Chemically Modified Sepharose as Support for the Immobilization of Cholesterol Oxidase

( Hai Lin Yang ),( Yi Chen ),( Yu Xin ),( Ling Zhang ),( Yu Ran Zhang ),( Wu Wang ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.9

Because the cholesterol oxidase from Brevibacterium sp. M201008 was not as stable as the free enzyme form, it had been covalently immobilized onto chemically modified Sepharose particles via N-ethyl-N`-3-dimethylaminopropyl carbodiimide. The optimum immobilization conditions were determined, and the immobilized enzyme activity obtained was 12.01 U/g Sepharose-ethylenediamine. The immobilization of the enzyme was characterized by Fourier transform infrared spectroscopy. The immobilized enzyme exhibited the maximal activity at 35oC and pH 7.5, which was unchanged compared with the free form. After being repeatedly used 20 times, the immobilized enzyme retained more than 40.43% of its original activity. The immobilized enzyme showed better operational stability, including wider thermal and pH ranges, and retained 62.87% activity after 20 days of storage at 4oC, which was longer than the free enzyme.

Dynamics of rate of returns for postgraduate education in Taiwan: the impact of higher education expansion

Chih-Hai Yang,Chun-Hung A. Lin,Chien-Ru Lin 서울대학교 교육연구소 2011 Asia Pacific Education Review Vol.12 No.3

This paper analyzes the dynamics of rate of returns for postgraduate education and the determinants of wage premiums for postgraduate labor, especially for the impact of higher education expansions, in terms of quantity and quality, since the late 1990s in Taiwan. Utilizing quasi-panel data over the 1990-2004 period and employing the double fixed effect model, the empirical results first confirm the existence of wage premiums for workers with postgraduate degrees. However, the analysis on the dynamics of wage premiums finds that it ranged from only 1.40 to 11.67% and decreased sharply in 2004, indicating that the pecuniary reward for postgraduate qualification seems not to be as high as expected. Along with the rapid expansion of higher education, the concern about its negative impact on rate of returns to education is witnessed in this study. The sharp increase in the supply of postgraduate labors appears to have a negative impact on an individual's wage premium. Similarly, a decline in the postgraduate labor quality along with higher education expansion has contributed to a negative wage effect.

The Expression of Carnosine and Its Effect on the Antioxidant Capacity of Longissimus dorsi Muscle in Finishing Pigs Exposed to Constant Heat Stress

Yang, Peige,Hao, Yue,Feng, Jinghai,Lin, Hai,Feng, Yuejin,Wu, Xin,Yang, Xin,Gu, Xianhong Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.12

The objective of this study was to assess the effects of constant high ambient temperatures on meat quality, antioxidant capacity, and carnosine expression in longissimus dorsi muscle of finishing pigs. Castrated 24 male DLY (crossbreeds between Landrace${\times}$Yorkshire sows and Duroc boars) pigs were allocated to one of three treatments: constant ambient temperature at $22^{\circ}C$ and ad libitum feeding (CON, n = 8); constant high ambient temperature at $30^{\circ}C$ and ad libitum feeding (H30, n = 8); and constant ambient temperature at $22^{\circ}C$ and pair-fed with H30 (PF, n = 8). Meat quality, malondialdehyde (MDA) content, antioxidant capacity, carnosine content, and carnosine synthetase (CARNS1) mRNA expression in longissimus dorsi muscle were measured after three weeks. The results revealed that H30 had lower $pH_{24h}$, redness at 45 min, and yellowness at 24 h post-mortem (p<0.05), and higher drip loss at 48 h and lightness at 24 h post-mortem (p<0.01). Constant heat stress disrupted the pro-oxidant/antioxidant balance in longissimus dorsi muscle with higher MDA content (p<0.01) and lower antioxidant capacity (p<0.01). Carnosine content and CARNS1 mRNA expression in longissimus dorsi muscle of H30 pigs were significantly decreased (p<0.01) after three weeks at $30^{\circ}C$. In conclusion, constant high ambient temperatures affect meat quality and antioxidant capacity negatively, and the reduction of muscle carnosine content is one of the probable reasons.

Pure choriocarcinoma of the ovary: a case report

Lin Lv,Kalxuan Yang,Jiangyan Lou,Zhilan Peng,Hai Wu 대한부인종양학회 2011 Journal of Gynecologic Oncology Vol.22 No.2

Pure ovarian choriocarcinomas are extremely rare and aggressive tumors which are gestational or non-gestational in origin. Due to the rarity of the tumor, there is a lack of information on the clinicopathologic features, diagnosis, and treatment. We report a case of a pure ovarian choriocarcinoma, likely of non-gestational origin, treated by cytoreductive surgery in combination with post-operative chemotherapy. The patient was free of disease after a 12-month follow-up.

Development of Integrated Multi-Station System to Precisely Detect and Mitigate Surface Damage on Fused Silica Optics

Lin-Jie Zhao,Jian Cheng,Ming-Jun Chen,Xiao-Dong Yuan,Wei Liao,Hao Yang,Qi Liu,Hai-Jun Wang 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.22 No.1

In high power laser facility, irreversible damage on fused silica optics, induced by laser irradiation or processing, seriously affects the service life of optics. Therefore, the work of inhibiting damage growth has been carried out in various countries. In our work, an integrated multi-station system is designed to detect and mitigate surface damage on fused silica. The process of processing fused silica optics include UV laser conditioning, surface damage detection and surface damage mitigation with CO2 laser. UV laser conditioning pre-initiates surface damage on fused silica optics with the laser flux less than Laser-Induced Damage Threshold (LIDT). Images of surface damage acquired from camera are processed by improved global threshold segmentation algorithm to extract damage information. Finally, CO2 laser is applied to process the damage with specific morphology to enhance the laser damage resistance. This integrated multi-station system saves the repeated optics installation time between the workstations with the positioning accuracy of 20 μm. Furthermore, the damage with diameter of 10 μm is mitigated to prolong service life of processed fused silica optics. The efficient and accurate integrated multi-station system is of great significance for off -line detecting and mitigating surface damage of fused silica optics in high power laser facility.

IL-33 promotes IL-10 production in macrophages: a role for IL-33 in macrophage foam cell formation

Hai-Feng Zhang,Mao-Xiong Wu,Yong-Qing Lin,Shuang-Lun Xie,Tu-Cheng Huang,Pin-Ming Liu,Ru-Qiong Nie,Qin-Qi Meng,Nian-Sang Luo,Yang-Xin Chen,Jing-Feng Wang 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

We evaluated the role of IL-10- in IL-33-mediated cholesterol reduction in macrophage-derived foam cells (MFCs) and the mechanism by which IL-33 upregulates IL-10. Serum IL-33 and IL-10 levels in coronary artery disease patients were measured. The effects of IL-33 on intra-MFC cholesterol level, IL-10, ABCA1 and CD36 expression, ERK 1/2, Sp1, STAT3 and STAT4 activation, and IL-10 promoter activity were determined. Core sequences were identified using bioinformatic analysis and sitespecific mutagenesis. The serum IL-33 levels positively correlated with those of IL-10. IL-33 decreased cellular cholesterol level and upregulated IL-10 and ABCA1 but had no effect on CD36 expression. siRNA-IL-10 partially abolished cellular cholesterol reduction and ABCA1 elevation by IL-33 but did not reverse the decreased CD36 levels. IL-33 increased IL-10 mRNA production but had little effect on its stability. IL-33 induced ERK 1/2 phosphorylation and increased the luciferase expression driven by the IL-10 promoter, with the highest extent within the − 2000 to − 1752 bp segment of the 5′-flank of the transcription start site; these effects were counteracted by U0126. IL-33 activated Sp1, STAT3 and STAT4, but only the STAT3 binding site was predicted in the above segment. Site-directed mutagenesis of the predicted STAT3-binding sites (CTGCTTCCTGGCAGCAGAA→CTGCCTGGCAGCAGAA) reduced luciferase activity, and a STAT3 inhibitor blocked the regulatory effects of IL-33 on IL-10 expression. Chromatin immunoprecipitation (CHIP) confirmed the STAT3-binding sequences within the − 1997 to − 1700 and − 1091 to − 811 bp locus regions. IL-33 increased IL-10 expression in MFCs via activating ERK 1/2 and STAT3, which subsequently promoted IL-10 transcription and thus contributed to the beneficial effects of IL-33 on MFCs.

Comparison of the Efficacy and Prognostic Factors of Transarterial Chemoembolization Plus Microwave Ablation versus Transarterial Chemoembolization Alone in Patients with a Large Solitary or Multinodular Hepatocellular Carcinomas

Lin Zheng,Hai-Liang Li,Chen-Yang Guo,Su-Xia Luo 대한영상의학회 2018 Korean Journal of Radiology Vol.19 No.2

Objective: To evaluate the efficacy and prognostic factors associated with transcatheter arterial chemoembolization (TACE) combined with microwave ablation (MWA) versus TACE alone for a large solitary or multinodular hepatocellular carcinomas (HCCs). Materials and Methods: This retrospective study involved 258 patients with a large solitary or multinodular HCCs (not more than 10 tumors) who underwent TACE + MWA (n = 92) or TACE alone (n = 166) between July 2011 and April 2015. Local tumor control, survival outcomes, and complications were compared between the two groups. Prognostic factors for time to progression (TTP) and overall survival (OS) were evaluated by univariate and multivariate analyses. Results: The median duration of follow-up was 21.2 months (range, 4−45 months). The median TTP and OS were 12.5 months and 26.6 months, respectively, for the TACE + MWA group and 6.7 months and 17.1 months, respectively, for the TACE group (p < 0.001). The 1-, 2-, and 3-year OS rates were 85.9, 59.8, and 32.6%, respectively, for the TACE + MWA group and 59.0, 40.4, and 11.4%, respectively, for the TACE group (p < 0.001). The corresponding recurrence rates were 47.8, 78.3, and 94.6% for the TACE + MWA group, respectively, and 74.7, 96.4, and 97.6%, respectively, for the TACE group (p < 0.001). Logistic regression analyses showed that the treatment method, tumor size, and tumor number were significant prognostic factors for TTP and OS. Conclusion: TACE + MWA appears to have more advantages compared to TACE in prolonging OS, with a satisfactory TTP, for inpatients with solitary large or multinodular HCCs. Treatment method, tumor size, and tumor number are significant prognostic factors for TTP and OS. Further randomized, multi-center, prospective trials are required to confirm the findings of this study.

Induction Chemotherapy Plus Concurrent Chemoradiotherapy versus Concurrent Chemoradiotherapy Alone in Locoregionally Advanced Nasopharyngeal Carcinoma in Children and Adolescents: A Matched Cohort Analysis

Yang Li,Lin-Quan Tang,Li-Ting Liu,Shan-Shan Guo,Yu-Jing Liang,Xue-Song Sun,Qing-Nan Tang,Jin-Xin Bei,Jing Tan,Shuai Chen,Jun Ma,Chong Zhao,Qiu-Yan Chen,Hai-Qiang Mai 대한암학회 2018 Cancer Research and Treatment Vol.50 No.4

Purpose The purpose of this study was to evaluate the long-term clinical outcome and toxicity of induction chemotherapy (IC) followed by concomitant chemoradiotherapy (CCRT) compared with CCRT alone for the treatment of children and adolescent locoregionally advanced nasopharyngeal carcinoma (LACANPC). Materials and Methods A total of 194 locoregionally advanced nasopharyngeal carcinoma patients younger than 21 years who received CCRT with or without IC before were included in the study population. Overall survival (OS) rate, progression-free survival (PFS) rate, locoregional recurrence-free survival (LRFS) rate, and distant metastasis-free survival (DMFS) rate were assessed by the Kaplan-Meier method and a log-rank test. Treatment toxicities were clarified and compared between two groups. Results One hundred and thiry of 194 patients received IC+CCRT. Patients who were younger and with more advanced TNM stage were more likely to receive IC+CCRT and intensive modulated radiotherapy. The addition of IC before CCRT failed to improve survival significantly. The matched analysis identified 43 well-balanced patients in both two groups. With a median follow-up of 51.5 months, no differences were found between the IC+CCRT group and the CCRT group in 5-year OS (83.7% vs. 74.6%, p=0.153), PFS (79.2% vs. 73.4%, p=0.355), LRFS (97.7% vs. 88.2%, p=0.083), and DMFS (81.6% vs. 81.6%, p=0.860). N3 was an independent prognostic factor predicting poorer OS, PFS, and DMFS. The addition of IC was associated with increased rates of grade 3 to 4 neutropenia. Conclusion This study failed to demonstrate that adding IC before CCRT could provide a significant additional survival benefit for LACANPC patients. Further investigations are warranted.

A Newly Synthesized Flavone from Luteolin Escapes from COMT-Catalyzed Methylation and Inhibits Lipopolysaccharide-Induced Inflammation in RAW264.7 Macrophages via JNK, p38 and NF-κB Signaling Pathways

( Lin Ye ),( Yang Xin ),( Zhi-yuan Wu ),( Hai-jian Sun ),( De-jian Huang ),( Zhi-qin Sun ) 한국미생물 · 생명공학회 2022 Journal of microbiology and biotechnology Vol.32 No.1

Luteolin is a common dietary flavone possessing potent anti-inflammatory activities. However, when administrated in vivo, luteolin becomes methylated by catechol-O-methyltransferases (COMT) owing to the catechol ring in the chemical structure, which largely diminishes its anti-inflammatory effect. In this study, we made a modification on luteolin, named LUA, which was generated by the chemical reaction between luteolin and 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH). Without a catechol ring in the chemical structure, this new flavone could escape from the COMT-catalyzed methylation, thus affording the potential to exert its functions in the original form when administrated in the organism. Moreover, an LPS-stimulated RAW cell model was applied to detect the anti-inflammatory properties. LUA showed much more superior inhibitory effect on LPS-induced production of NO than diosmetin (a major methylated form of luteolin) and significantly suppressed upregulation of iNOS and COX-2 in macrophages. LUA treatment dramatically reduced LPS-stimulated reactive oxygen species (ROS) and mRNA levels of pro-inflammatory mediators such as IL-1β, IL-6, IL-8 and IFN-β. Furthermore, LUA significantly reduced the phosphorylation of JNK and p38 without affecting that of ERK. LUA also inhibited the activation of NF-κB through suppression of p65 phosphorylation and nuclear translocation.

A Functional SNP in the MDM2 Promoter Mediates E2F1 Affinity to Modulate Cyclin D1 Expression in Tumor Cell Proliferation

Yang, Zhen-Hai,Zhou, Chun-Lin,Zhu, Hong,Li, Jiu-Hong,He, Chun-Di Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.8

Background: The MDM2 oncogene, a negative regulator of p53, has a functional polymorphism in the promoter region (SNP309) that is associated with multiple kinds of cancers including non-melanoma skin cancer. SNP309 has been shown to associate with accelerated tumor formation by increasing the affinity of the transcriptional activator Sp1. It remains unknown whether there are other factors involved in the regulation of MDM2 transcription through a trans-regulatory mechanism. Methods: In this study, SNP309 was verified to be associated with overexpression of MDM2 in tumor cells. Bioinformatics predicts that the T to G substitution at SNP309 generates a stronger E2F1 binding site, which was confirmed by ChIP and luciferase assays. Results: E2F1 knockdown downregulates the expression of MDM2, which confirms that E2F1 is a functional upstream regulator. Furthermore, tumor cells with the GG genotype exhibited a higher proliferation rate than TT, correlating with cyclin D1 expression. E2F1 depletion significantly inhibits the proliferation capacity and downregulates cyclin D1 expression, especially in GG genotype skin fibroblasts. Notably, E2F1 siRNA effects could be rescued by cyclin D1 overexpression. Conclusion: Taken together, a novel modulator E2F1 was identified as regulating MDM2 expression dependent on SNP309 and further mediates cyclin D1 expression and tumor cell proliferation. E2F1 might act as an important factor for SNP309 serving as a rate-limiting event in carcinogenesis.