• Title/Summary/Keyword: PD-1/PD-L1

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Palladium(II) Schiff Base Complexes Derived from Allylamine and Vinylaniline

  • Uh, Yoon-Seo;Zhang, Hai-Wen;Vogels, Christopher M.;Decken, Andreae;Westcott, Stephen A.
    • Bulletin of the Korean Chemical Society
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    • v.25 no.7
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    • pp.986-990
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    • 2004
  • Condensation of salicylaldehyde $(2-HOC_6H_4C(O)H)$ with allylamine afforded the unsaturated salicylaldimine, $2-HOC_6H_4C(H)=NCH_2CH=CH_2$. Similar reactivity was observed with substituted salicylaldehydes. Further reaction of these Schiff bases with palladium acetate or $Na_2PdCl_4$ afforded complexes of the type $PdL_2$, where L = deprotonated Schiff base. The molecular structure of the parent salicylaldimine palladium complex $[trans-(2-OC_6H_4C(H)=NCH_2CH=CH_2)_2Pd]$ (1) was characterized by an X-ray diffraction study. Crystals of 1 were monoclinic, space group $P2_1/n,\;a\;=\;14.0005(9)\;{\AA},\;b\;=7.2964(5)\;{\AA},\;c\;=\;17.5103(12)\;{\AA},\;{\beta}\;=\;100.189(1)^{\circ}$, Z = 4. Analogous chemistry with 4-vinylaniline also gave novel palladium complexes containing a pendant styryl group. Crystals of $[trans-(2-HOC_6H_4C(H)=N-4-C_6H_4CH=CH_2)_2Pd]$ (4) were monoclinic, space group $P2_1/c$, a = 13.7710(14) ${\AA}$, b = 11.0348(11) ${\AA}$, c = 7.8192(8) ${\AA}$, ${\beta}\;=\;98.817(2)^{\circ}$, Z = 2.

Partial Oxidation of Methane to $H_2$ Over Pd/Ti-SPK and Pd/Zr-SPK Catalysts and Characterization (Pd/Ti-SPK과 Pd/Zr-SPK 촉매상에서 수소 생산을 위한 메탄의 부분산화반응과 촉매의 특성화)

  • Seo, Ho-Joon;Kang, Ung-Il
    • Applied Chemistry for Engineering
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    • v.21 no.6
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    • pp.648-652
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    • 2010
  • Catalytic activities of the partial oxidation of methane (POM) to hydrogen were investigated over Pd(5)/Ti-SPK and Pd(5)/Zr-SPK in a fixed bed flow reactor (FBFR) under atmosphere, and the catalysts were characterized by BET, XPS, XRD. The BET surface areas, pore volume and pore width of Horvath-Kawaze, micro pore area and volume of t-plot of Pd(5)/Ti-SPK and Pd(5)/Zr-SPK were $284m^2/g$, $0.233cm^3/g$, 3.9 nm, $30m^2/g$, $0.015cm^3/g$ and $396m^2/g$, $0.324cm^3/g$, 3.7nm, $119m^2/g$, $0.055cm^3/g$, repectively. The nitrogen adsorption isotherms were type IV with hysteresis. XPS showed that Si 2p and O 1s core electronlevels of Ti-SPK and Zr-SPK substituted Ti and Zr shifted to slightly lower binding energies than SPK. The oxidation states of Pd on the surface of catalysts were $Pd^0$ and $Pd^{+2}$. XRD patterns showed that crystal structures of fresh catalyst changed amorphous into crystal phase after reaction. The conversion and selectivity of POM to hydrogen over Pd(5)/Ti-SPK and Pd(5)/Zr-SPK were 77, 84% and 78, 72%, respectively, at 973 K, $CH_4/O_2$ = 2, GHSV = $8.4{\times}10^4mL/g_{cat}{\cdot}h$ and were kept constant even after 3 days in stream. These results confirm superior activity, thermal stability, and physicochemical properties of catalyst in POM to hydrogen.

Tristetraprolin Overexpression in Gastric Cancer Cells Suppresses PD-L1 Expression and Inhibits Tumor Progression by Enhancing Antitumor Immunity

  • Guo, Jian;Qu, Huiheng;Shan, Ting;Chen, Yigang;Chen, Ye;Xia, Jiazeng
    • Molecules and Cells
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    • v.41 no.7
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    • pp.653-664
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    • 2018
  • The RNA-binding protein tristetraprolin (TTP) binds to adenosine-uridine AU-rich elements in the 3'-untranslated region of messenger RNAs and facilitates rapid degradation of the target mRNAs. Therefore, it regulates the expression of multiple cancer and immunity-associated transcripts. Furthermore, a lack of TTP in cancer cells influences cancer progression and predicts poor survival. Although the functions of TTP on cancer cells have previously been researched, the mechanism of TTP on the interaction between cancer cells with their micro-environment remains undiscovered. In this study, we admed to determine the role of cancer cell TTP during the interaction between tumor and immune cells, specifically regulatory T cells (Tregs). We evaluate the capability of TTP to modulate the antitumor immunity of GC and explored the underlying mechanism. The overexpression of TTP in GC cells dramatically increased peripheral blood mononuclear lymphocyte (PBML) -mediated cytotoxicity against GC cells. Increased cytotoxicity against TTP-overexpressed GC cells by PBMLs was determined by Treg development and infiltration. Surprisingly, we found the stabilization of programmed death-ligand 1 (PD-L1) mRNA was declining while TTP was elevated. The PD-L1 protein level was reduced in TTP-abundant GC cells. PD-L1 gas been found to play a pivotal role in Treg development and functional maintenance in immune system. Taken together, our results suggest the overexpression of TTP in GC cells not only affects cell survival and apoptosis but also increases PBMLs -mediated cytotoxicity against GC cells to decelerate tumor progression. Moreover, we identified PD-L1 as a critical TTP-regulated factor that contributes to inhibiting antitumor immunity.

Influence of Oxygen to Population Pharmacokinetics/Pharmacodynamics of Alcohol in Healthy Volunteers (건강한 성인에서의 알코올의 집단 약물동태/약물동력에 미치는 산소의 영향 연구)

  • Song, Byungjeong;Back, Hyun-moon;Hwang, Si-young;Chae, Jung-woo;Yun, Hwi-yeol;Kwon, Kwang-il
    • Korean Journal of Clinical Pharmacy
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    • v.27 no.4
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    • pp.258-266
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    • 2017
  • Objective: To develop a population pharmacokinetics (PK)/pharmacodynamics (PD) model for alcohol in healthy volunteers and to elucidate individual characteristics to affects alcohol's PK or PD including dissolved oxygen. Methods: Following multiple intakes of total 540 mL alcohol (19.42 v/v%) to healthy volunteer, blood alcohol concentration was measured using a Breathe alcohol analyser (Lion SD-400 $Alcolmeter^{(R)}$). A sequential population PK/PD modeling was performed using NONMEM (ver 7.3). Results: Eighteen healthy volunteer were included in the study. PK model of alcohol was well explained by one-compartment model with first-order absorption and Michaelis-Menten elimination kinetics. $K_a$, V/F, $V_{max}$, $K_m$ is $8.1hr^{-1}$, 73.7 L, 9.65 g/hr, 0.041 g/L, respectively. Covariate analysis revealed that gender significantly influenced $V_{max}$ (Male vs Female, 9.65 g/hr vs 7.38 g/hr). PD model of temporary systolic blood pressure decreasing effect of alcohol was explained by biophase model with inhibitory $E_{max}$ model. $K_{e0}$, $I_{max}$, $E_0$, $IC_{50}$ were $0.23hr^{-1}$, 44.9 mmHg, 138 mmHg, 0.693 g/L, respectively. Conclusion: Model evaluation results suggested that this PK/PD model was robust and has good precision.

EFFECT OF GOLD ELECTRODEPOSIT OF PD-AG, NI-CR ALLOYS ON THE COLOR OF VENERRED RESIN (Pd-Ag 및 Ni-Cr 합금의 금 전착이 전장 레진의 색채에 미치는 영향)

  • Yang, Hong-So;Park, Yeong-Joon
    • The Journal of Korean Academy of Prosthodontics
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    • v.33 no.4
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    • pp.645-661
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    • 1995
  • As the mechanical property of composite resin improved, composite resin has been widely used esthetic dentistry. In the field of esthetic dentistry, the color of prosthetic material is very important. The purpose of this study was to evaluate the color difference of specimens, by the types of alloys and gold electrodeposit. Experimental groups were as follows : Group Prec : Au-Pt alloy with no gold coating and no resin veneer. Group Semi : Pd-Ag alloy with no gold coating and no resin veneer. Group BAse : Ni-Cr alloy with no gold coating and no resin veneer. Group Gsem : Pd-Ag alloy with no gold coating and no resin veneer. Group Gbas : Ni-Cr alloy with no gold coating and no resin veneer. Group PreR : Resin veneer on the Pd-Ag alloy without gold coating. Group SemR : Resin veneer on the Pd-Ag alloy without gold coating. Group GbsR : Resin veneer on the Ni-Cr alloy with gold coating Group BasR : Resin veneer on the Ni-Cr alloy without gold coating. In this study, colors of metal surfaces and veneered resins were evaluated by the CIE $L^{*}a^{*}b$ system. The results obtained were as follows : 1. different alloy types and gold coating make the $L^{*}a^{*}b$ system. 2. The ${\Delta}E^*$ab value between groups semi and Base was less than 1.5 and there was no $a^*$ and $b^*$ value difference between groups Gsem and Gbas 3. The values of $L^*$ and $a^*$ ain groups GsemR and GbasR were so similar that the ${\Delta}E^*$ab value was as small as 0.58. 4. In resin specimens with gold coated semiprecious or base alloys showed yellower and redder deviation than the resin specimens with precious alloy. 5. The ${\Delta}E^*$ab values between goups PreR-GsemR and groups PreR-GbasR were as small as 2.68 and 2.22 respectively.

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Overexpressions of xylA and xylB in Klebsiella pneumoniae Lead to Enhanced 1,3-Propanediol Production by Cofermentation of Glycerol and Xylose

  • Lu, Xinyao;Fu, Xiaomeng;Zong, Hong;Zhuge, Bin
    • Journal of Microbiology and Biotechnology
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    • v.26 no.7
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    • pp.1252-1258
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    • 2016
  • 1,3-Propanediol (1,3-PD) is a valuable platform compound. Many studies have shown that the supplement of NADH plays a key role in the bioproduction of 1,3-PD from Klebsiella pneumoniae. In this study, the xylA and xylB genes from Escherichia coli were overexpressed individually or simultaneously in K. pneumoniae to improve the production of 1,3-PD by cofermentation of glycerol and xylose. Compared with the parent strain, the xylose consumption was significantly increased by the introduction of these two genes. The 1,3-PD titers were raised from 17.9 g/l to 23.5, 23.9, and 24.4 g/l, respectively, by the overexpression of xylA and xylB as well as their coexpression. The glycerol conversion rate (mol/mol) was enhanced from 54.1% to 73.8%. The concentration of 2,3-butanediol was increased by 50% at the middle stage but drastically decreased after that. The NADH and NADH/NAD+ ratio were improved. This report suggests that overexpression of xylA or xylB is an effective strategy to improve the xylose assimilation rate to provide abundant reducing power for the biosynthesis of 1,3-PD in K. pneumoniae.

The role of matrix modifier for the determination of Lead (Pb) in blood by graphite furnace atomic absorption spectrometry (흑연로 원자흡수분광법에 의한 혈중 납분석시 매트릭스 변형제의 역할)

  • Yoo, Kwang-Sik;Kwon, Jin-Kee
    • Analytical Science and Technology
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    • v.5 no.4
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    • pp.349-358
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    • 1992
  • The direct determination of lead in the whole-blood by graphite furnace atomic absorption spectrometric analysis was carried out by using the sample which was diluted five-fold with 1% Triton X-100. Matrix modification was tried to remove the interferences of blood matrix and also to get the optimum analytical condition. Good agreement with certificated values in reference materials(bovine blood) supplied by comparison program in Japan was obstained when 1% $(NH_4)_2HPO_4$ as matrix modifier and ashing temperature, $700^{\circ}C$ were used or 1% $(NH_4)_2HPO_4$ and 0.1% $PdCl_2$ as matrix modifier and ashed at $700^{\circ}C$. Standard deviations were appeared as 2.2~6.3% for 1% $(NH_4)_2HPO_4$ and 3.1~9.1% for 1% $(NH_4)_2HPO_4$ and 0.1% $PdCl_2$ in the range of $31{\sim}624{\mu}gPb/l$.

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Optimization of the Reduced-Calorie Yellow Layer Cake Preparations (저열량 레이어 케익 제조 공정의 최적화)

  • Kim, Yang-Hwa;L.Kim, Hye-Young
    • Journal of the Korean Society of Food Culture
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    • v.18 no.1
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    • pp.37-44
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    • 2003
  • Fat and sugar reduced yellow layer cake system was developed with varied replacement level of 30%, 60%, and 90% for AD(amylodextrin) and 10%, 30%, and 50% for PD(polydextrose). Physicochemical and sensory characteristics were investigated and optimum replacement level was also decided using response surface methodology. Sample groups of PD10AD30 had significantly the lowest specific gravity and viscosity, indicating the stable batter system with high air incorporation. Sample groups with PD10AD90 showed the highest volume index and were not significantly different from those of the PD10AD30. Sensory results indicated that PD30AD30 were significantly the most springy and moist, and the least hard of all sample groups. Sample groups with PD10AD90 had the least adhesiveness value. To establish the optimum substitution level using RSM, the restriction level was set up as moistness over five point, hardness under five points, and adhesiveness under four points. The optimum substitution level was 20% for PD and 88% for AD.

A Manganese Coordination Polymer and a Palladium Molecular Compound of 3-Pyridinepropionic acid (HL): [MnL2(H2O)2] and trans-[Pd(HL)2Cl2]

  • Im, Seo Young;Lee, Soon W.
    • Bulletin of the Korean Chemical Society
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    • v.34 no.10
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    • pp.2947-2952
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    • 2013
  • Three coordination polymers, [$ML_2(H_2O)_2$] (M = Co (1), Ni (2), Mn (3)), were prepared from metal acetates ($M(CH_3COO)_2{\cdot}4H_2O$) and 3-pyridinepropionic acid ($HL=(3-py)-CH_2CH_2COOH$) by solvent-layer methods. By contrast, a discrete molecular compound, trans-[$Pd(HL)_2Cl_2$] (4), was synthesized by replacing benzonitrile (PhCN) ligands in trans-[$Pd(PhCN)_2Cl_2$] with HL under microwave-heating conditions. Compounds 1-3 have a 2D framework, and compound 4 contains a square-planar Pd metal.

Syntheses and Spectroscopic properties of Palladium(II) Complexes with Bidentate Aminophosphine of N,N-Dialkyl-N'-diphenylphosphinodiaminoethane

  • Doh, Myung-Ki;Kim, Bong-Gon
    • Bulletin of the Korean Chemical Society
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    • v.9 no.4
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    • pp.198-202
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    • 1988
  • Several new palladium(II) complexes of aminophosphines, $(Pd(L)X_2)$, (L = $Ph_2PNH$ ++ $NR_2$; R = $CH_3(L_1)$, $C_2H_5(L_2)$ : X = Cl, Br, I, and NCS) that contain two different donor atoms of nitrogen and phosphorus as ${\pi}$-electron acceptor, were synthesized and characterized by conductivity measurement, ir, and UV/Vis-spectra. For the dithiocyanatopalladium(II) complexes with aminophosphines, it was confirmed that the thiocyanate group trans to phosphorus is coordinated as Pd-NCS mode and the one trans to nitrogen as Pd-SCN mode, and the aminophosphines form six-membered chelate ring. The spectra of dihalogenopalladium(II) complexes with aminophosphines show that the band maxima are shifted to the short wavelengths as the concentration is decreased.