Comparison of human papillomavirus detection and typing by cycle sequencing, line blotting, and hybrid capture

We compared the results of human papillomavirus (HPV) detection and typing from 781 cervical samples assayed by three methods: L1 consensus PCR followed by cycle sequencing, L1 consensus PCR with biotinylated primers followed by hybridization to a line blot, and Hybrid Capture assay. Both PCR assays used L1 consensus PCR with primers MY09 and MY11. We evaluated the amplification efficiencies of both PCR assays and also compared the specific HPV types detected by each method. The samples positive by the Hybrid Capture assay were compared to the specific types detected by the PCR-based assays. The concordance between the two PCR assays in producing an HPV amplicon visible by gel electrophoresis or in detecting any HPV type was moderate: kappa values were 0.61 (95% confidence interval [CI] = 0.56 to 0.67) and 0.51 (95% CI = 0.46 to 0.58), respectively. The McNemar test for correlated proportions indicated that biotinylated PCR was less likely to produce a band (P = 0.001) and to detect an HPV type (P = 0.001) than the other PCR assay. In comparing the Hybrid Capture assay results with the HPV types detected by the PCR-based assays, we found that positivity by the Hybrid Capture assay for a number of samples may be due to cross-hybridization with HPV types not included in the Hybrid Capture assay probe cocktails.     

Comparison of Southern transfer hybridization and dot filter hybridization for detection of cervical human papillomavirus infection with types 6, 11, 16, 18, 31, 33, and 35

A commercial dot filter hybridization kit (Virapap Kit) was compared with Southern transfer hybridization for the detection of seven types of human papillomavirus (HPV) in cervical specimens from 450 consecutive females attending a sexually transmitted diseases clinic. In comparison with Southern transfer hybridization, performed with the same probes used in the dot filter kit, the sensitivity, specificity, and positive and negative predictive values of dot filter hybridization were 90%, 94%, 74%, and 98%, respectively. Among patients with cervical cytologic dysplasia, HPV DNA was detected in 44% by dot filter hybridization and in 35% by Southern transfer hybridization. Although 26% of specimens positive by dot filter hybridization were not confirmed by Southern transfer hybridization, cervical dysplasia was detected in 5 (25%) of 20 with HPV DNA detected by dot filter hybridization alone, compared with 25 (8%) of those with no definitive evidence of HPV by either method (P = 0.009) and with 16 (30%) of 53 with HPV DNA detected by both methods (P = 0.7). The kappa statistic for interobserver and intraobserver reproducibility for interpretation of blots was similar for the two methods. The dot filter hybridization method evaluated appears to be a satisfactory alternative to Southern transfer hybridization for detection of HPV DNA.     

Some studies on the mechanism of action of antibodies to nerve growth factor.

The effects of antibodies to the nerve growth factor from mouse salivary gland were examined in vitro and in vivo. Treatment of explants of receptive ganglia with antibody and complement did not produce cell damage as judged by the ability of the tissue to respond to nerve growth factor. New-born mice experimentally depleted of or genetically deficient in key complement components were susceptible to the action of the antiserum.These results show that the effect of the antibody is independent of complement and are consistent with the view that it acts by neutralization of endogenous nerve growth factor.     

Immunologic events in pigeon breeders'' disease

The immunologic and physiologic status of a group of symptomatic and asymptomatic pigeon breeders was studied in an attempt to define the immunologic events occurring in pigeon breeders' disease. Antibody activity to antigen(s) present in pigeon dropping extract (PDE) and pigeon serum (PS) was detected in the serum of both symptomatic and asymptomatic breeders. Antibody activity, however, tended to be greater in the symptomatic pigeon breeders. When subjects were challenged with PS via aerosol, serum complement activity became depressed only in asymptomatic patients. Cellular hypersensitivity to antigens present in PDE was detected in vitro in peripheral lymphocyte populations of 4 of 5 symptomatic breeders and in none of the asymptomatic breeders; cellular hypersensitivity to antigens in PS was not demonstrated in any of the individuals tested. These findings indicate that cell-mediated hypersensitivity, as well as humoral immunologic processes, may be involved in the pathogenesis of the hypersensitivity pneumonitis found in pigeon breeders.     

Hemi-field pattern visual evoked potentials: A comparison of display and analysis techniques

Summary Three methods for analyzing the spatial organization of visual evoked potentials were compared. Pattern reversal visual evoked potentials were obtained from a single subject under three viewing conditions: stimulation of the left, right, and both visual fields. The scalp distribution of the VEP to 1 deg checks was displayed using three recording and analysis techniques: a conventional horizontal occipital array of electrodes, topographic mapping, and 3-dimensional evoked potentials. All three techniques revealed "paradoxical" lateralization of P100. The relative merits of each technique are discussed.We are grateful to Susan Hoffmann-Nader and Rebecca Clark-Bash for data collection. This research was supported in part by the Brain Research Foundation of the University of Chicago.     

Anti-Thy-1-mediated T cell activation. Role of soluble factors and expression of interleukin 2 receptors on T cells

Rabbit anti-Thy-1 antibody bound to T cells induces the appearance of T cell growth factor (interleukin 2, IL 2) receptors and the production of IL 2. IL2 receptors induction by this means occurs within a short time span, and independent of any demonstrable accessory cell. A source of exogenous or endogenous IL 2 is apparently the only requirement for proliferation after these receptors are expressed. IL 2 production, on the other hand, is accessory cell-dependent, and this help is mediated via Fc receptors on the accessory cell. IL 2 production in this model is demonstrable at 4–6 h, or earlier, and is proliferation-independent. X-irradiation actually augments apparent IL 2 production. The data are consistent with the hypothesis that a differentiated subset of T cells in any mixed population is responsible for IL 2 production.     

A comparison of three methods of scoring penile circumference changes

There are presently three widely used methods of scoring penile circumference data. The present experiment attempted to determine the ability of each method to explain the variance within a data set. A total of 19 subjects were presented with 20 photographic slides assigned to five categories: neutral, female adult, female adolescent, male adult, and male adolescent. Erectile responses to each slide were recorded and the data analyzed in terms of the raw scores, percentage of full erection, and a z-score transformation. Results indicated that the z scores captured the highest proportion of the variance (52.7%), followed by the percentage scores (32.5%), and the raw scores (30.1%). Findings are discussed in terms of their research and clinical implications.