Molecularly imprinted polymers(MIPs)are a kind of synthetic receptors possessing wide application prospects in proteins recognition.However,there are still great challenges in proteins imprinting due to their large si...Molecularly imprinted polymers(MIPs)are a kind of synthetic receptors possessing wide application prospects in proteins recognition.However,there are still great challenges in proteins imprinting due to their large size and easy conformation change.In this study,we explored epitope-oriented MIP based on host-vip interaction(hg-MIP)and constructed a novel hg-MIP-SERS(surface-enhanced Raman scatting)approach for efficiently recognizing the terminal epitopes of neuron-specific enolase(NSE),a well-known disease biomarker for small cell lung cancer,neuroblstom,and Alzheimer's disease.The C-and N-terminal epitopes of NSE were modified with 4-(phenylazo)benzoic acid,then they were used as the templates and immobilized onβ-cyclodextrin-functionalized substrates.The imprinted layer was formed by polymerization of various functional monomers.Combined with SERS detection,an antibody-free sandwich assay based on hg-MIP was successfully used to detect the concentration of NSE in human serums,with the advantages of simple operation,small sample volume(5μL),wide linear range(1–10^(4)ng/m L)and a limit of detection as low as 0.01 ng/m L.The developed epitope-oriented hg-MIP-SERS approach can also be extended to other proteins,expanding the imprinting method of proteins,and has a broad development space in the field of protein separation and detection.展开更多
BACKGROUND Silicosis is a type of chronic pulmonary fibrosis caused by long-term inhalation of silica dust particles.There has been no ideal biomarker for the diagnosis and differential diagnosis of silicosis until no...BACKGROUND Silicosis is a type of chronic pulmonary fibrosis caused by long-term inhalation of silica dust particles.There has been no ideal biomarker for the diagnosis and differential diagnosis of silicosis until now.Studies have found that elevated neuron-specific enolase(NSE)concentration in the serum of silicosis patients is helpful for diagnosis and severity assessment of the disease.However,the number of cases in these studies was not enough to arouse attention.AIM To investigate the clinical significance of serum NSE in the diagnosis and staging of silicosis.METHODS From January 2017 to June 2019,326 cases of silicosis confirmed in Quanzhou First Hospital Affiliated to Fujian Medical University were included in the silicosis group.A total of 328 healthy individuals or medical patients without silicosis were included in the control group.Serum NSE concentrations of all subjects were determined by electrochemical luminescence.RESULTS There were no significant differences in sex,age,smoking index and complications between the silicosis and control groups.The mean serum NSE concentration was 26.57±20.95 ng/mL in the silicosis group and 12.42±2.68 ng/mL in the control group.The difference between the two groups was significant(U=15187,P=0.000).Among the 326 patients with silicosis,103 had stage I silicosis,and the mean serum NSE concentration was 15.55±6.23 ng/mL.The mean serum NSE concentration was 21.85±12.05 ng/mL in 70 patients with stage II silicosis.The mean serum NSE concentration was 36.14±25.72 ng/mL in 153 patients with stage III silicosis.Kruskal-Wallis H test suggested that the difference in serum NSE concentration in silicosis patients in the three groups was significant(H=130.196,P=0.000).Receiver operating characteristic curve analysis indicated that the area under the curve was 0.858(95%confidence interval:0.828-0.888;P=0.000).When the NSE concentration was 15.82 ng/mL,the Jorden index was the largest,the sensitivity was 72%,and the specificity was 90%.CONCLUSION Serum NSE concentration may be a promising biomarker for the diagnosis and assessment of severity of silicosis.展开更多
BACKGROUND： Previous studies have shown that transplantation of vascular endothelial growth factor （VEGF）-modified neural stem cells （NSC） provides better outcomes, compared with neural stem cells, in the treatme...BACKGROUND： Previous studies have shown that transplantation of vascular endothelial growth factor （VEGF）-modified neural stem cells （NSC） provides better outcomes, compared with neural stem cells, in the treatment of brain damage. OBJECTIVE： To compare the effects of VEGF-modified NSC transplantation and NSC transplantation on radiation-induced brain injury, and to determine neuron-specific enolase （NSE） expression in the brain. DESIGN, TIME, AND SETTING： The randomized, controlled study was performed at the Linbaixin Experimental Center, Second Affiliated Hospital, Sun Yat-sen University, China from November 2007 to October 2008. MATERIALS： VEGF-modified C17.2 NSCs were supplied by Harvard Medical School, USA. Streptavidin-biotin-peroxidase-complex kit （Boster, China） and 5, 6-carboxyfluorescein diacetate succinimidyl ester （Fluka, USA） were used in this study. METHODS： A total of 84 Sprague Dawley rats were randomly assigned to a blank control group （n = 20）, model group （n = 20）, NSC group （n = 20）, and a VEGF-modified NSC group （n = 24）. Rat models of radiation-induced brain injury were established in the model, NSC, and VEGF-modified NSC groups. At 1 week following model induction, 10 pL （5 ×10^4 cells/μL） VEGF-modified NSCs or NSCs were respectively infused into the striatum and cerebral cortex of rats from the VEGF-modified NSC and NSC groups. A total of 10μL saline was injected into rats from the blank control and model groups. MAIN OUTCOME MEASURES： NSE expression in the brain was detected by immunohistochemistry following VEGF-modified NSC transplantation. RESULTS： NSE expression was significantly decreased in the brains of radiation-induced brain injury rats （P 〈 0.05）. The number of NSE-positive neurons significantly increased in the NSC and VEGF-modified NSC groups, compared with the model group （P 〈 0.05）. NSE expression significantly increased in the VEGF-modified NSC group, compared with the NSC group, at 6 weeks following transplantation （P 〈 0.05）. CONCLUSION： VEGF-modified NSC transplantation increased NSE expression in rats with radiation-induced brain injury, and the outcomes were superior to NSC transplantation.展开更多
BACKGROUND： Calcium antagonists may act as neuroprotectants, diminishing the influx of calcium ions through voltage-sensitive calcium channels. When administered prophylactically, they display neuroprotective effects...BACKGROUND： Calcium antagonists may act as neuroprotectants, diminishing the influx of calcium ions through voltage-sensitive calcium channels. When administered prophylactically, they display neuroprotective effects against hypoxic-ischemic brain damage in newborn rats. OBJECTIVE： To investigate the neuroprotective effects of flunarizine （FNZ）, lamotrigine （LTG） and the combination of both drugs, on hypoxic-ischemic brain damage in fetal rats. DESIGN AND SETTING： This randomized, complete block design was performed at the Department of Pediatrics, Shenzhen Fourth People＇s Hospital, Guangdong Medical College. MATERIALS： Forty pregnant Wistar rats, at gestational day 20, were selected for the experiment and were randomly divided into FNZ, LTG, FNZ ＋ LTG, and model groups, with 10 rats in each group. METHODS： Rats in the FNZ, LTG, and FNZ ＋ LTG groups received intragastric injections of FNZ （0.5 mg/kg/d）, LTG （10 mg/kg/d）, and FNZ （0.5 mg/kg/d） ＋ LTG （10 mg/kg/d）, respectively. Drugs were administered once a day for 3 days prior to induction of hypoxia-ischemia. Rats in the model group were not administered any drugs. Three hours after the final administration, eight pregnant rats from each group underwent model establishment hypoxia-ischemia brain damage to the fetal rats. Cesareans were performed at 6, 12, 24, and 48 hours later; and 5 fetal rats were removed from each mother and kept warm. Two fetuses without model establishment were removed by planned cesarean at the same time and served as controls. A total of 0.3 mL serum was collected from fetal rats at 6, 12, 24, and 48 hours, respectively, following birth. MAIN OUTCOME MEASURES： Serum protein concentrations of neuron-specific enolase and S-100 were measured by ELISA. Serum concentrations of brain-specific creatine kinase were measured using an electrogenerated chemiluminescence method. RESULTS： Serum concentrations of neuron-specific enolase, S-100, and brain-specific creatine kinase were significantly higher in the hypoxic-ischemic fetal rats, compared with the non-hypoxic-ischemic group. Serum concentrations of neuron-specific enolase, S-100, and brain-specific creatine kinase were significantly less in the FNZ, LTG, and FNZ ＋ LTG groups following ischemia, compared with the model group （P 〈 0.01）. However, these values were significantly greater in the FNZ and LTG groups, compared with the FNZ ＋ LTG group, following ischemia （P 〈 0.01）. CONCLUSION： Preventive antenatal use of oral FNZ and LTG has positive neuroprotective effects on intrauterine hypoxic-ischemic brain damage. The combined effect of these two drugs is superior.展开更多
Spirotetramat metabolizes to its active enol form in the plant. We described here a photocaged pesticide delivery system that can release insecticidal spirotetramat enol form upon light irradiation. Covalently linking...Spirotetramat metabolizes to its active enol form in the plant. We described here a photocaged pesticide delivery system that can release insecticidal spirotetramat enol form upon light irradiation. Covalently linking spirotetramat-enol with photoresponsive coumarin generated the caged insecticide. The photophysical and photochemical properties, deprotection photolysis and insecticidal activities of the caged spirotetramat enol were studied. This light-triggered system can undergo cleavage to release free spirotetramat enol form at the presence of blue light （420 nm） or sunlight, Bioassays indicated that the triggered molecule has no obvious insecticidal activity against Aphis craccivora Koch at dark and could be activated by light to release the insecticidal ingredients, which provides precise control over insecticide delivery.展开更多
Keto-enol tautomers of curcumin were confirmed by reversed-phase liquid chromatography（RPLC）/ hybrid quadrupole ion trap/time-of-flight mass spectrometry（QIT/TOFMS）.Tautomers gave different MS/MS spectra in negati...Keto-enol tautomers of curcumin were confirmed by reversed-phase liquid chromatography（RPLC）/ hybrid quadrupole ion trap/time-of-flight mass spectrometry（QIT/TOFMS）.Tautomers gave different MS/MS spectra in negative mode.Different mass spectra were also obtained by hydrogen/deuterium exchange LC/MS/MS in positive mode.Our results suggest that enol form is the major form in the solution（water/acetonitrile）.展开更多
A domino reaction of anilines with cyclic and acyclic enol ethers induced by catalytic amounts of TBPA^（·＋）（5 mol%） was investigated and a series of 2,4-disubstituted-1,2,3,4-tetrahydroquinolines were synthe...A domino reaction of anilines with cyclic and acyclic enol ethers induced by catalytic amounts of TBPA^（·＋）（5 mol%） was investigated and a series of 2,4-disubstituted-1,2,3,4-tetrahydroquinolines were synthesized.Different from cyclic enol ethers, when acyclic enol ethers were used in the reaction,they serve as surrogates of acetaldehyde,producing a series of 2-methyl-4- anilino-1,2,3,4-tetrahydroquinolines.A single electron transfer mechanism was proposed to rationalize the products formation.展开更多
The nucleophilic addition of Ti(IV) enolate derived from methyl aryl ketones to α, β–unsaturated compounds was found to be highly selective to give 1, 2 addition products.
Regioselective addition reactions of silyl enolates to a, b-unsaturated aldehyde and its acetal catalyzed by MgI2 etherate give aldol adducts (1, 2-addition) preferentially over Michael adducts (1, 4-addition). This ...Regioselective addition reactions of silyl enolates to a, b-unsaturated aldehyde and its acetal catalyzed by MgI2 etherate give aldol adducts (1, 2-addition) preferentially over Michael adducts (1, 4-addition). This unique regioselectivity is distinctly different with other Lewis acidic promoters and may be attributed to the high oxyphilicity of IMg+.展开更多
Substituent, temperature and solvent effects on tautomeric equilibria in several β-ketoamides have been investigated by means of nuclear magnetic resonance spectroscopy (NMR). Keto-enol equilibrium predominates over ...Substituent, temperature and solvent effects on tautomeric equilibria in several β-ketoamides have been investigated by means of nuclear magnetic resonance spectroscopy (NMR). Keto-enol equilibrium predominates over the amide-imidol one. The relative stability of the individual tautomers and the corresponding equilibrium shifts are explained considering electronic and steric effects and tautomer stabilization via internal hydrogen bonds. In solution, these compounds exist mainly as ketoamide and Z-enolamide tautomers, both presenting intramolecular hydrogen bonds.展开更多
Purpose:Mild traumatic brain injury(TBI)is common but accurate diagnosis and its clinical consequences have been a problem.Maxillofacial trauma does have an association with TBI.Neuron-specific enolase(NSE)has been de...Purpose:Mild traumatic brain injury(TBI)is common but accurate diagnosis and its clinical consequences have been a problem.Maxillofacial trauma does have an association with TBI.Neuron-specific enolase(NSE)has been developed to evaluate neuronl damage.The objective of this study was to investigate the accuracy of NSE serum levels to detect mild brain injury of patients with sustained maxillofacial fractures during motor vehicle accidents.Methods:Blood samples were drawn from 40 healthy people(control group)and 48 trauma patients who has sustained isolated maxillofacial fractures and mild brain injury in motor vehicle accidents.Brain injuries were graded by Glasgow Coma Scale.In the trauma group,correlations between the NSE serum value and different facial fracture sites were also assessed.Results:The NSE serum level(mean±SD,ng/ml)in the 48 patients with maxillofacial fractures and mild TBI was 13.12±9.68,significantly higher than that measured in the healthy control group(7.72±1.82,p<0.001).The mean NSE serum level(ng/ml)in the lower part of the facial skeleton(15.44 with SD 15.34)was higher than that in the upper facial part(12.42 with SD 7.68);and the mean NSE level(ng/ml)in the middle-and lower part(11.97 with SD 5.63)was higher than in the middle part(7.88 with SD 2.64).Conclusion:An increase in NSE serum levels can be observed in patients sustained maxillofacial fractures and mild brain injury.展开更多
Neuron-specific enolase (NSE) levels of cerebrospinal fluid (CSF) were measured in 39 patients with ischemic stroke and 15 controls. There was a significant increase of CSF NSE in acute ischemic stroke patients as com...Neuron-specific enolase (NSE) levels of cerebrospinal fluid (CSF) were measured in 39 patients with ischemic stroke and 15 controls. There was a significant increase of CSF NSE in acute ischemic stroke patients as compared with the controls. The altered CSF NSE levels correlated well with the infarct size in CT scan. The CSF NSE levels were higher in 6-multiinfarct dementia (MID) patients who were diagnosed after 6-month follow-up than those in 22 non-MID patients of this series. Our research supports the view that CSF NSE can be a useful biochemical marker for brain ischemia. The importance of CSF NSE in the study of dementia related to ischemic stroke is worth further studies.展开更多
Background:The Cre/loxP system is most popular in mice,but its application in rats has largely lagged far behind.The rat is vital laboratory animal,especially in toxicological and neurological studies.Generating genet...Background:The Cre/loxP system is most popular in mice,but its application in rats has largely lagged far behind.The rat is vital laboratory animal,especially in toxicological and neurological studies.Generating genetic tools to manipulate neurons in rats could benefit neurological research.Methods:Using the CRISPR/Cas9 system,we inserted a Cre cassette into endogenous Thy1 and NeuN loci.Thy1-Cre rats featured a downstream P2A-linked insertion,while NeuN-Cre was inserted at the transcriptional start site.The Cre activity was assessed by crossing with a Cre reporter(Rosa26 imCherry)rat and through analyzing mCherry expression patterns.The specificity of cell type was further confirmed by immunofluorescence with NeuN antibody.Phenotypic consequences were assessed by crossing with ND1^(LSL) rats to deplete ND1,followed by monitoring weight/survival and conducting motor function tests.Results:We generated two neuron-specific rats(Thy1-Cre and NeuN-Cre),which exhibited high neuron-specific Cre expression in brain and spinal cord with minor leakage in other tissues.Thy1-Cre showed minor leakage in spleen,lung and kidney while NeuN-Cre showed minor leakage in spleen and kidney.ND1^(Thy1-Cre) and ND1^(NeuN-Cre) rats both showed decreased body weights and survival times.The ND1^(NeuN-Cre) rats died within two weeks,while ND1^(Thy1-Cre) rats lived longer with impaired motor function.Conclusions:We successfully generated two neuron-specific NeuN-Cre and Thy1-Cre rats,and systemically analyzed their expression pattern.展开更多
基金supported by Open Project of State Key Laboratory of Supramolecular Structure and Materials,Jilin University,China(No.sklssm2024018)。
文摘Molecularly imprinted polymers(MIPs)are a kind of synthetic receptors possessing wide application prospects in proteins recognition.However,there are still great challenges in proteins imprinting due to their large size and easy conformation change.In this study,we explored epitope-oriented MIP based on host-vip interaction(hg-MIP)and constructed a novel hg-MIP-SERS(surface-enhanced Raman scatting)approach for efficiently recognizing the terminal epitopes of neuron-specific enolase(NSE),a well-known disease biomarker for small cell lung cancer,neuroblstom,and Alzheimer's disease.The C-and N-terminal epitopes of NSE were modified with 4-(phenylazo)benzoic acid,then they were used as the templates and immobilized onβ-cyclodextrin-functionalized substrates.The imprinted layer was formed by polymerization of various functional monomers.Combined with SERS detection,an antibody-free sandwich assay based on hg-MIP was successfully used to detect the concentration of NSE in human serums,with the advantages of simple operation,small sample volume(5μL),wide linear range(1–10^(4)ng/m L)and a limit of detection as low as 0.01 ng/m L.The developed epitope-oriented hg-MIP-SERS approach can also be extended to other proteins,expanding the imprinting method of proteins,and has a broad development space in the field of protein separation and detection.
基金Supported by Quanzhou Science and Technology Bureau,No.2018N053S.
文摘BACKGROUND Silicosis is a type of chronic pulmonary fibrosis caused by long-term inhalation of silica dust particles.There has been no ideal biomarker for the diagnosis and differential diagnosis of silicosis until now.Studies have found that elevated neuron-specific enolase(NSE)concentration in the serum of silicosis patients is helpful for diagnosis and severity assessment of the disease.However,the number of cases in these studies was not enough to arouse attention.AIM To investigate the clinical significance of serum NSE in the diagnosis and staging of silicosis.METHODS From January 2017 to June 2019,326 cases of silicosis confirmed in Quanzhou First Hospital Affiliated to Fujian Medical University were included in the silicosis group.A total of 328 healthy individuals or medical patients without silicosis were included in the control group.Serum NSE concentrations of all subjects were determined by electrochemical luminescence.RESULTS There were no significant differences in sex,age,smoking index and complications between the silicosis and control groups.The mean serum NSE concentration was 26.57±20.95 ng/mL in the silicosis group and 12.42±2.68 ng/mL in the control group.The difference between the two groups was significant(U=15187,P=0.000).Among the 326 patients with silicosis,103 had stage I silicosis,and the mean serum NSE concentration was 15.55±6.23 ng/mL.The mean serum NSE concentration was 21.85±12.05 ng/mL in 70 patients with stage II silicosis.The mean serum NSE concentration was 36.14±25.72 ng/mL in 153 patients with stage III silicosis.Kruskal-Wallis H test suggested that the difference in serum NSE concentration in silicosis patients in the three groups was significant(H=130.196,P=0.000).Receiver operating characteristic curve analysis indicated that the area under the curve was 0.858(95%confidence interval:0.828-0.888;P=0.000).When the NSE concentration was 15.82 ng/mL,the Jorden index was the largest,the sensitivity was 72%,and the specificity was 90%.CONCLUSION Serum NSE concentration may be a promising biomarker for the diagnosis and assessment of severity of silicosis.
基金Supported by:the National Natural Science Foundation of China,No.30870750the Doctor Priming Program of Natural Foundation of Guangdong Province,No. 8451008901000672+1 种基金the Medical Scientific Research Foundation Program of Guangdong Province,No. B2008044the Youth Teacher Foundation Program of Sun Yat-sen University, No,3177915
文摘BACKGROUND： Previous studies have shown that transplantation of vascular endothelial growth factor （VEGF）-modified neural stem cells （NSC） provides better outcomes, compared with neural stem cells, in the treatment of brain damage. OBJECTIVE： To compare the effects of VEGF-modified NSC transplantation and NSC transplantation on radiation-induced brain injury, and to determine neuron-specific enolase （NSE） expression in the brain. DESIGN, TIME, AND SETTING： The randomized, controlled study was performed at the Linbaixin Experimental Center, Second Affiliated Hospital, Sun Yat-sen University, China from November 2007 to October 2008. MATERIALS： VEGF-modified C17.2 NSCs were supplied by Harvard Medical School, USA. Streptavidin-biotin-peroxidase-complex kit （Boster, China） and 5, 6-carboxyfluorescein diacetate succinimidyl ester （Fluka, USA） were used in this study. METHODS： A total of 84 Sprague Dawley rats were randomly assigned to a blank control group （n = 20）, model group （n = 20）, NSC group （n = 20）, and a VEGF-modified NSC group （n = 24）. Rat models of radiation-induced brain injury were established in the model, NSC, and VEGF-modified NSC groups. At 1 week following model induction, 10 pL （5 ×10^4 cells/μL） VEGF-modified NSCs or NSCs were respectively infused into the striatum and cerebral cortex of rats from the VEGF-modified NSC and NSC groups. A total of 10μL saline was injected into rats from the blank control and model groups. MAIN OUTCOME MEASURES： NSE expression in the brain was detected by immunohistochemistry following VEGF-modified NSC transplantation. RESULTS： NSE expression was significantly decreased in the brains of radiation-induced brain injury rats （P 〈 0.05）. The number of NSE-positive neurons significantly increased in the NSC and VEGF-modified NSC groups, compared with the model group （P 〈 0.05）. NSE expression significantly increased in the VEGF-modified NSC group, compared with the NSC group, at 6 weeks following transplantation （P 〈 0.05）. CONCLUSION： VEGF-modified NSC transplantation increased NSE expression in rats with radiation-induced brain injury, and the outcomes were superior to NSC transplantation.
基金Shenzhen Science and Technology Bureau, No.200405204
文摘BACKGROUND： Calcium antagonists may act as neuroprotectants, diminishing the influx of calcium ions through voltage-sensitive calcium channels. When administered prophylactically, they display neuroprotective effects against hypoxic-ischemic brain damage in newborn rats. OBJECTIVE： To investigate the neuroprotective effects of flunarizine （FNZ）, lamotrigine （LTG） and the combination of both drugs, on hypoxic-ischemic brain damage in fetal rats. DESIGN AND SETTING： This randomized, complete block design was performed at the Department of Pediatrics, Shenzhen Fourth People＇s Hospital, Guangdong Medical College. MATERIALS： Forty pregnant Wistar rats, at gestational day 20, were selected for the experiment and were randomly divided into FNZ, LTG, FNZ ＋ LTG, and model groups, with 10 rats in each group. METHODS： Rats in the FNZ, LTG, and FNZ ＋ LTG groups received intragastric injections of FNZ （0.5 mg/kg/d）, LTG （10 mg/kg/d）, and FNZ （0.5 mg/kg/d） ＋ LTG （10 mg/kg/d）, respectively. Drugs were administered once a day for 3 days prior to induction of hypoxia-ischemia. Rats in the model group were not administered any drugs. Three hours after the final administration, eight pregnant rats from each group underwent model establishment hypoxia-ischemia brain damage to the fetal rats. Cesareans were performed at 6, 12, 24, and 48 hours later; and 5 fetal rats were removed from each mother and kept warm. Two fetuses without model establishment were removed by planned cesarean at the same time and served as controls. A total of 0.3 mL serum was collected from fetal rats at 6, 12, 24, and 48 hours, respectively, following birth. MAIN OUTCOME MEASURES： Serum protein concentrations of neuron-specific enolase and S-100 were measured by ELISA. Serum concentrations of brain-specific creatine kinase were measured using an electrogenerated chemiluminescence method. RESULTS： Serum concentrations of neuron-specific enolase, S-100, and brain-specific creatine kinase were significantly higher in the hypoxic-ischemic fetal rats, compared with the non-hypoxic-ischemic group. Serum concentrations of neuron-specific enolase, S-100, and brain-specific creatine kinase were significantly less in the FNZ, LTG, and FNZ ＋ LTG groups following ischemia, compared with the model group （P 〈 0.01）. However, these values were significantly greater in the FNZ and LTG groups, compared with the FNZ ＋ LTG group, following ischemia （P 〈 0.01）. CONCLUSION： Preventive antenatal use of oral FNZ and LTG has positive neuroprotective effects on intrauterine hypoxic-ischemic brain damage. The combined effect of these two drugs is superior.
基金financially supported by the National Natural Science Foundation of China (Nos. 21472046, 21372079)Science and Technology Commission of Shanghai Municipality (No. 16391902300)the Fundamental Research Funds for the Central Universities (No. 222201718004)
文摘Spirotetramat metabolizes to its active enol form in the plant. We described here a photocaged pesticide delivery system that can release insecticidal spirotetramat enol form upon light irradiation. Covalently linking spirotetramat-enol with photoresponsive coumarin generated the caged insecticide. The photophysical and photochemical properties, deprotection photolysis and insecticidal activities of the caged spirotetramat enol were studied. This light-triggered system can undergo cleavage to release free spirotetramat enol form at the presence of blue light （420 nm） or sunlight, Bioassays indicated that the triggered molecule has no obvious insecticidal activity against Aphis craccivora Koch at dark and could be activated by light to release the insecticidal ingredients, which provides precise control over insecticide delivery.
基金supported by the Research Fund for the Doctoral Program of Higher Education(No.20110002110052)
文摘Keto-enol tautomers of curcumin were confirmed by reversed-phase liquid chromatography（RPLC）/ hybrid quadrupole ion trap/time-of-flight mass spectrometry（QIT/TOFMS）.Tautomers gave different MS/MS spectra in negative mode.Different mass spectra were also obtained by hydrogen/deuterium exchange LC/MS/MS in positive mode.Our results suggest that enol form is the major form in the solution（water/acetonitrile）.
基金We thank NSFC(No.21002079)Project(No.20096203120002)supported by the Ministry of Education of the People's Republic of China.We also thank the third Knowledge and Technological Innovation Project(No.NWNUKJCXGC -03-75 and NWNU-KJCXGC-03-64) of Northwest Normal University for supporting our research
文摘A domino reaction of anilines with cyclic and acyclic enol ethers induced by catalytic amounts of TBPA^（·＋）（5 mol%） was investigated and a series of 2,4-disubstituted-1,2,3,4-tetrahydroquinolines were synthesized.Different from cyclic enol ethers, when acyclic enol ethers were used in the reaction,they serve as surrogates of acetaldehyde,producing a series of 2-methyl-4- anilino-1,2,3,4-tetrahydroquinolines.A single electron transfer mechanism was proposed to rationalize the products formation.
文摘The nucleophilic addition of Ti(IV) enolate derived from methyl aryl ketones to α, β–unsaturated compounds was found to be highly selective to give 1, 2 addition products.
基金We are grateful for the financial supports from the National Outstanding Youth Fund No.29925204)the Foundation for University Key Teacher by the Ministry of Education of Chinaa Visiting Fund of the National Laboratory of Applied Organic Chemistry.
文摘Regioselective addition reactions of silyl enolates to a, b-unsaturated aldehyde and its acetal catalyzed by MgI2 etherate give aldol adducts (1, 2-addition) preferentially over Michael adducts (1, 4-addition). This unique regioselectivity is distinctly different with other Lewis acidic promoters and may be attributed to the high oxyphilicity of IMg+.
文摘Substituent, temperature and solvent effects on tautomeric equilibria in several β-ketoamides have been investigated by means of nuclear magnetic resonance spectroscopy (NMR). Keto-enol equilibrium predominates over the amide-imidol one. The relative stability of the individual tautomers and the corresponding equilibrium shifts are explained considering electronic and steric effects and tautomer stabilization via internal hydrogen bonds. In solution, these compounds exist mainly as ketoamide and Z-enolamide tautomers, both presenting intramolecular hydrogen bonds.
文摘Purpose:Mild traumatic brain injury(TBI)is common but accurate diagnosis and its clinical consequences have been a problem.Maxillofacial trauma does have an association with TBI.Neuron-specific enolase(NSE)has been developed to evaluate neuronl damage.The objective of this study was to investigate the accuracy of NSE serum levels to detect mild brain injury of patients with sustained maxillofacial fractures during motor vehicle accidents.Methods:Blood samples were drawn from 40 healthy people(control group)and 48 trauma patients who has sustained isolated maxillofacial fractures and mild brain injury in motor vehicle accidents.Brain injuries were graded by Glasgow Coma Scale.In the trauma group,correlations between the NSE serum value and different facial fracture sites were also assessed.Results:The NSE serum level(mean±SD,ng/ml)in the 48 patients with maxillofacial fractures and mild TBI was 13.12±9.68,significantly higher than that measured in the healthy control group(7.72±1.82,p<0.001).The mean NSE serum level(ng/ml)in the lower part of the facial skeleton(15.44 with SD 15.34)was higher than that in the upper facial part(12.42 with SD 7.68);and the mean NSE level(ng/ml)in the middle-and lower part(11.97 with SD 5.63)was higher than in the middle part(7.88 with SD 2.64).Conclusion:An increase in NSE serum levels can be observed in patients sustained maxillofacial fractures and mild brain injury.
文摘Neuron-specific enolase (NSE) levels of cerebrospinal fluid (CSF) were measured in 39 patients with ischemic stroke and 15 controls. There was a significant increase of CSF NSE in acute ischemic stroke patients as compared with the controls. The altered CSF NSE levels correlated well with the infarct size in CT scan. The CSF NSE levels were higher in 6-multiinfarct dementia (MID) patients who were diagnosed after 6-month follow-up than those in 22 non-MID patients of this series. Our research supports the view that CSF NSE can be a useful biochemical marker for brain ischemia. The importance of CSF NSE in the study of dementia related to ischemic stroke is worth further studies.
基金Research Project of China Baoyuan Investment Co.,Ltd,Grant/Award Number:Program CBYI202102Haihe Laboratory of Cell Ecosystem Innovation Fund,Grant/Award Number:HH24KYZX0007+4 种基金CAMS Innovation Fund for Medical Sciences,Grant/Award Number:2021-I2M-1-024,2021-I2M-1-034 and 2023-I2M-2-001Fundamental Research Funds for the Central Universities,Grant/Award Number:3332022040 and 3332023164Open Research Project in State Key Laboratory of Vascular Homeostasis and Remodeling,Peking University,Grant/Award Number:202411State Key Laboratory Special Fund,Grant/Award Number:2060204the Non-profit Central Research Institute Fund of the Chinese Academy of Medical Sciences,Grant/Award Number:2023-PT180-01.
文摘Background:The Cre/loxP system is most popular in mice,but its application in rats has largely lagged far behind.The rat is vital laboratory animal,especially in toxicological and neurological studies.Generating genetic tools to manipulate neurons in rats could benefit neurological research.Methods:Using the CRISPR/Cas9 system,we inserted a Cre cassette into endogenous Thy1 and NeuN loci.Thy1-Cre rats featured a downstream P2A-linked insertion,while NeuN-Cre was inserted at the transcriptional start site.The Cre activity was assessed by crossing with a Cre reporter(Rosa26 imCherry)rat and through analyzing mCherry expression patterns.The specificity of cell type was further confirmed by immunofluorescence with NeuN antibody.Phenotypic consequences were assessed by crossing with ND1^(LSL) rats to deplete ND1,followed by monitoring weight/survival and conducting motor function tests.Results:We generated two neuron-specific rats(Thy1-Cre and NeuN-Cre),which exhibited high neuron-specific Cre expression in brain and spinal cord with minor leakage in other tissues.Thy1-Cre showed minor leakage in spleen,lung and kidney while NeuN-Cre showed minor leakage in spleen and kidney.ND1^(Thy1-Cre) and ND1^(NeuN-Cre) rats both showed decreased body weights and survival times.The ND1^(NeuN-Cre) rats died within two weeks,while ND1^(Thy1-Cre) rats lived longer with impaired motor function.Conclusions:We successfully generated two neuron-specific NeuN-Cre and Thy1-Cre rats,and systemically analyzed their expression pattern.
