当前位置： SCI文献检索 > JOURNAL OF INORGANIC BIOCHEMISTRY期刊下所有文献 > Rapid non-equilibrium aluminium-ligand interactions: studies on the precipitation of aluminium by laser light scattering, ultrafiltration and centrifugation.

Rapid non-equilibrium aluminium-ligand interactions: studies on the precipitation of aluminium by laser light scattering, ultrafiltration and centrifugation.

Abstract：

:The study aimed to develop simple assays to study aluminium-ligand interactions in natural/biological systems where equilibrium is rarely reached and thus where the initial seconds or hours of interactions are important. The immediate and non-equilibrium precipitation of aluminium hydroxide, in aqueous solution at neutral pH, was therefore studied by laser light scattering (diffraction), ultrafiltration and centrifugation. The interaction of weak ligands, present in the gastrointestinal lumen, on the precipitation of aluminium hydroxide was also investigated. The initial kinetics and particle sizes of precipitated aluminium hydroxide were sensitive to a number of external factors, including the presence of weak ligand (bicarbonate), sheer force (stirring), electrolyte concentration and initial (i.e. added) aluminium concentration. However, after a few seconds (no weak ligand), or several hundred seconds (with weak ligand), the subsequent observed changes to the solid phase were of small magnitude and occurred slowly. Thus, a 25-min window, within 5 and 30 min of pH adjustment, can be used to study the interactions of aluminium-ligand. This may approximate better to most natural systems where unperturbed aluminium-ligand equilibrium must rarely exist.

journal_name

J Inorg Biochem

journal_title

Journal of inorganic biochemistry

authors

Jugdaohsingh R,Salim N,McCrohan CR,White KN,Thompson RP,Powell JJ

doi

10.1016/s0162-0134(01)00311-7

subject

Has Abstract

pub_date

2001-11-01 00:00:00

pages

29-35

issue

1-2

eissn

0162-0134

issn

1873-3344

pii

S0162-0134(01)00311-7

journal_volume

87

pub_type

杂志文章

相关文献

JOURNAL OF INORGANIC BIOCHEMISTRY文献大全
  • Metal complexes of anhydrotetracycline. 2. Absorption and circular dichroism study of Mg(II), Al(III), and Fe(III) complexes. Possible influence of the Mg(II) complex on the toxic side effects of tetracycline.

    abstract：:Anhydrotetracycline (AHTC) is the major toxic decomposition product of the antibiotic tetracycline. The complexation of AHTC to Mg(II), Al(III), and Fe(III) was studied in aqueous medium using absorption and circular dichroism measurements. The study of the Mg(II)-AHTC interactions at pH 7 indicated the formation of t...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/0162-0134(95)00017-i

    authors： Machado FC,Demicheli C,Garnier-Suillerot A,Beraldo H

    更新日期：1995-11-15 00:00:00

  • Enantioselective DNA condensation induced by heptameric lanthanum helical supramolecular enantiomers.

    abstract：:DNA condensation induced by a pair of heptameric La(III) helical enantiomers M-[La7(S-L)6(CO3)(NO3)6(OCH3)(CH3OH)7]·2CH3OH·5H2O and P-[La7(R-L)6(CO3)(NO3)6(OCH3)(CH3OH)5(H2O)2]·2CH3OH·4H2O (M-La and P-La, L=2-(2-hydroxybenzylamino)-3-carbamoylpropanoic acid) has been investigated by UV/vis spectroscopy, fluorescence s...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2014.05.001

    authors： Bao FF,Xu XX,Zhou W,Pang CY,Li Z,Gu ZG

    更新日期：2014-09-01 00:00:00

  • Kinetic studies on the reaction between Trametes villosa laccase and dioxygen.

    abstract：:A laccase from the fungus Trametes villosa (TviL) was investigated in order to elucidate the reaction mechanism of the reduction of dioxygen to water performed by this blue multi-copper oxidase. The ability of TviL to activate dioxygen was studied by stopped-flow experiments and under steady-state conditions. In the s...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2006.05.007

    authors： Bukh C,Lund M,Bjerrum MJ

    更新日期：2006-09-01 00:00:00

  • Controlled self-assembling structures of ferrocene-dipeptide conjugates composed of Ala-Pro-NHCH2CH2SH chain.

    abstract：:Bioorganometallic ferrocene-dipeptide conjugates with the Ala-Pro-cysteamine chain, Fc-L-Ala-L-Pro-NHCH2CH2SH (2) and Fc-L-Ala-D-Pro-NHCH2CH2SH (4) (Fc=ferrocenoyl), were prepared by the reduction of the ferrocene-dipeptide conjugates, Fc-L-Ala-L-Pro-cystamine-L-Pro-L-Ala-Fc (1) or Fc-L-Ala-D-Pro-cystamine-D-Pro-L-Ala...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2017.05.009

    authors： Moriuchi T,Nishiyama T,Tayano Y,Hirao T

    更新日期：2017-12-01 00:00:00

  • Terpyridine-platinum(II) complexes are effective inhibitors of mammalian topoisomerases and human thioredoxin reductase 1.

    abstract：:Terpyridine-platinum(II) (TP-Pt(II)) complexes are known to possess DNA-intercalating activity and have been regarded as potential antitumor agents. However, their cytotoxic mechanism remains unclear. To investigate the possible mechanism, a series of TP-Pt(II) compounds were prepared and their biological activities a...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2009.05.006

    authors： Lo YC,Ko TP,Su WC,Su TL,Wang AH

    更新日期：2009-07-01 00:00:00

  • Synthesis, characterization, and binding affinity of hydrosulfide complexes of synthetic iron(II) porphyrinates.

    abstract：:The binding and reactivity of the hydrosulfide ion (HS-) to iron(II) porphyrinates has been examined for several synthetic meso-tetraphenylporphine (TPP) derivatives. In all cases, HS- coordinates to the iron centers in a 1:1 stoichiometry with formation constants (Kf) that reflect the electronic characteristics of th...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2016.08.014

    authors： Meininger DJ,Arman HD,Tonzetich ZJ

    更新日期：2017-02-01 00:00:00

  • Reversible inactivation of cytochrome P450 by alkaline earth metal ions: auxiliary metal ion induced conformation change and formation of inactive P420 species in CYP101.

    abstract：:The effects of the divalent alkaline-earth metal ions (Ca2+ and Mg2+) on the substrate binding affinity, spin-state transition at the heme active site, conformational properties as well as the stability of the active form of cytochrome P450cam (CYP 101) have been investigated using various spectroscopic and kinetic me...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2008.01.013

    authors： Manna SK,Mazumdar S

    更新日期：2008-05-01 00:00:00

  • O2-binding to heme: electronic structure and spectrum of oxyheme, studied by multiconfigurational methods.

    abstract：:We have studied the ground state of a realistic model of oxyheme with multiconfigurational second-order perturbation theory (CASPT2). Our results show that the ground-state electronic structure is strongly multiconfigurational in character. Thus, the wavefunction is a mixture of many different configurations, of which...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2004.11.008

    authors： Jensen KP,Roos BO,Ryde U

    更新日期：2005-01-01 00:00:00

  • New platinum(II)-bipyridyl corrole complexes: Synthesis, characterization and binding studies with DNA and HSA.

    abstract：:A simple methodology giving access to the metal-free corroles of trans-A2B type, 5,15-bis(pentafluorophenyl)-10-{3-[2-(pyridin-4-yl)vinyl]phenyl}corrole and 5,15-bis(pentafluorophenyl)-10-{4-[2-(pyridin-4-yl)vinyl]phenyl}corrole, and to the corresponding bipyridyl platinum(II) complexes is described. These new positio...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2015.08.016

    authors： Iglesias BA,Barata JFB,Pereira PMR,Girão H,Fernandes R,Tomé JPC,Neves MGPMS,Cavaleiro JAS

    更新日期：2015-12-01 00:00:00

  • A role for cyclic hydroxamates in aluminium resistance in maize?

    abstract：:Hydroxamate siderophores have been found to alleviate Al toxicity in bacteria. In Poaceae plants cyclic hydroxamates, like DIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one) and its derivatives have mostly been studied in relation to either defence against insects or allelopathy. In this study the influence of Al o...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2005.05.017

    authors： Poschenrieder C,Tolrà RP,Barceló J

    更新日期：2005-09-01 00:00:00

  • Application of tris(2,2'-bipyridyl)ruthenium(III) for the investigation of DNA spatial structure by a chemical modification method.

    abstract：:It was shown that the treatment of a DNA fragment and a hepta-decanucleotide having a hairpin structure by Ru(2,2'-bipyridyl)3(3+) complex at 15 degrees C in 1 M NaCl for 10-60 min, and subsequent hydrolysis in 1 M piperidine at 95 degrees C led to the specific cleavage of the polynucleotide chain at guanosine residue...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/0162-0134(88)85025-6

    authors： Fedorova OS,Podust LM

    更新日期：1988-11-01 00:00:00

  • Design of silk proteins with increased heme binding capacity and fabrication of silk-heme materials.

    abstract：:In our previous studies, heme was bound into honeybee silk to generate materials that could function as nitric oxide sensors or as recoverable heterogeneous biocatalysts. In this study, we sought to increase the heme-binding capacity of the silk protein by firstly redesigning the heme binding site to contain histidine...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2017.08.031

    authors： Rapson TD,Liu JW,Sriskantha A,Musameh M,Dunn CJ,Church JS,Woodhead A,Warden AC,Riley MJ,Harmer JR,Noble CJ,Sutherland TD

    更新日期：2017-12-01 00:00:00

  • Modulation of relaxation activity of human topoisomerases by Pt(II)-based complexes.

    abstract：:The clinical efficiency of Pt(II)-based drugs is founded on articulate mechanisms of action. Indeed it depends on a balanced combination of metal ion reactivity towards proteins and nucleic acids. Here we analysed the effect of two trans-platinum planar amines in comparison to cisplatin and transplatin on the DNA proc...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2020.111178

    authors： Pinato O,Benettazzo A,Dalla Via L,Farrell NP,Sissi C

    更新日期：2020-10-01 00:00:00

  • Cis- and trans-conformations for peroxynitrite anions.

    abstract：:The biochemically important anion, peroxynitrite, is commonly thought to have a cis-conformation which is stable. This is thought to have a cyclic structure, which blocks the formation of the trans-conformation. Furthermore, it is often suggested that the latter structure isomerises to the far more stable nitrate ion....

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/s0162-0134(00)00057-x

    authors： Symons MC

    更新日期：2000-03-01 00:00:00

  • In-vivo evaluation of the response of Galleria mellonella larvae to novel copper(II) phenanthroline-phenazine complexes.

    abstract：:Herein we report the in-vivo characterisation and metabolic changes in Galleria mellonella larvae to a series of bis-chelate copper(II) phenanthroline-phenazine cationic complexes of [Cu(phen)2]2+ (Cu-Phen), [Cu(DPQ)(Phen)]2+ (Cu-DPQ-Phen) and [Cu(DPPZ)(Phen)]2+ (Cu-DPPZ-Phen) (where phen = 1,10-phenanthroline, DPQ = ...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2018.05.020

    authors： Rochford G,Molphy Z,Browne N,Surlis C,Devereux M,McCann M,Kellett A,Howe O,Kavanagh K

    更新日期：2018-09-01 00:00:00

  • A molecular cytogenetic approach to studying platinum resistance.

    abstract：:The technique of comparative genomic hybridisation (CGH) has until recently been used to screen for common genomic abnormalities in fresh tumour material; it has identified previously unrecognised regions of amplification associated with poor prognosis subtypes of breast cancer and lymphoma. Our group has applied this...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/s0162-0134(99)00140-3

    authors： Hiorns LR,Seckl MJ,Paradinas F,Sharp SY,Skelton LA,Brunstrom G,Newlands ES,Kelland LR,Leyland-Jones B

    更新日期：1999-10-01 00:00:00

  • Kinetics of chromium(V) formation and reduction in fronds of the duckweed Spirodela polyrhiza--a low frequency EPR study.

    abstract：:The uptake of chromate by the duckweed Spirodela polyrhiza was investigated with atomic absorption spectroscopy and the reduction of Cr(VI) to Cr(V) was measured using low frequency EPR spectroscopy. The biphasic kinetics of the uptake was fitted to parameters of a proposed kinetic model. Another model was developed t...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/s0162-0134(00)00018-0

    authors： Appenroth KJ,Bischoff M,Gabryś H,Stoeckel J,Swartz HM,Walczak T,Winnefeld K

    更新日期：2000-02-01 00:00:00

  • Dioxygen affinities and catalytic oxidation activities of cobalt complexes with Schiff bases containing crown ether.

    abstract：:The stoichiometry of dioxygen uptake of Co complexes with 4',5'-bis-(5-chloro-2-hydroxyphenylmethylideneimino)benzo-12-crown-4 (1a), 4',5'-bis(2-hydroxyphenylmethylideneimino)benzo-12-crown-4 (1b), 4',5'-bis-(5-methoxy-2-hydroxyphenylmethylideneimino)benzo-12-crown-4 (1c), 4',5'-bis-(5-chloro-2-hydroxyphenylmethyliden...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2006.03.004

    authors： Sun B,Chen J,Hu J,Li X

    更新日期：2006-08-01 00:00:00

  • Synthesis and antitumor activity of platinum(II) complexes with trans-3,4-diamino-2,2,6,6-tetramethylpiperidine-1-oxyl.

    abstract：:Platinum complexes PtII(DAPO)X2 with diaminonitroxyl radical-trans-3,4-diamino-2,2,6,6-tetramethylpiperidine-1-oxyl (DAPO)-were synthesized by the direct reaction of DAPO with K2PtX4 (X = Cl, I) or by the replacement of chloro ligands in PtII(DAPO)Cl2 by bromo, nitrato, oxalato, malonato, and 1,1-cyclobutanedicarboxyl...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/0162-0134(96)00029-3

    authors： Sen' VD,Golubev VA,Volkova LM,Konovalova NP

    更新日期：1996-10-01 00:00:00

  • Gold(I)-NHC complexes of antitumoral diarylimidazoles: structures, cellular uptake routes and anticancer activities.

    abstract：:Five new heterocyclic gold carbene complexes were prepared, four chlorido-[1,3-dimethyl-4,5-diarylimidazol-2-ylidene]gold complexes 6a-d and a chlorido-[1,3-dibenzylimidazol-2-ylidene]gold complex 11, and three of them were characterised by X-ray single crystal analyses. They were tested for cytotoxicity against a pan...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2011.08.026

    authors： Kaps L,Biersack B,Müller-Bunz H,Mahal K,Münzner J,Tacke M,Mueller T,Schobert R

    更新日期：2012-01-01 00:00:00

  • Lathyrus cicera copper amine oxidase reactions with tryptamine.

    abstract：:Lathyrus cicera copper amine oxidase (LCAO) rapidly formed the typical Cu(I)-TPQ semiquinone UV-visible spectrum, identical to that formed by other substrates, upon O(2) exhaustion by turnover with excess tryptamine. A new band at 630 nm formed more slowly, with intensity dependent on aldehyde and H(2)O(2) concentrati...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2012.01.002

    authors： Pietrangeli P,Bellelli A,Fattibene P,Mondovì B,Morpurgo L

    更新日期：2012-04-01 00:00:00

  • Effect of tunable redox behavior of bis chelate substituted 1,10-phenantroline Cu(II) complexes on its reaction with superoxide anion in DMSO. Toward a simple criterion to identify a SOD-like mechanism.

    abstract：:In this work we report a series of Cu(II) complexes [Cu(N-N)2(X)]+, (N-N=substituted 1,10-phenanthroline derivatives and X=Cl- or NO3-), with tunable E1/2 for electrochemical reduction [CuII(N-N)2(X)]++1e-⇌[CuI(N-N)2]+X-. The disproportion of O2•- was explored in presence of the electro-generated species [CuI(N-N)2]+ ...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2017.07.013

    authors： Manzanera-Estrada ME,Cruz-Ramírez M,Flores-Alamo M,Gracia Y Jiménez JM,Galindo-Murillo R,García-Ramos JC,Ruiz-Azuara L,Ortiz-Frade L

    更新日期：2017-10-01 00:00:00

  • Inhibition of the GDP/GTP exchange reaction of ras p21 by aluminum ion.

    abstract：:In an effort to understand the biochemical mechanisms of aluminum-induced neurotoxicity, we investigated the effects of aluminum ion, Al3+, on the Mg(2+)- and nucleotide-dependent protein, ras p21. Picomolar Al3+ concentrations inhibited the GTPase activity of ras p21 in an Mg(2+)-dependent manner, consistent with an ...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/s0162-0134(96)00188-2

    authors： Landino LM,Macdonald TL

    更新日期：1997-05-01 00:00:00

  • Copper(I) interaction with model peptides of WD6 and TM6 domains of Wilson ATPase: regulatory and mechanistic implications.

    abstract：:With the aim to investigate the mechanism of Cu(I) transport by Wilson ATPase (ATP7B), we have studied the interaction of the peptides 2K10p (CH(3)CO-Lys-Gly-Met-Thr-Cys-Ala-Ser-Cys-Val-His-Asn-Lys-CONH(2)), and 2K8p (CH(3)CO-Lys-Leu-Cys-Ile-Ala-Cys-Pro-Cys-Ser-Lys-CONH(2)), part of the sixth metal binding domain (WD6...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2004.05.013

    authors： Myari A,Hadjiliadis N,Fatemi N,Sarkar B

    更新日期：2004-09-01 00:00:00

  • Triphenyltin(IV) benzoates with diazenyl/imino scaffold exhibiting remarkable apoptosis mediated by reactive oxygen species.

    abstract：:The cytotoxic potency of a series of triphenyltin(IV) compounds of general composition [Ph3Sn(Ln)] (1-6) has been probed in vitro employing MDA-MB-231 (human breast cancer) and HeLa (human cervical cancer) cell lines, where Ln=L1-3; isomeric 2/3/4-{(E)-2-[4-(dimethylamino)phenyl]diazenyl}benzoates and L4-6 are their c...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2017.04.020

    authors： Basu Baul TS,Dutta D,Duthie A,Prasad R,Rana NK,Koch B,Tiekink ERT

    更新日期：2017-08-01 00:00:00

  • Platinum(II) and palladium(II) complexes with (N,N') and (C,N,N')- ligands derived from pyrazole as anticancer and antimalarial agents: synthesis, characterization and in vitro activities.

    abstract：:The study of the reactivity of three 1-(2-dimethylaminoethyl)-1H-pyrazole derivatives of general formula [1-(CH(2))(2)NMe(2)}-3,5-R(2)-pzol] {where pzol represents pyrazole and R=H (1a), Me (1b) or Ph (1c)} with [MCl(2)(DMSO)(2)] (M=Pt or Pd) under different experimental conditions allowed us to isolate and characteri...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2011.09.021

    authors： Quirante J,Ruiz D,Gonzalez A,López C,Cascante M,Cortés R,Messeguer R,Calvis C,Baldomà L,Pascual A,Guérardel Y,Pradines B,Font-Bardía M,Calvet T,Biot C

    更新日期：2011-12-01 00:00:00

  • 3D-QSAR study for DNA cleavage proteins with a potential anti-tumor ATCUN-like motif.

    abstract：:Genomics projects have elucidated several genes that encode protein sequences. Subsequently, the advent of the proteomics age has enabled the synthesis and 3D structure determination for these protein sequences. Some of these proteins incorporate metal atoms but it is often not known whether they are metal-binding pro...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2006.02.019

    authors： González-Díaz H,Sánchez-González A,González-Díaz Y

    更新日期：2006-07-01 00:00:00

  • Response and tolerance of root border cells to aluminum toxicity in soybean seedlings.

    abstract：:Root border cells (RBCs) and their secreted mucilage are suggested to participate in the resistance against toxic metal cations, including aluminum (Al), in the rhizosphere. However, the mechanisms by which the individual cell populations respond to Al and their role in Al resistance still remain unclear. In this rese...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/j.jinorgbio.2011.04.004

    authors： Cai MZ,Wang FM,Li RF,Zhang SN,Wang N,Xu GD

    更新日期：2011-07-01 00:00:00

  • Iron uptake by ferritin: NMR relaxometry studies at low iron loads.

    abstract：:Twenty ferritin samples were prepared at pH 6.5 with average loadings of 0-89 Fe atoms per molecule. Nuclear magnetic relaxation times T1 and T2 were measured at 3 degrees C, 23 degrees C, and at 37 degrees C and at field strength from 0.025 to 1.5 T. The field dependence, temperature dependence, and approximate equal...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/s0162-0134(98)10047-8

    authors： Vymazal J,Brooks RA,Bulte JW,Gordon D,Aisen P

    更新日期：1998-09-01 00:00:00

  • Synthesis, characterization, and antibacterial activity of novel Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) complexes with vitamin K3-thiosemicarbazone.

    abstract：:Vitamin K3-thiosemicarbazone (C12H11N3NaO4S2 x 5H2O, abbreviated as VT), a new Schiff base derivative, has been synthesized. Its crystal structure, determined by X-ray diffraction, is triclinic, space group P1. We have also prepared five novel complexes of VT with transition metals: [M(VT)(2)2H2O] x nH2O, (n = 1 and 2...

    journal_title：Journal of inorganic biochemistry

    pub_type： 杂志文章

    doi：10.1016/s0162-0134(99)00226-3

    authors： Li QX,Tang HA,Li YZ,Wang M,Wang LF,Xia CG

    更新日期：2000-01-30 00:00:00