The clinical performance of The BD Onclarity HPV Assay with respect to histology end points was similar to HC2. Moreover, discordant analysis revealed improved performance of the BD assay with respect to ability to provide extended genotyping information and lack of cross-reactivity with low-risk HPV types associated with cellular abnormalities. The relative risks for CIN 3 disease for HPV 31 and HPV 33/58 (combined) were comparable to that of HPV 18 in this population, suggesting that these genotypes may warrant monitoring in future studies.
In the United States, human papillomavirus (HPV) DNA testing is now used (12, 18) (i) as a triage test for determining whether a woman with atypical squamous cells of undetermined significance (ASC-US) needs immediate colposcopic evaluation and (ii) as an adjunct to cervical cytology, "cotesting," for cervical cancer screening of women 30 and older. HPV assays must balance clinical sensitivity with specificity to minimize both false-negative and false-positive results (10,17). Validation studies are needed to demonstrate this balance. In addition, the detection of some individual HPV genotypes, specifically HPV16 and HPV18, the two most carcinogenic HPV genotypes, may be clinically useful for those being screened with HPV in deciding which of the many HPV-positive women with negative cytology need immediate colposcopy (8,18). With these goals in mind, we evaluated a new HPV test developed by BD Diagnostics (Sparks, MD) for its analytic and clinical performance using a random sample of archived enrollment specimens from the ASCUS and Low-Grade Squamous Intraepithelial Lesion (LSIL) Triage Study (ALTS) group.Study design and population. ALTS ( .) The National Cancer Institute and local institutional review boards approved the study, and all participants provided written, informed consent.At enrollment and follow-up visits over the 2-year duration, all women underwent a pelvic examination with collection of two cervical specimens, the first specimen in PreservCyt for ThinPrep cytology (Cytyc Corporation, Marlborough, MA; now Hologic) and the second in specimen transport medium (STM; Digene Corporation, Gaithersburg, MD; now Qiagen). Women in all three arms of the study were reevaluated by cytology every 6 months during the 2 years and sent to colposcopy if the cytology result was high-grade squamous intraepithelial lesion (HSIL). An exit examination with colposcopy was scheduled for all women. We refer readers to other references for details on randomization, examination procedures, patient management, and laboratory and pathology methods (1-3, 13, 16).HPV testing. Hybrid Capture 2 (HC2; Qiagen) testing was performed on the PreservCyt specimen throughout the trial in accordance with the manufacturer's instructions (13). Line Blot Assay (LBA; Roche Molecular Systems, Alameda, CA) for the detection of 27 or 38 HPV genotypes and Linear Array (LA; Roche) for detection of 37 of 38 HPV genotypes detected by LBA (excluding HPV57) were conducted on STM specimens as previously described (4,7,11,14).BD Viper HPV assay testing was performed on aliquots of 500 randomly selected enrollment STM specimens which had been archived at Ϫ80°C. We restricted the selection to using only enrollment STM specimens with 3 or more aliquots remaining to preserve ALTS as a resource for future validation studies. Testing was done masked to the previous test results and clinical outcomes.An aliquot of 25 l of each specimen was diluted with 475 l of deionized water and then combined with 1.5 ml of a proprietary BD HPV diluent. The sample input vo...
We evaluated the effect of storage at 2 to 8°C on the stability of human genomic and human papillomavirus (HPV) DNA stored in BD SurePath and Hologic PreservCyt liquid-based cytology media. DNA retained the ability to be extracted and PCR amplified for more than 2.5 years in both medium types. Prior inability to detect DNA in archived specimens may have been due to failure of the extraction method to isolate DNA from fixed cells. Liquid-based cytology (LBC) media (BD SurePath [Becton, Dickinson and Company] and Hologic PreservCyt [Hologic Inc.]) are routinely used to prepare liquid Pap preparations for cervical cancer screening. In the United States, molecular human papillomavirus (HPV) testing out of the LBC vial is recommended (i) as a triage test for determining whether a woman with atypical squamous cells of undetermined significance (ASC-US) needs immediate colposcopic evaluation and (ii) as an adjunct to cervical cytology, "cotesting," for cervical cancer screening of women of age 30 years and older. In addition, there is a growing interest in the use of LBC media for primary HPV screening in which positive specimens could be reflexed to cytology, HPV type-specific genotyping, or another triage method, although molecular tests have yet to be approved for this intended use (1, 2). LBC media were originally developed and approved for the preservation and preparation of cells for Pap smear evaluation (3, 4). BD SurePath and Hologic PreservCyt media are both alcohol-based preservatives and are designed to fix cellular and subcellular components and aid in the cytological evaluation of the obtained smears. Fixative solutions can prove problematic for downstream molecular extraction methods because of the potential to inhibit cellular lysis, because of the potential to interfere with the proteolytic enzymes used in this process, or due to cross-linking of nucleic acids and proteins (5, 6). Some prior studies have reported poor recovery of nucleic acids from SurePath and PreservCyt media and inferred that the DNA had degraded over time during storage (7-10). SurePath medium contains a low concentration of formalin, which is known to cross-link nucleic acids and protein (11,12). Formalin treatment results in reversible cross-linking of proteins to DNA, which can render it refractory to magnetic-or silica-based purification and subsequent downstream nucleic acid biochemistry, such as PCR (13). Cross-linking can be removed using proteinase K digestion and/or heat (14-16).We have developed a simple, one-step chemical lysis method for use with the BD hrHPV-GT assay that can process 0.5 ml of either LBC specimen without prior cell harvesting or the use of lytic enzymes. The method uses a combination of heat and chemicals to lyse LBC-preserved cells directly in the media. It also efficiently reverses cross-linking effects and allows biologically active DNA to be extracted directly from the resulting lysate (17-19).The objective of the current study was to examine the effect of long-term storage of LBC specimens at 2 ...
Aztreonam (SQ 26,776) is the first parenteral monobactam agent to be used in patient trials. The agent has significant activity in vitro against facultative aerobic gram-negative bacteria but not against gram-positive or anaerobic bacteria. Aztreonam was used for a year to treat 106 hospitalized patients with a total of 131 documented gram-negative infections. Important exclusion criteria included granulocytopenia, hyperbilirubinemia, meningitis, patients less than 13 years of age, pregnancy, and history of anaphylaxis to penicillin. In this study of 35 men and 71 women, there were 67 cases of pyelonephritis (25% bacteremic), 19 of pneumonia (16% bacteremic), 10 of skin or soft-tissue infections, 9 cases of osteomyelitis, and 6 cases of postpartum endometritis. During the study period, 159 facultative aerobic gram-negative bacteria were tested for aztreonam susceptibility, and 144 (91%) were found to be susceptible. Eighty percent of infections were cured by both clinical and microbiological criteria and each of the other 26 infections showed clinical improvement. Eradication of the infecting organism was achieved in 89% of infections without adverse reaction or drug toxicity.
The relative amounts of two isoacceping species of tyrosine transfer ribonucleic acid, tRNATyrI and tRNATyrII, determined from reversed phase 5 profiles of tyrosyl-tRNA, prepared from Bacillus subtilis strain W168, were growth phase and medium dependent. The growth phase-dependent alterations in the relative amounts of tRNATyr species were also demonstrated in 11 asporogenous strains of B. subtilis. The proportion of tRNA-Tyr species and the extent of the alteration in their relative amounts during the transition from the exponential to the stationary phase of growth of these strains was not directly correlated with the formation of spores by strain W168 grown in various media or the stage at which the asporogenous strains are blocked in the process of sporulation.
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