Structural Basis of Emi2 Recognition by Polo-Box Domain of Polo-like Kinase 1 and Effects of Structure-Derived Antagonist in Oocyte Maturation and Fertillization

Jia-Jia Lin,Young-Hyun Han,Jung-Woo Kwon,Yong-Nan Xu,Yi-Bo Luo,Yu-Jin Jo,Chang-Eun Park,Jung-Kyu Baang,Suk Namgoong,Nam-Hyung Kim 한국동물생명공학회(구 한국동물번식학회) 2014 Reproductive & Developmental Biology(Supplement) Vol.38 No.2s

In meiosis, Emi2 plays important role as CSF (Cytostatic Factor) to make the oocyte arrested in mII stage by the inhibition of APC/C (anaphase promoting complex/cyclosome). Once the oocyte fertilized, Emi2 was destabilized and degraded. For the degradation of Emi2, calcium signaling activate calmodulin-dependent protein kinase (CaMK) and phosphorylate emi2. Phosphorylated emi2 is recognized by polo-box domain of polo-like kinase 1 (Plk1) and further degradated by ubiquitin-dependent proteolysis. But recognition of Plk1 and emi2 is unknown. In this works, we determined the high-resolution crystal structure of polo-box domain of Plk1 and phosphorylated emi2 peptide at 1.90Å. Determined structure revealed that several unique features, including binding of Phe169 in the tyrosin-rich hydrophobic pocket. This is the first report of crystallization that Plk1-emi2 complex. Based on the complex structure, we designed the peptide analogs which pontentially inhibits recognition of Emi2 by Plk1 and assessed its biological activity in oocyte maturation and pathernogenetic activation. Injection of AB103-8, the inhibitor of Plk1 Polo-box domain, in mouse oocytes, induced the maturation arrest in GV stage and the delay in mII parthenogenetic activation. Further investigations of the mechanism that Plk1 involved into the Emi2 mII arrest are underway.

Protect User’s Privacy in Location-based Service Queries

Jia-Ning Luo,Ming-Hour Yang,Kuo-Yu Tsai 한국정보기술학회 2017 Proceedings of The International Workshop on Futur Vol.2017 No.7

Branched polymeric prodrug/programmed cell death 4 complexes for combinational cancer therapy

Yu‑Jing He,Lei Xing,Peng‑Fei Cui,Jia‑Liang Zhang,Jian‑Bin Qiao,Cheng‑Qiong Luo,Ge Jiang,Hu‑Lin Jiang 한국약제학회 2017 Journal of Pharmaceutical Investigation Vol.47 No.2

Here, we demonstrate a co-delivery system constructed by integrating chemotherapeutic molecules into branched polymeric prodrug which can condense nucleic acids. Demethylcantharidate (DCA) was chosen as a model drug and premodified through nucleophilic substitution reaction by its two carboxylic groups with allyl chloride. The synthesized intermediate (DCA-dially) was then used to polymerize with tris (2-aminoethyl) amine (TAEA) through progressively ammonolysis reaction. The obtained poly (DCA-alt-TAEA) (DCAT) was used to pack PDCD4 into spherical-like nanoparticles through electrostatic interaction. Gel retardation assays implied that DCAT could integrate DNA at the weight ratio of 1 and protect it from digestion by nuclease. Acid-base titration experiments showed that DCAT obtained preferable buffering capability which was beneficial for the endosomal escape of DCAT/PDCD4 complexes. Cellular tests involving gene transfection efficiency and cytotoxicity indicated that DCA and PDCD4 co-delivered by the complexes significantly and synergistically suppressed the viability of SMMC-7721 cells. These results suggest that integrating chemotherapeutic molecules into nucleic acid-packing polymeric prodrug as cationic polymer/PDCD4 complexes is a highly efficient way to co-deliver chemotherapeutic drugs and nucleic acids for cancer therapy.

Experimental Study on Chloride Diffusion in Structural Concrete Considering the Effect of Damages Induced by the Cyclic Impact Loading

Peng-yu Zhu,Yong-lai Zheng,Wen-bin Luo,Jia Kou,Ru-xue Zhang,Shu-xin Deng 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.1

An experimental investigation on chloride diffusion in structural concrete under the cyclic impact loading is conducted. Effects of magnitudes and loading times are studied. Relationship between damage coefficients and chloride diffusion coefficients is obtained. The cyclic impact loading causes the initiation of new cracks and the propagation of existing cracks, which brings an obvious promotion for chloride diffusion. There should be a damage threshold. If the magnitude of the external loading is large enough to make the damage exceed the threshold, initiation and propagation of cracks become quite significant and chloride diffusion can be greatly promoted. With the increase of the damage coefficient, the chloride diffusion coefficient increases. The increasing rates decrease with long immersion times. Relationship curves of damage coefficients and chloride diffusion coefficients show a good correlation and can be well described with power functions.

A New Analytical Method for Link Slab Analysis

Yufan Luo,Quansheng Yan,Xiaogang Yue,Buyu Jia,Xiaolin Yu,Yuxuan Chen 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.2

Link slabs have been widely used to reduce the number of expansion joints. However, traditional reinforced concrete link slabs are prone to cracking issues, making it crucial to accurately calculate their internal forces. Currently, the most advanced link slab analysis methods treat the link slab and adjacent span as a rotational spring to simulate their restriction on the girder end rotation. However, this method does not comprehensively consider the link slab's influence, leading to conservative results. To address this issue, this study further considers the influence of girder end deformations on adjacent span, resulting in more accurate calculations of the link slab's internal forces. Additionally, the concept of the girder end rotation reduction coefficient is put forward for the first time, which provides a clearer and more quantified understanding of the link slab's influence. The proposed method is verified by a model test and a site test, which shows a significant improvement in accuracy compared to existing analytical methods. On this basis, a parametric study is conducted to investigate the influence of various parameters on the girder end rotation reduction coefficient, which indicates that span length, girder spacing, and support configuration have the greatest influence.

End Plate–Stiff ener Connection for SHS Column and RHS Beam in Steel-Framed Building Modules

Fu Jia Luo,Chenting Ding,Adam Styles,Yu Bai 한국강구조학회 2019 International Journal of Steel Structures Vol.19 No.4

This paper investigates the mechanical performance of beam-to-column connections for steel-framed building modules with RHS and SHS sections of relatively small member sizes. In the experimental program, three forms of connections are tested under static bending, including a completely welded connection (W), a bolted end plate connection (EP) and the proposed end plate–stiff ener connection (ST), and the failure modes, moment–rotation behaviours and strain responses were recorded during experiments. Results show that ST connection exhibited superior connection strength, stiff ness and ductility compared with the EP connection. In addition, a detailed fi nite element analysis was conducted to model the connection behaviours, considering bolt pretension, contact behaviours and detailed bolt geometry, showing good comparison with experiments. Furthermore, a parametric study was performed on the end plate thickness and stiff ener thickness for the proposed end plate–stiff ener connection. Such results fi nally enable a comparative study to investigate the performance of module during road transportation, highlighting the eff ects of connection stiff ness.

Enantioselective Synthesis of <i>anti</i>–<i>syn</i>-Trihalides and <i>anti</i>–<i>syn</i>–<i>anti</i>-Tetrahalides via Asymmetric β-Elimination

Tan, Yu,Luo, Shilong,Li, Dongmei,Zhang, Nan,Jia, Shiqi,Liu, Yidong,Qin, Wenling,Song, Choong Eui,Yan, Hailong American Chemical Society 2017 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.139 No.18

<P>Structural motifs containing contiguous halide bearing stereocenters are common in natural products as well as bioactive molecules. A few successful examples have been reported in the area of asymmetric vicinal dihalogenation of alkenes for accessing dihalogenated products; in this report, an alternative generation method of contiguous halide-bearing stereocenters alpha,beta,gamma,delta relative to carbonyl group in excellent enantioselectivity is proposed by utilizing a Song's oligoEG catalyst-catalyzed asymmetric beta-elimination. According to this methodology, a wide range of anti-syn-trihalides and anti-syn-anti-tetrahalides with high levels of enantioselectivity were synthesized. The synthetic utility of the contiguous halide-bearing stereocenters was demonstrated by several transformations. The results of high-resolution mass spectrometry indicated that the favorable interaction between catalyst and one of the enantiomers of racemic contiguously multihalogenated ketone contributed to the original enantioselectivity of dehydrohalogenation. A deuterium kinetic isotope effect experiment revealed that this beta-elimination reaction proceeds by the E2 mechanism. This strategy opens a new pathway for the asymmetric synthesis of contiguous halide bearing stereocenters of great complexity.</P>

Laccase-Mediated In Situ Oxidation of Dopamine for Dyeing of Human Hair

Weini Jia,Shirong Li,Zhengxin Luo,Hainan Yu,Wenjun Zhu,Wenjun Zhu,Qing-hui Mao,Xiaoli Zhang,Zhi-jie Liang,Aixue Dong 한국섬유공학회 2021 Fibers and polymers Vol.22 No.1

Due to the damage of scalp because of chemical dyes, increasing attention had been paid to the ecological dyeingof human hair. To address the need for ecological restoration and dyeing of human hair, herein, a novel approach has beenproposed via laccase-mediated in situ oxidation of dihydroxy phenylalanine (dopamine). As laccase can catalyze dopamineoxidation and then polymerization to produce strongly colored polymers, different biological coloration processes of humanhair based on this process were investigated: (i) Human hair was treated with laccase alone; (ii) The absorption of human hairwith dopamine, followed by further catalysis of air; (iii) The absorption of human hair with dopamine, followed by furthercatalysis of laccase; (iv) Simultaneous laccase-mediated polymerization and dyeing of human hair; and (v) Polymerization ofDopamine with laccase and then dyeing human hair. The surface properties of dyed hair were evaluated in terms of ultraviolet(UV)-protection, color fastness, Fourier transforming infrared spectrum (FT-IR), optical microscope, and scanning electronmicroscopy (SEM). The results show that best hair dyeing effect was achieved via simultaneous laccase-mediatedpolymerization and dyeing. The dyed hair obtained K/S values of 28, light fastness of level 5, and UPF of 100+. The opticalmicroscope and SEM observations show that the surface of colored hair fibers was covered with thin burrs, which can beattributed to polydopamine attached with physical adhesive force and covalent reaction. FT-IR analysis shows that functionalgroups were present on the surface of the dyed hair which can be considered as introduction of hydroxyl radical groups. Thisbiological stain technique may be widely used in dyeing of hair with black color.

Heat Treatment Influence on Tribological Properties of AlCoCrCuFeNi High‑Entropy Alloy in Hydrogen Peroxide‑Solution

X. S. Luo,J. Li,Y. L. Jin,C. P. Hu,D. Jia,S. P. Zhan,Y. Yu,M. Hua,H. T. Duan 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.8

Tribological properties of AlCoCrCuFeNi high-entropy alloy were studied after annealing at various temperatures. X-raydiffraction, scanning electron microscopy, energy dispersive spectroscopy, microhardness tester and pin-on-disc tribometeranalyses were performed to reveal the microstructure, composition, microhardness and tribological behavior variations. Withthe heat treatment temperature increasing, time taken for friction coefficient going through the rapidly dropping down andthen into the stable period increases, the white sheets structures and their size in dendrite area of the AlCoCrCuFeNi alloybecomes bigger, however BCC content declined dramatically. Then, the average friction coefficient of the AlCoCrCuFeNi/Si3N4 sliding friction pair increase from 0.037 to 0.115, and the pin wear loss increase from 3 to 11 μm.

Prevalence and Genotype Distribution of Human Papillomavirus Infections in Women Attending Hospitals in Chaozhou of Guangdong Province

Chen, Qiang,Luo, Zhao-Yun,Lin, Min,Lin, Qi-Li,Chen, Chan-Yu,Yang, Chun,Xie, Long-Xu,Li, Hui,Zheng, Jia-Kun,Yang, Li-Ye,Ju, Gui-Zhi Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.4

Background: Human papillomavirus (HPV) infection is the main cause of cervical cancer. Limited epidemiologic data of HPV prevalence are available for women attending hospitals in southern China. This study aimed to evaluate the profiles of HPV infection and cytology status in gynecological outpatients in Chaozhou City. Methods: A total of 2833 eligible women were enrolled. The HPV GenoArray test was used for HPV detection and genotyping. Nearly one half of the HPV positive women received liquid-based cytology test. Logistic regression analysis was performed to assess the predictable effects of age and genotype for categories of abnormal cytology. Results: The prevalence of overall, high-risk, and low-risk HPV infection were 24.5%, 19.5% and 8.4%, respectively. A U-shaped age-specific prevalence curve was observed in overall HPV and high-risk HPV, but not in low-risk HPV, which declined with age increasing. The 6 most common high-risk HPV type in descending order, were types 52, 16, 58, 18, 68, and 33. Age and HPV genotype were both important determinants of abnormal cytology incidence, the older women (>45 years) and those infected with HPV type 16 and/or 18 having the highest risk for abnormal cytology. Conclusion: Our findings support the hypothesis that second-generation HPV prophylactic vaccines including HPV-52 and -58 may offer higher protection for women residing in Chaozhou and neighboring cities in Guangdong.