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A novel insight of enhancing the hydrogen peroxide tolerance of unspecific peroxygenase from Daldinia caldariorum based on structure

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Chinese Chemical Letters 2024年第4期35卷 426-430页

作者： tiantian Li Ruochen jin Bin Wu Dongming Lan Yunjian Ma Yonghua Wang School of Food Science and Engineering South China University of TechnologyGuangzhou 510640China School of Bioscience and Bioengineering South China University of TechnologyGuangzhou 510006China Guangdong Youmei Institute of Intelligent Bio-manufacturing Co. Ltd.Foshan 528200China

Unspecific peroxygenases(UPOs, EC 1.***.2.1) is a kind of thioheme enzyme capable of catalyzing various oxidations of inert C–H bonds using H_(2)O_(2) as an oxygen donor without cofactors. However, the enhancement of the H_(2)O_(2) tolerance of UPOs is always challenging. In this study, the A161C mutant of r Dca UPO,which originates from Daldinia caldariorum, was found to be highly H_(2)O_(2)-resistant. Compared with the wild type, the mutant r Dca UPO-A161C showed a 10-h prolonged half-life and a 64% improved enzyme activity when incubated in 10 mmol/L H_(2)O_(2). The crystal structure analysis at 1.47 A showed that r Dca UPOA161C exhibited 10 α-helixes(cyan) and a series of ordered rings, forming a single asymmetric spherical structure. The two conserved domains near heme formed an active site with the catalytic PCP and EHD regions(Glu86, His87, Asp88 residues). The H_(2)O_(2) tolerance of r Dca UPO-A161C was preliminarily explored by comparing its structure with the wild type. Notably, r Dca UPO-A161C showed significantly higher catalytic efficiency than the wild type for the production of hydroxyl fatty acids. This study is anticipated to provide an insight into the structure-function relationship and expand potential applications of UPOs.

关键词： Unspecific peroxygenase Molecular modification Hydrogen peroxide stability Crystal structure Hydroxyl fatty acids

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电力负荷与气象因子因果关系分析及预测研究

机电工程技术 2024年第3期53卷 253-257,318页

作者：张一博杨宗记张建东李瑞盈张晨宇靳甜甜秦皇岛市气象局河北秦皇岛066000

短期电力负荷预测是电力部门生产调度的重要参考,不同地区影响电力负荷的因素有所不同,因此,为探索电力负荷与气象因子之间的因果关系,以某变电站逐小时电力负荷和气象要素数据为基础,采用格兰杰因果检验分析气象要素与电力负荷的因果... 详细信息

短期电力负荷预测是电力部门生产调度的重要参考,不同地区影响电力负荷的因素有所不同,因此,为探索电力负荷与气象因子之间的因果关系,以某变电站逐小时电力负荷和气象要素数据为基础,采用格兰杰因果检验分析气象要素与电力负荷的因果关系。采用ADF检验验证气象因子与电力负荷数据的平稳性,将通过ADF检验的平稳性变量进行格兰杰因果检验。结果显示,温度、相对湿度和风速均是电力负荷的格兰杰原因,温度和相对湿度对电力负荷变化的影响是实时的,风速对电力负荷变化的影响具有1 h以上的滞后性。采用灰色关联度和余弦相似度建立综合相似性指标,基于相似日法提出一种短期电力负荷预测模型,以2018—2020年的气象数据和电力负荷数据作为样本库,采用2021年的数据对模型预测准确性进行检验。经验证,模型在天气因子变化不明显或变化缓慢情况下预测准确率为90%以上,可作为电力部门生产调度参考。

关键词：短期电力负荷预测格兰杰因果检验相似日法

Assessing Adaptability of Planted Trees Using Leaf Traits: A Case Study with Robinia pseudoacacia L. in the Loess Plateau, China

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Chinese Geographical Science 2011年第3期21卷 290-303页

作者： jin tiantian LIU Guohua FU Bojie DING Xiaohui YANG Lei State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Leaf trait patterns and their variations with climate are interpreted as an adaptive adjustment to *** study assessed the adaptability of planted black locust (Robinia pseudoacacia L.) based on the analysis of leaf traits and the comparison of its leaf traits with inter-specific ones existing in the same *** measured some water and N use related leaf traits: leaf dry mass per unit area (LMA) and N,P and K concentrations based on both leaf area (Narea,Parea and Karea) and leaf mass (Nmass,Pmass and Kmass) of *** at 31 sites along a water stress gradient in North Shaanxi Province,*** results show that leaves of *** have high Nmass and low LMA in the study *** Nmass and low LMA are usually representative of luxurious resource use,and will advance plant resource competitiveness in high-resource *** a whole,LMA-nutrient relationships of *** display patterns that are fairly similar to the inter-specific relationships in both direction and *** tendency for LMA and Narea to increase with decreasing water availability and the positive correlation between LMA and Narea reflect the trend for *** to enhance water use efficiency (WUE) at the expense of down-regulated photosynthetic N use efficiency (PNUE) and high construction cost in dry ***,the positive relationship between LMA and Narea in high mean annual precipitation (MAP) area is either unremarkable or reversed with decreasing water *** implies a lower photosynthetic capacity and a higher construction cost for high-LMA *** inter-specific relationship between LMA and Narea is positive and does not change with water *** difference between inter-species and intra-species may be due to more diversified anatomies and more specialised structures for inter-species than *** failure of *** adaption to dry conditions reflected by LMA-Narea relationship may be partial

关键词： water stress planted tree leaf trait Robinia pseudoacacia L. tradeoff Loess Plateau

Genetic landscape and clinical significance of cuproptosis-related genes in liver hepatocellular carcinoma

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Genes & Diseases 2024年第2期11卷 516-519页

作者： Dingtao Hu Yichuan Wang Xu Shen tiantian Mao Xijun Liang Tengjiao Wang Weifeng Shen Yugang Zhuang jin Ding Clinical Cancer Institute Center for Translational MedicineNaval Medical UniversityShanghai 200433China Department of Emergency Shanghai Tenth People's HospitalTongji UniversitySchool of MedicineShanghai 200072China Bioinformatics Analysis Laboratory Center for Translational MedicineNaval Medical UniversityShanghai 200433China The Department of Hepatic Surgery Eastern Hepatobiliary Surgery HospitalNaval Medical UniversityShanghai 200433China

Recently,Peter et al reported a novel form of cell death(cuproptosis)that was different from other known death mechanisms.1 They found that accumulation of copper ions could induce destabilization of Fe-S cluster proteins and aggregation of mitochondrial lipoylated proteins,ultimately resulting in cuproptosis.1 of note,ten genes were identified as cuproptosis-related genes(CRGs)in copper ion-induced cell death,including PDHB,PDHA1,DLAT,DLD,LIPT1,LIAS,FDX1,CDKN2A,GLS,and MTF1.1 Since dysregulation of copper metabolism is involved in many cancers,cuproptosis and CRGs may play vital roles in cancer development and treatment.1.2 Herein,our pancancer analysis revealed the coordinated upregulation of 9 of 10 CRGs in human liver hepatocellular carcinoma(LIHC)across 33 solid tumors(Fig.S1A;Fig.1A),suggesting the distinct role of CRGs in *** then explored the genetic landscape,biological function,and clinical significance of CRGs in LIHC,and validated our bioinformatic findings by in vitro experiments and clinical *** detailed methods were described in the supplementary material.

关键词： clinical metabolism hepatocellular

Do Forest Landscape Pattern Planning and Optimization Play a Role in Enhancing Soil Conservation Services in Mountain Areas of Western China?

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Chinese Geographical Science 2021年第5期31卷 848-866页

作者： GONG Jie ZHANG jinxi ZHANG Yunxia ZHU Yuehua jin tiantian XU Caixian College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China

The relationship between landscape patterns and soil conservation,as well as the need for nature-based soil erosion control and landscape pattern optimization,have increasingly gained attention in the scientific and political community in the past *** the implementation of a series of afforestation/reforestation projects in the western China,the optimization and management of forest landscape patterns will become more important for soil *** this study,the Bailongjiang Watershed(BLJW),in the western China,was used as a case study to explore the relationship between the forest landscape pattern and soil conservation services using mathematical and spatial statistics methods.A spatially-explicit model called the sediment delivery ratio(SDR)model of the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)was used to assess the soil conservation service in each sub-basin of BLJW in 1990,2002,and 2014,and landscape indices were used to describe changes in forest landscape patterns in each *** forest landscape indices,including the percentage of landscape(PLAND),largest patch index(LPI),edge density(ED),landscape shape index(LSI),mean patch shape(SHAPEMN),patch cohesion index(COHESION),landscape division index(DIVISION),splitting index(SPLIT)and aggregation index(AI),were significantly correlated to the soil conservation ***,AI,LSI and SPLIT of forestland were determined to be the more important landscape *** results also indicated that soil conservation was substantially *** results demonstrated that landscape type diversity greatly affected watershed soil conservation and can be used for forest landscape restoration and ***,spatial statistics analysis indicated that the Spatial Lag Model(SLM)was superior to the Ordinary Least Squares(OLS)for soil conservation regressions in 1990 and 2014,while OLS was more appropriate for the regression in *** findings will be useful

关键词： forest landscape landscape pattern soil conservation service afforestation integrated landscape management

Glutathione-depleted cyclodextrin pseudo-polyrotaxane nanoparticles for anti-inflammatory oxaliplatin(Ⅳ) prodrug delivery and enhanced colorectal cancer therapy

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Chinese Chemical Letters 2024年第4期35卷 280-286页

作者： Wenjia Wang Xingyue He Xiaojie Wang tiantian Zhao Osamu Muraoka Genzoh Tanabe Weijia Xie Tianjiao Zhou Lei Xing Qingri jin Hulin Jiang State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China Faculty of Pharmacy Kinki University HigashiosakaOsaka 577-8502Japan State Key Laboratory of Natural Medicines(SKLNM)and Department of Medicinal Chemistry School of PharmacyChina Pharmaceutical UniversityNanjing 210009China School of Pharmacy Hangzhou Medical CollegeHangzhou 311399China College of Pharmacy Yanbian UniversityYanji 133002China

Oxaliplatin(Oxa) is the first-line chemotherapeutic drug for the treatment of colorectal cancer(CRC). However, long-term Oxa chemotherapy can induce inflammation and increase the levels of cyclooxygenase-2(COX-2) and prostaglandin E2(PGE2), which can promote tumor metastasis. Moreover,high glutathione(GSH) levels in CRC cells significantly reduce Oxa sensitivity and seriously restrict the clinical application of Oxa. Herein, an Oxa(Ⅳ) prodrug with anti-inflammatory properties(desmethyl naproxe, DN) and GSH-depleting cyclodextrin pseudo-polyrotaxane carriers were prepared and further self-assembled into micellar nanoparticles(designated DNPt@PPRI). The relesae of DN from DNPt@PPRI can reduce the level of PGE2 to inhibit inflammation and tumor metastasis by decreasing COX-2 protein,and also synergize with Oxa to inhibit tumor. More importantly, GSH depletion can reduce the detoxification of Oxa and further enhance chemotherapy-induced apoptosis. DNPt@PPRI have a good GSH depletion ability to enhance the sensitivity of Oxa, indicating a potential in the synergistic chemotherapy and chemo-sensitization of colorectal cancer.

关键词： Oxaliplatin Glutathione depletion Tetravalent platinum prodrug Synergistic therapy Colorectal cancer

A cell transcriptomic profile p ovides insights into adipocytes of porcine mammary gland across development

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Journal of Animal Science and Biotechnology 2024年第1期15卷 182-200页

作者： Yongliang Fan Long jin Zhiping He tiantian Wei Tingting Luo Jiaman Zhang Can Liu Changjiu Dai Chao A Yan Liang Xuan Tao Xuebin Lv Yiren Gu Mingzhou Li State Key Laboratory of Swine and Poultry Breeding Industry College of Animal Science and TechnologySichuan Agricultural UniversityChengdu 611130China Key Laboratory of Qinghai‑Tibetan Plateau Animal Genetic Resource Reservation and Utilization Southwest Minzu UniversityChengdu 610041China Animal Breeding and Genetics Key Laboratory of Sichuan Province Sichuan Animal Science AcademyChengdu 610000China

Background Studying the composition and developmental mechanisms in mammary gland is crucial for healthy growth of newborns. The mammary gland is inherently heterogeneous, and its physiological function dependents on the gene expression of multiple cell types. Most studies focused on epithelial cells, disregarding the role of neighboring *** Here, we constructed the largest transcriptomic dataset of porcine mammary gland cells thus far. The dataset captured 126,829 high-quality nuclei from physiological mammary glands across five developmental stages(d 90 of gestation, G90;d 0 after lactation, L0;d 20 after lactation, L20;2 d post natural involution, PI2;7 d post natural involution, PI7). Seven cell types were identified, including epithelial cells, adipocytes, endothelial cells, fibroblasts cells, immune cells, myoepithelial cells and precursor cells. Our data indicate that mammary glands at different developmental stages have distinct phenotypic and transcriptional signatures. During late gestation(G90), the differentiation and proliferation of adipocytes were inhibited. Meanwhile, partly epithelial cells were completely differentiated. Pseudo-time analysis showed that epithelial cells undergo three stages to achieve lactation, including cellular differentiation, hormone sensing, and metabolic activation. During lactation(L0 and L20), adipocytes area accounts for less than 0.5% of mammary glands. To maintain their own survival, the adipocyte exhibited a poorly differentiated state and a proliferative capacity. Epithelial cells initiate lactation upon hormonal stimulation. After fulfilling lactation mission, their undergo physiological death under high intensity lactation. Interestingly, the physiological dead cells seem to be actively cleared by immune cells via CCL21-ACKR4 pathway. This biological process may be an important mechanism for maintaining homeostasis of the mammary gland. During natural involution(PI2 and PI7), epithelial cell populatio

关键词： Adipocytes Cell–cell interaction Development Mammary gland snRNA-seq

Comparison of transpiration between different aged black locust(Robinia pseudoacacia)trees on the semi-arid Loess Plateau,China

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Journal of Arid Land 2016年第4期8卷 604-617页

作者： JIAOLei LU Nan FU Bojie GAO Guangyao WANG Shuai jin tiantian ZHANG Liwei LIU Jianbo ZHANG Di State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Joint Center(or Global Change Studies Beijing 100875China China Institute of Water Resources andHydropower Research Beijing 100038China College of Tourism and Environment Shaanxi Normal UniversityXi'an 710119China College of Earth and Environmental Science Lanzhou UniversityLanzhou 730000China

Black locust （Robinia pseudoacacia） is widely planted throughout the semi-arid Loess Plateau of China. The spatial distribution of this species at different ages is highly heterogeneous due to restoration and management practices. In this study, we aimed to compare the transpiration levels between different aged black locusts at the tree and stand scales, clarifying the physiological status of this species with different ages. Black locust trees with two representative age classes （12 and 28 years） were selected in the Yangjuangou catchment on the semi-arid Loess Plateau. Sap flux density （Fd） and environmental variables （solar radiation, air temperature, relative humidity and soil water content） were simultaneously monitored throughout the growing season of 2014. Tree transpiration （Et） was the product of Fd and sapwood area （As）, and stand transpiration （Ec） was calculated basing on the stand sap flux density （Js） and stand total sapwood area （AsT）. Stomatal conductance （gs） was measured in a controlled environment and hydraulic conductance was estimated using the relationship between transpiration rate and vapor pressure deficit （VPD）. Our results showed that Et and Ec were higher in the 28-year-old stand than in the 12-year-old stand. The gs and hydraulic conductance of 28-year-old trees were also higher than those of 12-year-old trees, and the two parameters were thus the causes of variations in transpiration between different age classes. After rainfall, mean Fd increased by 9% in 28-year-old trees and by 5% in 12-year-old trees. This study thus suggests that stand age should be considered for estimating transpiration at the catchment and region scales in this area. These results provide ecophysiological evidences that the older black locust trees had more active physiological status than the younger ones in this area. These findings also provide basic information for the management of water resources and forests on the semi-arid Loess Plateau.

关键词： sapflow transpiration stand age afforestation restoration Loess Plateau

Regulating microstructure and composition by carbonizing in-situ grown metal-organic frameworks on cotton fabrics for boosting electromagnetic wave absorption

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Nano Research 2024年第8期17卷 7290-7300页

作者： Jie jin Hongsen Long Hu Liu Yan Guo tiantian Bai Ben Bin Xu Mohammed A.Amin Hua Qiu Mohamed H.Helal Chuntai Liu Changyu Shen Zeinhom M.El-Bahy Zhanhu Guo State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou UniversityZhengzhou 450002China China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410000China School of Electronic Engineering North China University of Water Resources and Electric PowerZhengzhou 450046China Complex Conditions of High-end Tire Technology Innovation Center Shuguang Rubber Industry Research&Design Institute Co.LtdGuilin 541004China Integrated Composites Lab Department of Mechanical and Civil EngineeringNorthumbria UniversityNewcastle Upon TyneNE18STUK Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Chemistry Faculty of Arts and ScienceNorthern Border UniversityRafha 73213Saudi Arabia Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City 11884CairoEgypt

High-temperature carbonized metal-organic frameworks(MOFs)derivatives have demonstrated their superiority for promising electromagnetic wave(EMW)absorbers,but they still suffer from limited EMW absorption capacity and narrow *** the advantage of microstructure and chemical composition regulation for the design of EMW absorber,hierarchical heterostructured MoS_(2)/CoS_(2)-Co_(3)O_(4)@cabonized cotton fabric(CF)(MCC@CCF)is prepared by growing ZIF-67 MOFs onto CF surface,chemical etching,and *** from the dual loss mechanism of magnetic-dielectric multicomponent carbonized MOFs,chemical etching and carbonization process can effectively introduce abundant micro-gap structure that can result in better impedance matching and stronger absorption capacity via internal reflection,doped heteroatoms(Mo,N,S)to supply additional dipolar polarization loss,and numerous heterointerfaces among MoS_(2),CoS_(2),Co_(3)O_(4),and CCF that produce promoted conduction loss and interfacial polarization ***,a minimal reflection loss of−52.87 dB and a broadest effective absorption bandwidth of 6.88 GHz were achieved via tunning the sample thickness and filler loading,showing excellent EMW absorption *** research is of great value for guiding the research on MOFs derivatives based EMW absorbing materials.

关键词： metal-organic frameworks hierarchical structure chemical etching sulfurization electromagnetic wave absorption