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1.
medRxiv ; 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38496479

RESUMEN

Inflammatory syndromes, including those caused by infection, are a major cause of hospital admissions among children and are often misdiagnosed because of a lack of advanced molecular diagnostic tools. In this study, we explored the utility of circulating cell-free RNA (cfRNA) in plasma as an analyte for the differential diagnosis and characterization of pediatric inflammatory syndromes. We profiled cfRNA in 370 plasma samples from pediatric patients with a range of inflammatory conditions, including Kawasaki disease (KD), Multisystem Inflammatory Syndrome in Children (MIS-C), viral infections and bacterial infections. We developed machine learning models based on these cfRNA profiles, which effectively differentiated KD from MIS-C - two conditions presenting with overlapping symptoms - with high performance (Test Area Under the Curve (AUC) = 0.97). We further extended this methodology into a multiclass machine learning framework that achieved 81% accuracy in distinguishing among KD, MIS-C, viral, and bacterial infections. We further demonstrated that cfRNA profiles can be used to quantify injury to specific tissues and organs, including the liver, heart, endothelium, nervous system, and the upper respiratory tract. Overall, this study identified cfRNA as a versatile analyte for the differential diagnosis and characterization of a wide range of pediatric inflammatory syndromes.

2.
Acta Crystallogr E Crystallogr Commun ; 77(Pt 6): 677-680, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34164151

RESUMEN

The crystal structure of the new double CuII complex salt, [Cu(L)(H2O)2][Cu(L)]Br4·2H2O (L = 3,14-diethyl-2,6,13,17-tetra-aza-tri-cyclo-[16.4.0.07,12]docosane, C22H44N4) has been determined using synchrotron radiation. The asymmetric unit contains one half of a [Cu(L)(H2O)2]2+ cation, one half of a [Cu(L)]2+ cation (both completed by crystallographic inversion symmetry), two bromide anions and one water solvent mol-ecule. The CuII atom in the first complex exists in a tetra-gonally distorted octa-hedral environment with the four N atoms of the macrocyclic ligand in equatorial and two aqua ligands in axial positions, whereas the CuII atom in the second complex exists in a square-planar environment defined by the four nitro-gen atoms of the macrocyclic ligand. The two macrocyclic rings adopt the most stable trans-III configuration with normal Cu-N bond lengths from 2.016 (3) to 2.055 (3) Šand an axial Cu-O bond length of 2.658 (4) Å. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the macrocycle N-H or C-H groups and the O-H groups of water mol-ecules as donor groups, and the O atoms of water mol-ecules and bromide anions as acceptor groups, giving rise to a one-dimensional network extending parallel to [100].

3.
Acta Crystallogr E Crystallogr Commun ; 77(Pt 5): 551-554, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34026263

RESUMEN

The crystal structure of the title salt, C20H42N4 2+·2ClO4 -, has been determined using synchrotron radiation at 220 (2) K. The structure determination reveals that protonation has occurred at diagonally opposite amine N atoms. The asymmetric unit comprises one half of the organic dication, which lies about a center of inversion, and one perchlorate anion. The macrocyclic dication adopts the most stable endodentate trans-III conformation. The crystal structure is stabilized by intra-molecular N-H⋯N, and inter-molecular N-H⋯O and C-H⋯O hydrogen bonds involving the macrocycle N-H and C-H groups as donors and the O atoms of perchlorate anions as acceptors, giving rise to a three-dimensional network.

4.
Acta Crystallogr E Crystallogr Commun ; 77(Pt 5): 569-572, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34026267

RESUMEN

The crystal structure of the novel hydrated CuII salt, [Cu(L)(H2O)2]Cl2·4H2O (L = 3,14-diethyl-2,6,13,17-tetra-aza-tri-cyclo-[16.4.0.07,12]docosane, C22H44N4) has been determined using synchrotron radiation. The asymmetric unit contains one half of the [Cu(L)(H2O)2]2+ cation (completed by crystallographic inversion symmetry), one chloride anion and two lattice water mol-ecules. The copper(II) atom exists in a tetra-gonally distorted octa-hedral environment with the four N atoms of the macrocyclic ligand in equatorial and two O atoms from water mol-ecules in axial positions. The latter exhibit a long axial Cu-O bond length of 2.7866 (16) Šdue to the Jahn-Teller distortion. The macrocyclic ring adopts a stable trans-III conformation with typical Cu-N bond lengths of 2.0240 (11) and 2.0441 (3) Å. The complex is stabilized by hydrogen bonds formed between the O atoms of coordinated water mol-ecules and the NH groups as donors, and chloride anions as acceptors. The chloride anions are further connected to the lattice water solvent molecules through O-H⋯Cl hydrogen bonds, giving rise to a three-dimensional network structure.

5.
Acta Crystallogr E Crystallogr Commun ; 77(Pt 3): 222-225, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33953940

RESUMEN

The crystal structure of the title complex, cis-[Cr(NCS)2(cyclam)]Br (cyclam = 1,4,8,11-tetra-aza-cyclo-tetra-decane, C10H24N4), has been determined from synchrotron X-ray data. The asymmetric unit contains one [Cr(NCS)2(cyclam)]+ cation and one bromide anion. The CrIII ion of the complex cation is coordinated by the four N atoms of the cyclam ligand and by two N-coordinating NCS groups in a cis arrangement, displaying a distorted octa-hedral coordination sphere. The Cr-N(cyclam) bond lengths are in the range 2.075 (3) to 2.081 (3) Šwhile the average Cr-N(NCS) bond length is 1.996 (16) Å. The macrocyclic cyclam moiety adopts the most stable cis-V conformation. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the cyclam N-H groups as donor groups, and the bromide anion and the S atom of one of the NCS ligands as acceptor groups.

6.
Acta Crystallogr E Crystallogr Commun ; 77(Pt 2): 213-216, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33614157

RESUMEN

The crystal structure of the hydrated title salt, C22H48N4 4+·4Cl-·4H2O (C22H48N4 = H4 L = 3,14-diethyl-2,6,13,17-tetra-azoniatri-cyclo-[16.4.0.07,12]doco-sa-ne), has been determined using synchrotron radiation at 220 K. The structure determination reveals that protonation has occurred at all four amine N atoms. The asymmetric unit comprises one half of the macrocyclic cation (completed by crystallographic inversion symmetry), two chloride anions and two water mol-ecules. The macrocyclic ring of the tetra-cation adopts an exodentate (3,4,3,4)-D conformation. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the macrocycle N-H groups and water O-H groups as donors, and the O atoms of the water mol-ecules and chloride anions as acceptors, giving rise to a three-dimensional network.

7.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 5): 656-659, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32431927

RESUMEN

The structure of the title compound, [CrCl2(C10H24N4)][Cr(HCONH2)2(C10H24N4)][ZnCl4]2 (C10H24N4 = 1,4,8,11-tetra-aza-cyclo-tetra-decane, cyclam; HCONH2 = formamide, fa), has been determined from synchrotron X-ray data. The asymmetric unit contains two independent halves of the [CrCl2(cyclam)]+ and [Cr(fa)(cyclam)]3+ cations, and one tetra-chlorido-zincate anion. In each complex cation, the CrIII ion is coordinated by the four N atoms of the cyclam ligand in the equatorial plane and two Cl ligands or two O-bonded formamide mol-ecules in a trans axial arrangement, displaying a distorted octa-hedral geometry with crystallographic inversion symmetry. The Cr-N(cyclam) bond lengths are in the range 2.061 (2) to 2.074 (2) Å, while the Cr-Cl and Cr-O(fa) bond distances are 2.3194 (7) and 1.9953 (19) Å, respectively. The macrocyclic cyclam moieties adopt the centrosymmetric trans-III conformation with six- and five-membered chelate rings in chair and gauche conformations. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the NH or CH groups of cyclam and the NH2 group of coordinated formamide as donors, and Cl atoms of the ZnCl4 2- anion as acceptors.

8.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 4): 523-526, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32280497

RESUMEN

The crystal structure of title compound, (C14H36N4)[CrO3Cl]2Cl2, has been determined by synchrotron radiation X-ray crystallography at 220 K. The macrocyclic cation lies across a crystallographic inversion center and hence the asymmetric unit contains one half of the organic cation, one chloro-chromate anion and one chloride anion. Both the Cl- anion and chloro-chromate Cl atom are involved in hydrogen bonding. In the crystal, hydrogen bonds involving the 1,4,8,11-tetra-methyl-1,4,8,11-tetra-azonia-cyclo-tetra-decane (TMC) N-H groups and C-H groups as donor groups and three O atoms of the chloro-chromate and the chloride anion as acceptor groups link the components, giving rise to a three-dimensional network.

9.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 3): 324-327, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148869

RESUMEN

The crystal structure of title salt, C14H36N4 4+·2ClO4 -·2Cl-, has been determined using synchrotron radiation at 220 K. The structure determination reveals that protonation has occurred at all four amine N atoms. The asymmetric unit contains one half-cation (completed by crystallographic inversion symmetry), one perchlorate anion and one chloride anion. A distortion of the perchlorate anion is due to its involvement in hydrogen-bonding inter-actions with the cations. The crystal structure is consolidated by inter-molecular hydrogen bonds involving the 1,4,8,11-tetra-methyl-1,4,8,11-tetra-azonia-cyclo-tetra-decane N-H and C-H groups as donor groups, and the O atoms of the perchlorate and chloride anion as acceptor groups, giving rise to a three-dimensional network.

10.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 6): 921-924, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31391995

RESUMEN

The crystal structure of title salt, C22H46N4 2+·2NO3 -·2H2O, has been determined using synchrotron radiation at 220 K. The structure determination reveals that protonation has occurred at diagonally opposite amine N atoms. The asymmetric unit contains half a centrosymmetric dication, one nitrate anion and one water mol-ecule. The mol-ecular dication, C22H46N4 2+, together with the nitrate anion and hydrate water mol-ecule are involved in an extensive range of hydrogen bonds. The mol-ecule is stabilized, as is the conformation of the dication, by forming inter-molecular N-H⋯O, O-H⋯O, together with intra-molecular N-H⋯N hydrogen bonds.

11.
Acta Crystallogr C Struct Chem ; 75(Pt 6): 616-622, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31166912

RESUMEN

Cyclam derivatives and their metal complexes have been found to exhibit an anti-HIV effect and stimulate the activity of stem cells from bone marrow. The strength of their binding to the CXCR4 receptor correlates with anti-HIV and stem-cell activities. Knowledge of the conformation and crystal packing of various macrocyclic metal complexes has become important in developing new effective anti-HIV drugs. The synthesis and preparation of single crystals of a new Cu2+-doped macrocyclic compound, (3,14-diethyl-2,6,13,17-tetraazatricyclo[16.4.0.07,12]docosane)copper(II) bis(perchlorate)-3,14-diethyl-2,13-diaza-6,17-diazoniatricyclo[16.4.0.07,12]docosane bis(perchlorate) (0.69/0.31), {[Cu(C22H44N4)](ClO4)2}0.69·(C22H46N42+·2ClO4-)0.31, is reported. Characterization by X-ray diffraction analysis shows that the asymmetric unit contains half of a centrosymmetric molecule. The macrocyclic ligand in the compound adopts the most stable trans-III conformation. The Cu-N distances of 2.015 (3) and 2.047 (3) Šare normal, but the long axial Cu-O bond of 2.795 (3) Šmay be due to a combination of the Jahn-Teller effect and the strong in-plane ligand field. The crystal structure is stabilized by hydrogen bonding between secondary N-H groups, the N atoms of the macrocycle and the O atoms of the perchlorate anions. Hirshfeld surface analysis with 2D (two-dimensional) fingerprint plots indicates that the main contributions to the crystal packing are from H...H (58.0%) and H...O/O...H (41.9%) interactions. Electron paramagnetic resonance (EPR) properties are also described.

12.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 4): 428-431, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31161050

RESUMEN

The structure of the title compound, [Cr(tacn)2]2[ZnCl4]3·H2O (tacn is 1,4,7-tri-aza-cyclo-nonane; C6H15N3), has been determined from synchrotron X-ray data. Each CrIII cation is coordinated by the six N atoms from the two tacn ligands, displaying a distorted octa-hedral geometry. Three distorted tetra-hedral [ZnCl4]2- anions and one lattice water mol-ecule lie outside this coordination sphere. The Cr-N bond lengths are in the range 2.0621 (11) to 2.0851 (12) Å, while the mean inner N-Cr-N bond angle is 82.51 (5)°. The crystal packing is stabilized by hydrogen-bonding inter-actions with the N-H groups of the tacn ligands and the water O-H groups acting as donors, and the O atoms of the water mol-ecules and Cl atoms of the [ZnCl4]2- anions as acceptors. Overall these contacts lead to the formation of a three-dimensional network.

13.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 8): 1039-1041, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-30116557

RESUMEN

The crystal structure of the title salt, C20H44N44+·4Cl-·4H2O, has been determined using synchrotron radiation at 220 K. The structure determination reveals that protonation has occurred at all four amine N atoms. The asymmetric unit contains one half-cation (completed by crystallographic inversion symmetry), two chloride anions and two water mol-ecules. There are two mol-ecules in the unit cell. The Cl- anions and hydrate mol-ecules are involved in hydrogen bonding. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the macrocycle N-H groups and water O-H groups as donors and the O atoms of the water mol-ecules and the Cl- anions as acceptors, giving rise to a three-dimensional network.

14.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 3): 278-281, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29765706

RESUMEN

The asymmetric unit of the title compound, Ag[Cr(C11H14N2O8)]·3H2O, contains one [Cr(1,3-pdta)]- anion [1,3-pdta is (propane-1,3-diyldi-nitrilo)-tetra-acetate], one Ag+ cation and three water mol-ecules. The Cr3+ ion is coordinated to the four O and two N atoms of the 1,3-pdta ligand, displaying a distorted octa-hedral geometry. The mean Cr-N and Cr-O bond lengths are 2.0727 (17) and 1.9608 (15) Å, respectively. The conformations of the chelate rings were found to be envelope for the glycinates and twist-boat for the six-membered di-amine (T) ring. The Ag+ cation is surrounded by six O atoms from three non-coordinated carbonyl O atoms of neighbouring 1,3-pdta groups and three water mol-ecules. The crystal structure is stabilized by inter-molecular hydrogen bonding involving the water O-H group as donor and the carboxyl O atom as acceptor.

15.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 4): 461-464, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29765746

RESUMEN

The asymmetric unit of the title compound, [Ag(C24H46N6O2)](NO3)2 [C24H46N6O2 is (5,16-dimethyl-2,6,13,17-tetra-aza-tri-cyclo-[16.4.0.07,12]docosane-2,13-di-yl)diacetamide, L], consists of one independent half of the [Ag(C24H46N6O2)]2+ cation and one nitrate anion. The Ag atom, lying on an inversion centre, has a square-planar geometry and the complex adopts a stable trans-III conformation. Inter-estingly, the two O atoms of the pendant acetamide groups are not coordinated to the AgII ion. The longer distance of 2.227 (2) Šfor Ag-N(tertiary) compared to 2.134 (2) Šfor Ag-N(secondary) may be due to the effects of the attached acetamide group on the tertiary N atom. Two nitrate anions are very weakly bound to the AgII ion in the axial sites and are further connected to the ligand of the cation by N-H⋯O hydrogen bonds. The crystal packing is stabilized by hydrogen-bonding inter-actions among the N-H donor groups of the macrocycle and its actetamide substituents, and the O atoms of the nitrate anions and of an acetamide group as the acceptor atoms.

16.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 5): 755-758, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28529791

RESUMEN

The asymmetric unit of the hydrated title salt, (C10H28N4)[Cr2O7]2·H2O [C10H28N4 = H4(cyclam) = 1,4,8,11-tetra-azonia-cyclo-tetra-deca-ne], contains two half-cations (both completed by crystallographic inversion symmetry), two dichromate anions and one water mol-ecule. The two [CrO7]2- anions exhibit a nearly staggered conformation, with bridging angles of 133.37 (11) and 136.28 (12)°. The distortions of the dichromate anions are due to their participation in hydrogen-bonding inter-actions with the water mol-ecule and the cations. Inter-molecular hydrogen bonds involving the cyclam N-H groups and water O-H groups as donor groups, and the O atoms of the dichromate anions as acceptor groups give rise to a three-dimensional network.

17.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 3): 387-389, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28316816

RESUMEN

The structure of the title compound, C21H40N4·2H2O, has been determined from synchrotron X-ray radiation data. The asymmetric unit comprises one 12-membered macropolycycle and two lattice water mol-ecules. The macropolycycle contains two cyclo-hexane rings and one 1,3-di-aza-cyclo-hexane ring, all in chair conformations. The C-N and C-C bond lengths are in the ranges 1.4526 (16)-1.4786 (17) and 1.517 (2)-1.5414 (17) Å, respectively. One intra-molecular N-H⋯N hydrogen bond helps to stabilize the mol-ecular conformation while medium-strength inter-molecular N-H⋯O, O-H⋯N and O-H⋯O hydrogen bonds involving the lattice water mol-ecules connect the components into a three-dimensional network.

18.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 3): 403-406, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28316819

RESUMEN

The asymmetric unit of the title compound, [Cr(C2O4)(C10H24N4)]2[Cr2O7]·8H2O (C10H24N4 = 1,4,8,11-tetra-aza-cyclo-tetra-decane, cyclam; C2O4 = oxalate, ox) contains one [Cr(ox)(cyclam)]+ cation, one half of a dichromate anion that lies about an inversion centre so that the bridging O atom is equally disordered over two positions, and four water mol-ecules. The terminal O atoms of the dichromate anion are also disordered over two positions with a refined occupancy ratio 0.586 (6):0.414 (6). The CrIII ion is coordinated by the four N atoms of the cyclam ligand and one bidentate oxalato ligand in a cis arrangement, resulting in a distorted octa-hedral geometry. The Cr-N(cyclam) bond lengths are in the range 2.069 (2)-2.086 (2) Å, while the average Cr-O(ox) bond length is 1.936 Å. The macrocyclic cyclam moiety adopts the cis-V conformation. The dichromate anion has a staggered conformation. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the cyclam N-H groups and water O-H groups as donors, and the O atoms of oxalate ligand, water mol-ecules and the Cr2O72- anion as acceptors, giving rise to a three-dimensional network.

19.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 1): 72-75, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-28083140

RESUMEN

The structure of the complex salt, cis-[Cr(NCS)2(cyclam)]2[Cr2O7]·H2O (cyclam = 1,4,8,11-tetra-aza-cyclo-tetra-decane, C10H24N4), has been determined from synchrotron data. The asymmetric unit comprises of one [Cr(NCS)2(cyclam)]+ cation, one half of a Cr2O72- anion (completed by inversion symmetry) and one half of a water mol-ecule (completed by twofold rotation symmetry). The CrIII ion is coordinated by the four cyclam N atoms and by two N atoms of cis-arranged thio-cyanate anions, displaying a distorted octa-hedral coordination sphere. The Cr-N(cyclam) bond lengths are in the range 2.080 (2) to 2.097 (2) Šwhile the average Cr-N(NCS) bond length is 1.985 (4) Å. The macrocyclic cyclam moiety adopts the cis-V conformation. The bridging O atom of the dichromate anion is disordered around an inversion centre, leading to a bending of the Cr-O-Cr bridging angle [157.7 (3)°]; the anion has a staggered conformation. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the cyclam N-H groups and water O-H groups as donor groups, and the O atoms of the Cr2O72- anion and water mol-ecules as acceptor groups, giving rise to a three-dimensional network.

20.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 12): 1872-1874, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27980853

RESUMEN

The structure of the title hybrid compound, (C6H16N2)[CrO4], has been determined from synchrotron data. The organic cation adopts a chair conformation. The inorganic CrO42- anion is slightly distorted owing to its involvement in N-H⋯O hydrogen-bonding inter-actions with neighbouring trans-cyclo-hexane-1,2-di-ammonium cations, whereby the two Cr-O bonds to the O atoms acting as acceptor atoms for two hydrogen bonds are slightly longer than the other two Cr-O bonds for which only one acceptor inter-action per O atom is observed. In the crystal, cations and anions are packed into layers parallel to (001), held together through the aforementioned N-H⋯O hydrogen bonds.

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