AIM: To examine the role of p38 during acute experimental cerulein pancreatitis. METHODS: Rats were treated with cerulein with or without a specific JNK inhibitor (CEP1347) and/or a specific p38 inhibitor (SB203580) a...AIM: To examine the role of p38 during acute experimental cerulein pancreatitis. METHODS: Rats were treated with cerulein with or without a specific JNK inhibitor (CEP1347) and/or a specific p38 inhibitor (SB203580) and pancreatic stress kinase activity was determined. Parameters to assess pancreatitis included trypsin, amylase, lipase, pancreatic weight and histology. RESULTS: JNK inhibition with CEP1347 ameliorated pancreatitis, reducing pancreatic edema. In contrast, p38 inhibition with SB203580 aggravated pancreatitis with higher trypsin levels and, with induction of acinar necrosis not normally found after cerulein hyperstimulation. Simultaneous treatment with both CEP1347 and SB203580 mutually abolished the effects of either compound on cerulein pancreatitis. CONCLUSION: Stress kinases modulate pancreatitis differentially. JNK seems to promote pancreatitis development, possibly by supporting inflammatory reactions such as edema formation while its inhibition ameliorates pancreatitis. In contrast, p38 may help reduce organ destruction while inhibition of p38 during induction of cerulein pancreatitis leads to the occurrence of acinar necrosis.展开更多
The production of chlorine by the chlor-alkali process using graphite electrodes was one of the largest sources of polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/PCDFs)in history with estimates in the kg TEQ...The production of chlorine by the chlor-alkali process using graphite electrodes was one of the largest sources of polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/PCDFs)in history with estimates in the kg TEQ range for individual factories.In addition,the chlorine production predecessor processes in the former Leblanc soda factories generated large amounts of PCDD/PCDFs,also in kg TEQ range for individual sites.In both processes coal tar,used as pitch binder for electrodes in the chlor-alkali process or tars for sealing chlorine chambers,was the major source for PCDD/PCDFs formation.The complex PAH mixture in the tars which were chlorinated in the processes contained approx.1%dibenzofuran.Therefore in this study we screened the full range of chlorinated aromatic and heteroaromatic compounds in contaminated soils from former chlor-alkali plants in Germany and Japan as well as from a German Leblanc factory,using high resolution time-of-flight mass spectrometry GC-HR-TOF-MS.At all three sites the full range of unintentionally produced persistent organic pollutants(POPs)listed in the Stockholm Convention(PCDFs,PCDDs,PCBs,PCNs,HCB,HCBD and PeCBz)were present at high ppb levels and TEQ was up to several 100,000 ng/kg soil in hot spot areas.Additionally,a wide range of other polychlorinated(PC-)PAHs(PC-phenanthrene/anthracene,PC-pyrene/fluoranthene,PC-benzo(a)anthracene/chrysene)were detected.Some of these compound classes were present in one to two order of magnitude higher concentrations compared to PCDFs.Furthermore,polychlorinated methyldibenzofurans,polychlorinated dimethyl-/ethyl-dibenzofurans,and polychlorinated carbazoles e the N-analogue of dibenzofuran-were detected at levels comparable to PCDFs at all three sites.Polychlorinated benzonitriles were detected in addition to chlorobenzenes as monoaromatic pollutant.Since all three factories have stopped production 50e120 years ago,all detected chlorinated aromatics can be regarded as very persistent.The technologies have been used in several hundred loca展开更多
A range of bench-stable carbazole-containing hypervalent iodine(Ⅲ) reagents were synthesized by I-N bond formation in good yields.This kind of benziodoxolone reagents was used for a C-N coupling reaction to introduce...A range of bench-stable carbazole-containing hypervalent iodine(Ⅲ) reagents were synthesized by I-N bond formation in good yields.This kind of benziodoxolone reagents was used for a C-N coupling reaction to introduce a carbazole group to aromatic heterocycle compounds.展开更多
The direction of oil charges within a field in the Niger Delta, Nigeria was determined by the sum of differences ranking method of carbazole concentrations after ascertaining other possible geological constraints on t...The direction of oil charges within a field in the Niger Delta, Nigeria was determined by the sum of differences ranking method of carbazole concentrations after ascertaining other possible geological constraints on their compositional variations. The principle is that the smaller the sum, the closer the well to the source kitchen. The approach makes use of carbazoles' interaction with the matrix, which leads to a reduction in their concentration with increasing distance from the source kitchen, allowing prediction of the charging direction. A wide range of compositional variations was observed for C1(806.72–2152.90 lg/g) and C2(767–2469.72 lg/g) carbazoles within the field. Based on these results, we inferred a filling pathway orientation from west to east. This suggests that the source kitchen—the most promising region for oil exploration—is located in the western part of the oil field.展开更多
Polyhalogenated carbazoles(PHCZs)have been widely accepted as emerging pollutants,whereas their ecological and health risks remain uncertain.Herein,female and male Sprague-Dawley(SD)mice were treated with four typical...Polyhalogenated carbazoles(PHCZs)have been widely accepted as emerging pollutants,whereas their ecological and health risks remain uncertain.Herein,female and male Sprague-Dawley(SD)mice were treated with four typical PHCZs to investigate their negative consequences,along with alternations in gutmicrobiota to indicate underlyingmechanisms.In female mice,the relative liver weight ratio increased after four PHCZs exposure;2-bromocarbazole(2-BCZ)increased urine glucose level;3-bromocarbazole(3-BCZ)decreased the glucose and total cholesterol levels;3,6-dichlorocarbazole(3,6-DCCZ)decreased glucose level.The only disturbed biochemical index in male mice was the promoted alkaline phosphatase(ALP)level by 3,6-DCCZ.We also found that the differential blood biochemical indices were correlated with gut microbiota.3-BCZ and 3,6-DCCZ altered Bacteroidetes and Proteobacteria phyla in female and male mice,which were correlated with metabolic disorders.Our findings demonstrated the correlation between PHCZs induced potential hepatotoxicity andmetabolic disordersmay be due to their dioxin-like potentials and endocrine disrupting activities,and the gender differences might result from their estrogenic activities.Overall,data presented here can help to evaluate the ecological and health risks of PHCZs and reveal the underlying mechanisms.展开更多
π-Conjugated polymers(CPs)represent one of the quite important and rapidly growing branches of flexible electrochromic materials.Electrosynthesized hybrid CPs employing dibenzo pentacycles(fluorenes,carbazoles,dibenz...π-Conjugated polymers(CPs)represent one of the quite important and rapidly growing branches of flexible electrochromic materials.Electrosynthesized hybrid CPs employing dibenzo pentacycles(fluorenes,carbazoles,dibenzothiophenes,and dibenzofuran)as the backbones have received considerable attention owing to their special structures and interesting electrochromic performances.Recent studies show that polymers from these structures exhibit decent contrast ratios,favorable coloration efficiencies,low switching voltages,fast response time,excellent stability,and color persistence.Intrinsically,their electrochromic properties significantly depend on fine-tailoring of precursor monomer structures,and polymerization techniques and conditions.This review devotes to showing a clear picture of the research progress of dibenzo pentacycle-centered CPs via electrochemical polymerization,including fluorenes,carbazoles,dibenzothiophenes,and dibenzofuran-based hybrid electrochromic polymers.Critical influences of the tailored precursor structures on their electropolymerization and resultant polymer performances are highlighted,aiming at providing an insight for the development of novel fused ring-based polymer electrochromic materials.展开更多
Polyhalogenated carbazoles(PHCZs)are recently raising much attention due to their toxicity and ubiquitous environmental distribution.However,little knowledge is known about their ambient occurrences and the potential ...Polyhalogenated carbazoles(PHCZs)are recently raising much attention due to their toxicity and ubiquitous environmental distribution.However,little knowledge is known about their ambient occurrences and the potential source.In this study,we developed an analytical method based on GC-MS/MS to simultaneously determine 11 PHCZs in PM_(2.5) from urban Beijing,China.The optimized method provided low method limit of quantifications(MLOQs,1.45–7.39 fg/m^(3))and satisfied recoveries(73.4%–109.5%).This method was applied to analyze the PHCZs in the outdoor PM_(2.5)(n=46)and fly ash(n=6)collected from 3 kinds of surrounding incinerator plants(steel plant,medical waste incinerator and domestic waste incinerator).The levels of Σ_(11)PHCZs in PM_(2.5) ranged from 0.117 to 5.54 pg/m^(3)(median 1.18 pg/m^(3)).3-chloro-9H-carbazole(3-CCZ),3-bromo-9H-carbazole(3-BCZ),and 3,6-dichloro-9Hcarbazole(36-CCZ)were the dominant compounds,accounting for 93%.3-CCZ and 3-BCZ were significantly higher in winter due to the high PM_(2.5) concentration,while 36-CCZ was higher in spring,which may be related to the resuspending of surface soil.Furthermore,the levels of11PHCZs in fly ash ranged from 338 to 6101 pg/g.3-CCZ,3-BCZ and 36-CCZ accounted for 86.0%.The congener profiles of PHCZs between fly ash and PM_(2.5) were highly similar,indicating that combustion process could be an important source of ambient PHCZs.To the best of our knowledge,this is the first research providing the occurrences of PHCZs in outdoor PM_(2.5).展开更多
Bifunctional molecules containing macrocyclic polyamine [12]aneN3 and carbazol units, 1-4, have been efficiently synthe sized and fully characterized. Through gel electrophoresis, atomic force microscopy, and dynamic ...Bifunctional molecules containing macrocyclic polyamine [12]aneN3 and carbazol units, 1-4, have been efficiently synthe sized and fully characterized. Through gel electrophoresis, atomic force microscopy, and dynamic light scattering experiments, compounds 3 and 4b bearing both [12]aneN3 and carbazol moieties showed effective DNA condensation ability at the concen- tration of 80 jaM. Investigations from EB displacement fluorescence spectra, viscosity titration, and ionic strength effects re vealed that the effective DNA condensation comes from the appropriate combination of carbazol and [12]aneN3 units in the bifunctional molecules, and the DNA condensation process is reversible. The incorporation of triazole units in the molecules clearly reduced the cytotoxicity.展开更多
The synthesis of carbazoles based on the electrochemical Pd-catalyzed intramolecular C-H amination of 2-amidobiaryls through oxidative cross coupling has been achieved under mild reaction conditions.The reaction can b...The synthesis of carbazoles based on the electrochemical Pd-catalyzed intramolecular C-H amination of 2-amidobiaryls through oxidative cross coupling has been achieved under mild reaction conditions.The reaction can be carried out in undivided cell without the addition of external chemical oxidant.Besides good functional group compatibility,the desired carbazoles can be scaled up and modified easily.Compared with previous methods,this protocol affords a simple and sustainable avenue for the construction of car-bazoles.展开更多
文摘AIM: To examine the role of p38 during acute experimental cerulein pancreatitis. METHODS: Rats were treated with cerulein with or without a specific JNK inhibitor (CEP1347) and/or a specific p38 inhibitor (SB203580) and pancreatic stress kinase activity was determined. Parameters to assess pancreatitis included trypsin, amylase, lipase, pancreatic weight and histology. RESULTS: JNK inhibition with CEP1347 ameliorated pancreatitis, reducing pancreatic edema. In contrast, p38 inhibition with SB203580 aggravated pancreatitis with higher trypsin levels and, with induction of acinar necrosis not normally found after cerulein hyperstimulation. Simultaneous treatment with both CEP1347 and SB203580 mutually abolished the effects of either compound on cerulein pancreatitis. CONCLUSION: Stress kinases modulate pancreatitis differentially. JNK seems to promote pancreatitis development, possibly by supporting inflammatory reactions such as edema formation while its inhibition ameliorates pancreatitis. In contrast, p38 may help reduce organ destruction while inhibition of p38 during induction of cerulein pancreatitis leads to the occurrence of acinar necrosis.
文摘The production of chlorine by the chlor-alkali process using graphite electrodes was one of the largest sources of polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/PCDFs)in history with estimates in the kg TEQ range for individual factories.In addition,the chlorine production predecessor processes in the former Leblanc soda factories generated large amounts of PCDD/PCDFs,also in kg TEQ range for individual sites.In both processes coal tar,used as pitch binder for electrodes in the chlor-alkali process or tars for sealing chlorine chambers,was the major source for PCDD/PCDFs formation.The complex PAH mixture in the tars which were chlorinated in the processes contained approx.1%dibenzofuran.Therefore in this study we screened the full range of chlorinated aromatic and heteroaromatic compounds in contaminated soils from former chlor-alkali plants in Germany and Japan as well as from a German Leblanc factory,using high resolution time-of-flight mass spectrometry GC-HR-TOF-MS.At all three sites the full range of unintentionally produced persistent organic pollutants(POPs)listed in the Stockholm Convention(PCDFs,PCDDs,PCBs,PCNs,HCB,HCBD and PeCBz)were present at high ppb levels and TEQ was up to several 100,000 ng/kg soil in hot spot areas.Additionally,a wide range of other polychlorinated(PC-)PAHs(PC-phenanthrene/anthracene,PC-pyrene/fluoranthene,PC-benzo(a)anthracene/chrysene)were detected.Some of these compound classes were present in one to two order of magnitude higher concentrations compared to PCDFs.Furthermore,polychlorinated methyldibenzofurans,polychlorinated dimethyl-/ethyl-dibenzofurans,and polychlorinated carbazoles e the N-analogue of dibenzofuran-were detected at levels comparable to PCDFs at all three sites.Polychlorinated benzonitriles were detected in addition to chlorobenzenes as monoaromatic pollutant.Since all three factories have stopped production 50e120 years ago,all detected chlorinated aromatics can be regarded as very persistent.The technologies have been used in several hundred loca
基金supported by the National Key Research and Development Program of China(No.2016YFB0401400)the National Natural Science Foundation of China(Nos.21302139,21672120 and 21871158)the Fok Ying Tong Education Foundation of China(No.151014)。
文摘A range of bench-stable carbazole-containing hypervalent iodine(Ⅲ) reagents were synthesized by I-N bond formation in good yields.This kind of benziodoxolone reagents was used for a C-N coupling reaction to introduce a carbazole group to aromatic heterocycle compounds.
文摘The direction of oil charges within a field in the Niger Delta, Nigeria was determined by the sum of differences ranking method of carbazole concentrations after ascertaining other possible geological constraints on their compositional variations. The principle is that the smaller the sum, the closer the well to the source kitchen. The approach makes use of carbazoles' interaction with the matrix, which leads to a reduction in their concentration with increasing distance from the source kitchen, allowing prediction of the charging direction. A wide range of compositional variations was observed for C1(806.72–2152.90 lg/g) and C2(767–2469.72 lg/g) carbazoles within the field. Based on these results, we inferred a filling pathway orientation from west to east. This suggests that the source kitchen—the most promising region for oil exploration—is located in the western part of the oil field.
基金supported by Joint Innovation Fund for Regional Development of National Natural Science Foundation of China(No.U20A20134)Leading Talent of Technological Innovation of Ten-Thousands Talents Program of Zhejiang Province(No.2020R52012).
文摘Polyhalogenated carbazoles(PHCZs)have been widely accepted as emerging pollutants,whereas their ecological and health risks remain uncertain.Herein,female and male Sprague-Dawley(SD)mice were treated with four typical PHCZs to investigate their negative consequences,along with alternations in gutmicrobiota to indicate underlyingmechanisms.In female mice,the relative liver weight ratio increased after four PHCZs exposure;2-bromocarbazole(2-BCZ)increased urine glucose level;3-bromocarbazole(3-BCZ)decreased the glucose and total cholesterol levels;3,6-dichlorocarbazole(3,6-DCCZ)decreased glucose level.The only disturbed biochemical index in male mice was the promoted alkaline phosphatase(ALP)level by 3,6-DCCZ.We also found that the differential blood biochemical indices were correlated with gut microbiota.3-BCZ and 3,6-DCCZ altered Bacteroidetes and Proteobacteria phyla in female and male mice,which were correlated with metabolic disorders.Our findings demonstrated the correlation between PHCZs induced potential hepatotoxicity andmetabolic disordersmay be due to their dioxin-like potentials and endocrine disrupting activities,and the gender differences might result from their estrogenic activities.Overall,data presented here can help to evaluate the ecological and health risks of PHCZs and reveal the underlying mechanisms.
基金the National Natural Science Foundationof China(51303073,51463008,51572117)the Ganpo Outstanding Talents 555 projects(2013)+4 种基金the National Science Fund for Distinguished Young Scholars in Jiangxi Province,Key Project of Jiangxi Educational Committee(GJJ150795)the Natural Science Foundation of Jiangxi Province(20161BAB216130)Scientific Fund of Jiangxi Science & Technology Normal University(2014QNBJRC003)Jiangxi Science & Technology Normal University Program for Scientific Research Innovation Team (2015CXTD001)Scientific Research Foundation for Doctors in Jiangxi Science & Technology
文摘π-Conjugated polymers(CPs)represent one of the quite important and rapidly growing branches of flexible electrochromic materials.Electrosynthesized hybrid CPs employing dibenzo pentacycles(fluorenes,carbazoles,dibenzothiophenes,and dibenzofuran)as the backbones have received considerable attention owing to their special structures and interesting electrochromic performances.Recent studies show that polymers from these structures exhibit decent contrast ratios,favorable coloration efficiencies,low switching voltages,fast response time,excellent stability,and color persistence.Intrinsically,their electrochromic properties significantly depend on fine-tailoring of precursor monomer structures,and polymerization techniques and conditions.This review devotes to showing a clear picture of the research progress of dibenzo pentacycle-centered CPs via electrochemical polymerization,including fluorenes,carbazoles,dibenzothiophenes,and dibenzofuran-based hybrid electrochromic polymers.Critical influences of the tailored precursor structures on their electropolymerization and resultant polymer performances are highlighted,aiming at providing an insight for the development of novel fused ring-based polymer electrochromic materials.
基金supported by the National Key Research and Development Program of China(Nos.2018YFA0901104 and 2019YFE0111100)the National Natural Science Foundation of China(No.91743206)the Special Project of Eco-Environmental Technology for Peak Carbon Dioxide Emissions and Carbon Neutrality(No.RCEES-TDZ-2021-23).
文摘Polyhalogenated carbazoles(PHCZs)are recently raising much attention due to their toxicity and ubiquitous environmental distribution.However,little knowledge is known about their ambient occurrences and the potential source.In this study,we developed an analytical method based on GC-MS/MS to simultaneously determine 11 PHCZs in PM_(2.5) from urban Beijing,China.The optimized method provided low method limit of quantifications(MLOQs,1.45–7.39 fg/m^(3))and satisfied recoveries(73.4%–109.5%).This method was applied to analyze the PHCZs in the outdoor PM_(2.5)(n=46)and fly ash(n=6)collected from 3 kinds of surrounding incinerator plants(steel plant,medical waste incinerator and domestic waste incinerator).The levels of Σ_(11)PHCZs in PM_(2.5) ranged from 0.117 to 5.54 pg/m^(3)(median 1.18 pg/m^(3)).3-chloro-9H-carbazole(3-CCZ),3-bromo-9H-carbazole(3-BCZ),and 3,6-dichloro-9Hcarbazole(36-CCZ)were the dominant compounds,accounting for 93%.3-CCZ and 3-BCZ were significantly higher in winter due to the high PM_(2.5) concentration,while 36-CCZ was higher in spring,which may be related to the resuspending of surface soil.Furthermore,the levels of11PHCZs in fly ash ranged from 338 to 6101 pg/g.3-CCZ,3-BCZ and 36-CCZ accounted for 86.0%.The congener profiles of PHCZs between fly ash and PM_(2.5) were highly similar,indicating that combustion process could be an important source of ambient PHCZs.To the best of our knowledge,this is the first research providing the occurrences of PHCZs in outdoor PM_(2.5).
基金supported by the Program for New Century Excellent Talents in Universities(NCET-08-0054)the National Natural Science Foundation of China(20972019)
文摘Bifunctional molecules containing macrocyclic polyamine [12]aneN3 and carbazol units, 1-4, have been efficiently synthe sized and fully characterized. Through gel electrophoresis, atomic force microscopy, and dynamic light scattering experiments, compounds 3 and 4b bearing both [12]aneN3 and carbazol moieties showed effective DNA condensation ability at the concen- tration of 80 jaM. Investigations from EB displacement fluorescence spectra, viscosity titration, and ionic strength effects re vealed that the effective DNA condensation comes from the appropriate combination of carbazol and [12]aneN3 units in the bifunctional molecules, and the DNA condensation process is reversible. The incorporation of triazole units in the molecules clearly reduced the cytotoxicity.
基金This work was supported by the National Natural Science Foundation of China(No.21520102003)the Hubei Province Natural Science Foundation of China(No.2017CFA010).The Program of Introducing Talents of Discipline to Universities of China(111 Program)is also appreciated.
文摘The synthesis of carbazoles based on the electrochemical Pd-catalyzed intramolecular C-H amination of 2-amidobiaryls through oxidative cross coupling has been achieved under mild reaction conditions.The reaction can be carried out in undivided cell without the addition of external chemical oxidant.Besides good functional group compatibility,the desired carbazoles can be scaled up and modified easily.Compared with previous methods,this protocol affords a simple and sustainable avenue for the construction of car-bazoles.
