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Piling up multidecker pyrgos[n]cages as antibacterial materials

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Science China Materials 2025年第1期68卷 314-316页

作者： Miguel A.Liuzzi-Vaamonde Jackson b.Lancaster Samantha A.Mason Yuanning Feng Department of Chemistry and biochemistry The University of OklahomaOklahoma 73019United States

The development of antibiotics is regarded as one of the most significant scientific advances in modern medicine. before the commercialization of antibiotics, infectious diseases were catastrophic throughout history [1]. Penicillin was used to treat serious infections in the 1940s, but unfortunately, with the introduction of antibiotics came the emergence of antibiotic resistance [2,3]. Evolved and adapted methicillin-resistant Staphylococcus aureus (MRSA) strains are presently impacting community and healthcare systems across the globe [4].

关键词： diseases adapted antibiotics

Physiological and ultralstructural changes of Chlorella sp. induced by UV-b radiation

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Progress in Natural Science:Materials International 2005年第8期15卷 678-683页

作者： YU Juan1, TANG Xuexi1*, ZHANG Peiyu 1,2, TIAN Jiyuan1 and DONG Shuanglin1(1. Division of Life Science and Technology, Ocean University of China, Qingdao 266003, China 2. College of Life Sciences, Qufu Normal University, Qufu 2731653, China) Division of Life Science and Technology Ocean University of China Qingdao 266003 China College of Life Sciences Qufu Normal University Qufu 2731653 China

In order to investigate the mechanisms of enhanced UV-b radiation on algae, the effects of UV-b radiation on the physiological and ultrastructural changes of Chlorella sp. were examined. The results showed that UV-b radiation could inhibit the growth and photosynthesis of microalgae. UV-b radiation at lower doses increased the photosynthetic pigment (chlorophyll a (Chla) and carotenoid (Car)) contents, while at higher doses of UV-b radiation Chla and Car contents were decreased. The ultrastructure of Chlorella sp. without exposure to UV-b showed that the thylakoid lamellae were clear and regular, the stroma of its chloroplast was apparent and clear. The globules with photosynthetic pigments and the cristae of mitochondria were clearly seen. After exposure to UV-b radiation at dose of 2.88 kJ/m2, the thylakoid lamellae of Chlorella sp. were lost and dissolved, the globules which contained photosynthetic pigments in chloroplast were bleached; some mitochondria cristae were dissolved; slight plasmolysis was found in some Chlorella sp. cells. After exposure to 5.76 kJ/m2 UV-b radiation, the thylakoid was in disarray and disintegration, plasmolysis was found in most cells, and the cell wall was broken and began to fall out. Many blank areas were observed in cells, mitochondria were seriously deformed and most of the mitochondria cristae were dissolved. Also, globules containing photosynthetic pigments in chloroplast were bleached and some empty globules were found in chloroplast. Therefore, UV-b radiation could damage cell structure of Chlorella sp., and this damage increased with the dose of UV-b radiation they exposed to.

关键词： UV-b radiation physiological changes ultrastructure Chlorella sp.

Identification of Nuclear Factor-κb Responsive Element within the Neuronal Nitric Oxide Synthase Exon If-specific Promoter

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Acta biochimica et biophysica Sinica 2007年第4期39卷 247-254页

作者： Yinghui LI~1 Guangyu LI~2 Chunyi LI~1 Yanyan ZHAO~1* 1 Department of Medical Genetics,China Medical University,Shenyang 110001 China 2 Department of Neurosurgery,First Affiliated Hospital,China Medical University,Shenyang 110001,China Department of Medical Genetics China Medical UniversityShenyang 110001 China Department of Neurosurgery First Affiliated Hospital China Medical UniversityShenyang 110001 China

Transcriptional regulation of the neuronal nitric oxide synthase gene(nNOS)is particularlycomplex as 12 distinct transcripts derived from different first exons are expressed in a tissue- and cell-specific *** exon 1f mRNA is relatively highly expressed in nervous system and relies upon exon1f-specific promoter *** conventional and real-time reverse transcription-polymerase chain reaction,we found exon 1f mRNA was the major transcript of the nNOS gene in human neuroblastoma *** analyzed a 1090 bp fragment of 1f promoter by TRANSFAC-TESS and Match softwares andluciferase assay,and found an important positive transcriptional regulation region that contained a putativenuclear factor(NF)-κb binding ***,using electrophoresis mobility shift and chromatinimmunoprecipitation assays,we identified this site to be the NF-κb responsive element,a crucial positiveregulator in the activation of the nNOS 1f *** together,our study identified an NF-κb responsiveelement within nNOS 1f promoter and showed that it plays an important role in the transactivation of nNOS1f mRNA,the major transcript of nNOS in SK-N-SH cells.

关键词： nNOS NF-kb transactivation nervous system

THEORETICAL AND NUMERICAL STUDY OF THE bLOW UP IN A NONLINEAR VISCOELASTIC PRObLEM WITH VARIAbLE-EXPONENT AND ARbITRARY POSITIVE ENERGY

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Acta Mathematica Scientia 2022年第1期42卷 141-154页

作者： Ala A.TALAHMEH Salim A.messaoudi Mohamed ALAHYANE Mathematics Birzeit UniversityWest BankPalestine Mathematics University of SharjahP.O.Box 27272SharjahUAE Department of Mathematics RISEUniversity of SharjahP.O.Box 27272SharjahUAE

In this paper,we consider the following nonlinear viscoelastic wave equation with variable exponents:utt-△u+∫_(0)^(t)g(t-τ)△u(x,τ)dτ+μut=|u|^(p(x)-2)-u,whereμis a nonnegative constant and the exponent of nonlinearity p(·)and g are given *** arbitrary positive initial energy and specific conditions on the relaxation function g,we prove a finite-time blow-up *** also give some numerical applications to illustrate our theoretical results.

关键词： nonlinear damping blow up finite time variable nonlinearity arbitrary positive energy

Hsp90 inhibition results in autophagy-mediated proteasome-independent degradation of Iκb kinase(IKK)

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Cell Research 2006年第11期16卷 895-901页

作者： Guoliang Qing~1 Pengrong Yan~1 Gutian Xiao ~1Department of Cell biology and Neuroscience,Rutgers,The State University of New Jersey,604 Allison Road,Piscataway,08854,USA Department of Cell biology and Neuroscience Rutgers The State University of New Jersey Piscataway USA

Autophagic and proteasomal proteolysis are two major pathways for degradation of cellular *** suggest that autophagy is responsible for the nonselective bulk degradation of long-lived proteins and organelleswhile the proteasome specifically degrades short-lived proteins including misfolded proteins caused by the absence ofHsp90 ***,we show that the Iκb kinase(IKK),an essential activator of NF-κb,is selectively degraded byautophagy when Hsp90 is inhibited by geldanamycin(GA),a specific Hsp90 inhibitor showing highly effective *** find that in this case inactivation of ubiquitination or proteasome fails to block IKK ***,inhibition of autophagy by an autophagy inhibitor or knockout of Atg5,a key component of the autophagy pathway,significantly rescues IKK from GA-induced *** findings provide the first evidence that an Hsp90 clientmay be degraded by a mechanism different from the proteasome pathway and establish a molecular link among Hsp90,NF-κb and autophagy

关键词： autophagy geldanamycin Hsp90 Iκb kinase NF-κb proteasome selective degradation therapy

A GENERAL DECAY AND OPTIMAL DECAY RESULT IN A HEAT SYSTEM WITH A VISCOELASTIC TERM

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Acta Mathematica Scientia 2019年第2期39卷 618-626页

作者： Abderrahmane YOUKANA Salim A.messaoudi Aissa GUESMIA Department of Mathematics University of Batna Department of Mathematics and Statistics KFUPM Elie Cartan Institute of Lorraine Universite de Lorraine Department of Mathematics and Statistics King Fahd University of Petroleum and Minerals

We consider a quasilinear heat system in the presence of an integral term and establish a general and optimal decay result from which improves and generalizes several stability results in the literature.

关键词： heat equation viscoelastic general decay optimal

Hepatitis b virus X protein modulates the apoptosis of hepatoma cell line induced by TRAIL

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Science China(Life Sciences) 2005年第3期48卷 277-286页

作者： LIANG Xiaohong 1 , SUN Wensheng 1 , GAO Lifen 1 , MA Chunhong 1 , HAN Lihui 1 & CHEN Youhai 2 1. Institute of Immunology, Medical School of Shandong University, Jinan 250012, China 2. Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia PA19104, USA 1. Institute of Immunology Medical School of Shandong University 250012 Jinan China 2. Department of Pathology and Laboratory Medicine University of Pennsylvania 19104 Philadelphia PA USA

The purpose of this study is to observe the effects of Hbx on the apoptosis of hepatoma cells induced by TNF-related apoptosis-inducing ligand (TRAIL) and to study prelimi- nary molecular mechanisms for its effects. In order to set up a model in vitro, bEL7402-Hbx cell line, stably expressing Hbx mRNA, was established by stable transfection of pcDNA-Hbx, which contains Hbx gene, into hepatoma cell line bEL7402. Control cell line bEL7402-cDNA3, stably transfected with pcDNA3, was set up simultaneously as a control. Trypan blue exclusion test, caspase 3 activity detection and TUNEL assay were performed to detect the apoptosis of bEL7402, bEL7402-cDNA3, bEL7402-Hbx induced by TRAIL. The expression of TRAIL recep- tors in three groups was analyzed by Flow cytometry. In addition, phosphorothioated antisense oligonucleotide against the translation initial region of Hbx gene (PS-asODNs/Hbx) was used to block the expression of Hbx in HepG2.2.15 cells and to further confirm the effects of Hbx on TRAIL-induced apoptosis. Trypan blue exclusion test indicated that TRAIL had a dose-dependent cytotoxicity on bEL7402, bEL7402-cDNA3 and bEL7402-Hbx cells. Under treatment of the same concentration of TRAIL, bEL7402-Hbx had a higher apoptosis rate and a higher level of Caspase 3 activation than bEL7402 and bEL7402-cDNA3. TUENL assay showed that the apoptosis rate of bEL7402-Hbx induced by 10 μg/L TRAIL was 41.4%±7.2%, signifi- cantly higher than that of bEL7402 and bEL7402-cDNA3 cells. blockade of Hbx expression in Hep G2.2.15 cells partly inhibited the apoptosis induced by TRAIL. The introduction or blockade of Hbx did not change the expression pattern of TRAIL receptors. The present study firstly con- firms the effects of Hbx on TRAIL- induced apoptosis from two different points and it is not re- lated with the expression level of TRAIL receptors. This would be useful to further clarify the roles of imbalanced apoptosis in pathogenesis of Hepatitis b and related hepatocellular carc

关键词： apoptosis, TRAIL, hepatitis b virus X protein, phosphorothioated antisense oligonucleotide.

Mutational Analysis of the Absolutely Conserved b8Gly: Consequence on Foldability and Activity of Insulin

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Acta biochimica et biophysica Sinica 2005年第10期37卷 673-679页

作者： Zhan-Yun GUO~1 Zhou ZHANG~1 Xiao-Yuan JIA~1 Yue-Hua TANG~(1,2) You-Min FENG~(1,2*) 1 Key Laboratory of Proteontics,Institute of biochemistry,and Cell biology,Shanghai Institutes for biological Sciences.Chinese Academy of Sciences,Shanghai 200031.China 2 Instutute of biochemistry,Zhejiang Sci-Tech University,Hangzhou 310018,China Key Laboratory of Proteomics Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China Institute of biochemistry Zhejiang Sci-Tech UniversityHangzhou 310018 China

b8Gly is absolutely conserved in insulins during ***,its correspondingposition is always occupied by a Gly residue in other members of insulin *** work showedthat Ala replacement of bSGly significantly decreased both the activity and the foldability of *** effects of substitution are complicated,and different replacements sometimes cause significantly *** analyze the effects of b8 replacement by different amino acids,three new insulin/single-chaininsulin mutants with bSGly replaced by Ser,Thr or Leu were prepared by protein engineering,and both theirfoldability and activity were *** general,replacement of bSGly by other amino acids causes significantdetriment to the foldability of single-chain insulin:the conformations of the three b8 mutants are essentiallydifferent from that of wild-type molecules as revealed by circular dichroism;their disulfide stabilities inredox buffer are significantly decreased:their in vitro refolding efficiencies are decreased approximatelytwo folds;the structural stabilities of the mutants with Ser or Thr substitution are decreased significantly,while Leu substitution has little effect as measured by equilibrium guanidine *** far as biologicalactivity is *** replacement of b8Gly has only a moderate effect:its insulin receptor-bindingactivity is 23% of native *** Thr or Leu replacement produces significant detriment:the receptor-binding potencies of the two mutants are less than 0.2% of native *** present results suggest thatGly is likely the only applicable natural amino acid for the b8 position of insulin where both foldability andactivity are concerned.

关键词： insulin foldability activity disulfide stability

ECHOS OF THE STEINER-LEHMUS EQUAL bISECTORSSTHEOREM

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Acta Mathematica Scientia 2025年第1期45卷 257-263页

作者： Christoph bÖRGERS Eric L.GRINbERG Mehmet ORHON Junhao SHEN Department of Mathematics Tufts UniversityMedfordMA02155USA Department of Mathematics University of Massachusetts BostonBostonMA02125USA Department of Mathematics&Statistics University of New HampshireDurhamNH03824USA

The Steiner-Lehmus equal bisectors theorem originated in the mid 19th *** its age,it would have been accessible to Euclid and his *** theorem remains evergreen,with new proofs continuing to appear *** theorem has fostered discussion about the nature of proof itself,direct and *** we continue the momentum by providing a trigonometric proof,relatively short,based on an analytic estimate that leverages algebraic trigonometric *** proofs of the theorem exist in the *** of these contain key ideas that already appeared in ***’1850 proofs,not always with *** the aim of increasing awareness of and making more accessible Lehmus’proofs,we provide an annotated *** conclude with remarks on different proofs and relations among them.

关键词： Steiner-Lehmus theorem equal bisectors