In December 2019, a new type viral pneumonia cases occurred in Wuhan, Hubei Province;and then named "2019 novel coronavirus(2019-nCoV)" by the World Health Organization(WHO) on 12 January 2020. For it is a n...In December 2019, a new type viral pneumonia cases occurred in Wuhan, Hubei Province;and then named "2019 novel coronavirus(2019-nCoV)" by the World Health Organization(WHO) on 12 January 2020. For it is a never been experienced respiratory disease before and with infection ability widely and quickly, it attracted the world’s attention but without treatment and control manual. For the request from frontline clinicians and public health professionals of 2019-nCoV infected pneumonia management, an evidence-based guideline urgently needs to be developed. Therefore, we drafted this guideline according to the rapid advice guidelines methodology and general rules of WHO guideline development;we also added the first-hand management data of Zhongnan Hospital of Wuhan University. This guideline includes the guideline methodology, epidemiological characteristics, disease screening and population prevention, diagnosis, treatment and control(including traditional Chinese Medicine), nosocomial infection prevention and control, and disease nursing of the 2019-nCoV. Moreover, we also provide a whole process of a successful treatment case of the severe 2019-nCoV infected pneumonia and experience and lessons of hospital rescue for 2019-nCoV infections. This rapid advice guideline is suitable for the first frontline doctors and nurses, managers of hospitals and healthcare sections, community residents, public health persons, relevant researchers, and all person who are interested in the 2019-nCoV.展开更多
The important supporting component in a gas turbine is the casing,which has the characteristics of large size,complex structure,and thin wall.In the context of existing 3DP sand casting processes,casting crack defects...The important supporting component in a gas turbine is the casing,which has the characteristics of large size,complex structure,and thin wall.In the context of existing 3DP sand casting processes,casting crack defects are prone to occur.This leads to an increase in the scrap rate of casings,causing significant resource wastage.Additionally,the presence of cracks poses a significant safety hazard after the casings are put into service.The generation of different types of crack defects in stainless steel casings is closely related to casting stress and the high-temperature concession of the sand mold.Therefore,the types and causes of cracks in stainless steel casing products,based on their structural characteristics,were systematically analyzed.Various sand molds with different internal topology designs were printed using the 3DP technology to investigate the impact of sand mold structures on high-temperature concession.The optimal sand mold structure was used to cast casings,and the crack suppression effect was verified by analyzing its eddy current testing results.The experimental results indicate that the skeleton structure has an excellent effect on suppressing cracks in the casing.This research holds important theoretical and engineering significance in improving the quality of casing castings and reducing production costs.展开更多
Ten novel isocoumarins,including four pairs of enantiomers,were isolated from Artemisia dubia var.subdigitata(Asteraceae).Compounds 1,2 and 3a/3b possessed a unique 6/6/6-tricyclic system comprising an unusual 1-(2-me...Ten novel isocoumarins,including four pairs of enantiomers,were isolated from Artemisia dubia var.subdigitata(Asteraceae).Compounds 1,2 and 3a/3b possessed a unique 6/6/6-tricyclic system comprising an unusual 1-(2-methylcyclohexyl)propan-1-one moiety fused with isocoumarin core skeleton.Compounds 4a/4b were characterized as an unexpected 2,5-dimethylcyclohexan-1-one scaffold,and compounds 5a/5b and 6a/6b were rare 1,2-seco-isocoumarin.Their structures and absolute configurations were elucidated through spectroscopic data,X-ray crystallography,ECD and NMR calculations with DP4+analyses.Plausible biosynthetic pathways were proposed from the naturally occurring isocoumarin.Network pharmacological analysis suggested that the targets of compound 1 were significantly enriched in the cell cycle and Pl3K-Akt signaling pathway.The molecular docking revealed that compound 1 had high binding affinity with CDK2(total score:6.8717).Furthermore,compounds 1 and 2 exhibited inhibitory activity on three human hepatoma cell lines,with inhibitory ratios of 85.1% and 84.5%(HepG2),88.2% and 87.3%(Huh7),and 69.2% and 69.1%(SK-Hep-1)at 200μmol·L^(-1),respectively.展开更多
17 new guaiane-type sesquiterpenoid dimers(GSDs),artemzhongdianolides B1—B17(1—17),were isolated from Artemisia zhongdianensis under the guidance of bioassay,and elucidated by spectral analyses(HRESIMS,1D and 2D NMR...17 new guaiane-type sesquiterpenoid dimers(GSDs),artemzhongdianolides B1—B17(1—17),were isolated from Artemisia zhongdianensis under the guidance of bioassay,and elucidated by spectral analyses(HRESIMS,1D and 2D NMR,IR,ECD).The absolute configuration of compounds 1,3,7,9,10,and 13 was determined by single-crystal X-ray diffraction analyses.Structurally,artemzhongdianolides B1(1)and B2(2)were the first example of the GSDs fused via a C-13/C-13'single bond,and artemzhongdianolides B3—B17 were[4+2]Diels–Alder adducts of two monomeric guaianolides.Most of the compounds showed antihepatoma cytotoxicity with IC_(50) values ranging from 9.9 to 170.1μmol/L.Importantly,artemzhongdianolide B9(9)was the most active one against three hepatoma cell lines with IC_(50) values of 13.1μmol/L(HepG2),19.5μmol/L(Huh7),and 19.5μmol/L(SK-Hep-1),and dose-dependently inhibited cell migration and invasion,induced G1 cell cycle arrest and cell apoptosis in HepG2 cells.Compound 9 might suppress HepG2 cells via affecting the p38MAPK signaling pathway suggested by machine learning approach,and significantly upregulated expression of phosphorylated p38 validated by Western blot assay.展开更多
Mentha haplocalyx(Mentha canadensis)is widely used as a medicinal plant in traditional Chinese medicine,and the extracts of its aerial parts are found to signifcantly inhibit the activity ofα-glucosidase with an IC_(...Mentha haplocalyx(Mentha canadensis)is widely used as a medicinal plant in traditional Chinese medicine,and the extracts of its aerial parts are found to signifcantly inhibit the activity ofα-glucosidase with an IC_(50) value of 21.0μg/mL.Bioactivity-guided isolation of the extracts aforded two new compounds(1 and 2),together with 23 known ones(3-25).Their structures were established by extensive spectroscopic analyses(1D and 2D NMR,MS,IR and UV).Compounds 1-17 and 21-25 were evaluated for theirα-glucosidase inhibitory activities.Compound 11 was the most active ones with an IC_(50) values of 83.4μM.These results verify theα-glucosidase inhibitory activity of M.haplocalyx(M.canadensis)and specify its active compounds for the frst time.展开更多
Controlled peptide assembly offers significant promise to develop synthetic supramolecular nanostructures to display material and biological properties that mimic protein assemblies in nature.Despite the progress in f...Controlled peptide assembly offers significant promise to develop synthetic supramolecular nanostructures to display material and biological properties that mimic protein assemblies in nature.Despite the progress in forming peptide nanostructures of various morphology,there exists a distinct gap between natural and synthetic assembly systems in terms of size control.Constructing nanostructures with a narrow size distribution that can be tuned over a wide range of length-scales is essential for applications that require precise spacing between objects.This approach provides the opportunity to correlate materials and biological properties of interest with assembly size.In this review,we discuss representative endeavors over the past two decades for design of size-controllable peptide nanostructures using tunable building blocks.Other mechanisms for size control,e.g.,molecular frustration,template-directed peptide assembly,and multi-component peptide co-assembly,will also be discussed.We also demonstrate the applicable scopes of these strategies and suggest potential future avenues for scientific advances in this field.展开更多
A detailed understanding of the distribution and potential of natural gas hydrate(NGHs)resources is crucial to fostering the industrialization of those resources in the South China Sea,where NGHs are abundant.In this ...A detailed understanding of the distribution and potential of natural gas hydrate(NGHs)resources is crucial to fostering the industrialization of those resources in the South China Sea,where NGHs are abundant.In this study,this study analyzed the applicability of resource evaluation methods,including the volumetric,genesis,and analogy methods,and estimated NGHs resource potential in the South China Sea by using scientific resource evaluation methods based on the factors controlling the geological accumulation and the reservoir characteristics of NGHs.Furthermore,this study compared the evaluation results of NGHs resource evaluations in representative worldwise sea areas via rational analysis.The results of this study are as follows:(1)The gas hydrate accumulation in the South China Sea is characterized by multiple sources of gas supply,multi-channel migration,and extensive accumulation,which are significantly different from those of oil and gas and other unconventional resources.(2)The evaluation of gas hydrate resources in the South China Sea is a highly targeted,stratified,and multidisciplinary evaluation of geological resources under the framework of a multi-type gas hydrate resource evaluation system and focuses on the comprehensive utilization of multi-source heterogeneous data.(3)Global NGHs resources is n×10^(15)m^(3),while the NGHs resources in the South China Sea are estimated to be 10^(13)m^(3),which is comparable to the abundance of typical marine NGHs deposits in other parts of the world.In the South China Sea,the NGHs resources have a broad prospect and provide a substantial resource base for production tests and industrialization of NGHs.展开更多
Nineteen new cadinane-involving sesquiterpenoid dimers,artemordins A-S(1-—19),together with 13 known SDs(20-32)were isolated from Artemisia ordosica.Their structures and absolute configurations were established by co...Nineteen new cadinane-involving sesquiterpenoid dimers,artemordins A-S(1-—19),together with 13 known SDs(20-32)were isolated from Artemisia ordosica.Their structures and absolute configurations were established by comprehensive spectral analyses,X-ray single crystal diffraction,theoretical ECD,and NMR calculations.Chemically,artemordins A-F(1—6)were the first examples of two cadinane units constructed by unprecedented C-3−C-15′or C-3−C-13′single bond with an oxido-rearranged 6/5/6/6 fused ring system;artemordins G-K(7-11)were biogenetically connected by[4+2]cycloaddition reaction and artemordins G-J(7-10)possessed a novel 5/6/6/6/6/6/5-heptacyclic fused ring system.Artemordins L-S(12-19)were formed by esterification,which involved three different types of sesquiterpenoids.Antihepatoma assay suggested that the most active compounds,artemordins B and H(2 and 8),exhibited inhibitory activities on three hepatoma cell lines with IC50 values of 26.9 and 25.1μmol/L(HepG2),29.5 and 18.3μmol/L(Huh7),19.7 and 15.7μmol/L(SK-Hep-1).展开更多
Three new phenolics（1–3） and twenty-eight known compounds（4–31） were isolated from an ethanolic extract of roots of Alangium chinense. Compound 11 exhibited antiviral activity against Coxsackie virus B3 with IC5...Three new phenolics（1–3） and twenty-eight known compounds（4–31） were isolated from an ethanolic extract of roots of Alangium chinense. Compound 11 exhibited antiviral activity against Coxsackie virus B3 with IC50 values of 16.89 mmol/L. Compounds 1, 10–17, 19–21, and 23 showed strong antioxidant activity against Fe^2＋-cysteine-induced rat liver microsomal lipid peroxidation, with IC50 values of 0.14–8.18 mmol/L.展开更多
Inspired by the intriguing structures and remarkable activities of sesquiterpenoid dimers,12 new sesquiterpenoid dimers,artematrovirenolides A—D(1—4)and artematrolides S—Z(8—12),were isolated from the EtOAc fracti...Inspired by the intriguing structures and remarkable activities of sesquiterpenoid dimers,12 new sesquiterpenoid dimers,artematrovirenolides A—D(1—4)and artematrolides S—Z(8—12),were isolated from the EtOAc fraction of Artemisia atrovirens through a bioactivity-guided approach.Their structures were elucidated by comprehensive spectroscopic data and absolute configuration was assigned based on single crystal X-ray diffraction data and ECD calculations.Structurally,all compounds are presumably formed via[4+2]cycloaddition involving three connecting model.Compounds 1—4 are four novel hetero-dimeric[4+2]Diels-Alder adducts dimerized from a rotundane-type unit and a guaiane-type monomer,and compounds 5—12 are eight new homo-dimeric[4+2]adducts derived from two guaianolide moieties.A putative biosynthetic pathway for compounds 1—4 was also proposed.Compounds 4,6,7,and 10 demonstrated moderate cytotoxicity against HepG2,SMMC-7721,and Huh7 cell lines with IC50 values ranging from 9.3 to 62.3μmol/L.Interestingly,compounds 5 and 11 manifested cytotoxicity with IC50 values of 13.6 and 12.8(HepG2),18.5 and 13.1(SMMC-7721),and 16.5 and 19.4μmol/L(Huh7),respectively,which were equivalent to the positive control,sorafenib.This investigation suggests that compounds 5 and 11 might be considered as potent antihepatoma candidates and deserve further structural modification and mechanism study.展开更多
Eleven new secoiridoid aglycones involving unusual C9-skeleton:swerimilegenins A-F(1-6);bis-C9-skeleton:swerimilegenin G(7);and C_(10)-skeleton:swerimilegenins H−K(8−11),as well as six known ones,were isolated from th...Eleven new secoiridoid aglycones involving unusual C9-skeleton:swerimilegenins A-F(1-6);bis-C9-skeleton:swerimilegenin G(7);and C_(10)-skeleton:swerimilegenins H−K(8−11),as well as six known ones,were isolated from the low-polarity part of the traditional Chinese herb medicine Swertia mileensis.Their structures were determined by extensive spectroscopic data and X-ray diffraction.Biogenetically,swerimilegenin A(1)belonged to 10-nor-secoiridoid,and swerimilegenins B-F(2-6)were 1-nor-secoiridoids.Erythrocentaurin(12)and gentiogenal(15)showed moderate anti-HBV activity on HepG 2.2.15 cell line in vitro.展开更多
Artemiprincepsolides A-F(1-6)were isolated from Artemisia princeps guided by bioactivity and elucidated by comprehensive spectral data and ECD calculation.Compounds 1-3 represented the first connecting model of germac...Artemiprincepsolides A-F(1-6)were isolated from Artemisia princeps guided by bioactivity and elucidated by comprehensive spectral data and ECD calculation.Compounds 1-3 represented the first connecting model of germacrane-guaiane hetero-dimeric adducts,and compounds 4-6 were eudesmane-guaiane hetero-coupled sesquiterpenoid dimers,meanwhile,all these were presumably formed by Diels-Alder cycloaddition.Compounds 1-6 were evaluated for their hepatomatic cytotoxicity on three hepatoma cell lines,and demonstrated cytotoxicity with IC_(50)values in the range of 5.0-67.3μmol/L.Interestingly,compound 1 manifested significant cytotoxicity against HepG2,Huh7,and SK-Hep-1 cells with IC_(50)values of 9.9,9.2,and 5.0μmol/L,which were almost equivalent to the positive control,sorafenib.Flow cytometry data and Western blot assays revealed the most active compound 1 dose-dependently inhibited cell migration and invasion,and significantly induced HepG2 cells arrest in G2/M phase by downregulating proteins pcdc2 and upregulating the level of protein CyclinB1;and induced apoptosis by downregulating of Bcl-2 expression and upregulating Bax level.展开更多
A thermochemical model based on the ion and molecule coexistence theory(IMCT)was developed to calculate thermodynamic data in the CaO-SiO_(2)-Al_(2)O_(3) slag system,considering the influential role of oxide activitie...A thermochemical model based on the ion and molecule coexistence theory(IMCT)was developed to calculate thermodynamic data in the CaO-SiO_(2)-Al_(2)O_(3) slag system,considering the influential role of oxide activities on the thermodynamic properties of slags.Using this model,iso-activity contours were obtained for oxide components CaO,SiO_(2) and Al2O3 in this system at temperatures of 1,873 K and 1,773 K.When compared with the IMCT model,it is found that the predicted activities of oxide components in the CaO-SiO_(2)-Al_(2)O_(3) system using the model developed in this study better matches experimental data from literature in terms of both trend and numerical value.Therefore,the model developed in this study can serve as a robust modeling tool for metallurgical processes,and the thermodynamic data predicted by this new model can be used to improve the metallurgical technology.展开更多
基金supported(in part)by the Entrusted Project of National Center for Medical Service Administration,National Health and Family Planning Commission China(No.[2019]099)the First Level Funding of the Second Medical Leading Talent Project in Hubei Provincethe Special Project for Emergency of the Ministry of Science and Technology(2020YFC0841300)。
文摘In December 2019, a new type viral pneumonia cases occurred in Wuhan, Hubei Province;and then named "2019 novel coronavirus(2019-nCoV)" by the World Health Organization(WHO) on 12 January 2020. For it is a never been experienced respiratory disease before and with infection ability widely and quickly, it attracted the world’s attention but without treatment and control manual. For the request from frontline clinicians and public health professionals of 2019-nCoV infected pneumonia management, an evidence-based guideline urgently needs to be developed. Therefore, we drafted this guideline according to the rapid advice guidelines methodology and general rules of WHO guideline development;we also added the first-hand management data of Zhongnan Hospital of Wuhan University. This guideline includes the guideline methodology, epidemiological characteristics, disease screening and population prevention, diagnosis, treatment and control(including traditional Chinese Medicine), nosocomial infection prevention and control, and disease nursing of the 2019-nCoV. Moreover, we also provide a whole process of a successful treatment case of the severe 2019-nCoV infected pneumonia and experience and lessons of hospital rescue for 2019-nCoV infections. This rapid advice guideline is suitable for the first frontline doctors and nurses, managers of hospitals and healthcare sections, community residents, public health persons, relevant researchers, and all person who are interested in the 2019-nCoV.
基金financially supported by the National Natural Science Foundation of China(No.52175352)the Xing Liao Ying Cai Project of Liaoning Province(No.XLYC2008036)the Shenyang Youth Innovation Talent Support Program(No.RC220429)。
文摘The important supporting component in a gas turbine is the casing,which has the characteristics of large size,complex structure,and thin wall.In the context of existing 3DP sand casting processes,casting crack defects are prone to occur.This leads to an increase in the scrap rate of casings,causing significant resource wastage.Additionally,the presence of cracks poses a significant safety hazard after the casings are put into service.The generation of different types of crack defects in stainless steel casings is closely related to casting stress and the high-temperature concession of the sand mold.Therefore,the types and causes of cracks in stainless steel casing products,based on their structural characteristics,were systematically analyzed.Various sand molds with different internal topology designs were printed using the 3DP technology to investigate the impact of sand mold structures on high-temperature concession.The optimal sand mold structure was used to cast casings,and the crack suppression effect was verified by analyzing its eddy current testing results.The experimental results indicate that the skeleton structure has an excellent effect on suppressing cracks in the casing.This research holds important theoretical and engineering significance in improving the quality of casing castings and reducing production costs.
基金financially supported by the Key Program of the National Natural Science Foundation of China(22137008)the Xingdian Yingcai Project(YNWR-KJLJ-2019-002)+1 种基金the Youth Innovation Promotion Association,CAs(2020386)the Reserve Talents of Young and Middle-aged Academic and Technical Leaders in Yunnan Province(202105AC160021).
文摘Ten novel isocoumarins,including four pairs of enantiomers,were isolated from Artemisia dubia var.subdigitata(Asteraceae).Compounds 1,2 and 3a/3b possessed a unique 6/6/6-tricyclic system comprising an unusual 1-(2-methylcyclohexyl)propan-1-one moiety fused with isocoumarin core skeleton.Compounds 4a/4b were characterized as an unexpected 2,5-dimethylcyclohexan-1-one scaffold,and compounds 5a/5b and 6a/6b were rare 1,2-seco-isocoumarin.Their structures and absolute configurations were elucidated through spectroscopic data,X-ray crystallography,ECD and NMR calculations with DP4+analyses.Plausible biosynthetic pathways were proposed from the naturally occurring isocoumarin.Network pharmacological analysis suggested that the targets of compound 1 were significantly enriched in the cell cycle and Pl3K-Akt signaling pathway.The molecular docking revealed that compound 1 had high binding affinity with CDK2(total score:6.8717).Furthermore,compounds 1 and 2 exhibited inhibitory activity on three human hepatoma cell lines,with inhibitory ratios of 85.1% and 84.5%(HepG2),88.2% and 87.3%(Huh7),and 69.2% and 69.1%(SK-Hep-1)at 200μmol·L^(-1),respectively.
基金supported by the Key Program of National Natural Science Foundation of China(22137008)the Xingdian Yingcai Project(YNWR-KJLJ-2019-002)+1 种基金the Youth Innovation Promotion Association,CAS(2020386)the Reserve Talents of Young and Middle-aged Academic and Technical Leaders in Yunnan Province(202105AC160021).
文摘17 new guaiane-type sesquiterpenoid dimers(GSDs),artemzhongdianolides B1—B17(1—17),were isolated from Artemisia zhongdianensis under the guidance of bioassay,and elucidated by spectral analyses(HRESIMS,1D and 2D NMR,IR,ECD).The absolute configuration of compounds 1,3,7,9,10,and 13 was determined by single-crystal X-ray diffraction analyses.Structurally,artemzhongdianolides B1(1)and B2(2)were the first example of the GSDs fused via a C-13/C-13'single bond,and artemzhongdianolides B3—B17 were[4+2]Diels–Alder adducts of two monomeric guaianolides.Most of the compounds showed antihepatoma cytotoxicity with IC_(50) values ranging from 9.9 to 170.1μmol/L.Importantly,artemzhongdianolide B9(9)was the most active one against three hepatoma cell lines with IC_(50) values of 13.1μmol/L(HepG2),19.5μmol/L(Huh7),and 19.5μmol/L(SK-Hep-1),and dose-dependently inhibited cell migration and invasion,induced G1 cell cycle arrest and cell apoptosis in HepG2 cells.Compound 9 might suppress HepG2 cells via affecting the p38MAPK signaling pathway suggested by machine learning approach,and significantly upregulated expression of phosphorylated p38 validated by Western blot assay.
基金supported by the CAS Hundred Talents Program,the Youth Innovation Promotion Association of the Chinese Academy of Sciences(CN),and Southeast Asia Biodiversity Research Institute,CAS(2017CASSEABRIQG003).
文摘Mentha haplocalyx(Mentha canadensis)is widely used as a medicinal plant in traditional Chinese medicine,and the extracts of its aerial parts are found to signifcantly inhibit the activity ofα-glucosidase with an IC_(50) value of 21.0μg/mL.Bioactivity-guided isolation of the extracts aforded two new compounds(1 and 2),together with 23 known ones(3-25).Their structures were established by extensive spectroscopic analyses(1D and 2D NMR,MS,IR and UV).Compounds 1-17 and 21-25 were evaluated for theirα-glucosidase inhibitory activities.Compound 11 was the most active ones with an IC_(50) values of 83.4μM.These results verify theα-glucosidase inhibitory activity of M.haplocalyx(M.canadensis)and specify its active compounds for the frst time.
基金supported by the National Natural Science Foundation of China(Nos.22074128 and 22241503)Fundamental Research Funds for the Central Universities(Nos.20720210013 and 20720220005).
文摘Controlled peptide assembly offers significant promise to develop synthetic supramolecular nanostructures to display material and biological properties that mimic protein assemblies in nature.Despite the progress in forming peptide nanostructures of various morphology,there exists a distinct gap between natural and synthetic assembly systems in terms of size control.Constructing nanostructures with a narrow size distribution that can be tuned over a wide range of length-scales is essential for applications that require precise spacing between objects.This approach provides the opportunity to correlate materials and biological properties of interest with assembly size.In this review,we discuss representative endeavors over the past two decades for design of size-controllable peptide nanostructures using tunable building blocks.Other mechanisms for size control,e.g.,molecular frustration,template-directed peptide assembly,and multi-component peptide co-assembly,will also be discussed.We also demonstrate the applicable scopes of these strategies and suggest potential future avenues for scientific advances in this field.
基金jointly supported by the National Natural Science Foundation of China(42376222,U22A20581,and 42076069)Key Research and Development Program of Hainan Province(ZDYF2024GXJS002)China Geological Survey(DD20230402)。
文摘A detailed understanding of the distribution and potential of natural gas hydrate(NGHs)resources is crucial to fostering the industrialization of those resources in the South China Sea,where NGHs are abundant.In this study,this study analyzed the applicability of resource evaluation methods,including the volumetric,genesis,and analogy methods,and estimated NGHs resource potential in the South China Sea by using scientific resource evaluation methods based on the factors controlling the geological accumulation and the reservoir characteristics of NGHs.Furthermore,this study compared the evaluation results of NGHs resource evaluations in representative worldwise sea areas via rational analysis.The results of this study are as follows:(1)The gas hydrate accumulation in the South China Sea is characterized by multiple sources of gas supply,multi-channel migration,and extensive accumulation,which are significantly different from those of oil and gas and other unconventional resources.(2)The evaluation of gas hydrate resources in the South China Sea is a highly targeted,stratified,and multidisciplinary evaluation of geological resources under the framework of a multi-type gas hydrate resource evaluation system and focuses on the comprehensive utilization of multi-source heterogeneous data.(3)Global NGHs resources is n×10^(15)m^(3),while the NGHs resources in the South China Sea are estimated to be 10^(13)m^(3),which is comparable to the abundance of typical marine NGHs deposits in other parts of the world.In the South China Sea,the NGHs resources have a broad prospect and provide a substantial resource base for production tests and industrialization of NGHs.
基金This work was financially supported by the Key Program of National Natural Science Foundation of China(22137008)the Xingdian Yingcai Project(YNWR-KJLJ-2019-002)+4 种基金the Youth Innovation Promotion Association,CAS(2020386)the Reserve Talents of Young and Middle-aged Academic and Technical Leaders in Yunnan Province(202105AC160021)the High-Level Talent Program of Yunnan Province(YNQR-QNRC-2020-125)the Science and Technology Plan Projects in Yunnan Province(202201AT070143)State Key Laboratory of Phytochemistry and Plant Resources in West China(P2021-ZZ06).
文摘Nineteen new cadinane-involving sesquiterpenoid dimers,artemordins A-S(1-—19),together with 13 known SDs(20-32)were isolated from Artemisia ordosica.Their structures and absolute configurations were established by comprehensive spectral analyses,X-ray single crystal diffraction,theoretical ECD,and NMR calculations.Chemically,artemordins A-F(1—6)were the first examples of two cadinane units constructed by unprecedented C-3−C-15′or C-3−C-13′single bond with an oxido-rearranged 6/5/6/6 fused ring system;artemordins G-K(7-11)were biogenetically connected by[4+2]cycloaddition reaction and artemordins G-J(7-10)possessed a novel 5/6/6/6/6/6/5-heptacyclic fused ring system.Artemordins L-S(12-19)were formed by esterification,which involved three different types of sesquiterpenoids.Antihepatoma assay suggested that the most active compounds,artemordins B and H(2 and 8),exhibited inhibitory activities on three hepatoma cell lines with IC50 values of 26.9 and 25.1μmol/L(HepG2),29.5 and 18.3μmol/L(Huh7),19.7 and 15.7μmol/L(SK-Hep-1).
基金supported by the National Science and Technology Project of China (No. 2009ZX09311-004)the National Natural Science Foundation of China (No. 201072234)
文摘Three new phenolics（1–3） and twenty-eight known compounds（4–31） were isolated from an ethanolic extract of roots of Alangium chinense. Compound 11 exhibited antiviral activity against Coxsackie virus B3 with IC50 values of 16.89 mmol/L. Compounds 1, 10–17, 19–21, and 23 showed strong antioxidant activity against Fe^2＋-cysteine-induced rat liver microsomal lipid peroxidation, with IC50 values of 0.14–8.18 mmol/L.
基金supported by the Key Program of National Natural Science Foundation of China(22137008)Yunnan Wanren Project(YNWR-KJLJ-2019-002).
文摘Inspired by the intriguing structures and remarkable activities of sesquiterpenoid dimers,12 new sesquiterpenoid dimers,artematrovirenolides A—D(1—4)and artematrolides S—Z(8—12),were isolated from the EtOAc fraction of Artemisia atrovirens through a bioactivity-guided approach.Their structures were elucidated by comprehensive spectroscopic data and absolute configuration was assigned based on single crystal X-ray diffraction data and ECD calculations.Structurally,all compounds are presumably formed via[4+2]cycloaddition involving three connecting model.Compounds 1—4 are four novel hetero-dimeric[4+2]Diels-Alder adducts dimerized from a rotundane-type unit and a guaiane-type monomer,and compounds 5—12 are eight new homo-dimeric[4+2]adducts derived from two guaianolide moieties.A putative biosynthetic pathway for compounds 1—4 was also proposed.Compounds 4,6,7,and 10 demonstrated moderate cytotoxicity against HepG2,SMMC-7721,and Huh7 cell lines with IC50 values ranging from 9.3 to 62.3μmol/L.Interestingly,compounds 5 and 11 manifested cytotoxicity with IC50 values of 13.6 and 12.8(HepG2),18.5 and 13.1(SMMC-7721),and 16.5 and 19.4μmol/L(Huh7),respectively,which were equivalent to the positive control,sorafenib.This investigation suggests that compounds 5 and 11 might be considered as potent antihepatoma candidates and deserve further structural modification and mechanism study.
基金This work was funded by the National Natural Science Foundation of China and Yunnan Province(U0832603)the National Science Foundation of China for Distinguished Young Scholars(81025023)+1 种基金the West Light Foundation of the Chinese Academy of Sciences,the International Foundation for Science(No.F/5202-1)the Youth Innovation Promotion Association,CAS.
文摘Eleven new secoiridoid aglycones involving unusual C9-skeleton:swerimilegenins A-F(1-6);bis-C9-skeleton:swerimilegenin G(7);and C_(10)-skeleton:swerimilegenins H−K(8−11),as well as six known ones,were isolated from the low-polarity part of the traditional Chinese herb medicine Swertia mileensis.Their structures were determined by extensive spectroscopic data and X-ray diffraction.Biogenetically,swerimilegenin A(1)belonged to 10-nor-secoiridoid,and swerimilegenins B-F(2-6)were 1-nor-secoiridoids.Erythrocentaurin(12)and gentiogenal(15)showed moderate anti-HBV activity on HepG 2.2.15 cell line in vitro.
基金This work was financially supported by the Key Program of the National Natural Science Foundation of China(22137008)the Xingdian Yingcai Project(YNWR-KJLJ-2019-002)+1 种基金the Youth Innovation Promotion Association,CAS(2020386)the Reserve Talents of Young and Middle-aged Academic and Technical Leaders in YunnanProvince(202105AC160021).
文摘Artemiprincepsolides A-F(1-6)were isolated from Artemisia princeps guided by bioactivity and elucidated by comprehensive spectral data and ECD calculation.Compounds 1-3 represented the first connecting model of germacrane-guaiane hetero-dimeric adducts,and compounds 4-6 were eudesmane-guaiane hetero-coupled sesquiterpenoid dimers,meanwhile,all these were presumably formed by Diels-Alder cycloaddition.Compounds 1-6 were evaluated for their hepatomatic cytotoxicity on three hepatoma cell lines,and demonstrated cytotoxicity with IC_(50)values in the range of 5.0-67.3μmol/L.Interestingly,compound 1 manifested significant cytotoxicity against HepG2,Huh7,and SK-Hep-1 cells with IC_(50)values of 9.9,9.2,and 5.0μmol/L,which were almost equivalent to the positive control,sorafenib.Flow cytometry data and Western blot assays revealed the most active compound 1 dose-dependently inhibited cell migration and invasion,and significantly induced HepG2 cells arrest in G2/M phase by downregulating proteins pcdc2 and upregulating the level of protein CyclinB1;and induced apoptosis by downregulating of Bcl-2 expression and upregulating Bax level.
基金This work was financially supported by the National Natural Science Foundation of China(NSFC 52175352).
文摘A thermochemical model based on the ion and molecule coexistence theory(IMCT)was developed to calculate thermodynamic data in the CaO-SiO_(2)-Al_(2)O_(3) slag system,considering the influential role of oxide activities on the thermodynamic properties of slags.Using this model,iso-activity contours were obtained for oxide components CaO,SiO_(2) and Al2O3 in this system at temperatures of 1,873 K and 1,773 K.When compared with the IMCT model,it is found that the predicted activities of oxide components in the CaO-SiO_(2)-Al_(2)O_(3) system using the model developed in this study better matches experimental data from literature in terms of both trend and numerical value.Therefore,the model developed in this study can serve as a robust modeling tool for metallurgical processes,and the thermodynamic data predicted by this new model can be used to improve the metallurgical technology.
