Preparation of 5-fluorouracil-loaded Nanoparticles and Study of Interaction with Gastric Cancer Cells

Fan, Yu-Ling,Fan, Bing-Yu,Li, Qiang,Di, Hai-Xiao,Meng, Xiang-Yu,Ling, Na Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.18

Aims: To prepare 5-fluorouracil (5-Fu) nanoparticles with higher encapsulation efficiency and drug loading, and then investigate interaction with the SGC-7901 gastric cancer cell line. Materials and Methods: Prescription was optimized by orthogonal experiments, the encapsulation efficiency and loading capacity were tested by high-performance liquid chromatography, and inhibition of proliferation by 5-Fu nanoparticles and 5-Fu given to cells for 24, 48 and 72 hours was investigated by methyl thiazolyl tetrazolium assay (MTT). In addition, 5-Fu nanoparticles were labeled by fluorescein isothiocyanate (FITC), and absorption into cells was tested by flow cytometry. Results: The optimal conditions for preparation were concentrations of 5-Fu of 5mg/ml, of $CaCl_2$ of 60 mg/ml and of chitosan of 2 mg/ml. With a stirring speed of 1200rpm, encapsulation efficiency of 5-Fu nanoparticles was $55.4{\pm}1.10%$ and loading capacity was $4.22{\pm}0.14%$; gastric cancer cells were significantly inhibited by 5-Fu nanoparticles in a time and concentration dependent manner, and compared to 5-Fu with slower drug release, in a certain concentration range, inhibition with 5-Fu nanoparticles was stronger. 5-Fu nanoparticles were absorbed by the cells in line with the concentration. Conclusions: 5-Fu nanoparticles can inhibit growth of gastric cancer cells in vitro to a greater extent than with 5-Fu with good adsorption characteristics, supporting feasibility as a carrier.

Fire performance of edge and interior circular steel-reinforced concrete-filled steel tubular stub columns

Fan-Qin Meng,Mei-Chun Zhu,G. Charles Clifton,Kingsley U. Ukanwa,James B.P. Lim 국제구조공학회 2021 Steel and Composite Structures, An International J Vol.41 No.1

The steel-reinforced concrete-filled steel tubular column (SRCFT) is a new form of composite columns. Before widely accepted in engineering practice, its fire behaviour shall be fully understood. Four representative circular SRCFT stub columns were built and tested to failure under ISO fire herein. The tests explored the effect of reinforced steel, the internal or external heating condition and load ratios. The experimental results indicated that the inserted section steel significantly improved the fire resistance of circular SRCFT columns. The non-uniform fire condition did not produce a detrimental effect on the fire response of the specimen. The numerical model was developed and validated against the experimental results. Then a parametric study was present to evaluate the effect of load level, eccentricity and heating conditions. A comparison was made to check the accuracy of a widely accepted design method. The comparison indicated the design method was generally 36% conservative for axially loaded condition and 25% un-conservative for eccentrically loaded condition.

High-Performance Solution-Processed Non-Fullerene Organic Solar Cells Based on Selenophene-Containing Perylene Bisimide Acceptor

Meng, Dong,Sun, Dan,Zhong, Chengmei,Liu, Tao,Fan, Bingbing,Huo, Lijun,Li, Yan,Jiang, Wei,Choi, Hyosung,Kim, Taehyo,Kim, Jin Young,Sun, Yanming,Wang, Zhaohui,Heeger, Alan J. American Chemical Society 2016 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.138 No.1

<P>Non-fullerene acceptors have recently attracted tremendous interest because of their potential as alternatives to fullerene derivatives in bulk heterojunction organic solar cells. However, the power conversion efficiencies (PCEs) have lagged far behind those of the polymer/fullerene system, mainly because of the low fill factor (FF) and photocurrent. Here we report a novel perylene bisimide (PBI) acceptor, SdiPBI-Se, in which selenium atoms were introduced into the perylene core. With a well-established wide-band-gap polymer (PDBT-T1) as the donor, a high efficiency of 8.4% with an unprecedented high FF of 70.2% is achieved for solution-processed non-fullerene organic solar cells. Efficient photon absorption, high and balanced charge carrier mobility, and ultrafast charge generation processes in PDBT-T1:SdiPBI-Se films account for the high photovoltaic performance. Our results suggest that non-fullerene acceptors have enormous potential to rival or even surpass the performance of their fullerene counterparts.</P>

Heat-Shock Protein 70 as a Tumor Antigen for in vitro Dendritic Cell Pulsing in Renal Cell Carcinoma Cases

Meng, Fan-Dong,Sui, Cheng-Guang,Tian, Xin,Li, Yan,Yang, Chun-Ming,Ma, Ping,Liu, Yun-Peng,Jiang, You-Hong Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.20

Immunological functions of heat shock proteins (HSPs) have long been recognized. In this study we aimed to efficiently purify HSP70 from renal cell carcinoma and test it as a tumor antigen for pulsing dendritic cells in vitro. HSP70 was purified from renal cell carcinoma specimens by serial column chromatography on Con A-sepharose, PD-10, ADP-agarose and DEAE-cellulose, and finally subjected to fast protein liquid chromatography (FPLC). Dendritic cells derived from the adherent fraction of peripheral blood mononuclear cells were cultured in the presence of IL-4 and GM-CSF and exposed to tumor HSP70. After 24 hours, dendritic cells were phenotypically characterized by flow cytometry. T cells obtained from the non-adherent fraction of peripheral blood mononuclear cells were then co-cultured with HSP70-pulsed dendritic cells and after 3 days T cell cytotoxicity towards primary cultured renal cell carcinoma cells was examined by Cell Counting Kit-8 assay. Dendritic cells pulsed in vitro with tumor-derived HSP70 expressed higher levels of CD83, CD80, CD86 and HLA-DR maturation markers than those pulsed with tumor cell lysate and comparable to that of dendritic cells pulsed with tumor cell lysate plus TNF-${\alpha}$. Concomitantly, cytotoxic T-lymphocytes induced by HSP70-pulsed dendritic cells presented the highest cytotoxic activity. There were no significant differences when using homologous or autologous HSP70 as the tumor antigen. HSP70 can be efficiently purified by chromatography and induces in vitro dendritic cell maturation in the absence of TNF-${\alpha}$. Conspecific HSP70 may effectively be used as a tumor antigen to pulse dendritic cells in vitro.

Comparison of diapause and non-diapause induced Orius sauteri (Hemiptera: Anthocoridae) based on a two-sex life table in the laboratory

Meng Sun,Bing Lü,Zhao-yun Lyu,Yang Zhang,Yi-Fan Zhai,Hao Chen,Li Zheng,Yi Yu 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.4

The flower bug Orius sauteri (Poppius) is commonly used as an effective biocontrol agent for controlling small pest populations in greenhouses in China. The impact of two temperature and photoperiod regimes (26 °C, L16:D8 h; 21 °C, L8:D16 h) on the life table of O. sauteri was studied in the laboratory using an age-stage, two-sex life-table method. The results showed that the low-temperature short-photoperiod regime resulted in significant increases of the developmental times of the egg, the first to fifth nymphal stages, and the total preadult stage. Female adult longevity was significantly increased, whereas male adult longevity was significantly decreased, under this regime. Furthermore, the adult preoviposition period (APOP), the total preoviposition period (TPOP), and the sex ratio were all increased under this regime. Fecundity decreased, whereas the mean generation time (T) increased, as temperature and photoperiod decreased. The intrinsic rate of increase (r), finite rate of increase (λ), and net reproductive rate (Ro) all increased as the temperature decreased under diapause induction. Based on the estimated data, the higher r value (0.06 d−1) occurred under the 26 °C, L16:D8 h regime, compared with 0.03 d−1, under the 21 °C, L8:D16 h regime. Thus, the results showed that reproductive diapause slowed O. sauteri population growth, about 50% reduction based on r. There is significant interest in using O. sauteri as a biological control agent against non-diapausing small pests, such as thrips, in greenhouses under short photoperiods. However, based on the current results, managers should consider maintaining a high temperature and long photoperiod to prevent reproductive diapause induction in O. sauteri. Such conditions should not have a detrimental effect on the greenhouse crops

Vitexicarpin Induces Apoptosis in Human Prostate Carcinoma PC-3 Cells through G2/M Phase Arrest

Meng, Fan-Min,Yang, Jing-Bo,Yang, Chun-Hui,Jiang, Yu,Zhou, Yong-Feng,Yu, Bo,Yang, Hong Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.12

Vitexicarpin (3', 5-dihydroxy-3, 4', 6, 7-tetramethoxyflavone), a polymethoxyflavone isolated from Viticis Fructus (Vitex rotundifolia Linne fil.), has long been used as an anti-inflammatory herb in traditional Chinese medicine. It has also been reported that vitexicarpin can inhibit the growth of various cancer cells. However, there is no report elucidating its effect on human prostate carcinoma cells. The aim of the present study was to examine the apoptotic induction activity of vitexicarpin on PC-3 cells and molecular mechanisms involved. MTT studies showed that vitexicarpin dose-dependently inhibited growth of PC-3 cells with an $IC_{50}{\sim}28.8{\mu}M$. Hoechst 33258 staining further revealed that vitexicarpin induced apoptotic cell death. The effect of vitexicarpin on PC-3 cells apoptosis was tested using prodium iodide (PI)/Annexin V-FITC double staining and flow cytometry. The results indicated that vitexicarpin induction of apoptotic cell death in PC-3 cells was accompanied by cell cycle arrest in the G2/M phase. Furthermore, our study demonstrated that vitexicarpin induction of PC-3 cell apoptosis was associated with upregulation of the proapoptotic protein Bax, and downregulation of antiapoptotic protein Bcl-2, release of Cytochrome c from mitochondria and decrease in mitochondrial membrane potential. Our findings suggested that vitexicarpin may become a potential leading drug in the therapy of prostate carcinoma.

Mechanical Study on the Effect of Granular Friction in a Granular System under Biaxial Compression

Fan-Jing Meng,Kun Liu 한국물리학회 2018 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.72 No.10

The in uence of granular friction on the mechanical behaviors of a granular system is a typical research realm that is still not yet fully understood because of the complexities and the discreteness of the granular system. In this study, a two-dimensional model of a granular system with biaxial compression is established by using the discrete element method (DEM). Using this DEM model, we investigate the macroscopic mechanical behaviors, the microscopic mechanical responses and the force chain distributions of a granular system in uenced by granular friction. Simulation results show that the granular friction has a prominent in uence on the stress-strain response, dilatancy behaviors, and peak strength of the granular system. The microscopic mechanical behaviors of the coordination number, the sliding fraction, and the mean mobilized friction coecient of the granular system are also shown to be markedly in uenced by the granular friction. The force chains in the granular system form an inhomogeneous distribution, and their intensities increase with increasing granular friction.

폴리아스팔트아미드와 폴리(비닐 피롤리돈)의 상용블렌드 및 Semi-IPN 젤 제조

Fan Meng,전영실(Young Sil Jeon),정동준(Dong June Chung),김지흥(Ji Heung Kim) 한국고분자학회 2012 폴리머 Vol.36 No.5

폴리아스팔트아미드[α,β-poly(2-hydroxyethyl-DL-aspartamides), PHEAs]는 폴리아미노산의 일종으로서 잠재적인 의학 및 약학분야에 응용가능한 생분해성 생체적합성 재료로 널리 연구되어 왔다. 본 연구에서는 PHEA와 폴리(비닐 피롤리돈)(PNVP)의 블렌드 및 semi-IPN 젤에 관하여 다루었다. 블렌드 필름은 용액 캐스팅법으로 제조되었다. 제조된 블렌드는 전 조성에서 투명하였으며 DSC를 통해 조성에 따라 단조롭게 변화하는 단일한 유리전이 온도가 관찰됨으로써 두 개 고분자가 서로 상용성이 있음을 확인하였다. 고분자간의 가능한 수소결합 상호작용을 FTIR을 이용하여 설명하였다. 한편, 일정 조성의 PHEA/PNVP 블렌드 용액을 핵사메틸렌디이소시아네이트(HMDI)를 가교제로 사용하여 semi-IPN 타입의 하이브리드 젤을 제조하고, 제조된 젤의 팽윤 물성과 모폴로지를 조사하였다. PHEAs [α,β-poly(2-hydroxyethyl-DL-aspartamides)], a class of poly(amino acid), have been widely studied as biodegradable and biocompatible polymers for potential biomedical and pharmaceutical applications. In this study, we investigated a homogeneous blend of PHEA with poly(N-vinyl pyrrolidone) (PNVP) and its semi-IPN (semi-interpenetrating polymer network) gels. Blend films were prepared by a solution casting method. The resulting blends were totally transparent over the whole composition ranges and the single Tg, changing monotonously with composition, was observed by DSC to confirm the miscibility between these two polymers. FTIR was used to discuss the possible hydrogen-bonding interaction between polymers. In addition, semi-IPN type gels were prepared by chemical crosslinking of PHEA/PNVP blend solution using hexamethylene diisocyanate (HMDI) as a crosslinking reagent. The prepared gel was characterized by their swelling property and morphology.

A comprehensive evaluation method study for dam safety

Fan Jia,Meng Yang,Bingrui Liu,Jianlei Wang,Jiaorong Gao,Huaizhi Su,Erfeng Zhao 국제구조공학회 2017 Structural Engineering and Mechanics, An Int'l Jou Vol.63 No.5

According to the multi-index system of dam safety assessment and the standard of safety, a comprehensive evaluation model for dam safety based on a cloud model is established to determine the basic probability assignment of the Dempster-Shafer theory. The Dempster-Shafer theory is improved to solve the high conflict problems via fusion calculation. Compared with the traditional Dempster-Shafer theory, the application is more extensive and the result is more reasonable. The uncertainty model of dam safety multi-index comprehensive evaluation is applied according to the two theories above. The rationality and feasibility of the model are verified through application to the safety evaluation of a practical arch dam.

Synthesis of multi-walled carbon nanotubes over tungsten-doped cobalt-based catalyst derived from a layered double hydroxide precursor

Meng Lan,Feng Li,Guoli Fan,Qilong Chen 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.4

Multi-walled carbon nanotubes (CNTs) were prepared over a series of W-doped Co-based catalysts derived from layered double hydroxide precursor by catalytic chemical vapor deposition (CCVD) of acetylene. The materials were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption–desorption experi-ments and Raman spectroscopy. The effect of the proportion of W in the Co-based catalysts on the carbon yield, diameter uniformity and quality of CNTs was investigated. The results demonstrated that with the increasing W/Co molar ratio from 0 to 1.0, both the mean number of walls and the average diameter of CNT produced over catalysts increased from about 8 to 28 nm and from about 12.1 to 23.7 nm, respectively. A small amount of tungsten added to the catalyst with the W/Co molar ratio of 0.3 could facilitate the dispersion of catalytically active Co species on the surface of support, and thus uniform and high-quality CNTs with a remarkably high yield of ca. 1600% were obtained.