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31.
BACKGROUND: Type-specific persistence of human papillomavirus (HPV) infection can cause invasive cervical cancer. OBJECTIVES: To evaluate the efficacy of HPV detection and typing with a general polymerase chain reaction (PCR)-based genotyping array and to compare it with a type-specific PCR assay. STUDY DESIGN: Four hundred and thirty-three cervical samples were tested with a modified MY11/GP6+ PCR-based reverse-blot assay (EasyChip HPV Blot; King Car, Taiwan [hereafter HPV Blot]) and with 20 genotypes of L1-type-specific PCR (HPV-6, -11, -16, -18, -31, -33, -35, -39, -45, -51, -52, -53, -56, -58, -59, -62, -66, -68, -70, and -71 [CP8061]). RESULTS: The concordance of the two tests in determining HPV positivity was 96.8% (419/433), with a Cohen's kappa=0.93 (95% CI: 0.90-0.97) and McNemar's test of P=1.0, which indicates excellent agreement. The overall concordance of the two tests in the identification of type-specific HPV was 91.0% (394/433). Sensitivity (90-100%), specificity (99.2-100%), and accuracy (98.6-100%) rates of HPV Blot against the gold standard were satisfactory for HPV-16, -18, -58, -33, -52, -39, -45, -31, -51, -70 while HPV-71 (63.6%) had suboptimal sensitivity. Though the kappa values between the two tests for many individual genotypes could not be reliably calculated because of low positivity, the kappa values for HPV-16, -52, and -58 were excellent (0.93, 0.96, and 0.95, respectively). CONCLUSION: The modified MY11/GP6+ PCR-based HPV Blot assay is accurate and sensitive for detection and genotyping of HPV in cervical swab samples.  相似文献   
32.
Despite the high prevalence of cervical cancer and cervical neoplasias in South Africa, few studies have been performed in this region to establish which human papillomavirus (HPV) types are associated with the development of high-grade cervical intraepithelial neoplasia lesions and cervical cancer. To investigate these prevalence rates, punch biopsies were obtained from 56 women with cervical cancer and 141 women with histologically diagnosed cervical intraepithelial neoplasia 2 or 3 lesions. Nested polymerase chain reaction (PCR) using consensus degenerate PCR primers was performed for the detection of HPV DNA and HPV typing was done by restriction fragment length polymorphism. Forty-seven (94%) of the cervical cancer and 114 (88%) of the cervical intraepithelial neoplasia 2/3 biopsies were positive for HPV DNA. The prevalence rates of the HPV types detected in the cervical cancer biopsies were HPV 16 (82%), HPV 18, (10%), HPV 33 (10%), HPV 31 (2%), HPV 58 (2%), HPV 35 (2%), and HPV 59 (2%). The cervical intraepithelial neoplasia lesions contained HPV 16 (56.6%), HPV 33 (14%), HPV 31 (10.9%), HPV X (7%), HPV 52 (3.9), HPV 58 (3.1%), HPV 35 (2.3%), HPV 18 (1.6%), HPV 11 (0.8%). Five of the nine fragments that were not typed by the RFLP, designated HPV-X, were sequenced to give HPV6 (1/5), HPV 26 (2/5), HPV 68 (1/5), and candHPV 87 (1/5). HPV 58 was detected in one cervical cancer biopsy and four biopsies from cervical intraepithelial neoplasia grade 3 lesions and was shown to be a previously described variant [Williamson and Rybicki (1991) J. Med. Virol. 33:165-171]. In addition, a cervical intraepithelial neoplasia grade 2 lesion was shown to harbour HPV type HAN2294 (cand HPV 87). The results of this study indicate that cervical cancer and cervical intraepithelial neoplasia 2/3 are largely associated with HPV 16 infection in this group of South African women and, therefore, an effective HPV 16 based vaccine should prevent the development of cervical cancer in a large proportion of women from this region of South Africa.  相似文献   
33.
While HPV 16 variant lineages have been well characterized, the knowledge about HPV 18 variants is limited. In this study, HPV 18 nucleotide variations in the E2 hinge region were characterized by sequence analysis in 47 control and 51 tumor specimens. Fifty of these specimens were randomly selected for sequencing of an LCR-E6 segment and 20 samples representative of LCR-E6 and E2 sequence variants were examined across the L1 region. A total of 2770 nucleotides per HPV 18 variant genome were considered in this study. HPV 18 variant nucleotides were linked among all gene segments analyzed and grouped into three main branches: Asian-American (AA), European (E), and African (Af). These three branches were equally distributed among controls and cases and when stratified by Hispanic and non-Hispanic ethnicities. Among invasive cervical cancer cases, no significant differences in the three HPV variant branches were observed among ethnic groups or when stratified by histopathology (squamous vs. adenocarcinoma). The Af branch showed the greatest nucleotide variability when compared to the HPV 18 reference sequence and was more closely related to HPV 45 than either AA or E branches. Our data also characterize nucleotide and amino acid variations in the L1 capsid gene among HPV 18 variants, which may be relevant to vaccine strategies and subsequent studies of naturally occurring HPV 18 variants. Several novel HPV 18 nucleotide variations were identified in this study.  相似文献   
34.
In view of the dual burden of HIV infection and cervical cancers in India, this study was undertaken to estimate the prevalence of Pap smear abnormalities and human papillomavirus infection among HIV-infected women. Consecutive HIV-infected women attending voluntary counseling testing clinics were enrolled. Written informed consent, demographic information, Pap smears, cervical swabs for HPV typing and a blood sample for CD4+ cell count were collected. Treatment for opportunistic and sexually transmitted infections and reproductive tract infections was provided. Women with Pap smear abnormality were referred for further intervention. Between January 2003 and May 2004, 287 HIV-infected women were enrolled. Pap smear abnormalities were seen in 6.3% women and were more common among women aged 30 and above (P=0.042) and those who had suffered from opportunistic infections (P=0.004). In multivariate analysis, Pap smear abnormalities were associated independently with opportunistic infections (P=0.02, AOR 3.8, 95% CI 1.2--11.5). Of the 100 random cervical specimens screened for HPV 16 and 18 genotypes, 33% (95 CI 23.9--43.1) were positive for HPV 16/18. Of the 122 patients who returned for a follow-up visit, 5 patients (4.1%) who did not have Pap smear abnormality at baseline, had developed Pap smear abnormality. The incidence of Pap smear abnormalities was 5.5 per 100 person year of follow-up. In order to prevent thousands of deaths due to cervical cancer in India, there is a need for strengthening the Pap smear screening program and HPV vaccine development.  相似文献   
35.
目的 了解慢性宫颈炎患者感染人乳头瘤病毒(HPV)的情况。方法 随机抽取慢性宫颈炎患者252例,根据免疫组化检测结果分为两组:HPV-Ag阳性组和HPV-Ag阴性组,对比两组患者的年龄、临床表现,并行宫颈细胞学检查、阴道检查、病理活检,随后行宫颈电灼治疗,观察宫颈愈复情况及HPV-Ag是否转阴。结果 宫颈炎中HPV感染率为14.68%,感染后临床症状较HPV-Ag阴性组重,阴道细胞学检查多为Ⅱ级或Ⅲ级,阴道镜下多为不典型转变区,病理切片可见空泡细胞。经电灼治疗后,阳性组70.27%患者宫颈HPV-Ag可转阴。结论 治疗HPV-Ag 阳性的慢性宫颈炎病人对预防宫颈癌有积极意义。  相似文献   
36.
BackgroundHuman papillomavirus (HPV) vaccine has been increasingly discussed in mainland China since its first approval in 2016. To date, nearly all studies assessing HPV vaccine perceptions and attitudes were implemented during pre-licensure period. Therefore, the nationwide post-marketing survey was conducted to update knowledge, attitudes and practice on HPV vaccine among general population in mainland China.MethodsParticipants aged 18–45 years living in mainland China were recruited in April 2019 by multi-stage non-randomized sampling. Sociodemographic factors, HPV and HPV vaccine related awareness, knowledge, attitudes, vaccine uptake and potential obstacles were assessed in questionnaires. Bivariate analysis and multivariate regression were used to identify disparity among subgroups with different sociodemographic characteristics.Results4,000 women (32.1 ± 7.81y) and 1,000 men (31.8 ± 7.96y) were included in final analysis. Less than one third of participants had heard of HPV (female: 31%; male: 22%) and HPV vaccine (female: 34%; male: 23%). Knowledge score was also unfavorable on HPV (female: 3 out of 13; male: 1.8 out of 13) and HPV vaccine (female: 3 out of 6; male: 2 out of 5). Only 3% females had been vaccinated three years after HPV licensure in China, although willingness to get vaccinated among those unvaccinated were high (mean willingness score ± SD: female: 3.3 ± 0.97; male: 3.0 ± 0.98). Industry of employment and household income were the major factors related to awareness and knowledge of vaccine, whereas HPV and HPV vaccine awareness were key influential factors for willingness. The main obstacles of vaccination were safety concerns, lack of knowledge, and high price of HPV vaccines.ConclusionsFindings highlight a lack of vaccine awareness, knowledge, and poor uptake in mainland China and underscore the necessity of health education campaigns. The identified priority groups, contents to be delivered and practical obstacles could furthermore provide insight into health education to reduce disparities and accelerate HPV vaccine roll-out in China.  相似文献   
37.
《Vaccine》2021,39(29):3916-3925
BackgroundHuman Papillomavirus (HPV) vaccine coverage in France is below 30%, despite proven effectiveness against HPV infections and (pre-)cancerous cervical lesions. To optimise vaccine promotion among adolescents, we used a discrete choice experiment (DCE) to identify optimal statements regarding a vaccination programme, including vaccine characteristics.MethodsGirls and boys enrolled in the last two years of five middle schools in three French regions (aged 13–15 years) participated in an in-class cross-sectional self-administered internet-based study. In ten hypothetical scenarios, participants decided for or against signing up for a school-based vaccination campaign against an unnamed disease. Scenarios included different levels of four attributes: the type of vaccine-preventable disease, communication on vaccine safety, potential for indirect protection, and information on vaccine uptake among peers. One scenario was repeated with an added mention of sexual transmission.ResultsThe 1,458 participating adolescents (estimated response rate: 89.4%) theoretically accepted vaccination in 80.1% of scenarios. All attributes significantly impacted theoretical vaccine acceptance. Compared to a febrile respiratory disease, protection against cancer was motivating (odds ratio (OR) 1.29 [95%-CI 1.09–1.52]), but not against genital warts (OR 0.91 [0.78–1.06]). Compared to risk negation (“vaccine does not provoke serious side effects”), a reference to a positive benefit-risk balance despite a confirmed side effect was strongly dissuasive (OR 0.30 [0.24–0.36]), while reference to ongoing international pharmacovigilance without any scientifically confirmed effect was not significantly dissuasive (OR 0.86 [0.71–1.04]). The potential for indirect protection motivated acceptance among girls but not boys (potential for eliminating the disease compared to no indirect protection, OR 1.57 [1.25–1.96]). Compared to mentioning “insufficient coverage”, reporting that “>80% of young people in other countries got vaccinated” motivated vaccine acceptance (OR 1.94 [1.61–2.35]). The notion of sexual transmission did not influence acceptance.ConclusionHPV vaccine communication to adolescents can be tailored to optimise the impact of promotion efforts.  相似文献   
38.
《Vaccine》2021,39(25):3435-3444
PurposeYoung adulthood is characterized by changes in health care decision-making, insurance coverage, and sexual risk. Although the human papillomavirus (HPV) vaccine is now approved for adults up to age 45, and catch-up vaccination is currently recommended up through age 26, vaccination rates remain low in young adults. This study explored perspectives on HPV vaccination among young adults receiving care at the student health center of a large public university.MethodsWe conducted semi-structured interviews (n = 27) and four focus groups with female and male undergraduate and graduate students (n = 18) and semi-structured interviews with health care providers (n = 6). Interviews and focus groups explored perceived risk of HPV infection, benefits of the HPV vaccine, and motivations for and barriers to HPV vaccination.ResultsMany young adults cited their parents’ views and recommendations from medical providers as influential on their decision-making process. Students perceived that cervical cancer prevention was a main benefit of the HPV vaccine and sexual activity was a risk factor for HPV infection. Students often lacked knowledge about the vaccine’s benefits for males and expressed some concerns about the safety and side effects of a vaccine perceived as new. Logistical barriers to vaccination included uncertainty over vaccination status and insurance coverage for the vaccine, and concerns about balancing the vaccine schedule with school obligations. Providers’ vaccine recommendations were impacted by health system factors, including clinical infrastructure, processes for recommending and documenting vaccination, and office visit priorities. Suggested vaccination promotion strategies included improving the timing and messaging of outreach efforts on campus and bolstering clinical infrastructure.ConclusionsAlthough college may be an opportune time to reach young adults for HPV vaccination, obstacles including navigating parental influence and independent decision-making, lack of awareness of vaccination status, and numerous logistical and system-level barriers may impede vaccination during this time.  相似文献   
39.
Sensitive high-throughput neutralization assays, based upon pseudoviruses carrying a secreted alkaline phosphatase (SEAP) reporter gene, were developed and validated for human papillomavirus (HPV)16, HPV18, and bovine papillomavirus 1 (BPV1). SEAP pseudoviruses were produced by transient transfection of codon-modified papillomavirus structural genes into an SV40 T antigen expressing line derived from 293 cells, yielding sufficient pseudovirus from one flask for thousands of titrations. In a 96-well plate format, in this initial characterization, the assay was reproducible and appears to be as sensitive as, but more specific than, a standard papillomavirus-like particle (VLP)-based enzyme-linked immunosorbent assay (ELISA). The neutralization assay detected type-specific HPV16 or HPV18 neutralizing antibodies (titers of 160-10240) in sera of the majority of a group of women infected with the corresponding HPV type, but not in virgin women. Sera from HPV16 VLP vaccinees had high anti-HPV16 neutralizing titers (mean: 45000; range: 5120-163840), but no anti-HPV18 neutralizing activity. The SEAP pseudovirus-based neutralization assay should be a practical method for quantifying potentially protective antibody responses in HPV natural history and prophylactic vaccine studies.  相似文献   
40.
The role of tumour suppressor genes in the development of human cancers has been studied extensively. In viral carcinogenesis, the inactivation of suppressor proteins such as retinoblastoma (pRb) and p53, and cellular oncogenes overexpression, such as c-myc, has been the subject of a number of investigations. In uterine-cervix carcinomas, where high-risk human papillomavirus (HPV) plays an important role, pRb and p53 are inactivated by E7 and E6 viral oncoproteins, respectively. However, little is known about the in situ expression of some of these proteins in pre-malignant and malignant cervical tissues. On the other hand, it has also been demonstrated that c-myc is involved in cervical carcinogenesis, and that pRb participates in the control of c-myc gene expression. By using immunostaining techniques, we investigated pRb immunodetection pattern in normal tissues, squamous intraepithelial lesions (SILs) and invasive carcinomas from the uterine cervix. Our data show low pRb detection in both normal cervical tissue and invasive lesions, but a higher expression in SILs. C-Myc protein was observed in most of the cellular nuclei of the invasive lesions, while in SILs was low. These findings indicate a heterogeneous pRb immunostaining during the different stages of cervical carcinogenesis, and suggest that this staining pattern could be a common feature implicated in the pathogenesis of uterine-cervix carcinoma.  相似文献   
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