Targeting treatment of bladder cancer using PTK7 aptamer-gemcitabine conjugate

Xiang Wei,Peng Yongbo,Zeng Hongliang,Yu Chunping,Zhang Qun,Liu Biao,Liu Jiahao,Hu Xing,Wei Wensu,Deng Minhua,Wang Ning,Liu Xuewen,Xie Jianfei,Hou Weibin,Tang Jin,Long Zhi,Wang Long,Liu Jianye 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Gemcitabine (GEM) is one of the first-line chemotherapies for bladder cancer (BC), but the GEMs cannot recognize cancer cells and have a low long-term response rate and high recurrence rate with side effects during the treatment of BC. Targeted transport of GEMs to mediate cytotoxicity to tumor and avoid the systemic side effects remains a challenge in the treatment of BC.Based on a firstly confirmed biomarker in BC-protein tyrosine kinase 7 (PTK7), which is overexpressed on the cell membrane surface in BC cells, a novel targeting system protein tyrosine kinase 7 aptamer-Gemcitabine conjugate (PTK7-GEMs) was designed and synthesized using a specific PTK7 aptamer and GEM through auto-synthesis method to deliver GEM against BC. In addition, the antitumor effects and safety evaluation of PTK7-GEMs was assessed with a series of in vitro and in vivo assays.PTK7-GEMs can specifically bind and enter to BC cells dependent on the expression levels of PTK7 and via the macropinocytosis pathway, which induced cytotoxicity after GEM cleavage from PTK7-GEMs respond to the intracellular phosphatase. Moreover, PTK7-GEMs showed stronger anti-tumor efficacy and excellent biosafety in three types of tumor xenograft mice models.These results demonstrated that PTK7-GEMs is a successful targeted aptamer-drug conjugates strategy (APDCs) to treat BC, which will provide new directions for the precision treatment of BC in the field of biomarker-oriented tumor targeted therapy.

Study on the strengthening mechanisms of Cu/CNT nano-composites

Long, Xiang,Bai, Yuanli,Algarni, Mohammed,Choi, Youngsik,Chen, Quanfang Elsevier 2015 Materials science & engineering. properties, micro Vol.645 No.-

<P><B>Abstract</B></P> <P>Recent experimental studies by Chen et al. showed that copper (Cu) matrix reinforced by a small amount of carbon nanotubes (CNT, about 4% volume fraction) will increase material strength by about 300% while sacrificing some material ductility. The strengthening mechanisms of Cu/CNT nano-composites were firstly studied numerically using 2D axial symmetric unit cell finite element (FE) models in Ls-Dyna, which consist of both copper matrix and CNTs. The simulation results were verified by existing experimental data. A round of parametric studies was performed to investigate the effects of several modeling parameters in the FE simulations. These parameters include the volume fraction of CNTs, aspect ratio of CNTs, size of hardening zone, and the “equivalent” hardened plastic strain in the hardened zone. Two main strengthening mechanisms are found that affect CNTs reinforcement prediction. The first one is the load-bearing effect resulting from boundary condition imposed in the models. The CNTs significantly affect the plastic flow of copper around CNTs during plastic deformation, which is one important reinforcement mechanism because of high aspect ratio ( H / D ) of CNTs. The second strengthening mechanism is found to be the hardened zone of Cu matrix around CNTs, which is introduced by manufacturing processes and/or the Orowan effect. The Orowan effect plays a key role in reinforcement especially in the nano-scale, which results in a very small inter-particle spacing. The Orowan effect was also studied using analytical methods. Both analytical solution and unit cell FE modeling well correlated with the experimental results for various Cu/CNT composites with different CNT outside diameters.</P>

Removal of nitric oxide and sulfur dioxide from flue gases using a FeII-ethylenediamineteraacetate solution

Xiang-li Long,Hai-Song Zhu,Yan-Peng Mao,Yu Chen,Wei-kang Yuan 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.6

The combined absorption of NO and SO2 into the Fe(II)-ethylenediamineteraacetate(EDTA) solution has been realized. Activated carbon is used to catalyze the reduction of FeIII-EDTA to FeII-EDTA to maintain the ability to remove NO with the Fe-EDTA solution. The reductant is the sulfite/bisulfite ions produced by SO2 dissolved into the aqueous solution. Experiments have been performed to determine the effects of activated carbon of coconut shell,pH value, temperature of absorption and regeneration, O2 partial pressure, sulfite/bisulfite and chloride concentration on the combined elimination of NO and SO2 with FeII-EDTA solution coupled with the FeII-EDTA regeneration catalyzed by activated carbon. The experimental results indicate that NO removal efficiency increases with activated carbon mass. There is an optimum pH of 7.5 for this process. The NO removal efficiency increases with the liquid flow rate but it is not necessary to increase the liquid flow rate beyond 25 ml min−1. The NO removal efficiency decreases with the absorption temperature as the temperature is over 35 oC. The Fe2+ regeneration rate may be speeded up with temperature. The NO removal efficiency decreases with O2 partial pressure in the gas streams. The NO removal efficiency is enhanced with the sulfite/bisulfite concentration. Chloride does not affect the NO removal. Ca(OH)2 and MgO slurries have little influence on NO removal. High NO and SO2 removal efficiencies can be maintained at a high level for a long period of time with this heterogeneous catalytic process.

Effect of bio-template on the properties of SiO2/Al2O3 composites for drug delivery

Long-Yue Meng,Weiqi Jiang,Wen Xiang Piao,Wan Meng 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.37 No.-

In this study, SiO2/Al2O3 composites (C-SLNs) were successfully synthesized using chitosan as thetemplate for drug delivery. The C-SLNs had higher specific surface areas (244–607 m2/g), total porevolumes (0.19–0.34 cm3 g 1), and narrow mesopore size distribution. The porosity of the C-SLNsprepared under high Si/Al ratio conditions was achieved mostly by the formation of wider pores thatwere distributed in the meso-/macro-pores. And, the C-SLNs were used as a levofloxacin carrier to studyits drug release behavior, which exhibited an initial fast release followed by a sustained release andantibacterial effectiveness over a long period.

Production of isophthalic acid from m-xylene oxidation under the catalysis of the H3PW12O40/carbon and cobalt catalytic system

Xiang-li Long,Zhi-hao Wang,San-qiang Wu,Shi-ming Wu,Hai-feng Lv,Wei-kang Yuan 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.1

Isophthalic acid (IPA) is commercially produced from m-xylene oxidation with the catalysis of thehomogeneous Co–Mn–Br catalyst system. In this study, a catalytic system consisting of HPW/C and Co(II)has been put forward to oxidize m-xylene (MX) to IPA. The experimental results prove that the HPW/Cand Co catalytic system is capable of catalyzing the oxidation of MX to IPA, which can obtain a higher MXconversion and IPA concentration than the homogeneous H3PW12O40/Co(OAc)2/Mn(OAc)2 catalyticsystem. The heterogeneous catalytic system is also advantageous over the homogeneous catalyticsystem in the inhibition of the oxidation of acetic acid and IPA. The optimal amount of phosphotungsticacid supported on carbon is 7.5% (wt). The best dosage of HPW/C is 15 g l-1. The optimum Co(II)concentration in the catalytic system for IPA production is 0.064% (wt). The best HPW/C activationtemperature is 220℃ .

Diabetes Mellitus and Prostate Cancer Risk in Asian Countries: a Meta-analysis

Long, Xiang-Ju,Lin, Shan,Sun, Ya-Nan,Zheng, Zhen-Feng Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.8

Background/Aims: Diabetes mellitus (DM) is widely considered to be associated with risk of cancer, but studies investigating the association between DM and prostate cancer in Asian countries have reported inconsistent findings. We examined this association by conducting a detailed meta-analysis of studies published on the subject. Methods: Cohort or case-control studies were identified by searching Pubmed, Embase and Wanfang databases through May 30, 2012. Pooled relative risk (RR) with its corresponding 95% confidence interval (95% CI) were calculated using the random-effects model. Subgroup analyses were performed by the study type. Results: Finally, we identified 7 studies (four cohort studies and three case-control studies) with a total of 1,751,274 subjects from Asians. DM was associated with an increased risk of prostate cancer in Asians (unadjusted RR= 2.82, 95% CI 1.73.4.58, P < 0.001; adjusted RR= 1.31, 95% CI 1.12.1.54, P = 0.001). Subgroup analyses by study design further confirmed an obvious association. Conclusion: Findings from this meta-analysis strongly support that diabetes is associated with an increased risk of prostate cancer in Asians.

Removal of NO with the hexamminecobalt(II) solution catalyzed by the activated carbon treated with acetic acid

Xiang-li Long,Bei-bei Duan,Hai-xia Cao,Ming-lei Jia,Long-an Wu 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.62 No.-

The simultaneous scrubbing of NO and SO2 can be finished with the Co(NH3)62+ ammonia solution. Activated carbon aids the regeneration of Co(NH3)62+ to retain the ability of absorbing NO. Acetic acid is tried to improve the catalytic capability of activated carbon. The best treatment condition is the carbon samples impregnated in 2.0 mol l−1 HAc solution for 20 h followed by being calcined at 600 °C for 4 h. The HAc modification increases surface area and acidic groups on the carbon surface. The experiments prove that the modified carbon can obtain a higher NO removal efficiency than the original carbon.

Suppression of CDK2 expression by siRNA induces cell cycle arrest and cell proliferation inhibition in human cancer cells

( Xiang E Long ),( Zhao Hui Gong ),( Lin Pan ),( Zhi Wei Zhong ),( Yan Ping Le ),( Qiong Liu ),( Jun Ming Guo ),( Jiu Chang Zhong ) 한국생화학분자생물학회 (구 한국생화학회) 2010 BMB Reports Vol.43 No.4

Cyclin-dependent kinase 2 (CDK2) is a member of serine/threonine protein kinases, which initiates the principal transitions of the eukaryotic cell cycle and is a promising target for cancer therapy. The present study was designed to inhibit cdk2 gene expression to induce cell cycle arrest and cell proliferation suppression. Here, we constructed a series of RNA interference (RNAi) plasmids which can successfully express small interference RNA (siRNA) in the transfected human cells. The results showed that the RNAi plasmids containing the coding sequences for siRNAs down-regulated the cdk2 gene expression in human cancer cells at the mRNA and the protein levels. Furthermore, we found that the cell cycle was arrested at G0G1 phases and the cell proliferation was inhibited by different siRNAs. These results demonstrate that suppression of CDK2 activity by RNAi may be an effective strategy for gene therapy in human cancers. [BMB reports 2010; 43(4): 291-296]

Regulation of Metabolic Flux in Lactobacillus casei for Lactic Acid Production by Overexpressed LdhL Gene with Two-Stage Oxygen Supply Strategy

( Xiang Yang Ge ),( Yan Xu ),( Xiang Chen ),( Long Yun Zhang ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.1

This study describes a novel strategy to regulate the metabolic flux for lactic acid production in Lactobacillus casei. The ldhL gene encoding L-lactate dehydrogenase (L-LDH) was overexpressed in L. casei, and a two-stage oxygen supply strategy (TOS) that maintained a medium oxygen supply level during the early fermentation phase, and a low oxygen supply level in the later phase was carried out. As a consequence, a maximum L-LDH activity of 95.6 U/ml was obtained in the recombinant strain, which was over 4-fold higher than that of the initial strain. Under the TOS for L. casei (pMG-ldhL), the maximum lactic acid concentration of 159.6 g/l was obtained in 36 h, corresponding to a 62.8% increase. The results presented here provide a novel way to regulate the metabolic flux of L. casei for lactic acid production in different fermentation stages, which is available to enhance organic acid production in other strains.

Non-interest Income, Profit, and Risk Efficiencies: Evidence from Commercial Banks in China

Wen-Long Bian,Xiang-Nan Wang,Qi-Xiang Sun 한국증권학회 2015 Asia-Pacific Journal of Financial Studies Vol.44 No.5

Chinese commercial banks are transforming their activities into more non-interest income businesses under a highly regulated financial system. This paper investigates the effects of this transformation on profit and risk efficiencies. We find that commission and fee income sig- nificantly reduce risk efficiency due to the circumvention of the regulation on deposit interest rate and the assumption of risk that should have been borne by customers. In terms of trad- ing income, it significantly reduces profit efficiency due to the upper limit of the loan-deposit ratio, the lack of investment channels and low returns of bond markets. The regulatory authorities are supposed to further liberalize the banking industry and grant banks more rights.