The method of laser capture microdissection (LCM) combined with suppressive subtractive hybridization (SSH) was developed to isolate specific germ cells from human testis sections and to identify the genes expressed d...The method of laser capture microdissection (LCM) combined with suppressive subtractive hybridization (SSH) was developed to isolate specific germ cells from human testis sections and to identify the genes expressed during differentiation and development. In the present study, over 10,000 primary spermatocytes and round spermatid cells were successfully isolated by LCM. Using the cDNAs from primary spermatocytes and round spermatids, SSH cDNAs library of primary spermatocyte-specific was constructed. The average insert size of the cDNA isolated from 75 randomly picked white clones was 500 bp, ranging from 250 bp to 1.7 kb. Using the dot-blot method, a total of 421 clones were examined, resulting in the identification of 390 positive clones emitting strong signals. Partial sequence of cDNAs prepared from each clone was determined with an overall success rate of 84.4%. Genes encoding cytochrome c oxidase II and the rescue factor-humanin were most frequently expressed in primary spermatocytes, suggesting their roles involved in meiosis.展开更多
Under Type-Ⅱ progressively hybrid censoring, this paper discusses statistical inference and optimal design on stepstress partially accelerated life test for hybrid system in presence of masked data. It is assumed tha...Under Type-Ⅱ progressively hybrid censoring, this paper discusses statistical inference and optimal design on stepstress partially accelerated life test for hybrid system in presence of masked data. It is assumed that the lifetime of the component in hybrid systems follows independent and identical modified Weibull distributions. The maximum likelihood estimations(MLEs)of the unknown parameters, acceleration factor and reliability indexes are derived by using the Newton-Raphson algorithm. The asymptotic variance-covariance matrix and the approximate confidence intervals are obtained based on normal approximation to the asymptotic distribution of MLEs of model parameters. Moreover,two bootstrap confidence intervals are constructed by using the parametric bootstrap method. The optimal time of changing stress levels is determined under D-optimality and A-optimality criteria.Finally, the Monte Carlo simulation study is carried out to illustrate the proposed procedures.展开更多
Objectives: To evaluate the sensitivity and accuracy of the HPV DNA test in conjunction with thin prep cytology test as a screening method of human papillomavirus (HPV) infection. To study either the cervical erosion ...Objectives: To evaluate the sensitivity and accuracy of the HPV DNA test in conjunction with thin prep cytology test as a screening method of human papillomavirus (HPV) infection. To study either the cervical erosion is related to high risk HPV infection or to determine the mean age distribution that is more prone to HPV infection. Material and Methods: The study is a retrospective cohort implemented to determine the real performance of liquid based medium and HPV DNA testing combined in second clinical hospital of Jilin University Changchun, China. The study group included total 150 patients from January 1, 2011 to December 30, 2012. A computerized search identified patients with thin prep test results and high risk HPV DNA testing during a 2-year period was recruited. The patients were chosen after proper speculum examination followed by thin prep cytology (TCT) and HPV DNA test. Cytologic specimens were obtained with endocervical brush, which was rinsed into the vial of Cytyc. The residual samples after the cytology report were taken for reflex HPV DNA test. The manufacture protocol was followed for HPV DNA testing using Hybrid Capture II. Colposcopic biopsy was performed for the diagnosis purpose, in patients who had atypical squamous cells of undeter-mined significance (AUS-US), low grade intraepithelial lesion (LSIL) or high-grade intraepithelial lesion (HSIL) in cytology and with positive results of highrisk HPV DNA. The diagnostic criteria were based on the Bethesda System (TBS). Findings: The high risk HPV positive women with abnormal cytology had a CIN I risk of 73 (86%), whereas 35 (23.3%) high-risk HPV positive women out of 109 (72.7%) normal cytology who underwent histological biopsy had CIN I 16 (10.7%). The risk for cervical intraepithelial neoplasia (CIN) in women with high-risk HPV positive with normal cytology was higher among women invited for the first time 31 - 40 years of age 12 (8%) than among older women 1 (0.7%). Out of 44 (29.3%) women who had I degree erosion with 6 (14%) positive HPV DNA test 38 (86%) had a normal histology biopsy showing no statically significant between them. Conclusion: The data confirm that HR-HPV DNA testing is much more sensitive than cytology alone and that HPV DNA testing helps in identifying women with high risk of serious cervical disease in an efficient and medically acceptable manner. The other most significant advantage of this cervical cancer screening method is that women who are HPV DNA positive can easily and quickly referred for colposcopic examination (within one year), which could identify the precancerous and cancer stage. And those who are HPV DNA negative can safely have much longer screening intervals saving considerable costs. With mean age being 38 ± 10 years, age older than 30 years should undergo HPV DNA testing with cytology triage in primary screening. But in woman younger than 30 years using HPV DNA assay, as an initial screening step can increase the prevalence of abnormal smears and the positive predictive value of HPV followed by TCT. However, close follow-up is essential if the initial biopsy is negative because a considerable number of women may have HPV infection positive in subsequent studies.展开更多
文摘The method of laser capture microdissection (LCM) combined with suppressive subtractive hybridization (SSH) was developed to isolate specific germ cells from human testis sections and to identify the genes expressed during differentiation and development. In the present study, over 10,000 primary spermatocytes and round spermatid cells were successfully isolated by LCM. Using the cDNAs from primary spermatocytes and round spermatids, SSH cDNAs library of primary spermatocyte-specific was constructed. The average insert size of the cDNA isolated from 75 randomly picked white clones was 500 bp, ranging from 250 bp to 1.7 kb. Using the dot-blot method, a total of 421 clones were examined, resulting in the identification of 390 positive clones emitting strong signals. Partial sequence of cDNAs prepared from each clone was determined with an overall success rate of 84.4%. Genes encoding cytochrome c oxidase II and the rescue factor-humanin were most frequently expressed in primary spermatocytes, suggesting their roles involved in meiosis.
基金supported by the National Natural Science Foundation of China(71401134 71571144+1 种基金 71171164)the Program of International Cooperation and Exchanges in Science and Technology Funded by Shaanxi Province(2016KW-033)
文摘Under Type-Ⅱ progressively hybrid censoring, this paper discusses statistical inference and optimal design on stepstress partially accelerated life test for hybrid system in presence of masked data. It is assumed that the lifetime of the component in hybrid systems follows independent and identical modified Weibull distributions. The maximum likelihood estimations(MLEs)of the unknown parameters, acceleration factor and reliability indexes are derived by using the Newton-Raphson algorithm. The asymptotic variance-covariance matrix and the approximate confidence intervals are obtained based on normal approximation to the asymptotic distribution of MLEs of model parameters. Moreover,two bootstrap confidence intervals are constructed by using the parametric bootstrap method. The optimal time of changing stress levels is determined under D-optimality and A-optimality criteria.Finally, the Monte Carlo simulation study is carried out to illustrate the proposed procedures.
文摘Objectives: To evaluate the sensitivity and accuracy of the HPV DNA test in conjunction with thin prep cytology test as a screening method of human papillomavirus (HPV) infection. To study either the cervical erosion is related to high risk HPV infection or to determine the mean age distribution that is more prone to HPV infection. Material and Methods: The study is a retrospective cohort implemented to determine the real performance of liquid based medium and HPV DNA testing combined in second clinical hospital of Jilin University Changchun, China. The study group included total 150 patients from January 1, 2011 to December 30, 2012. A computerized search identified patients with thin prep test results and high risk HPV DNA testing during a 2-year period was recruited. The patients were chosen after proper speculum examination followed by thin prep cytology (TCT) and HPV DNA test. Cytologic specimens were obtained with endocervical brush, which was rinsed into the vial of Cytyc. The residual samples after the cytology report were taken for reflex HPV DNA test. The manufacture protocol was followed for HPV DNA testing using Hybrid Capture II. Colposcopic biopsy was performed for the diagnosis purpose, in patients who had atypical squamous cells of undeter-mined significance (AUS-US), low grade intraepithelial lesion (LSIL) or high-grade intraepithelial lesion (HSIL) in cytology and with positive results of highrisk HPV DNA. The diagnostic criteria were based on the Bethesda System (TBS). Findings: The high risk HPV positive women with abnormal cytology had a CIN I risk of 73 (86%), whereas 35 (23.3%) high-risk HPV positive women out of 109 (72.7%) normal cytology who underwent histological biopsy had CIN I 16 (10.7%). The risk for cervical intraepithelial neoplasia (CIN) in women with high-risk HPV positive with normal cytology was higher among women invited for the first time 31 - 40 years of age 12 (8%) than among older women 1 (0.7%). Out of 44 (29.3%) women who had I degree erosion with 6 (14%) positive HPV DNA test 38 (86%) had a normal histology biopsy showing no statically significant between them. Conclusion: The data confirm that HR-HPV DNA testing is much more sensitive than cytology alone and that HPV DNA testing helps in identifying women with high risk of serious cervical disease in an efficient and medically acceptable manner. The other most significant advantage of this cervical cancer screening method is that women who are HPV DNA positive can easily and quickly referred for colposcopic examination (within one year), which could identify the precancerous and cancer stage. And those who are HPV DNA negative can safely have much longer screening intervals saving considerable costs. With mean age being 38 ± 10 years, age older than 30 years should undergo HPV DNA testing with cytology triage in primary screening. But in woman younger than 30 years using HPV DNA assay, as an initial screening step can increase the prevalence of abnormal smears and the positive predictive value of HPV followed by TCT. However, close follow-up is essential if the initial biopsy is negative because a considerable number of women may have HPV infection positive in subsequent studies.
