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An Improved K-Means Algorithm Based on Initial Clustering Center Optimization

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ZTE Communications 2017年第B12期15卷 43-46页

作者： LI Taihao NAREN Tuya ZHOU Jianshe REN Fuji LIU Shupeng Beijing Advanced Innovation Center for Imaging Technology Capital Normal UniversityBeijing 100048China Flatley Discovery Lab Boston 02129USA Department of Information Science&Intelligent Systems University of TokushimaTokushima 7708506Japan School of Communication and Information Engineering Shanghai UniversityShanghai 200072China

The K-means algorithm is widely known for its simplicity and fastness in text clustering.However,the selection of the initial clus?tering center with the traditional K-means algorithm is some random,and therefore,the fluctuations and instability of the clustering results are strongly affected by the initial clustering center.This paper proposed an algorithm to select the initial clustering center to eliminate the uncertainty of central point selection.The experiment results show that the improved K-means clustering algorithm is superior to the traditional algorithm.

关键词： clustering K-means algorithm initial clustering center

Development of sterically hindered SPOs and enantioselective Ni-Al bimetallic catalyzed C-H cyclization of 4-oxoquinazolines with tethered alkenes

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Chinese Chemical Letters 2023年第6期34卷 366-370页

作者： Yaqi Zhang Qiang Ni Bendu Pan Long Jiang Liqin Qiu School of Chemistry Guangdong Key Lab of Chiral Molecules and Drug DiscoverySun Yat-sen UniversityGuangzhou 510006China Instrumental Analysis and Research Centre Sun Yat-sen UniversityGuangzhou 510275China

The Ni-Al bimetallic catalysis of intramolecular enantioselective and regioselective C-H cyclization of4-oxoquinazolines with tethered alkenes has been successfully developed.Some new secondary phosphine oxides(SPOs)with large steric hindrance(SPO6-11)were designed and successfully synthesized from readily available chiral amines or amino acids.The developed chiral SPOs as ligands or preligands demonstrate much higher efficiency in the asymmetric catalytic reactions than the reported traditional ones.A new class of chiral tricyclic pyrroloquinazolinones were obtained in up to 95%yield and 99%ee.

关键词： Ni-Al bimetallic catalysis Secondary phosphine oxides C-H cyclization Asymmetric catalysis 4-Oxoquinazolines

Synthesis and in vitro antitumor activity of novel diaryl urea derivatives

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Chinese Chemical Letters 2013年第5期24卷 386-388页

作者： Yan-Fang Zhao Zi-Jian Liu Xin Zhai Dan-Dan Ge Qiang Huang Ping Gong Key lab of New Drugs Design and discovery of Liaoning Province School of Pharmaceutical EngineeringShenyang Pharmaceutical University

A series of novel diaryl ureas containing 4-[（2-amino-6-trifluromethyl）pyrimidine-4-yl]piperazine-l-yl group were synthesized and evaluated for their cytotoxic activities in a panel of human cancer cell lines. Compared with the reference drug Sorafenib,some compounds showed more potent and a broader spectrum of anti-cancer activities.Among them,compound 2p demonstrated significant inhibitory activities against MDA-MB-231,HT-29 and MCF-7 cell lines with IC_（50） values of 0.016,0.63,0.001μmol/L, respectively.

关键词： Diaryl ureas Synthesis Antitumor activity in vitro

Synthetic Study on Polyhydroxyestrogens Modeled for Inagami-Tamura Endogenous Digitalis-like Factor and Their Activity

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复旦学报（自然科学版） 2007年第5期46卷 603-604页

作者： Masayuki Sakakibara lab of Pharmaceutical Resource discovery Dalian Institute of Chemistry and Physics

1 Results Mammalian possess receptors for digitalis,cardiac glycosides,derived from plants.As one of the results from studies on a real endogenous ligand for the receptors,so called an endogenous digitalis-like factor (EDF) or substance (EDS),Inagami and Tamura isolated a promising candidate possessing a molecular weight,336.We elucidated several possible structures (Fig.1) for the factor and synthesized several modeled compounds,some of which exhibited remarkable constriction at higher concentrations t...

关键词： inagami-tamura endogenous digitalis-like factor (EDF) activity

Potential applications of lactic acid bacteria and bacteriocins in antimycobacterial therapy

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Asian Pacific Journal of Tropical Medicine 2018年第8期11卷 453-459页

作者： Anbarasu Sivaraj Revathy Sundar Radhakrishnan Manikkam Krupakar Parthasarathy Uma Rani Vanaja Kumar Centre for Drug discovery and Development Sathyabama Institute of Science and Technology

Tuberculosis(TB) is a communicable disease caused by Mycobacterium tuberculosis(M. tuberculosis). WHO estimated that 10.4 million new(incident) TB cases worldwide in year 2016. The increased prevalence of drug resistant strains and side effects associated with the current anti-tubercular drugs make the treatment options more complicated. Hence, there are necessities to identify new drug candidates to fight against various sub-populations of M. tuberculosis with less or no toxicity/side effects and shorter treatment duration. Bacteriocins produced by lactic acid bacteria(lab) attract attention of researchers because of its "Generally recognized as safe" status. lab and its bacteriocins possess an effective antimicrobial activity against various bacteria and fungi. Interestingly bacteriocins such as nisin and lacticin 3147 have shown antimycobacterial activity in vitro. As probiotics, lab plays a vital role in promoting various health benefits including ability to modulate immune response against various infectious diseases. lab and its metabolic products activate immune system and thereby limiting the M. tuberculosis pathogenesis. The protein and peptide engineering techniques paved the ways to obtain hybrid bacteriocin derivatives from the known peptide sequence of existing bacteriocin. In this review, we focus on the antimycobacterial property and immunomodulatory role of lab and its metabolic products. Techniques for large scale synthesis of potential bacteriocin with multifunctional activity and enhanced stability are also discussed.

关键词： Bacteriocin Lactic acid bacteria Antimycobacterial peptides Tuberculosis Immunomodulation Hybrid bacteriocin

Unraveling the relationship between histone methylation and nonalcoholic fatty liver disease

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WORLD JOURNAL OF HEPATOLOGY 2024年第5期16卷 703-715页

作者： Xu, Li Fan, Yu-Hong Zhang, Xiao-Jing Bai, Lan Gannan Med Univ State Key Lab New Targets Discovery & Drug Dev Maj Huangjin Campus Ganzhou 341000 Jiangxi Peoples R China Gannan Med Univ Gannan Innovat & Translat Med Res Inst Huangjin Campus Ganzhou 341000 Jiangxi Peoples R China Gannan Med Univ Key Lab Prevent & Treatment Cardiovasc & Cerebrova Minist Educ Huangjin Campus Ganzhou 341000 Jiangxi Peoples R China Wuhan Univ Sch Basic Med Sci Wuhan 430060 Peoples R China Gannan Med Univ Gannan Innovat & Translat Med Res Inst State Key Lab New Targets Discovery & Drug Dev Maj Ganzhou 341000 Peoples R China

Non-alcoholic fatty liver disease (NAFLD) poses a significant health challenge in modern societies due to shifts in lifestyle and dietary habits. Its complexity stems from genetic predisposition, environmental influences, and metabolic factors. Epigenetic processes govern various cellular functions such as transcription, chromatin structure, and cell division. In NAFLD, these epigenetic tendencies, especially the process of histone methylation, are intricately intertwined with fat accumulation in the liver. Histone methylation is regulated by different enzymes like methyltransferases and demethylases and influences the expression of genes related to adipogenesis. While early-stage NAFLD is reversible, its progression to severe stages becomes almost irreversible. Therefore, early detection and intervention in NAFLD are crucial, and understanding the precise role of histone methylation in the early stages of NAFLD could be vital in halting or potentially reversing the progression of this disease.

关键词： Non-alcoholic fatty liver disease Mechanism Histone methylation Methyltransferases Demethytrasferases Epigenetic modification Adipogenesis C/EBP-ALPHA EXPRESSION DEMETHYLASE 1 PROMOTES HEPATOCELLULAR-CARCINOMA EPIGENETIC THERAPY OXIDATIVE STRESS PPAR-GAMMA METHYLTRANSFERASE ROLES GENE THERMOGENESIS

A chitosan-mediated inhalable nanovaccine against SARS-CoV-2

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Nano Research 2022年第5期15卷 4191-4200页

作者： Shao-Hua Zhuo Jun-Jun Wu Lang Zhao Wen-Hao Li Yu-Fen Zhao Yan-Mei Li Key lab of Bioorganic Phosphorus Chemistry&Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084China Beijing Institute for Brain Disorders Beijing 100069China Center for Synthetic and Systems Biology Tsinghua UniversityBeijing 100084China Institute of Drug discovery Technology Ningbo UniversityNingbo 315221China

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),with several antigenic variants,has grown into a global challenge,and the rapid establishment of an immune barrier is crucial to achieving long-term control of the virus.This has led to a great demand for easy preparation and scalable vaccines,especially in low-income countries.Here,we present an inhalable nanovaccine comprising chitosan and SARS-CoV-2 spike protein.The chitosan-mediated nanovaccine enabled a strong spike-specific antibody immune response and augmented local mucosal immunity in bronchoalveolar lavage and lungs,which might be capable of protecting the host from infection without systemic toxicity.In addition,the enhanced adaptive immunity stimulated by chitosan showed potential protection against SARS-CoV-2.Furthermore,inhalation of the nanovaccine induced a comparable antibody response compared to intramuscular injection.This inhalable nanovaccine against SARS-CoV-2 offers a convenient and compliant strategy to reduce the use of needles and the need for medical staff.

关键词： severe acute respiratory syndrome coronavirus 2(SASR-CoV-2) inhalation nanovaccine chitosan

Identifi cation of egg protein-derived peptides as xanthine oxidase inhibitors:virtual hydrolysis,molecular docking,and in vitro activity evaluation

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Food Science and Human Wellness 2022年第6期11卷 1591-1597页

作者： Zhipeng Yu Yaxin Cao Ruotong Kan Huizhuo Ji Wenzhu Zhao Sijia Wu Jingbo Liu David Shiuan School of Food Science and Engineering Hainan UniversityHaikou 570228China College of Food Science and Engineering Bohai UniversityJinzhou 121013China lab of Nutrition and Functional Food Jilin UniversityChangchun 130062China Institute of Drug discovery Technology Ningbo UniversityNingbo 315211China

The purpose of this study was to screen the xanthine oxidase(XO)inhibitory peptides from egg white proteins through virtual hydrolysis,in vitro activity validation,and molecular docking.The results demonstrated that tripeptide EEK from ovalbumin exhibited potent XO inhibitory activity with an IC50 value of 141μmol/L.The molecular docking results showed that tripeptide EEK bound with the active center of XO via 3 carbon hydrogen bond interactions,2 salt bridges,5 conventional hydrogen bond interactions,and 4 attractive charge interactions.The residues Glu802,Phe1009,and Arg880 may play key roles in the XO catalytic reaction.Especially,the key intermolecular forces of inhibiting XO activity may be special type of hydrogen bonds including carbon hydrogen bond interactions and attraction charge interactions.The novel tripeptide EEK is potential candidates for controlling hyperuricemia.

关键词： Egg protein-derived peptides Hyperuricemia Inhibitor mechanism Molecular docking Xanthine oxidase

Rationally designed amyloid inhibitors based on amyloid-related structural studies

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Chinese Chemical Letters 2023年第2期34卷 7-17页

作者： Jinjian Hu Yufen Zhao Yanmei Li Department of Chemistry Key Lab of Bioorganic Phosphorus Chemistry&Chemical BiologyTsinghua UniversityBeijing 100084China Beijing Institute for Brain Disorders Beijing 100069China Center for Synthetic and Systems Biology Tsinghua UniversityBeijing 100084China Institute of Drug discovery Technology Ningbo UniversityNingbo 315221China

Amyloid proteins correlate with a series of degenerative diseases. Targeting amyloid aggregation has remained a hot topic in therapeutic studies. Numerous inhibitors have been developed, but very few have been approved for marketing. Meanwhile, the growing knowledge of amyloid structural characteristics provides a basis for the rational design of inhibitors. Here we introduce the high-resolution structural findings of amyloid fibrils in recent years and discuss the reported strategies toward rationally designed inhibitors based on amyloid-related structural studies.

关键词： Amyloid Amyloid structure Degenerative disease Amyloid inhibitor Rational design