Analysis of Different Activation Statuses of Human Mammary Epithelial Cells from Young and Old Groups

Feng, Chen-Chen,Chen, Li-Na,Chen, Mei-Jun,Li, Wan,Jia, Xu,Zhou, Yan-Yan,He, Wei-Ming Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.8

Human mammary epithelial cells have different proliferative statuses and demonstrate a close relationship with age and cell proliferation. Research on this topic could help understand the occurrence, progression and prognosis of breast cancer. In this article, using significance analysis of a microarray algorithm, we analyzed gene expression profiles of human mammary epithelial cells of different proliferative statuses and different age groups. The results showed there were significant differences in gene expression in the same proliferation status between elderly and young groups. Three common differentially expressed genes were found to dynamically change with the proliferation status and to be closely related to tumorigenesis. We also found elderly group had less status-related differential genes from actively proliferating status to intermediate status and more statusrelated differential genes from intermediate status than the young group. Finally, functional enrichment analyses allowed evaluation of the detailed roles of these differentially-expressed genes in tumor progression.

Directed Evolution and Mutagenesis of Lysine Decarboxylase from Hafnia alvei AS1.1009 to Improve Its Activity toward Efficient Cadaverine Production

Chen Wang,Kai Zhang,Chen Zhongjun,Heng Cai,Wan Honggui,Ping-Kai Ouyang 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.3

Lysine decarboxylase (LDC) exhibits a significant role in cadaverine (1,5-pentanediamine, diaminopentane) production from lysine. In this study, an error-prone PCR and DNA shuffling were performed to improve the activity of LDC from Hafnia alvei AS1.1009 for cadaverine production. A sensitive high-throughput screening strategy based on a pH indicator was established for directed evolution of LDC. Several improved mutants were obtained from directed evolution and LDCV147F/E583G mutant showed highest activity to catalyze lysine to cadaverine. This mutant showed 1.62-fold high LDC activity when compared to wild-type. Further analysis by site-directed mutagenesis reveled that only the mutant E583G was sufficient for higher catalytic activity. Wild type LDC and mutant LDCE583G were purified by an improved method including hydrophobic chromatography. These purified enzymes were characterized and the kinetic parameters were compared between LDCE583G and WT LDC. Vmax of LDCE583G was 1.32-fold higher than that of WT LDC. Use of LDCE583G mutant showed 1.48-fold improved productivity of cadaverine when compared to wild type. The concentration of cadaverine in E. coli JM109/pTrc99a-ldc2-41 was 63.9 g/L with conversion yield of 93.4% during 5 h. These results indicate that the mutation has positive effects on improving LDC activity and a potential candidate for cadaverine production.

Image Watermarking Scheme Based on Scale-Invariant Feature Transform

( Wan-li Lyu ),( Chin-chen Chang ),( Thai-son Nguyen ),( Chia-chen Lin ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.10

In this paper, a robust watermarking scheme is proposed that uses the scale-invariant feature transform (SIFT) algorithm in the discrete wavelet transform (DWT) domain. First, the SIFT feature areas are extracted from the original image. Then, one level DWT is applied on the selected SIFT feature areas. The watermark is embedded by modifying the fractional portion of the horizontal or vertical, high-frequency DWT coefficients. In the watermark extracting phase, the embedded watermark can be directly extracted from the watermarked image without requiring the original cover image. The experimental results showed that the proposed scheme obtains the robustness to both signal processing and geometric attacks. Also, the proposed scheme is superior to some previous schemes in terms of watermark robustness and the visual quality of the watermarked image.

Competitive Hydrogen-Bonding-Induced Microphase Separation in Thermosets with Triblock Copolymer

Chen-Yu LIAO,Wen-Hua CHEN,Yeo-Wan CHIANG,Chih-Feng HUANG 한국고분자학회 2016 한국고분자학회 학술대회 연구논문 초록집 Vol.41 No.2

Comparison of Subjective Refraction Findings in Two Different Levels of Room Illumination Using Three Different Types of Letter Charts

Chen, Ai-Hong,Norazman, Fatin Nur Najwa,Buari, Noor Halilah,Ahmad, Azmir,Omar, Wan Elhami Wan The Korean Ophthalmic Optics Society 2010 한국안광학회지 Vol.15 No.1

Purpose: The effect of two different levels of illumination and the effect of three letter chart types on subjective refraction findings were investigated. Methods: This study involved thirty Malay university students aged between 19 to 23 years old (7 males, 23 females), with their spherical refractive error ranged between plano to -7.75D astigmatism ranged from plano to -1.75D, anisometropia less than 1D and with no history of ocular injury and pathology. Monocular subjective refraction was measured under two levels of illumination (with and without room light) and with three different letter charts (Snellen letter chart, wall mounted letter chart and projected letter chart). Subjective refraction finding was calculated in spherical equivalent in unit diopter (D). Results: There was no significant effect in the subjective refraction findings with Snellen letter chart (t-test=0.15, p-value=0.88), projected letter chart (t-test=-0.19, p-value=0.85) as well as wall mounted letter chart (t-test=0.12, p-value=0.94). One Way ANOVA also revealed when the subjective refractive measures were compared under two different level of room illumination (with and without room light), no significant effect of letter chart types on subjective refraction readings with room light ($F_{2.185}$=0.11, p-value=0.89) and without room light ($F_{2.185}$=0.02, p-value=0.98). Conclusions: Subjective refraction findings were not affected whether the room light was on or off. They were also not affected by the types of letter chart used.

Analysis on the Co-channel Interference for the Coexistence of PS-LTE and LTE-R Networks

Wan Chen,Ishtiaq Ahmad,KyungHi Chang,Jin-Kyu Choi,Hanbyeog Cho 한국통신학회 2016 한국통신학회 학술대회논문집 Vol.2016 No.6

The Safety Management & Liability on GMO Products in China

Chen I-wan 원광대학교 법학연구소 2010 의생명과학과 법 Vol.4 No.-

The paper reviews how China’s policy of providing the devel opment of genetic engineering of crops with high priority massive fundin g absolute support was formed. China’s existing legal framework and go vernment management regulations of GMO and its safety. Most importan t developments in R&D, trials, commercialize planting of GM crops and consequences. Sino-American trade conflicts over massive imports of GM products and consequences. A series of serious facts raising great concern about GM food safety in China. Reveals that China’s national st andard does not establish any standard on the glyphosate maximum allo wed residue level of GM soybeans, soy milk and powder, toufu and all other soybean products. Spread of illegal grown unapproved GM rice. T he commercialization of GM Bt-cotton in fact is a failure but how it wa s glorified into a "success"! Suspicious animal abnormality phenomena a nd its possible link with GM suspect corn. Reactions of the concerned departments to such cases. Suspicious widespread trend of deteriorating human reproduction capabilities of young men and women in China. All of this shows that The present GMO safety legal framework is incompl ete, not effective and lack of comprehensive. Reveals how the Ministry of Agriculture resists further regulation restrictions on GM safety. A ge neral conclusion: Providing unconditional massive funding absolute supp ort to the promotion of GM technology is a fatal strategic mistake! Different to most other researchers, the author has crossed into the f ield of studying GMO safety from two other fields, (1) disaster preventi on, and (2) science & technology innovation sociology. From angles of studies in disaster prevention, when studying the issu e of GMO safety, the author focuses on what aspects already cause or have the potential of causing the most serious and widespread disaster s to human health and the environment in China, their reasons, and pos sible preventative measures. From angles of studies in science & technology innovation sociology, when studying the issue of GMO safety, the author focuses on the follo wing questions: Is genetic engineering a science & technology innovatio n? Is it promoting advance in science, or reverse? Is it promoting other science & technology innovation in the concerned fields, or is it suppre ssing other science & technology innovation in the concerned fields? O r, in other words, is it blocking science advancement? The present paper can not cover all these respects, but, for the first time, provides scholars outside China a detailed review of the overall s ituation of genetic engineering, especially the development and commer cialization planting of GM crops, massive volume imports of GM crops, their management, liabilities and consequences showing up in China.

The Safety Management & Liability on GMO Products in China

Chen I-wan 원광대학교 법학연구소 2010 의생명과학과 법 Vol.4 No.-

System-level Performance Evaluation of eICIC Scheme in 3GPP LTE-Advanced HetNet

Wan Chen,KyungHi Chang 한국통신학회 2016 한국통신학회 학술대회논문집 Vol.2016 No.1

With the deployment of heterogeneous network (HetNet), time-domain interference coordination technology using Almost Blank Subframes (ABS) has been widely considered as a promising solution for interference elimination between macro cells and small cells. In this paper, the enhanced inter-cell interference coordination (eICIC) technique is briefly introduced and the system level performance is evaluated comparing the cases with and without eICIC. In addition, the system throughput with various configurations of ABS ratio is also presented to observe the fixed ABS ratio could not support the scenario of the next generation (5G) mobile communication systems which has the dynamically changing requirements of users. Configuring high ABS ratio for limited traffic demand from cell edge UEs may result in throughput loss.

Differentiation of embryonic stem cells into cardiomyocytes in a compliant microfluidic system.

Wan, Chen-rei,Chung, Seok,Kamm, Roger D Pergamon Press [etc.] 2011 Annals of biomedical engineering Vol.39 No.6

<P>The differentiation process of murine embryonic stem cells into cardiomyocytes was investigated with a compliant microfluidic platform which allows for versatile cell seeding arrangements, optical observation access, long-term cell viability, and programmable uniaxial cyclic stretch. Specifically, two environmental cues were examined with this platform--culture dimensions and uniaxial cyclic stretch. First, the cardiomyogenic differentiation process, assessed by a GFP reporter driven by the α-MHC promoter, was enhanced in microfluidic devices (?FDs) compared with conventional well-plates. The addition of BMP-2 neutralizing antibody reduced the enhancement observed in the ?FDs and the addition of exogenous BMP-2 augmented the cardiomyogenic differentiation in well plates. Second, 24 h of uniaxial cyclic stretch at 1 Hz and 10% strain on day 9 of differentiation was found to have a negative impact on cardiomyogenic differentiation. This microfluidic platform builds upon an existing design and extends its capability to test cellular responses to mechanical strain. It provides capabilities not found in other systems for studying differentiation, such as seeding embryoid bodies in 2D or 3D in combination with cyclic strain. This study demonstrates that the microfluidic system contributes to enhanced cardiomyogenic differentiation and may be a superior platform compared with conventional well plates. In addition to studying the effect of cyclic stretch on cardiomyogenic differentiation, this compliant platform can also be applied to investigate other biological mechanisms.</P>