21 results on '"Bei Zheng"'
Search Results
2. Photo-gated and self-powered three-dimensional DNA motors with boosted biostability for exceptionally precise and efficient tracing of intracellular survivin mRNA
- Author
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Hong-Wu Tang, Da Liu, Yu-Heng Liu, Jun-Xian Liu, Wen-Kai Fang, Bei Zheng, Cheng-Yu Li, and Jia-Ling Gao
- Subjects
Fluorescence-lifetime imaging microscopy ,Computer science ,Survivin ,Biomedical Engineering ,Biophysics ,Deoxyribozyme ,Metal Nanoparticles ,Nanotechnology ,02 engineering and technology ,Biosensing Techniques ,Tracing ,01 natural sciences ,chemistry.chemical_compound ,Electrochemistry ,RNA, Messenger ,Flexibility (engineering) ,010401 analytical chemistry ,Oxides ,General Medicine ,DNA ,DNA, Catalytic ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,MicroRNAs ,chemistry ,Manganese Compounds ,Gold ,0210 nano-technology ,Biosensor ,Intracellular ,Biotechnology - Abstract
Benefiting from the outstanding signal amplification effect and the admirable construction flexibility, the currently proposed DNA motors (particularly DNA walkers) based biosensing concepts have provided a forceful fluorescence imaging tool for intracellular detection. Even so, this promising sensing means is not only subject to poor controllability and prone to produce false signals but also requires exogenous powering forces owing to the common employment of DNAzyme. In response to these challenges, we are herein motivated to present some meaningful solving strategies. For one thing, the surfaces of gold nanoparticles are conducted with a photo-gated walking behavior by introducing a photocleave mode, under which the light-switchable DNA walkers are capable of being selectively activated via an external ultraviolet source to faultlessly prevent the sensing frame from being pre-initiated during cellular uptake and intracellular delivery. For another, the intracellular biothiols are consumed by MnO2 nanosheets to effectively avoid the competitions to Au-S bonds to eliminate potential false outputs and also self-supply sufficient cofactors (Mn2+) to actualize a self-powered operation pattern as well as facilitate the endocytosis process. Following these breakthroughs, a favorable analysis performance towards a model tumor biomarker (survivin mRNA) is endowed with the newly raised biosensor, whose sensitivity is low to pM level with a sound specificity for identifying single base mismatching. Moreover, the significantly improved autonomous three-dimensional DNA walkers can be used to determine and dynamically trace the targets in live cancer cells with an exceptional precise and efficient manner, commendably impelling the sensing ability of DNA motors in biological specimens.
- Published
- 2021
3. A boosting upconversion luminescent resonance energy transfer and biomimetic periodic chip integrated CRISPR/Cas12a biosensor for functional DNA regulated transduction of non-nucleic acid targets
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Yu-Heng Liu, Hong-Wu Tang, Ming-Qiu Zheng, Cheng-Yu Li, Jia-Ling Gao, Dai-Wen Pang, and Bei Zheng
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Nucleic acid quantitation ,Materials science ,Aptamer ,Biomedical Engineering ,Biophysics ,Deoxyribozyme ,Nanotechnology ,02 engineering and technology ,Biosensing Techniques ,01 natural sciences ,Genome editing ,Biomimetics ,Electrochemistry ,CRISPR ,Humans ,Clustered Regularly Interspaced Short Palindromic Repeats ,010401 analytical chemistry ,General Medicine ,DNA ,021001 nanoscience & nanotechnology ,Photon upconversion ,0104 chemical sciences ,Nucleic acid ,CRISPR-Cas Systems ,0210 nano-technology ,Biosensor ,Biotechnology - Abstract
Apart from gene editing capacity, the newly discovered CRISPR/Cas systems offer an exciting option for biosensing field because of their excellent target recognition accuracy. However, the currently constructed sensors are not only limited to nucleic acid analysis but also suffer from poor adaptability in complex samples and unsatisfying sensitivity. We herein introduce some advanced concepts to break through these bottlenecks. First, the sensing targets are extended by skillfully designing a functional DNA such as aptamer (for protein) and DNAzyme (for metal ion) to regulate the transduction of non-nucleic acid species and further activate the trans cleavage of CRISPR/Cas12a. Second, a boosting upconversion luminescent resonance energy is triggered by using a peculiar energy-confining notion, whereby the luminescence domain is intensively restricted in a very narrow space (~2.44 nm) and up to 92.9% of the green emission can be quenched by the approaching BHQ-1 modified reporters. Third, a bio-inspired periodic arrangement biomimetic chip (photonic crystal) is employed to selectively reflect the upconversion luminescence to achieve noteworthy signal enhancement (~35-fold). By utilizing very simple detection devices (a 980 nm portable laser and a smartphone), the CRISPR/Cas12a biosensor shows commendable sensitivity and specificity toward model targets (ATP and Na+, limits of detection are ~ 18 nM and ~0.37 μM, respectively). More importantly, the analysis of real complex samples demonstrate that the as-proposed platform can work as a powerful toolbox for monitoring the ATP fluctuation in single cell and point-of-care testing Na+ in human plasma, enabling a broad application prospect.
- Published
- 2020
4. A META-ANALYSIS OF ABNORMAL GLUCOSE METABOLISM IN FIRST-EPISODE DRUG-NAIVE SCHIZOPHRENIA
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Meiling Zhang, Wenjuan Yang, Shen Zeng, Lulu Zheng, Jingjing Li, Bingqing Liang, Bei Zheng, and Jun Zhu
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Blood Glucose ,medicine.medical_specialty ,Population ,Carbohydrate metabolism ,Gastroenterology ,03 medical and health sciences ,0302 clinical medicine ,Insulin resistance ,Internal medicine ,Diabetes mellitus ,medicine ,Humans ,Insulin ,Prediabetes ,education ,First episode ,education.field_of_study ,business.industry ,Type 2 Diabetes Mellitus ,General Medicine ,medicine.disease ,030227 psychiatry ,Psychiatry and Mental health ,Drug-naïve ,Glucose ,Diabetes Mellitus, Type 2 ,First-episode schizophrenia ,drug-naïve ,glucose metabolism ,Schizophrenia ,business ,medicine.drug - Abstract
Background: Patients with schizophrenia exhibit a higher mortality rate compared with the general population. This mortality has been attributed predominantly by the high risk of type 2 diabetes mellitus in the patients. We aimed to assess the inherent risk of glucose metabolism abnormalities in first-episode drug-naïve schizophrenia. Subjects and methods: We searched English database (PubMed, EMBASE, MEDLINE, Cochrane Library databases) and Chinese database (Wan Fang Data, CBM disc, VIP, and CNKI) from their inception until Jul 2018 for case-control studies examining glucose metabolism abnormalities. Measurements, such as fasting plasma glucose levels, fasting plasma insulin levels, insulin resistance and HbA1c levels in first episode antipsychotic-naive patients were used to test for prediabetes. Standardized/weighted mean differences and 95% confidence intervals were calculated and analyzed. Results: 19 studies (13 in English and 6 in Chinese) consisting of 1065 patients and 873 controls were included. Fasting plasma glucose levels (95% CI; 0.02 to 0.29; P=0.03), 2 h plasma glucose levels after an OGTT (95% CI; 0.63 to 1.2; P
- Published
- 2020
5. Bioinspired sensor chip for detection of miRNA-21 based on photonic crystals assisted cyclic enzymatic amplification method
- Author
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Qiong Li, Sihui Zhou, Ting Zhang, Hong-Wu Tang, and Bei Zheng
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Materials science ,Indoles ,Polymers ,Biomedical Engineering ,Biophysics ,02 engineering and technology ,Biosensing Techniques ,01 natural sciences ,Signal ,Limit of Detection ,Electrochemistry ,Humans ,Photonic crystal ,Oligonucleotide Array Sequence Analysis ,Detection limit ,Photons ,business.industry ,010401 analytical chemistry ,General Medicine ,021001 nanoscience & nanotechnology ,Chip ,Biocompatible material ,Periodic nanostructures ,0104 chemical sciences ,Nanostructures ,MicroRNAs ,Enzymatic amplification ,Optoelectronics ,0210 nano-technology ,business ,Sensitivity (electronics) ,Nucleic Acid Amplification Techniques ,Nanospheres ,Biotechnology - Abstract
Cancer, as the most invasive disease in the world, has led to an increasing amount of death year by year, so it is highly desired to develop a portable device to monitor the aberrant expression of biomarker in cancer patient. Here, we present a bio-photonic periodic nanostructures sensor chip assisted cyclic enzymatic amplification method to detect miRNA-21 with a detection limit of 55 fM. By employing biocompatible polydopamine nanospheres (PDANs) and DNaseⅠto construct an target-recycling amplification process on the photonic crystals, the output fluorescence signal can be strengthened selectively and short amplification time is needed. Benefiting from the synergy of the enhancement of photonic crystals and enzymatic cycle amplification, we realize high sensitivity detection of miRNA-21 with a detection range of 1 pM–10 nM and a detection limit of about four orders of magnitudes lower than the method employs no amplification, showing an expectable prospect in the early diagnosis of cancer.
- Published
- 2019
6. Core epitope analysis of 16 kDa allergen from tartary buckwheat
- Author
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Peng Chen, Lei Wang, Wei Shen, Haina Zhang, and Bei Zheng
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Signal peptide ,Mutant ,Dot blot ,Enzyme-Linked Immunosorbent Assay ,medicine.disease_cause ,Epitope ,Pichia ,Analytical Chemistry ,Pichia pastoris ,Epitopes ,Allergen ,medicine ,Amino Acid Sequence ,B cell ,biology ,Chemistry ,Circular Dichroism ,General Medicine ,Allergens ,biology.organism_classification ,Molecular biology ,Recombinant Proteins ,medicine.anatomical_structure ,Isoelectric point ,Mutagenesis, Site-Directed ,Food Science ,Fagopyrum - Abstract
Tartary buckwheat is widely accepted as its nutritional value. Some allergic reactions hinder its utilization. This research focused on evaluating the core epitope of 16 kDa allergen (Fag t 2) in tartary buckwheat. Six B- and seven T cell epitopes of Fag t 2 were predicted, and six B cell epitope-mutants were expressed in Pichia pastoris. Bioinformatics analysis and SDS-PAGE demonstrated that the molecular weight, isoelectric point and spatial structures of six mutant allergens were similar with Fag t 2, with the same signal peptide sequences and α-amylase inhibitor domain. There was no significant change in mutants' spatial conformation confirmed by Circular Dichroism. The position K132N and peptides at 108–117 and 132–141 were the core B- and T cell epitopes of Fag t 2 confirmed by competitive inhibition ELISA and dot blot. This result was of great significance on the study of allergen epitopes in prevention and treatment of hypersensitivity.
- Published
- 2019
7. Interim estimates of divergence date and vaccine strain match of human influenza A(H3N2) virus from systematic influenza surveillance (2010–2015) in Hangzhou, southeast of China
- Author
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Jun Li, Yu Kou, Zhi bei Zheng, Xu hui Yang, Xin fen Yu, Yin yan Zhou, and Hao qiu Wang
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Microbiology (medical) ,China ,Antigenic drift ,Human influenza ,viruses ,Hemagglutinin Glycoproteins, Influenza Virus ,Influenza A ,Vaccine match ,Biology ,Virus ,Serology ,Divergence ,lcsh:Infectious and parasitic diseases ,03 medical and health sciences ,0302 clinical medicine ,Vaccine strain ,Phylogenetics ,Influenza, Human ,Humans ,lcsh:RC109-216 ,030212 general & internal medicine ,Prospective Studies ,Phylogeny ,030304 developmental biology ,0303 health sciences ,Strain (biology) ,Influenza A Virus, H3N2 Subtype ,virus diseases ,Bayes Theorem ,General Medicine ,H3N2 ,Virology ,3. Good health ,Infectious Diseases ,Influenza Vaccines ,Population Surveillance ,Seasons - Abstract
Summary Objectives In the post-pandemic period 2010–2015, seasonal influenza A(H3N2) virus predominated in Hangzhou, southeast of China, with an increased activity and semi-annual seasons. This study utilized HA virus gene segment sequences to analyze the divergence date and vaccine strain match of human influenza A(H3N2) virus from systematic influenza surveillance in Hangzhou. Methods Virological and serological analyses of 124 representative A(H3N2) viruses from prospective studies of systematic surveillance samples were conducted to quantify the genetic and antigenic characteristics and their vaccine strain match. Results Bayesian phylogenetic inference showed that two separate subgroups 3C.3 and 3C.2 probably diverged from group 3C in early 2012 and then evolved into groups 3C.3a and 3C.2a, respectively, in the 2014/15 influenza season. Furthermore, high amino acid substitution rates of the HA1 subunit were found in A(H3N2) group 3C.2a variants, indicating that increased antigenic drift of A(H3N2) group 3C.2a virus is associated with a vaccine mismatch to the 2015/16 vaccine reference strain Switzerland/9715293/2013 (group 3C.3a). Conclusions A portion of the group 3C.2a isolates are not covered by the current A(H3N2) vaccine strain. These findings offer insights into the emergence of group 3C.2a variants with epidemic potential in the imminent influenza seasons.
- Published
- 2015
8. Optical Fiber Sensor Salt Dense On-Line Monitoring Research
- Author
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Hu Zhang, Hong Shen, Li Hui Wu, Bao Qiang Liu, Gao Liu, and Jin Bei Zheng
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Engineering ,Workstation ,business.industry ,Attenuation ,Humidity ,Insulator (electricity) ,General Medicine ,law.invention ,Luminous flux ,Support vector machine ,Fiber optic sensor ,law ,GSM services ,business ,Remote sensing - Abstract
To detect the pollution level of insulators in operation, based on light energy loss theory of medium optical wave guide and mathematical modeling of least squares supporting vector machine, by a lot of contrast tests, this paper designed and developed monitoring terminal of optical sensor. Collecting live temperature, humidity luminous flux attenuation etc. and sending the collected data to data monitoring centre through GSM data communication module, the workstation of data monitoring centre could calculate to get equivalent salt deposit density (ESDD) using mathematical model, so that insulators pollution level can be detected on-line automatically and continuously.
- Published
- 2013
9. Fluopsin C induces oncosis of human breast adenocarcinoma cells
- Author
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Min Cui, Shan-Shan Liu, Chang-you Jiang, Bei-bei Zheng, Rong Lu, Xia Li, Li-sha Ma, and Lin Li
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Programmed cell death ,Pathology ,medicine.medical_specialty ,Antineoplastic Agents ,Breast Neoplasms ,Adenocarcinoma ,Biology ,Hydroxylamines ,Flow cytometry ,chemistry.chemical_compound ,Cell Line, Tumor ,Lactate dehydrogenase ,medicine ,Humans ,Pharmacology (medical) ,MTT assay ,Viability assay ,Propidium iodide ,Cytotoxicity ,Pharmacology ,medicine.diagnostic_test ,Epithelial Cells ,General Medicine ,Molecular biology ,chemistry ,MCF-7 Cells ,Female ,Original Article ,Intracellular - Abstract
Fluopsin C, an antibiotic isolated from Pseudomonas jinanesis, has shown antitumor effects on several cancer cell lines. In the current study, the oncotic cell death induced by fluopsin C was investigated in human breast adenocarcinoma cells in vitro. Human breast adenocarcinoma cell lines MCF-7 and MD-MBA-231 were used. The cytotoxicity was evaluated using MTT assay. Time-lapse microscopy and transmission electron microscopy were used to observe the morphological changes. Cell membrane integrity was assessed with propidium iodide (PI) uptake and lactate dehydrogenase (LDH) assay. Flow cytometry was used to measure reactive oxygen species (ROS) level and mitochondrial membrane potential (Δψm). A multimode microplate reader was used to analyze the intracellular ATP level. The changes in cytoskeletal system were investigated with Western blotting and immunostaining. Fluopsin C (0.5-8 μmol/L) reduced the cell viability in dose- and time-dependent manners. Its IC50 values in MCF-7 and MD-MBA-231 cells at 24 h were 0.9 and 1.03 μmol/L, respectively. Fluopsin C (2 μmol/L) induced oncosis in both the breast adenocarcinoma cells characterized by membrane blebbing and swelling, which was blocked by pretreatment with the pan-caspase inhibitor Z-VAD-fmk. In MCF-7 cells, fluopsin C caused PI uptake into the cells, significantly increased LDH release, induced cytoskeletal system degradation and ROS accumulation, decreased the intracellular ATP level and Δψm. Noticeably, fluopsin C exerted comparable cytotoxicity against the normal human hepatocytes (HL7702) and human mammary epithelial cells with the IC50 values at 24 h of 2.7 and 2.4 μmol/L, respectively. Oncotic cell death was involved in the anticancer effects of fluopsin C on human breast adenocarcinoma cells in vitro. The hepatoxicity of fluopsin C should not be ignored.
- Published
- 2013
10. Telekin Induces Apoptosis Associated with the Mitochondria-Mediated Pathway in Human Hepatocellular Carcinoma Cells
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Xia Li, Li-sha Ma, Bei-bei Zheng, Lehao Wu, Shan-Shan Liu, Wei-Dong Xie, and Lin Li
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Blotting, Western ,Pharmaceutical Science ,Apoptosis ,Mitochondria, Liver ,Asteraceae ,Biology ,Mitochondrion ,Flow cytometry ,Lactones ,chemistry.chemical_compound ,medicine ,Humans ,Sesquiterpenes, Eudesmane ,DAPI ,Cell Proliferation ,Membrane Potential, Mitochondrial ,Pharmacology ,medicine.diagnostic_test ,Hep G2 Cells ,General Medicine ,Phosphatidylserine ,Flow Cytometry ,medicine.disease ,Antineoplastic Agents, Phytogenic ,Molecular biology ,medicine.anatomical_structure ,chemistry ,Hepatocellular carcinoma ,Hepatocyte ,Cancer cell ,Calcium ,Apoptosis Regulatory Proteins ,Reactive Oxygen Species ,Drugs, Chinese Herbal - Abstract
Telekin, a eudesmane-type sesquiterpene lactone compound isolated from Chinese folk medicine Carpesium divaricatum, has been reported to strongly inhibit the proliferation of cancer cells. In this study, the involvement of a mitochondria-mediated pathway in the pro-apoptotic action of telekin was investigated in human hepatocellular carcinoma cells. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays showed that telekin exhibited excellent anti-proliferation activity in hepatocellular carcinoma cells and low cytotoxicity to normal hepatocyte cells. Telekin-induced apoptosis was characterized by chromatin condensation, formation of apoptotic bodies, and exposure of phosphatidylserine on the extracellular surface, as revealed by 4,6-diamidino-2-phenylindole (DAPI) nuclear staining and flow cytometry. Flow cytometry analysis showed that telekin induced the loss of mitochondrial membrane potential (MMP), as well as increased the levels of intracellular free calcium and reactive oxygen species (ROS). Additionally, Western blot results demonstrated that telekin induced the decrease in Apaf-1 and Bcl-2 expression, increase in Bax expression, release of cytochrome C, and activation of caspase-9 and caspase-3 in HepG-2 cells. These findings indicate that telekin activates the mitochondria-mediated apoptotic pathway in hepatocellular carcinoma cells and may merit further investigation as a potential therapeutic agent for the treatment of hepatocellular carcinoma.
- Published
- 2013
11. Security System of CNC Machine Tools Based on Artificial Intelligence
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Zhi Ping Guo, Yong Hong Dai, Hong Li Gao, Ying Li, Ji Ming Yan, and Bei Bei Zheng
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Engineering ,Artificial neural network ,business.industry ,Key (cryptography) ,Numerical control ,General Medicine ,Artificial intelligence ,business ,Manufacturing engineering ,Security system - Abstract
This paper proposes to establish a CNC machine tool security system using artificial intelligence-based, and discusses the key technologies: the dynamic fuzzy neural network(DFNN), and based on this, describes an established security system of CNC machine tool.
- Published
- 2012
12. 1-Oxoeudesm-11(13)-eno-12,8a-lactone induces G2/M arrest and apoptosis of human glioblastoma cells in vitro
- Author
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Bei-bei Zheng, Shan-Shan Liu, Lin Li, Xia Li, Yan-feng Wang, Li-sha Ma, and Wei-Dong Xie
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Cyclin-Dependent Kinase Inhibitor p21 ,Cell cycle checkpoint ,Aster Plant ,Apoptosis ,chemistry.chemical_compound ,Cell Line, Tumor ,Humans ,Sesquiterpenes, Eudesmane ,Pharmacology (medical) ,DAPI ,neoplasms ,Pharmacology ,Cyclin-dependent kinase 1 ,Brain Neoplasms ,Kinase ,Cell growth ,Cell Cycle Checkpoints ,General Medicine ,Cell cycle ,Antineoplastic Agents, Phytogenic ,Molecular biology ,Up-Regulation ,nervous system diseases ,Gene Expression Regulation, Neoplastic ,chemistry ,Cell culture ,Immunology ,Original Article ,Tumor Suppressor Protein p53 ,Glioblastoma ,DNA Damage - Abstract
To investigate the effects of 1-oxoeudesm-11(13)eno-12,8a-lactone (OEL), a novel eudesmane-type sesquiterpene isolated from Aster himalaicus, on the cell cycle and apoptosis in human glioblastoma cells in vitro.Human malignant glioblastoma cell lines U87 and A172 were used. The cytotoxicity of OEL was examined using the MTT assay. Cell apoptosis was assessed with DAPI staining and flow cytometry. DNA damage was determined by measuring the phosphorylation of H2AX using immunofluorescence staining and Western blotting. Cell cycle profiles were measured with flow cytometry. The mRNA expression of p53 and p21Waf1/Cip1 was investigated using real-time PCR. The protein expression of γ-H2AX, caspase-9, caspase-3, p53, p21Waf1/Cip1, cyclin B1, and cdc2 was analyzed with Western blotting.Treatment of the malignant glioblastoma cells with OEL inhibited the cell growth in dose- and time-dependent manners (the values of IC(50) at 48 and 72 h were 29.5 and 16.99 μmol/L, respectively, in U87 cells; 7.2 and 9.5 μmol/L, respectively, in A172 cells). OEL (10-30 μmol/L) induced apoptosis and G(2)/M phase arrest in both U87 and A172 cells. OEL induced the phosphorylation of cdc2, a G(2)/M phase cyclin-dependent kinase, and decreased the expression of cyclin B1 required for progression through the G(2)/M phase in U87 cells. The compound remarkably increased the phosphorylation of H2AX in U87 cells. Moreover, OEL increased the mRNA and protein levels of p53 and its target gene p21(Waf1/Cip1) in U87 cells. The compound also induced p53 phosphorylation. Pretreatment with PFT-α, a specific inhibitor of p53 transcriptional activity, could partially reverse the inhibition of OEL on the viability of U87 and A172 cells.OEL suppresses the growth of human glioblastoma cells in vitro via inducing DNA damage, p53-mediated cell cycle arrest and apoptosis, thus warrants further studies as a lead compound of anti-glioblastoma drug.
- Published
- 2012
13. Sorcin, a potential therapeutic target for reversing multidrug resistance in cancer
- Author
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Peng Zhang, Wei-Wei Jia, Xiu-Li Guo, Bei-Bei Zheng, and Lu-Gang Yu
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Physiology ,Chemistry ,Calcium-Binding Proteins ,Cancer ,Apoptosis ,General Medicine ,Drug resistance ,Human physiology ,medicine.disease ,Biochemistry ,Drug Resistance, Multiple ,Protein Structure, Tertiary ,Multiple drug resistance ,Drug Resistance, Neoplasm ,Gene Knockdown Techniques ,Neoplasms ,Cancer research ,medicine ,Animals ,Humans ,RNA Interference ,Reversing ,Sgc7901 cell ,ATP Binding Cassette Transporter, Subfamily B, Member 1 - Published
- 2012
14. Enantiomeric separation of (R, S)-naproxen by recycling high speed counter-current chromatography with hydroxypropyl-β-cyclodextrin as chiral selector
- Author
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Jizhong Yan, Liying Zhao, Shengqiang Tong, Bei Zheng, and Yi-Xin Guan
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Chromatography ,Resolution (mass spectrometry) ,Elution ,Chemistry ,beta-Cyclodextrins ,Organic Chemistry ,Aqueous two-phase system ,Stereoisomerism ,General Medicine ,Biochemistry ,High-performance liquid chromatography ,2-Hydroxypropyl-beta-cyclodextrin ,Absorption ,Analytical Chemistry ,Separation process ,Naproxen ,Countercurrent chromatography ,Enantiomer ,Enantiomeric excess ,Countercurrent Distribution - Abstract
Recycling high speed counter-current chromatography (HSCCC) was successfully applied to resolution of (R, S)-naproxen (NAP) using hydroxypropyl-β-cyclodextrin (HP-β-CD) as chiral selector. The two-phase solvent system composed of n-hexane–ethyl acetate–0.1 mol L−1 phosphate buffer solution with pH = 2.67 (8:2:10, v/v/v) was selected. Influence factors for the chiral separation process were investigated, including concentration of HP-β-CD, equilibrium temperature and pH of aqueous phase. Suitable elution mode was selected for HSCCC enantioseparation of (R, S)-NAP. Under optimum separation conditions, 29 mg of (R, S)-NAP was separated using preparative recycling HSCCC with the molar ratio HP-β-CD/NAP racemate 83:1. Technical details for recycling elution mode were discussed as for chiral HSCCC separation. The purities of both (S)-NAP and (R)-NAP were over 99.5% as determined by HPLC. Enantiomeric excess of (S)-NAP and (R)-NAP reached 99.4%. Recovery for NAP enantiomers from HSCCC fractions was 82–89%, yielding 13 mg of (S)-NAP and 12 mg of (R)-NAP.
- Published
- 2011
15. The Research of Harmonious Society Index System and Positive Analysis
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Bei Bei Zheng and Xin Yu
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Index system ,Beijing ,Harmonious Society ,Analytic hierarchy process ,General Medicine ,Sociology ,Economic system - Abstract
By using the existing research experience and through the in-depth study of the harmonious society theory, this paper sets up a harmonious society index system. Moreover, based on this result and by making use of the method of AHP, this paper carries positive analysis on the construction of harmonious society of Beijing City.
- Published
- 2011
16. A novel Ta.AGP.S.1b transcript in Chinese common wheat (Triticum aestivum L.)
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Guozhang Kang, Tiancai Guo, Bing-Quan Shen, Bei-Bei Zheng, and Huifang Peng
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China ,DNA, Complementary ,DNA, Plant ,Molecular Sequence Data ,Glucose-1-Phosphate Adenylyltransferase ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Endosperm ,Exon ,Species Specificity ,Complementary DNA ,Amino Acid Sequence ,RNA, Messenger ,Cloning, Molecular ,Common wheat ,Gene ,Peptide sequence ,Phylogeny ,Triticum ,Genetics ,Base Sequence ,General Immunology and Microbiology ,Chromosome Mapping ,food and beverages ,Sequence Analysis, DNA ,General Medicine ,genomic DNA ,Seeds ,Hordeum vulgare ,General Agricultural and Biological Sciences - Abstract
ADP-glucose pyrophosphorylase (AGPase), the key enzyme of starch synthesis in plants, is composed of two small and two large subunits, and has plastidial and cytosolic isoforms. In kernels of wheat ( Triticum aestivum L . ) and barley ( Hordeum vulgare L.), transcripts for cytosolic ( Ta.AGP.S1a ) and plastidial ( Ta.AGP.S1b ) small subunits of AGPase were encoded by the same gene ( Ta.AGP.S.1 ) by use of the alternative first exons. In this study, a cDNA sequence (1631 bp) [NCBI: EU586278] encoding a novel Ta.AGP.S1b transcript was isolated in kernels of Chinese common wheat cultivars. Compared with another Ta.AGP.S1b transcript [NCBI: FJ643609] isolated in kernels of non-Chinese wheat cultivars, EU586278 lacked a long fragment (117 bp) at its 5′terminal, resulting in a shorten transit peptide. The lacked fragments of Ta.AGP.S1b (EU586278) were universally found in surveyed 22 Chinese common wheat cultivars. Partial genomic DNA sequence [NCBI: FJ907395 ] of Ta.AGP.S.1 gene, which was corresponded to 5′terminal of EU586278 transcript, was also isolated in Chinese common cultivars and sequencing indicated that FJ907395 contained the corresponding lacked fragment of EU586278 transcript, inferring the lacked fragment in EU586278 transcript was not present in the genome, but possibly occurred at transcription level. Using TargetP software, the predicated transit peptide of putative plastidial SSU encoded by EU586278 contained merely 25 amino acids, considerably shorter than those of other plant AGP. S.1bs (54–70 amino acids). Phylogenetic tree analysis indicated that the amino acid sequence of EU586278 transit peptide was not clustered together with those of other wheat Ta.AGP.S1bs [NCBI: AF536819 and FJ643609] and barley AGP.S1b [NCBI: Z48563]. These implied that EU586278 could be a novel Ta.AGP.S1b transcript. Semi-quantitative PCR analysis indicated that transcripts of EU586278 were abundantly expressed in leaf, moderately in endosperm and stem, and weakly in root.
- Published
- 2010
17. 3β-Angeloyloxy-8β,10β-dihydroxyeremophila-7(11)-en-12,8α-lactone Inhibits Lipopolysaccharide-Induced Nitric Oxide Production in RAW264.7 Cells
- Author
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Xin-Xin Zhao, Lin Li, Li-sha Ma, Xiao Sun, Wei-Dong Xie, Bei-bei Zheng, Chang-you Jiang, Juan-juan Chang, and Xia Li
- Subjects
MAPK/ERK pathway ,Lipopolysaccharides ,Lipopolysaccharide ,p38 mitogen-activated protein kinases ,Anti-Inflammatory Agents ,Pharmaceutical Science ,Nitric Oxide Synthase Type II ,Asteraceae ,Nitric Oxide ,Nitric oxide ,chemistry.chemical_compound ,Lactones ,Mice ,NF-KappaB Inhibitor alpha ,Animals ,Protein kinase A ,Pharmacology ,Inflammation ,biology ,Chemistry ,Kinase ,NF-kappa B ,General Medicine ,Molecular biology ,Nitric oxide synthase ,RAW 264.7 Cells ,biology.protein ,Cytokines ,Tumor necrosis factor alpha ,I-kappa B Proteins ,Inflammation Mediators ,Reactive Oxygen Species ,Sesquiterpenes ,Drugs, Chinese Herbal - Abstract
Farfugium japonicum (L.) KITAM, named "Lian-Peng-Cao" in China, has been traditionally used in Chinese folk medicine to treat sore throat, cold and cough due to its anti-inflammatory properties. In this study, the anti-inflammatory action of 3β-angeloyloxy-8β,10β-dihydroxyeremophila-7(11)-en-12,8α-lactone (FJ1) isolated from Farfugium japonicum and its molecular mechanism in RAW264.7 cells were investigated. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that FJ1 with or without 3 µg/mL lipopolysaccharide (LPS) had no significant cytotoxicity in RAW264.7 cells. The production of nitric oxide (NO) was identified with a Griess reagent kit. The mRNA expression of inducible nitric oxide synthase (iNOS) and cytokines, including tumor necrosis factor α (TNF-α) and cyclooxygenase-2 (COX-2), was measured by real-time polymerase chain reaction (PCR). Reactive oxygen species (ROS) production was detected by flow cytometry analysis. Western blot was used to examine the protein expression of nuclear factor-kappa B (NF-κB)/p65, inhibitor of kappa B (IκB)-α, phosphorylated IκB-α (p-IκB-α), mitogen-activated protein kinase (MAPK) molecules, iNOS, and TNF-α. We discovered that FJ1 possesses anti-inflammatory effects that inhibit the release of LPS-stimulated pro-inflammatory cytokines, including NO and ROS. The molecular mechanism of FJ1-mediated anti-inflammation is associated with decreasing phosphorylation of MAPK molecules, including extracellular signal-related kinase 1/2 (ERK1/2), p38 MAPK, and c-Jun NH2-terminal kinase (JNK), FJ1 also reverses IκB degradation and attenuates the mRNA and protein expression of NF-κB-related downstream inducible enzymes and cytokines, such as iNOS, TNF-α in RAW264.7 cells. The results suggest that FJ1 has anti-inflammatory properties, which indicates that F. japonicum can be utilized to treat inflammatory diseases. The potential mechanism is associated with the NF-κB and MAPK activation pathways in LPS-stimulated macrophages.
- Published
- 2015
18. Streptomyces lopnurensis sp. nov., an actinomycete isolated from soil
- Author
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Chuan-Xing Wan, Li-Li Zhang, Xiao-Xue Han, Zhan-Feng Xia, and Bei Zheng
- Subjects
DNA, Bacterial ,China ,Streptomyces lopnurensis ,Sequence analysis ,Molecular Sequence Data ,Diamino acid ,Biology ,Diaminopimelic Acid ,Microbiology ,chemistry.chemical_compound ,RNA, Ribosomal, 16S ,Ecology, Evolution, Behavior and Systematics ,Mycelium ,Phylogeny ,Soil Microbiology ,Base Composition ,Strain (chemistry) ,Fatty Acids ,Vitamin K 2 ,General Medicine ,Sequence Analysis, DNA ,Ribosomal RNA ,16S ribosomal RNA ,Streptomyces ,Streptomyces sodiiphilus ,Bacterial Typing Techniques ,chemistry ,Biochemistry - Abstract
A novel actinomycete, designated strain TRM 49590T, was isolated from a soil sample from Lop Nur in Xinjiang Province, China. Strain TRM 49590T was aerobic, Gram-staining-positive, with an optimum NaCl concentration for growth of 1.5 % (w/v) and an optimum temperature for growth of 28–37 °C. The aerial mycelium was sparse, cylindrical and smooth-surfaced with irregular branches on ISP medium 4. The whole-cell sugars of strain TRM 49590T were ribose and glucose. The diagnostic diamino acid contained ll-diaminopimelic acid. The predominant menaquinones were MK-9(H6) and MK-9(H8), with MK-9(H4) and MK-10(H6) present in smaller amounts. The major fatty acids were iso-C16 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. The G+C content of the genomic DNA was 62.2 mol%. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol and phosphatidylinositol mannoside. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain TRM 49590T belongs to the genus Streptomyces with a sequence similarity of 97.16 % with the most closely related species Streptomyces sodiiphilus . Based on these observations, strain TRM 49590T is proposed to represent a novel species of the genus Streptomyces for which the name Streptomyces lopnurensis sp. nov. is suggested. The type strain is TRM 49590T ( = CCTCC AA 2013018T = NRRL B59109T).
- Published
- 2014
19. Telekin suppresses human hepatocellular carcinoma cells in vitro by inducing G2/M phase arrest via the p38 MAPK signaling pathway
- Author
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Wei-Dong Xie, Li-sha Ma, Bei-bei Zheng, Juan-juan Chang, Lin Li, Xia Li, and Xiao Sun
- Subjects
Cell cycle checkpoint ,Carcinoma, Hepatocellular ,Cell Survival ,Apoptosis ,Biology ,Protein Serine-Threonine Kinases ,p38 Mitogen-Activated Protein Kinases ,Cyclin-dependent kinase ,Cell Line, Tumor ,CDC2 Protein Kinase ,Humans ,Sesquiterpenes, Eudesmane ,cdc25 Phosphatases ,Pharmacology (medical) ,MTT assay ,Viability assay ,Cyclin B1 ,Cell Proliferation ,Pharmacology ,Cell growth ,Liver Neoplasms ,Intracellular Signaling Peptides and Proteins ,General Medicine ,Cell Cycle Checkpoints ,Hep G2 Cells ,Cell cycle ,Molecular biology ,Cyclin-Dependent Kinases ,Cell biology ,G2 Phase Cell Cycle Checkpoints ,Cancer cell ,biology.protein ,Original Article ,Reactive Oxygen Species ,Signal Transduction - Abstract
Telekin, isolated from the Chinese herb Carpesium divaricatum, has shown anti-proliferation effects against various cancer cells, including hepatocellular carcinoma cells. In this study, we investigated the anti-proliferation mechanisms of telekin in human hepatocellular carcinoma HepG2 cells in vitro. HepG2 cells were treated with telekin. Cell viability was evaluated using MTT assay. Flow cytometry was used to measure cell cycle profiles, ROS level and apoptosis. The protein expression levels were analyzed with Western blotting. Telekin (3.75–30 μmol/L) dose-dependently inhibited the viability of HepG2 cells and induced l apoptosis. Furthermore, the treatment induced cell cycle arrest at G2/M phase, accompanied by significantly increased the phosphorylation of Cdc25A and Cdc2, and decreased Cyclin B1 level. Moreover, the treatment significantly stimulated ROS production, and increased the phosphorylation of p38 and MAPKAPK-2 in the cells. Pretreatment with the antioxidant NAC (2.5, 5, and 10 mmol/L), or the p38 MAPK inhibitor SB203580 (2.5 and 5 μmol/L) dose-dependently attenuated these telekin-induced effects in the cells. Telekin suppresses hepatocellular carcinoma cells in vitro by inducing G2/M phase arrest via activating the p38 MAPK pathway.
- Published
- 2014
20. ChemInform Abstract: Unexpected and Divergent Reactions of N-Formyl-1,2-dihydroquinolines with Sodium Azide: Highly Chemoselective Formation of 2-Substituted Quinolines and Isoxazolo[4,3-d]quinolines
- Author
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Jingbo Yu, Zhenhua Li, Bei Zheng, and Weike Su
- Subjects
chemistry.chemical_compound ,Chemistry ,Sodium azide ,Organic chemistry ,General Medicine - Published
- 2010
21. Ligustrazine derivate DLJ14 reduces multidrug resistance of K562/A02 cells by modulating GSTπ activity
- Author
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Xiu-Li Guo, Yu'ning Song, Bei-Bei Zheng, Xue Dong, Xinyong Liu, Lu-Gang Yu, and Yan-Na Cheng
- Subjects
Blotting, Western ,Down-Regulation ,Pharmacology ,Biology ,Toxicology ,chemistry.chemical_compound ,Western blot ,Downregulation and upregulation ,hemic and lymphatic diseases ,medicine ,Cytotoxic T cell ,Humans ,RNA, Messenger ,Cell Proliferation ,Antibiotics, Antineoplastic ,medicine.diagnostic_test ,Kinase ,Reverse Transcriptase Polymerase Chain Reaction ,General Medicine ,Glutathione ,Drug Resistance, Multiple ,Multiple drug resistance ,chemistry ,Glutathione S-Transferase pi ,Verapamil ,Doxorubicin ,Drug Resistance, Neoplasm ,Pyrazines ,Cancer cell ,Leukemia, Erythroblastic, Acute ,K562 Cells ,K562 cells - Abstract
Multidrug resistance (MDR) of tumor cells is a major obstacle in chemotherapeutic cancer treatment. Over-expression of glutathione S-transferase π (GSTπ) is one of the mechanisms contributing to MDR. In this study, we investigated the reversal of MDR by DLJ14, a ligustrazine derivate, in adriamycin (Adr) resistant human myelogenous leukemia (K562/A02) cells by modulating the expression of GSTπ and the activity of GST-related enzymes. In the MTT test, DLJ14 showed a weak inhibition on proliferation of both K562/A02 and K562 cells, while verapamil at the same concentration showed a much stronger inhibition. The sensitivity of K562/A02 cells to cytotoxic killing by Adr was enhanced by incubation with DLJ14 as a result of the increased intracellular accumulation of Adr. The accumulation of Adr induced by DLJ14 may due to down regulation of GST-related enzyme activity. Western blot analysis and RT-PCR showed that DLJ14 was able to inhibit the protein expression and mRNA expression of GSTπ in K562/A02 cells. Moreover, DLJ14 increased the expression of cellular c-Jun NH 2 -terminal kinase (JNK) in K562/A02 cells exposure to Adr. This is consistent with the inhibition of GSTπ. These results demonstrate that DLJ14 may be an attractive new agent for the chemosensitization of cancer cells.
- Published
- 2010
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