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Scintillation Arc from FRB 20220912A

Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 134-142页

作者： Zi-Wei Wu Robert AMain Wei-Wei Zhu Bing Zhang Peng Jiang Jia-Rui Niu Jin-Lin Han Di Li Ke-Jia Lee Dong-Zi Li Yuan-Pei Yang Fa-Yin Wang Rui Luo Pei Wang Chen-Hui Niu Heng xu Bo-Jun Wang Wei-Yang Wang yong-Kun Zhang Yi Feng De-Jiang Zhou yong-hua xu Can-Min Deng Yu-Hao Zhu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Max-Planck-Institut für Radioastronomie Bonn 53121Germany Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Nevada Center for Astrophysics and Department of Physics and Astronomy University of NevadaLas VegasNV 89154USA CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy University of Chinese Academy of SciencesBeijing 100049China NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa Department of Astronomy Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Cahill Center for Astronomy and Astrophysics California Institute of TechnologyPasadena 91125USA South-Western Institute For Astronomy Research Yunnan UniversityKunming 650504China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210023China CSIRO Space and Astronomy Epping 1710Australia Department of Astronomy School of Physics and Materials ScienceGuangzhou UniversityGuangzhou 510006China Research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Guangxi Key Laboratory for Relativistic Astrophysics Department of PhysicsGuangxi UniversityNanning 530004China

We present the interstellar scintillation analysis of fast radio burst(FRB)20220912A during its extremely active episode in 2022using data from the Five-hundred-meter Aperture Spherical Radio Telescope(FAST).We detect a scintillation arc in the FRB’s secondary spectrum,which describes the power in terms of the scattered FRB signals’time delay and Doppler shift.The arc indicates that the scintillation is caused by a highly localized region.Our analysis favors a Milky Way origin of the ionized interstellar medium(IISM)for the localized scattering medium but cannot rule out a host galaxy origin.We present our method for detecting the scintillation arc,which can be applied generally to sources with irregularly spaced bursts or pulses.These methods could help shed light on the complex interstellar environment surrounding the FRBs and in our Galaxy.

关键词： fast radio burst scintillation FRB 20220912A

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mad-overexpression down regulates the malignant growth and p53 mediated apoptosis in human hepatocellular carcinoma BEL-7404 cells

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Cell Research 1999年第1期9卷 51-59页

作者： ZHAO hua yong hua xu (Shanghai Institute of Cell Biology, Chinese Academy of Sciences, 320 yue-yang Road, Shanghai 200031, China) Shanghai Institute of Cell Biology Chinese Academy of Sciences Shanghai China

Mad protein has been shown as an antagonist of cMyc protein in some cell lines. The effect of Mad protein to the malignant phenotype of human hepatoma BEL7404 cell line was investigated experimentally. An eukarryotic vector pCDNA Ⅲ containing full ORF fragmentof mad cDNA was transfected into targeted cells. Under G418 selection, stable Mad-overexpressed cells were cloned.Studies on the effect of Mad over-expression in cell proliferation and cell cycle revealed that cell morphology of the Mad-overexpressed BEL-7404-M1 cells was significantly different from the parent and control vector transfected cells. DNA synthesis, cell proliferation and anchorage-independent growth in soft-agar of the madtransfected cel1s were partially inhibited in comparison to control cells.Flow Cytometry analysis indicated that mad over-expression might block more transfectant cells at G0/G1 phase, resulting in the retardation of cell proliferation. RT-PCR detected a marked inhibition of the expression of cdc25A, an important regulator gene of G0/G1to S phase in cell cycle. It was also found that Mad protein overexpression could greatly suppress p53-mediated apoptosis in BEL-7404-M1 cells in the absence of serume.Thus, Mad proteins may function as a negative regulator antagonizing c-Myc activity in the control of cell growth and apoptosis in human hepatocellular carcinoma BEL7404 cells.madoverexpression and regulation of cell growth and apoptosis

关键词： Mad c-Myc cell growth apoptosis human hepatoma cells

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Delivery efficiency of periadventitial approach in comparison of intravascular delivery: an assessment of pharmacokinetics in porcine arteries

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中国介入影像与治疗学 2005年第5期2卷 319-324页

作者： yong-hua xu Gordon McLennan Department of Radiology Indiana University School of Medicine Indianapolis 46202 USA

Objective To investigate the delivery efficacy of periadventitial delivery of125I-iododeoxyuridine 125I-IUdR) in comparison of intravascular delivery to determine the optimal delivery method for inhibiting post-angioplasty restenosis. Methods In 8 pigs, one side carotid, subclavian and iliac arteries of each pig were injured by balloon angioplasty with a 20% overstretches. Then, 4 mCi of 125I-IUdR was delivered at each targeted vessel with periadventitial method in 4 pigs （periadventitial group） and with intravascular method via a porous balloon catheter in other 4 pigs （intravascular group）. The animals survived for 5 hours and the blood radioactivity was investigated prior to and hourly after procedure until sacrifice. The targeted vessels and renal arteries （for control） were harvested for gamma-counting and histological observation. Meanwhile, the radioactivity in thyroid, liver, bladder, small bowel and each kidney also were measured to determine the biodistribution of125I. The activities of125I presented in arterial and tissue specimens were compared between the two delivery groups. The targeted arteries were histologically observed and the ratio of intima to media （I∶M ratio） was calculated. Results The target arterial walls in the periadventitial group had 3.4 times as much of125I radioactivity as in the intravascular group, respectively （P=0.038）; the blood activity in intravascular group was significantly higher than periadventitial group immediate after procedure （P0.05）. The mean I: M ratios in both groups were 0.05 without additional injury at the vessel wall. Conclusion The periadventitial delivery offered substantial advantage over intravascular approach with high local delivery efficacy. The apparent redistribution rate is more rapid following intravascular delivery.

关键词：传输方式血管内传输药物代谢动力学猪动脉疾病

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Effects of viral infection and microbial diversity on patients with sepsis:A retrospective study based on metagenomic next-generation sequencing

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World Journal of Emergency Medicine 2021年第1期12卷 29-35页

作者： Li-wei Duan Jin-long Qu Jian Wan yong-hua xu Yi Shan Li-xue Wu Jin-hao Zheng Wei-wei Jiang Qi-tong Chen Yan Zhu Jian Zhou Wen-bo Yu Lei Pei Xi Song Wen-fang Li Zhao-fen Lin Department of Emergency and Critical Care Medicine Changzheng Hospitalthe Second Military Medical UniversityShanghai 200003China Department of Emergency and Critical Care Medicine Pudong New Area People’s HospitalShanghai 201299China

BACKGROUND: The study aims to investigate the performance of a metagenomic next-generationsequencing (NGS)-based diagnostic technique for the identifi cation of potential bacterial and viral infectionsand eff ects of concomitant viral infection on the survival rate of intensive care unit (ICU) sepsis patients.METHODS: A total of 74 ICU patients with sepsis who were admitted to our institution from February1, 2018 to June 30, 2019 were enrolled. Separate blood samples were collected from patients for bloodcultures and metagenomic NGS when the patients’ body temperature was higher than 38 °C. Patients’demographic data, including gender, age, ICU duration, ICU scores, and laboratory results, were recorded.The correlations between pathogen types and sepsis severity and survival rate were evaluated.RESULTS: NGS produced higher positive results (105 of 118;88.98%) than blood cultures(18 of 118;15.25%) over the whole study period. Concomitant viral infection correlated closelywith sepsis severity and had the negative effect on the survival of patients with sepsis. However,correlation analysis indicated that the bacterial variety did not correlate with the severity of sepsis.CONCLUSIONS: Concurrent viral load correlates closely with the severity of sepsis and thesurvival rate of the ICU sepsis patients. This suggests that prophylactic administration of antiviraldrugs combined with antibiotics may be benefi cial to ICU sepsis patients.

关键词： Sepsis Metagenomic next-generation sequencing Viral infections Bacterial infections Microbial diversity

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Evaluation of suitability,adaptability,and reserve potential of construction land on the Qinghai-Tibet Plateau

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Journal of Geographical Sciences 2024年第1期34卷 41-61页

作者： YANG hua xu yong ZHOU Kan WANG Lijia xu Lin Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Construction land is the leading carrier of human activities such as production and living.Evaluating the construction land suitability(CLS)on the Qinghai-Tibet Plateau(QTP)holds significant implications for harmonizing the relationship between ecological protection and human activity and promoting population and industry layout optimization.However,no relevant studies provide a complete CLS assessment of the QTP.In this study,we developed a model-based CLS evaluation framework coupling of pattern and process to calculate the global CLS on the QTP based on a previously developed CLS evaluation model.Then,using the land-use data of 1990,2000,2010,and 2020,we examined the adaptability of existing construction land(ECL)to the CLS assessment result through the adaptability index and vertical gradient index and further analyzed the limitations of maladaptive construction land.Finally,we calculated the potential area of reserve suitable construction land.This article includes four conclusions:(1)The highly suitable,suitable,moderately suitable,marginally suitable,and unsuitable CLS classes cover areas of 0.33×10^(4)km^(2),10.42×10^(4)km^(2),18.06×10^(4)km^(2),24.12×10^(4)km^(2),and 205.29×10^(4)km^(2),respectively.Only approximately 11%of the study area on the QTP is suitable for large-scale permanent construction land,and approximately 79.50%of the area is unsuitable under current economic and technological conditions.(2)The ECL adaptability index is 85.16%,85.93%,85.18%,and 78.01%during 1990–2020,respectively,with an average adaptability index exceeding 80%on the QTP.The ECL distribution generally conforms to construction land suitable space characteristics but with a significant spatial difference.(3)From 1990 to 2020,the maladaptive ECL was dominated by rural settlement land,transport land,and special land,with a rapidly increasing proportion of urban and other construction land.The maladaptive ECL is constrained by both elevation and slope in the southern Qinghai Plateau,the Hengduan Mountains,and the Qilian Mount

关键词： land resource construction land suitability existing construction land adaptability human activity Qinghai-Tibet Plateau

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Mirizzi syndrome:Problems and strategies

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 234-240页

作者： Jun Wu Shuang-yong Cai xu-Liang Chen Zhi-Tao Chen Shao-hua Shi Department of Hepatobiliary and Pancreatic Surgery People’s Hospital of Jiulongpo DistrictChongqing 400050China Department of Hepatobiliary and Pancreatic Surgery Shulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren University Shulan International Medical CollegeHangzhou 310003China

Mirizzi syndrome is a serious complication of gallstone disease.It is caused by the impacted stones in the gallbladder neck or cystic duct.One of the features of Mirizzi syndrome is severe inflammation or dense fibrosis at the Calot’s triangle.In our clinical practice,bile duct,branches of right hepatic artery and right portal vein clinging to gallbladder infundibulum are often observed due to gallbladder infundibulum adhered to right hepatic hilum.The intraoperative damage of branches of right hepatic artery occurs more easily than that of bile duct,all of which are hidden pitfalls for surgeons.Magnetic resonance cholangiopancreatography(MRCP)and endoscopic retrograde cholangiopancreatography(ERCP)are the preferable tools for the diagnosis of Mirizzi syndrome.Anterograde cholecystectomy in Mirizzi syndrome is easy to damage branches of right hepatic artery and bile duct due to gallbladder infundibulum adhered to right hepatic hilum.Subtotal cholecystectomy is an easy,safe and definitive approach to Mirizzi syndrome.When combined with the application of ERCP,a laparoscopic management of Mirizzi syndrome by well-trained surgeons is feasible and safe.The objective of this review was to highlight its existing problems:(1)low preoperative diagnostic rate,(2)easy to damage bile duct and branches of right hepatic artery,and(3)high concomitant gallbladder carcinoma.Meanwhile,the review aimed to discuss the possible therapeutic strategies:(1)to enhance its preoperative recognition by imaging findings,and(2)to avoid potential pitfalls during surgery.

关键词： Mirizzi syndrome Bile duct injury Artery injury Surgical treatment Subtotal cholecystectomy

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Effects of maternal methyl donor intake during pregnancy on ileum methylation and function in an intrauterine growth restriction pig model

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1173-1189页

作者： Yan Lin Jiangnan Wu yong Zhuo Bin Feng Zhengfeng Fang Shengyu xu Jian Li hua Zhao De Wu Lun hua Lianqiang Che Key Laboratory of Animal Disease‑Resistance Nutrition Animal Nutrition InstituteSichuan Agricultural UniversityChengdu 611130SichuanChina

Background Intrauterine growth retardation(IUGR)affects intestinal growth,morphology,and function,which leads to poor growth performance and high mortality.The present study explored whether maternal dietary methyl donor(MET)supplementation alleviates IUGR and enhances offspring’s growth performance by improving intestinal growth,function,and DNA methylation of the ileum in a porcine IUGR model.Methods Forty multiparous sows were allocated to the control or MET diet groups from mating until delivery.After farrowing,8 pairs of IUGR and normal birth weight piglets from 8 litters were selected for sampling before suckling colostrum.Results The results showed that maternal MET supplementation tended to decrease the IUGR incidence and increased the average weaning weight of piglets.Moreover,maternal MET supplementation significantly reduced the plasma concentrations of isoleucine,cysteine,urea,and total amino acids in sows and newborn pig-lets.It also increased lactase and sucrase activity in the jejunum of newborn piglets.MET addition resulted in lower ileal methionine synthase activity and increased betaine homocysteine S-methyltransferase activity in the ileum of newborn piglets.DNA methylation analysis of the ileum showed that MET supplementation increased the methyla-tion level of DNA CpG sites in the ileum of newborn piglets.Down-regulated differentially methylated genes were enriched in folic acid binding,insulin receptor signaling pathway,and endothelial cell proliferation.In contrast,up-regulated methylated genes were enriched in growth hormone receptor signaling pathway and nitric oxide biosyn-thetic process.Conclusions Maternal MET supplementation can reduce the incidence of IUGR and increase the weaning litter weight of piglets,which may be associated with better intestinal function and methylation status.

关键词： Ileum Intrauterine growth restriction Methyl donor Methylation Sows

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Irisin-loaded electrospun core-shell nanofibers as calvarial periosteum accelerate vascularized bone regeneration by activating the mitochondrial SIRT3 pathway

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Regenerative Biomaterials 2024年第1期3卷 44-57页

作者： Xi hua Mingzhuang Hou Lei Deng Nanning Lv yong xu xuesong Zhu Huilin Yang Qin Shi Hao Liu Fan He Department of Orthopaedics The First Affiliated Hospital of Soochow UniversitySoochow UniversitySuzhou 215006China Orthopaedic Institute Suzhou Medical CollegeSoochow UniversitySuzhou 215000China Department of Orthopedics Suzhou Wuzhong People’s HospitalSuzhouJiangsu Province 215128China Department of Orthopedic Surgery Lianyungang Clinical College of Xuzhou Medical UniversityLianyungang 222003China

The scarcity of native periosteum poses a significant clinical barrier in the repair of critical-sized bone defects.The challenge of enhancing regenerative potential in bone healing is further compounded by oxidative stress at the fracture site.However,the introduction of artificial periosteum has demonstrated its ability to promote bone regeneration through the provision of appropriate mechanical support and controlled release of proosteogenic factors.In this study,a poly(L-lactic acid)(PLLA)/hyaluronic acid(HA)-based nanofibrous membrane was fabricated using the coaxial electrospinning technique.The incorporation of irisin into the core-shell structure of PLLA/HA nanofibers(PLLA/HA@Irisin)achieved its sustained release.In vitro experiments demonstrated that the PLLA/HA@Irisin membranes exhibited favorable biocompatibility.The osteogenic differentiation of bone marrow mesenchymal stem cells(BMMSCs)was improved by PLLA/HA@Irisin,as evidenced by a significant increase in alkaline phosphatase activity and matrix mineralization.Mechanistically,PLLA/HA@Irisin significantly enhanced the mitochondrial function of BMMSCs via the activation of the sirtuin 3 antioxidant pathway.To assess the therapeutic effectiveness,PLLA/HA@Irisin membranes were implanted in situ into critical-sized calvarial defects in rats.The results at 4 and 8 weeks post-surgery indicated that the implantation of PLLA/HA@Irisin exhibited superior efficacy in promoting vascularized bone formation,as demonstrated by the enhancement of bone matrix synthesis and the development of new blood vessels.The results of our study indicate that the electrospun PLLA/HA@Irisin nanofibers possess characteristics of a biomimetic periosteum,showing potential for effectively treating critical-sized bone defects by improving the mitochondrial function and maintaining redox homeostasis of BMMSCs.

关键词： periosteum irisin mitochondrial function critical-sized bone defect redox homeostasis

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Lipid metabolism-related long noncoding RNA RP11-817I4.1 promotes fatty acid synthesis and tumor progression in hepatocellular carcinoma

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World Journal of Gastroenterology 2024年第8期30卷 919-942页

作者： Ren-yong Wang Jia-Ling Yang Ning xu Jia xu Shao-hua Yang Dao-Ming Liang Jin-Ze Li Hong Zhu Second Affiliated Hospital of Kunming Medical University Kunming 650106Yunnan ProvinceChina School of Basic Medical Sciences Nanjing Medical UniversityNanjing 211166Jiangsu ProvinceChina Wuhan Blood Center Wuhan 430030Hubei ProvinceChina Department of Gastrointestinal Surgery The Third People's Hospital of Hubei ProvinceWuhan 430071Hubei ProvinceChina

BACKGROUND Hepatocellular carcinoma(HCC)is one of the most common types of tumors.The influence of lipid metabolism disruption on the development of HCC has been demonstrated in published studies.AIM To establish an HCC prognostic model for lipid metabolism-related long non-coding RNAs(LMR-lncRNAs)and conduct in-depth research on the specific role of novel LMR-lncRNAs in HCC.METHODS Correlation and differential expression analyses of The Cancer Genome Atlas data were used to identify differentially expressed LMR-lncRNAs.Quantitative real-time polymerase chain reaction analysis was used to evaluate the expression of LMR-lncRNAs.Nile red staining was employed to observe intracellular lipid levels.The interaction between RP11-817I4.1,miR-3120-3p,and ATP citrate lyase(ACLY)was validated through the performance of dual-luciferase reporter gene and RIP assays.RESULTS Three LMR-lncRNAs(negative regulator of antiviral response,RNA transmembrane and coiled-coil domain family 1 antisense RNA 1,and RP11-817I4.1)were identified as predictive markers for HCC patients and were utilized in the construction of risk models.Additionally,proliferation,migration,and invasion were reduced by RP11-817I4.1 knockdown.An increase in lipid levels in HCC cells was significantly induced by RP11-817I4.1 through the miR-3120-3p/ACLY axis.CONCLUSION LMR-lncRNAs have the capacity to predict the clinical characteristics and prognoses of HCC patients,and the discovery of a novel LMR-lncRNAs,RP11-817I4.1,revealed its role in promoting lipid accumulation,thereby accelerating the onset and progression of HCC.

关键词： Hepatocellular carcinoma Lipid metabolism Immune microenvironment Prognostic markers Metabolic reprogramming

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Aldehyde oxidase mediated enantioselective metabolic health risk of dinotefuran

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Science China Chemistry 2024年第6期67卷 2079-2091页

作者： Liwei xu Xinxin xu hua Kuang Chuanlai xu Xiaoling Wu State Key Laboratory of Food Science and Resources Jiangnan UniversityWuxi214122China International Joint Research Laboratory for Biointerface and Biodetection and School of Food Science and Technology Jiangnan UniversityWuxi214122China Collaborative Innovation center of Food Safety and Quality Control in Jiangsu Province Jiangnan UniversityWuxi214122China

Chiral pollutants often pose significant differential environmental health risks.In this study,the biotransformation of chiral dinotefuran(DIN)and its enantioselective metabolic toxicity mechanisms have been systemically investigated.Firstly,reversedphase chromatography-high resolution mass spectrometry was developed to quantify the content of DIN R/S chiral enantiomer with pg level sensitivity,revealing a lower elimination rate constant(K_(e))of S-DIN(0.730 h^(-1))than R-DIN(0.746 h^(-1)).Secondly,the interaction mechanism between DIN metabolism and important endogenous bioactive molecules,such as aldehyde oxidase(AOX)and neurotransmitters,was revealed.The DIN nitro-group was converted into a guanidine group by the reducing site of nearby flavin adenine dinucleotide(FAD)in AOX with the preferred higher affinity of S-configuration.Meanwhile,the endogenous tryptophan(Trp)aldehyde metabolic intermediate,5-hydroxyindoleacetaldehyde(5-HIAL),provides a persistent electron donor for DIN reduction via the oxidation-catalyzed site in AOX,resulting in remarkable up-regulation of monoamine neurotransmitters such as serotonin and dopamine.Thirdly,the higher level of neurotransmitters further mediated dysregulation of oxylipin homeostasis via the serotonergic pathway,where S-DIN exhibited more pronounced liver lipid damage and environmental health risk with the accumulated lipid biomarkers,oxidized triglyceride(OxTG)and oxidized sphingomyelin(OxSM).This study elucidates the AOX-mediated enantioselectivity metabolic pathway of DIN,providing a new analytical method for chiral pollutants and paves the way for their health risk assessments.

关键词： neonicotinoid dinotefuran enantiomer aldehyde oxidase metabolomics health risk

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