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Acute and Sub-chronic Toxicity of Indole Alkaloids Extract from Leaves of Alstonia scholaris (L.) R. Br. in Beagle Dogs

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Natural Products and Bioprospecting 2020年第4期10卷 209-220页

作者： Yun-Li Zhao Min Su jian-hua shang Xia Wang Guang-Lei Bao Jia Ma Qing-Di Sun Fang Yuan Jing-Kun Wang Xiao-Dong Luo State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China Yunnan Institute of Medical Material Kunming 650111People’s Republic of China Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of Education and Yunnan ProvinceSchool of Chemical Science and TechnologyYunnan UniversityKunming 650091People’s Republic of China jiangsu Nhwa Pharmaceutical Co. LtdXuzhou 221009People’s Republic of China

Alstonia scholaris(L.)***.,an evergreen tropical plant rich in indole alkaloids with significant physiological activity,is traditionally used to treat respiratory diseases in *** study was conducted to establish the toxicity profile of the alkaloid extract(TA)of *** leaves in *** oral administration of a single dose(4 g/***),a num-ber of transient symptoms,such as unsteady gait,drooling,emesis,and reddening of peri-oral mucosa,were observed,but no treatment-related mortality.A sub-chronic toxicity study with a range of doses of TA(20,60 and 120 mg/***)was conducted for a 13-week treatment period,followed by 4-week recovery *** for emesis and drooling in majority of animals in 120 mg/*** treatment group,no clinical changes were observed in TA-treated *** from electrocardiography,bone marrow,urine,fecal,hematology and clinical chemistry analyses were comparable between TA-treated and control *** significant differences in the relative organ weights and histopathological characteristics were evident between the TA-treated and control ***,the non-observed-adverse-effect-level(NOAEL)of TA was established as 120 mg/*** results add further knowledge to the safety database for indole alkaloid extracts from *** with potential utility as novel drug candidates.

关键词： Alstonia scholaris Indole alkaloids Acute toxicity Sub-chronic toxicity Beagle dog Non-observed-adverse-effect-level

Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations: A Review

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Structural Durability & Health Monitoring 2025年第1期19卷 25-54页

作者： Chao Zhang shang-Xi Lai hua-Ping Wang School of Civil Engineering and Mechanics Lanzhou UniversityLanzhou730000China Key Laboratory of Special Functional Materials and Structural Design Ministry of EducationLanzhou UniversityLanzhou730000China

Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the ***,it is particularly signiﬁcant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientiﬁc basis for structural damage identiﬁcation and dynamic model modiﬁ*** view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and brieﬂy describes how to identify structural damages based on the derived modal *** paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),brieﬂy describes damage identiﬁcation methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artiﬁcial intelligence(AI)methods in the direction of modal parameter recognition and damage identiﬁcation is further *** on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identiﬁcation methods are given to provide scientiﬁc references for the optimized design and functional upgrading of SHM systems.

关键词： Structural health monitoring data information modal parameters damage identiﬁcation AI method

Genotoxicity and Safety Pharmacology Studies of Indole Alkaloids Extract from Leaves of Alstonia scholaris (L.) R. Br.

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Natural Products and Bioprospecting 2020年第3期10卷 119-129页

Indole alkaloids extract(IAAS)was prepared from leaves of Alstonia scholaris(L.)***.,an evergreen tropical plant widely distributed throughout the *** plant has been used historically by the Dai ethnic people of China to treat respiratory *** study evaluated the genotoxicity and safety pharmacology of IAAS to support clinical *** bacterial reverse mutation(Ames)test,in vitro mammalian chromosomal aberration test,and in vivo mammalian erythrocyte micronucleus(MN)test were performed to evaluate *** were administered IAAS(240,480,or 960 mg/kg bw)once orally to observe adverse central nervous system ***,beagle dogs were administered IAAS(10,30,60 mg/kg bw)once via the duodenum to evaluate its effects on the cardiovascular and respiratory *** with or without S9-induced metabolic activation showed no genotoxicity in the Ames test up to 500μg/plate,in the mammalian chromosomal aberration test up to 710μg/mL,or in the MN test up to 800 mg/kg *** abnormal neurobehavioral effects were observed in mice following treatment with up to 960 mg/kg bw of ***,blood pressure,heart rate,electrocardiogram parameters,and depth and rate of breathing in anesthetized beagle dogs did not differ among the IAAS doses or from the vehicle *** data indicated that IAAS did not induce mutagenicity,clastogenicity,or genotoxicity,and no pharmaco-toxicological effects were observed in the respiratory,cardiovascular,or central nervous *** results increased understanding of safety considerations associated with IAAS,and may indicate that IAAS is a possible drug candidate.

关键词： Alstonia scholaris Indole alkaloids extract Genotoxicity Safety pharmacology Mice Dogs

Acute and Chronic Toxicity of Indole Alkaloids from Leaves of Alstonia scholaris (L.) R. Br. in Mice and Rats

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Natural Products and Bioprospecting 2020年第2期10卷 77-88页

作者： Yun-Li Zhao Min Su jian-hua shang Xia Wang Guy Sedar Singor Njateng Guang-Lei Bao Jia Ma Qing-Di Sun Fang Yuan Jing-Kun Wang Xiao-Dong Luo State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China Yunnan Institute of Medical Material Kunming 650111People’s Republic of China Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of Education and Yunnan ProvinceSchool of Chemical Science and TechnologyYunnan UniversityKunming 650091People’s Republic of China Laboratory of Microbiology and Antimicrobial Substances Faculty of ScienceUniversity of DschangP.O.Box 67DschangCameroon jiangsu Nhwa Pharmaceutical Co. LtdXuzhou 221009People’s Republic of China

Alstonia scholaris(L.)***.(Apocynaceae)is an evergreen tree that has been used to treat lung *** this study,the toxicity profile of indole alkaloids from leaves of *** was *** acute toxicity tests,mice were adminis-tered total alkaloids(TA)and five indole *** a chronic toxicity test,rats were continuously administered TA(50,100,and 300 mg/kg bw)for 13 weeks,followed by a 4-week recovery.A single administration of TA affected the behavior of mice,and at 12.8 g/kg bw,prone position,shortness of breath,wheezing,and convulsion were *** half-lethal dose(LD50)in mice was 5.48 g/kg bw,almost 2740 times the clinical dose in *** the five indole alkaloids,the maximum tolerance dose in mice ranged from 0.75 to 4 g/kg *** TA-treated rats did not die and showed no adverse effects or dose-dependent changes in weight or food and water consumption,despite fluctuations in hematological and bio-chemical parameters compared with historical ***,both gross and histopathological observations revealed no abnormalities in any *** daily oral administration to rats,the non-observed-adverse-effect-level of TA was 100 mg/kg *** results indicate that TA is safe for clinical use.

关键词： Alstonia scholaris Indole alkaloids Acute toxicity Chronic toxicity Non-observed-adverse-effect-level

Stepwise assembly to construct stable copper(I) cluster-based circularly polarized luminescent MOFs

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Science China Chemistry 2025年

作者： Jing-Wen Xie Meng-Ting Wang Yan Jin Si Li jian-hua Qin Shuang-Quan Zang Tomas C.W.Mak College of Chemistry Henan Key Laboratory of Crystalline Molecular Functional Materials Zhengzhou University College of Chemistry and Chemical Engineering Luoyang Normal University Department of Chemistry The Chinese University of Hong Kong

Circularly polarized luminescence （CPL） materials have been extensively studied in recent years owing to their widespread applications in 3D display,optical storage,optical anti-counterfeiting,and biological imaging,***（I） clusters have emerged as a promising candidate for CPL materials,driven by their cost-effectiveness,superior luminescent properties,precise structure,and low ***,the poor environmental stability of copper（I） clusters renders their synthesis and preservation challenging,thereby significantly impeding their ***,we have designed and synthesised a chiral double-coordinated ligand in order to construct copper（I） cluster nodes that can be further *** anticipated,by utilizing stepwise assembly strategy,a Cu4cluster node co-modified by chiral alkynyl ligands and triphenylphosphine was further assembled with Cd2+ions to obtain 2D layers structure,L/*** L/D-Cu4-Cd exhibits excellent stability and optical properties,including bright yellow emission,solvent-responsive luminescence,and CPL activity with a maximum glumup to 2.0×10-3,which shows potential applications in the WLED and *** interestingly,the material also exhibits deflection ability towards different wavelengths of linearly polarized light,showing certain potential in the preparation of circular polarizer.

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Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke

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Neural Regeneration Research 2025年第3期20卷 845-857页

作者： Lin-Yan huang Yi-De Zhang Jie Chen Hai-Di Fan Wan Wang Bin Wang Ju-Yun Ma Peng-Peng Li Hai-Wei Pu Xin-Yian Guo jian-Gang Shen Su-hua Qi School of Medical Technology Xuzhou Key Laboratory of Laboratory DiagnosticsXuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Pharmacy Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Department of Laboratory Medicine Branch Hospital of Huai’an First People’s HospitalHuai’anJiangsu ProvinceChina Department of Laboratory Medicine the Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Chinese Medicine The University of Hong KongHong Kong Special Administrative RegionChina

It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late ***,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain *** previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently *** simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic *** found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous ***,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid *** results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/***,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and *** suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion *** levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-*** transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear ***,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

关键词： cell differentiation cerebral ischemia/reperfusion injury chlorination hypochlorous acid microglia neural stem cell neurogenesis nuclear translocation stroke β-catenin

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Clinicopathological differences between patients with schistosomal appendicitis and non schistosomal appendicitis:A retrospectively study of past ten years

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World Journal of Clinical Cases 2025年第2期13卷 24-32页

作者： Xiao-Yi Wang Yao Hao Zi-jian Wang Xiu-Liang Xu jiang-hua Yang Department of Infectious Diseases The First Affiliated of Wannan Medical CollegeWuhu 241001Anhui ProvinceChina

BACKGROUND Chronic schistosomiasis causes multiple organ and multiple system diseases,especially the digestive *** eggs are mainly deposited in the stomach,liver and colorectal,but a few eggs are deposited in the appendix and cause *** present,there are few studies on schistosomal *** To explore the differences in epidemiological,clinical and pathological characteristics between schistosomal appendicitis and non-schistosomal appendicitis over the past decade in order to assess the impact of schistosomiasis on *** The differences of general data,clinical data and laboratory examination data of patients with appendicitis from October 2013 to October 2023 were retrospectively *** patients were divided into two groups for *** were 136 patients in schistosomal appendicitis group and 5418 patients in non-schistosomal appendicitis *** Schistosomal appendicitis accounted for 2.45%of all patients with appendicitis,and the annual proportion in the past decade was 2.2%,2.9%,1.8%,1.9%,3.4%,3.1%,1.9%,1.6%,3%,2.6%,*** prevalence of schistosomal appendicitis was middle-aged and elderly males,with an average age of 61.73±15.335 *** main population of non-schistosomal appendicitis was middle-aged men,with an average age of 35.8±24.013 years(P<0.001).The distribution of pathological types of appendicitis was different between the two groups(P<0.001).The incidence of acute suppurative appendicitis in non-schistosomal appendicitis was higher than that in schistosomal appendicitis[odds ratio(OR)=0.504;95%confidence interval(CI):0.349-0.728;P<0.001].The proportion of acute attack of chronic appendicitis in schistosomal appendicitis was higher than that in non-schistosomal appendicitis(OR=2.614;95%CI:1.815-3.763;P<0.001).The proportion of schistosomal appendicitis patients complicated with colorectal cancer was higher than that of nonschistosomal appendicitis patients(OR=5.087;95%CI:1.427-

关键词： Schistosomal appendicitis Schistosomiasis Appendix Colorectal cancer Clinicopathological characteristics

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虚拟装配中的零部件物理属性建模与仿真技术

系统仿真学报 2008年第S1期20卷 81-83,87页

作者：侯伟伟刘检华尚炜张志贤刘伟东北京理工大学机械与车辆工程学院北京100081

虚拟装配的拟实性是影响该技术能否得到广泛应用的主要因素之一。基于物理属性的虚拟装配技术通过对物体的物理属性进行仿真和模拟,使得虚拟环境中的装配过程更接近于实际的装配过程。方法首先对基于物理属性的计算机仿真技术国内外研... 详细信息

虚拟装配的拟实性是影响该技术能否得到广泛应用的主要因素之一。基于物理属性的虚拟装配技术通过对物体的物理属性进行仿真和模拟,使得虚拟环境中的装配过程更接近于实际的装配过程。方法首先对基于物理属性的计算机仿真技术国内外研究现状进行了综述,在此基础上提出了基于物理属性的虚拟装配过程研究模型,给出了虚拟环境下零部件物理属性建模方法,并对虚拟环境中基于物理属性的装配过程仿真技术进行了阐速,最后结合实例对相关技术进行了初步验证。

关键词：物理属性建模虚拟装配虚拟现实装配过程仿真

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Emplacement age and tectonic implications of the brecciated limestone at the edge of the Longmenshan klippe

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Science China Earth Sciences 2016年第3期59卷 590-600页

作者： XUE Zhen hua shang Qing hua jianG Wen Ying WANG Qing Chen LI Shuang jian State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Betljing 100029 Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China University of Chinese Academy of Sciences Beijing 100049 China Institute of Petroleum Exploration and Development China Petroleum and Chemical Corporation Beijing 100083 China

The Longmenshan thrust belt(LMTB) is one of the best natural laboratories for thin-skinned tectonics and has developed a series of NE-SW trending fold-and-thrust structures represented by a series of nappes and klippes, exemplified by the Tangbazi and Bailuding klippe. However, the timing and emplacement mechanism of these klippes are still in dispute. Three possible mechanisms have been proposed:(1) a Mesozoic-Cenozoic southeastward thrusting,(2) a Cenozoic gravity gliding, and(3) glacial deposition. Almost all of these klippes are tectonic and overlaid on folded Late Triassic sandstone except the Tangbazi klippe, which is located in the center of the LMTB and has a narrow tail extending southeastward and covering Jurassic-Quaternary rocks. This geometric relationship is considered the most important stratigraphic evidence to support the post-Cenozoic emplacement of the Longmenshan klippe. Our structural and petrological observations show that the rocks at the front of the Tangbazi and Bailuding structures are brecciated limestone, which is assumed to have been generated by a gravitational collapse and is not characteristic of the massive Permian strata. Artemisia pollen, which has been exclusively recognized in post-Late Eocene strata in Central Asia, was found in the matrix of this brecciated limestone. Therefore, our discovery indicates that the brecciated limestone was deposited after the Late Eocene rather than during the Permian as annotated on the geological map. In contrast, unbrecciated, massive Permian limestone overlaid on the folded Late Triassic rocks. Hence, the anomalous relationship of Permian strata overlaying Late Triassic rocks cannot be evidence of Cenozoic emplacement. According to currently recognized bulk strata relationships, we can only be sure that the klippe was emplaced in the post Late Triassic. The petrological characteristics of the brecciated limestone show that it was crumbled before the re-sedimentation of the breccia, implying tha

关键词： Longmenshan thrust belt Klippe Artemisia Brecciated limestone Thin-skinned structure

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