Natural products,with their remarkable structural and biological diversity,have historically served as a vital bridge between chemistry,the life sciences,and medicine.They not only provide essential scaffolds for drug...Natural products,with their remarkable structural and biological diversity,have historically served as a vital bridge between chemistry,the life sciences,and medicine.They not only provide essential scaffolds for drug discovery but also inspire innovative strategies in drug development.The biomimetic synthesis of natural products employs principles from biomimicry,applying inspiration from biogenetic processes to design synthetic strategies that mimic biosynthetic processes.Biomimetic synthesis is a highly efficient approach in synthetic chemistry,as it addresses critical challenges in the synthesis of structurally complex natural products with significant biological and medicinal importance.It has gained widespread attention from researchers in chemistry,biology,pharmacy,and related fields,underscoring its interdisciplinary impact.In this perspective,we present recent advances and challenges in the biomimetic synthesis of natural products,along with the significance and prospects of this field,highlighting the transformative potential of biomimetic synthesis strategies for both chemical and biosynthetic approaches to natural product synthesis in the pursuit of novel therapeutic agents.展开更多
[2+2]-Type cyclobutane derivatives comprise a large family of natural products with diverse molecular architectures.However,the structure elucidation of the cyclobutane ring,including its connection mode and stereoche...[2+2]-Type cyclobutane derivatives comprise a large family of natural products with diverse molecular architectures.However,the structure elucidation of the cyclobutane ring,including its connection mode and stereochemistry,presents a significant challenge.Plumerubradins A-C(1-3),three novel iridoid glycoside[2+2]dimers featuring a highly functionalized cyclobutane core and multiple stereogenic centers,were isolated from the flowers of Plumeria rubra.Through biomimetic semisynthesis and chemical degradation of compounds 1-3,synthesis of phenylpropanoid-derived[2+2]dimers 7-10,combined with extensive spectroscopic analysis,single-crystal X-ray crystallography,and microcrystal electron diffraction experiments,the structures with absolute configurations of 1-3 were unequivocally elucidated.Furthermore,quantum mechanics-based^(1)H NMR iterative full spin analysis successfully established the correlations between the signal patterns of cyclobutane protons and the structural information of the cyclobutane ring in phenylpropanoid-derived[2+2]dimers,providing a diagnostic tool for the rapid structural elucidation of[2+2]-type cyclobutane derivatives.展开更多
AIM:To characterize the two components of theory of mind(ToM) in patients with esophageal cancer combined with depression.METHODS:Sixty-five patients with esophageal cancer combined with depression(depressed group) an...AIM:To characterize the two components of theory of mind(ToM) in patients with esophageal cancer combined with depression.METHODS:Sixty-five patients with esophageal cancer combined with depression(depressed group) and 62 normal controls(control group) were assessed using reading the mind in the eyes test,faux pas task,verbal fluency test,digit span test and WAIS IQ test.The depressed group was divided into two subgroups including psychotic depressed(PD) group(32 cases) and nonpsychotic depressed(NPD) group(33 cases).The clinical symptoms of patients were assessed using Beck depression inventory version Ⅱ and brief psychiatric reacting scale(BPRS).RESULTS:There was a significant difference between the depressed group and the control group on tasks involving ToM social perceptual components(mind reading:t = 7.39,P < 0.01) and tests involving ToM social cognitive components(faux pas questions:t = 13.75,P < 0.01),respectively.A significant difference was also found among the PD group,the NPD group and the control group on mind reading(F = 32.98,P < 0.01) and faux pas questions(χ 2 = 78.15,P < 0.01),respectively.The PD group and NPD group performed worse than normal group controls both on mind reading and faux pas questions(P < 0.05).The PD group performed significantly worse than the NPD group on tasks involving ToM(mind reading:F = 18.99,P < 0.01;faux pas questions:F = 36.01,P < 0.01).In the depressed group,there was a negative correlation between ToM performances and BPRS total score(mind reading:r =-0.35,P < 0.01;faux pas questions:r =-0.51,P < 0.01),and between ToM performances and hostile suspiciousness factor score(mind reading:r =-0.75,P < 0.01;faux pas questions:r =-0.73,P < 0.01),respectively.CONCLUSION:The two components of ToM are both impaired in patients with esophageal cancer combined with depression.This indicates that there may be an association between ToM deficits and psychotic symptoms in clinical depression.展开更多
BACKGROUND Swelling after apical microsurgery is a postoperative reaction and may reduce quality of life during healing.AIM To evaluate periapical swelling after apical microsurgery and determine potential risk factor...BACKGROUND Swelling after apical microsurgery is a postoperative reaction and may reduce quality of life during healing.AIM To evaluate periapical swelling after apical microsurgery and determine potential risk factors.METHODS Ninety-eight apical microsurgery patients were selected for this study.Before surgery,bone shadow volume and density of pathological tissue were measured by cone beam computed tomography.The other variables(age,gender,operative teeth number,fistula,preoperative swelling,drug use and preoperative root canal treatments)were assessed during examination.Swelling degree was confirmed by questionnaires for patients on postoperative days 1,7,14 and 21.Statistical analyses were performed to identify predictors for swelling.RESULTS Majority of patients reported moderate(45.9%)or severe(34.7%)swelling on day 1,and moderate(44.9%)or mild(45.9%)on postoperative day 7.Ninety-nine percent of patients had no or mild swelling on postoperative day 14.The average swelling level peaked on day 1 postoperatively and gradually decreased.Of statistical significance,age,bone shadow volume and density of pathological tissue acted as predictors of swelling(P<0.05).However,there was no significant difference in gender,tooth number,fistula,preoperative swelling,drug use,or preoperative root canal treatments(P>0.05).CONCLUSION Younger patients with larger shadow volume and density were significantly more likely to develop swelling after apical microsurgery.展开更多
Background：Some esophageal cancer patients complicated with depression exhibit cognitive impairments.Frontal electroencephalogram （EEG） may be used as a reliable biomarker for prefrontal-mediated cognitive function...Background：Some esophageal cancer patients complicated with depression exhibit cognitive impairments.Frontal electroencephalogram （EEG） may be used as a reliable biomarker for prefrontal-mediated cognitive functions.This study was to investigate alterations of EEG and frontal cognitive impairment in esophageal cancer patients complicated with depression and to assess their correlation.Methods：Sixty-five esophageal cancer patients with depression （study group） and 62 healthy controls （control group） were included in this study.The study group were assigned into psychotic depressed （PD,n =32） and nonpsychotic depressed （NPD,n =33） subgroups based on complication with psychotic symptoms （Brief Psychiatric Rating Scale [BPRS] 〉35）.EEG examination,Beck self-rating depression scale,and BPRS were used to assess clinical symptoms.Chi-square test,two independent sample t-test,one-way analysis of variance,and Kruskal-Wallis test were utilized to compare the variables between two groups.EEG abnormalities and scores of frontal cognitive function test were analyzed by partial correlation analysis in the PD and NPD subgroups.Results：Compared with control group,the study group displayed greater scores either in the Stroop test （19.89 ± 2.05 vs.24.12 ± 2.19,P =0.006） or Color Trails Test （CTT;11.92 ± 1.01 vs.15.02 ± 1.63,P =0.008）,and reduced score （35.05 ± 2.01 vs.32.11 ± 2.38,P =0.007） in the verbal fluency test （VFT）.Compared to NPD subgroup,PD subgroup exhibited increased scores in Stroop test （22.89 ± 2.07 vs.25.38 ± 2.32,P =0.009） and CTT （13.16 ± 1.71 vs.15.82 ± 1.13,P =0.008）.Moreover,increased scores in Stroop test and CTT as well as scores in VFT were associated with the severity of depression.The study group had an abnormal frontal EEG,such as α forward,α asymmetry,α moderation,and increased 0 activity relative to control group.Similarly,compared with NPD subgroup,PD subgroup displayed α forward,α asymmetry,and α moderation.The correlation test revealed that α forward and α asymmetry were negatively associated with VFT score,but positively correlated with the scores of CTT and the Stroop test in PD subgroup.In addition,α asymmetry in NPD subgroup was positively related to CTT scores.Conclusion：This study indicated that frontal cognitive impairment in esophageal cancer patients complicated with depression is associated with EEG alterations.展开更多
It is known that in supernova explosions, there might be a reverse shock wave in addition to the forward shock wave during the explosion phase, when the mass of supernova is in a certain range. In this paper, we propo...It is known that in supernova explosions, there might be a reverse shock wave in addition to the forward shock wave during the explosion phase, when the mass of supernova is in a certain range. In this paper, we propose to add the reverse shock wave to the previous supernova model, in which only the forward shock wave was included, and thus obtain a new model. By analyzing the resonance condition as well as the density jump in the new model and using the Landau-Zener method, an expression for the crossing probability in high density matter （PH） is given. We proceed to study how PH varies with time and with neutrino energy when both the reverse shock wave and the forward shock wave are considered. From comparison with the previous results, where only the effects of the forward shock wave were considered, it is clear that the reverse shock wave brings significant changes to PH.展开更多
基金financially supported by the National Key Research and Development Program of China(2023YFC3503902)the National Natural Science Foundation of China(82430108,82293681(82293680),and 82321004)+2 种基金the Guangdong Basic and Applied Basic Research Foundation(2022B1515120015 and 2024A1515030103)the Guangdong Major Project of Basic and Applied Basic Research(2023B0303000026)the Science and Technology Projects in Guangzhou(202102070001)。
文摘Natural products,with their remarkable structural and biological diversity,have historically served as a vital bridge between chemistry,the life sciences,and medicine.They not only provide essential scaffolds for drug discovery but also inspire innovative strategies in drug development.The biomimetic synthesis of natural products employs principles from biomimicry,applying inspiration from biogenetic processes to design synthetic strategies that mimic biosynthetic processes.Biomimetic synthesis is a highly efficient approach in synthetic chemistry,as it addresses critical challenges in the synthesis of structurally complex natural products with significant biological and medicinal importance.It has gained widespread attention from researchers in chemistry,biology,pharmacy,and related fields,underscoring its interdisciplinary impact.In this perspective,we present recent advances and challenges in the biomimetic synthesis of natural products,along with the significance and prospects of this field,highlighting the transformative potential of biomimetic synthesis strategies for both chemical and biosynthetic approaches to natural product synthesis in the pursuit of novel therapeutic agents.
基金supported by the National Key R&D Program of China(No.2023YFC3503902)the National Natural Science Foundation of China(Nos.82293681(82293680)and 82321004)+2 种基金the Guangdong Basic and Applied Basic Research Foundation(Nos.2022B1515120015 and 2021A1515111021)the Guangdong Major Project of Basic and Applied Basic Research(No.2023B0303000026)the Science and Technology Projects in Guangzhou(No.202102070001).
文摘[2+2]-Type cyclobutane derivatives comprise a large family of natural products with diverse molecular architectures.However,the structure elucidation of the cyclobutane ring,including its connection mode and stereochemistry,presents a significant challenge.Plumerubradins A-C(1-3),three novel iridoid glycoside[2+2]dimers featuring a highly functionalized cyclobutane core and multiple stereogenic centers,were isolated from the flowers of Plumeria rubra.Through biomimetic semisynthesis and chemical degradation of compounds 1-3,synthesis of phenylpropanoid-derived[2+2]dimers 7-10,combined with extensive spectroscopic analysis,single-crystal X-ray crystallography,and microcrystal electron diffraction experiments,the structures with absolute configurations of 1-3 were unequivocally elucidated.Furthermore,quantum mechanics-based^(1)H NMR iterative full spin analysis successfully established the correlations between the signal patterns of cyclobutane protons and the structural information of the cyclobutane ring in phenylpropanoid-derived[2+2]dimers,providing a diagnostic tool for the rapid structural elucidation of[2+2]-type cyclobutane derivatives.
基金Supported by Leading Scientific Research Project of the Health Department of Jiangsu Province,China,No.Z201220Major Project of the Health Department of Changzhou,China,No.ZD201105Changzhou Sci-Tech Support Project for Social Development,No.CE20125021
文摘AIM: To investigate the short-term efficacy and tolerability of radiotherapy plus thalidomide in patients with esophageal cancer (EC).
文摘AIM:To characterize the two components of theory of mind(ToM) in patients with esophageal cancer combined with depression.METHODS:Sixty-five patients with esophageal cancer combined with depression(depressed group) and 62 normal controls(control group) were assessed using reading the mind in the eyes test,faux pas task,verbal fluency test,digit span test and WAIS IQ test.The depressed group was divided into two subgroups including psychotic depressed(PD) group(32 cases) and nonpsychotic depressed(NPD) group(33 cases).The clinical symptoms of patients were assessed using Beck depression inventory version Ⅱ and brief psychiatric reacting scale(BPRS).RESULTS:There was a significant difference between the depressed group and the control group on tasks involving ToM social perceptual components(mind reading:t = 7.39,P < 0.01) and tests involving ToM social cognitive components(faux pas questions:t = 13.75,P < 0.01),respectively.A significant difference was also found among the PD group,the NPD group and the control group on mind reading(F = 32.98,P < 0.01) and faux pas questions(χ 2 = 78.15,P < 0.01),respectively.The PD group and NPD group performed worse than normal group controls both on mind reading and faux pas questions(P < 0.05).The PD group performed significantly worse than the NPD group on tasks involving ToM(mind reading:F = 18.99,P < 0.01;faux pas questions:F = 36.01,P < 0.01).In the depressed group,there was a negative correlation between ToM performances and BPRS total score(mind reading:r =-0.35,P < 0.01;faux pas questions:r =-0.51,P < 0.01),and between ToM performances and hostile suspiciousness factor score(mind reading:r =-0.75,P < 0.01;faux pas questions:r =-0.73,P < 0.01),respectively.CONCLUSION:The two components of ToM are both impaired in patients with esophageal cancer combined with depression.This indicates that there may be an association between ToM deficits and psychotic symptoms in clinical depression.
基金Supported by Natural Science Foundation of Zhejiang Province,China,No. LQ21H270001
文摘BACKGROUND Swelling after apical microsurgery is a postoperative reaction and may reduce quality of life during healing.AIM To evaluate periapical swelling after apical microsurgery and determine potential risk factors.METHODS Ninety-eight apical microsurgery patients were selected for this study.Before surgery,bone shadow volume and density of pathological tissue were measured by cone beam computed tomography.The other variables(age,gender,operative teeth number,fistula,preoperative swelling,drug use and preoperative root canal treatments)were assessed during examination.Swelling degree was confirmed by questionnaires for patients on postoperative days 1,7,14 and 21.Statistical analyses were performed to identify predictors for swelling.RESULTS Majority of patients reported moderate(45.9%)or severe(34.7%)swelling on day 1,and moderate(44.9%)or mild(45.9%)on postoperative day 7.Ninety-nine percent of patients had no or mild swelling on postoperative day 14.The average swelling level peaked on day 1 postoperatively and gradually decreased.Of statistical significance,age,bone shadow volume and density of pathological tissue acted as predictors of swelling(P<0.05).However,there was no significant difference in gender,tooth number,fistula,preoperative swelling,drug use,or preoperative root canal treatments(P>0.05).CONCLUSION Younger patients with larger shadow volume and density were significantly more likely to develop swelling after apical microsurgery.
文摘Background：Some esophageal cancer patients complicated with depression exhibit cognitive impairments.Frontal electroencephalogram （EEG） may be used as a reliable biomarker for prefrontal-mediated cognitive functions.This study was to investigate alterations of EEG and frontal cognitive impairment in esophageal cancer patients complicated with depression and to assess their correlation.Methods：Sixty-five esophageal cancer patients with depression （study group） and 62 healthy controls （control group） were included in this study.The study group were assigned into psychotic depressed （PD,n =32） and nonpsychotic depressed （NPD,n =33） subgroups based on complication with psychotic symptoms （Brief Psychiatric Rating Scale [BPRS] 〉35）.EEG examination,Beck self-rating depression scale,and BPRS were used to assess clinical symptoms.Chi-square test,two independent sample t-test,one-way analysis of variance,and Kruskal-Wallis test were utilized to compare the variables between two groups.EEG abnormalities and scores of frontal cognitive function test were analyzed by partial correlation analysis in the PD and NPD subgroups.Results：Compared with control group,the study group displayed greater scores either in the Stroop test （19.89 ± 2.05 vs.24.12 ± 2.19,P =0.006） or Color Trails Test （CTT;11.92 ± 1.01 vs.15.02 ± 1.63,P =0.008）,and reduced score （35.05 ± 2.01 vs.32.11 ± 2.38,P =0.007） in the verbal fluency test （VFT）.Compared to NPD subgroup,PD subgroup exhibited increased scores in Stroop test （22.89 ± 2.07 vs.25.38 ± 2.32,P =0.009） and CTT （13.16 ± 1.71 vs.15.82 ± 1.13,P =0.008）.Moreover,increased scores in Stroop test and CTT as well as scores in VFT were associated with the severity of depression.The study group had an abnormal frontal EEG,such as α forward,α asymmetry,α moderation,and increased 0 activity relative to control group.Similarly,compared with NPD subgroup,PD subgroup displayed α forward,α asymmetry,and α moderation.The correlation test revealed that α forward and α asymmetry were negatively associated with VFT score,but positively correlated with the scores of CTT and the Stroop test in PD subgroup.In addition,α asymmetry in NPD subgroup was positively related to CTT scores.Conclusion：This study indicated that frontal cognitive impairment in esophageal cancer patients complicated with depression is associated with EEG alterations.
基金Supported by National Natural Science Foundation of China(11605150)Natural Science Foundation of Shandong Province(ZR2016AQ02)
文摘It is known that in supernova explosions, there might be a reverse shock wave in addition to the forward shock wave during the explosion phase, when the mass of supernova is in a certain range. In this paper, we propose to add the reverse shock wave to the previous supernova model, in which only the forward shock wave was included, and thus obtain a new model. By analyzing the resonance condition as well as the density jump in the new model and using the Landau-Zener method, an expression for the crossing probability in high density matter （PH） is given. We proceed to study how PH varies with time and with neutrino energy when both the reverse shock wave and the forward shock wave are considered. From comparison with the previous results, where only the effects of the forward shock wave were considered, it is clear that the reverse shock wave brings significant changes to PH.
