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Chinese Journal of Natural Medicines 2022年第9期20卷 691-700页

作者： CHEN Xiao-Chao LU yun LIU Yuan ZHOU Jia-Wei ZHANG Yi-Feng gao hai-yun LIDan gao Wei School of Traditional Chinese Medicine Capital Medical UniversityBeijing 100069China Beijing Shijitan Hospital Capital Medical UniversityBeijing 100038China

Tripterygium hypoglaucum(Levl.)Hutch,a traditional Chinese medicinal herb with a long history of use,is widely distributed in China.One of its main active components,celastrol,has great potential to be developed into anti-cancer and anti-obesity drugs.Although it exhibits strong pharmacological activities,there is a lack of sustainable sources of celastrol and its derivatives,making it crucial to develop novel sources of these drugs through synthetic biology.The key step in the biosynthesis of celastrol is considered to be the cyclization of 2,3-oxidosqualene into friedelin under the catalysis of 2,3-oxidosqualene cyclases.Friedelin was speculated to be oxidized into celastrol by cytochrome P450 oxidases(CYP450s).Here,we reported a cytochrome P450 ThCYP712K1 from Tripterygium hypoglaucum(Levl.)Hutch that catalyzed the oxidation of friedelin into polpuonic acid when heterologously expressed in yeast.Through substrate supplementation and in vitro enzyme analysis,ThCYP712K1 was further proven to catalyze the oxidation of friedelin at the C-29 position to produce polpunonic acid,which is considered a vital step in the biosynthesis of celastrol,and will lay a foundation for further analysis of its biosynthetic pathway.

关键词： Tripterygium hypoglaucum Cytochrome P450 Polpunonic acid Celastrol Biosynthesis

Caseinolytic mitochondrial matrix peptidase X is essential for homologous chromosome synapsis and recombination during meiosis of male mouse germ cells

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Asian Journal of Andrology 2024年第2期26卷 165-174页

作者： hai-Wei Feng Yu Zhao Yan-Ling gao Dong-Teng Liu Li-Jun Huo Key Laboratory of Agricultural Animal Genetics Breeding and ReproductionEducation Ministry of ChinaCollege of Animal Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China Shenzhen Key Laboratory of Fertility Regulation Reproductive Medicine CenterThe University of Hong Kong-Shenzhen HospitalShenzhen 518053China Maternal-Fetal Medicine Institute Department of Obstetrics and GynaecologyShenzhen Baoan Women's and Children's HospitalJinan UniversityShenzhen 518100China Department of Obstetrics and Gynaecology Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong SARChina

Meiosis is the process of producing haploid gametes through a series of complex chromosomal events and the coordinated action of various proteins.The mitochondrial protease complex(ClpXP),which consists of caseinolytic mitochondrial matrix peptidase X(ClpX)and caseinolytic protease P(ClpP)and mediates the degradation of misfolded,damaged,and oxidized proteins,is essential for maintaining mitochondrial homeostasis.ClpXP has been implicated in meiosis regulation,but its precise role is currently unknown.In this study,we engineered an inducible male germ cell-specific knockout caseinolytic mitochondrial matrix peptidase X(Clpx^(cKO))mouse model to investigate the function of ClpX in meiosis.We found that disrupting Clpx in male mice induced germ cell apoptosis and led to an absence of sperm in the epididymis.Specifically,it caused asynapsis of homologous chromosomes and impaired meiotic recombination,resulting in meiotic arrest in the zygotene-to-pachytene transition phase.The loss of ClpX compromised the double-strand break(DSB)repair machinery by markedly reducing the recruitment of DNA repair protein RAD51 homolog 1(RAD51)to DSB sites.This dysfunction may be due to an insufficient supply of energy from the aberrant mitochondria in Clpx^(cKO) spermatocytes,as discerned by electron microscopy.Furthermore,ubiquitination signals on chromosomes and the expression of oxidative phosphorylation subunits were both significantly attenuated in Clpx^(cKO) spermatocytes.Taken together,we propose that ClpX is essential for maintaining mitochondrial protein homeostasis and ensuring homologous chromosome pairing,synapsis,and recombination in spermatocytes during meiotic prophase I.

关键词： ClpX homologous chromosome meiosis mitochondrial recombination synapsis

A Non-Iterative Network Utilization Pricing Mechanism for P2P Energy Trading

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1301-1306页

作者： yun Liu yunqiang gao Yuanzheng Li Jizhong Zhu Hoay Beng Gooi School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China School of Artificial Intelligence and Automation Ministry of Education Key Laboratory of Image Processing and Intelligence ControlHuazhong University of Science and TechnologyWuhan 430074China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore IEEE

To sustain operation and maintenance of an active distribution network(ADN),a network fee should be charged by the distribution network service provider(DNSP)for facilitating the P2P energy trading service.To this end,this paper models the interaction among the DNSP and multiple prosumers as a Stackelberg game,and then develops a non-iterative and decentralized transactive mechanism to simultaneously achieve optimal network utilization pricing and peer-to-peer(P2P)trading.Simulation results in an ADN with four prosumers connected to a common substation bus validate the effectiveness and efficiency of the proposed scheme.

关键词： Distribution network service provider network fee non-iterative peer-to-peer trading prosumer

Calcium-based polymers for suppression of soil acidification by improving acid-buffering capacity and inhibiting nitrification

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Journal of Environmental Sciences 2024年第5期139卷 138-149页

作者： Fei Kang yunshan Meng Yanning Ge yun Zhang haixiang gao Xueqin Ren Jie Wang Shuwen Hu Beijing Key Laboratory of Farmland Soil Pollution Prevention-control and Remediation College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Department of Applied Chemistry China Agricultural UniversityBeijing 100193China

Soil acidification is a major threat to agricultural sustainability in tropical and subtropical regions.Biodegradable and environmentally friendly materials,such as calcium lignosulfonate(CaLS),calcium poly(aspartic acid)(PASP-Ca),and calcium polyγ-glutamic acid(γ-PGA-Ca),are known to effectively ameliorate soil acidity.However,their effectiveness in inhibiting soil acidification has not been studied.This study aimed to evaluate the effect of CaLS,PASP-Ca,andγ-PGA-Ca on the resistance of soil toward acidification as directly and indirectly(i.e.,via nitrification)caused by the application of HNO_(3)and urea,respectively.For comparison,Ca(OH)_(2)and lignin were used as the inorganic and organic controls,respectively.Among the materials,γ-PGA-Ca drove the substantial improvements in the pH buffering capacity(pHBC)of the soil and exhibited the greatest potential in inhibiting HNO_(3)-induced soil acidification via protonation of carboxyl,complexing with Al~(3+),and cation exchange processes.Under acidification induced by urea,CaLS was the optimal one in inhibiting acidification and increasing exchangeable acidity during incubation.Furthermore,the sharp reduction in the population sizes of ammonia-oxidizing bacteria(AOB)and ammonia-oxidizing archaea(AOA)confirmed the inhibition of nitrification via CaLS application.Therefore,compared to improving soil pHBC,CaLS may play a more important role in suppressing indirect acidification.Overall,γ-PGA-Ca was superior to PASP-Ca and CaLS in enhancing the soil pHBC and the its resistance to acidification induced by HNO_(3) addition,whereas CaLS was the best at suppressing urea-driven soil acidification by inhibiting nitrification.In conclusion,these results provide a reference for inhibiting soil re-acidification in intensive agricultural systems.

关键词： Calcium-based polymer Soil acidification pH buffering capacity Nitrification inhibition

Tribological and Corrosion Properties of the CoCrAlYTaSiC-xCNTs Coatings Deposited by Laser Cladding

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 726-738页

作者： hai Zhao Yi Ding Wei gao Bo Yu Jinghui Li Mingya Zhang School of Material Science and Engineering Anhui University of TechnologyMaanshan243002China Maanshan Iron&Steel Co. LtdMaanshan243000China Applied Technology Research Institute Jiujiang Vocational UniversityJiujiang332000China School of Metallurgical Engineering Anhui University of TechnologyMaanshan243002China

The MCrAlY coating has been potential candidate for the parts applied in friction and corrosion conditions, and CNTs (carbon nanotubes) are expected to improve the service performance of coatings owing to high lubrication and low chemical reactivity. In this work, a systematic investigation on the tribological and corrosion properties of CoCrAlYTaSiC-xCNTs coatings deposited by laser melting was analyzed. Results showed that the coatings had good-quality without typical metallurgical defects. The CNTs addition homogenized and refined the microstructure of coating, and also improved the tribological and corrosion properties. As the CNTs content changed from 0 to 4 wt%, the wear rate of coating decreased from 16.23 × 10^(-3) to 7.58 × 10^(-3) mg m^(−1), the jcorr of coating decreased from 4.13 × 10^(-4) to 1.23 × 10^(-4) A cm^(−2), and the Rct values increased from 12.69 to 25.07 Ω cm2.

关键词： MCrAlY coating Laser melting deposition Friction Electrochemical corrosion

Elaborating strengthen mechanism of Pt-Ir solid solution superalloy at finite temperature

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Rare Metals 2024年第3期43卷 1243-1256页

作者： Wei Yu Xiao-Yu Chong yun-Xuan Zhou Meng-Di Gan Ying-Xue Liang Yan Wei Ai-Min Zhang Chang-Yi Hu Xing-Yu gao Li Chen hai-Feng Song Jing Feng Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093China yunnan Precious Metals Laboratory Co.LTD Kunming650106China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing100088China

Pt-Ir alloy is potential superalloys used above 1300℃because of their high strength and creep resistance.However,the ductility of Pt-Ir alloy has rapidly deteriorated with the increase of Ir,resulting in poor machinability.This work quantitatively evaluated the solid solution strengthening(SSS)and grain refinement strengthening(GRS)of Pt-Ir alloy using first-principles calculations combined with experimental characterization.Here,the stretching force constants in the second nearest neighbor region(SFC^(2nd))of pure Ir(193.7 eV·nm^(-2))are 3.40 times that of pure Pt(57.0 eV·nm^(-2)),i.e.,the interatomic interaction is greatly enhanced with the increase of Ir content,which leads to the decrease of ductility,and modulus misfit plays a dominant role in SSS.Then,the physical mechanisms responsible for the hardness(H_(V))of Pt-Ir alloy,using the power-law-scaled function of electron work function coupled SSS and GRS,are attributed to the electron redistribution caused by different Ir content.Furthermore,a thorough assessment of the thermodynamic characteristics of Pt-Ir binary alloy was conducted,culminating in development of a mapping model that effectively relates enmposition,temperature and strength.The results revealed that the compressive strength incrcases with the Ir content,and the highest strength was observed in Pt_(0.25)Ir_(0.75).This study provides valuable insights into the Pt-Ir alloy system.

关键词： Elastic properties Phonon Solid solution strengthen Force constants CALPHAD

An inulin-type fructan CP-A from Codonopsis pilosula attenuates experimental colitis in mice by promoting autophagy-mediated inactivation of NLRP3 inflammasome

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Chinese Journal of Natural Medicines 2024年第3期22卷 249-264页

作者： ZHOU Jiangtao WANG Jun WANG Jiajing LI Deyun HOU Jing LI Jiankuan BAI yun’e gao Jianping School of Pharmaceutical Science Shanxi Medical UniversityJinzhong 030600China

Inulin-type fructan CP-A,a predominant polysaccharide in Codonopsis pilosula,demonstrates regulatory effects on immune activity and anti-inflammation.The efficacy of CP-A in treating ulcerative colitis(UC)is,however,not well-established.This study employed an in vitro lipopolysaccharide(LPS)-induced colonic epithelial cell model(NCM460)and an in vivo dextran sulfate sodium(DSS)-induced colitis mouse model to explore CP-A’s protective effects against experimental colitis and its underlying mechanisms.We monitored the clinical symptoms in mice using various parameters:body weight,disease activity index(DAI),colon length,spleen weight,and histopathological scores.Additionally,molecular markers were assessed through enzyme-linked immunosorbent assay(ELISA),quantitative real-time polymerase chain reaction(qRT-PCR),immunofluorescence(IF),immunohistochemistry(IHC),and Western blotting assays.Results showed that CP-A significantly reduced reactive oxygen species(ROS),tumor necrosis factor-alpha(TNF-α),and interleukins(IL-6,IL-1β,IL-18)in LPS-induced cells while increasing IL-4 and IL-10 levels and enhancing the expression of Claudin-1,ZO-1,and occludin proteins in NCM460 cells.Correspondingly,in vivo findings revealed that CPA administration markedly improved DAI,reduced colon shortening,and decreased the production of myeloperoxidase(MPO),malondialdehyde(MDA),ROS,IL-1β,IL-18,and NOD-like receptor protein 3(NLRP3)inflammasome-associated genes/proteins in UC mice.CP-A treatment also elevated glutathione(GSH)and superoxide dismutase(SOD)levels,stimulated autophagy(LC3B,P62,Beclin-1,and ATG5),and reinforced Claudin-1 and ZO-1 expression,thereby aiding in intestinal epithelial barrier repair in colitis mice.Notably,the inhibition of autophagy via chloroquine(CQ)diminished CP-A’s protective impact against colitis in vivo.These findings elucidate that CP-A’s therapeutic effect on experimental colitis possibly involves mitigating intestinal inflammation through autophagymediated NLRP3 inflammasome inactivation.Consequently,inul

关键词： Inulin-type fructan CP-A Codonopsis pilosula Ulcerative colitis NLRP3 inflammasome Autophagy

Application of exosomal miRNA mediated macrophage polarization in colorectal cancer:Current progress and challenges

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Oncology Research 2024年第1期32卷 61-71页

作者： yun ZHANG SHALING TANG YUBO gao ZHONGTING LU YUAN YANG JING CHEN TAO LI Department of Oncology School of Clinical MedicineNingxia Medical UniversityYinchuanChina General Hospital of Ningxia Medical University YinchuanChina School of Basic Medical Sciences Ningxia Medical UniversityYinchuanChina Department of Surgical Oncology Tumor HospitalThe General Hospital of Ningxia Medical UniversityYinchuanChina

Colorectal cancer(CRC)is a major global health problem with high morbidity and mortality rates.Surgical resection is the main treatment for early-stage CRC,but detecting it early is challenging.Therefore,effective therapeutic targets for advanced patients are still lacking.Exosomes,tiny vesicles in body fluids,play a crucial role in tumor metastasis,immune regulation,and drug resistance.Interestingly,they can even serve as a biomarker for cancer diagnosis and prognosis.Studies have shown that exosomes can carry miRNA,mediate the polarization of M1/M2 macrophages,promote the proliferation and metastasis of cancer cells,and affect the prognosis of CRC.Since the gastrointestinal tract has many macrophages,understanding the mechanism behind exosomal miRNA-mediated macrophage polarization in CRC treatment is crucial.This article summarizes recent advancements in the study of exosomal miRNAs in CRC and their potential as diagnostic and prognostic markers.

关键词： Colorectal cancer Exosomes microRNA Macrophages Treatment

Investigating the Absorption and Desorption Behavior of Methylene Chloride in the Poly(aryl ether ketone) Film with Different Crystallinities

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Chinese Journal of Polymer Science 2024年第2期42卷 239-246,I0009页

作者： Hong-Ru Yang Jin-Dong Zhang Dong-Ting gao Gang Liu Chun-hai Chen Jia-Nan Yao Center for Advanced Low-Dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620China

Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2)Cl_(2)).We employed attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy analyses to investigate the diffusion behavior of CH_(2)Cl_(2) in PAEK films with different crystallinities.According to the Fickian diffusion model,the calculated diffu sion coefficients of CH_(2)Cl_(2) in PAEK films were observed to decrease with increasing crystallinity.The effect of CH_(2)Cl_(2)absorption and desorption on the mechanical properties of PAEK films with different crystallinity was further analyzed using tensile tests.The tensile tests exhibited that CH_(2)Cl_(2) has two concurrent effects:plasticization and solvent-induced crystallization.Differential scanning calorimetry(DSC) and wide-angle X-ray diffraction(WXRD) techniques further confirmed solvent-induced crystallization behavior.The results would be beneficial to understand the solvent resistance of PAEK materials and consequently provide the practical application conditions of PAEK with a theoretical basis.

关键词： Poly(aryl ether ketone) Diffusion behavior Infrared spectra Solvent-induced crystallization Mechanical properties

Protective effects of CY-09 and astaxanthin on NaIO_(3)-induced photoreceptor inflammation via the NLRP3/autophagy pathway

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1217-1231页

作者： Xiao-Li Wang yun-Xia gao Qiong-Zhen Yuan Ming Zhang Department of Ophthalmology West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

AIM:To study the effect of the NLRP3/autophagy pathway on the photoreceptor inflammatory response and the protective mechanism of CY-09 and astaxanthin(AST).METHODS:ICR mice were intraperitoneally injected NaIO_(3),CY-09,AST successively and divided into 5 groups,including the control,NaIO_(3),NaIO_(3)+CY-09,NaIO_(3)+AST,and NaIO_(3)+CY-09+AST groups.Spectral domain optical coherence tomography and flash electroretinogram were examined and the retina tissues were harvested for immunohistochemistry,enzyme linked immunosorbent assay(ELISA),and Western blotting.Retinal pigment epithelium cell line(ARPE-19 cells)and mouse photoreceptor cells line(661W cells)were also treated with NaIO_(3),CY-09,and AST successively.Cell proliferation was assessed by cell counting kit-8(CCK-8)assay.Apoptosis was analyzed by flow cytometry.Changes in autophagosome morphology were observed by transmission electron microscopy.Quantitative polymerase chain reaction(qPCR)was used to detect NLRP3 and caspase-1.NLRP3,caspase-1,cleaved caspase-1,p62,Beclin-1,and LC3 protein levels were measured by Western blotting.IL-1βand IL-18 were measured by ELISA.RESULTS:Compared with the control group,the activity of NaIO_(3)-treated 661W cells decreased within 24 and 48h,apoptosis increased,NLRP3,caspase-1,IL-1βand IL-18 levels increased,and autophagy-related protein levels increased(P<0.05).Compared with NaIO_(3) group,CY-09 and AST inhibited apoptosis(P<0.05),reduced NLRP3,caspase-1,IL-1βand IL-18 expression(P<0.05),and inhibited autophagy.Compared with the other groups,CY-09 combined with AST significantly decreased NLRP3 expression and inhibited the expression of the autophagy-related proteins p62,Beclin-1,and LC3 in vitro and in vivo(P<0.05).CONCLUSION:CY-09 and AST inhibit NaIO_(3)-induced inflammatory damage through the NLRP3/autophagy pathway in vitro and in vivo.CY-09 and AST may protect retina from inflammatory injury.

关键词： CY-09 astaxanthin retinal degeneration photoreceptor cells inflammation NLRP3