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Synthesis and mesomorphism of diacetylene-bridged triphenylene discotic liquid crystal dimers

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Science China Chemistry 2009年第7期52卷 975-985页

作者： JI Hong ZHAO KeQing YU WenHao WANG BiQin hu pin College of Chemistry and Materials Science Sichuan Normal UniversityChengdu 610066China

Connecting two discotic mesogens via a spacer not only stabilizes the columnar mesophase but also leads to the formation of glass columnar phase, and therefore improves the physical properties of discotic liquid crystals as organic semiconductor. Here, we report the synthesis of eight diacetylene-bridged triphenylene discotic liquid crystal dimers, [C18H6(OC n H2n+1)4(OMe)O2C?C8H16?C≡C?]2, 3(n), (n = 4–8), [C18H6(OC6H13)5O2C?C8H16?C≡C?]2, 6 and [C18H6(OC6H13)5O?(CH2)m?C≡C?]2, 8(m), (m = 1, 3) by Eglinton coupling reaction. The thermotropic liquid crystal properties were studied by differential scanning calorimetry and polarized optical microscopy. The results are showed as follows: the length of peripheral alkyl chains of triphenylene influenced properties of liquid crystal dimers; dimers 3(n) (n = 5–8) and 6 had glass columnar phase, and no crystallization was observed above ?50°C for all the triphenylene dimers; compared with 3(6), 6 showed higher molecular symmetry, more stable columnar mesophase and wider mesophase range. The connecting group, length and rigidity of spacer had important influence on the mesomorphism of diacetylene-bridged triphenylene discotic liquid crystal dimers.

关键词： triphenylene discotic liquid crystal Eglinton coupling reaction liquid crystal dimer glass columnar phase

Enhancing sensitivity of microbial fuel cell sensors for low concentration biodegradable organic matter detection:Regulation of substrate concentration,anode area and external resistance

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Journal of Environmental Sciences 2021年第3期33卷 227-235页

作者： Yangyang Gao Sha Wang Fengjun Yin pin hu Xingzu Wang Yuan Liu Hong Liu Key Laboratory of Reservoir Aquatic Environment Chinese Academy of SciencesChongqing 400714China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China University of Chinese Academy of Sciences Beijing100049China

The relatively low sensitivity is an important reason for restricting the microbial fuel cell(MFC)sensors'application in low concentration biodegradable organic matter(BOM)*** startup parameters,including substrate concentration,anode area and external resistance,were regulated to enhance the sensitivity of MFC *** results demonstrated that both the substrate concentration and anode area were positively correlated with the sensitivity of MFC sensors,and an external resistance of 210Ωwas found to be optimal in terms of sensitivity of MFC *** MFC sensors had lower detection limit(1 mg/L)and higher sensitivity(Slope value of the linear regression curve was 1.02),which effectively overcome the limitation of low concentration BOM *** essential reason is that optimized MFC sensors had higher coulombic efficiency,which was beneficial to improve the sensitivity of MFC *** main impact of the substrate concentration and anode area was to regulate the proportion between electrogens and nonelectrogens,biomass and living cells of the anode *** external resistance mainly affected the morphology structure and the proportion of living cells of the *** study demonstrated an effective way to improve the sensitivity of MFC sensors for low concentration BOM detection.

关键词： Microbial fuel cell sensor High sensitivity Biodegradable organic matter Substrate concentration Anode area External resistance

Critical lower extremity ischemia after snakebite: A case report

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World Journal of Clinical Cases 2021年第26期9卷 7857-7862页

作者： Zi-Ying Lu Xiao-Dong Wang Jin Yan Xiao-Long Ni Si-pin hu Department of Vascular Surgery Tongde Hospital of Zhejiang ProvinceHangzhou 310000Zhejiang ProvinceChina

BACKGROUND Globally,the estimated annual incidence of snakebites is approximately 5 million,and approximately 100000 deaths occur from snakebites *** tissue reaction,haemorrhagic clotting disorder,nephrotoxicity,and neurotoxicity are very common effects of snake envenomation,but other rarer complications,such as thrombosis,may also occur as a result of underlying *** the treatment of snakebite patients,attention should be paid to the patient’s underlying diseases to avoid serious and catastrophic consequences secondary to *** SUMMARY We report a 69-year-old man with critical right lower extremity pain after left foot snakebite 10 d prior without intermittent claudication or atrial fibrillation *** was diagnosed with acute right lower extremity arterial thrombosis,which may have been caused by coagulopathy after snakebite and lower extremity atherosclerotic occlusive *** extremity computed tomography angiography at another hospital revealed that the aortoiliac and femoral arteries had neither filling defects nor atherosclerosis,but the right popliteal artery was occluded 2.3 cm below the tibial *** patient received emergency catheter-directed thrombolysis,but amputation was carried out 11 d after admission because the patient had been admitted to the hospital too late to save the *** Acute ischaemia of the lower extremity due to snakebite is a rare event,and physicians should bear in mind the serious complications that may occur,especially in patients with atherosclerotic disease.

关键词： Critical extremity ischaemia Snakebite Thrombosis Haematological abnormalities Case Report

Light-Mediated Spatiotemporally Dynamic Assembly of DNA Nanostructures in Living Cells Regulates Autophagy

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CCS Chemistry 2024年第6期6卷 1557-1570页

作者： Rui Zhang pin hu Yuwei Xu Ziqing Wang Dayong Yang Chi Yao Frontiers Science Center for Synthetic Biology Key Laboratory of Systems Bioengineering(MOE)School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350 Department of Chemistry State Key Laboratory of Molecular Engineering of PolymersShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsCollege of Chemistry and MaterialsFudan UniversityShanghai 200438

The assembly of exogenous artificial architectures inside cells can regulate a series of biological events,which heavily relies on the development of spatiotemporally controlled molecular assembly *** herein report a designer deoxyribonucleic acid(DNA)nanostructure that enables light-mediated spatiotemporally dynamic assembly in living cells and consequently achieves efficient regulation of cell *** DNA nanostructure was constructed from i-motif moiety-containing branched DNA,photocleavable bond-containing linker,and tumor cell-targeting *** cellular uptake mediated by aptamers,under the spatiotemporal control of both UV light and late endosomal/lysosomal acidic environments,disassembly/reassembly of DNA nanostructure occurred via two rationally designed routes,generating microsized DNA *** a result,autophagy was significantly enhanced with the increase of DNA assembly *** enhanced autophagy showed an impact on related biological *** system is expected to be a powerful tool for the regulation of intracellular events and cellular behaviors.

关键词： DNA nanotechnology DNA hydrogel self-assembly autophagy i-motif

Gene-like Precise Construction of Functional DNA Materials

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Accounts of Materials Research 2022年第1期3卷 42-53页

作者： Chi Yao Yuwei Xu pin hu Junhan Ou Dayong Yang Frontiers Science Center for Synthetic Biology Key Laboratory of Systems Bioengineering(MOE)Institute of Biomolecular and Biomedical EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350P.R.China

CONSPECTUS:Developing a new system of material chemistry is an important molecular foundation for the design and preparation of functional materials,which resembles the preparation of raw materials such as bricks for constructing a building that determines the quality of the ***,precisely controlling the synthesis processes and structures of functional materials always remains a grand *** is expected to propose a paradigm of“gene-like”precise construction to realize the rational synthesis of functional materials,i.e.,a“structure-function-application”principle for the precise *** the core genetic material of life,the DNA molecule is a bioactive macromolecule that can accurately encode genetic information and also can act as the generic molecular building block for the precise construction of functional *** this Account,we describe our work on the design and construction of functional DNA materials,to illustrate the principle of“gene-like”construction of functional DNA *** DNA molecule shows the unique advantages in the“gene-like”construction of functional materials,mainly including the precise arrangement of bases(monomers),the controllable design and assembly of structure,the precise transmission of sequence information,and customization of ***,the number and sequence of four deoxynucleotide monomers that constitute the DNA strand can be rationally designed and accurately ***,the sequence information on DNA endows the precise and efficient assembly of DNA molecules and ensures the precise regulation on the specific biological functions of functional DNA ***,the functions of DNA materials can couple with the biological environments,so as to achieve the predetermined *** on the scale of the constructed DNA materials,we categorize DNA materials into three classes:molecular scale,nanoscale,and *** the molecular scale,the representative material is branched

关键词： materials. precise synthesis

Expression of peroxisome proliferator-activated receptor γ,E-cadherin and matrix metalloproteinases-2 in gastric carcinoma and lymph node metastases

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Chinese Medical Journal 2007年第17期120卷 1498-1504页

作者： HE Qing CHEN Jie LIN Han-liang hu pin-jin CHEN Min-hu Department of Gastroenterology First Affiliated Hospital Sun Yat-sen University Guangzhou 510080 China Department of Pathology First Affiliated Hospital Sun Yat-sen University Guangzhou 510080 China

Background Peroxisome proliferator activated receptor γ （PPARγ） is a ligand-activated transcription factor. Activation of PPARγ has recently been demonstrated to inhibit various tumor cells growth, progression and metastasis. E-cadherin-mediated cell adhesion system is now considered to be an “invasion suppressor system” in cancer tissues. Matrix metalloproteinases-2 （MMP-2） is a prerequisite for metastasizing tumor cells. However their correlation is still unknown in gastric carcinoma. The aim of this study was to assess the expression of PPAR7, E-cadherin, MMP-2 and their correlation in gastric carcinoma and metastases. Methods Gastric carcinoma tissues and their corresponding lymph nodes with metastases and the adjacent non-tumor tissues were obtained from 54 patients with gastric cancer who underwent gastrectomy. Expression of PPARγ, E-cadherin and MMP-2 was assessed by immunohistochemical staining. Results The nuclear expression level of PPARγ in neoplastic cells was significantly lower than that in the normal controls （P〈0.001）, with the expression of PPARγ being weaker in primary tumors compared with that in metastases. In all neoplastic cells, E-cadherin was expressed with abnormal patterns （cytoplasm pattern, cytoplasm and membrane pattern or absent）, compared with normal cells where E-cadherin was expressed with a normal pattern （membrane pattern）. Compared with the normal tissues, the expression level of E-cadherin decreased in primary tumors and further decreased in metastases （P〈0.001）. Membrane staining of MMP-2 was detected in the foveolar epithelia of normal gastric mucosa, whereas predominant cytoplasm staining of MMP-2 was found in malignant tissues. The expression of MMP-2 was stronger in metastatic tissues than in primary tumors. In neoplastic foci the expression of PPARγ was negatively correlated with MMP-2 expression （P〈0.05）. However, there was no correlation between E-cadherin and PPARγ or MM P-2 expression. Conclusions Down-regulation

关键词： peroxisome proliferator-activated receptor γ, E-cadherin matrix metalloproteinases-2 gastric carcinoma metastases

Relationship between symptom response and esophageal pH level on standard dose of esomeprazole treatment for gastroesophageal reflux disease

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Chinese Medical Journal 2010年第15期123卷 2012-2017页

作者： PENG Sui XIONG Li-shou XIAO Ying-lian WANG An-jiang LIN Jin-kun hu pin-jin CHEN Min-hu Division of Gastroenterology & Hepatology the First Affiliated Hospital of Sun Yat-sen University Guangzhou Guangdong 510080 China

Background The relationship between symptom elimination and normalization of esophageal acid level of gastroesophageal reflux disease （GERD） on proton-pump inhibitor （PPI） therapy has been questioned. This study aimed to evaluate the relationship between symptom response and gastro-esophageal acidity control in Chinese patients with GERD on esomeprazole therapy, and to assess the role of 24-hour esophageal pH-metry after therapy in GERD *** GERD patients with typical reflux symptoms were enrolled and received esomeprazole 40 mg once daily for 4 weeks. Patients with positive baseline 24-hour esophageal pH-metry were divided into two groups depending on an additional dual-channel 24-hour pH-metry after treatment. The pH- group achieved normalization of esophageal pH level whereas the pH＋ group did *** Of the 80 patients studied, 76 had abnormal baseline esophageal pH levels. Of these, 90% （52/58） of symptom-free patients and 67% （12/18） of symptom-persistent patients achieved esophageal pH normalization after therapy （P=0.030）. The mean post-therapy gastric nocturnal percent time of pH 〈4.0 was significantly higher in pH＋group than that in pH- group （P 〈0.001） after therapy. The multivariate regression analysis identified hiatus hernia （P〈0.001） and persistent reflux symptom （P=0.004） were two independent factors predicting the low post-therapy esophageal pH *** Symptom elimination is not always accompanied by esophageal pH normalization, and vice *** pH-metry is recommended for GERD patients with hiatus hernia or with persistent reflux symptoms after PPI therapy.

关键词： gastroesophageal reflux esomeprazole symptom response esophageal pH level