Stepwise selective reaction of two N-cyanoethyl groups attached to C-racemic tetraaza macrocyclic nickel(II) and copper(II) complexes in aqueous solutions

Kang, S.G.,Kim, N.,Jeong, J.H. Elsevier Sequoia [etc.] 2011 Inorganica chimica acta Vol.366 No.1

Stepwise hydrolysis of two N-(CH<SUB>2</SUB>)<SUB>2</SUB>CN groups attached to [Ni(C-racemic-L<SUP>2</SUP>)(OAc)]<SUP>+</SUP> and [Cu(C-racemic-L<SUP>2</SUP>)]<SUP>2+</SUP> (L<SUP>2</SUP>=1,8-bis(N-cyanoethyl)-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) has been investigated. The reaction of [Ni(C-meso-L<SUP>2</SUP>)]<SUP>2+</SUP> has also been examined. Interestingly, [Ni(C-racemic-L<SUP>2</SUP>)(OAc)]<SUP>+</SUP> is readily hydrolyzed to [Ni(C-racemic-L<SUP>3</SUP>)]<SUP>2+</SUP> bearing one N-(CH<SUB>2</SUB>)<SUB>2</SUB>CONH<SUB>2</SUB> and one N-(CH<SUB>2</SUB>)<SUB>2</SUB>CN pendant arms at pH @?6, whereas [Cu(C-racemic-L<SUP>2</SUP>)]<SUP>2+</SUP> and [Ni(C-meso-L<SUP>2</SUP>)]<SUP>2+</SUP> are quite inert against hydrolysis under similar acidic conditions. Although [Cu(C-racemic-L<SUP>2</SUP>)]<SUP>2+</SUP> is hydrolyzed to [Cu(C-racemic-L<SUP>3</SUP>)]<SUP>2+</SUP> at pH 9, [Ni(C-meso-L<SUP>2</SUP>)]<SUP>2+</SUP> readily undergoes C-N bond cleavage to yield [Ni(C-meso-L<SUP>1</SUP>)]<SUP>2+</SUP> (L<SUP>1</SUP>=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) in basic aqueous solutions. The hetero-functionalized complex [Ni(C-racemic-L<SUP>3</SUP>)]<SUP>2+</SUP> undergoes hydrolysis and C-N bond cleavage at pH 9 and 13, respectively; both [Ni(C-racemic-L<SUP>4</SUP>)]<SUP>2+</SUP> bearing two N-(CH<SUB>2</SUB>)<SUB>2</SUB>CONH<SUB>2</SUB> pendant arms and [Ni(C-racemic-L<SUP>5</SUP>)]<SUP>2+</SUP> bearing one N-(CH<SUB>2</SUB>)<SUB>2</SUB>CONH<SUB>2</SUB> group can be prepared selectively by controlling pH of the solution. However, [Cu(C-racemic-L<SUP>3</SUP>)]<SUP>2+</SUP> readily undergoes C-N bond cleavage to produce [Cu(C-racemic-L<SUP>5</SUP>)]<SUP>2+</SUP> even at pH 9. Crystal structure of [Ni(C-racemic-L<SUP>3</SUP>)]<SUP>2+</SUP> shows that the complex has severely distorted trigonal bipyramidal coordination geometry. Electronic absorption spectra of [Cu(C-racemic-L<SUP>3</SUP>)]<SUP>2+</SUP>, [Ni(C-racemic-L<SUP>5</SUP>)]<SUP>2+</SUP>, and [Cu(C-racemic-L<SUP>5</SUP>)]<SUP>2+</SUP> indicate that they also have trigonal bipyramidal coordination geometry.

Effect of controlled O₂ impurities on N₂ afterglows of RF discharges

Kang, N.,Lee, M.,Ricard, A.,Oh, S.g. Elsevier 2012 Current Applied Physics Vol.12 No.6

A RF capacitive flowing discharge and post-discharge are experimentally studied in N<SUB>2</SUB> gas and N<SUB>2</SUB>-(10<SUP>-4</SUP>-10<SUP>-2</SUP>)O<SUB>2</SUB> gas mixtures by using the optical emission spectroscopy at a pressure of 8 Torr, a flow rate of 1 slm and a transmitted RF power of 100 W. In these conditions the flowing discharge is distinguished by early and late afterglow. It is shown that the early afterglow is very sensitive to small quantity of O<SUB>2</SUB>. The band emissions from N<SUB>2</SUB><SUP>+</SUP>(B) and N<SUB>2</SUB>(B,υ') decreased sharply in the early afterglow when O<SUB>2</SUB> is introduced before the plasma. By using simple gas kinetics for pseudo-stationary conditions in the afterglows, N<SUB>2</SUB><SUP>+</SUP>+O<SUB>2</SUB> charge transfer and N<SUB>2</SUB>(a') quenching by O<SUB>2</SUB> play key roles in the afterglow. The charge transfers and quenching reactions are amplified when O-atoms are produced in the plasma. It is also observed that the O-atoms are produced in the early afterglow when O<SUB>2</SUB> is introduced after the plasma.

The prolyl isomerase Pin1 interacts with a ribosomal protein S6 kinase to enhance insulin-induced AP-1 activity and cellular transformation

Lee, N. Y.,Choi, H.-K.,Shim, J.-H.,Kang, K.-W.,Dong, Z.,Choi, H. S. Oxford University Press 2009 Carcinogenesis Vol.30 No.4

<P>Phosphorylation of proteins on serine or threonine residues that immediately precede proline (pSer/Thr-Pro) is specifically catalyzed by the peptidyl-prolyl cis-trans isomerase Pin1 and is a central signaling mechanism in cell proliferation and transformation. Although Pin1 is frequently overexpressed in hepatocellular carcinoma (HCC), the molecular mechanism of Pin1 in HCC has not been completely elucidated. Here, we show that Pin1 interacts with p70S6K in vitro and ex vivo. Overexpression of Pin1 resulted in enhanced p70S6K phosphorylation induced by insulin in SK-HEP-1 cells. In contrast, Pin1(-/-) mouse embryonic fibroblasts (MEFs) exhibited significantly decreased insulin-induced p70S6K phosphorylation compared with Pin1(+/+) MEFs. Furthermore, Pin1 enhanced the insulin-induced extracellular signal-regulated protein kinase (ERK)1/2 phosphorylation through its interaction with p70S6K, whereas the inhibition of p70S6K activity by rapamycin suppressed insulin-induced ERK1/2 phosphorylation in SK-HEP-1 cells. Hence, Pin1 affected activator protein-1 activity through p70S6K-ERK1/2 signaling in SK-HEP-1 cells. Most importantly, Pin1-overexpressing JB6 Cl41 cells enhanced neoplastic cell transformation promoted by insulin much more than green fluorescent protein-overexpressing JB6 Cl41 control cells. These results imply that Pin1 amplifies insulin signaling in hepatocarcinoma cells through its interaction with p70S6K, suggesting that Pin1 plays an important role in insulin-induced tumorigenesis and is a potential therapeutic target in hepatocarcinoma.</P>

Electrocatalytic activity of chemically deposited Cu_xS thin film for counter electrode in quantum dots-sensitized solar cells

Lim, I.,Lee, D.Y.,Patil, S.A.,Shrestha, N.K.,Kang, S.H.,Nah, Y.C.,Lee, W.,Han, S.H. Elsevier Science Publishers 2014 Materials chemistry and physics Vol.148 No.3

The compact (c-Cu<SUB>x</SUB>S) and the porous (p-Cu<SUB>x</SUB>S) with particle decorated films of coppers-ulfidearesynthesized using a chemical bath deposition technique, and the films are characterized using electrochemical techniques. In addition, the chemically deposited Cu<SUB>x</SUB>S films are investigated as a counter electrode in quantum dots-sensitized solar cells (QSSCs). The available redox active reaction sites of the p-Cu<SUB>x</SUB>S film are found to be 57.9% higher than those available in the c-Cu<SUB>x</SUB>S film. From the electrochemical impedance spectroscopy, the effective diffusion coefficients of the polysulfide electrolyte in the c-Cu<SUB>x</SUB>S and p-Cu<SUB>x</SUB>S films are estimated to be 3.67 x 10<SUP>-5</SUP> and 6.35 x 10<SUP>-5</SUP> cm<SUP>2</SUP> s<SUP>-1</SUP>, respectively. These results can be ascribed to the improvement in the available redox active reaction sites and the electrocatalytic activity of the Cu<SUB>x</SUB>S counter electrode. As compared to the c-Cu<SUB>x</SUB>S film, the p-Cu<SUB>x</SUB>S film as a counter electrode exhibits an enhanced photovoltaic performance of the QSSCs with the power conversion efficiency of 3.17%, short-circuit current of 11.89 mA c<SUP>-</SUP>m<SUP>2</SUP>, open-circuit voltage of 0.50 V, and fill factor of 53.29. The improved performance of the QSSCs is ascribed to the improvements on the available redox active reaction sites, electrocatalytic activity and the diffusion coefficients, which are directly related to the surface morphology of the sulfide films.

Non-covalent functionalization of graphene with poly(diallyl dimethylammonium) chloride: Effect of a non-ionic surfactant

Kaur, P.,Shin, M.S.,Sharma, N.,Kaur, N.,Joshi, A.,Chae, S.R.,Park, J.S.,Kang, M.S.,Sekhon, S.S. Pergamon Press ; Elsevier Science Ltd 2015 International journal of hydrogen energy Vol.40 No.3

Carbon based nanomaterials (carbon nanotubes, graphene etc) containing various hetero atoms are promising metal free catalysts for oxygen reduction reaction in fuel cells. We report the non-covalent functionalization of graphene with poly(diallyl dimethylammonium) chloride (PDDA), a polyelectrolyte containing nitrogen, using a very simple method. The addition of a non-ionic surfactant (Triton X-100) during functionalization has been observed to improve the interactions between graphene and PDDA. An up-shift in the position of G-peak in the Raman spectra, down-shift in the binding energy (B.E.) of N1s peak and an up-shift in the B.E. of C1s peak in XPS spectra have been observed due to an inter-molecular charge-transfer from carbon in graphene to nitrogen in PDDA, which get enhanced in the presence of Triton X-100. Graphene functionalized with PDDA also show good thermal stability. The addition of a non-ionic surfactant enhances the non-covalent functionalization of graphene with PDDA, which is desirable from applications point of view.

Amantadine-resistant influenza A viruses isolated in South Korea from 2003 to 2009

Choi, W.Y.,Kim, S.,Lee, N.,Kwon, M.,Yang, I.,Kim, M.J.,Cheong, S.G.,Kwon, D.,Lee, J.Y.,Oh, H.B.,Kang, C. Elsevier/North-Holland 2009 ANTIVIRAL RESEARCH Vol.84 No.2

To investigate the frequency of amantadine resistance among influenza A viruses isolated in Korea during the 2003-2009 seasons, 369 (16.8%) 2199 A/H1N1 viruses and 780 (14.8%) of 5263 A/H3N2 viruses were randomly selected. The M2 and HA1 genes of each isolate were amplified by reverse transcription-polymerase chain reaction and followed by nucleotide sequencing. The results showed that the resistance rate to amantadine among A/H1N1 viruses increased significantly from 2004-2005 (33.3%) to 2007-2008 (97.8%) and then decreased dramatically in 2008-2009 (1.9%). The A/H1N1 isolates recently detected in 2008-2009 turned amantadine-sensitive containing two new substitutions at specific sites (S141N, G185A) in HA1. Compared with A/H1N1 viruses, the amantadine resistance among the A/H3N2 viruses increased from 2003-2004 (9.7%) to 2005-2006 (96.7%) and decreased in 2006-2007 (57.4%). During 2006-2007, both of amantadine-resistant and -sensitive A/H3N2 viruses co-circulated but clustered in different branches phylogenetically. All of A/H3N2 isolates tested during 2007-2009 appeared to cluster in the same group being resistant to amantadine.

Allogeneic hematopoietic cell transplantation for myelodysplastic syndrome: prognostic significance of pre-transplant IPSS score and comorbidity

Lee, J-H,Lee, J-H,Lim, S-N,Kim, D-Y,Kim, S H,Lee, Y-S,Kang, Y-A,Kang, S-I,Jeon, M J,Seol, M,Seo, E-J,Chi, H S,Park, C J,Jang, S,Yun, S-C,Lee, K-H Macmillan Publishers Limited 2010 BONE MARROW TRANSPLANTATION -BASINGSTOKE- Vol.45 No.3

We analyzed the clinical significance of pre-transplant International Prognostic Scoring System (IPSS) score and comorbidity in 68 patients who underwent allogeneic hematopoietic cell transplantation (HCT) for myelodysplastic syndrome (MDS) (n=48) or acute myeloid leukemia evolved from MDS (n=20) between December 1995 and January 2008 in a single institute. During a median follow-up period of 41.0 months (range, 3.2–132.0 months), 27 patients died, and 7 relapsed. The 5-year probabilities of overall survival (OS) and event-free survival (EFS) were 60.0 and 57.4%, respectively, and the 5-year cumulative incidences of non-relapse mortality (CINRM) and relapse were 32.7 and 9.9%, respectively. OS, EFS, and CINRM were significantly different according to pre-transplant IPSS score and presence of pre-transplant comorbidity, which were independent risk factors along with Karnofsky performance score in multivariate analyses. In conclusion, pre-transplant IPSS score and comorbidity may stratify the risk of post transplant outcomes in MDS.

Reduced-Intensity Conditioning with Busulfan, Fludarabine, and Antithymocyte Globulin for Hematopoietic Cell Transplantation from Unrelated or Haploidentical Family Donors in Patients with Acute Myeloid Leukemia in Remission

Lee, K.H.,Lee, J.H.,Lee, J.H.,Kim, D.Y.,Park, H.S.,Choi, E.J.,Ko, S.H.,Seol, M.,Lee, Y.S.,Kang, Y.A.,Jeon, M.,Baek, S.,Kang, Y.L.,Kim, S.H.,Yun, S.C.,Kim, H.,Jo, J.C.,Choi, Y.,Joo, Y.D.,Lim, S.N. Kluge Carden Jennings Pub. Co 2017 BIOLOGY OF BLOOD AND MARROW TRANSPLANTATION Vol.23 No.9

To investigate the role of antithymocyte globulin (ATG)-containing reduced-intensity conditioning (RIC) in hematopoietic cell transplantation (HCT) from unrelated (UD) or haploidentical family donors (HFD), we conducted a phase 2 trial of 237 patients (age range, 16 to 69 years) with acute myeloid leukemia (AML) in remission. Patients undergoing UD-HCT (n@?=@?93) or HFD-HCT (n@?=@?59) received RIC comprising busulfan, fludarabine, and ATG, 9@?mg/kg, whereas those undergoing HCT from matched sibling donors (MSD, n@?=@?85) received myeloablative busulfan and cyclophosphamide conditioning or aforementioned RIC with ATG, 4.5@?mg/kg. For graft-versus-host disease (GVHD) prophylaxis, cyclosporine and methotrexate were administered. The median follow-up period was 44.7 months after HCT for 161 survivors. For UD-HCT versus HFD-HCT, there were no significant differences in leukemia recurrence, nonrelapse mortality, relapse-free survival, grades 2 to 4 acute GVHD, and moderate-to-severe chronic GVHD. Furthermore, when the outcomes of UD-HCT and HFD-HCT were combined and compared with those of MSD-HCT, there were no significant differences in leukemia recurrence (3-year cumulative incidence, 30% versus 29%), nonrelapse mortality (3-year cumulative incidence, 7% versus 8%), relapse-free survival (3-year estimate, 63% versus 63%), and grades 2 to 4 acute GVHD (120-day cumulative incidence, 16% versus 13%). Moderate-to-severe chronic GVHD, however, occurred less frequently in UD/HFD-HCT (2-year cumulative incidence, 22% versus 40%; P@?=@?.006). The addition of ATG to conditioning regimen was a significant predictor for less chronic GVHD (subdistribution hazard ratio, .59). In AML in remission, UD/HFD-HCT after ATG-containing RIC achieved leukemia control equivalent to that of MSD-HCT. Despite HLA disparity in UD/HFD-HCT, chronic GVHD occurred less frequently after ATG-containing RIC, suggesting a strong GVHD-modulating effect of ATG.

Fentanyl Transdermal System의 약물사용평가

심릿다,윤혜영,오지영,강진숙,김옥녀 한국병원약사회 1997 병원약사회지 Vol.14 No.1

DUROESIC^(R) is a transdermal patch providing continuous systemic delivery of fentanyl, a potent opioid analgesic for 72 hours. A retrospective Drug Use (DUE) study on fentanyl Transdermal Therapeutic System(TTS) was conducted. The charts of 50 patients, hospitalized at St. Mary's Hospital from March 1. 1996 to May 31. 1996 and applied fentanyl TTS, were reviewed. The procedure collaborated DUS criteria for fentanyl TTS established by American Journal of health-system pharmacists(AJHP) and manufacturer's guideline. The following information was gathered for patient; indication for use, initial dosage, and dosage interval. As a result, 46 patients(96%) met the criteria for indication of use, 30 patients met the criteria for initial dosage conforms, and 42 patients met criteria for dosage interval. Adverse effects, constipation(44%), nausea/vomiting(23%), respiratory depression (13%), etc, were observed. This study suggests the education for TTS dosage form needs to be provided to medical team.

Enhanced performance of organic electroluminescence diodes with a 2-TNATA:C60 hole injection layer

Kang, H.S.,Park, K.N.,Cho, Y.R.,Park, D.W.,Choe, Y. Korean Society of Industrial and Engineering Chemi 2009 Journal of industrial and engineering chemistry Vol.15 No.5

C60-doped 2-TNATA (4,4',4''-tris(2-naphthylphenylamino)triphenylamine) as a hole injection material and NPD (4,4'bis[N-(1-naphthyl)-N-phenyl-amino]biphenyl) as a hole transport material are used to fabricate OLEDs via vacuum deposition process in this study. C60-doped 2-TNATA film was treated by means of thermal annealing and in situ electromagnetic field. According to AFM, SEM, XRD, and Raman spectra results, by both thermal annealing and in situ electromagnetic field treatments, the smoothened surface and the closely packed morphology of 2-TNATA:C60 film was obtained without any evidences of crystalline nature after those treatments. The treatments eventually lead to enhancing the current density and efficiency of the multi-layered ITO/2-TNATA:C60 (5% doped) (70nm)/NPD (30nm)/Alq<SUB>3</SUB> (50nm)/LiF (1nm)/Al (100nm) devices by facilitating hole injection/transport in the multi-layered organic devices. Consequently, thermal annealing treatment for the 2-TNATA:C60 film is preferred rather than in situ electromagnetic field treatment so as to improve the overall performance of the organic light-emitting diodes in this study.