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.     

Rewarding effects of the optical isomers of 3,4-methylenedioxy-methylamphetamine ('Ecstasy') and 3,4-methylenedioxy-ethylamphetamine ('Eve') measured by conditioned place preference in rats

3,4-methylenedioxy-methylamphetamine (MDMA) (‘Ecstasy’) and its analogue 3,4-methylenedioxy-methylamphetamine (MDE) (‘Eve’) are well known illicit street drugs mainly abused by young people. In spite of the actual research going on, the classification of their abuse potential remains unclear. Since secondary reinforcers are the main factors responsible for craving and relapse, the aim of our study was to assess the potency of MDMA and MDE in a second order reinforcement paradigm, i.e. conditioned place preference (CPP). For the general assessment of our study conditions, we compared MDMA with amphetamine. Unexpectedly, no significant CPP for MDMA was found in contrast to amphetamine. Detailed analysis of current literature led us to the working hypothesis that social environment is crucial for the development of CPP. In a subsequent experiment we tested the influence of housing conditions on CPP using MDMA and demonstrated that isolated animals show significant CPP compared to group-housed ones. In order to better understand the rewarding mechanisms of Ecstasy-derivatives, we tested both the racemic drugs and the pure isomers in the CPP paradigm. Both MDMA's optical isomers and racemic MDMA showed significant CPP without notable differences, while MDE and its isomers completely failed to show any significant CPP. In conclusion, the mechanism by which MDMA induces addiction is much more complicated than assumed so far and more pronounced in isolated animals. The fact that both optical isomers of MDMA led to CPP implies that at least two pathways by which MDMA induces craving behaviour exist.     

Behavioral treatment parameters with primary dysmenorrhea

Fourteen women with primary dysmenorrhea were administered four sessions of systematic desensitization (SD) by either a male or a female therapist. The following measures were taken during the flow periods before and after treatment and at a 6-month follow-up: menstrual symptom checklist, medication usage, invalid hours, and menstrual attitudes. At pretreatment, menstrually distressed women had significantly higher scores on all measures compared to a normative group and an explicitly nondistressed group. At posttreatment, treated women's scores on the dependent variables were significantly reduced. All indices were reduced to a nondistressed level at posttreatment and at 6-month follow-up. Type of dysmenorrhea (congestive vs. spasmodic), trait anxiety level, and therapist sex did not predict differential responsiveness to SD. SD did not affect frontalis EMG, peripheral blood flow, or pain threshold. A Retrospective Symptom Scale of menstrual distress was found to be highly reliable, valid, and sensitive.     

Both IFN-γ and IL-4 Induce MHC Class II Expression at the Surface of Mouse Pro-B Cells

Pro-B cells are early B-cell progenitors that retain macrophage potential. We have studied MHC class II molecules and invariant chain inducibility on four class II negative mouse pro- B-cell clones. We analyzed the effects of IL-4 and IFN-γ, which represent the major inducers of class II in the B-lymphoid and monocytic/macrophage lineages, respectively. After 48 h of treatment with either cytokine, three pro-B-cell clones (C2.13, A1.5, and F2.2) expressed intracellular invariant chain and cell-surface class II molecules. One clone (D2.1) remained negative. As already reported, more differentiated 70Z/3 pre-B cells were inducible by IL-4 only. These data suggest that the induction of class II and invariant-chain genes are subject to regulation throughout B-cell differentiation.