E ffects of exogenous spermidine and spermine on antioxidant metabolism associated with cold-induced leaf senescence in Zoysiagrass (Zoysia japonica Steud.)

Xinbo Sun,Lijuan Xie,Liebao Han 한국원예학회 2019 Horticulture, Environment, and Biotechnology Vol.60 No.3

Zoysiagrass ( Zoysia japonica Steud.) leaves lose their green colour as they undergo cold acclimation (CA) in late fall inmany regions, and delaying leaf senescence can extend their green period. The objective of this study was to investigatewhether exogenous spermidine (Spd) and spermine (Spm) can delay leaf senescence by enhancing reactive oxygen species(ROS)-scavenging antioxidant enzyme activity. Mature zoysiagrass (cv. Zenith) plants were treated with Spm (1 mM) or Spd(1 mM) or water (control). The treated plants were grown under normal conditions or subjected to cold acclimation CA for35 days. CA treatment increased leaf electrolyte leakage (EL) and malondialdehyde (MDA) level, decreased chlorophyll (Chl)content, and induced leaf senescence. Foliar application of Spd and Spm reduced the decline in Chl content and reduced ELand MDA levels. CA treatment increased the ROS level and reduced antioxidant enzyme activity. Application of Spm andSpd reduced ROS accumulation and enhanced the activities of superoxide dismutase, peroxidase, catalase, and ascorbateperoxidase under CA conditions. The results of this study indicated that exogenous Spd and Spm at 1 mM can delay CAinducedleaf senescence through enhancement of ROS-scavenging antioxidant activity in zoysiagrass.

The Secure IEEE 11073:20601 Protocol and Agent Structure for Protecting PHD

Xiaolong Xu,Zhonghe Gao,Lijuan Han 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.12

In this paper, we suggest improvements of security in IEEE 11073:20601 protocol and the structure of its agent for protecting user’s healthcare information safely. Current IEEE 11073:20601 standard does not provide any method to ensure security of data exchange, and it assumes that data exchange is secured by other means. The suggested improvements include mechanism to enhance security in exchanging and storing data in PHD. While providing those advantages, it also satisfies availability by effective encoding rules and data protecting algorithm.

Effect of localized reduction of gibberellins in different tobacco organs on drought stress tolerance and recovery

Tianxiu Zhong,Huiming Zeng,Liebao Han,Lijuan Zhang,Shanshan Sun 한국식물생명공학회 2014 Plant biotechnology reports Vol.8 No.5

Drought resistance is increased in plants by theabsence of the hormone gibberellic acid (GA) or by a lackof GA sensitivity. We studied the effects of tissue-specificreduction in GA levels on drought tolerance, on recoveryfrom drought stress, and on primary and secondary growthusing transgenic tobacco plants expressing the GA-inactivatinggene PtGA2ox1 (GA 2-oxidase) specifically inleaves, stems, or roots. Localized reduction of bioactiveGA1 levels was achieved by tissue-specific expression ofthe PtGA2ox1 gene in leaves using the rbcs promoter (LDplants), in roots using the TobRB7 promoter (RD plants),and in stems using the LMX5 promoter (SD plants). Inresponse to drought stress, all transgenic tobacco plantsexhibited reduced primary and secondary growth andincreased drought tolerance with a corresponding reductionin malondialdehyde levels, higher relative water content,increased proline and sugar content, and elevated peroxidase,superoxide dismutase, and catalase activities relativeto wild-type plants. The highest level of drought toleranceand the most rapid recovery from stress was achieved bylocalized reduction of GA1 in the roots of the RD transgenicplants. In addition, although the total bioactive GA1content in RD and LD plants was essentially identical, theheights of LD plants were significantly greater and droughttolerance was significantly less than in RD plants. It ispossible that the site of gibberellin-related gene expressionplays an important role in the balance between growth anddrought tolerance.

Assessment of clinical competency among TCM medical students using standardized patients of traditional Chinese medicine: A 5-year prospective randomized study

Zeng Jinhao,Liang Shuang,Zhang Xiaotong,Yan Ran,Chen Chongli,Wen Lijuan,Xia Ting,Li Wenyuan,Lu Bingqing,Nian Qing,Yang Han,Guo Jing 한국한의학연구원 2022 Integrative Medicine Research Vol.11 No.2

Background: Some Western medicine schools in China established standardized patient (SP) programs for medical education. However, SP programs are rarely applied to the education of traditional Chinese medicine (TCM). In this study, we evaluated the effectiveness of using standardized patient traditional Chinese medicine (SP-TCM) to improve clinical competency among TCM medical students. Methods: This study was a prospective, 2-group, parallel-training randomized trial over the course of 5 years. Data were collected from September 2016 to December 2020. Participants in each year were randomly allocated into the traditional-method training group or the SP-TCM training group (1:1) for a 3-month curriculum. Measurement of clinical competency among all trainees was based on a standardized examination composed of scores of medical record documentation, scores of TCM syndrome differentiation and therapeutic regimen, and checklist assessment from both SP-TCMs and TCM professionals. Feedback was collected using semi-constructive questionnaires from both groups. Results: Compared with those assigned to traditional-method training, those assigned to SP-TCM training demonstrated significantly greater post-training improvement in medical record documentation and TCM syndrome differentiation and therapeutic regimen. Moreover, SP-TCM trainees outscored those assigned to traditional training in the assessment for encounter performance given by independent SP-TCMs and TCM professionals. The SP-TCM method gained higher satisfaction of training efficacy and test performance than the traditional method. Conclusion: This SP-TCM program demonstrated great benefits for improving clinical competency among TCM medical students.

Heterologous Expression and Characterization of a Laccase from Laccaria bicolor in Pichia pastoris and Arabidopsis thaliana

( Bo Wang ),( Ying Yan ),( Jing Xu ),( Xiaoyan Fu ),( Hongjuan Han ),( Jianjie Gao ),( Zhenjun Li ),( Lijuan Wang ),( Yongsheng Tian ),( Rihe Peng ),( Quanhong Yao ) 한국미생물 · 생명공학회 2018 Journal of microbiology and biotechnology Vol.28 No.12

Laccases can oxidize a variety of phenolic and non-phenolic substrates including synthetic dyes. In this research, a laccase gene Lcc9 from Laccaria bicolor was chemically synthesized and optimized to heterogeneous expression in Pichia pastoris and Arabidopsis thaliana. The properties of recombinant laccase expressed by P. pastoris were investigated. The laccase activity was optimal at 3.6 pH and 40°C. It exhibited K_m and V_max values of 0.565 mmol l^-1 and 1.51 μmol l^-1 min^-1 for ABTS respectively. As compared with untransformed control plants, the laccase activity in crude extracts of transgenic lines exhibited a 5.4 to 12.4-fold increase. Both laccases expressed in transgenic P. pastoris or A. thaliana could decolorize crystal violet. These results indicated that L. bicolor laccase gene may be transgenically exploited in fungi or plants for dye decolorization.

Nonenzymatic Electrochemical Immunosensor Using Ferroferric Oxide–Manganese Dioxide–Reduced Graphene Oxide Nanocomposite as Label for α-Fetoprotein Detection

Wensi Jian,Chunping Wang,Zuanguang Chen,Yanyan Yu,Duanping Sun,Liping Han,Lijuan Shi 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2016 NANO Vol.11 No.10

A novel nonenzymatic electrochemical immunosensor was fabricated for quantitative detection of α-fetoprotein (AFP). The immunosensor was constructed by modifying gold electrode with electrochemical reduction of graphene oxide-carboxyl multi-walled carbon nanotube composites (ERGO–CMWCNTs) and electrodeposition of gold nanoparticles (AuNPs) for effective immobilization of primary antibody (Ab1). Ferroferric oxide–manganese dioxide–reduced graphene oxide nanocomposites (Fe3O4@MnO2–rGO) were designed as labels for signal amplification. On one hand, the excellent electroconductivity and outstanding electron transfer capability of ERGO–CMWCNTs/AuNPs improved the sensitivity of the immunosensor. On the other hand, introduction of rGO could not only increase the specific surface area for immobilization of secondary antibody (Ab2) but also build a synergetic effect to reinforce the electrocatalytic properties of catalysts. Fe3O4@MnO2–rGO nanocomposites were characterized by scanning electron microscope, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Using AFP as a model analyte, the proposed sandwich-type electrochemical immunosensor exhibited a wide linear range of 0.01–50 ng · mL-1 with a low detection limit of 5.8 pg · mL-1. Moreover, the Fe3O4@MnO2–rGO-based peroxidase mimetic system displayed an excellent analytical performance with low cost, satisfactory reproducibility and high selectivity, which could be further extended for detecting other disease-related biomarkers.