• Title/Summary/Keyword: Pd

Search Result 4,885, Processing Time 0.034 seconds

Molecular Orbital Interpretation on Antitumor Activity of trans-Palladium(Ⅱ) Complexes by Geometrical Structure of Ligands (Ⅰ) (리간드의 기하학적 구조에 의한 trans-팔라듐(Ⅱ) 착물의 항암활성에 관한 분자궤도함수론적 해석 (Ⅰ))

  • Song, Young Dae;Park, Byung Kak
    • Journal of the Korean Chemical Society
    • /
    • v.39 no.4
    • /
    • pp.244-251
    • /
    • 1995
  • The palladium(II) complexes(where, [Pd(L)2X2], L=isoxazole(isox), 3,5-dimethylisoxazole(3,5-diMeisox), 3-methyl, 5-phenylisoxazole(3-Me, 5-Phisox), and 4-amino, 3,5-dimethylisoxazole(4-ADI); X=Cl, Br] with isoxazole and its derivatives are investigated on antitumor activity by EHMO calculation. It is found that the net charge of the two halogen atoms in trans-isomers are greater than those in cis-ones, indicating that ionic character of Pd-X bond in trans-isomers is greater than that of cis-ones, and so dissociation of Cl- ion is easier than that of Br- ion in aqueous solution in body. Furthermore, it is found that the ${\sigma}MO$ energy of Pd(dx2-y2)-X(px) bond $(E{\sigma}(Pd-X))$ is higher than that of Pd(dx2-y2)-N(px) bond $(E{\sigma}(Pd-N))$ without exception, about all the complexes, and also the $E{\sigma}(Pd-X)$ of trans-isomers is higher than that of cis-isomers. From the above facts, the degree of dissociation in Pd-X bond would be related to antitumor activity. In fact, the linear equation of correlation coefficient 0.96 is fairly established between ${\Delta}E{\sigma}(N-X)(E\sigma(Pd-N)-E{\sigma}(Pd-X))$ and inhibitory activity coefficient, logIA.

  • PDF

Bayberry Tannin as Stabilizer for the Synthesis of Highly Active and Reusable Heterogeneous Pd Catalysts and Their Application in the Catalytic Hydrogenation of Olefins

  • Chen, Chen;Lv, Guang;Huang, Xin;Liao, Xue Pin;Zhang, Wen Hua;Shi, Bi
    • Bulletin of the Korean Chemical Society
    • /
    • v.33 no.2
    • /
    • pp.403-408
    • /
    • 2012
  • In this study, the homogenous Pd nanoparticles (Pd NPs) were first prepared with bayberry tannin (BT) as the stabilizers. Subsequently, the obtained bayberry tannin-stabilized Pd nanoparticles (BT-Pd) were immobilized onto ${\gamma}-Al_2O_3$ to prepare heterogeneous ${\gamma}-Al_2O_3$-BT-Pd catalysts. Fourier Transformation Infrared Spectrum (FTIR) and X-ray Photoelectron Spectroscopy (XPS) analyses confirmed that the Pd NPs were well stabilized by the phenolic hydroxyl groups of BT. Transmission Electron Microscopy (TEM) observation indicated that the diameter of the Pd NPs can be effectively controlled in the range of 4.2-16.0 nm by varying the amount of BT. It is found that the ${\gamma}-Al_2O_3$-BT-Pd catalysts exhibit highly activity for various olefin hydrogenations. For example, the initial TOF (turnover frequency) of the ${\gamma}-Al_2O_3$-BT-Pd in the allyl alcohol hydrogenation is as high as $12804 mol{\cdot}mol^{-1}{\cdot}h^{-1}$. Furthermore, the ${\gamma}-Al_2O_3$-BT-Pd can be reused 5 times without significant loss of activity, exhibiting a superior reusability as compared with conventionally prepared ${\gamma}-Al_2O_3$-Pd catalysts.

Correlation of PD-L1 Expression Tested by 22C3 and SP263 in Non-Small Cell Lung Cancer and Its Prognostic Effect on EGFR Mutation-Positive Lung Adenocarcinoma

  • Kim, Taehee;Cha, Yoon Jin;Chang, Yoon Soo
    • Tuberculosis and Respiratory Diseases
    • /
    • v.83 no.1
    • /
    • pp.51-60
    • /
    • 2020
  • Background: Programmed death-ligand 1 (PD-L1) expression is tested by immunohistochemistry (IHC)-22C3, SP263, and SP142. The aim of this study is to evaluate the correlation among the three methods of PD-L1 IHC in non-small cell lung cancer (NSCLC) and clinical significance of PD-L1 expression in lung adenocarcinoma with an epidermal growth factor receptor (EGFR)-tyrosine kinase domain mutation. Methods: The results of 230 patients who were pathologically confirmed as having NSCLC; tested using PD-L1 IHC 22C3, SP263, and SP142 methods; and evaluated via the peptide nucleic acid clamping method to confirm EGFR mutation, were analyzed in this study. Results: 164 patients underwent both the SP263 and 22C3 tests. There was a significant positive correlation between the outcomes of the two tests (Spearman correlation coefficient=0.912, p<0.001), with a derived regression equation as follows: 22C3=15.2+0.884×SP263 (R2=0.792, p<0.001). There was no relationship between the expression of PD-L1 and clinical parameters, including EGFR-tyrosine kinase inhibitor (TKI) mutation. The PD-L1 expression in patients treated with EGFR-TKI yielded a 2-month-shorter progression period than that in the PD-L1-negative group. However, this did not reach statistical significance (PD-L1<1% vs. PD-L1≥1%, 10 months vs. 8 months). Conclusion: The results of the 22C3 and those of SP263 methods were in good correlation with one another. Since the PD-L1 expression is not influenced by the EGFR mutation, it is necessary to perform a PD-L1 test to set the treatment direction in the patients with EGFR-mutant NSCLC.

First-Principles Theoretical Study of the Surface Structure of O/Pd(100)-p($2{\times}2$) and the Effect of H Impurities (O/Pd(100)-p($2{\times}2$) 표면구조 및 수소흡착 효과의 제일원리 이론계산 연구)

  • Jung Sung-Chul;Kang Myung-Ho
    • Journal of the Korean Vacuum Society
    • /
    • v.15 no.4
    • /
    • pp.360-366
    • /
    • 2006
  • We have performed density functional theory calculations for the surface structure of O/Pd(100)-p($2{\times}2$), formed by the adsorption of oxygen atoms of 0.25 ML. The oxygen atoms adsorb preferentially at the fourfold hollow site, and the calculated O-Pd bond length is $2,15{\AA}$, The first interlayer spacing ($d_{12}$) of Pd(100) expands by +0.8% due to the oxygen adsorption, which differs from the experimental value of +3.6% reported by a previous LEED study. Assuming that the LEED sample was possibly contaminated by hydrogen atoms, we also examined the effect of hydrogen impurities on the surface structure. Hydrogen atoms adsorbed on O/Pd(100)-p($2{\times}2$) are found to result in large expansions of $d_{12}$ of Pd(100). Our analysis estimates the amount of hydrogen atoms remaining on the LEED sample as -0.3 ML.

Reliability of Sn-Ag-Cu Solder Joint on ENEPIG Surface Finish: 2. Effects of time of Pd activation (ENEPIG 표면처리에서의 Sn-Ag-Cu 솔더조인트 신뢰성: 2. Pd 촉매 시간의 영향)

  • Huh, Seok-Hwan;Lee, Ji-Hye;Ham, Suk-Jin
    • Journal of the Microelectronics and Packaging Society
    • /
    • v.21 no.3
    • /
    • pp.51-56
    • /
    • 2014
  • The reliability of solder joint is significantly affected by the property of surface finish. This paper reports on a study of high speed shear energy and failure mode for Sn-4.0wt%Ag-0.5wt%Cu (SAC405) solder joints with the time of Pd activation. The nodule size of electroless Ni-P deposit increased with increasing the time of Pd activation. The roughness (Ra) of electroless Ni-P deposit decreased with increasing the time of Pd activation. Then, with $HNO_3$ vapor, the quasi-brittle and brittle mode of SAC405 solder joint decreased with increasing the time of Pd activation. This results indicate that the increase in the Pd activation time for Electroless Ni/ Electroless Pd/ Immersion Au (ENEPIG) surface finish play a critical role for improving the robustness of SAC405 solder joint.

Changes of Glucose-6-Phosphate Dehydrogenase on Alloxan-induced Diabetic Rat (Alloxan으로 유발된 당뇨쥐의 간조직 Glucose-6-Phosphate Dehydrogenase 효소의 변화)

  • 박수영;조경혜
    • Biomedical Science Letters
    • /
    • v.3 no.2
    • /
    • pp.169-175
    • /
    • 1997
  • The hypoglycemic and metabolic effects of Commelina communis L. extract were investigated in alloxan-induced diabetic rats. The increased blood glucose level in the diabetic rats was sinificantly lowered with the treatments of the plant protein extract. Administration of the plant extract ellicited the significant increase of glucose-6-phosphate dehydrogenase (G6PD) activity in liver of alloxan-induced rats. Three isozyme patterns(band I, II & III : in order decreasing mobility) of G6PD were found when normal rat liver extract were subjected to electrophoresis on native polyacrylamide gel. On the other hand, G6PD band patterns of alloxan-induced rat liver extract were found band II isozyme missing. By treatment of plant extract in alloxan-induced rats has been showed pattern the recovery of missing band patterns. This indicates that changes of the G6PD isozyme might be related to the cellular process of diabetes.

  • PDF

Clinical Characteristics of Female Panic Disorder with Early Sexual Abuse History (초기 성 학대 경험이 있는 여성 공황장애 환자의 임상적 특성)

  • Kim, Kyung Min;Kim, Min-Kyoung;Lee, Kang Soo;Choi, Tai Kiu;Lee, Sang-Hyuk
    • Korean Journal of Biological Psychiatry
    • /
    • v.23 no.4
    • /
    • pp.130-139
    • /
    • 2016
  • Objectives The objective of this study is to investigate differences of clinical characteristics between a healthy female control group and female panic disorder (PD) patients with early sexual abuse history (PD+S) and without early sexual abuse history (PD-S). Methods We examined data from 83 patients diagnosed with PD and 20 healthy control subjects. We divided the patients with PD into PD+S (32 patients) and PD-S (51 patients) to compare demographic and clinical characteristics. The following instruments were applied: the Stress coping strategies, the Beck Depression Inventory (BDI), the Panic Disorder Severity Scale, the Anxiety Sensitivity Index-Revised (ASI-R), the Albany Panic and Phobia Questionnaire (APPQ) and the NEO-neuroticism. Results Compared to the PD-S, the PD+S group showed higher scores in neuroticism and the APPQ. And, in the PD+S group, the scores of neuroticism were correlated with the ASI-R and APPQ subscale scores and the APPQ total scores were associated with the scores of BDI. Conclusions This study shows that female PD+S patients have higher scores in neuroticism and the APPQ than the PD-S group, and these factors are associated with the panic-related symptoms severity. It emphasizes the need of specific strategies considering the childhood abuse history such as early sexual abuse in clinical approach among patients with PD.

Systemic and Cell-Type Specific Profiling of Molecular Changes in Parkinson's Disease

  • Lee, Yunjong
    • Interdisciplinary Bio Central
    • /
    • v.4 no.3
    • /
    • pp.6.1-6.12
    • /
    • 2012
  • Parkinson's disease (PD) is a complicated neurodegenerative disorder although it is oftentimes defined by clinical motor symptoms originated from age dependent and progressive loss of dopaminergic neurons in the midbrain. The pathogenesis of PD involves dopaminergic and nondopaminergic neurons in many brain regions and the molecular mechanisms underlying the death of different cell types still remain to be elucidated. There are indications that PD causing disease processes occur in a global scale ranging from DNA to RNA, and proteins. Several PD-associated genes have been reported to play diverse roles in controlling cellular functions in different levels, such as chromatin structure, transcription, processing of mRNA, translational modulation, and posttranslational modification of proteins. The advent of quantitative high throughput screening (HTS) tools makes it possible to monitor systemic changes in DNA, RNA and proteins in PD models. Combined with dopamine neuron isolation or derivation of dopamine neurons from PD patient specific induced pluripotent stem cells (PD iPSCs), HTS techonologies will provide opportunities to draw PD causing sequences of molecular events in pathologically relevant PD samples. Here I discuss previous studies that identified molecular functions in which PD genes are involved, especially those signaling pathways that can be efficiently studied using HTS methodologies. Brief descriptions of quantitative and systemic tools looking at DNA, RNA and proteins will be followed. Finally, I will emphasize the use and potential benefits of PD iPSCs-derived dopaminergic neurons to screen signaling pathways that are initiated by PD linked gene mutations and thus causative for dopaminergic neurodegneration in PD.

Clinical Characteristics of Female Panic Disorder Patients with Abortion History (유산 경험이 있는 여성 공황장애 환자의 임상적 특성)

  • Hwang, Hye Jin;Oh, Jongsoo;Bang, Minji;Won, Eunsoo;Lee, Kang Soo;Choi, Tai Kiu;Lee, Sang-Hyuk
    • Korean Journal of Biological Psychiatry
    • /
    • v.26 no.2
    • /
    • pp.65-70
    • /
    • 2019
  • Objectives The objective of this study is to investigate differences in clinical characteristics between female panic disorder (PD) patients with abortion history (PD+A) and without abortion history (PD-A). Methods We examined data from 341 female patients diagnosed with PD. We divided the patients with PD into PD+A (82 patients) and PD-A (259 patients) to compare demographic and clinical characteristics. The following instruments were applied : stress coping strategies, NEO-neuroticism, the Anxiety Sensitivity Index-Revised (ASI-R), the Albany Panic and Phobia Questionnaire (APPQ), the Beck Depression Inventory, the Beck Anxiety Inventory (BAI) and the Sheehan Disability Scale. Results Compared to the PD-A, the PD+A group showed no significant difference in coping strategies. However, significantly higher scores in neuroticism, the ASI-R, the APPQ and the BAI were observed. In terms of health-related disability, the PD+A group did not show significant difference. Conclusions Our results suggest that the PD+A group may differ from the PD-A group in trait markers such as neuroticism and anxiety sensitivity, and abortion history may be associated with panic-related symptom severity. Our study suggests that further consideration is needed on such clinical characteristics in PD patients with abortion history.

Electrochemical Corrosion Characteristics of Dental Prostheses High-Palladium Alloys (치과용 고-Pd계 합금의 부식특성)

  • 김기주;이진형
    • Journal of Biomedical Engineering Research
    • /
    • v.22 no.6
    • /
    • pp.511-518
    • /
    • 2001
  • In vitro corrosion resistance of the commercially used 76.5wt.%Pd-17.6%Cu-7.2%Ga and 77.3%Pd-6.0%Ga dental Prostheses high-Palladium system alloys in cast, degassing and porcelain-firing heat treatment conditions were evaluated by the potentiodynamic polarization technique in the de-aerated 0.9%NaCl and a modified Fusayama electrolyte. From the corrosion rate experimental results, we found that there is a small difference in the corrosion resistance depending on the microstructure. However. it was so small that there is no significant problem as a dental material. The 77.3%Pd-6.0%Ga showed better corrosion resistance than the 76.5%Pd-11.6%Cu-7.2%Ga dental Prostheses high-palladium system alloys. These experimental observations in 76.5%Pd-11.6%Cu-7.2%Ga alleys are mainly due to a rapid quenching and Cu in the alloy which accelerate the eutectic reaction with a segregation and Precipitates in the microstructure. On the ocher hand, 77.3%Pd-6.0%Ga alloys, which are solid-solution matrix, show much better col·lesion resistance compared with that of 76.5%Pd-11.6%Cu-7.2%Ga alloys.

  • PDF