Multiple Sexual Partners as a Potential Independent Risk Factor for Cervical Cancer: a Meta-analysis of Epidemiological Studies

Liu, Zhi-Chang,Liu, Wei-Dong,Liu, Yan-Hui,Ye, Xiao-Hua,Chen, Si-Dong Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.9

It's known that having multiple sexual partners is one of the risk factors of human papillomavirus (HPV) infection which is a major cause of cervical cancer. However, it is not clear whether the number of sexual partners is an independent risk factor for cervical cancer. We identified relevant studies by searching the databases of MEDLINE, PubMed and ScienceDirect published in English from January 1980 to January 2014. We analyzed those studies by combining the study-specific odds ratios (ORs) using random-effects models. Forty-one studies were included in this meta-analysis. We observed that the number of sexual partners was associated with the occurrence of non-malignant cervical disease (OR=1.82, 95%CI 1.63-2.00) and invasive cervical carcinoma (OR=1.77, 95%CI 1.50-2.05). Subgroup analyses revealed that the association remained significant after controlling for HPV infection (OR=1.52, 95%CI 1.21-1.83 for non-malignant disease; OR=1.53, 95%CI 1.30-1.76 for invasive cervical carcinoma). We found that there was a non-linear relation of the number of sexual partners with both non-malignant cervical disease and invasive cervical carcinoma. The risk of both malignant and non-malignant disease is relatively stable in women with more than 4-7 sexual partners. Furthermore, the frequency-risk of disease remained significant after controlling for HPV infection.The study suggested that h aving multiple sexual partners, with or without HPV infection, is a potential risk factor of cervical cancer.

Preparation of environmentally friendly low‐cost mullite porous Ceramics and the effect of Waste Glass Powder on structure and mechanical Properties

Wei Lian,Yan Liu,Wenjie Wang,Yangtao Dong,Sheng Wang,Zhenying Liu,Yin Liu 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.9 No.2

Environmentally friendly low-cost porous ceramics are prepared with 98.2 wt% mining waste as the raw materials at 1180 °C. The glass powder forms liquid phase at high temperatures, promoting the densification of the materials. X-ray diffraction (XRD) results show that the formation of mullite is affected by sintering temperature and content of liquid phase. The enhancement in densification is verified by the scanning electron microscopy (SEM) analysis results. According to the evolution of pore structure, the effect of the glass powder on the structure is confirmed. The number ratio of pores of < 8 μm to those of 8 ~ 20 μm is varied from 7:2 to 2:7. The minimum apparent porosity is 31.22 %, while the maximum density and linear shrinkage are 1.75 g/cm 3 and 8.48 %, respectively. The flexural strength (three-point bending method) was increased from 7.47 MPa to 28.36 MPa, indicating that the addition of glass powder could increase mechanical properties of the porous ceramics. Therefore, solid wastes can be used as the resource to develop porous mullite ceramics.

Effect of reservoir properties on the heat extraction performance in multi-well production EGS

Liu Songze,Wei Jianguang,Liu Hongliang,Liu Xuemei,Yan Bingxu 한국자원공학회 2021 Geosystem engineering Vol.24 No.4

A multi-well production enhanced geothermal system (EGS) with discrete fracture network is designed for heat extraction in this study. A thermal-hydraulic numerical simulation model is established, and the effect of reservoir properties on heat extraction is investigated. The results show that the growth rate of heat extraction efficiency will decrease as the mining time increases. The initial reservoir temperature has a positive correlation with average production temperature which provides a broad space for the use of extracted thermal energy. The variation of initial reservoir pressure has little effect on the heat extraction performance. A higher matrix permeability leads to a higher average production temperature and heat extraction ratio which prompts more working fluid flow into the matrix, the heat transfer process is enhanced. Under the conditions of this study, the preferred initial reservoir temperature is 493.15 K, the matrix permeability is 10−14m2.

Estimation of the net energy requirement for maintenance in broilers

Wei Liu,Chang Hua Lin,Zheng Ke Wu,Guo Hua Liu,Hai Jie Yan,Hua Ming Yang,Hui Yi Cai 아세아·태평양축산학회 2017 Animal Bioscience Vol.30 No.6

Objective: The net energy requirement for the maintenance (NEm) of broilers was determined using regression models by the indirect calorimetry method (ICM) or the comparative slaughter method (CSM). Methods: A 2×4 factorial arrangement of treatments including the evaluation method (ICM or CSM) and feed intake (25%, 50%, 75%, or 100% of ad libitum recommended) was employed in this experiment. In the ICM, 96 male Arbor Acres (AA) birds aged d 15 were used with 4 birds per replicate and 6 replicates in each treatment. In the CSM, 116 male AA birds aged d 15 were used. Among these 116 birds, 20 were selected as for initial data and 96 were assigned to 4 treatments with 6 replicate cages and 4 birds each. The linear regression between retained energy (RE) and metabolizable energy intake (MEI) or the logarithmic regression between heat production (HP) and MEI were used to calculate the metabolizable or net energy requirement for maintenance (MEm) or NEm, respectively. Results: The evaluation method did not detect any differences in the metabolizable energy (ME), net energy (NE), and NE:ME of diet, and in the MEI, HP, and RE of broilers. The MEI, HP, and RE of broilers decreased (p<0.01) as the feed intake decreased. No evaluation method× feed intake interaction was observed on these parameters. The MEm and NEm estimated from the linear relationship were 594 and 386 kJ/kg of body weight (BW)0.75/d in the ICM, and 618 and 404 kJ/kg of BW0.75/d in the CSM, respectively. The MEm and NEm estimated by logarithmic regression were 607 and 448 kJ/kg of BW0.75/d in the ICM, and were 619 and 462 kJ/kg of BW0.75/d in the CSM, respectively. Conclusion: The NEm values obtained in this study provide references for estimating the NE values of broiler diets.

Association of Single Nucleotide Polymorphisms in the Prostaglandin-endoperoxide Synthase 2 (PTGS2) and Phospholipase A₂ Group IIA (PLA2G2A) Genes with Susceptibility to Esophageal Squamous Cell Carcinoma

Liu, Fen,Wei, Wen-Qiang,Cormier, Robert T.,Zhang, Shu-Tian,Qiao, You-Lin,Li, Xin-Qing,Zhu, Sheng-Tao,Zhai, Yan-Chun,Peng, Xiao-Xia,Yan, Yu-Xiang,Wu, Li-Juan,He, Dian,He, Yan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.4

Background: The prostaglandin-endoperoxide synthase 2 (PTGS2) and phospholipase A2 group IIA (PLA2G2A) genes encode enzymes that are involved in arachidonic acid and prostaglandin biosynthesis. Dysregulation of both genes is associated with inflammation and carcinogenesis, including esophageal squamous cell carcinoma (ESCC). We therefore hypothesized that there is an association between single nucleotide polymorphisms (SNPs) in these genes and susceptibility to ESCC. Methods: We performed a gene-wide tag SNP-based association study to examine the association of SNPs in PTGS2 and PLA2G2A with ESCC in 269 patients and 269 healthy controls from Taihangshan Mountain, Henan and Hebei Provinces, the rural area of China which has the highest incidence of esophageal cancer in the world. Thirteen tag SNPs in PLA2G2A and 4 functional SNPs in PTGS2 were selected and genotyped using a high-throughput Mass Array genotyping platform. Results: We found a modest increased risk of ESCC in subjects with the PTGS2 rs12042763 AA genotype (OR=1.23; 95% CI, 1.00-3.04) compared with genotype GG. For PLA2G2A, a decreased risk of ESCC was observed in subjects with the rs11677 CT (OR=0.51, 95%CI, 0.29-0.85) or TT genotype (OR=0.51, 95%CI, 0.17-0.96) or the T carriers (CT+TT) (OR=0.52, 95%CI, 0.31-0.85) when compared with the CC genotype. Also for PLA2G2A, rs2236771 C allele carriers were more frequent in the control group (P=0.02). Subjects with the GC (OR=0.55, 95%CI, 0.33-0.93) or CC genotype (OR=0.38, 95% CI, 0.16-0.94) or the C carriers (GC+CC) (OR=0.52, 95%CI, 0.32-0.85) showed a negative association with ESCC susceptibility. Conclusions: Our results suggest that PTGS2 and PLA2G2A gene polymorphisms may modify the risk of ESCC development.

5-Aza-2'-deoxycytidine Induces Hepatoma Cell Apoptosis via Enhancing Methionine Adenosyltransferase 1A Expression and Inducing S-Adenosylmethionine Production

Liu, Wei-Jun,Ren, Jian-Guo,Li, Ting,Yu, Guo-Zheng,Zhang, Jin,Li, Chang-Sheng,Liu, Zhi-Su,Liu, Quan-Yan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

In hepatocellular cancer (HCC), lack of response to chemotherapy and radiation treatment can be caused by a loss of epigenetic modifications of cancer cells. Methionine adenosyltransferase 1A is inactivated in HCC and may be stimulated by an epigenetic change involving promoter hypermethylation. Therefore, drugs releasing epigenetic repression have been proposed to reverse this process. We studied the effect of the demethylating reagent 5-aza-2'-deoxycitidine (5-Aza-CdR) on MAT1A gene expression, DNA methylation and S-adenosylmethionine (SAMe) production in the HCC cell line Huh7. We found that MAT1A mRNA and protein expression were activated in Huh7 cells with the treatment of 5-Aza-CdR; the status of promoter hypermethylation was reversed. At the same time, MAT2A mRNA and protein expression was significantly reduced in Huh7 cells treated with 5-Aza-CdR, while SAMe production was significantly induced. However, 5-Aza-CdR showed no effects on MAT2A methylation. Furthermore, 5-Aza-CdR inhibited the growth of Huh7 cells and induced apoptosis and through down-regulation of Bcl-2, up-regulation of Bax and caspase-3. Our observations suggest that 5-Aza-CdR exerts its anti-tumor effects in Huh7 cells through an epigenetic change involving increased expression of the methionine adenosyltransferase 1A gene and induction of S-adenosylmethionine production.

Structural evaluation of an existing steel natatorium by FEM and dynamic measurement

Liu, Wei,Gao, Wei-Cheng,Sun, Yi,Yu, Yan-Lei Techno-Press 2009 Structural Engineering and Mechanics, An Int'l Jou Vol.31 No.5

Based on numerical and experimental methods, a systematic structural evaluation of a steel natatorium in service was carried out in detail in this paper. Planning of inspection tasks was proposed firstly according to some national codes in China in order to obtain the economic and reliable results. The field visual inspections and static computation were conducted in turn under in-service environmental conditions. Further a three-dimensional finite element model was developed according to its factual geometry properties obtained from the field inspection. An analytical modal analysis was performed to provide the analytical modal properties. The field vibration tests on the natatorium were conducted and then two different system identification methods were used to obtain the dynamic characteristics of the natatorium. A good correlation was achieved in results obtained from the two system identification methods and the finite element method (FEM). The numerical and experimental results demonstrated that the main structure of the natatorium in its present status is safe and it still satisfies the demand of the national codes in China. But the roof system such as purlines and skeletons must be removed and rebuilt completely. Moreover the system identification results showed that field vibration test is sufficient to identify the reliable dynamic properties of the natatorium. The constructive suggestion on structural evaluation of the natatorium is that periodic assessment work must be maintained to ensure the natatorium's safety in the future.

Structural evaluation of an existing steel natatorium by FEM and dynamic measurement

Wei Liu,Wei-Cheng Gao,Yi Sun,Yan-Lei Yu 국제구조공학회 2009 Structural Engineering and Mechanics, An Int'l Jou Vol.31 No.5

Based on numerical and experimental methods, a systematic structural evaluation of a steel natatorium in service was carried out in detail in this paper. Planning of inspection tasks was proposed firstly according to some national codes in China in order to obtain the economic and reliable results. The field visual inspections and static computation were conducted in turn under in-service environmental conditions. Further a three-dimensional finite element model was developed according to its factual geometry properties obtained from the field inspection. An analytical modal analysis was performed to provide the analytical modal properties. The field vibration tests on the natatorium were conducted and then two different system identification methods were used to obtain the dynamic characteristics of the natatorium. A good correlation was achieved in results obtained from the two system identification methods and the finite element method (FEM). The numerical and experimental results demonstrated that the main structure of the natatorium in its present status is safe and it still satisfies the demand of the national codes in China. But the roof system such as purlines and skeletons must be removed and rebuilt completely. Moreover the system identification results showed that field vibration test is sufficient to identify the reliable dynamic properties of the natatorium. The constructive suggestion on structural evaluation of the natatorium is that periodic assessment work must be maintained to ensure the natatorium’s safety in the future.

Joint Antenna Selection and Multicast Precoding in Spatial Modulation Systems

Wei Liu,Xinxin Ma,Haoting Yan,Zhongnian Li,Shouyin Liu 한국인터넷정보학회 2023 KSII Transactions on Internet and Information Syst Vol.17 No.11

In this paper, the downlink of the multicast based spatial modulation systems is investigated. Specifically, physical layer multicasting is introduced to increase the number of access users and to improve the communication rate of the spatial modulation system in which only single radio frequency chain is activated in each transmission. To minimize the bit error rate (BER) of the multicast based spatial modulation system, a joint optimizing algorithm of antenna selection and multicast precoding is proposed. Firstly, the joint optimization is transformed into a mixed-integer non-linear program based on single-stage reformulation. Then, a novel iterative algorithm based on the idea of branch and bound is proposed to obtain the quasi-optimal solution. Furthermore, in order to balance the performance and time complexity, a low-complexity deflation algorithm based on the successive convex approximation is proposed which can obtain a sub-optimal solution. Finally, numerical results are showed that the convergence of our proposed iterative algorithm is between 10 and 15 iterations and the signal-to-noise-ratio (SNR) of the iterative algorithm is 1-2dB lower than the exhaustive search based algorithm under the same BER accuracy conditions.

Reporting quality of economic evaluations of the negotiated Traditional Chinese Medicines in national reimbursement drug list of China: A systematic review

Yan Juntao,Bao Shiyi,Liu Liu,Zhang Yu-Qing,Ming Jian,Wei Yan,Chen Yingyao 한국한의학연구원 2023 Integrative Medicine Research Vol.12 No.1

Background: Traditional Medicine (TM) has a wide uptake in most countries. In China, Traditional Chinese Medicine (TCM) is a common kind of primary health because of its beneficial effects. This review aimed to appraise the publication reporting quality of economic evaluations for selective TCM in the National Reimbursement Drug List (NRDL), Version 2020, based on the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement. Methods: Electronic databases were searched for economic evaluation that supported the TCM negotia- tions in NRDL (2020 version) published from 2001 to 2021, including PubMed, Web of Science, Embase, CNKI, WanFang, and SinoMed. The CHEERS statement was used to appraise the reporting quality of in- cluded TCM economic evaluations. Results: A total of 360 articles were retrieved, but only 38 economic evaluations met the inclusion crite- ria. None of the articles reported all items in the CHEERS checklist. The mean score of included articles is low at 10.93 ±2.62, with an average scoring rate of 51.31 ±10.53%. The least reported items included: “Characterizing heterogeneity,”“Conflicts of interest”, “Discount rate,”and “Study perspective,”with a re- porting rate of 0.00%, 5.26%, 7.89%, and 15.79%, respectively. Conclusion: An upward trend occurred in the quantity and quality of the economic evaluation publica- tions of TCM in China. TCM economic evaluations are still at an early stage, with an urgent need for improving reporting quality. It may result from research experiences or different ideas between TCM and Western Medicine. Adhering to reporting guidelines like CHEERS and educating economic evaluation in- vestigators can improve TCM economic evaluations’ reporting quality.