• Bulletin of the Korean Chemical Society
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• v.30 no.9
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• pp.1951-1955
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• 2009

A Thermodynamic study on the interaction of bovine calf thymus DNA with new designed Pd(II) complex (Ethylendiamine- 8-hydroxyquinolinato Palladium(II) chloride) was studied by using isothermal titration calorimetry (ITC) at 27 ${^{\circ}C}$ in Tris buffer solution at pH = 7.5. The enthalpies of Pd(II) complex + DNA interaction are reported and analysed in terms of the new solvation theory. It was indicated that there are three identical and non-cooperative sites for Pd(II) complex. The binding of a Pd(II) complex is endothermic with association equilibrium constants of 428.03 m$M^{-1}$ at 27 ${^{\circ}C}$. The binding of Pd(II) complex can cause some changes in the stability of the DNA at low and high Pd(II) complex concentrations. Our results suggested that this complex might interact with DNA as an intercalator, thus interfering with DNA replication and cell proliferation.

• Bulletin of the Korean Chemical Society
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• v.27 no.11
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• pp.1801-1808
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• 2006

The interaction between whey carrier protein $\beta$-lactoglobulin type A and B (BLG-A and -B) and 2,2'-bipyridin n-hexyl dithiocarbamato Pd(II) nitrate (BPHDC-Pd(II)), a new heavy metal complex designed for anticancer property, was investigated by fluorescence spectroscopy combined with chemometry and circular dichroism (CD) techniques. A strong fluorescence quenching reaction of BPHDC-Pd(II) to BLG-A and -B was observed. Hence, BPHDC-Pd(II) complex can be bound to both BLG-A and -B, and quench the fluorescence spectra of the proteins. The quenching constant was determined using the modified Stern-Volmer equation. The binding parameters were evaluated by fluorescence quenching method. The results of binding study provided evidences presence of two and three sets of binding sites on the BLG-B and -A, respectively, for BPHDC-Pd(II) complex. Using fluorescence spectroscopy and chemometry, the ability of BLG-A and -B to form an intermediate upon interaction with BPHDC-Pd(II) complex was assessed. CD studies displayed that under influence of different concentrations of BPHDC-Pd(II) complex, the regular secondary structure of BLG-B had no significant changes, whereas for BLG-A a transition from $\alpha$-helix to $\beta$-structure was appeared. The results for both of BLG-A and -B displayed that BPHDC-Pd(II) complex can induce a conformational transition from the native form to an intermediate state with a slightly opened conformation, which is detectable with chemometry analyses.

• BMB Reports
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• v.34 no.6
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• pp.551-558
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• 2001

We extended the measurable time scale of DNA dynamics to submicrosecond using a long-lifetime metal-ligand complex, $[Ru(phen)_2(dppz)]^{2+}$ (phen=1,10-phenanthroline, dppz=dipyrido[3,2-a:2',3'-c]phenazine) (RuPD), which displays a mean lifetime near 350 ns. We partially characterized the fluorescence resonance energy transfer (FRET) in calf thymus DNA from RuPD to nile blue (NB) using frequency-domain fluorometry with a high-intensity, blue light-emitting diode (LED) as the modulated light source. There was a significant overlap of the emission spectrum of the donor RuPD with the absorption spectrum of the acceptor NB. The F$\ddot{o}$rster distance ($R_0$) that was calculated from the spectral overlap was $33.4\;{\AA}$. We observed dramatic decreases in the steady-state fluorescence intensities of RuPD when the NB concentration was increased. The intensity decays of RuPD were matched the closest by a triple exponential decay. The mean decay time of RuPD in the absence of the acceptor NB was 350.7 ns. In a concentration-dependent manner, RuPD showed rapid intensity decay times upon adding NB. The mean decay time decreased to 184.6 ns at $100\;{\mu}M$ NB. The FRET efficiency values that are calculated from the mean decay times increased from 0.107 at $20\;{\mu}M$ NB to 0.474 at $100\;{\mu}M$ NB concentration. The use of FRET with a long-lifetime metal-ligand complex donor is expected to offer the opportunity to increase the information about the structure and dynamics of nucleic acids.

• Korean Journal of Crystallography
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• v.15 no.2
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• pp.74-77
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• 2004

The crystal structure of Dinitroethylenediaminepalladium(II), $Pd(C_2H_8N_2)(NO_2)_2$, has been determined by X-ray crystallography. Crystal data: a=7.425(3), b=8.480(4), c=11.885(2) ${\AA}$, Orthorhombic, $A2_1ma$ (Space Group No=36), Z=4, V=748.3(4) ${\AA}^3,\;D_c=2.295 gcm^{-3},\;{\mu}=2.457mm^{-1}$. The structure was solved by Patterson method and refined by full matrix least-square methods using unit weights. The final R and S values were $R_1=0.0306,\;R_w=0.0802,\;R_{all}=0.0320,\;and\;S=1.166)$ for the observed 377 reflections. Bond lengths and angles of palladium complex are similar to the previously reported data. The complex structure is one dimensional Reiset's salt type analogue showing zigzag chain of Pd-Pd length and angle of 3.762(2) ${\AA}$ and $161.41(5)^{\circ}$. The complex molecules are linked through inter-and intramolecular hydrogen bonds of 3.05(1) and 3.15(1) ${\AA}$ between oxygen and nitrogen.

• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1350-1360
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• 2001

The synthesis and characterization of very stable Pd(Ⅱ) η1-imine complexes of bis(3,4-dialkyloxybenzylidene-3', 4'-dialkyloxyaniline)dichloropalladium(Ⅱ) with alkyl chain of hexyl (8), octyl (9), decyl (10) and dodecyl (11) groups, a nd of bis(4-ethyloxybenzylidene-4'-ethyloxyaniline)dichloropalladium(Ⅱ) as a model complex are described. The molecular structure with twisted board-like geometry of the complex resulting from the coordination of Pd(Ⅱ) with η1-imine bonding was confirmed by X-ray crystallographic analysis of the model complex. In contrast to the imine ligands, all the complexes with an exception of 11 display a thermally stable monotropic smectic A mesophase without any decomposition of the complex. These results, characterized by a combination of differential scanning calorimetry, optical polarized microscopy, and powder X-ray scattering experiments, are discussed.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2711-2716
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• 2011

para-Substituted phenoxide derivatives of Pd(II) having an NCN pincer, Pd(NCN)($OC_6H_4$-p-X) (NCN = 2,6-$(CH_2NMe_2)_2C_6H_3$; X = $NO_2$ (1), Me (2)) were prepared by the reaction of Pd(NCN)($OSO_2CF_3$) with equi-molar amount of $NaOC_6H_4$-p-X. Treatment of Pd(NCN)($OSO_2CF_3$) with an excess amount of $NaOC_6H_4$-p-Me affords the hydrogen-bonding adduct complex 3 ($2{\cdot}HOC_6H_4$-p-Me). Complex 3 can also be obtained from benzene solution of 2 in the presence of free $HOC_6H_4$-p-Me. Complex 1 does not undergo adduct formation with $HOC_6H_4-p-NO_2$ neither from metathesis reaction of Pd(NCN)($OSO_2CF_3$) with an excess amount of $NaOC_6H_4-p-NO_2$ nor from treatment of 1 with free $HOC_6H_4-p-NO_2$. Complex 3 undergoes fast exchange of the coordinated p-cresolate with the hydrogen-bonding p-cresol. Complex 2 undergoes ${\sigma}$-ligand exchange reaction with $HOC_6H_4-p-NO_2$ to give 1. The exchange reaction, however, is irreversible as readily anticipated from their respective $pK_a$ values of the phenol derivatives. Reaction of 2 with diphenyliodium chloride quantitatively produced Pd(NCN)Cl and PhI along with liberation of O-phenylated product $PhOC_6H_4$-p-Me which was identified by GC/MS spectroscopy.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.312.2-312.2
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• 2002

The metal-ligand complex, ［Ru(phen)$_2$(dppz)]^{2＋}$ (phen = 1.10-phenanthroline, dppz = dipyrido［3.2-a:2', 3'-c］phenazine) (RuPD), was used as a spectroscopic probe for studying nucleic acid dynamics. The RuPD complex displays a long lifetime and a molecular light switch property upon DNA binding due to shielding of its dppz ligand from water. (omitted)

• Bulletin of the Korean Mathematical Society
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• v.58 no.2
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• pp.497-505
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• 2021

Let R → S be a ring homomorphism. The relations of Gorenstein projective dimension with respect to a semidualizing module of homologically bounded complexes between U ⊗LR X and X are considered, where X is an R-complex and U is an S-complex. Some sufficient conditions are given under which the equality ${\mathcal{GP}}_{\tilde{C}}-pd_S(S{\otimes}{L \atop R}X)={\mathcal{GP}}_C-pd_R(X)$ holds. As an application it is shown that the Auslander-Buchsbaum formula holds for GC-projective dimension.

• Clinical and Experimental Pediatrics
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• v.60 no.4
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• pp.106-111
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• 2017

Purpose: This study aimed to determine the prevalence of glucose-6-phosphate dehydrogenase (G6PD) deficiency among infants with neonatal indirect hyperbilirubinemia (NIH); compare G6PD-deficient and G6PD-normal patients regarding hyperbilirubinemia and need for exchange transfusions (ET); and assess risk factors for ET and kernicterus. Methods: This is a case-control retrospective study. Medical records of NIH patients admitted to the Pediatric Department, Salmaniya Medical Complex, Bahrain, between January 2007 and June 2010 were reviewed. Data on sex, age at presentation, hospitalization duration, need for ET, hemoglobin (Hb) level, reticulocyte count, direct Coombs test, serum total and indirect bilirubin levels, thyroid function, blood and urine cultures, G6PD status, and blood groups were collected and compared between the G6PD-deficent and G6PD-normal patients. Results: Of 1,159 NIH patients admitted, 1,129 were included, of whom 646 (57%) were male. Among 1,046 patients tested, 442 (42%) were G6PD deficient, 49 (4%) needed ET, and 11 (1%) had suspected Kernicterus. The G6PD-deficient patients were mainly male (P<0.0001), and had lower Hb levels (P<0.0001) and higher maximum bilirubin levels (P=0.001). More G6PD-deficient patients needed ET (P<0.0001). G6PD deficiency (P=0.006), lower Hb level (P=0.002), lower hematocrit count (P=0.02), higher bilirubin level (P<0.0001), higher maximal bilirubin level (P<0.0001), and positive blood culture result (P<0.0001) were significant risk factors for ET. Maximal bilirubin level was a significant risk factor for kernicterus (P=0.021) and independently related to ET (P=0.03). Conclusion: G6PD deficiency is an important risk factor for severe NIH. In G6PD-deficent neonates, management of NIH should be hastened to avoid irreversible neurological complications.

• Bulletin of the Korean Chemical Society
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• v.29 no.12
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• pp.2533-2536
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• 2008