Immunity against Helicobacter pylori: significance of interleukin-4 receptor alpha chain status and gender of infected mice

Vaccination of interleukin-4 (IL-4) receptor alpha (IL-4Ralpha) chain-deficient BALB/c mice with Helicobacter pylori urease and cholera toxin or with urease-expressing, live attenuated Salmonella enterica serovar Typhimurium cells revealed that protection against H. pylori infection is independent of IL-4- or IL-13-mediated signals. A comparison of male and female mice suggests a sexual dimorphism in the extent of bacterial colonization that is particularly evident in the absence of the IL-4Ralpha chain.     

Isolation of genital mycoplasmas and Chlamydia trachomatis in stillborn and neonatal autopsy material

Chlamydia trachomatis and the genital mycoplasmas are significantly prevalent in sexually active women. How these organisms may affect the outcome of pregnancy and the neonate was the principal thrust of this investigation. Placenta, liver, and lung tissue were cultured from Mycoplasma hominis, Ureaplasma urealyticum, Chlamydia trachomatis, and aerobic as well as anaerobic bacteria in 432 stillborn and neonatal autopsies. Genital mycoplasmas were isolated from 36 cases (8.3%). Acute chorioamnionitis and funisitis were present significantly more often in cases with genital mycoplasma than in those without these organisms. Isolation of genital mycoplasmas was not associated with an increased incidence of intrauterine fetal death, villitis, hyaline membrane disease, congenital anomalies, or polymorphonuclear leukocytes in alveolar spaces. Chlamydia trachomatis was not found in any of the sites sampled.     

Immunological properties of the human Goodpasture target antigen.

IgE rheumatoid factor activity was found to be significantly elevated (P less than 0.01) using an ELISA assay when paired synovial fluid and sera from 13 patients with active RA were compared to ten control samples. Synovial fluid IgE RF activity was higher than predicted by diffusion alone in 7/11 (64%) of the RA synovial fluids studied when coefficients of diffusion were determined. The specificity of IgE RF activity as measured by the ELISA was confirmed using immunoaffinity chromatography. Mast cells, obtained by enzymatic dispersion of rheumatoid synovial tissue, were sensitized with sera containing either IgE antibodies directed against ragweed or IgE with RF activity. Histamine was released upon challenge with anti-IgE antibodies (33.2% +/- 11), ragweed antigen E (34.6% +/- 11), or aggregated gamma globulin (47.6% +/- 17.9). No histamine release was observed if antigen challenge occurred in the absence of appropriate sensitization, with C3 anaphylatoxin, or after immunoadsorption of IgE from sera containing IgE RF activity.     

Behavioral and hormonal effects of attachment object separation in surrogate-peer-reared and mother-reared infant rhesus monkeys

Mother-reared and surrogate-peer-reared rhesus monkeys were separated from their respective attachment objects at 6 months of age and tested for the following 9 weeks to determine their home cage behavior and their pituitary-adrenocortical responses to stress. Both groups displayed a strong immediate behavioral response to separation which was characterized by increases vocalization, increased locomotion, and decreased self-play. However, the surrogate-peer-reared infants showed a subsequent recovery in their levels of self-play whereas the mother-reared infants instead developed stereotypic behavior patterns such as repetitive pacing. The 2 groups displayed similar plasma cortisol responses to weekly sessions in an apparatus equipped with animated toy “monsters.” Mother-reared but not surrogate-peer-reared subjects, however, also manifested elevated cortisol levels when an animal in an adjacent cage was captured and removed for stress testing. Mother-reared infant monkeys thus responded in a stronger and more prolonged manner to the loss of their attachment object than surrogate-peer-reared infants. These results suggest that infant rhesus monkeys form stronger attachments to monkey mothers than to inanimate surrogate mothers, a phenomenon which has not been as clearly demonstrated using other indices of attachment strength.     

Whole-blood hemagglutination inhibition test for venereal disease research laboratory (VDRL) antibodies

Nontreponemal antibody tests such as the Venereal Disease Research Laboratory (VDRL) test are carried out on serum and widely used as screening tests for syphilis. The aim of the present study was to develop a screening test for syphilis making use of whole blood and VDRL liposomes. Antibody to human red blood cells was conjugated to VDRL liposomes and reacted with a diluted sample of patient whole blood. A total of 951 samples were tested by the new test and the VDRL tube test. All 49 VDRL samples positive by the VDRL test showed inhibition of hemagglutination in the whole-blood test (sensitivity, 100%). Of 902 samples with negative results by the VDRL test, 901 caused hemagglutination when tested with the liposomes (specificity, 99.9%). The hemagglutination inhibition method tests for syphilis in a simple one-step procedure in which whole blood is added to a tube containing liposomes. The new test has potential for point-of-care testing in developing countries.     

Geriatric autopsy pathology in centenarians

The determinate causes of death, physical findings, and major pathologic findings in the organ systems of 32 patients, aged 100 years or older who died between 1921 and 1983, on whom autopsies were performed, are described. Atherosclerosis, neoplasia, and bronchopneumonia were common, but diabetes mellitus, obesity, hypertension, and cerebrovascular accident were absent or rare. Deaths from infection were fewer in the era of antibiotic usage, while cardiovascular and neoplastic deaths became more frequent during that time. The pathologic findings in our series of centenarians indicate that few of these patients died from debilitating diseases and that mortality from infection has been modified by antibiotic usage.     

Bases anatomiques des vagotomies

Résumé La réalisation des différentes vagotomies, tronculaires, sélectives, supra-sélectives, nécessite la connaissance de l'innervation parasympathique de l'estomac.La disposition modale, les variations anatomiques et les données les plus récentes des constations per-opératoires sont analysées dans cet article.     

Equalization of asymmetries of tonus in the optomotor system of rabbits

Summary Turning a rabbit on a turn-table for a few degrees induces compensatory eye-movements and results in an asymmetry of tonus in the optomotor system. If the visual input is discontinued (darkness), this asymmetry decays and the eyes drift back to the mid-position within 12–18 sec. The equalization of such asymmetries of tonus under normal conditions and under curare is described. Tonus asymmetries induced by tilting the animals about the longitudinal axis are neither compensated under visual, nor under non-visual, conditions. Recordings were taken from oculomotor neurons, and changes of their firing frequencies were used as a measure for eye movements.A preliminary report was given at the spring meeting of the German Physiological Society 1973.Supported by the Deutsche Forschungsgemeinschaft, SFB 33.     

Peptide immunogens based on the envelope region of HIV-1 are recognized by HIV/AIDS patient polyclonal antibodies and induce strong humoral immune responses in mice and rabbits

Peptide immunogens produced by novel synthesis techniques and based on envelope proteins have repeatedly proven successful in inducing anti-HIV and anti-SIV responses in addition to producing anti-peptide immunity [Vaccine 12 (8) (1994) 736; AIDS Res. Hum. Retroviruses 14 (9) (1998) 751; Vaccine (2002) 2680]. We report here the design and evaluation of synthetic peptide constructs mimicking the variability of the third variable (V3) loop, or representing the conservation of the CD4 region of HIV-1 envelope. Three peptides based on the V3 region of HIV-1 subtype C gp120 and designated multiple epitope immunogens (MEI) differ in that one was randomly branched containing a spacer (b-MEI-s), another conjugated to a tetrameric lysine core (MEIV3b(4)) and the third conjugated to poly-L-lysine (poly-L-MEI). The method of synthesis employed produced peptides that were either linear, dimeric or tetramerically branched thereby providing differing levels of conformation. In addition the peptides also differed in their levels of variability. A fourth peptide designated B138 was based on a conserved region of HIV-1 envelope. The aim of this work was to evaluate the effect of variability and level of conformation on the immunogenicity of variable region peptides (MEI's) when compared to that of a known immunogenic and conserved region peptide (B138). Anti-peptide humoral immunity induced in BALB/c mice and New Zealand White rabbits produced antigen-recognizing antibody titres of 相似文献   

Evaluation of three commercially available hepatitis C virus antibody detection assays under the conditions of a clinical virology laboratory.

BACKGROUND: Most studies evaluating antibody detection assays are conducted on samples from healthy blood donors but not on samples of hospitalized patients which can show non-specific reactions. OBJECTIVES: To compare the performance of three commercial automated assays for the detection of hepatitis C virus (HCV) antibodies, Monolisa anti-HCV Plus version 2, Axsym anti-HCV 3.0 and Vitros anti-HCV, on a population of hospitalized patients. STUDY DESIGN: The specificity of the assays was prospectively evaluated in 2020 routine serum samples. In order to assign the serostatus of each sample, those giving positive or discordant results were further tested by three immunoblots and by RT-PCR (Roche). Moreover, the sensitivity was evaluated on eight commercial HCV seroconversion panels. RESULTS: The Monolisa, Axsym and Vitros assays showed specificities of 99.64%, 99.12% and 99.33%, respectively. Concerning the sensitivity, among 49 samples, the number of positive results was 21, 24 and 24 for the Monolisa, Axsym and Vitros kits, respectively. The differences were not statistically significant at an alpha risk of 5%. CONCLUSIONS: All assays appeared to be reliable for routine screening, but there were a surprising number of indeterminate samples that could not be resolved by confirmatory tests.