Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “TREPONEMA INFECTIONS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources
PubMed1955

Njovera.

Explore the source record for details and available documents.

Humans↗
PubMed1980

Abrogation of genetically controlled resistance of mice to Treponema pallidum by irradiation.

Infection with Treponema pallidum, the causative agent of human syphilis, gives rise to a complex immune response involving both humoral and cellular components. The exact nature of this response and how it relates to the disease process is a matter of considerable speculation. In recent years, studies have been directed towards defining the role of cell-mediated immunity (CMI) in syphilis. These have been conducted mainly in vitro because the general unavailability of inbred rabbits, the principal animals for experimental syphilis research, has limited the application of in vivo procedures. A prime deterrent to using mice for the study of syphilis has been their failure to exhibit pathology, even in the face of a persistent infection. We report here that on intradermal (i.d.) infection, transient primary lesions, characteristic of those seen in naturally acquired human syphilis, can be produced regularly in some strains of mice but not others, indicating a genetic basis for host susceptibility. Strains of mice which normally fail to develop lesions, do so after exposure to ionising radiation. Evidence is presented for a multiple role of the immune response during local infection.

Animals↗
PubMed1977

In vitro cell response of Treponema pallidum-infected rabbits. III. Impairment in production of lymphocyte mitogenic factor.

Production of mitogenic factor was examined in rabbits infected intratesticularly with T. pallidum and in control animals injected with saline or saline extract of normal rabbits' testes. Lymph nodes and spleen from animals killed 2, 6 and 12 weeks after injection were used as the source of lymphocytes, cultured in serum-free medium in the presence of Reiter antigen. The active supernatants of lymph node cells (LNAS) and spleen cells (SPAS) were examined for the presence of mitogenic factor using normal rabbit peripheral lymphocytes. The LNAS of control animals showed a mitogenic index (MI) between 4 and 6 and the infected animals less than 2. The SPAS of infected and control rabbits showed an MI of less than 2. The lower mitogenicity in LNAS of infected and that of SPAS of infected and control animals seems to be due to the presence of inhibitors of DNA synthesis.

Animals↗
PubMed1977

In vitro cell response of Treponema pallidum-infected rabbits. II. Inhibition of lymphocyte response to phytohaemagglutinin by serum of T. pallidum-infected rabbits.

Serum inhibitors of lymphocyte response to PHA were found in T. pallidum-infected rabbits. The humoral inhibitors could be detected as early as 10 days after infection and persisted for at least 6 months. The factors also suppressed the allogeneic lymphocyte response. Control, or normal, rabbit sera likewise contain serum inhibitors, but in much lower concentration. The detection of the humoral inhibitors depended on the susceptibility of the indicator lymphocytes. Cells of some rabbits were more sensitive to the inhibitors than others. In addition to serum inhibitors, lymphocytes of T. pallidum-infected animals seem to be impaired and responded to PHA less vigorously than cells of normal rabbits. The inhibitory activity is most likely the result of a complex group of substances with different physicochemical characteristics; some pre-exist and others are newly formed after infection. Problems associated with the detection of such inhibitors are discussed.

Animals↗
PubMed1983

Treponema paraluis-cuniculi infection in a commercial rabbitry: epidemiology and serodiagnosis.

The epidemiology of Treponema paraluis-cuniculi infection in a commercial rabbit breeding facility was described using several serologic tests. The Venereal Disease Research Laboratory, rapid plasma reagin, microhemagglutination and fluorescent treponemal antibody-absorption tests were used to detect antibodies to T paraluis-cuniculi. Young adult New Zealand white rabbits, tested prior to entry into the breeding program, were nearly always free of T paraluis-cuniculi infection. In adult females, the prevalence of T paraluis-cuniculi infection increased with parity; females para 6 or greater were usually seropositive. Most adult males seroconverted within 6 months of entering the breeding program; all males were seropositive after 12 months in the breeding program. This suggested that T paraluis-cuniculi spreads mainly by horizontal transmission during breeding in adult rabbits. Of the two nontreponemal antigen tests used, the Venereal Disease Research Laboratory test was more sensitive, whereas the rapid plasma reagin test was more specific in detecting T paraluis-cuniculi infection; the fluorescent treponemal antibody-absorption test was used as the confirmatory treponemal antigen test. However, neither nontreponemal antigen test was completely satisfactory. On the other hand, the sensitivity and specificity of the microhemagglutination test compared favorably with the fluorescent treponemal antibody-absorption test. Since the microhemagglutination test combines desirable features of both a screening and verification procedure, it should be the test of choice for detection of T paraluis-cuniculi infection.

Animals↗
PubMed1985

Mucopolysaccharides in suspensions of Treponema pallidum extracted from infected rabbit testes.

The amount and nature of mucopolysaccharides present in extraction fluids routinely obtained in the isolation procedure of Treponema pallidum from infected rabbit testes was investigated. The mean quantity of mucopolysaccharides extracted from both testes of groups of 10 rabbits was 3.09 mg after infection for seven days and 26.88 mg after infection for 12 days, while from the testes of uninfected rabbits a mean of 0.42 mg was obtained. On electrophoresis the isolated mucopolysaccharides showed only one single band with the migration characteristics of hyaluronic acid. This band disappeared completely after pretreatment with hyaluronidase from bovine testes, which showed that during infection with T pallidum increasing amounts of hyaluronic acid accumulate. They can, at least in part, be extracted by a gentle extraction procedure, suggesting that this material binds loosely. The amount of hyaluronic acid isolated 12 days after infection showed positive correlations with the wet weight of testes as well as the number of treponemes isolated; seven days after infection such correlations were not present.

Animals↗
PubMed1986

Monoclonal antibodies directed against major histocompatibility complex antigens bind to the surface of Treponema pallidum isolated from infected rabbits or humans.

Evidence is presented for the association of class I major histocompatibility complex (MHC) antigens with the surface of Treponema pallidum during infection. A monoclonal antibody (IgG2a) directed against a murine H-2Kb epitope of public specificity reacted with the cell surface of T. pallidum, as assayed by the binding of protein A-colloidal gold in immunoelectron microscopy. Monoclonal antibodies directed against class I rabbit MHC antigens also reacted in immunofluorescence assays with material on the surface of rabbit-cultivated T. pallidum. In addition, impression smears of human syphilitic genital ulcers that were darkfield-positive for the presence of spirochetes were tested in immunofluorescence assays with monoclonal antibodies directed against human MHC antigens; antibody directed against HLA-ABC (class I) was reactive whereas antibody directed against HLA-DR (class II) was nonreactive. Results of the study suggest that the association of host-derived class I MHC antigens or molecular mimicry may play a role in T. pallidum evasion of host immune defenses.

Animals↗
PubMedDate not supplied

Nonsyphilitic spirochetosis in second-trimester fetuses.

Four female fetuses (17-23 weeks) spontaneously aborted by young women (15-19 years old) showed spirochetal microorganisms predominantly in the intestinal lumen and mucosa and to a much lesser extent in other organs. Fetal tissues showed a brisk lymphocytic-plasmacytic response in intestinal mucosa, lungs, and meninges in some cases. In all instances the placenta had chorioamnionitis and severe chronic villitis, with villous vasculitis in some. One fetus had a concomitant cytomegalovirus infection. The observed lesions were reminiscent of Treponema pallidum infections; however, the spirochetes were morphologically different by light and ultrastructural microscopy from T. pallidum and did not react with a silver-enhanced, gold-labeled anti-T. pallidum antibody. In addition, serologic tests for syphilis of the women before or after the abortions were nonreactive. On the basis of clinical pathologic considerations as well as the absence of immunostaining, it is possible also to rule out infections caused by Lyme and relapsing fever Borrelia, Leptospira, and Campylobacter. The spirochetes' prominent tropism for the intestinal tract raises the possibility of a congenital infection with gastrointestinal spirochetal species described in recent years. The placental findings suggest an ascending transamniotic infection, with initial colonization of the intestinal tract and systemic dissemination of the organisms in the fetus and placental villi.

Adolescent↗