Post-Process Modification of CeOx/C-Supported PtCu Thin Film Catalyst and Its Catalytic Activity for Hydrogen Evolution Reaction

Yumeng Zhao,Bin Yang,Xinyu Hao,Zhijing Zhao 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2015 NANO Vol.10 No.6

CeOx/C supported PtCu thin film catalysts were prepared by ion beam sputtering (IBS) and subsequently annealed at 400℃ under vacuum environment and electrochemically dealloyed. Scanning transmission electronic microscope (STEM) and atomic force microscope (AFM) characterizations show that the surface of post-processed catalyst presents nanoporous structure and has a high root mean square roughness ( RMS=13.9 nm). Electrochemical measurements indicate that the post-processed PtCu – CeOx/C catalyst shows higher catalytic activity towards hydrogen evolution reaction than pure Pt/C. While inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis displays that the platinum (Pt) loading of the post-processed PtCu – CeOx/C is 0.1192 mg/cm2, decreasing by 20% compare to pure Pt/C (0.1490 mg/cm2). X-ray photoelectron spectroscopy (XPS) analysis confirms that the surface of post-processed PtCu – CeOx/C enrich Pt and analyzes the chemical valence of Pt element using depth profiling technology. It can be inferred that the enhancement in catalytic property is attributed to the combined action between geometric structure effect and electronic modification effect of Pt atoms from CeOx support.

Paclitaxel targeting to lungs by way of liposomes prepared by the effervescent dispersion technique

Yumeng Wei,Zhengkai Xue,Yun Ye,Yu Huang,Ling Zhao 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.6

In order to develop a novel lung targeting drugdelivery system (LTDDS) with large-sized liposomescontaining paclitaxel (PTX), the liposomes composed ofPTX, phosopholipon 90H and tween-80 were prepared bythe effervescent dispersion technique with optimal formulationcomposition. The liposomes were found to be relativelyuniform in particle size (8.166 ± 0.459 lm) with anegative zeta-potential (-12.45 ± 1.34 mv), and highentrapment efficiency (92.20 ± 2.56 %). They kept stablefor at least 3 months and exhibited a slow release behaviorwithout any hemolysis reaction. Via intravenous administrationin rabbits, the PTX liposomes presented a longermean residence time and elimination half-life, and a muchlarger area under the plasma drug concentration–time curvecompared with its injection; meanwhile, the liposomesaltered its biodistribution and exhibited a significant lungtargeting characteristic. For example, the relative intakerate (Re) and the ratio of peak concentration (Ce) of lungwere 14.87 and 26.44, respectively. Compared with heart,liver, spleen and kidney, the ratios of targeting efficacy(Te)liposomes to (Te)injection of lung were increased by afactor of 20.08, 11.10, 6.97 and 14.41, respectively. To sum up, the liposome could be a promising drug carrier forPTX as LTDDS for lung cancer treatment.

The combination of curcumin and 5-fluorouracil in cancer therapy

Yumeng Wei,Panjing Yang,Shousong Cao,Ling Zhao 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.1

5-Fluorouracil (5-FU) alone or in combinationwith other therapeutic drugs has been widely used forclinical treatment of various cancers. However, 5-FU-basedchemotherapy has limited anticancer efficacy in clinic dueto multidrug resistance and dose-limiting cytotoxicity. Some molecules and genes in cancer cells, such as nuclearfactor kappa B, insulin-like growth factor-1 receptor, epidermalgrowth factor receptor, cyclooxygenase-2, signaltransducer and activator of transcription 3, phosphatase andtensin homolog deleted on chromosome ten and Bcl-2 etc. are related to the chemoresistance and sensitivity of cancercells to 5-FU. The activation of these molecules and genesexpressions in cancer cells will be increased or decreasedwith long-term exposure of 5-FU. Curcumin has beenfound to be able to negatively regulate these processes. Inorder to overcome the problems of 5-FU, curcumin hasbeen used to combine with 5-FU in cancer therapy.

TGF-β promotes pericyte-myofibroblast transition in subretinal fibrosis through the Smad2/3 and Akt/mTOR pathways

Zhao Zhenzhen,Zhang Yumeng,Zhang Chaoyang,Zhang Jingting,Luo Xueting,Qiu Qinghua,Luo Dawei,Zhang Jingfa 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Subretinal fibrosis remains a major obstacle to the management of neovascular age-related macular degeneration. Choroidal pericytes were found to be a significant source of subretinal fibrosis, but the underlying mechanisms of pericyte-myofibroblast transition (PMT) remain largely unknown. The goal of this study was to explore the role and potential mechanisms by which PMT contributes to subretinal fibrosis. Choroidal neovascularization (CNV) was induced by laser photocoagulation in transgenic mice with the collagen1α1-green fluorescent protein (Col1α1-GFP) reporter, and recombinant adeno-associated virus 2 (rAAV2)-mediated TGF-β2 (rAAV2-TGF-β2) was administered intravitreally to further induce PMT. Primary mouse choroidal GFP-positive pericytes were treated with TGF-β2 in combination with siRNAs targeting Smad2/3, the Akt inhibitor MK2206 or the mTOR inhibitor rapamycin to examine cell proliferation, migration, and differentiation into myofibroblasts. The involvement of the Akt/mTOR pathway in PMT in subretinal fibrosis was further investigated in vivo. Intraocular TGF-β2 overexpression induced GFP-positive pericyte infiltration and PMT in subretinal fibrosis, which was mimicked in vitro. Knockdown of Smad2/3 or inhibition of Akt/mTOR decreased cell proliferation, PMT and migration in primary mouse pericytes. Combined inhibition of Smad2/3 and mTOR showed synergistic effects on attenuating α-smooth muscle actin (α-SMA) expression and cell proliferation. In mice with laser-induced CNV, the administration of the Akt/mTOR inhibitors suppressed pericyte proliferation and alleviated the severity of subretinal fibrosis. Our results showed that PMT plays a pivotal role in subretinal fibrosis, which was induced by TGF-β2 through the Smad2/3 and Akt/mTOR pathways. Thus, inhibiting PMT may be a novel strategy for the treatment of subretinal fibrosis.

Formulation and pharmacokinetic evaluation of once-daily sustained-released system of nifedipine with solid dispersion and coating techniques

Yumeng Wei,Zhengkai Xue,Peng Wang,Ling Zhao 대한약학회 2013 Archives of Pharmacal Research Vol.36 No.7

A novel sustained-release system was developedfor poorly water-soluble drugs by applying soliddispersion (SD) technique to improve the solubility. TheSD systems composed of polyvinyl pyrrolidone and stearicacid could not control the release of nifedipine. When theabove SD granules were coated with ethylcellolulose(EC10, 45 and 100cp), the dissolution rate extended from16 to 20 h. When the concentration of EC100cp wasincreased to 4–6 %, the sustained-release formulation F7and F8 prepared with 4 % EC100cp and 6 % EC100cp,respectively, could control the drug release in a bettermanner, namely, they could control drug release in theinitial hours with a high cumulative amount of drug at24 h. The mechanism of drug release from F7 and F8 wasdiffusion coupled with erosion. When immediate-releasecapsules was orally administered to rabbits, its absorptionwas very rapid with a short elimination half-life, while aprolonged maintenance of the plasma drug level up to 24 hwas obtained for F7 and F8. Furthermore, the oral bioavailabilityof F7 and F8 was significantly improved. Theresults suggested that this novel sustained-release systemwould be a promising system to improve the solubility andsustain the absorption of poorly water-soluble drugs.

Distribution of pathological types and epidemiological characteristics based on kidney biopsy in Northwest China

Qin Yunlong,Zhao Jin,Wei Xiao-fei,Wang Yuwei,Yu Zixian,Zhang Yumeng,Sun Shiren 대한신장학회 2023 Kidney Research and Clinical Practice Vol.42 No.1

Background: The spectrum of biopsy-confirmed kidney disease varies with regions and periods. We describe the distribution ofpathological types and epidemiological characteristics of kidney diseases in Northwest China due to regional differences in geographicalenvironment, social economy, and dietary habits.Methods: Kidney biopsy cases from 2005 to 2020 in Xijing Hospital were retrospectively analyzed. Pathological characteristics of patientsin different periods were analyzed using the t test or chi-square test. Joinpoint regression was used to analyze trends in pathologicaltypes and disease spectrum.Results: A total of 10,528 eligible patients were included. Primary glomerular disease (PGD) accounted for the majority of the casesand exhibited an obvious downward trend, whereas secondary glomerular disease (SGD) showed an obvious upward trend. AmongPGD, immunoglobulin A nephropathy (IgAN) remained the most common pathological type, and the detection rate of membranousnephropathy (MN) was significantly increased. Among SGD, Henoch-Schönlein purpura nephritis (HSPN) was the most commonpathological type and may present a significant characteristic of Northwest China. Diabetic nephropathy (DN) exhibited the most obviousupward trend in the whole process, whereas the fastest growth since 2012 was in hypertensive nephropathy.Conclusion: The proportion of SGD increased whereas PGD declined. IgAN remained the most common PGD, and HSPN was themost common SGD. MN and DN showed the most obvious upward trend among PGD and SGD, respectively. Changes in the spectrumof kidney disease, especially the constituent ratio of SGD, pose a great challenge to public health.

Bio-inspired Fabrication of Cu-Ni Coatings onto Mercerized Flax Fabric by Electroless Plating

Lin Zhu,Hang Zhao,Bijian Lan,Lei Hou,Siyi Bi,Yumeng Xu,Yinxiang Lu 한국섬유공학회 2020 Fibers and polymers Vol.21 No.2

This research mainly prepared a bio-friendly electromagnetic interference (EMI) shielding fabric, and discussed the influence of the grammage (i.e. 120 g/m2, 160 g/m2 and 210 g/m2, etc) of fabric substrate on the preparation of metalbased EMI shielding conductive fabric by electroless plating. A series of steps involved mercerization, dopamine (DoPA) modification, Ni0 seeding and electroless copper-nickel (Cu-Ni) plating were carried out to fabricate ideal EMI shielding fabric. The prepared Cu-Ni fabric endowed relatively high EMI shielding effectiveness (SE) (34.80-42.00 dB) ranging from 30 to 4500 MHz, which made it a huge potential in the field of wearable EMI shielding. Moreover, another discovery was that a relative higher grammage may lead to a lower total metal loading. Furthermore, Fourier transformation infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) measurements were conducted to verify the introduction of functional groups in mercerization, modification and activation procedures. The crystalline phases and morphologies of resulting Cu-Ni coatings were characterized by X-ray diffraction (XRD) and field emission-scanning electron microscopy (FE-SEM) measurements. The atomic ratio (at.%) of Cu and Ni in the sample was determined by Energy Dispersive X-ray Spectroscopy (EDX) measurements. Overall, the Cu-Ni alloy fabric prepared in this research met the requirements of health, coating lining and EMI shielding.

Latest research progress on anticancer effect of baicalin and its aglycone baicalein

Lin Wang,Ting Feng,Zhilian Su,Chao Pi,Yumeng Wei,Ling Zhao 대한약학회 2022 Archives of Pharmacal Research Vol.45 No.8

Cancer, which is a leading cause of deathsaround the world, is characterized by genetic mutationsand epigenetic changes. Baicalin and its aglycone baicalein,the major bioactive fl avones derived from the driedroot of Scutellaria baicalensis Georigi, belong to fl avonoidcompounds. Many studies demonstrated that both of themexhibited remarkable promising anticancer activities. Thisstudy summarized potential anticancer mechanisms of baicalinand baicalein including induction of apoptosis, initiationof cell cycle arrest, suppression of metastasis, induction ofautophagy, and regulation of immunity. Combination strategiesinvolving baicalin or baicalein as chemotherapeuticadjuvants, clinical trial and safety were also discussed. In addition, we compared the diff erence in their anticancereff ects. Interestingly, baicalein showed quicker and strongerinhibitory eff ects on multiple cancers than those of baicalin,probably due to its smaller size and high lipophilicity whichcontribute to fast absorption and improve ability to penetratecells. Taken together, both baicalin and baicalein are eff ectivein treating cancer with good tolerance. However, deglycosylationof baicalin to baicalein was found to have strongeranticancer potential.

Complete genome and phylogenetic analysis of bovine papillomavirus type 15 in Southern Xinjiang dairy cow

Hu, Jianjun,Zhang, Wanqi,Chauhan, Surinder Singh,Shi, Changqing,Song, Yumeng,Zhao, Yubing,Wang, Zhehong,Cheng, Long,Zhang, Yingyu The Korean Society of Veterinary Science 2020 Journal of Veterinary Science Vol.21 No.2

Background: Bovine papilloma is a neoplastic disease caused by bovine papillomaviruses (BPVs), which were recently divided into 5 genera and at least 24 genotypes. Objectives: The complete genome sequence of BPV type 15 (BPV Aks-02), a novel putative BPV type from skin samples from infected cows in Southern Xinjiang China, was determined by collecting warty lesions, followed by DNA extraction and amplicon sequencing. Methods: DNA was analyzed initially by polymerase chain reaction (PCR) using the degenerate primers FAP59 and FAP64. The complete genome sequences of the BPV Aks-02 were amplified by PCR using the amplification primers and sequencing primers. Sequence analysis and phylogenetic analysis were performed using bio-informatic software. Results: The nucleotide sequence of the L1 open reading frame (ORF) of BPV Aks-02 was 75% identity to the L1 ORF of BPV-9 reference strain from GenBank. The complete genome consisted of 7,189 base pairs (G + C content of 42.50%) that encoded 5 early (E8, E7, E1, E2, and E4) and 2 late (L1 and L2) genes. The E7 protein contained a consensus CX₂CX₂₉CX₂C zinc-binding domain and a LxCxE motif. Among the different members of this group, the percentages of the complete genome and ORFs (including 5 early and 2 late ORFs) sequence identity of BPV Aks-02 were closer to the genus Xipapillomavirus 1 of the Xipapillomavirus genus. Phylogenetic analysis and sequence similarities based on the L1 ORF of BPV Aks-02 revealed the same cluster. Conclusions: The results suggest that BPV type (BPV Aks-02) clustered with members of the Xipapillomavirus genus as BPV 15 and were closely related to Xipapillomavirus 1.

Complete genome and phylogenetic analysis of bovine papillomavirus type 15 in Southern Xinjiang dairy cow

Jianjun Hu,Wanqi Zhang,Surinder Singh Chauhan,Changqing Shi,Yumeng Song,Yubing Zhao,Zhehong Wang,Long Cheng,Yingyu Zhang 대한수의학회 2020 Journal of Veterinary Science Vol.21 No.6

Background: Bovine papilloma is a neoplastic disease caused by bovine papillomaviruses (BPVs), which were recently divided into 5 genera and at least 24 genotypes. Objectives: The complete genome sequence of BPV type 15 (BPV Aks-02), a novel putative BPV type from skin samples from infected cows in Southern Xinjiang China, was determined by collecting warty lesions, followed by DNA extraction and amplicon sequencing. Methods: DNA was analyzed initially by polymerase chain reaction (PCR) using the degenerate primers FAP59 and FAP64. The complete genome sequences of the BPV Aks-02 were amplified by PCR using the amplification primers and sequencing primers. Sequence analysis and phylogenetic analysis were performed using bio-informatic software. Results: The nucleotide sequence of the L1 open reading frame (ORF) of BPV Aks-02 was 75% identity to the L1 ORF of BPV-9 reference strain from GenBank. The complete genome consisted of 7,189 base pairs (G + C content of 42.50%) that encoded 5 early (E8, E7, E1, E2, and E4) and 2 late (L1 and L2) genes. The E7 protein contained a consensus CX2CX29CX2C zinc-binding domain and a LxCxE motif. Among the different members of this group, the percentages of the complete genome and ORFs (including 5 early and 2 late ORFs) sequence identity of BPV Aks-02 were closer to the genus Xipapillomavirus 1 of the Xipapillomavirus genus. Phylogenetic analysis and sequence similarities based on the L1 ORF of BPV Aks-02 revealed the same cluster. Conclusions: The results suggest that BPV type (BPV Aks-02) clustered with members of the Xipapillomavirus genus as BPV 15 and were closely related to Xipapillomavirus 1.