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Abstract Objective To verify the association of high-risk human papillomavirus (hrHPV) viral load reflected by cycle threshold (Ct) values from HPV testing on Cobas4800 assay with the histologic grades of cervical lesions via analysis on the combined data from two cervical cancer screening trials and to explore the referability of Ct values in management of the abnormalities from cervical cancer primary screening. Methods We analyzed the data from Chinese Multi-Center Screening Trial (CHMUST) and BUJI Cervical Cancer Screening Study Project (BUJI Study). All data to be analyzed in this paper were related to provider-collected samples. One-way ANOVA was performed to compare the Ct values among different histological groups, and Kendall’s tau-b correlation was applied to examine the association between Ct values and cervical lesion grades. The stepwise incidence of CIN2+ and CIN3+ in every 100 HPV positive individuals were calculated according to the descending of the genotype specific Ct values. The highest Ct values related to CIN3+ incidence rate 4% (or 25%) were used as the cutoffs to distinguish low-Ct value cases from the high-Ct value ones. Results A total of 1376 women in CHUMUST and BUJI Study who were aged 30–59 and positive of hrHPV for provider-collected samples on Cobas4800 with complete data in terms of the relevant Ct values (CtV) and the histological diagnosis were included for analysis. Our data showed significant difference among different histological grades of cervical lesions in the CtV of hrHPV, HPV16-plus (positive of HPV16 only or HPV16 plus 18 and/or pooled 12-HPV), and pooled 12-HPV (P 0.05). The CIN2+ or CIN3+ incidence per 100 positives significantly increased corresponding to the descending of the CtV of hrHPV, HPV16-plus and pooled 12-HPV. Compared with high-CtV groups (CtV > 33.2 for hrHPV, CtV > 29.6 for pooled 12-HPV), the relevant risks (RRs) of CIN2+ for hrHPV and pooled 12-HPV positive groups with low-CtV (CtV ≤ 33.2 and ≤ 29.6, respectively) were 3.2 (95%CI 2.18–4.80) and 2.3 (95%CI 1.50–3.45). Similarly, the RRs of CIN3+ for hrHPV and pooled 12-HPV positive groups with low-CtV were 6.5 (95%CI 2.83–14.80) and 2.7 (95%CI 1.15–6.39), respectively. The RRs of CIN2+ for medium- (30.3 37.4) groups, and the CIN3+ incidence in low-CtV value group was nine-fold higher of that in medium-CtV ones [RRs, 9.0 (95%CI 2.89–28.10)]. In comparing with the algorithms of “HPV16-plus/18-plus + cytology ≥ ASCUS for pooled 12-HPV”, triage algorithm “HPV16-plus/18-plus + Ct value ≤ 33.2 for pooled 12-HPV” could achieve a comparable sensitivity of 93.2%. Conclusion HPV viral loads reflected by Ct values for hrHPV, HPV16-plus and pooled 12-HPV from Cobas4800 HPV testing were directly associated with the severity of cervical lesions. A lower HPV genotype-specific Ct value prompted a significantly high CIN3+ risk of 4% or higher in women positive of hrHPV, HPV16-plus or pooled 12-HPV, indicating that HPV viral load reflected by Ct values on Cobas4800 may be a promising risk indicator in management of abnormalities from primary cervical cancer screening.

Abstract Background The solid transport media is a small size card that allows fast, easy DNA extraction from a variety of biological samples. In 2016 we developed a solid media transport card; for that pilot study to control the self-collection we used a pseudo-self-collection technique. The current study expands this prior work using true self-collections and only the POI card, and aims to evaluate the solid media transport card to detect HR-HPV in self-samples compared to liquid transport media. Methods Ten thousand eight hundred eighty-five women between the ages of 30–59 with no screening for 3 years were enrolled. The self-collected sample was first applied to a new solid media transport card (Labeled as SC) then the brush placed in 6 ml ThinPrep liquid (Labeled as SL). Then a physician collected a direct endocervical specimen into ThinPrep liquid (Labeled as DL). Samples were tested with Cobas 4800 and the SeqHPV NGS assay for HR-HPV. Patients positive on any test were recalled for colposcopy and biopsy. Results Ten thousand three hundred thirty-nine participants had complete data. The mean age was 43.9 years. CIN 2+ rates were 1.4% (142/10339). The agreement in HPV detection between the two different self-sample collection media was also good (Cobas HPV kappa = 0.86; SeqHPV kappa = 0.98). Tested with Cobas, the sensitivity of Cobas-SL and Cobas-SC for CIN 2+ was95.07 and 94.37%; and for CIN3+ was 96.30, 96.30% respectively. The specificity of Cobas-SC, and Cobas-SL for CIN2+ was 88.74 and 87.35%; for CIN3 was 88.04and 86.65% respectively. Tested with SeqHPV, the sensitivity for CIN2+ of Seq-SC and Seq-SL was 95.77 and 96.48%; for CIN3+, both the SC and SL specimens had a sensitivity of 100%. The specificity for CIN2+ of Seq-SC and Seq-SL was 89.54 and 89.53%; for CIN3+ was 88.84,88.82% respectively. For both HR-HPV assays, the sensitivities were similar for the two self-sample media (SC vs SL, p = 1.00). Conclusions The solid transport card for collecting vaginal self-samples as accurate as liquid transport media assayed by two different PCR based HR-HPV tests. The solid transport media is a suitable medium for collecting and storing vaginal self-samples.

Background: This study aimed to evaluate three different patterns of cervical cancer screening strategies for detection of cervical diseases. Methods: In total, 10,186 women aged 21–70 years attending cervical screening program were recruited and cotested by human papillomavirus (HPV) assays and cytology. Three-year histological follow-up data was recorded on women with abnormal screening results, and six clinically common screening algorithms were evaluated. Results: Significantly better protection against cervical intraepithelial neoplasia 2 or worse (CIN2+) at three-year follow-up was associated with a negative HPV result than by normal cytology at baseline. HPV screening was more sensitive and less specific than cytology screening. Moreover, HPV screening with HPV16/18 and reflex cytology (atypical squamous cells of undetermined significance [ASCUS] threshold) showed a similar sensitivity (94.6% vs. 98.2%, p = 0.125) and a superior specificity as compared to cotesting reflex HPV16/18 and cytology (ASCUS threshold) for CIN2+ (95.8% vs. 95.1%, p < 0.0001), achieving a colposcopy referral rate of 5.4%, and consuming 4.8 colposcopies and 4.4 cytology tests to find one CIN2+. Conclusions: HPV screening with triage of HPV-positive women by HPV16/18 genotyping and cytology provided a good equilibrium between screening effectiveness, the number of cytology tests required, and referral rates; HPV testing was similar in sensitivity to cotesting and safer than cytology, thus especially suitable for large population-based screening programs.

We present a Monte Carlo method implementation in the code elegant for simulating Touschek scattering effects in a linac beam. The local scattering rate and the distribution of scattered electrons can be obtained from the code either for a Gaussian-distributed beam or for a general beam whose distribution function is given. In addition, scattered electrons can be tracked through the beam line and the local beam-loss rate and beam halo information recorded.

Third-generation low-emittance storage-ring light sources based on double- and triple-bend cells and undulator magnets have been in operation around the world for more than two decades. On the horizon is a new generation based on the multi-bend achromat (MBA) lattice concept promising two to three orders of magnitude higher brightness than is available in today's sources. In this paper, the challenges inherent in designing MBA lattices, as well as potential solutions, are described. Topics covered include lattice concepts, scaling of storage-ring performance, brightness optimization, nonlinear dynamics, beam lifetime and injection schemes. [ABSTRACT FROM AUTHOR]