Overexpression of Hiwi Promotes Growth of Human Breast Cancer Cells

Wang, Da-Wei,Wang, Zhao-Hui,Wang, Ling-Ling,Song, Yang,Zhang, Gui-Zhen Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.18

The Piwi subfamily comprises two argonaute (Ago) family proteins, which are defined by the presence of PAZ and Piwi domains, with well known roles in RNA silencing. Hiwi, a human Piwi subfamily member, has been shown to play essential roles in stem cell self-renewal and gametogenesis. Recently, accumulating reports have indicated that abnormal hiwi expression is associated with poorer prognosis of multiple types of human cancers, including examples in the breast. However, little is known about details of the oncogenic role of hiwi in breast cancers. In present study, we confirmed overexpression of hiwi in breast cancer specimens and breast cancer cell lines at both mRNA and protein levels. Thus both RT-qPCR and Western blot data revealed significantly higher hiwi in intratumor than peritumor specimens, overexpression being associated with tumor size, lymph node metastasis and histological grade. Hiwi overexpression was also identified in breast cancer cell lines, MDA-MB-231 and MCF-7, and gain-of-function and loss-of-function strategies were adopted to identify the role of hiwi in the MCF-7 cell growth. Results demonstrated that hiwi expression in MCF-7 cells was significantly up- or down-regulated by the two strategies. We next evaluated the influence of hiwi overexpression or knockdown on the growth of breast cancer cells. Both cell count and colony formation assays confirmed promoting roles of hiwi in MCF-7 cells, which could be inhibited by hiwi specific blockage by siRNAs. In summary, the present study confirmed overexpression of hiwi in breast cancer specimens and breast cancer cell lines, and provided e vidence of promotion by hiwi of cell growth. The results imply an oncogenic role of hiwi in breast cancers.

SEDIMENT PROBLEMS IN TIDAL POWER STATIONS : Experience from Jiangxia Test Tidal Power Station

Da Bang Wang 한국해안해양공학회 1999 학술강연회 발표논문초록집 Vol.2 No.1

By analysis and calculation of the relative data from Jiangxia Test Tidal Power Station, it is concluded sediment will not cause big threat to the tidal power plants that are built at a narrow sea bay with less sediment content composed of fine-grained sediment. In case of deposition, sediments are mainly concentrated at the reservoir tail and the shores, which can be treated combining with land reclamation. The numerical method of one-dimensional unsteady flow equations and sediment balance equation can be used for deposition prediction on both inside and outside the reservoir and its accuracy can reach the requirement of the project design.

Numerical Study on Stress Intensity Factors for Stud Connectors of Steel–Concrete Connection

Da Wang,Benkun Tan,Lei Wang,Fanghuai Chen,Shengtao Xiang 한국강구조학회 2021 International Journal of Steel Structures Vol.21 No.5

The fatigue fracture of the stud connector is the main failure mode of the steel–concrete composite structure. Fatigue assessment of cracked stud connectors with weld details is conducted in this study by using the linear elastic fracture mechanics approach. The mixed-mode stress intensity factor is calculated by the M -integral method, and the relative crack position h c is considered. First, a 3D fi nite element model of the push-out test with stud welding details is proposed in this study, and the load–slip curve and stress distribution of the stud connector were analyzed. Then, the mixed-mode stress intensity factor was calculated by defi ning the sub-model with cracks, and the infl uence coeffi cient of the mixed-mode stress intensity factor was investigated. The important infl uencing parameters, which include the crack aspect ratio, relative crack height, stud diameter, and stud height, are combined for calculation. The mixed-mode stress intensity factor of the stud is dominated by mode I (open). The infl uence of the stud height is not observed. However, the stress intensity factor of the crack tip gradually increases with the stud diameter. The study also found the infl uence of the crack shape under various conditions. The results of this study can be used by researchers to evaluate the fatigue fracture conditions of stud connectors.

Size characterization and quantification of TiO₂ and SiO₂ in food matrix by sedimentation field-flow fractionation (SdFFF) and relative techniques

Da Wang,Meiyu Zhang,Jae-Min Oh,Jaeyeong Choi,Seungho Lee 한국분석과학회 2021 학술대회논문집 Vol.2021 No.11

TiO₂ and SiO₂ nanoparticles are widely used as food additives. It has been reported that TiO₂ and SiO₂ nanoparticles as food additives may be toxic, possibly causing cancer or other diseases. It is thus necessary to develop effective methods for analysis of physical and chemical properties of TiO₂ and SiO₂ nanoparticles. Field-flow fractionation (FFF) is a family of analytical tool for separation and characterization of polydispersed nanoparticles. Among the FFF family members, sedimentation field-flow fractionation (SdFFF) is suitable for analyzing nanoparticles based on their sizes and/or densities. In this study, SdFFF was setup, and was used to perform separation and quantitative analysis of TiO₂ and SiO₂ nanoparticles after mixing with food matrices such as sucrose or casein. This study focuses on quantitative analysis of the nanoparticles mixed in food matrix, and, to some extent, the size change of the nanoparticles in food matrix. Results show that sucrose promotes aggregation of TiO₂, resulting in an increase in the size of TiO₂ nanoparticles. Casein has essentially no effect on the dispersing of SiO₂ nanoparticles. This study demonstrates that SdFFF is a useful and reliable method for separation and quantitation of food-grade nanoparticles.

Size characterization and quantification of TiO₂ and SiO₂ in food matrix by sedimentation field-flow fractionation (SdFFF) and relative techniques

Da Wang,Meiyu Zhang,Jae-Min Oh,Jaeyeong Choi,Seungho Lee 한국분석과학회 2021 학술대회논문집 Vol.2021 No.11

TiO₂ and SiO₂ nanoparticles are widely used as food additives. It has been reported that TiO₂ and SiO₂ nanoparticles as food additives may be toxic, possibly causing cancer or other diseases. It is thus necessary to develop effective methods for analysis of physical and chemical properties of TiO₂ and SiO₂ nanoparticles. Field-flow fractionation (FFF) is a family of analytical tool for separation and characterization of polydispersed nanoparticles. Among the FFF family members, sedimentation field-flow fractionation (SdFFF) is suitable for analyzing nanoparticles based on their sizes and/or densities. In this study, SdFFF was setup, and was used to perform separation and quantitative analysis of TiO₂ and SiO₂ nanoparticles after mixing with food matrices such as sucrose or casein. This study focuses on quantitative analysis of the nanoparticles mixed in food matrix, and, to some extent, the size change of the nanoparticles in food matrix. Results show that sucrose promotes aggregation of TiO₂, resulting in an increase in the size of TiO₂ nanoparticles. Casein has essentially no effect on the dispersing of SiO₂ nanoparticles. This study demonstrates that SdFFF is a useful and reliable method for separation and quantitation of food-grade nanoparticles.

Mechanical Characteristic Analysis of Corrugated Steel Webs Using Asynchronous Construction Technology

Da Wang,Lei Wang,Cheng Tang 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.1

For application and populization of the corrugated steel web prestressed concrete (PC) composite box-girder bridge, a new asynchronous cantilever construction method was proposed to reflect the social and economic benefits of this type bridge in short term. In this paper, comparisons of the construction process and economic indexes between the traditional hanging basket cantilever construction method and the asynchronous cantilever method. Combination of the large finite element program ANSYS, a fine finite element model of the studied bridge was built, some analysis of the bridge structure were conducted for the whole process of construction, the calculation results were compared with the field testing data by the real-time monitored stress and displacement. The results indicated that the process of asynchronous cantilever construction method is simple and clear, the construction period is short and the economic indicator is high. This proposed asynchronous cantilever construction method is far superior to the traditional hanging basket cantilever construction method. The deformation and stress of structure were varied in a reasonable and safety range during the construction for the proposed method. The structural stress distribution of the proposed method is more reasonable than that of the traditional hanging basket cantilever construction method.

Characterization of TiO₂ and SiO₂ nanoparticles in food using field-flow fractionation(FFF)

Wang Da,Meiyu Zhang,Jae-Min Oh,Jaeyeong Choi,Seungho Lee 한국분석과학회 2021 학술대회논문집 Vol.2021 No.5

Prevalence and Genotype Distribution of Human Papillomavirus among Women from Henan, China

Wang, Xiao-Chuan,Sun, Liang-Qi,Ma, Li,Li, Hua-Xin,Wang, Xiu-Li,Wang, Xin,Yun, Tian,Meng, Nian-Long,Lv, Da-Le Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.17

Human papillomavirus (HPV) infection has been implicated as a causative of cervical cancer. In the present study, a total of 578 samples from females attending the gynecological outpatient clinic in Henan province, China, were collected and the HPV genotypes were detected by gene chip and flow-through hybridization. Overall, 44.5% (257/578) females were found to be HPV DNA positive, and the high risk HPV (HR-HPV) rate was 35.1% (203/578). The first peak of HR-HPV infection appeared in the >60 year-old group (55.0%), and the second was within the 51-55 year-old group (50.0%) (${\chi}^2$=19.497, p<0.05). HPV 16 was the most prevalent genotype (9.2%), followed by HPV 52 (7.8%), HPV 6 (6.9%), HPV 11 (5.9%) and HPV 42 (5.0%). The single type HPV infection was 30.4%, with the five majority prevalent genotype HPV 16 (16.5%), HPV 52 (14.3%), HPV 6 (12.6%), HPV 42 (8.6%), HPV 31 (5.1%). The multiple-type HPV infections were 14.0%, and HPV 16 was the most prevalent type (29.6%), followed by HPV 52 (24.7%), HPV 6 (22.2%), HPV 11 (22.2%), HPV 42 (17.3%) and HPV 39 (17.3%).

Identification of Biomarkers for Diagnosis of Gastric Cancer by Bioinformatics

Wang, Da-Guang,Chen, Guang,Wen, Xiao-Yu,Wang, Dan,Cheng, Zhi-Hua,Sun, Si-Qiao Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.4

Background: We aimed to discover potential gene biomarkers for gastric cancer (GC) diagnosis. Materials and Methods: Genechips of 10 GC tissues and 10 gastric mucosa (GM, para-carcinoma tissue, normal control) tissues were generated using an exon array of Affymetrix containing 30,000 genes. The differentially expressed genes (DEGs) between GC tissues and normal control were identified by the Limma package and analyzed by hierarchical clustering analysis. Gene ontology (GO) and pathway enrichment analyses were performed for investigating the functions of DEGs. Receiver operating characteristics (ROC) analysis was performed to measure the effects of biomarker candidates for diagnosis of GC. Results: Totals of 896 up-regulated and 60 down-regulated DEGs were identified to be differentially expressed between GC samples and normal control. Hierarchical clustering analysis showed that DEGs were highly differentially expressed and most DEGs were up-regulated. The most significantly enriched GO-BP term was revealed to be mitotic cell cycle and the most significantly enriched pathway was cell cycle. The intersection analysis showed that most significant DEGs were cyclin B1 (CCNB1) and cyclin B2 (CCNB2). The sensitivities and specificities of CCNB1 and CCNB2 were both high (p<0.0001). Areas under the ROC curve for CCNB1 and CCNB2 were both greater than 0.9 (p<0.0001). Conclusions: CCNB1 and CCNB2, which were involved in cell cycle, played significant roles in the progression and development of GC and these genes may be potential biomarkers for diagnosis and prognosis of GC.

Analysis of chemical compounds and toxicological evaluation of Forsythia suspensa leaves tea

Da-Hong Wang,Meng-Yang Wang,Wen-Hao Shen,Jiang-Feng Yuan 한국식품과학회 2021 Food Science and Biotechnology Vol.30 No.2

To determine the compositions of Forsythia suspensa leaves tea (FSLT) and its safety, the chemical compounds were analysed with some methods, and the toxicity was evaluated in Kunming mice and Wistar rats. The results showed that FSLT contained rich flavonoid, lignans, triperpene acids, amino acids, and mineral elements. In the acute toxicity study, none of the mice died, and no obvious poisoning symptoms were observed after 14 days in mice at the dose of 15 mg/g·body weight (bw) FSLT; in the sub-chronic toxicity, no abnormal or dead rat was found at the dose of 1, 3, and 10 mg/g·bw during 90 days feeding administration; there was no significant difference in bw and food consumption; no significant differences were found in each hematology and serum biochemistry parameter and organ/body weight ratio comparing with the control experimental group. The results revealed that the FSLT has low or no toxicity via oral administration. Therefore, FSLT is very suitable and safe to be used as a new resource food.