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Rhodium-Catalyzed Asymmetric Transfer Hydrogenation of Heterocyclic Diaryl Ketones:Facile Access to Key Intermediate of Baloxavir

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Chinese Journal of Chemistry 2024年第1期42卷 43-47页

作者： Li Wang Renwei Xiao Jingyuan Song Long-sheng Zheng Qiwei Lang Gen-Qiang chen Xumu Zhang Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis Department of Chemistryand Medi-PingshanSouthern University of Science and TechnologyShenzhenGuangdong 518000China Academy for Advanced Interdisciplinary Studies Southern Universityof Science and TechnologyShenzhenGuangdong 518000China Chemistry and Chemical Engineering Guangdong Laboratory ShantouGuangdong 515031China

Transition metal-catalyzed asymmetric transfer hydrogenation has been proven to be a powerful approach for the synthesis of chiral alcohols.Herein,a highly efficient and enantioselective transfer hydrogenation of dibenzoheptaheterocyclic ketones catalyzed by an arene-tethered TsDPEN-based Rh(ll)catalyst has been successfully developed,and a variety of dibenzoheptaheterocyclic ketones were reduced by a 1/1 mixture of formic acid and DBU(1,8-diazabicyclo[5.4.0]undec-7-ene)with high yields and enantioselectivities.With this method,the asymmetric reduction of 7,8-difluorodibenzo[b,e]thiepin-11(6H)-one has been realized,providing the key intermediate of baloxavir marboxil with>99% yield and>99% ee at a substrate/catalyst molar ratio of 1000.

关键词： Asymmetric transfer hydrogenation Baloxavir Chiral alcohol Enantioselectivity Heterocyclic diaryl ketone Rhodium(Ⅱ)

Nitrogen–sulfur co-doped porous carbon derived from asphalt as efficient catalyst for oxygen reduction

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Rare Metals 2024年第1期43卷 380-388页

作者： Jing-sheng Ma Ming-Zai Wu Ling chen Li-Xing Zhang Ying Xiong Key Laboratory of Structure and Functional Regulation of Hybrid Materials Ministry of EducationInstitute of EnergyHefei Comprehensive National Science CenterAnhui UniversityHefei 230601China

As an environment-friendly and low-cost petrochemical by-product, asphalt has great potential in the preparation of metal-free oxygen reduction electrocatalysts with excellent performance and outstanding stability. In this paper, we converted asphalt into porous carbon nanosheets by a simple activation method, using potassium citrate as the swelling agent.

关键词： stability porous catalyst

Mitochondrial dysfunction affects hepatic immune and metabolic remodeling in patients with hepatitis B virus-related acute-onchronic liver failure

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World Journal of Gastroenterology 2024年第8期30卷 881-900页

作者： Yu Zhang Xiao-Ling Tian Jie-Qun Li Dong-sheng Wu Qiang Li Bin chen Department of Hepatology Institute of HepatologyThe First Affiliated Hospital of Hunan University of Chinese MedicineChangsha 410021Hunan ProvinceChina Department of Liver Transplant Transplant Medical Research CenterThe Second Xiangya Hospital of Central South UniversityChangsha 410011Hunan ProvinceChina Department of Surgery The First Affiliated Hospital of Hunan University of Chinese MedicineChangsha 410021Hunan ProvinceChina

BACKGROUND Immune dysregulation and metabolic derangement have been recognized as key factors that contribute to the progression of hepatitis B virus(HBV)-related acute-on-chronic liver failure(ACLF).However,the mechanisms underlying immune and metabolic derangement in patients with advanced HBV-ACLF are unclear.AIM To identify the bioenergetic alterations in the liver of patients with HBV-ACLF causing hepatic immune dysregulation and metabolic disorders.METHODS Liver samples were collected from 16 healthy donors(HDs)and 17 advanced HBV-ACLF patients who were eligible for liver transplantation.The mitochondrial ultrastructure,metabolic characteristics,and immune microenvironment of the liver were assessed.More focus was given to organic acid metabolism as well as the function and subpopulations of macrophages in patients with HBV-ACLF.RESULTS Compared with HDs,there was extensive hepatocyte necrosis,immune cell infiltration,and ductular reaction in patients with ACLF.In patients,the liver suffered severe hypoxia,as evidenced by increased expression of hypoxia-inducible factor-1α.Swollen mitochondria and cristae were observed in the liver of patients.The number,length,width,and area of mitochondria were adaptively increased in hepatocytes.Targeted metabolomics analysis revealed that mitochondrial oxidative phosphorylation decreased,while anaerobic glycolysis was enhanced in patients with HBV-ACLF.These findings suggested that,to a greater extent,hepa-tocytes used the extra-mitochondrial glycolytic pathway as an energy source.Patients with HBV-ACLF had elevated levels of chemokine C-C motif ligand 2 in the liver homogenate,which stimulates peripheral monocyte infiltration into the liver.Characterization and functional analysis of macrophage subsets revealed that patients with ACLF had a high abundance of CD68^(+)HLA-DR^(+)macrophages and elevated levels of both interleukin-1βand transforming growth factor-β1 in their livers.The abundance of CD206^(+)CD163^(+)macrophages and expression of interleukin-10 decreased.Th

关键词： Acute-on-chronic liver failure Hypoxia-inducible factor-1α Mitochondria Metabolic phenotype Immune cells

Study on the clogging mechanism of punching screen in sand control by the punching structure parameters

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Petroleum Science 2024年第1期21卷 609-620页

作者： Fu-cheng Deng Fu-Lin Gui Bai-Tao Fan Lei Wen sheng-Hong chen Ning Gong Yun-chen Xiao Zhi-Hui Xu Yangtze University Jingzhou434023HubeiChina CNOOC Research Institute Ltd. Beijing100028China CNOOC Ener Tech-Drilling&Production Co. Tianjin300457China Tianjin Branch of CNOOC Ltd. Tianjin300459China

As an independent sand control unit or a common protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand control pipe which is used in geothermal well or oil and gas well.However,most screens only consider the influence of the internal sand retaining medium parameters in the sand control performance design while ignoring the influence of the plugging of the punching screen on the overall sand retaining performance of the screen.To explore the clogging mechanism of the punching screen,this paper established the clogging mechanism calculation model of a single punching screen sand control unit by using the computational fluid mechanics-discrete element method(CFD-DEM)combined method.According to the combined motion of particles and fluids,the influence of the internal flow state on particle motion and accumulation was analyzed.The results showed that(1)the clogging process of the punching sand control unit is divided into three stages:initial clogging,aggravation of clogging and stability of clogging.In the initial stage of blockage,coarse particles form a loose bridge structure,and blockage often occurs preferentially at the streamline gathering place below chamfering inside the sand control unit.In the stage of blockage intensification,the particle mass develops into a relatively complete sand bridge,which develops from both ends of the opening to the center of the opening.In the stable plugging stage,the sand deposits show a“fan shape”and form a“V-shaped”gully inside the punching slot element.(2)Under a certain reservoir particle-size distribution,The slit length and opening height have a large influence on the permeability and blockage rate,while the slit width size has little influence on the permeability and blockage rate.The microscopic clogging mechanism and its law of the punching screen prevention unit are proposed in this study,which has some field guidance significance for the design of punching screen and sand prevention selection.

关键词： Punching screen Plugging CFD-DEM Size parameter Sand control

Acute upper gastrointestinal bleeding due to portal hypertension in a patient with primary myelofibrosis:A case report

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World Journal of Clinical Cases 2024年第15期12卷 2621-2626页

作者： Yu chen Bing-Bing Kong He Yin Hao Liu sheng Wu Ting Xu Department of Emergency Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China Department of Pathology Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China

BACKGROUND Acute upper gastrointestinal bleeding is a common medical emergency that has a 10%hospital mortality rate.According to the etiology,this disease can be divided into acute varicose veins and nonvaricose veins.Bleeding from esophageal varices is a life-threatening complication of portal hypertension.Portal hypertension is a clinical syndrome defined as a portal venous pressure that exceeds 10 mmHg.Cirrhosis is the most common cause of portal hypertension,and thrombosis of the portal system not associated with liver cirrhosis is the second most common cause of portal hypertension in the Western world.Primary myeloproliferative disorders are the main cause of portal venous thrombosis,and somatic mutations in the Janus kinase 2 gene(JAK2 V617F)can be found in approximately 90% of polycythemia vera,50% of essential thrombocyrosis and 50% of primary myelofibrosis.CASE SUMMARY We present a rare case of primary myelofibrosis with gastrointestinal bleeding as the primary manifestation that presented as portal-superior-splenic mesenteric vein thrombosis.Peripheral blood tests revealed the presence of the JAK2 V617F mutation.Bone marrow biopsy ultimately confirmed the diagnosis of myelofibrosis(MF-2 grade).CONCLUSION In patients with acute esophageal variceal bleeding due to portal hypertension and vein thrombosis without cirrhosis,the possibility of myeloproliferative neoplasms should be considered,and the JAK2 mutation test should be performed.

关键词： Acute esophageal variceal bleeding Portal hypertension Myelofibrosis JAK2 V617F mutation Case report

Gut microbiota induced abnormal amino acids and their correlation with diabetic retinopathy

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 883-895页

作者： sheng-Qun Jiang Su-Na Ye Yin-Hua Huang Yi-Wen Ou Ke-Yang chen Jian-Su chen Shi-Bo Tang Aier Eye Hospital Jinan UniversityGuangzhou 510000Guangdong ProvinceChina Aier Eye Institute and Changsha Aier Hospital Changsha 410000Hunan ProvinceChina The First Affiliated Hospital of Bengbu Medical University Bengbu 233000Anhui ProvinceChina School of Public Health Anhui Medical UniversityHefei 230000Anhui ProvinceChina

AIM:To explore the correlation of gut microbiota and the metabolites with the progression of diabetic retinopathy(DR)and provide a novel strategy to elucidate the pathological mechanism of DR.METHODS:The fecal samples from 32 type 2 diabetes patients with proliferative retinopathy(PDR),23 with nonproliferative retinopathy(NPDR),27 without retinopathy(DM),and 29 from the sex-,age-and BMI-matched healthy controls(29 HC)were analyzed by 16S rDNA gene sequencing.Sixty fecal samples from PDR,DM,and HC groups were assayed by untargeted metabolomics.Fecal metabolites were measured using liquid chromatographymass spectrometry(LC-MS)analysis.Associations between gut microbiota and fecal metabolites were analyzed.RESULTS:A cluster of 2 microbiome and 12 metabolites accompanied with the severity of DR,and the close correlation of the disease progression with PDR-related microbiome and metabolites were found.To be specific,the structure of gut microbiota differed in four groups.Diversity and richness of gut microbiota were significantly lower in PDR and NPDR groups,than those in DM and HC groups.A cluster of microbiome enriched in PDR group,including Pseudomonas,Ruminococcaceae-UCG-002,Ruminococcaceae-UCG-005,Christensenellaceae-R-7,was observed.Functional analysis showed that the glucose and nicotinate degradations were significantly higher in PDR group than those in HC group.Arginine,serine,ornithine,and arachidonic acid were significantly enriched in PDR group,while proline was enriched in HC group.Functional analysis illustrated that arginine biosynthesis,lysine degradation,histidine catabolism,central carbon catabolism in cancer,D-arginine and D-ornithine catabolism were elevated in PDR group.Correlation analysis revealed that Ruminococcaceae-UCG-002 and Christensenellaceae-R-7 were positively associated with L-arginine,ornithine levels in fecal samples.CONCLUSION:This study elaborates the different microbiota structure in the gut from four groups.The relative abundance of Ruminococcaceae-UCG-002 and Parabacteroides are

关键词： proliferative retinopathy gut microbiota Ruminococcaceae amino acid metabolism arginine

Evaluating the Compatibility Mechanism of shengxian Decoction Based on an Excretion Study of 18 Bioactive Constituents in Rat Biosamples

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World Journal of Traditional Chinese Medicine 2024年第1期10卷 40-52页

作者： Tao Pang Nan Weng Yong chen Cui-Yun Huang Mei Sun Feng Zhang Wan-sheng chen Department of Pharmacy Changzheng HospitalNaval Medical University(Second Military Medical University)ShanghaiChina Department of Pharmacognosy Shenyang Pharmaceutical University ShenyangLiaoning ProvinceChina Traditional Chinese Medicine Resource and Technology Center Shanghai University of Traditional Chinese MedicineShanghaiChina

Introduction:The shengxian decoction(SXT),a Chinese herbal medication used to treat heart failure,is composed of Astragali Radix,Anemarrhenae Rhizoma,Bupleuri Radix,Cimicifuage Rhizoma,and Platycodonis Radix.Knowledge of the excretion of the active compounds in this herbal medication is vital for investigating the underlying mechanisms behind its compatibility.However,this remains unclear.Methods:Liquid chromatography coupled with mass spectrometry was performed in both positive and negative modes to assay 18 constituents of SXT from rat urinary,fecal,and biliary samples.Results:The methodology was validated and showed good linearity(r≥0.9),precision,stability,repeatability,and recovery.The relative standard deviations and relative errors for the precision and accuracy did not exceed 15%.The recoveries of all the compounds ranged from 77.37%to 114.82%,and the matrix effect was between 82.53%and 105.71%.The results suggested that,when combined with Platycodonis Radix,the levels of 14 constituents from the four herbs were reduced in the urine,while the levels of six constituents were reduced in the feces.Conclusions:The comparative excretion results indicated that Platycodonis Radix reduced the excretion of compounds in SXT,demonstrating the compatibility mechanism and holistic properties of these compounds,favoring the pharmacological effects of SXT.

关键词： Compatibility excretion liquid chromatography coupled with mass spectrometry Platycodonis Radix shengxian decoction

Understanding the Novel Approach of Nanoferroptosis for Cancer Therapy

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Nano-Micro Letters 2024年第9期16卷 501-556页

作者： Afsana Sheikh Prashant Kesharwani Waleed H.Almalki Salem Salman Almujri Linxin Dai Zhe‑sheng chen Amirhossein Sahebkar Fei Gao Department of Pharmaceutics School of Pharmaceutical Education and ResearchJamia HamdardNew Delhi 110062India Department of Pharmacology and Toxicology Faculty of PharmacyUmm Al-Qura UniversityMakkahSaudi Arabia Department of Pharmacology College of PharmacyKing Khalid University61421 Asir‑AbhaSaudi Arabia State Key Laboratory of Southwestern Chinese Medicine Resources Pharmacy SchoolChengdu University of Traditional Chinese MedicineChengdu 611130People’s Republic of China Department of Pharmaceutical Sciences College of Pharmacy and Health SciencesSt.John’s UniversityNew York 11439USA Biotechnology Research Center Pharmaceutical Technology InstituteMashhad University of Medical SciencesMashhadIran Applied Biomedical Research Center Mashhad University of Medical SciencesMashhadIran

As a new form of regulated cell death,ferroptosis has unraveled the unsolicited theory of intrinsic apoptosis resistance by cancer cells.The molecular mechanism of ferroptosis depends on the induction of oxidative stress through excessive reactive oxygen species accumulation and glutathione depletion to damage the structural integrity of cells.Due to their high loading and structural tunability,nanocarriers can escort the delivery of ferro-therapeutics to the desired site through enhanced permeation or retention effect or by active targeting.This review shed light on the necessity of iron in cancer cell growth and the fascinating features of ferroptosis in regulating the cell cycle and metastasis.Additionally,we discussed the effect of ferroptosis-mediated therapy using nanoplatforms and their chemical basis in overcoming the barriers to cancer therapy.

关键词： Ferroptosis Nanoparticles Ferrotherapy Cancer Genes Nanotechnology Toxicity Reactive oxygen species

Chronological Study of Coal-seam Water and its Implication on Gas Production in the South Qinshui Basin

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 207-219页

作者： chen Biying FANG Lujia LANG Yunchao XU sheng LIU Congqiang ZHANG Luyuan HOU Xiaolin Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China Institute of Earth Environments Chinese Academy of SciencesXi’an 710061China

The knowledge of the residence time of formation water is fundamental to understanding the subsurface flow and hydrological setting.To better identify the origin and evolution of coal seam water and its impact on gas storage and production,this study collected coalbed methane co-produced water in the southeast Qinshui Basin and detected chemical and isotopic compositions,especially 36Cl and 129I concentrations.The calculated tracer ages of 129I(5.2–50.6 Ma)and 36Cl(0.13–0.76 Ma)are significantly younger than the age of coal-bearing formation(Pennsylvanian-Cisuralian),indicating freshwater recharge after coal deposition.The model that utilises 129I/I and 36Cl/Cl ratios to constrain the timing of recharge and the proportion of recharge water reveals that over 60%of pre-anthropogenic meteoric water entered coal seams since 10 Ma and mixed with residue initial deposition water,corresponding to the basin inversion in Cenozoic.The spatial distribution of major ion concentrations reveals the primary recharge pathway for meteoric water from coal outcrops at the eastern margin to the basin center.This study demonstrates the occurrence of higher gas production rates from wells that accept water recharge in recent times and suggests the possible potential of the non-stagnant zones for high gas production.

关键词： CBM co-produced water iodine-129 chlorine-36 water chemistry Qinshui Basin