Synthesis of Polymeric Phthalocyanine Sulfonate Photosensitizer and Its Photodegradation on Rhodamine B in Aqueous Medium

Peng Zhao,우재완,박용성,Yenan Song,Fushi Zhang 한국고분자학회 2010 Macromolecular Research Vol.18 No.5

Novel phthalocyanine sulfonate (H2PPcSx) was synthesized from the sulfonation of a steric polymeric phthalocyanine and investigated as a photocatalyst in a homogenous system. The molecular weight of H2PPcSx was characterized as 9213-11692 by MALDI-TOF MS, classified as an oligomer with a 14-18 degree of polymerization. The electronic spectrum indicated a less aggregative tendency of H2PPCSx than the usual monomeric phthalocyanine photocatalyst. Efficient photodegradation of butyl Rhodamine B (bu Rh B) catalyzed by H2PPcSx was achieved in a homogenous solution; the spectral character indicated that decomposition occurred on the benzene ring in the Rh B molecular. For a 50 mg L-1 bu Rh B solution, the percentage degradation reached 95% in 4 h using 100 mg H2PPcSx as a photocatalyst. A mechanism involving the participation of both singlet oxygen and radicals was established for the photodegradation.

First-principles study of the switching characteristics of the 15,16-dinitrile DDP/CPD-based optical molecular switch with carbon nanotube electrodes

Peng Zhao,Chang-feng Fang,Yi-ming Wang,Ya-xi Zhai,De-sheng Liu 한국물리학회 2009 Current Applied Physics Vol.9 No.6

We have studied the switching characteristics of an optical molecular switch based on the 15,16-dinitrile dihydropyrene/cyclophanediene (DDP/CPD) molecule with two single-walled carbon nanotube (SWCNT) electrodes using first-principles transport calculations. It is shown that the DDP shows an overall higher conductance than the CPD at low bias which is independently of the SWCNT chirality. Meantime, the conductance of the molecular switch can be tuned by the chirality of the SWCNT. We have studied the switching characteristics of an optical molecular switch based on the 15,16-dinitrile dihydropyrene/cyclophanediene (DDP/CPD) molecule with two single-walled carbon nanotube (SWCNT) electrodes using first-principles transport calculations. It is shown that the DDP shows an overall higher conductance than the CPD at low bias which is independently of the SWCNT chirality. Meantime, the conductance of the molecular switch can be tuned by the chirality of the SWCNT.

Anti-tumor effect of novel amino acid Schiff base nickel (II) complexes on oral squamous cell carcinoma cells (CAL-27) in vitro

Zhao Peng,Qiu Haiming,Wei Qiang,Li Yang,Gao Lei,Zhao Peiran 대한독성 유전단백체 학회 2023 Molecular & cellular toxicology Vol.19 No.2

Background Oral squamous cell carcinoma (OSCC) is a common skin/oral malignant tumor. In recent years, advancements in the fi eld of medical technology resulted in signifi cant improvement in the treatment and management of OSCC. However, adverse reactions associated with the application of radiotherapy and chemotherapeutic drugs resulted in a low overall survival rate. Therefore, it is important to develop and explore alternative chemotherapy drugs, which can eff ectively treat OSCC, and clarify their mechanism of action. Objective The present study aimed to investigate the eff ect of three hexa-coordinated octahedral nickel (II) complexes, namely [Ni(sal- L -phe)(phen)(CH 3 OH)] CH 3 OH ( 1 ), [Ni(naph- L -phe)(phen)(CH 3 OH)] ( 2 ), and [Ni( o -van- L -phe)(phen) (CH 3 OH)] 5CH 3 OH ( 3 ), on proliferation, migration, and apoptosis of CAL-27 cells. Results The results of the study showed that complex 3 exhibited sensitive/signifi cant cytotoxicity toward CAL-27 cells, with an IC 50 value of 15.90 mΜ. Further, an assessment of the underlying mechanism showed that complex 3 could signifi cantly increase autophagy and reactive oxygen species (ROS) levels in CAL-27 cells. At the same time, it reduced mitochondrial membrane potential (MMP) in a dose-dependent manner. Additionally, complex 3 might act via inhibition of proliferation and migration of CAL 27 cells and induction of apoptosis, which was mediated via regulation of the expression of Bcl-2 family proteins in vitro. Conclusion The results of the study showed that nickel complexes could potently inhibit the growth of CAL-27 cells, which was mediated via mitochondrial dysfunction, intracellular ROS accumulation, and ROS-mediated DNA damage. Altogether, the fi ndings of the study would provide new leads for the designing and synthesis of novel metal drugs for OSCC.

Anti-proliferation Effects of Interferon-gamma on Gastric Cancer Cells

Zhao, Ying-Hui,Wang, Tao,Yu, Guang-Fu,Zhuang, Dong-Ming,Zhang, Zhong,Zhang, Hong-Xin,Zhao, Da-Peng,Yu, Ai-Lian Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.9

IFN-${\gamma}$ plays an indirect anti-cancer role through the immune system but may have direct negative effects on cancer cells. It regulates the viability of gastric cancer cells, so we examined whether it affects their proliferation and how that might be brought about. We exposed AGS, HGC-27 and GES-1 gastric cancer cell lines to IFN-${\gamma}$ and found significantly reduced colony formation ability. Flow cytometry revealed no effect of IFN-${\gamma}$ on apoptosis of cell lines and no effect on cell aging as assessed by ${\beta}$-gal staining. Microarray assay revealed that IFN-${\gamma}$ changed the mRNA expression of genes related to the cell cycle and cell proliferation and migration, as well as chemokines and chemokine receptors, and immunity-related genes. Finally, flow cytometry revealed that IFN-${\gamma}$ arrested the cells in the G1/S phase. IFN-${\gamma}$ may slow proliferation of some gastric cancer cells by affecting the cell cycle to play a negative role in the development of gastric cancer.

Research on Peak-detection Algorithm for High-precision Demodulation System of Fiber Bragg Grating

Peng Wang,Xu Han,Simin Guan,Hong Zhao,Minglei Shao 보안공학연구지원센터 2014 International Journal of Hybrid Information Techno Vol.7 No.6

In order to improve the detection accuracy of wavelength, the filtering and curve fitting technologies were applied in the FBG wavelength demodulation system based on tunable F-P filter. These methods could realize the accurate peak-location of output signals of the photo detector. According to the characteristics of noise, the FIR low-pass filter was designed to filter the obtained light power signals so as to provide the input signals with high SNR for the peak-detection algorithms. By analyzing and comparing several typical peak-searching algorithms, the algorithm of Gauss formula nonlinear curve fitting (L-M) was chosen to fit the digitized light power signals. The experimental results show that L-M fitting algorithm reduces the mean square error by 7.5% compared with the Gauss fitting algorithm. For the Gauss signal in the wavelength demodulation system designed in the paper, the L-M algorithm has lower mean square error than other peak-searching algorithms. This algorithm is suitable for FBG wavelength demodulation system based on tunable F-P filter. It can efficiently raise the accuracy of wavelength demodulation system.

온도에 의한 황산적늑대거미(거미목: 늑대거미과)의 성장과 생식에 관한 연구

Peng Y.J.Z.Zhao,J.P.Kim 외1명 한국거미연구소 1998 한국거미 Vol.14 No.2

Opportunistic Routing for Bandwidth-Sensitive Traffic in Wireless Networks with Lossy Links

Zhao, Peng,Yang, Xinyu The Korea Institute of Information and Commucation 2016 Journal of communications and networks Vol.18 No.5

Opportunistic routing (OR) has been proposed as a viable approach to improve the performance of wireless multihop networks with lossy links. However, the exponential growth of the bandwidth-sensitive mobile traffic (e.g., mobile video streaming and online gaming) poses a great challenge to the performance of OR in term of bandwidth guarantee. To solve this problem, a novel mechanism is proposed to opportunistically forwarding data packets and provide bandwidth guarantee for the bandwidth-sensitive traffic. The proposal exploits the broadcast characteristic of wireless transmission and reduces the negative effect of wireless lossy links. First, the expected available bandwidth (EAB) and the expected transmission cost (ETC) under OR are estimated based on the local available bandwidth, link delivery probability, forwarding candidates, and prioritization policy. Then, the policies for determining and prioritizing the forwarding candidates is devised by considering the bandwidth and transmission cost. Finally, bandwidth-aware routing algorithm is proposed to opportunistically delivery data packets; meanwhile, admission control is applied to admit or reject traffic flows for bandwidth guarantee. Extensive simulation results show that our proposal consistently outperforms other existing opportunistic routing schemes in providing performance guarantee.

Realgar transforming solution suppresses angiogenesis and tumor growth by inhibiting VEGF receptor 2 signaling in vein endothelial cells

Peng Song,Yang Hai,Xin Wang,Longhe Zhao,Baoqiang Chen,Peng Cui,Qin-Jian Xie,Lan Yu,Yang Li,Zhengrong Wu,Hong Yu Li 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.4

Realgar (As4S4), as an arsenic sulfide mineraldrug, has a good therapeutic reputation for anticancer inTraditional Chinese Medicine, and has recently beenreported to inhibit angiogenesis in tumor growth. However,considering the poor solubility and low bioavailability ofrealgar, large dose of realgar and long period of treatmentare necessary for achieving the effective blood medicineconcentration. In present study, we resolved the crucialproblem of poor solubility of realgar by using intrinsicbiotransformation in microorganism, and investigatedunderlying mechanisms of realgar transforming solution(RTS) for antiangiogenesis. Our results demonstrated thatRTS had a strong activity to inhibit HUVECs proliferation,migration, invasion, and tube formation. Moreover, RTSinhibited VEGF/bFGF-induced phosphorylation ofVEGFR2 and the downstream protein kinases includingERK, FAK, and Src. In vivo zebrafish and chickenchorioallantoic membrane model experiments showed thatRTS remarkably blocked angiogenesis. Finally, comparedwith the control, administration of 2.50 mg/kg RTSreached more than 50% inhibition against H22 tumorallografts in KM mice, but caused few toxic effects in thehost. The antiangiogenic effect was indicated by CD31immunohistochemical staining and alginate-encapsulatedtumor cell assay. In summary, our findings suggest thatRTS inhibits angiogenesis and may be a potential drugcandidate in anticancer therapy.

Opportunistic Routing for Bandwidth-Sensitive Traffic in Wireless Networks with Lossy Links

Peng Zhao,Xinyu Yang 한국통신학회 2016 Journal of communications and networks Vol.18 No.5

Opportunistic routing (OR) has been proposed as a vi-able approach to improve the performance of wireless multihopnetworks with lossy links. However, the exponential growth ofthe bandwidth-sensitivemobile traffic (e.g.,mobile video streamingand online gaming) poses a great challenge to the performance ofOR in term of bandwidth guarantee. To solve this problem, a novelmechanism is proposed to opportunistically forwarding data pack-ets and provide bandwidth guarantee for the bandwidth-sensitivetraffic. The proposal exploits the broadcast characteristic of wire-less transmission and reduces the negative effect of wireless lossylinks. First, the expected available bandwidth (EAB) and the ex-pected transmission cost (ETC) under OR are estimated basedon the local available bandwidth, link delivery probability, for-warding candidates, and prioritization policy. Then, the policiesfor determining and prioritizing the forwarding candidates is de-vised by considering the bandwidth and transmission cost. Finally,bandwidth-aware routing algorithm is proposed to opportunisti-cally delivery data packets; meanwhile, admission control is ap-plied to admit or reject traffic flows for bandwidth guarantee. Ex-tensive simulation results show that our proposal consistently out-performs other existing opportunistic routing schemes in providingperformance guarantee.

The evolution of the Pyongnam basin: Its relationship with the adjacent basins and tectonic implications

Peng Peng,Mingguo Zhai,Jong-Hyok Yang,Chang-Whan Oh,Hyon-Uk Pak,Yanbin Zhang,Lei Zhao,Zhiyue Zhang,Fengbo Sun 대한지질학회 2019 대한지질학회 학술대회 Vol.2019 No.10