Comparative evaluation of seven commercial tests for detection of heterophile antibody in infectious mononucleosis

Detection of heterophile antibodies in infectious mononucleosis is the most rapid and cost-effective method for confirming the clinical diagnosis of the disease. This study compared seven commercial test kits (the Oxoid Infectious Mononucleosis Kit [Oxoid Ltd], Immunoscan Im-Latex [Baxter Travenol], Mono-Latex [Wampole Laboratories], Monospot and Im Screen Test [Ortho Diagnostics], Immunoscan Im-RBC Test [Baxter Travenol], and Infectious Mononucleosis Test [NCS Diagnostics]) to the Davidsohn differential test. All of the kits were shown to be acceptable for use, with specificities and sensitivities greater than 96.5% and 95.5%, respectively.

Comparison of the Clearview Chlamydia test, Chlamydiazyme, and cell culture for detection of Chlamydia trachomatis in women with a low prevalence of infection

Two antigen detection systems, Clearview Chlamydia (Unipath Ltd., Bedford, United Kingdom) and Chlamydiazyme (Abbott Laboratories, North Chicago, Ill.), were compared with culture for the diagnosis of chlamydia infection in women attending gynecological clinics. Chlamydia trachomatis was isolated from 43 (4.5%) of the 965 women tested. In comparison with tissue culture, the Clearview Chlamydia and Chlamydiazyme tests had sensitivities of 79.0 and 74.4%, respectively, and both had a specificity of 99.6%. The results show that the Clearview Chlamydia test is comparable to Chlamydiazyme for the detection of C. trachomatis from endocervical specimens in a population with a low prevalence of infection.

Effect of dexamethasone on pulmonary inflammation and pulmonary function of ventilator-dependent infants with bronchopulmonary dysplasia

Seventeen ventilator-dependent premature infants with bronchopulmonary dysplasia (BPD) were enrolled in a double-blind, placebo-controlled study to determine the effects of 3 days of intravenously administered dexamethasone (0.5 mg/kg/day) on pulmonary function, pulmonary inflammation, and the requirement for respiratory support (FIO2, ventilator peak pressure [PP], and respiratory rate [RR]). Assessment of pulmonary function included measurement of FVC, flow at 25% vital capacity (V25), and static compliance of the respiratory system (Crs), whereas pulmonary inflammation was assessed by the neutrophil count, ratio of elastase/2 x alpha-1-antitrypsin, and the concentrations of albumin and fibronectin in the tracheobronchial lavage (TBL) fluid. After 3 days of placebo treatment there were no significant changes in any of the measured parameters. In contrast, the dexamethasone-treated group demonstrated a significant decrease in respiratory support (FIO2: 50 versus 36%; PP: 21 versus 16 cm H2O; RR: 22 versus 14 breaths/min) and improved pulmonary function (Crs: 0.63 versus 0.85 ml/cm H2O/kg; V25: 23 versus 68 ml/s/kg). In addition, pulmonary inflammation was suppressed in the dexamethasone-treated group (neutrophils: 23 versus 11 x 10(4)/mg albumin: elastase/2 x alpha-1-antitrypsin: 0.24 versus 0.10; albumin: 7.1 versus 3.5 mg/dl; fibronectin: 33 versus 17 micrograms/mg albumin). We conclude that short-term treatment with dexamethasone improves pulmonary function and suppresses pulmonary inflammation as well as decreasing the respiratory support required by ventilator-dependent premature infants with BPD.

The contribution of vision to asymmetries in manual aiming

An experiment was conducted to examine the hypothesis that the right hand system is superior in the processing of visual information. A manual aiming task utilizing four visual conditions was employed. In the full-vision (FV) condition subjects were afforded vision of both the hand and the target throughout the course of the movement. In the ambient-illumination-off (AO) condition, the room lights were extinguished at movement initiation, thus preventing vision of the moving limb. The target remained illuminated. In the target-off (TO) condition, the target was extinguished upon initiation of the movement. Ambient illumination and thus vision of the hand remained present. Finally there was a no-vision (NV) condition in which ambient illumination was removed and the target was extinguished upon initiation of the response movement. Although the manipulation of vision had potent effects upon terminal accuracy, and influenced reaction and movement time measures, the hands did not differ in the extent to which these characteristics were expressed. A left hand advantage for reaction time was observed. This may reflect a relative increase in right hemisphere involvement prior to aiming movements which are spatially complex.

Human anti-HLA-DQw2 monoclonal antibody secreted by an Epstein-Barr-virus--transformed lymphoblastoid cell line: assessment of the monoclonality, allospecificity, and target

IgM molecules were purified by the use of anti-IgM antibody-coupled Sepharose from the culture supernatant of an Epstein-Barr-virus-transformed lymphoblastoid cell line, MP1, that secretes alloantibodies possessing HLA-DQw2 specificity as defined by the cytotoxicity assay. The obtained IgM preparation was labeled with radioactive iodine-125I and fractionated by gel filtration. It contained pentameric IgM and smaller oligomeric IgMs. When tested by the direct cellular binding assay against a panel of HLA-typed cell lines, they all showed the DR3 and DR7 association pattern characteristic of DQw2. A weak but significant binding was detected for DR1, DR6, and DR9. On isoelectrofocusing, MP1 pentameric IgM gave a restricted banding pattern comparable to monoclonal IgM obtained from a patient with Waldenström's syndrome. Moreover, the pattern was identical to that of IgM purified from the culture supernatant of a defined hybrid clone, 162, that was generated by fusing MP1 cells with heteromyeloma D33 cells. The target class II molecules showed the dimeric structure that conforms to DQw2 molecules.

Evaluation of a new latex test and a new enzyme immunoassay for determination of rubella immunity

A new enzyme immunoassay (Rubenostika; Organon Teknika, Turnhout, Belgium), a new latex agglutination test (Rubalex; Orion Diagnostica, Espoo, Finland), and three other accepted methods for the determination of rubella immunity were compared with a standard hemagglutination inhibition assay. Of 224 serum samples tested, 54 (24%) were nonreactive and 24 (11%) were low titered. All procedures were very specific (94 to 100%). Rubenostika was the least sensitive method (88%), and Rubalex was the most sensitive (98%).

Polyclonal activation of CR+ and CR- B lymphocytes: the kinetics of initiation of DNA and immunoglobulin synthesis by lipopolysaccharide

B cells that carry the complement receptor (CR+) were separated from B cells that lack the complement receptor (CR-) by velocity sedimentation or by passage through C-coated Sephadex columns. The kinetics of responses to bacterial lipopolysaccharide (LPS) in both B cell subpopulations were determined in three assay procedures: 1) incorporation of radioactive thymidine into DNA; 2) incorporation of radioactive leucine into immunoglobulin; 3) enumeration of cells forming polyclonal antibody to the 2,4,6-trinitrophenyl hapten. Although both subpopulations of B cells responded to LPS, they differed in the time course. CR- B cells responded with a delay of approximately 24 hr as compared with the response of CR+ B cells. The implications to the ontogenetic status of CR+ and CR- B subpopulations are discussed.