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Suhwei Chen - One of the best experts on this subject based on the ideXlab platform.
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AnAlysis of KAnAmycin A in humAn plAsmA And in orAl dosAge form by derivAtizAtion with 1 nAphthyl isothiocyAnAte And high performAnce liquid chromAtogrAphy
IEEE Journal of Solid-state Circuits, 2006Co-Authors: Suhwei Chen, Yichian Liang, Yuwei ChouAbstract:A simple And sensitive HPLC method hAs been developed for trAce determinAtion of KAnAmycin A by derivAtizAtion. PlAsmA proteins Are precipitAted by Acetonitrile And chemicAl derivAtizAtion is performed on the supernAtAnt contAining KAnAmycin A with 1-nAphthyl isothiocyAnAte in pyridine At 70 degrees C. After the derivAtizAtion reAction, A methylAmine/Acetonitrile solution wAs Added to the reAction mixture to eliminAte the excess of derivAtizing Agent And shorten the AnAlysis time. The resulting derivAtive wAs sepArAted using A LichrocArt Purospher STAR RP-18e column And wAter/methAnol (33:67, v/v) As A mobile phAse (detection At 230 nm). OptimizAtion conditions for the derivAtizAtion of KAnAmycin A were investigAted by HPLC. The lineAr rAnge for the quAntitAtion of KAnAmycin A in spiked plAsmA wAs over 1.2-40 microg/mL; the detection limit (signAl to noise rAtio = 3; injection volume, 10 microL) wAs About 0.3 microg/mL. The relAtive stAndArd deviAtion wAs less thAn 2.9% for intrA-dAy AssAy (n = 6) And inter-dAy AssAy (n = 6) And relAtive recoveries were found to be greAter thAn 98%. PreliminAry ApplicAtion of the method for monitoring KAnAmycin A in humAns upon intrAmusculAr injection of the injection product demonstrAted the usefulness of the AssAy for clinicAl studies. The proposed method cAn Also be used to AnAlyze the compound in phArmAceuticAl formulAtions.
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rApid And selective micellAr electrokinetic chromAtogrAphy for simultAneous determinAtion of AmikAcin KAnAmycin A And tobrAmycin with uv detection And ApplicAtion in drug formulAtions
Electrophoresis, 2005Co-Authors: Hsinhua Yeh, Suhwei Chen, Shunjin Lin, Chiaan ChouAbstract:A simple And selective micellAr electrokinetic chromAtogrAphy (MEKC) with UV detection is described for simultAneous determinAtion of AmikAcin, tobrAmycin, And KAnAmycin A, performed in Tris buffer (180 mM; pH 9.1) with 300 mM sodium pentAnesulfonAte (SPS) As An Anionic surfActAnt. Under this condition, good sepArAtion with high efficiency And the required short AnAlysis time is Achieved. The lineAr rAnges of the method for the determinAtion of AmikAcin, tobrAmycin, And KAnAmycin A were 0.1–0.5 mg / mL, 0.4–2.0 mg / mL, And 0.4–2.0 mg / mL, respectively; the detection limits (signAl-to-noise rAtio = 3; injection, 0.5 psi 5 s) were 0.08, 0.2, And 0.2 mg / mL, respectively. The smAll Amount of sAmple required And the expeditiousness of the procedure Allow content uniformity to be determined in individuAl commerciAl products.
Sidhanath V Bhosale - One of the best experts on this subject based on the ideXlab platform.
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KAnAmycin A 6 pyrenylAmide A selective probe for hepArin detection
Tetrahedron Letters, 2012Co-Authors: Santosh V Nalage, Sidhanath V Bhosale, Suresh K BhargavaAbstract:AbstrAct We hAve synthesized A novel derivAtive of KAnAmycin A beAring A pyrenyl fluorophore which cAn be used for the specific recognition of hepArin in EtOH:H2O (1:3) through formAtion of A 2:1 complex. The receptor shows specific opticAl signAlling for hepArin, but exhibits no significAnt chAnges on Addition of vArious other biologicAl molecules.
Matthew D Disney - One of the best experts on this subject based on the ideXlab platform.
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moleculAr recognition of 6 n 5 hexynoAte KAnAmycin A And rnA 1x1 internAl loops contAining cA mismAtches
Biochemistry, 2011Co-Authors: Tuan Tran, Matthew D DisneyAbstract:In our previous study to identify the RNA internAl loops thAt bind An Aminoglycoside derivAtive, we determined thAt 6'-N-5-hexynoAte KAnAmycin A prefers to bind 1x1 nucleotide internAl loops contAining C·A mismAtches. In this present study, the moleculAr recognition between A vAriety of RNAs thAt Are mutAted Around the C·A loop And the ligAnd wAs investigAted. Studies show thAt both loop nucleotides And loop closing pAirs Affect binding Affinity. Most interestingly, it wAs shown thAt there is A correlAtion between the thermodynAmic stAbility of the C·A internAl loops And ligAnd Affinity. SpecificAlly, C·A loops thAt hAd relAtively high or low stAbility bound the ligAnd most weAkly whereAs loops with intermediAte stAbility bound the ligAnd most tightly. In contrAst, there is no correlAtion between the likelihood thAt A loop forms A C-A(+) pAir At lower pH And ligAnd Affinity. It wAs Also found thAt A 1x1 nucleotide C·A loop thAt bound to the ligAnd with the highest Affinity is identicAl to the consensus site in RNAs thAt Are edited by Adenosine deAminAses Acting on RNA type 2 (ADAR2). These studies provide A detAiled investigAtion of fActors Affecting smAll molecule recognition of internAl loops contAining C·A mismAtches, which Are present in A vAriety of RNAs thAt cAuse diseAse.
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two dimensionAl combinAtoriAl screening identifies specific 6 AcylAted KAnAmycin A And 6 AcylAted neAmine rnA hAirpin interActions
Biochemistry, 2008Co-Authors: Olga Aminova, Jessica L Childsdisney, Dustin J Paul, Matthew D DisneyAbstract:Herein, we report the RNA hAirpin loops from A 6-nucleotide hAirpin librAry thAt bind 6′-AcylAted KAnAmycin A (1) And 6′-AcylAted neAmine (2) identified by 2-DimensionAl CombinAtoriAl Screening (2DCS). HAirpins selected to bind 1 hAve Kd's rAnging from 235-1035 nM, with An AverAge Kd of 618 nM. For 2, the selected hAirpins bind with Kd's rAnging from 135-2300 nM, with An AverAge Kd of 1010 nM. The selected RNA hAirpin-ligAnd interActions Are Also specific for the ligAnd thAt they were selected to bind compAred to the other ArrAyed ligAnd. For exAmple, the mixture of hAirpins selected for 1 on AverAge bind 33-fold more tightly to 1 thAn 2 while the mixtures of hAirpins selected for 2 on AverAge bind 11-fold more tightly to 2 thAn 1. SecondAry structure prediction of the selected sequences wAs completed to determine the motifs thAt eAch ligAnd binds, And the hAirpin loop preferences for 1 And 2 were computed. For 1, the preferred hAirpin loops contAin An Adenine sepArAted by At leAst two nucleotides from A cytosine, for exAmple ANNCNN (two-tAiled p-vAlue = 0.0010) And ANNNCN (two-tAiled p-vAlue <0.0001). For 2, the preferred hAirpin loops contAin both 5′GC And 5′CG steps (two-tAiled p-vAlue <0.0001). These results expAnd the informAtion AvAilAble on the RNA hAirpin loops thAt bind smAll molecules And could prove useful for tArgeting RNA.
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using selection to identify And chemicAl microArrAy to study the rnA internAl loops recognized by 6 n AcylAted KAnAmycin A
ChemBioChem, 2007Co-Authors: Matthew D Disney, Jessica L ChildsdisneyAbstract:Herein, we describe our initiAl steps towArds identifying the RNA secondAry structure motifs thAt Are recognized by smAll molecules. We selected members of An RNA 3×3 internAl loop motif librAry thAt bind KAnAmycin A, An RNA-binding Aminoglycoside Antibiotic, by using only one round of selection. A smAll internAl-loop librAry wAs chosen becAuse members Are likely to be present in other lArger, biologicAlly relevAnt RNAs. We hAve identified severAl internAl loops of vArious size And bAse composition thAt KAnAmycin A prefers to bind. The highest Affinity structures Are two 5′-UU/3′-CU 2×2 internAl loops closed by AU pAirs. Binding is specific for the selected internAl loops with the highest Affinities, since binding to the RNA cAssette used to displAy the librAry or to DNA is >150-fold weAker. EnzymAtic mApping experiments Also confirm binding of KAnAmycin A to the internAl loops. This method lAys the foundAtion for finding RNA secondAry structure elements thAt bind smAll molecules And for interrogAting fActors Affecting RNA–ligAnd interActions. InformAtion from these And subsequent studies will: 1) fAcilitAte the rAtionAl And modulAr design of drugs or probes thAt bind tArget RNAs with high Affinity, provided the secondAry structure of the tArget is known And 2) give insight into the potentiAl bystAnder RNAs thAt Aminoglycosides bind.
Malgorzata Jezowskabojczuk - One of the best experts on this subject based on the ideXlab platform.
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preferences of KAnAmycin A towArds copper ii effect of the resulting complexes on immunologicAl mediAtors production by humAn leukocytes
Journal of Inorganic Biochemistry, 2004Co-Authors: Wojciech Szczepanik, Anna Czarny, Ewa Zaczynska, Malgorzata JezowskabojczukAbstract:AbstrAct The widespreAd presence of pAthogenic bActeriA is A cAuse of permAnent demAnd for investigAting the properties of AntimicrobiAl Agents. The chemicAl bAsis of severAl toxic effects induced by Antibiotics still remAins uncleAr. Aminoglycosides, highly ototoxic And nephrotoxic drugs, Are cApAble of copper(II) ions chelAting. In this study we estAblished the Affinity of KAnAmycin A towArds copper(II), in contrAst with other metAl ions: iron(III), nickel(II), cobAlt(II) And zinc(II) by meAns of potentiometry. CirculAr dichroism spectroscopy wAs Applied to monitor the competition of copper(II) pArtition between KAnAmycin A And humAn serum Albumin. We show, thAt the drug is Able to digest Cu(II) ions from HSA to some extent And compAring the stAbility constAnts for metAl And Antibiotic with those, obtAined for the N-terminAl Asp–AlA–His–Lys (DAHK) sequence, which constitutes A copper(II) binding domAin within Albumin, we demonstrAte thAt the Cu(II)–KAnAmycin A complex formAtion is possible Also in blood plAsmA. BioAssAys And immunoAssAy were used to find out the possibility of Cu(II)–KAnAmycin A complexes to induce cytokines: tumor necrosis fActor (TNF), interferon (IFN) And interleukin-10 (IL-10) in humAn peripherAl blood leukocytes. The effect on the cytokines releAse wAs dose And time dependent And the interdependence between IL-10 And TNF stimulAtion wAs found. We report thAt Cu(II)-Aminoglycoside systems cAn Act As moderAte inducers of TNF-α, IFN-α/β And IL-10 releAsed from humAn leukocytes. We hAve Also found thAt these complexes Are non-toxic for humAn A549 cells.
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in vitro oxidAtive Activity of cupric complexes of KAnAmycin A in compArison to in vivo bActericidAl efficAcy
Journal of Inorganic Biochemistry, 2003Co-Authors: Wojciech Szczepanik, Ewa Dworniczek, Jerzy Ciesiolka, Jan Wrzesinski, Jacek Skala, Malgorzata JezowskabojczukAbstract:The interActions of copper(II) complexes of KAnAmycin A with oxidAtion-susceptible biomolecules: 2'-deoxyguAnosine, plAsmid DNA And yeAst tRNA(Phe) were studied in both the presence And Absence of hydrogen peroxide. The mixture of complex with H(2)O(2) wAs found to be An efficient oxidAnt, converting dG to its 8-oxo derivAtive, generAting strAnd breAks in plAsmid DNA And multiple cleAvAges in tRNA(Phe). Some of these reActions mAy plAy A role in toxic effects of Aminoglycoside Antibiotics. These complexes were screened for their AntibActeriAl Activity. The microbiologicAl studies undertAken to compAre the bActericidAl Action of KAnAmycin A Alone And complexed with copper(II) ions in both neutrAl And oxidAtive environment reveAled thAt the enhAncement of bActericidAl Action by Cu(II) wAs not stAtisticAlly significAnt.
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copper ii binding by KAnAmycin A And hydrogen peroxide ActivAtion by resulting complexes
New Journal of Chemistry, 2002Co-Authors: Wojciech Szczepanik, Piotr Kaczmarek, Jaroslaw M Sobczak, Wojciech Bal, Kazimierz Gatner, Malgorzata JezowskabojczukAbstract:ProtonAtion And copper(II) coordinAtion properties of KAnAmycin A were studied in solution by potentiometry, UV-Vis, circulAr dichroism (CD), EPR And cyclic voltAmmetry (CV). Only mononucleAr complexes of stoichiometries rAnging from CuH2L to CuH−2L were found. KAnAmycin A Anchors Cu(II) ions with An {NH2, O−} chelAte of the C-ring of its molecule. At pH higher thAn 6 the Amino And hydroxyl groups of the A-ring of KAnAmycin A Also pArticipAte in binding. The resulting structure, similAr to thAt of complexes of other unsubstituted Aminoglycosides studied previously, involves Cu(II) coordinAtion by donors of terminAl AminosugAr rings, rAther thAn those of the centrAl unit. The results of cyclic voltAmmetry investigAtions, kinetic studies of H2O2 disproportionAtion And ROS detection experiments, further supported the mechAnism of oxidAtive reActivity of cupric complexes of Aminoglycosides, proposed by us recently [M. JezowskA-Bojczuk, W. LeśniAk, W. BAl, H. Kozlowski, K. GAtner, A. Jezierski, J. SobczAk, S. MAngAni And W. Meyer-KlAucke; Chem. Res. Toxicol., 2001, 14, 1353–1362], which involves Cu(I) And Cu(III) redox stAtes And both metAl-bound And free ROS.
Xianda Han - One of the best experts on this subject based on the ideXlab platform.
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Two KAnAmycin electrochemicAl AptAmer-bAsed sensors using different signAl trAnsduction mechAnisms: A compArison of electrochemicAl behAvior And sensing performAnce.
Bioelectrochemistry (Amsterdam Netherlands), 2019Co-Authors: Xianda Han, Wenbing Shi, Hong Yan, Guiling ZhangAbstract:AbstrAct Two typicAl KAnAmycin-A (KAN-A) electrochemicAl AptAmer-bAsed sensors employing different signAl trAnsduction mechAnisms were deliberAtely designed And constructed with A similAr structure. One sensor (sensor-1) wAs bAsed on the clAssicAl probe conformAtion chAnging mode (PCCM) with A methylene blue (MB) lAbel used As An electrochemicAl tAg; the other sensor (sensor-2) used the tArget-induced signAl probe shifting (TISPS) method with A free MB lAbel in the AssAy solution. The difference in signAl trAnsduction mechAnisms resulted in big differences in bAsic electrochemicAl behAvior And comprehensive sensing performAnce. The results show thAt both sensor types exhibit different electrochemicAl behAvior in squAre wAve voltAmmetry, cyclic voltAmmetry, And in sensitivity, with detection limits of 3.0 nM for sensor-1 And 60.0 pM for sensor-2 in buffer. When vAlidAted for prActicAl And quAntitAtive detection of tAp wAter And milk sAmples, both sensing methods performed well with detection limits of
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A signAl on electrochemicAl AptAsensor for highly sensitive And specific detection of KAnAmycin bAsed on tArget induced signAling probe shifting mechAnism
Sensors and Actuators B-chemical, 2018Co-Authors: Xianda Han, Wenbing Shi, Hong Yan, Yan Liu, Guiling ZhangAbstract:AbstrAct An electrochemicAl displAcement-bAsed AptAsensor wAs developed for the detection of KAnAmycin-A ( KMY-A ). BAsed on the tArget-induced signAling probe shifting mechAnism, this AptAsensor shows A “signAl on” chAnge with A simple 3-probe structure. One no-thiolAted cApture probe And one thiolAted AssistAnt probe Are AttAched onto the Au electrode surfAce in A short duplex stAte, And one methylene blue ( MB )-lAbelled signAling probe is free in the detection solution. Before Adding the KMY-A , A very smAll bAckground signAl is obtAined with low efficient electron trAnsfer becAuse of the MB lAbels on the signAling probe fAr from the electrode surfAce. After Adding the KMY-A , the more stAble cApture probe/ KMY-A complex formed between the cApture probe And the KMY-A undoes the former short duplex to releAse the AssistAnt probe, which induces the formAtion of Another AssistAnt probe / signAling probe duplex. This structure chAnge cAn shift the MB lAbels close to the electrode surfAce with much higher efficient electron trAnsfer, thereby leAding to A big detection signAl. Under the optimized fAbricAtion And detection conditions, the sensor feAtures A high sensitivity for KMY-A with the detection limit of 3.3 pM And A fAst sensing speed with the response time of ∼9 min. In Addition, it is worth mentioning thAt the tArget discriminAtion Ability of sensor cAn be improved through using longer AssistAnt probe to strengthen the hybridizAtion force between the cApture probe And the AssistAnt probe, which is helpful for estAblishing the speciAl detection system with high specificity requirement.
