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Response to temperature stress of reactive oxygen species scavenging enzymes in the cross-tolerance of barley seed germination

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第12期11卷 965-972页

作者： yu-qin MEI song-quan song Institute of Botany Chinese Academy of Sciences Beijing 100093 China

A number of studies have shown the existence of cross-tolerance in plants, but the physiological mechanism is poorly understood. In this study, we used the germination of barley seeds as a system to investigate the cross-tolerance of low-temperature pretreatment to high-temperature stress and the possible involvement of reactive oxygen species （ROS） scavenging enzymes in the cross-tolerance. After pretreatment at 0 ℃ for different periods of time, barley seeds were germinated at 35 ℃, and the content of malondialdehyde （MDA） and the activities of ROS scavenging enzymes were measured by a spectrophotometer analysis. The results showed that barley seed germinated very poorly at 35 ℃, and this inhibitive effect could be overcome by pretreatment at 0 ℃. The MDA content varied, depending on the temperature at which seeds germinated, while barley seeds pretreated at 0 ℃ did not change the MDA content. Compared with seeds germinated directly at 35 ℃, the seeds pretreated first at 0 ℃ and then germinated at 35 ℃ had markedly increased activities of superoxide dismutase （SOD）, ascorbate peroxidase （APX）, catalase （CAT）, and glutathione reductase （GR）. The SOD and APX activities of seeds germinated at 35 ℃ after 0 ℃-pretreatment were even substantially higher than those at 25 ℃, and GR activity was similar to that at 25 ℃, at which the highest germination performance of barley seeds was achieved. These results indicate that low-temperature pretreatment can markedly increase the tolerance of barley seed to high temperature during germination, this being related to the increase in ROS scavenging enzyme activity. This may provide a new method for increasing seed germination under stress environments, and may be an excellent model system for the study of cross-tolerance.

关键词： Barley seed Cross-tolerance Germination/growth Reactive oxygen species (ROS) scavenging enzyme,Pretreatment at low temperature Temperature stress

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Synthesis of 2-Phenyl-10-substituted Hymenialdisine Derivatives

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Chemical Research in Chinese Universities 2011年第6期27卷 977-980页

作者： WU Yi WANG yu qin Yong song Hao Department of Chemistry of Medicinal Natural Products West China School of Pharmacy Sichuan University Chengdu 610041 P. R. China

A series of novel 2-phenyl-10-substituted hymenialdisine derivatives was synthesized via the micro-wave-assisted Suzuki-Miyaura cross-coupling reactions of the 2-phenyl derivative of hymenialdisine and boronic acid, which enabled the successful introduction of electron-donating and electron-withdrawing groups to the 2-phenyl- hymenialdisine derivatives in good yields.

关键词： Hymenialdisine Suzuki-Miyaura reaction 2-Phenyl-10-substituted hymenialdisine derivative

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Secondary lymphoma develops in the setting of heart failure when treating breast cancer: A case report

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World Journal of Clinical Cases 2019年第12期7卷 1492-1498页

作者： Sen Han Tao An Wei-Ping Liu yu-qin song Jun Zhu Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Department of Lymphoma Peking University Cancer Hospital and Institute Beijing 100142 China Fuwai Hospital National Center for Cardiovascular Diseases Chinese Academy of Medical Science and Peking Union Medical College Heart Failure Center Beijing 100142 China

BACKGROUND Cardiovascular side effects occur frequently during anti-cancer treatment, and there is a growing concern that they may lead to premature morbidity and death. CASE SUMMARY A 32-year-old woman was diagnosed with breast cancer. After comprehensive treatment with neoadjuvant chemotherapy, surgery, postoperative adjuvant chemotherapy, postoperative adjuvant radiotherapy, and endocrine therapy, her breast cancer was cured. However, heart failure associated with anti-cancer treatment presented, most probably related to chemotherapy containing anthracycline. After active treatment, her cardiac function returned to normal. Unfortunately, follow-up visits revealed a second primary malignancy, lymphoma. After multiple courses of chemotherapy combined with targeted therapy, her lymphoma acquired complete remission and no cardiotoxicity was observed again. Heart failure related to breast treatment may be reversible. CONCLUSION Using alternatives to anthracycline in patients with lymphoma who are at risk of cardiac failure may preserve cardiac function.

关键词： Breast cancer Chemotherapy Cardiac toxicity Heart failure Anthracycline Cardio-oncology Case report

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Water-assisted and protein-initiated fast and controlled ring-opening polymerization of proline N-carboxyanhydride

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National Science Review 2022年第8期9卷 89-99页

作者： Yali Hu Zi-You Tian Wei Xiong Dedao Wang Ruichi Zhao Yan Xie yu-qin song Jun Zhu Hua Lu Beijing National Laboratory for Molecular Sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of the Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking University Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary StudiesPeking University Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Department of LymphomaPeking University Cancer Hospital and Institute

The production of polypeptides via the ring-opening polymerization(ROP) of N-carboxyanhydride(NCA) is usually conducted under stringent anhydrous conditions. The ROP of proline NCA(ProNCA)for the synthesis of poly-L-proline(PLP) is particularly challenging due to the premature product precipitation as polyproline type I helices, leading to slow reactions for up to one week, poor control of the molar mass and laborious workup. Here, we report the unexpected water-assisted controlled ROP of Pro NCA, which affords well-defined PLP as polyproline II helices in 2–5 minutes and almost-quantitative yields. Experimental and theoretical studies together suggest the as-yet-unreported role of water in facilitating proton shift, which significantly lowers the energy barrier of the chain propagation. The scope of initiators can be expanded from hydrophobic amines to encompass hydrophilic amines and thiol-bearing nucleophiles, including complex biomacromolecules such as proteins. Protein-mediated ROP of ProNCA conveniently affords various protein-PLP conjugates via a grafting-from approach. PLP modification not only preserves the biological activities of the native proteins, but also enhances their resistance to extreme conditions. Moreover, PLP modification extends the elimination half-life of asparaginase(ASNase) 18-fold and mitigates the immunogenicity of wt ASNase >250-fold(ASNase is a first-line anticancer drug for lymphoma treatment). This work provides a simple solution to a long-standing problem in PLP synthesis,and offers valuable guidance for the development of water-resistant ROP of other proline-like NCAs. The facile access to PLP can greatly boost the application potential of PLP-based functional materials for engineering industry enzymes and therapeutic proteins.

关键词： proline PPII helix ring-opening polymerization N-carboxyanhydride protein-polymer conjugates

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Relapsed/refractory classical Hodgkin lymphoma effectively treated with low-dose decitabine plus tislelizumab:A case report

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World Journal of Clinical Cases 2021年第21期9卷 6041-6048页

作者： Xiao-Sheng Ding Lan Mi yu-qin song Wei-Ping Liu Hui yu Ning-Jing Lin Jun Zhu Department of Lymphoma Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education)Peking University Cancer Hospital&InstituteBeijing 100142China

BACKGROUND Academic studies have proved that anti-programmed death-1(PD-1)monoclonal antibodies demonstrated remarkable activity in relapsed/refractory classical Hodgkin lymphoma(cHL).However,most patients ultimately experienced failure or *** is urgent and necessary to develop a novel strategy for relapsed/refractory *** aim of this case report is to evaluate the combination approach of low-dose decitabine plus a PD-1 inhibitor in relapsed/refractory cHL patients with prior PD-1 inhibitor *** SUMMARY The patient was a 27-year-old man who complained of enlarged right-sided cervical lymph nodes and progressive pain aggravation of the right shoulder over the past 3 mo before *** analysis of lymph node biopsy was suggestive of *** patient experienced failure of eight lines of therapy,including multiple cycles of chemotherapy,PD-1 blockade,and anti-CD47 antibody ***-enhanced CT showed that the tumors of the chest and abdomen significantly shrunk or disappeared after three cycles of treatment with decitabine plus *** patient had been followed for 11.5 mo until March 2,2021,and no progressive enlargement of the tumor was *** The strategy of combining low-dose decitabine with tislelizumab could reverse the resistance to PD-1 inhibitors in patients with heavily pretreated relapsed/refractory *** therapeutic effect of this strategy needs to be further assessed.

关键词： Immunotherapy Hypomethylating agent Classical Hodgkin lymphoma Survival Case report

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Hepatitis B surface antigen seroconversion after HBV reactivation in non-Hodgkin's lymphoma

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World Journal of Gastroenterology 2014年第17期20卷 5165-5170页

作者： Wei-Ping Liu Wen Zheng yu-qin song Ling-Yan Ping Gui-Qiang Wang Jun Zhu Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Department of LymphomaPeking University Cancer Hospital and Institute Department of Infectious Diseases Center for Liver DiseasesPeking University First Hospital

Reactivation of hepatitis B virus(HBV)can occur in lymphoma patients infected with HBV when they receive chemotherapy or *** administration of lamivudine(LAM)reduces the morbidity and mortality associated with HBV ***,what defines HBV reactivation and the optimal duration of treatment with LAM have not yet been clearly *** reactivation may occur due to the cessation of prophylactic LAM,although re-treatment with nucleoside analogs may sometimes result in hepatitis B surface antigen(HBsAg)seroconversion,which is a satisfactory endpoint for the management of HBV *** report a case of HBV reactivation in a 68-year-old HBsAg-positive patient who received rituximab-based immunochemotherapy for follicular *** reactivation developed following cessation of prophylactic LAM *** patient subsequently received treatment with entecavir(ETV),which led to a rapid and sustained suppression of HBV replication and HBsAg *** also appraised the literature concerning HBV reactivation and the role of ETV in the management of HBV reactivation in lymphoma patients.A total of 28 cases of HBV reactivation have been reported as having been treated with ETV during or after immunosuppressive chemotherapy in lymphoma *** conclude that ETV is an efficacious and safe treatment for HBV reactivation following LAM cessation in lymphoma patients treated with rituximab-based immunochemotherapy.

关键词： Hepatitis B surface antigen, Seroconversion, Non-Hodgkin’ s lymphoma, Rituximab, Entecavir

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Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang Xie Zhi-Liang qin Jian-Hua Wang Peng song Heng-Guang Shen Sheng-Qi yu Ben-Jun Ma Xue-qin Liu qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute Co. Ltd.Beijing100028China College of Marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment Co. Ltd.Weihai264209ShandongChina

The low-wavenumber components in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber components in the gradient will also reduce the convergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient combines the conventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber components in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber components in the high-frequency inversion to improve the convergence *** results of synthetic data experiment demonstrate that compared to the conventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber components in the gradient under the premise of ensuring inversion *** also greatly enhances the convergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber component

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Association between Gene Polymorphisms and SNP-SNP Interactions of the Matrix Metalloproteinase 2 Signaling Pathway and the Risk of Vascular Senescence

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Biomedical and Environmental Sciences 2024年第2期37卷 146-156页

作者： LIAO Zhen yu YANG Shuo HU song LIU Jia MAO Yong Jun SUN Shu qin Department of Geriatrics the Affiliated Hospital of Qingdao UniversityQingdao 266000ShandongChina Department of Critical Care Medicine the Affiliated Hospital of Qingdao UniversityQingdao 266000ShandongChina

Objective This study aimed to explore the association of single nucleotide polymorphisms(SNP)in the matrix metalloproteinase 2(MMP-2)signaling pathway and the risk of vascular senescence(VS).Methods In this cross-sectional study,between May and November 2022,peripheral venous blood of151 VS patients(case group)and 233 volunteers(control group)were *** SNPs were identified in five genes encoding the components of the MMP-2 signaling pathway,assessed through carotid-femoral pulse wave velocity(cf PWV),and analyzed using multivariate logistic *** multigene influence on the risk of VS was assessed using multifactor dimensionality reduction(MDR)and generalized multifactor dimensionality regression(GMDR)*** Within the multivariate logistic regression models,four SNPs were screened to have significant associations with VS:chemokine(C-C motif)ligand 2(CCL2)rs4586,MMP2 rs14070,MMP2rs7201,and MMP2 *** of the T/C genotype of MMP2 rs14070 had a 2.17-fold increased risk of developing VS compared with those of the C/C genotype,and those of the T/T genotype had a19.375-fold increased ***2 rs4586 and MMP-2 rs14070 exhibited the most significant *** CCL2 rs4586,MMP-2 rs14070,MMP-2 rs7201,and MMP-2 rs1053605 polymorphisms were significantly associated with the risk of VS.

关键词： Vascular senescence Pulse wave velocity(PWV) Single nucleotide polymorphism(SNP) Matrix metalloproteinase 2(MMP-2) Extracellular matrix(ECM) Structural degradation Multifactor dimensionality reduction(MDR)

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High-Performanceα-Diimine Nickel Complexes for Facile Access of PE Elastomers with Exceptional Material Properties

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Chinese Journal of Polymer Science 2024年第5期42卷 620-635,I0008页

作者： Li-Dong qin Xin-yu Wang Qaiser Mahmood Zhi-Xin yu Yi-Zhou Wang song Zou Tong-Ling Liang Wen-Hua Sun School of Pharmaceutical Sciences Changchun University of Chinese MedicineChangchun130117China Chemistry and Chemical Engineering Guangdong Laboratory Shantou515031China Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China

For practicable elastomeric polyethylene,achieving high catalyst thermal stability and activity,along with precise control of polymer properties such as branching density,molecular weights,and distribution,is crucial but *** this study,two sets of symmetricalα-diimine nickel complexes,each comprising four nickel bromide or chloride complexes,were synthesized and investigated their performance for ethylene polymerization under various reaction *** activation with either Et2AlCl or MMAO cocatalysts,these complexes displayed not only high activity but also generated high molecular weight polyethylenes with controlled polydispersity and a substantial number of *** catalyst with the least steric hindrance displayed the remarkable high activity(up to 1.2×10^(7) g·mol^(-1)·h^(-1)).Notably,nickel bromides demonstrated higher activity compared to their chloride *** investigation into the effect of reaction temperature on catalytic performance revealed that NiBrMe-MMAO system displayed high thermal stability(activity up to 2.51×10^(6) g·mol^(-1)·h^(-1) at 100℃)and consistently yielded high polymer molecular weights with narrow polydispersity over a broad temperature range of 30-100℃.Of significant note,mechanical analysis of the resulting polyethylene demonstrated excellent ultimate tensile strength and high strain at ***,the polyethylene sample prepared at 100℃exhibited ultimate tensile strength up to 10 MPa with 1863%maximum strain at break and a strain recovery of up to 54.9%after ten cycles at a fixed strain of 300%,indicating excellent material properties of prepared thermoplastic polyethylene elastomers(TPE).

关键词： Thermoplastic polyethylene elastomers α-Diimine nickel pre-catalysts Ethylene polymerization Mechanical properties Highly branched polyethylene

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Resource Allocation in Multi-User Cellular Networks:A Transformer-Based Deep Reinforcement Learning Approach

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China Communications 2024年第5期21卷 77-96页

作者： Zhao Di Zheng Zhong qin Pengfei qin Hao song Bin State Key Laboratory of Integrated Services Networks Xidian University710071China China Academy of Space Technology Beijing 100081China

To meet the communication services with diverse requirements,dynamic resource allocation has shown increasing *** this paper,we consider the multi-slot and multi-user resource allocation(MSMU-RA)in a downlink cellular scenario with the aim of maximizing system spectral efficiency while guaranteeing user *** first model the MSMURA problem as a dual-sequence decision-making process,and then solve it by a novel Transformerbased deep reinforcement learning(TDRL)***,the proposed TDRL approach can be achieved based on two aspects:1)To adapt to the dynamic wireless environment,the proximal policy optimization(PPO)algorithm is used to optimize the multi-slot RA strategy.2)To avoid co-channel interference,the Transformer-based PPO algorithm is presented to obtain the optimal multi-user RA scheme by exploring the mapping between user sequence and resource *** results show that:i)the proposed approach outperforms both the traditional and DRL methods in spectral efficiency and user fairness,ii)the proposed algorithm is superior to DRL approaches in terms of convergence speed and generalization performance.

关键词： dynamic resource allocation multi-user cellular network spectrum efficiency user fairness

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