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Journal of Oceanology and Limnology 2024年第6期42卷 1991-1997页

作者： Shuangling TAN Yang LIU Haonan FU Yutong XUE Fangjian FENG Jinling LI Xiaojun YAN Sitong WU Shan HE Lijian DING Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center Ningbo UniversityNingbo 315211China Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University Taizhou 318053China School of Pharmaceutical Sciences Zhejiang University of TechnologyHangzhou 310014China Ningbo Institute of Marine Medicine Peking UniversityNingbo 315800China

Marine natural products offer a promising source in the development of new antibiotic *** previously undescribed compounds,including one sulfur-bearing alkaloid named quinosumycin(1)along with one chromone derivative namely chromycone(2),were discovered from an ethyl acetate(EtOAc)extract of marine Streptomyces diastaticus NBU2966 through a bioactivity-guided isolation prioritized for antimicrobial *** analysis of nuclear magnetic resonance(NMR)spectroscopy,high resolution electrospray ionization mass spectroscopy(HRESIMS)data,and electronic circular dichroism(ECD)calculations enabled the elucidation of their structures and the determination of their absolute ***(1)is the first heterodimer scaffold incorporating quinolinone and quinazolinone motifs coupled by a thioether ***,Compound 1 exhibited a relatively selective growth inhibition against methicillin-resistant Staphylococcus aureus(MRSA)with the minimal inhibitory concentration(MIC)value of 8μg/mL.

关键词： marine natural product marine Streptomyces thioether alkaloid heterodimer anti-methicillinresistant Staphylococcus aureus(anti-MRSA)

Synthesis and photophysical properties of porphyrin-phthalocyanine heterodimer linked by piperazine

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Chinese Journal of Chemistry 1998年第2期16卷 97-108页

作者：李希友周庆复田宏健许慧君 Institute of Photographic Chemistry Chinese Academy of SciencesBeijing 100101China

A porphyrin-phthalocyanine heterodimer linked by piperazine has been synthesized and characterized by spectroscopic methods. UV-visible absorption spectra indicated the presence of weak intramolecular interaction between the two chromophores. Selective excitation of the porphyrin moiety leads to energy transfer process to the phthalocyanine subunit. Furthermore, on the bases of the solvent-dependent fluorescence data, a competing electron transfer reaction is shown to occur in this heterodimer. The efficiency of both photophysical processes depends strongly on solvent polarity and is related to the separation distance of the two chromophores and their relative orientation. The value of ΔG obtained using the Rehm-Weller equation clearly indicates that the heterodimer exists preferably in the “boat form” upon excitation in good agreement with the experimental results of co-occurence of energy and electron transfer process observed for the heterodimer.

关键词： Porphyrin phthalocyanine heterodimer piperazine photophysical property

Structure of Protonated heterodimer of Proline and Phenylalanine:Revealed by Infrared Multiphoton Dissociation Spectroscopy and Theoretical Calculations

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Chinese Journal of Chemical Physics 2020年第5期33卷 590-594,I0029-I0038,I0079页

作者： Juan Ren Xian-yi Zhang Xiang-lei Kong State Key Laboratory of Elemento-organic Chemistry College of ChemistryNankai UniversityTianjin 300071China School of Physics and Electronic Information Anhui Normal UniversityAnhui Normal UniversityWuhu 241000China Collaborative Innovation Center of Chemical Science and Engineering Nankai UniversityTianjin 300071China

The infrared multiphoton dissociation(IRMPD)spectrum of the protonated heterodimer of Pro Phe H+,in the range of 2700-3700 cm^-1,has been obtained with a Fourier-transform ion cyclotron mass spectrometer combined with an IR OPO *** experimental spectrum shows one peak at 3565 cm^-1 corresponding to the free carboxyl O-H stretching vibration,and two broad peaks centered at 2935 and 3195 cm^-*** calculations were performed on the level of M062 X/6-311++G(d,p).Results show that the most stable isomer is characterized by a charge-solvated structure in which the proton is bound to the unit of *** predicted spectrum is in good agreement with the experimental one,although the coexistence of salt-bridged structures cannot be entirely excluded.

关键词： Infrared multiphoton dissociation spectroscopy Mass spectrometry heterodimer Amino acids

Self-assembly of Hydrazide-based heterodimers Driven by Hydrogen Bonding and Donor-Acceptor Interaction

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Chinese Journal of Chemistry 2006年第9期24卷 1200-1208页

作者：冯代军王鹏李小强黎占亭 Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

A new series of hydrogen bonding-driven heterodimers have been self-assembled in chloroform from hydrazide-based monomers. Additional intermolecular donor-acceptor interaction between the electron-rich bis（p-phenylene）-34-crown-10 unit and the electron-deficient naphthalene diimide unit has been utilized to increase the stability of the dimmers, and pronounced cooperativity of the two discrete non-covalent forces to stabilize the dimer has been revealed by the quantitative ^1H （2D） NMR and UV-Vis experiments.

关键词： hydrazide heterodimer self-assembly hydrogen bonding donor-acceptor interaction

Src heterodimerically activates Lyn or Fyn to serve as targets for the diagnosis and treatment of esophageal squamous cell carcinoma

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Science China(Life Sciences) 2023年第6期66卷 1245-1263页

作者： Jing Zhang Di Zhao Lingyuan Zhang Yuanfan Xiao Qingnan Wu Yan Wang Jie Chen Qimin Zhan Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Laboratory of Molecular OncologyPeking University Cancer Hospital&InstituteBeijing100142China Peking University International Cancer Institute Peking UniversityBeijing100191China Research Unit of Molecular Cancer Research Chinese Academy of Medical SciencesBeijing100142China Institute of Cancer Research Shenzhen Bay LaboratoryShenzhen518107China

Although Src is one of the oldest and most investigated oncoproteins,its function in tumor malignancy remains to be defined *** this study,we demonstrated that the inhibition of Src activity by ponatinib effectively suppressed several malignant phenotypes of esophageal squamous cell carcinoma(ESCC)both in vitro and in vivo,whereas it did not produce growthinhibitory effects on normal esophageal epithelial cells(NEECs).Importantly,we combined phosphoproteomics and several cellular and molecular biologic strategies to identify that Src interacted with the members of Src-family kinases(SFKs),such as Fyn or Lyn,to form *** interactions with Fyn and Lyn phosphorylated the tyrosine sites in SH2(Fyn Tyr^(185)or Lyn Tyr^(183))and kinase domains(Fyn Tyr^(420) or Lyn Tyr^(397)),which critically contributed to ESCC *** contrast,Src could not form heterodimers with Fyn or Lyn in *** used RNA sequencing to comprehensively demonstrate that the inhibition of Src activity effectively blocked several critical tumor-promoting pathways,such as JAK/STAT,mTOR,stemness-related,and metabolism-related *** of the real-time polymerase chain reaction(RT-PCR)assay confirmed that Lyn and Fyn were critical effectors for the Src-mediated expression of tumor growth or metastasis-related ***,results of the clinical ESCC samples showed that the hyperactivation of pSrc Tyr^(419),Fyn Tyr^(185) or Tyr^(420),and Lyn Tyr^(183)or Tyr^(397)could be biomarkers of ESCC *** study illustrates that Src/Fyn and Src/Lyn heterodimers serve as targets for the treatment of ESCC.

关键词： esophageal squamous cell carcinoma heterodimer Src-family kinase Src tyrosine phosphorylation

Carrier frequency of HLA-DQB1*02 allele in patients affected with celiac disease:A systematic review assessing the potential rationale of a targeted allelic genotyping as a first-line screening

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World Journal of Gastroenterology 2020年第12期26卷 1365-1381页

作者： Dimitri Poddighe Chiara Rebuffi Annalisa De Silvestri Cristina Capittini Department of Medicine School of MedicineNazarbayev UniversityNur-Sultan 010000Kazakhstan Grant Office and Scientific Documentation Center Fondazione IRCCS Policlinico San MatteoPavia 27100Italy Scientific Direction Clinical Epidemiology and Biometric UnitFondazione IRCCS Policlinico San MatteoPavia 27100Italy Department of Biology and Biotechnology"Lazzaro Spallanzani" University of PaviaPavia 27100Italy

BACKGROUND Celiac Disease(CD)is an immune-mediated disorder,in which the HLA immunogenetic background(DQ2 and DQ8 heterodimers)and environmental trigger(gluten)are well ***,both factors are necessary–but not sufficient–to develop ***,it is very likely that CD is underdiagnosed in both developing and developed countries,due to several aspects,including the fact that a lot of patients present mild and/or atypical symptoms,without the presence of any recognized risk ***,the possibility and feasibility of widened screening strategies to identify CD patients are *** To provide further evidence of the main epidemiological importance of HLADQB1*02 allele in the population of CD *** We performed a systematic search in PubMed,EMBASE,Cochrane,Web of Science and Scopus databases,in order to produce a systematic review assessing the carrier frequency of HLA-DQB1*02 allele in the celiac *** the PRISMA guidelines,we retrieved all the original articles describing CD patients’HLA-DQB1 genotype in such a way that could allow to assess the HLADQB1*02 carrier frequency among CD patients,along with the evidence of the appropriate diagnostic work-up to achieve a correct and final diagnosis of *** The final output of this systematic search in the medical literature consisted of 38 studies providing the appropriate HLA-DQB1 genotype information of the respective CD *** to this systematic review,including a pool of 4945 HLA-DQ genotyped CD patients,the HLA-DQB1*02 carrier frequency was 94.94%,meaning that only 5.06%of CD patients were completely lacking this allelic ***,if we consider only the studies whereby the prevalence of CD patients affected with type 1 diabetes mellitus was supposed or clearly established to be very low,the frequency of non-HLA-DQB1*02 carriers among CD patients dropped to 3.65%.CONCLUSION Such a high carrier frequency of the HLA-DQB1*02 allelic varian

关键词： Celiac disease Children HLA-DQB1*02 DQ2 heterodimer Screening Systematic review

Crystallographic Studies of Cephalosporin Acylase from Pseudomonas sp. Strain 130

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Tsinghua Science and Technology 2003年第4期8卷 395-401页

作者：丁怡姜卫红张淑平茅翔 Mark Bartlam 赵国平饶子和 Laboratory of Structural Biology and Laboratory of Protein Science of the Ministry of Education Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China

The cephalosporin acylases are a group of enzymes that hydrolyze cephalosporin C and/or glutaryl 7 aminocephalosporanic acid to produce 7 aminocephalosporanic acid. The cephalosporin acylase from Pseudomonas sp. strain 130 was crystallized in two different forms suitable for structural studies. A tetragonal crystal form diffracted to 0.24 nm belonged to the space group P4 12 12. There was one αβ heterodimer per asymmetric unit. A second crystal form diffracted to 0.21 nm belonged to the space group P2 1. There was four αβ heterodimers per asymmetric unit. The tetragonal crystal structure of CA 130 was determined using the multiwavelength anomalous diffraction method and the P2 1 crystal structure was then determined using the molecular replacement method. 

关键词： cephalosporin acylase crystallization selenomethionine (Se Met) multiwavelength anomalous diffraction (MAD) heterodimer heterotetramer

Abnormal DNA-PKcs and Ku 70/80 expression may promote malignant pathological processes in gastric carcinoma

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World Journal of Gastroenterology 2013年第40期19卷 6894-6901页

作者： Wei Li Chuan Xie Zhen Yang Jiang Chen Nong-Hua Lu Department of Gastroenterology the First Affiliated Hospital of Nanchang University

AIM:To determine the expression of the catalytic subunit of DNA-dependent protein kinase(DNA-PKcs)and the Ku70/Ku80 heterodimer(Ku 70/80)in gastric ***:Gastric biopsies were obtained from 146gastric carcinoma patients[Helicobacter pylori(***)-negative:89 and ***-positive:57]and 34from normal subjects(***-negative:16 and ***-positive:18)via surgery and endoscopic detection from April 2011 to August 2012 at the First Affiliated Hospital of Nanchang *** diagnosis and classification were made according to the criteria of the World Health Organization and the updated Sydney ***‘‘in-house’’rapid urease test and modified Giemsa staining were employed to detect *** *** expression of DNA-PKcs and the Ku 70/80protein was detected by ***:Overall,the positive rates of both DNA-PKcs and Ku 70/80 were significantly increased in gastric cancer(χ2=133.04,P<0.001 for DNA-PKcs andχ2=13.06,P<0.01 for Ku)compared with normal gastric *** was hardly any detectable expression of DNA-PKcs in normal gastric mucosa,and the positive rate of DNA-PKcs protein expression in patients with a normal gastric mucosa was 0%(0/34),whereas the rate in gastric cancer(GC)was 93.8%(137/146).The difference between the two groups was statistically ***,the positive rate of Ku 70/80 was79.4%(27/34)in normal gastric mucosa and 96.6%(141/146)in gastric *** DNA-PKcs protein level was significantly increased in gastric cancer(MannWhitney U=39.00,P<0.001),compared with normal gastric *** addition,there was a significant difference in the expression of Ku 70/80(Mann-Whitney U=1117.00,P<0.001)between gastric cancer and normal gastric *** was also a significant difference in Ku70/80 protein expression between GC patients with and without *** infection(P<0.05).Spearman analysis showed a negative correlation between tumor differentiation and DNA-PKcs expression(r=-0

关键词： Helicobacter pylori Catalytic subunit of the DNA-dependent protein kinase Ku70/Ku80 heterodimer Gastric carcinoma Immunohistochemistry

Germline Deletion of the Expression of a Human Bispecific Mucosal Immunoglobulin: Genetic Predisposition to Cancer and Communicable Diseases Predominantly among African-Americans

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Open Journal of Preventive Medicine 2021年第10期11卷 383-390页

作者： Padmanabhan Nair NonInvasive Technologies LLC Elkridge MD USA Department of International Health The Johns Hopkins Bloomberg School of Public Health Baltimore Maryland USA

In a previous report we had reported on the discovery of a novel bispecific immunoglobulin expressed by colonic epithelial cells as they transform into immunomimetic cells during exfoliation (Albaugh et al. (2020) Open Journal of Preventive Medicine, 10, 126-150). Colonic cells isolated from 0.5 gm aliquots of fresh stools (SCSR-10, Fecal Cell Isolation Kit, NonInvasive Technologies, Elkridge, MD) preserved at room temperature for up to one week, with viability of >85% were used to determine the number of cells expressing this novel bispecific immunoglobulin. Over the course of this period (18 years) we recognized that these cells opened the opportunity to investigate the expression of cell membrane biomarkers. As the applications grew, we introduced a new terminology, termed COPROCYTOBIOLOGY*. In this study, we surveyed a cohort of 58 free-living adults for the expression of the newly discovered bi-specific chimeric antibody. Almost all of the subjects showed a strong signal during flow-cytometric evaluation of their stool samples;averaging around 65%. However, two subjects exhibited a total loss of this signal and both these individuals were of African-American lineage (one male and one female). These cells upon culturing in vitro remained defective in contrast to the rest of the group where their progeny continued to generate the antibody. We propose that this signals the existence of a germ-line deletion of the gene for which a novel test (MEDISHIELD†) is suggested. This syndrome may be associated with a lack of response to prophylactic vaccines involving m-RNA.

关键词： Colon Epithelial Cells IgA/IgG Bi-Specific Immunoglobulin Oncolysis Anti-Infective Firewall heterodimer Gastrointestinal Progenitor Cells (GIP-C†)