibodies were detectable after 2-3 months of age. Neonatally infected guinea-pigs of both strains (n = 27) responded similar to the infected sow but with relatively lower levels of IgM and IgG antitreponemal antibodies at 1 and 4 weeks, respectively, both of which increased with the time of infection. Antibodies were also detected in these animals by fluorescent treponemal antibody adsorption test (FTA-ABS). Unlike congenital syphilis, neonatally infected animals developed IgG-CIC after 2-3 months of infection and none of them showed any RF. In neonatal syphilis, FTA-ABS antibody levels were closely associated with the onset of lesions, whereas those of TP ELISA were not. The distinctive immune responses observed in these experimental models have the potential to differentiate between congenitally and neonatally infected human infants, even though the current clinical management is the same.

Animals↗
PubMed2003

Mixed infections with Porphyromonas gingivalis and Treponema denticola cause excessive inflammatory responses in a mouse pneumonia model compared with monoinfections.

Periodontopathic anaerobes such as Porphyromonas gingivalis are frequently found in aspiration pneumonia and lung abscesses. However, defense mechanisms and responses to these bacterial infections in the lung in vivo remain poorly understood. The coexistence of P. gingivalis with Treponema denticola has been found at higher levels and proportions in periodontally diseased sites. We hypothesized that mixed infections with P. gingivalis and T. denticola can cause severe respiratory disease. In the present study, inflammatory responses to mono- and mixed inoculations with P. gingivalis and T. denticola in the bronchoalveolar lavage (BAL) fluid were investigated. Acute pneumonia and lung abscesses in mice with the mixed infection resulted in a 40% mortality rate within 72 h, compared with only 10% mortality for the respective monoinfections. Pulmonary clearance of P. gingivalis was delayed in the mice with mixed infections with P. gingivalis and T. denticola. Tumor necrosis factor alpha (TNFalpha) interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) levels from BAL fluid of mice with mixed infections at 24 h after inoculation were significantly higher than those after P. gingivalis monoinfection (TNFalpha: P < 0.05, Il-1beta: P < 0.001, IL-6: P < 0.05). The chemokine KC level from BAL fluid of mice at 48 h (P < 0.05) and 72 h after mixed infection was also significantly increased when compared with that after P. gingivalis monoinfection (P < 0.001). The present study demonstrates that a mixed infection of P. gingivalis with T. denticola in mouse causes a marked bronchopneumonia and lung abscess in the mouse model.

Abscess↗
PubMed1982

Immune complexes in experimental T. pallidum infection in rabbits.

The polyethylene glycol precipitation method can be used to detect immune complexes in the sera of rabbits experimentally infected with Treponema pallidum. Immune complexes are present in the serum of rabbits infected either intravenously or intratesticularly and only when syphilitic lesions were present. Immune complexes were not observed in the serum of rabbits infected intradermally with T. pallidum.

Animals↗