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Cytotoxic and antibacterial polyketide-indole hybrids synthesized from indole-3-carbinol by Daldinia eschscholzii

Acta Pharmaceutica Sinica B 2019年第2期9卷 369-380页

作者： Liping Lin Nan Jiang Huimin Wu Yaning mei Jie Yang Renxiang Tan State Key Laboratory Cultivation Base for TCM Quality and Efficacy Nanjing University of Chinese Medicine State Key Laboratory of Pharmaceutical Biotechnology Nanjing University School of Pharmacy Nanjing Medical University Department of Clinical Laboratory the First Affiliated Hospital of Nanjing Medical University Jiangsu Province Academy of Traditional Chinese Medicine

Two skeletally undescribed polyketide-indole hybrids(PIHs), named indolchromins A and B,were generated from indole-3-carbinol(I3 C) in the fungal culture(Daldinia eschscholzii). The indolchromin structures were elucidated mainly by their 1 D and 2 D NMR spectra with the former confirmed by the single-crystal X-ray crystallographic analysis. Each indolchromin alkaloid was chirally separated into four isomers, whose absolute configurations were assigned by comparing the recorded circular dichroism(CD) spectra with the electronic CD(ECD) curves computed for all optional stereoisomers. Furthermore, the indolchromin construction pathways in fungal culture were clarified through enzyme inhibition, precursor feeding experiment, and energy calculation. The cascade reactions,including decarboxylative Claisen condensation catalyzed by 8-amino-7-oxononanoate synthase(AONS),C(sp3)-H activation, double bond migration, and Michael addition, all undergone compatibly during the fungal cultivation. In an MIC range of 1.3–8.6 μmol/L,(2 S,4 R)-and(2 R,4 S)-indolchromin A and(2 R,4 S)-indolchromin B are inhibitory against Clostridium perfringens, Clostridium difficile, Veillonella sp.,Bacteroides fragilis, and Streptococcus pyogenes.(2 R,4 S)-Indolchromin A and(2 S,4 S)-indolchromin B were cytotoxic against the human breast cancer cell line MDA-MB-231 with IC50 values of 27.9 and131.2 nmol/L, respectively, with the former additionally active against another human breast cancer cell line MCF-7(IC_(50)94.4 nmol/L).

关键词： Polyketide-indole hybrids Indole-3-carbinol Daldinia eschscholzii 8-Amino-7-oxononanoate synthase Decarboxylative Claisen condensation Antibacterial Anticancer

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Critical respiratory failure due to pregnancy complicated by COVID-19 and bacterial coinfection:A case report

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World Journal of Clinical Cases 2023年第23期11卷 5559-5566页

作者： Shuang Zhou mei-Hong Liu Xiao-Peng Deng Department of Pulmonary and Critical Care Medicine First Affiliated Hospital of Dalian Medical UniversityDalian 116011Liaoning ProvinceChina Department of Gynaecology and Obstetrics Dalian Women and Children’s Medical GroupDalian 116011Liaoning ProvinceChina

BACKGROUND In the past 3 years,the global pandemic of coronavirus disease 2019(COVID-19)has posed a great threat to human life and *** the causes of death in COVID-19 patients,combined or secondary bacterial infection is an important *** a special group,pregnant women experience varying degrees of change in their immune status,cardiopulmonary function,and anatomical structure during pregnancy,which puts them at higher risk of contracting ***-19 infection during pregnancy is associated with increased adverse events such as hospitalisation,admission to the intensive care unit,and mechanical ***,pregnancy combined with coinfection of COVID-19 and bacteria often leads to critical respiratory failure,posing severe challenges in the diagnosis and treatment *** SUMMARY We report a case of COVID-19 complicated with Staphylococcus aureus(***)coinfection in a pre-gnant woman at 34 wk of *** rapid progression of pulmonary lesions caused severe respiratory failure,and she received noninvasive ventilator-assisted respiratory ***,we delivered a foetus via emergency caesarean section after accelerating the maturity of the foetal pulmonary system,and the respiratory condition of the puerperant woman significantly improved after the delivery of the *** fluid was taken under tracheoscopy to quickly search for pathogens by the metagenomic nextgeneration sequencing(mNGS),and both COVID-19 and *** were *** targeted anti-infective treatment,the maternal condition gradually improved,and the patient was discharged from the *** The coinfection of pregnancy with COVID-19 and bacteria often leads to critical respiratory failure,which is a great challenge in the process of diagnosis and *** is crucial to choose the right time to deliver the foetus and to quickly find pathogens by mNGS.

关键词： Pregnancy Coronavirus disease 2019 Combined with staphylococcus aureus Metagenomic next-generation sequencing Critical respiratory failure Case report

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Hydrothermal Synthesis and Crystal Structure of a Cadmium(II) Polymer with One-dimensional Chain Structure: [Cd(bpy)(BDC)]_n·nbpy

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Chinese Journal of Structural Chemistry 2007年第5期26卷 537-540页

作者： LI Xiu-mei NIU Yan-Ling WANG Qing-Wei CUI Yun-Cheng LIUBo Department of Chemistry Tonghua Teachers College Tonghua Jilin 134002 China Jilin Normal University Siping Jilin 136000 China

A metal-organic coordination polymer [Cd（bpy）（BDC）]n·nbpy （bpy = 2,2-bipyri-dine, H2BDC = terephthalic acid） has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group C2/c with a = 15.723（5）, b = 21.695（5）, c = 7.576（5） A, β = 116.171（7）°, V = 2319.3（18）A^3, C28H20CdN4O4, Mr = 588.88, Dc = 1.686 g/cm^3, μ（MoKα） = 0.987 mm^-1, F（000） = 1184, Z = 4, the final R = 0.0464 and wR = 0.0831 for 1882 observed reflections （Ⅰ〉 2σ（Ⅰ））. It exhibits a three-dimensional network with channels constructed from one-dimensional coordination chains via C–H…O hydrogen bonds and significant aromatic π-π stacking interactions.

关键词： hydrothermal synthesis crystal structure coordination polymer

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The Susceptibilities of Oxya chinensis(Orthoptera:Acridoidea) to Malathion and Comparison of the Esterase Properties from Three Collected Populations in Tianjin Area,China

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Agricultural Sciences in China 2009年第1期8卷 76-82页

作者： WU Hai-hua YANG mei-ling GUO Ya-ping MA En-bo Institute of Applied Biology Shanxi University Taiyuan 030006 P.R.China

The susceptibilities of Oxya chinensis to malathion were studied in three populations collected from outskirt of Tianjin, China, using bioassays and biochemical analysis. Populations were chosen to represent different exposure to insecticides： BDG （Beidagang; low exposure）, BD （Baodi; high exposure previously but low exposure now）, and JN （Jinnan; high exposure）. The results showed that the LD50 values of BD and JN populations were 3.95- and 12.02-fold and 3.64- and 10.07- fold higher than that of BDG population in females and males, respectively. The LD50 values in females were higher than those in males. The results of biochemical analysis indicated that the esterase （EST） activities in JN population were higher than those in BD and BDG populations. They showed that when α-NA, α-NB, and α-NA were used as substrates, females＇ EST activities of JN population were 1.11-, 1.30-, and 1.14-fold and 1.39-, 1.59-, and 1.54-fold higher than those of BD and BDG populations, respectively. When α-NA, α-NB, and β-NA were used as substrates, males＇ EST activities of JN population were 1.13-, 1.12-, and 1,00-fold and 1.20-, 1.14-, and 1.07-fold higher than those of BD and BDG populations, respectively. The results also showed that the specific activities of the females were higher than those of the males in the BD and JN populations, whereas the specific activities of the males were higher than those of the females in the BDG population. The results of bioassay were consistent with those of biochemical analysis. Thus, it was inferred that the elevated ESTs activities might play an important role in conferring the differences of susceptibility of O. chinensis to malathion in the three collected populations. Enzyme kinetic studies indicated that the Km and Vmax values were different among the three collected populations and between the females and the males. The observed changes in the kinetic parameters might be explained by differential expression patterns of isozymes so that th

关键词： Oxya chinensis esterase enzyme kinetics malathion susceptibility

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Visible-light-mediated external-reductant-free reductive cross coupling of benzylammonium salts with(hetero)aryl nitriles

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Science China Chemistry 2019年第11期62卷 1519-1524页

作者： Meng Miao Li-Li Liao Guang-mei Cao Wen-Jun Zhou Da-Gang Yu Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China College of Chemistry and Chemical Engineering Neijiang Normal UniversityNeijiang 641100China

Herein we report a novel visible-light-mediated external reductant-free reductive cross coupling for the construction of C sp2–C sp3 bonds.A variety of benzylammonium salts underwent selective coupling with(hetero)aryl nitriles to deliver important diarylmethanes under mild reaction ***,photocatalysts can be omitted for many cases,which might involve the electron donor acceptor(EDA)*** studies indicated benzylic radicals might be involved as the key ***,the in situ generated NMe3 via cleavage of C–N bond in ammonium salts acts as the electron donor,thus avoiding the use of external-reductant.

关键词： reductive cross coupling visible light external-reductant-free

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Prompt Electrodeposition of Ni Nanodots on Ni Foam to Construct a High-Performance Water-Splitting Electrode:Efficient, Scalable,and Recyclable

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Nano-Micro Letters 2019年第3期11卷 79-91页

作者： Hongtao Yu Ting Quan Shilin mei Zdravko Kochovski Wei Huang Hong Meng Yan Lu Soft Matter and Functional Materials Helmholtz-Zentrum Berlin für Materialien und EnergieHahn.Meitner Platz114109BerlinGermany Key Lab for Flexible Electronics&Institute of Advanced Materials Jiangsu National Synergistic InnovationCenter for Advanced Materials(SICAM)Nanjing Tech University30South Puzhu RoadNanjingPeople’s Republic of China Institute of Chemistry University of Potsdam14467PotsdamGermany

In past decades,Ni-based catalytic materials and electrodes have been intensively explored as low-cost hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)catalysts for water *** increasing demands for Ni worldwide,simplifying the fabrication process,increasing Ni recycling,and reducing waste are tangible sustainability ***,binder-free,heteroatom-free,and recyclable Ni-based bifunctional catalytic electrodes were fabricated via a one-step quick electrodeposition ***,active Ni nanodot(NiND)clusters are electrodeposited on Ni foam(NF)in Ni(NO3)2 acetonitrile *** drying in air,NiO/NiND composites are obtained,leading to a binder-free and heteroatom-free NiO/NiNDs@NF catalytic *** electrode shows high efficiency and long-term stability for catalyzing hydrogen and oxygen evolution reactions at low overpotentials(10ηHER= 119 mV and 50ηOER=360 mV)and can promote water catalysis at 1.70 V@ 10mA *** importantly,the recovery of raw materials(NF and Ni(NO3)2)is quite easy because of the solubility of NiO/NiNDs composites in acid solution for recycling the ***,a large-sized(S^70 cm2)NiO/NiNDs@NF catalytic electrode with high durability has also been *** method provides a simple and fast technology to construct high-performance,low-cost,and environmentally friendly Ni-based bifunctional electrocatalytic electrodes for water splitting.

关键词： Electrodeposition Ni nanodots Bifunctional catalysts Water splitting Large-size

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Influence of physical self and mindfulness on the academic possible selves of freshman nursing students

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Frontiers of Nursing 2019年第3期6卷 241-248页

作者： mei-Ling Han Hai-Ying Qu School of Humanities and Social Sciences Binzhou Medical University Yantai

Objective:The purposes of this study were to investigate the general level of the mindfulness,physical self,and academic possible selves in the freshman nursing students,and to explore the relationship among the three variables,so as to provide a theoretical basis for the freshmen to improve their academic achievement on the basis of the correct understanding of the physical ***:A total of 360 freshman nursing students were enrolled in this study from a medical school in Yantai *** were collected using three questionnaires:Body Self-description Questionnaire,Five Factors Mindfulness Questionnaire,and Academic Possible Selves *** were 341 valid ***:The mindfulness of the freshmen nursing students was at a medium level(3.03±0.28),their attitude to physical self(3.66±0.58)and academic possible selves(3.33±0.50)were *** were significant gender differences among coordination,physical activity,athletic ability,strength,endurance,observation,non-response,total physical self-score,and negative future academic possible *** the above factors,except negative future academic possible selves,the scores for boys were higher than that for girls(all P<0.05).There were significant positive relationships between physical self,mindfulness,and academic possible ***-esteem,acting with awareness,endurance,and description were effective positive predictors of the academic possible selves,with a total explanation rate of 33.6%.Conclusion:There were close relationships among the physical self,the level of mindfulness,and the academic possible *** physical self-description and high level of mindfulness could help individuals develop a positive attitude toward their academic possible selves.

关键词： freshman nursing students physical self mindfulness academic possible selves medical school

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Face Detection under Complex Background and Illumination

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Journal of Electronic Science and Technology 2015年第1期13卷 78-82页

作者： Shao-Dong Lv Yong-Duan Song mei Xu Cong-Ying Huang School of Energy Science and Engineering University of Electronic Science and Technology

For face detection under complex background and illumination, a detection method that combines the skin color segmentation and cost-sensitive Adaboost algorithm is proposed in this paper. First, by using the characteristic of human skin color clustering in the color space, the skin color area in YC b C r color space is extracted and a large number of irrelevant backgrounds are excluded; then for remedying the deficiencies of Adaboost algorithm, the cost-sensitive function is introduced into the Adaboost algorithm; finally the skin color segmentation and cost-sensitive Adaboost algorithm are combined for the face detection. Experimental results show that the proposed detection method has a higher detection rate and detection speed, which can more adapt to the actual field environment.

关键词： Adaboost cost-sensitive learning face detection skin color segmentation

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土体三轴试验固结过程解析解

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岩土力学 2016年第4期37卷 943-947,956页

作者：陈志波王志文朱俊高梅国雄福州大学环境与资源学院资源与城乡建设系福建福州350116 国土资源部丘陵山地地质灾害防治重点实验室福建福州350116 福建省水土流失遥感监测评估与灾害防治重点实验室福建福州350116 河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210098 广西大学土木建筑工程学院广西南宁530004

三轴试验是获取土体强度和应力变形特性的一个重要室内试验手段。三轴试验中,排水固结阶段试样的孔压消散及固结完成情况是非常重要的两个核心要素,它是进行后续剪切试验的基础和依据。基于等应变假设,推导了土体三轴剪切试验排水固结... 详细信息

三轴试验是获取土体强度和应力变形特性的一个重要室内试验手段。三轴试验中,排水固结阶段试样的孔压消散及固结完成情况是非常重要的两个核心要素,它是进行后续剪切试验的基础和依据。基于等应变假设,推导了土体三轴剪切试验排水固结过程的解析解,以用于分析整个排水固结过程的孔压消散和固结完成程度。针对室内三轴固结排水(CD)试验,利用所推导的解析解对其排水固结过程的孔压和固结度进行了验算对比。结果表明,解析解计算得到的固结度和孔压消散曲线与室内三轴剪切试验的相应曲线吻合得较好,说明解析解可应用于三轴剪切试验排水固结过程分析。

关键词：三轴试验三轴固结排水(CD)试验固结过程孔压消散排水曲线

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From Basin Black Shales to Platform Carbonate Rocks:A Study on Sequence Stratigraphy for the Lower Cambrian of the Upper-Yangtze Region in South China

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Acta Geologica Sinica(English Edition) 2007年第5期81卷 739-755页

作者： mei Mingxiang MA Yongsheng ZHANG Hai MENG Xiaoqing CHEN Yonghong State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 School of Earth Sciences and Resources China University of Geosciences Beijing 100083 Department of Oil-Fields China Petrochemical Corporation Beijing 100029

In the Upper-Yangtze region, especially in Guizhou Province and its adjacent areas, the Lower Cambrian is well developed and is marked by a succession from black shales of the basin facies to carbonate rocks of the platform facies. The drowning event of the platform occurring at the turn from Sinian to Cambrian resulted in a set of black shales, i.e. the Niutitang Formation, which makes up the bottom part of the Lower Cambrian. With the shoaling of the sedimentary environment, a set of carbonate rocks, i.e. the Qingxudong Formation, was formed in the top part of the Lower Cambrian. Thus, the Lower Cambrian in the study area makes up one second-order sequence that can be further subdivided into five third-order sequences, and forms a regularly cyclic succession of transgression-regression. There is a regularly vertical stacking pattern for the third-order sequences in the second-order sequence. From bottom to top, the succession of the ＂CS （condensed section）＋HST （high-stand system tract）＂ of the third-order sequences is changed into the succession of the ＂TST （transgressive system tract）＋CS＋HST＂. Correspondingly, the drowning-type sequence boundary is changed into the exposure-type one. Therefore, both the second-order and the third-order sequences have similar sedimentary-facies architectures. A concomitant with these temporal changes, the Lower Cambrian with a thickness of 1000 m that contains five third-order sequences is changed into a condensed succession that cannot identify third-order sequences toward the southeast with the deepening of the sedimentary environment. According to the elementary features of the third-order sequences, i.e. the regularity o sedimentary-facies successions in space and the synchronism of sedimentary-environment changes in time, the detailed division of the third-order sequences at main logged sections in different paleogeographical background becomes the basis to establish the sequence-stratigraphic framework that can demonstrate

关键词： sequence-stratigraphy Lower Cambrian Upper-Yangtze region South China

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