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1.
Mult Scler Relat Disord ; 60: 103745, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35306241

RESUMO

BACKGROUND: Higher levels of moderate to vigorous physical activity (MVPA) associate with disease activity in pediatric multiple sclerosis (MS). Further, measures of retinal integrity associate with lower brain atrophy, yet the relationship of retinal integrity with MVPA has not been investigated. OBJECTIVE: To determine the relationship between MVPA and retinal nerve fibre layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) thickness in patients with MS, myelin oligodendrocyte glycoprotein-associated disorders (MOGAD), neuromyelitis optica spectrum disorder (NMOSD), and monophasic acquired demyelinating syndromes (monoADS). METHODS: 150 consecutive children ≤18 y.o with neuroinflammatory disorders were included. Outcomes included the Godin Leisure Time Activity Questionnaire (GLTEQ) modeled as both a continuous and categorical variable (any vs no MVPA/Strenuous activity), and RNFL and GCIPL using linear mixed models (JASP 0.14.1). RESULTS: An association was identified between MVPA with RNFL thickness (F (1,133) = 8.40, p = .004) and GCIPL thickness (F(1, 131) = 7.68, p = .006). In the MS cohort, any strenuous physical activity was associated with greater RNFL (F(1,35) = 7.30, p = .011) and GCIPL thickness (F(1,35) = 8.73, p =.006). CONCLUSIONS: Any MVPA participation is associated with higher RNFL and GCIPL thickness across neuroinflammatory disorders.


Assuntos
Esclerose Múltipla , Células Ganglionares da Retina , Adolescente , Benchmarking , Criança , Exercício Físico , Humanos , Doenças Neuroinflamatórias , Tomografia de Coerência Óptica
2.
Dalton Trans ; 40(34): 8685-94, 2011 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-21792429

RESUMO

The di-hydride di-anion [H(2)Fe(4)(CO)(12)](2-) has been quantitatively obtained by protonation of the previously reported mono-hydride tri-anion [HFe(4)(CO)(12)](3-) in DMSO and structurally characterised in its [NEt(4)](2)[H(2)Fe(4)(CO)(12)] salt. It shows some subtle but yet significant differences in the stereochemistry of the ligands in comparison to the heavier Ru(4) and Os(4) congeners. The study of the reactivity of these [H(4 -n)Fe(4)(CO)(12)](n-) (n = 2,3) species allowed the serendipitous isolation and structural characterization of the new pentanuclear [HFe(5)(CO)(14)](3-) mono-hydride tri-anion. Attempts to obtain the latter in better yields led to the discovery of intermolecular CO/H(-) mutual exchange reactions and isolation and structural characterization of the [Fe(DMF)(4)][Fe(4)(CO)(12)(µ(5)-η(2)-CO)(µ-H)](2)·0.5CH(2)Cl(2) and [M(+)][Fe(4)(CO)(12)(µ(4)-η(2)-CO)(µ-H)](-) (M = K, Cs) adducts, the former containing an unprecedented isocarbonyl group. The isolation of new tetranuclear and, above all, pentanuclear hydridocarbonylferrates indicates that it is possible to further expand the chemistry of homoleptic Fe carbonyl species.

3.
Dalton Trans ; 40(18): 5002-8, 2011 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-21416073

RESUMO

The inter-conversions of platinum carbonyl dianionic clusters, ([Pt(3)(CO)(6)](n)(2-), n = 2-5), have been studied in THF and acetonitrile using in situ FTIR spectroscopy. These inter-conversions were facilitated by the addition (or removal) of molecular hydrogen. The individual reactions, namely reductions and oxidations of [Pt(3)(CO)(6)](n)(2-) were fast and reversible. BTEM analysis of the data provided the pure component spectra of the individual species without the need for physical separation. It is shown, for the first time, that the species [Pt(3)(CO)(6)](n)(2-) (n = 2) can be formed from the reduction of [Pt(3)(CO)(6)](n)(2-) (n = 3-5) by hydrogen alone in acetonitrile. Also, detection of dissolved CO(2) in solution suggests that a room-temperature water gas shift reaction occurs. This has been shown to arise from nucleophilic attack of water on a coordinated CO of [Pt(3)(CO)(6)](n)(2-) which leads to the formation of [HPt(15)(CO)(19)](3-) and [H(2)Pt(15)(CO)(19)](2-). The parent tetraanion, [Pt(15)(CO)(19)](4-), has been isolated in high yields by reaction of [Pt(3)(CO)(6)](n)(2-) (n = 2, 3) with NaOH at 60 °C and has been structurally characterized by X-ray analysis.

4.
Inorg Chem ; 42(20): 6314-22, 2003 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-14514307

RESUMO

The nu(CO) vibrational spectra of planar transition cluster carbonyls containing M(CO)(4) groups are studied. It is possible to anticipate qualitatively, both for the infrared and Raman, the band intensity changes associated with increasing metallic nature of the cluster. These enable a unification of the band patterns shown by the species reported. As for (idealized) spherical clusters, the spherical harmonic model (SHM), suitably modified, becomes of more general applicability as cluster size increases, although for smaller species the tensor harmonic model (THM) makes a contribution.

5.
Chem Commun (Camb) ; (18): 1776-7, 2001 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-12240310

RESUMO

The reaction of [NnBu4]2[Ni6(CO)12] in THF solution with 1.5-2 equivalents of K2PtCl4 leads to formation of the [Ni24Pt14(CO)44]4- and [Ni10(Ni6-xPtx)Pt8(CO)30]4- (x approximately 2) tetraanions, the latter presents a localised substitutional Ni/Pt disorder and an unprecedented close-packed metal structure.

6.
Angew Chem Int Ed Engl ; 39(9): 1635-1637, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10820459
7.
Angew Chem Int Ed Engl ; 38(24): 3724-3727, 1999 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-10649338

RESUMO

The intermediacy of CO/NO substitution in the condensation of [Pt(19)(CO)(22)](4-) into [Pt(38)(CO)(44)](2-) (structure shown) has been demonstrated. Two high-nuclearity carbonyl metal clusters, including one with an unprecedented nitrosyl ligand, have been synthesized and structurally characterized.

8.
Inorg Chem ; 37(17): 4335-4343, 1998 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-11670570

RESUMO

Results from liquid X-ray scattering show that both [Ni(6)(CO)(12)](2)(-) and [Pt(6)(CO)(12)](2)(-) adopt an overall staggered ditriangular structure of D(3) symmetry in solution. Theoretical calculations show that the energy barrier of rotation is quite small, in particular for the platinum cluster. The possibilities to stabilize monotriangular carbonyl clusters of Ni and Pt in solution were also investigated. Only monotriangular [Pt(3)(CO)(6)](2)(-) can be stabilized as verified by NMR and IR spectroscopy as well as X-ray scattering. The structure is analogous to that found in the individual triangular units of [Pt(6)(CO)(12)](2)(-), and there is no unambiguous evidence for the need of additional apical CO's to stabilize [Pt(3)(CO)(6)](2)(-) in solution. Attempts to isolate the corresponding [Ni(3)(CO)(6)](2)(-) cluster instead produced the very stable [Ni(5)(CO)(12)](2)(-). Mixed solutions of the ditriangular clusters give rise to heteroclusters, whose chemistry is dominated by the facile disproportionation of the Ni(6) clusters.

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