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Regulation of exogenous bFGF gene mediated by recombinant adeno-associated virus

Ke SONG, Nianjing RAO, Meiling CHEN, Yingguang CAO

《医学前沿(英文)》 2009年 第3卷 第2期   页码 158-163 doi: 10.1007/s11684-009-0042-5

摘要: The regulatory effect of basic fibroblast growth factor (bFGF) mediated by recombinant adeno-associated virus (AAV) was investigated. Recombinant plasmid pAAV-S3-bFGF, and pSVneo were co-transfected into BHK-21 cells, then the recombinant AAV genome was replicated and packaged with the helper virus HSV1-rc/ΔUL2. The titer of the recombinant rAAV2-tet-off-bFGF was determined by dot-blot assay. MC3T3-E1 cells were infected with rAAV2-tet-off-bFGF. Regulatory effects of Doxycycline (Dox) on bFGF and osteogenic factors were assayed quantitatively by real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. The physical particle titer of rAAV2-tet-off-bFGF successfully constructed was 1.8×10 vector genomes/mL, and the virus could infect MC3T3-E1 cells effectively. In MC3T3-E1 cells treated with Dox, the expression levels of exogenous bFGF and osteogenic factors declined to varying degrees. It was concluded that rAAV2-tet-off-bFGF could infect MC3T3 cells efficiently, and this recombinant system could be regulated successfully by Dox .

关键词: tetracycline regulatory system     adeno-associated virus     basic fibroblast growth factor     gene regulation    

The regulatory sciences for stem cell-based medicinal products

null

《医学前沿(英文)》 2014年 第8卷 第2期   页码 190-200 doi: 10.1007/s11684-014-0323-5

摘要:

Over the past few years, several new achievements have been made from stem cell studies, many of which have moved up from preclinical stages to early, or from early to middle or late, stages thanks to relatively safe profile and preliminary evidence of effectiveness. Moreover, some stem cell-based products have been approved for marketing by different national regulatory authorities. However, many critical issues associated mainly with incomplete understanding of stem cell biology and the relevant risk factors, and lack of effective regulations still exist and need to be urgently addressed, especially in countries where establishment of appropriate regulatory system just commenced. More relevantly, the stem cell regulatory sciences need to be established or improved to more effectively evaluate quality, safety and efficacy of stem cell products, and for building up the appropriate regulatory framework. In this review, we summarize some new achievements in stem cell studies, especially the preclinical and clinical studies, the existing regulations, and the associated challenges, and we then propose some considerations for improving stem cell regulatory sciences with a goal of promoting the steadfast growth of the well-regulated stem cell therapies abreast of evolvement of stem cell sciences and technologies.

关键词: stem cell-based medicinal products (SCMPs)     stem cell therapy (SCT)     safety     effectiveness     standards     guidelines     regulatory science    

Optimized determination of airborne tetracycline resistance genes in laboratory atmosphere

Lu Song, Can Wang, Yizhu Wang

《环境科学与工程前沿(英文)》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1274-5

摘要: Abstract • Sampling parameters with high efficiency was determined. • Operational process to detect airborne ARGs was optimized. • Providing research basis to control airborne ARGs of a laboratory atmosphere Antibiotic resistance genes (ARGs) have been detected in various atmospheric environments. Airborne ARGs transmission presents the public health threat. However, it is very difficult to quantify airborne ARGs because of the limited availability of collectable airborne particulate matter and the low biological content of samples. In this study, an optimized protocol for collecting and detecting airborne ARGs was presented. Experimental results showed that recovery efficiency tended to increase initially and then declined over time, and a range of 550–780 copies/mm2 of capture loading was recommended to ensure that the recovery efficiency is greater than 75%. As the cell walls were mechanically disrupted and nucleic acids were released, the buffer wash protects ARGs dissolution. Three ratios of buffer volume to membrane area in buffer wash were compared. The highest concentrations of airborne ARGs were detected with 1.4 µL/mm2 buffer wash. Furthermore, the majority of the cells were disrupted by an ultrasonication pretreatment (5 min), allowing the efficiency ARGs detection of airborne samples. While, extending the ultrasonication can disrupt cell structures and gene sequence was broken down into fragments. Therefore, this study could provide a theoretical basis for the efficient filter collection of airborne ARGs in different environments. An optimized sampling method was proposed that the buffer wash was 1.4 µL/mm2 and the ultrasonication duration was 5 min. The indoor airborne ARGs were examined in accordance with the improved protocol in two laboratories. The result demonstrated that airborne ARGs in an indoor laboratory atmosphere could pose the considerable health risk to inhabitants and we should pay attention to some complicated indoor air environment.

关键词: Airborne tetracycline resistance genes     Filter sampling     Capture loading     Membrane pretreatment     Indoor laboratory atmosphere    

Gold modified microelectrode for direct tetracycline detection

Hongtao WANG, Huimin ZHAO, Xie QUAN

《环境科学与工程前沿(英文)》 2012年 第6卷 第3期   页码 313-319 doi: 10.1007/s11783-011-0323-5

摘要: The residues of tetracycline antibiotics in water have attracted many concerns due to their harmful impact to human health. This paper reports an electrochemical sensor for the determination of tetracycline (TC) by the microelectrode, which was fabricated by electrodeposited gold colloids on tungsten tip. Cyclic voltammerty was used to study the electrochemical behavior of TC on the microelectrode. Well anodic wave was obtained at about 1.5 V in acidic solutions. Electrochemical determination of tetracycline was investigated using microelectrode by cyclic voltammetry. Under optimized conditions, the calibration curves for TC were obtained. The oxidation peak currents were linearly related to TC concentrations in the range of 1–10 mg·L and 10–100 mg·L , respectively. The detection limit was 0.09 mg·L ( / = 3).

关键词: microelectrode     tungsten tip     gold colloids     tetracycline    

Erratum to: Optimized determination of airborne tetracycline resistance genes in laboratory atmosphere

Lu Song, Can Wang, Yizhu Wang

《环境科学与工程前沿(英文)》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1289-y

Effective degradation of tetracycline by mesoporous Bi

Xiaolong CHU,Guoqiang SHAN,Chun CHANG,Yu FU,Longfei YUE,Lingyan ZHU

《环境科学与工程前沿(英文)》 2016年 第10卷 第2期   页码 211-218 doi: 10.1007/s11783-014-0753-y

摘要: Bi WO was synthesized with a hydrothermal method at different pHs and used for the degradation of tetracycline (TC) in water. The mesoporous Bi WO prepared at pH 1 (BWO-1) displayed the highest adsorption and degradation capacity to TC due to its large surface area and more efficient capacity to separate photogenerated electrons and holes. 97% of TC at 20 mg·L was removed by BWO-1 at 0.5 g·L after 120 min irradiation under simulated solar light. Only 31% of the total organic carbon (TOC) was removed after 360 min irradiation although the TC removal reached 100%, suggesting that TC was mainly transformed to intermediate products rather than completely mineralized. The intermediates were identified by high-performance liquid chromatography-time of flight-mass spectrometry (HPLC-TOF-MS) and possible photodegradation pathways were proposed.

关键词: Bi2WO6     hydrothermal synthesis     tetracycline (TC)     photocatalysis    

Sorption of tetracycline to sediments and soils: assessing the roles of pH, the presence of cadmium and

Guixiang ZHANG, Xitao LIU, Ke SUN, Ye ZHAO, Chunye LIN

《环境科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 421-429 doi: 10.1007/s11783-010-0265-3

摘要: Batch sorption experiments were conducted to evaluate the sorption behavior of tetracycline (TC, H L) on sediments and soils in the presence and absence of cadmium (Cd), as affected by pH and properties of sediments and soils. The results indicated stronger nonlinearity and higher capacity of TC sorption on sediments than on soils. Sorption of TC also strongly depended on environmental factors and sediment/soil properties. Lower pH facilitated TC sorption through a cation exchange mechanism, which also took place at pH values above 5.5, where TC existed as a zwitterion (H L ) or anions (HL and L ). When pH was above 7, however, ligand-promoted dissolution of TC might occur due to TC weakening the Al-O bond of aluminum oxide and the Fe-O bond of iron oxide. Natural organic matter (NOM) plays a more important role in TC sorption than cation exchange capacity (CEC) and clay contents. The presence of Cd (II) increased TC sorption on both sediments and soils, which resulted from the decrease of equilibrium solution pH caused by Cd exchange with H ions of sediment/soil surfaces. The increase of TC sorption was also related to the formation of TC-Cd complexes, where Cd acted as a bridge between the sediment/soil and TC.

关键词: sorption     tetracycline (TC)     pH     cadmium (Cd)     antibiotic    

Immobilization of NZVI in polydopamine surface-modified biochar for adsorption and degradation of tetracycline

Xiangyu Wang, Weitao Lian, Xin Sun, Jun Ma, Ping Ning

《环境科学与工程前沿(英文)》 2018年 第12卷 第4期 doi: 10.1007/s11783-018-1066-3

摘要:

Novel method for polydopamine (PDA) modified biochar (BC) with immobilized NZVI.

PDA/NZVI@BC exhibits significantly enhanced activity for tetracycline (TC) removal.

TC removal efficiency was increased by 55.9% compared with that of pristine NZVI.

The mechanism of tetracycline removal by PDA/NZVI@BC was proposed.

关键词: Biochar     Polydopamine     NZVI     Modification     Tetracycline    

In situ formation of bimetallic FeNi nanoparticles on sand through green technology: Application for tetracycline

Ravikumar KVG, Debayan Ghosh, Mrudula Pulimi, Chandrasekaran Natarajan, Amitava Mukherjee

《环境科学与工程前沿(英文)》 2020年 第14卷 第1期 doi: 10.1007/s11783-019-1195-3

摘要: • In situ preparation of FeNi nanoparticles on the sand via green synthesis approach. • Removal of tetracycline using GS-FeNi in batch and column study. • Both reductive degradation and sorption played crucial role the process. • Reusability of GS-FeNi showed about 77.39±4.3% removal on 4th cycle. • TC by-products after interaction showed less toxic as compared with TC. In this study, FeNi nanoparticles were green synthesized using Punica granatum (pomegranate) peel extract, and these nanoparticles were also formed in situ over quartz sand (GS-FeNi) for removal of tetracycline (TC). Under the optimized operating conditions, (GS-FeNi concentration: 1.5% w/v; concentration of TC: 20 mg/L; interaction period: 180 min), 99±0.2% TC removal was achieved in the batch reactor. The removal capacity was 181±1 mg/g. A detailed characterization of the sorbent and the solution before and after the interaction revealed that the removal mechanism(s) involved both the sorption and degradation of TC. The reusability of reactant was assessed for four cycles of operation, and 77±4% of TC removal was obtained in the cycle. To judge the environmental sustainability of the process, residual toxicity assay of the interacted TC solution was performed with indicator bacteria (Bacillus and Pseudomonas) and algae (Chlorella sp.), which confirmed a substantial decrease in the toxicity. The continuous column studies were undertaken in the packed bed reactors using GS-FeNi. Employing the optimized conditions, quite high removal efficiency (978±5 mg/g) was obtained in the columns. The application of GS-FeNi for antibiotic removal was further evaluated in lake water, tap water, and ground water spiked with TC, and the removal capacity achieved was found to be 781±5, 712±5, and 687±3 mg/g, respectively. This work can pave the way for treatment of antibiotics and other pollutants in the reactors using novel green composites prepared from fruit wastes.

关键词: GS-FeNi nanoparticles     Tetracycline removal     Re-usability     Residual toxicity     Column studies    

Zero E-waste: Regulatory impediments and blockchain imperatives

Mengjun Chen, Oladele A. Ogunseitan

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1402-x

摘要: Abstract • Copyrights on electronic products are impediments in promoting circular economy. • Manufacturers antagonize refurbishment and remanufacturing to maximize profit. • International harmonization of copyright laws will aid repair and remanufacture. • Blockchain–digital immutable ledgers–can promote trust among stakeholders. The concept of zero waste is an ideal situation that will require different solutions for different categories of waste. Electronic waste (E-waste), the fastest growing category of solid hazardous waste presents various unique challenges. Electronic product repair, reuse and remanufacture (3re) are crucial for effective source reduction of E-waste and the integration of the electronics industry into a circular or zero-waste economy framework. Increasingly, 3re implementation is restricted by regulatory difficulties, particularly the invocation of copyright laws. Here, we use the examples of electronic printer cartridges and restored compact discs (CDs) to identify the challenges and to explore solutions for managing the risks associated with E-waste through circular economy and the opportunities presented by innovative Blockchain solutions. A set of international consensuses on judicial definitions, such as 3re, refurbish fake/counterfeit product and copyright exhaustion, are proposed to accelerate source reduction in E-waste management toward the goal of zero waste.

关键词: Blockchain     E-waste     Regulatory Policy     Copyright Laws     Repair-Reuse-Remanufacture     Toxicity    

Disinfection byproducts in drinking water and regulatory compliance: A critical review

Xiaomao WANG,Yuqin MAO,Shun TANG,Hongwei YANG,Yuefeng F. XIE

《环境科学与工程前沿(英文)》 2015年 第9卷 第1期   页码 3-15 doi: 10.1007/s11783-014-0734-1

摘要: Disinfection by-products (DBPs) are regulated in drinking water in a number of countries. This critical review focuses on the issues associated with DBP regulatory compliance, including methods for DBP analysis, occurrence levels, the regulation comparison among various countries, DBP compliance strategies, and emerging DBPs. The regulation comparison between China and the United States (US) indicated that the DBP regulations in China are more stringent based on the number of regulated compounds and maximum levels. The comparison assessment using the Information Collection Rule (ICR) database indicated that the compliance rate of 500 large US water plants under the China regulations is much lower than that under the US regulations (e.g. 62.2% versus 89.6% for total trihalomethanes). Precursor removal and alternative disinfectants are common practices for DBP regulatory compliance. DBP removal after formation, including air stripping for trihalomethane removal and biodegradation for haloacetic acid removal, have gained more acceptance in DBP control. Formation of emerging DBPs, including iodinated DBPs and nitrogenous DBPs, is one of unintended consequences of precursor removal and alternative disinfection. At much lower levels than carbonaceous DBPs, however, emerging DBPs have posed higher health risks.

关键词: Disinfection byproducts (DBPs)     drinking water standards     regulatory compliance     alternative disinfection     information collection rule (ICR)     emerging DBPs    

Liver cell therapies: cellular sources and grafting strategies

《医学前沿(英文)》 2023年 第17卷 第3期   页码 432-457 doi: 10.1007/s11684-023-1002-1

摘要: The liver has a complex cellular composition and a remarkable regenerative capacity. The primary cell types in the liver are two parenchymal cell populations, hepatocytes and cholangiocytes, that perform most of the functions of the liver and that are helped through interactions with non-parenchymal cell types comprising stellate cells, endothelia and various hemopoietic cell populations. The regulation of the cells in the liver is mediated by an insoluble complex of proteins and carbohydrates, the extracellular matrix, working synergistically with soluble paracrine and systemic signals. In recent years, with the rapid development of genetic sequencing technologies, research on the liver’s cellular composition and its regulatory mechanisms during various conditions has been extensively explored. Meanwhile breakthroughs in strategies for cell transplantation are enabling a future in which there can be a rescue of patients with end-stage liver diseases, offering potential solutions to the chronic shortage of livers and alternatives to liver transplantation. This review will focus on the cellular mechanisms of liver homeostasis and how to select ideal sources of cells to be transplanted to achieve liver regeneration and repair. Recent advances are summarized for promoting the treatment of end-stage liver diseases by forms of cell transplantation that now include grafting strategies.

关键词: liver regeneration     hepatocytes     cholangiocytes     stem cells     organoids     regulatory mechanisms     transplantation/grafting strategies    

a novel anion exchange group modified hyper-crosslinked resin for the effective adsorption of both tetracycline

Qing ZHOU, Mengqiao WANG, Aimin LI, Chendong SHUANG, Mancheng ZHANG, Xiaohan LIU, Liuyan WU

《环境科学与工程前沿(英文)》 2013年 第7卷 第3期   页码 412-419 doi: 10.1007/s11783-013-0483-6

摘要: A novel hyper-crosslinked resin (MENQ) modified with an anion exchange group was prepared using divinylbenzene (DVB) and methyl acrylate (MA) as comonomers via four steps: suspension polymerization, post-crosslinking, ammonolysis and alkylation reactions. The obtained resin had both a high specific surface area (793.34 m ·g ) and a large exchange capacity (strong base anion exchange capacity, SEC: 0.74 mmol·g , weak base anion exchange capacity, WEC: 0.45 mmol·g ). XAD-4 was selected as an adsorbent for comparison to investigate the adsorption behavior of tetracycline (TC) and humic acid (HA) onto the adsorbents. The results revealed that MENQ could effectively remove both TC and HA. The adsorption capacity of XAD-4 for TC was similar to that of MENQ, but XAD-4 exhibited poor performance for the adsorption of HA. The adsorption isotherms of TC and HA were well-fitted with the Freundlich model, which indicated the existence of heterogeneous adsorption through cation-π bonding and π–π interactions. The optimal solution condition for the adsorption of TC was at a pH of 5–6, whereas the adsorption of HA was enhanced with increasing pH of the solution.

关键词: high surface area     adsorption     anion exchange     micropollutant     dissolved organic matters    

METABOLIC AND TRANSCRIPTOME ANALYSIS REVEALS METABOLITE VARIATION AND FLAVONOID REGULATORY NETWORKS IN

《农业科学与工程前沿(英文)》 2021年 第8卷 第2期

摘要:

Metabolites, especially secondary metabolites, are very important in the adaption of tea plants and the quality of tea products. Here, we focus on the seasonal variation in metabolites of fresh tea shoots and their regulatory mechanism at the transcriptional level. The metabolic profiles of fresh tea shoots of 10 tea accessions collected in spring, summer, and autumn were analyzed using ultra-performance liquid chromatography coupled with quadrupole-obitrap mass spectrometry. We focused on the metabolites and key genes in the phenylpropanoid/flavonoid pathway integrated with transcriptome analysis. Multivariate statistical analysis indicates that metabolites were distinctly different with seasonal alternation. Flavonoids, amino acids, organic acids and alkaloids were the predominant metabolites. Levels of most key genes and downstream compounds in the flavonoid pathway were lowest in spring but the catechin quality index was highest in spring. The regulatory pathway was explored by constructing a metabolite correlation network and a weighted gene co-expression network.

 

Assessing combined toxic effects of tetracycline and P25 titanium dioxide nanoparticles using

Barsha Roy, Khushboo Kadam, Suresh Palamadai Krishnan, Chandrasekaran Natarajan, Amitava Mukherjee

《环境科学与工程前沿(英文)》 2021年 第15卷 第1期 doi: 10.1007/s11783-020-1298-x

摘要: Abstract • UVA pre-irradiation to TiO2 NPs enhanced its toxicity toward plant A. cepa. • UVA TiO2 NPs increased intracellular ROS, resulting in more cell damage. • Cell death enhanced cell permeability and increased uptake of NPs. • Being highly toxic (EC50 = 0.097 µmol/L), TC did not increase ROS generation. • Even at a low dose, TC enhanced the toxic potential of TiO2 NPs significantly. Usage of titanium dioxide nanoparticles (TiO2 NPs) and tetracycline (TC) has increased significantly in the present era. This leads to their release and accumulation in the environment. Both the compounds, individually, can have adverse toxic effects on the plants. Their binary mixtures can increase this degree of damage. The present study aimed to evaluate the toxicity of both the contaminants in individual and binary mixtures in Allium cepa. Further, the toxicity of TiO2 NPs upon UVA pre-irradiation was also measured. Results showed that UVA pre-irradiated NPs (UVA-TiO2 NPs) had a significant decrease in cell viability than their non-irradiated counterparts (NI-TiO2), denoting an increase in photocatalytic activity upon UVA pre-irradiation. Very low concentrations of TC (EC10 = 0.016 µmol/L) mixed with TiO2 NPs significantly increased the toxicity for both UVA-TiO2 and NI-TiO2 NPs. Intracellular ROS generation was significantly high for UVA-TiO2 NPs. However, TC did not have any effects on ROS production. Both the compounds exhibited genotoxic potential in A. cepa. Different chromosomal abnormalities like anaphase bridges, telophase bridges, laggard chromosomes, binucleate cells, etc. were observed. The binary mixture of UVA-TiO2 NPs and TC showed the highest chromosomal aberrations (64.0%±1.26%) than the mixture with NI-TiO2 or the individual contaminants. This decreased significantly after recovery (46.8%±1.92%), denoting the self-repair processes. This study proved that UVA-TiO2 NPs were more toxic and could be enhanced further when mixed with a sub-lethal concentration of TC. This work will help to assess the risk of both compounds in the environment.

关键词: Binary toxicity     Cell viability     Mitotic index     Chromosomal aberration     Reactive oxygen species     Nanoparticles internalization    

标题 作者 时间 类型 操作

Regulation of exogenous bFGF gene mediated by recombinant adeno-associated virus

Ke SONG, Nianjing RAO, Meiling CHEN, Yingguang CAO

期刊论文

The regulatory sciences for stem cell-based medicinal products

null

期刊论文

Optimized determination of airborne tetracycline resistance genes in laboratory atmosphere

Lu Song, Can Wang, Yizhu Wang

期刊论文

Gold modified microelectrode for direct tetracycline detection

Hongtao WANG, Huimin ZHAO, Xie QUAN

期刊论文

Erratum to: Optimized determination of airborne tetracycline resistance genes in laboratory atmosphere

Lu Song, Can Wang, Yizhu Wang

期刊论文

Effective degradation of tetracycline by mesoporous Bi

Xiaolong CHU,Guoqiang SHAN,Chun CHANG,Yu FU,Longfei YUE,Lingyan ZHU

期刊论文

Sorption of tetracycline to sediments and soils: assessing the roles of pH, the presence of cadmium and

Guixiang ZHANG, Xitao LIU, Ke SUN, Ye ZHAO, Chunye LIN

期刊论文

Immobilization of NZVI in polydopamine surface-modified biochar for adsorption and degradation of tetracycline

Xiangyu Wang, Weitao Lian, Xin Sun, Jun Ma, Ping Ning

期刊论文

In situ formation of bimetallic FeNi nanoparticles on sand through green technology: Application for tetracycline

Ravikumar KVG, Debayan Ghosh, Mrudula Pulimi, Chandrasekaran Natarajan, Amitava Mukherjee

期刊论文

Zero E-waste: Regulatory impediments and blockchain imperatives

Mengjun Chen, Oladele A. Ogunseitan

期刊论文

Disinfection byproducts in drinking water and regulatory compliance: A critical review

Xiaomao WANG,Yuqin MAO,Shun TANG,Hongwei YANG,Yuefeng F. XIE

期刊论文

Liver cell therapies: cellular sources and grafting strategies

期刊论文

a novel anion exchange group modified hyper-crosslinked resin for the effective adsorption of both tetracycline

Qing ZHOU, Mengqiao WANG, Aimin LI, Chendong SHUANG, Mancheng ZHANG, Xiaohan LIU, Liuyan WU

期刊论文

METABOLIC AND TRANSCRIPTOME ANALYSIS REVEALS METABOLITE VARIATION AND FLAVONOID REGULATORY NETWORKS IN

期刊论文

Assessing combined toxic effects of tetracycline and P25 titanium dioxide nanoparticles using

Barsha Roy, Khushboo Kadam, Suresh Palamadai Krishnan, Chandrasekaran Natarajan, Amitava Mukherjee

期刊论文