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Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

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Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： Feng Ren Zhuang-Zhuang Liang Ming-Xin Niu chen-Yang hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic *** new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability.

关键词： Polyester Polyether Alternative copolymer Ring-opening polymerization

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Knockdown of specific cuticular proteins analogous to peritrophin 3 genes disrupt larval and ovarian development in Bactrocera dorsalis(Diptera:Tephritidae)

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Insect Science 2021年第5期28卷 1326-1337页

作者： Qiu-Li Hou Er-hu chen Wei Dou Jin-Jun Wang Key Laboratory of Entomology and Pest Control Engineering College of Plant ProtectionSouthwest UniversityChongqing 400715China College of Horticulture and Plant Protection Yangzhou UniversityYangzhouJiangsu 225009China

Cuticular proteins(CPs)are critical components of the insect cuticle and play important roles in maintaining normal insect development and defense against various environmental *** oriental fruit fly(Bactrocera dorsalis)is one of the most destructive pests worldwide,and its eight CPs analogous to peritrophin 3(BdCPAP3)family genes have been identified in our prev ious *** the present study,we further explored the possible roles of CPAP3 genes in *** *** sequence of BdCPAP3 genes contained three conserved ChtBD2(chitin-binding)*** and temporal expression patterns revealed that the four BdCPAP3 genes(BdCPAP3-AI,B,E,and E2)might play important roles in larval pupariation of ***,treatment with a juvenile hormone analog(methoprene)significantly restricted expression of these four CPAP3 genes,whereas treatment with 20-hydroxy-ecdysone induced *** RNA interference(RNAi)results revealed that down-regulated CPAP3 genes led to signif-icant delay of pupariation,and injection of dsBdCPAP3-E into 5-d-old *** larvae caused approximately 40%***,we also confirmed that BdCPAP3-D2 was involved in *** ovarian *** study showed that some specific CP4P3 genes had crucial roles in *** development,and these CP genes could be used as potential targets to control this pest via RNAi.

关键词： Bactrocera dorsalis CPAP3 family expression patterns larval-pupal tran-sition ovarian development

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Paroxysmal speech disorder as the initial symptom in a young adult with anti-N-methyl-D-aspartate receptor encephalitis: A case report

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World Journal of Clinical Cases 2022年第24期10卷 8648-8655页

作者： Chuan-chen hu Xiao-Ling Pan Mei-Xia Zhang Hong-Fang chen Department of Neurology The Affiliated Jinhua HospitalSchool of MedicineZhejiang UniversityJinhua 321000Zhejiang ProvinceChina

BACKGROUND Anti-N-methyl-D-aspartate receptor(anti-NMDAR)encephalitis is a treatable but frequently misdiagnosed autoimmune *** dysfunction,as one of the common manifestations of anti-NMDAR encephalitis,is usually reported as a symptom secondary to psychiatric symptoms or seizures rather than the initial symptom in a paroxysmal *** report a case of anti-NMDAR encephalitis with paroxysmal speech disorder as a rare initial manifestation,and hope that it will contribute to the *** SUMMARY A 39-year-old man with anti-NMDAR encephalitis initially presented with paroxysmal nonfluent aphasia and was misdiagnosed with a transient ischemic attack and cerebral infarction *** patient subsequently presented with seizures,but no abnormalities were found on brain magnetic resonance imaging or *** fluid(CSF)analysis revealed mild pleocytosis and increased protein ***-NMDAR antibodies in serum and CSF were detected for a conclusive *** immunotherapy,the patient made a full *** This case suggests that paroxysmal speech disorder may be the presenting symptom of anti-NMDAR encephalitis in a young patient.

关键词： Anti-N-methyl-D-aspartate receptor encephalitis Autoimmune disease Paroxysmal speech disorder Seizure Immunotherapy Case report

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Effects of Soil Water Content on Cotton Root Growth and Distribution Under Mulched Drip Irrigation

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Agricultural Sciences in China 2009年第6期8卷 709-716页

作者： hu Xiao-tang, chen hu, WANG Jing, MENG Xiao-bin and chen Fu-hong Agricultural College, Shihezi University, Shihezi 832003, P.R.China Agricultural College Shihezi University Shihezi 832003 P.R. China

The relation between soil water content and the growth of cotton root was studied for the scheme of field water and cotton yield under mulched drip irrigation. Based on the field experiments, three treatments of soil water content were conducted with 90%, 75%θf, and 60%θf （θfis field water capacity）. Cotton roots and root-shoot ratio were studied with digging method, and the soil moisture was observed with TDR （time domain reflector）, and cotton yield was measured. The results indicated that the growth of cotton root accorded with Logistic growth curve in the three treatments, the cotton root grew quickly and its weight was very high under 75%θf because of the suitable soil water condition, while grew slowly and its weight was lower under 90%θf due to water moisture beyond the suitable condition, and the root weight was in between under 60%θf For the three water treatments, the cotton root weight decreased with soil depth, and decreased more significantly in deeper soil layer with the soil moisture increasing. And the ratio of cotton root weight in 0-30 cm soil layer to the total root weight was the highest under 75%θf. The cotton root system was distributed mainly in the soil of narrow row and wide row mulched with plastic film, and little in the soil outside plastic film. The weight of cotton root was the highest in the soil of narrow row or wide row mulched with plastic film under 75%θf. Root-shoot ratio decreased with the soil moisture increasing. The soil water content affected cotton yields, and cotton yield was the highest under 75%θf. The higher soil moisture level is unfavorable to the growth of cotton root system and yield of cotton under mulched drip irrigation.

关键词： mulched drip irrigation cotton (Gossypium hirsutum L.) soil water content root

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Facile Synthesis of Polyisothioureas via Alternating Copolymerization of Aziridines and Isothiocayanates

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Chinese Journal of Polymer Science 2024年第3期42卷 292-298,I0005页

作者： Hao-Tian Zhang Ming-Xin Niu Qi Zhang chen-Yang hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Materials Science and Engineering Jilin UniversityChangchun 130025China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Isothiourea is an important class of sulfur-containing molecules showing unique catalytic and biological activities. As such,polyisothiourea is envisioned to be an interesting type of polymer that potentially exhibits a number of interesting properties. However, there is no access to synthesizing well-defined polyisothiourea, and currently isothiourea-containing polymers are mainly prepared by immobilizing onto other polymer's side chain. Herein, we report the first facile synthesis of polyisothioureas via alternating copolymerization of aziridines and isothiocayanates. Mediated by the catalytic system of phosphazene superbases/alcohol, a broad scope of aziridines and isothiocayanates could be transformed into polyisothioureas with adjustable substitutions(11 examples). The structures of obtained polyisothioureas were fully characterized with ^(1)H-NMR, ^(13)C-NMR, and ^(1)H-^(13)C HMBC NMR. Moreover, the polyisothioureas show tunable thermal properties depending on substitutions on the isothiourea linkages. The novel structure of these polyisothioureas will enable a powerful platform for the discovery of nextgeneration functional plastics.

关键词： Polyisothioureas Alternative copolymer Aziridines Isothiocayanates

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Protective effects of ginkgo biloba leaves extract on peroxide-induced oxidative stress damage in PC12 cells

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Neural Regeneration Research 2007年第6期2卷 369-371页

作者： Weiqiang chen Taiping hu Ying Liu Department of Pathophysiology Guangdong Pharmaceutical College Guangzhou 510006 Guangdong Province China

BACKGROUND： Extracts of ginkgo biloba leaves （EGB） and its metabolites have been reported to enhance brain function and nerve behavior. It has also been hypothesized that they can protect neurons from oxidative stress. OBJECTIVE： To investigate protective effects of EGB on peroxide （H2O2）-induced oxidative stress damage in PC12 cells. DESIGN： Observational contrast study. SETTING： Department ofPathophysiology, Guangdong Pharmacological College. MATERIALS： EGB was provided by Xi＇an Fujie Biotechnological Development Company; 1640 culture medium, methylthiazolyl tetrazolium （MTT）, trypsin and dimathyl sulfoxide （DMSO） by Sigma Company; PC12 cell strain by Cell Center of Medical College of Zhongshan University; calf serum by Hangzhou Sijiqing Bioengineering Company; lactate dehydrogenase （LDH） kit by Nanjing Jiancheng Bioengineering Research Institute. METHODS： The experiment was carried out in Department of Cell Biology of Guangdong Pharmacological College from June to December 2005. ①Cell culture： PC12 cells were cultured in 1640 medium containing 200 g/L fetal calf serum. The cells were diluted to 1 × 10^7 L^-1 and washed every two days. Those cells were used to experiment until they grew in logarithm on solid wall. ② Grouping and intervention： PC12 cells （1 × 10^8L^-1） were plated in 96-well plates with the density of 200 μ L/hole and divided into three groups： normal control group （routinely adding media）, H2O2 group （treating with media and H2O2 for 20 hours） and EGB group （adding media, 100μmol/L EGB and 100 μmol/L H2O2）. ③ MTT assay： PC12 cells （1 × 10^8L^-1） were plated in 96-well plates and divided into three groups with 8 holes for each group. Under sterile condition, cells were added with 5 g/L MTT （100μL） and cultured for 4 hours. And then, 200 μ L DMSO fluid was added and shaken for 30 minutes until blue crystal products formed were dissolved soundly ④ Experimental evaluation： Absorbance （A） at 630 nm was measured and LDH activity was measured at the same

关键词： PC12 cell H2O2: extracts of ginkgo biloba leaves

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Copolymerization of PO/CO_(2)and Lactide by a Dinuclear Salen-Cr(Ⅲ)Complex:Gradient and Random Copolymers with Modificable Microstructure

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Chinese Journal of Polymer Science 2022年第9期40卷 1028-1033页

作者： Zhuang-Zhuang Liang Xiang Li chen-Yang hu Ran-Long Duan Xian-Hong Wang Xuan Pang Xue-Si chen Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Copolymerization of propylene oxide(PO)/carbon dioxide(CO_(2))and lactide(LA)is achievable to form new copolymers,combining the advantages of both poly(propylene carbonate)(PPC)and polylactide(PLA).In this study,we designed a dinuclear Salen-Cr(Ⅲ)complex,which showed higher efficiency for copolymerization of PO/CO_(2)and LA than that of mononuclear Salen-Cr(Ⅲ)***,we successfully obtained gradient and random copolymers of PPC-PLA in one ***,by adjusting reaction temperature,block ratios of PPC/PLA in copolymers were controllable(block ratio of PPC/PLA=1.0 at 40℃,while block ratio of PPC/PLA=0.5 at room temperature).While increasing the reaction temperature to 60℃,conversion of LA was much faster than that of PO so that gradient copolymers were obtained.

关键词： Dinuclear Salen-Cr(Ⅲ)complex Poly(propylene carbonate) Polylactide Gradient and random copolymers

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Annexin A1 Mimetic Peptide AC2-26 Inhibits Sepsis-induced Cardiomyocyte Apoptosis through LXA4/PI3K/AKT Signaling Pathway

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Current Medical Science 2018年第6期38卷 997-1004页

作者： Li ZHANG Yan-lei ZHENG Rong-hua hu Li Zhu chen-chen hu Fei chenG Shi LI Jian-guo LI Intensive Care Unit Zhongnan Hospital of Wuhan UniversityWuhan 430071China Intensive Care Unit Hubei Cancer HospitalWuhan 430079China

The aim of the present study was to explore the effects of annexin A1(ANXA1) mimetic peptide AC2-26 on sepsis-induced cardiomyocyte apoptosis in vivo and in vitro and the underlying *** the in vivo study,a rat septic model was established by the cecal ligation and puncture (CLP).The rats were divided into control group,sepsis group and AC2-26 *** rats in the AC2-26 group were intraperitoneally injected with AC2-26(1mg/kg)2h before CLP,and those in the control group and sepsis group were injected with the same volume of normal *** myocardial tissue was examined by hematoxylin and eosin (HE)staining and transmission electron microscopy (TEM).Furthermore,myocardial apoptosis was measured by terminal dUTP nick end-labeling (TUNEL)*** the in vitro study,H9C2cells were cultured and divided into three groups:control group,in which cells were only given the basic culture medium;LPS group,in which cells were treated with 10μg/mL LPS;AC2-26 group,in which cells were treated with 0.5μmol/L AC2-262h before 10μg/mL LPS was *** apoptosis of H9C2 cells was detected by flow *** levels of lipoxin A4 receptor (LXA4),phosphoinositide3-kinase (PI3K)and protein kinase B (PKB or AKT)protein were measured by Western blotting, the activity of NF-KB and the level of TNF-α by ELISA and the activities of caspase-3/8by using the caspase activity *** in vivo study showed that the myocardial pathological damage and myocardial ultrastructural damage were significantly alleviated and the myocardial apoptosis significantly decreased in the AC2-26 group as compared with the sepsis group (P<0.05 for all). The in vivo study revealed that the apoptosis of H9C2 cells was profoundly ameliorated in the AC2-26 group relative to the sepsis group (P<0.05).The protein expression levels of LXA4 were significantly up-regulated,and those of PI3K and AKT prominently down-regulated in the AC2-26 group when compared with those in the LPS group (P<0.05 for all).The ac

关键词： sepsis AC2-26 H9C2 apoptosis inflammation

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Hydrological Response of Populus euphratica Olve. Radial Growth in Ejinaa Banner, Inner Mongolia

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Journal of Integrative Plant Biology 2007年第2期49卷 150-156页

作者： Pu-Xing Liu Jian-Feng Peng Fa-hu chen Center for Arid Environment and Paleoclimate Research Key Laboratory of Western China's Environmental System Under Ministry of Education Lanzhou University Lanzhou 730000 China College of Geography and Environment Sciences Northwest Normal University Lanzhou 730070 China

Populus euphratlca Olve. is a dominant tree species in Ejlnaa Oasis of the lower reaches of the Helhe River, inner Mongolia, China. In recent years, the population of this species has shown signs of degradation that are suggested to be probably associated with the decrease of surface water. In this study, the history of river runoff In this region was examined with a dendrochronological study of P. euphratica from four sites. It Is found that tree-ring widths In the all sites have negative correlation with runoffs of all months at the Zhengylxla hydrological station. Principal component （PC） analysis of the tree-ring chronologies shows that the first PC （PC1） accounts for 49.98% of the total variances. The first PC Is found to have a significantly negative correlation with runoffs In March and April （- 0.52 and - 0.43, respectively, P 〈 0.05）. This negative correlation might be related to variations In the depth of underground water.

关键词： dendrohydrology lower reaches of Heihe River Populus euphratica Principal Component Analysis radial growth response model.

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Contactin 1: A potential therapeutic target and biomarker in gastric cancer

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World Journal of Gastroenterology 2015年第33期21卷 9707-9716页

作者： De-hu chen Ji-Wei Yu Bo-Jian Jiang Department of General Surgery Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of Medicine

Despite advances in diagnosis and treatment,gastric cancer remains one of the most common malignant tumors worldwide,and early diagnosis remains a *** lack of effective methods to detect these tumors early is a major factor contributing to the high mortality in patients with gastric cancer,who are typically diagnosed at an advanced ***,the early detection of metastases and the curative treatment of gastric cancer are difficult to achieve,and the detailed mechanisms remain to be fully ***,the identification of valuable predictive biomarkers and therapeutic targets to improve the prognosis of patients with gastric cancer is becoming increasingly *** 1(CNTN1),a cell adhesion molecule,is a glycosylphosphatidylinositolanchored neuronal membrane protein that plays an important role in cancer *** expression of CNTN1 is upregulated in primary lesions,and its expression level correlates with tumor metastasis in cancer *** current evidence reveals that the functions of CNTN1 in the development and progression of cancer likely promote the invasion and metastasis of cancer cells via the VEGFC/FLT4 axis,the RHOAdependent pathway,the Notch signaling pathway and the epithelial-mesenchymal transition ***,CNTN1 may be a novel biomarker and a possible therapeutic target in cancer treatment in the near future.

关键词： Cancer/neoplasms Stomach Contactin 1 Metastasis Mo

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