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Radical azidation as a means of constructing C(sp^(3) )-N_(3) bonds

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Green Synthesis and Catalysis 2020年第2期1卷 86-120页

作者： Liang Ge mong-feng chiou Yajun Li Hongli Bao Key Laboratory of Coal to Ethylene Glycol and Its Related Technology State Key Laboratory of Structural ChemistryCenter for Excellence in Molecular SynthesisFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China

The azido group is found in large numbers of natural products,drugs,biochemicals and materials and to date,many elegant and useful methods for the synthesis of organic azides and their transformations have been *** this review,we provide a summary of the state of the art of radical azidation for the construction of C(sp^(3) )-N_(3) *** is a specific emphasis on the synthetic reactions involving C(sp^(3))-H azidation,decar-boxylative azidation and difunctionalized azidation of *** review will be useful to those working in this field and hopefully could inspire further development of radical azidation reactions.

关键词： Radical Azidation Aliphatic azide C(sp_(3))-H azidation Difunctionalization Decarboxylative azidation

Tremella polysaccharide mitigates high fat diet-induced anxiety-like behavior through the microbiota-gut-brain axis

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Food Science and Human Wellness 2024年

作者： Haicui Wu Shuyu Chen Wenxiu Zhang Yuqing Lu Jiayi Zheng Jinhui Chang Jiachi chiou Research Institute for Future Food The Hong Kong Polytechnic University Shenzhen Key Lab for Food Biological Safety Control The Hong Kong Polytechnic University Shenzhen Research Institute Bo InnoHealth Biotechnology Company Limited Hong Kong Science Park Department of Food Science and Nutrition The Hong Kong Polytechnic University Department of Neurology The Second Affiliated Hospital of Guangzhou University of Chinese Medicine

High-fat diet (HFD) consumption induces gut microbiota dysbiosis and neuropsychiatric disorders， including anxiety. Previous research found that Tremella polysaccharide (TP) exhibited neuroprotective effects in vitro and in vivo. This study aimed to investigate the beneficial effects of TP on HFD-induced anxiety-like behaviors and elucidate the underlying mechanisms from the point view of the microbiota-gut-brain axis. Two groups of HFD-induced obese mice were orally gavaged with low dose (TPL， 40 mg/kg) and high dose (TPH， 400 mg/kg) of TP. A 12-week administration of TPH could significantly improve anxiety-like behaviors in HFD mice. In the hippocampus， microglia activation， the expression of blood-brain barrier (BBB) markers， and the levels of two neurotransmitters (serotonin and norepinephrine) were countered by TPH in mice consuming HFD. Furthermore， TPH improved the intestinal permeability and immune response of the enterocytes in HFD-fed mice. The gut microbiota dysbiosis induced by HFD was also rebalanced by TP treatments， especially in Proteobacteria and its lower taxa. The correlational analysis also suggested that shifts of some microbial genera were closely associated with body weight and the parameters of behavioral tests. Interestingly， fecal microbiota transplantation (FMT) results indicated that fecal microbiota from TPH-treated obese mice could prevent HFD-induced anxiety-like behaviors， suppressing microglia activation and intestinal permeability. In conclusion， the present study indicated that TP intake is a promising dietary intervention strategy to prevent HFD-induced anxiety via the microbiota-gut-brain axis.

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酞菁铁催化烯烃自由基膦叠氮化反应:利用叠氮快速转移合成膦叠氮的温和方法

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Chinese Journal of Catalysis 2021年第10期42卷 1634-1640页

作者：马晓旭邱盟峯葛亮李晓岩李亚军吴莉鲍红丽中国科学院福建物质结构研究所分子合成卓越中心结构化学重点实验室煤制乙二醇及相关技术重点实验室福建福州350002 武汉工程大学化学与环境工程学院湖北武汉430205 中国科学院大学北京100049

含氮和磷原子的化合物是生命系统中不可缺少的组成部分,由于其独特的化学、生物和物理性质,已被广泛应用于农业化学、材料科学和制药学.如果一个有机化合物同时含有氮和磷原子,它可能因为胺和膦/磷酸盐基团的协同作用而具有额外的功能.2... 详细信息

含氮和磷原子的化合物是生命系统中不可缺少的组成部分,由于其独特的化学、生物和物理性质,已被广泛应用于农业化学、材料科学和制药学.如果一个有机化合物同时含有氮和磷原子,它可能因为胺和膦/磷酸盐基团的协同作用而具有额外的功能.2015年赵玉芬院士和唐果教授报道了一例自由基叠氮膦酰化的例子,该反应虽然有效,但因需使用化学剂量的氧化性自由基引发剂Mn(OAc)_(3)·2H_(2)O,因此,有必要发展一种更环保经济的方法.本文报道了铁催化烯桂的分子间自由基膦叠氮化反应.该方法使用了微量的催化剂,通过自由基接力与叠氮基团转移实现分子间自由基膦叠氮化反应.实验先进行条件筛选,考察了催化剂类型、催化剂用量、氧化剂类型、溶剂和温度对反应的影响,确定以瞅菁铁为催化剂,叔丁基过氧化氢(TBHP)为引发剂,乙睛为溶剂,苯乙烯、叠氮基三甲基硅烷、二苯基膦酰为模板反应底物为最佳条件,实现了二苯基膦酰对烯炷的自由基膦酰基叠氮化反应.在最优条件下进行底物拓展,制备得到27种膦叠氮化合物,产率为23%〜88%.以制得的膦叠氮产物为起始原料,通过叠氮还原和Click反应制备得到三种衍生物,产率为82%-97%,可作为药物合成中间体进行下一步研究.本文还进行了机理实验和理论计算.在自由基钟实验和自由基捕获实验中,通过两种不同速率的自由基开环反应与自由基捕获反应证实了反应的自由基路径.质谱检测到酞菁铁径基(PcFe^(Ⅲ)OH)和酞菁铁叠氮(PcFe^(Ⅲ)N_(3))的存在.采用密度泛函理论计算了不同自旋态下的酞菁铁(PcFe),以确定可能的催化剂种类,并计算出三重态^(3)pcFe最稳定.从三重态^(3)PcFe开始计算铁催化叔丁基过氧化氢的单电子转移,并计算了从叔丁氧基自由基开始的自由基接力,证实了膦酰节基自由基的形成是最有利的途径;研究结果发现膦酰节基自由基能与^(4)PcFe(N3)反应,发生叠氮基团转移生成目标产物.在叠氮基团转移计算中,考察了四种合理的途径,分别是节基在三重态或五重态势能面接近叠氮基团的内部或端位氮原子(N_(i)和N_(t)).结果表明,叠氮基团从叠氮基酞菁铁(Ⅲ)物种(Pc^(Ⅲ)N_(3))转移到节基自由基的活化能(4.8 kcal/mol)极低.据此催化循环机理可能为:酞菁铁首先与叔丁基过氧化氢发生单电子转移形成酞菁铁径基中间体及叔丁氧自由基;然后,二苯基膦酰的氢原子被叔丁氧自由基攫取生成二苯基膦酰自由基,并加成至苯乙烯形成节基自由基.同时,酞菁铁羟基中间体与HN_(3)进行配体交换形成酞菁铁叠氮中间体,最后与节基自由基进行叠氮基团转移生成产物,并重新生成酞菁铁(Ⅱ).本文证实了铁催化叠氮化反应的自由基基团转移机理(外球机理),因为很难想象如何在酞菁铁的同侧同时加成叠氮与节基基团,通过生成高价铁物种(PcFe-N_(3)·)的内球机理得到产物.该工作将有助于启发更多的金属催化机理研究.

关键词：酞菁铁磷酰基叠氮化双官能团化自由基基团转移密度泛函理论计算

Reversible Data Hiding Based on Greedy Pairing Prediction-Error Expansion

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Journal of Electronic Science and Technology 2022年第3期20卷 294-304页

作者： Yi-Nan Lin Gwo-Jen chiou Cheng-Ying Yang Victor R.L.Shen Chiao-Chih Lai the Department of Electronic Engineering Ming Chi University of TechnologyNew Taipei 243303 the Department of Electrical Engineering “National Formosa University”Yunlin 632301 the Department of Computer Science University of TaipeiTaipei 10048 the Department of Computer Science and Information Engineering “National Taipei University”New Taipei 23741 the Department of Information Management Chaoyang University of TechnologyTaichung 413310 Acer Company Taipei 221

Reversible data hiding(RDH)is a method to embed messages into an image that human eyes are difficult to recognize the differences between the original image and the embedded *** method needs to make sure that the original image and the embedded information can be exactly *** prediction-error expansion(PEE)is a successful way to realize ***,it is fixed when pairing the conventional twodimensional prediction-error histogram(2D-PEH).So,the embedding capacity(EC)and embedding distortion(ED)are not *** this study,we propose a method called greedy pairing prediction-error expansion(GPPEE)based on pairwise RDH and demonstrate GPPEE can achieve a more efficient embedding goal and reduce ED.

关键词： Greedy pairing prediction-error expansion(GPPEE) prediction-error expansion(PEE) reversible data hiding(RDH) two-dimensional prediction-error histogram(2D-PEH)

Massive pulmonary embolism in Klippel-Trenaunay syndrome after leg raising:A case report

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World Journal of Clinical Cases 2023年第17期11卷 4133-4141页

作者： Chih-Yu Lo Kuen-Bao Chen Li-Kuei Chen Chiuan-Shiou chiou Department of Anesthesiology China Medical University HospitalTaichung 40447Taiwan Department of Anesthesiology Pain Service and Critical Care Medicine China Medical University HospitalTaichung 40447Taiwan

BACKGROUND Klippel-Trenaunay syndrome(KTS)is a rare congenital disorder characterized by a combination of capillary malformations,soft-tissue or bone hypertrophy,and varicose veins or venous *** syndrome predisposes patients to hypercoagulable states,including venous thromboembolism and pulmonary embolism(PE).CASE SUMMARY A 12-year-old girl with KTS was scheduled excision of verrucous hyperkeratosis in the left foot and posterior aspect of the left leg and left thigh and excision of a cutaneous hemangioma in the right *** induction,the surgeon elevated the patient’s leg for sterilization,whereupon she experienced a massive PE and refractory cardiac *** membrane oxygenation(ECMO)was performed after prolonged resuscitation,and she had a return of spontaneous *** this episode,the patient was discharged without any neurologic *** The mechanism of PE,a lethal disease,involves a preexisting deep vein thrombosis that is mechanically dislodged by compression or changing positions and travels to the pulmonary ***,patients predisposed to PE should be prescribed prophylactic *** the patient has unstable vital signs,resuscitation should be started immediately,and extracorporeal cardiopulmonary resuscitation should be considered in settings with existing ECMO protocols,expertise,and *** of PE in patients with KTS while leg raising for sterilization is critical.

关键词： Klippel-Trenaunay syndrome Pediatric Pulmonary embolism Anesthesia Case report

Efficacy and safety of anti-vascular endothelial growth factor agents on corneal neovascularization: A meta-analysis

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World Journal of Clinical Cases 2023年第30期11卷 7337-7349页

作者： Shih-Chung Lai El-Wui Loh Du-I chiou Chien-Tai Hong Department of Ophthalmology Shuang Ho HospitalNew Taipei City 23561TaiwanChina Center for Evidence-Based Health Care Department of Medical ResearchTaipei Medical University Shuang Ho HospitalNew Taipei City 23561TaiwanChina Cochrane Taiwan Taipei Medical UniversityTaipei 110TaiwanChina Graduate Institute of Clinical Medicine College of MedicineTaipei Medical UniversityTaipei 110TaiwanChina Department of Medical Imaging Taipei Medical University Shuang Ho HospitalNew Taipei City 23561TaiwanChina Department of Neurology Taipei Medical University-Shuang Ho HospitalNew Taipei 23561TaiwanChina

BACKGROUND Corneal neovascularization(CoNV)is the second major cause of *** endothelial growth factor(VEGF)inhibitors,e.g.,bevacizumab,have been used to prevent *** We conducted an updated systematic review and meta-analysis of clinical trials to examine the efficacy and safety of anti-VEGF in *** A literature search was conducted using three electronic *** difference(MD),standard mean difference(SMD),and relative risk(RR)are used to estimate the effect *** Nine randomized controlled and three non-randomized trials were *** pooled results demonstrated a significant reduction of CoNV area/Length(SMD=-1.17,95%CI:-1.58 to-0.75),best corrected visual acuity(MD=-0.54,95%CI:-0.91 to-0.17),and graft rejection(RR=0.44,95%CI:0.24 to 0.8)and failure(RR=0.39,95%CI:0.19 to 0.78)rates in the anti-VEGF group than the placebo group.A non-significant reduction of the epithelial defect was also observed in the bevacizumab group compared with the placebo(RR=0.56,95%CI:0.30 to 1.06).Compared with a placebo,the unsynthesizable trials also support that bevacizumab improves visual acuity,CoNV,graft rejection,and failure *** reporting other comparisons revealed the superiority of combined remedy with bevacizumab compared to other treatments in reducing *** Anti-VEGF agents,mainly bevacizumab,are an effective and safe treatment for CoNV of all causes and prevent corneal graft rejection and failure in corneal transplantation.

关键词： Efficacy Safety Anti-vascular endothelial growth factor agents Corneal neovascularization Bevacizumab

Cauda equina syndrome caused by the application of DuraSeal^(TM) in a microlaminectomy surgery:A case report

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World Journal of Clinical Cases 2022年第30期10卷 11178-11184页

作者： Kuei-Lin Yeh Szu-Hsien Wu chiou-Shann Fuh Yi-Hung Huang Chu-Song Chen Shing-Sheng Wu Department of Orthopaedics Ditmanson Medical Foundation Chia-Yi Christian HospitalChia-Yi City 600Taiwan Department of Computer Science and Information Engineering National Taiwan UniversityTaipei 10617Taiwan Department of Long-Term Care and Management WuFeng UniversityChiayi County 621303Taiwan Department of Physical Medicine and Rehabilitation Taipei Veterans General HospitalTaipei 11217Taiwan Department of Orthopaedics Shin Kong Wu-Ho Su Memorial HospitalTaiepi 111Taiwan

BACKGROUND The management of dural tears is *** a massive dura can be repaired with absorbable suture lines,cerebrospinal fluid leakage can be attenuated by dural sealant when an unintended tiny durotomy occurs *** is often used because it can expand to seal *** case emphasizes the need for caution when DuraSeal is used as high expansion can cause complications following *** SUMMARY A 77-year-old woman presented with L2/3 and L3/4 lateral recess *** underwent microlaminectomy,foraminal decompression,and disk height restoration using an IntraSPINE~? device.A tiny incident durotomy occurred intraoperatively and was sealed using DuraSeal ^(TM).However,decreased muscle power,urinary incontinence,and absence of anal reflexes were observed *** magnetic resonance imaging revealed fluid collection causing thecal sac indentation and central canal *** exploration revealed that the gel-like DuraSeal had entrapped the hematoma and,consequently,compressed the thecal sac and nerve *** we removed all DuraSeal ^(TM) and exposed the nerve root,the patient’s neurological function did not recover *** DuraSeal expansion must not be *** in neurological status require investigation for cauda equina syndrome due to expansion.

关键词： Cauda equina syndrome DuraSeal Microlaminectomy Spinal stenosis Case report

线粒体靶向的近红外HClO/ClO^(-)荧光探针的研究进展

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应用化学 2022年第3期39卷 407-424页

作者：黄蕊叶长青李亚军邱盟峯李达谅鲍红丽福建师范大学生命科学学院福州350117 中国科学院福建物质结构研究所中国科学院煤制乙二醇及相关技术重点实验室福州350002

HClO/ClO^(-)作为细胞质中一种重要的活性氧(ROS),源自线粒体,参与各种生理和病理过程,因此快速有效检测HClO/ClO^(-)具有重要的生物学及生理学意义。荧光分析法因其灵敏度高、响应时间快、选择性高、成本低和操作简便等优点而备受关注... 详细信息

HClO/ClO^(-)作为细胞质中一种重要的活性氧(ROS),源自线粒体,参与各种生理和病理过程,因此快速有效检测HClO/ClO^(-)具有重要的生物学及生理学意义。荧光分析法因其灵敏度高、响应时间快、选择性高、成本低和操作简便等优点而备受关注。更重要的是,使用荧光探针可以在体外和体内可视化检测。近年来,为了研究HClO/ClO^(-)在细胞中的作用,已发展了一些靶向线粒体的荧光HClO/ClO^(-)探针。其中,发射波长位于短波区域的探针存在背景荧光强、组织穿透性差等不足,因此,开发具有远红外至近红外发射的HClO/ClO^(-)探针具有重要意义。本文围绕用于检测HClO/ClO^(-)的线粒体靶向近红外荧光探针的最新动态展开讨论,将探针检测HClO/ClO^(-)的反应类型分为不饱和双键的氧化、硫醚的氧化、氨基或酰肼的氧化和多位点的氧化等几个类别进行了归纳总结,希望为新一代高效灵敏、生物兼容性好的靶向性HClO/ClO^(-)荧光探针的发展提供一定的帮助。

关键词：线粒体荧光探针近红外次氯酸

Effects of flavone on the oxidation-induced injury of retinal pigment epithelium cells

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International Journal of Ophthalmology(English edition) 2010年第2期3卷 99-103页

作者： George C Y chiou Institute of Ocular Pharmacology College of MedicineTexas A&M Health Science CenterCollege StationTX 77843USA

AIMTo investigate the effect of flavone on oxidation-induced injury in retinal pigment epithelium cells.

关键词： flavone age-related macular degeneration retinal pigment epithelium oxidation