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1.
Phys Chem Chem Phys ; 26(9): 7269-7275, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38193864

RESUMO

On the basis of variable-temperature single-crystal X-ray diffraction, rotational energy barrier analysis, variable-temperature/frequency dielectric response, and molecular dynamics simulations, here we report a new crystalline supramolecular rotor (CH3NH3)(18-crown-6)[CuCl3], in which the (H3C-NH3)+ ion functions as a smallest dual-wheel rotator showing bisected rotation dynamics, while the host 18-crown-6 macrocycle behaves as a stator that is not strictly stationary. This study also provides a helpful insight into the dynamics of ubiquitous -CH3/-NH3 groups confined in organic or organic-inorganic hybrid solids.

2.
Lancet ; 400(10346): 116-125, 2022 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-35810757

RESUMO

BACKGROUND: The benefit of combined treatment with intravenous thrombolysis before endovascular thrombectomy in patients with acute ischaemic stroke caused by large vessel occlusion remains unclear. We hypothesised that the clinical outcomes of patients with stroke with large vessel occlusion treated with direct endovascular thrombectomy within 4·5 h would be non-inferior compared with the outcomes of those treated with standard bridging therapy (intravenous thrombolysis before endovascular thrombectomy). METHODS: DIRECT-SAFE was an international, multicentre, prospective, randomised, open-label, blinded-endpoint trial. Adult patients with stroke and large vessel occlusion in the intracranial internal carotid artery, middle cerebral artery (M1 or M2), or basilar artery, confirmed by non-contrast CT and vascular imaging, and who presented within 4·5 h of stroke onset were recruited from 25 acute-care hospitals in Australia, New Zealand, China, and Vietnam. Eligible patients were randomly assigned (1:1) via a web-based, computer-generated randomisation procedure stratified by site of baseline arterial occlusion and by geographic region to direct endovascular thrombectomy or bridging therapy. Patients assigned to bridging therapy received intravenous thrombolytic (alteplase or tenecteplase) as per standard care at each site; endovascular thrombectomy was also per standard of care, using the Trevo device (Stryker Neurovascular, Fremont, CA, USA) as first-line intervention. Personnel assessing outcomes were masked to group allocation; patients and treating physicians were not. The primary efficacy endpoint was functional independence defined as modified Rankin Scale score 0-2 or return to baseline at 90 days, with a non-inferiority margin of -0·1, analysed by intention to treat (including all randomly assigned and consenting patients) and per protocol. The intention-to-treat population was included in the safety analyses. The trial is registered with ClinicalTrials.gov, NCT03494920, and is closed to new participants. FINDINGS: Between June 2, 2018, and July 8, 2021, 295 patients were randomly assigned to direct endovascular thrombectomy (n=148) or bridging therapy (n=147). Functional independence occurred in 80 (55%) of 146 patients in the direct thrombectomy group and 89 (61%) of 147 patients in the bridging therapy group (intention-to-treat risk difference -0·051, two-sided 95% CI -0·160 to 0·059; per-protocol risk difference -0·062, two-sided 95% CI -0·173 to 0·049). Safety outcomes were similar between groups, with symptomatic intracerebral haemorrhage occurring in two (1%) of 146 patients in the direct group and one (1%) of 147 patients in the bridging group (adjusted odds ratio 1·70, 95% CI 0·22-13·04) and death in 22 (15%) of 146 patients in the direct group and 24 (16%) of 147 patients in the bridging group (adjusted odds ratio 0·92, 95% CI 0·46-1·84). INTERPRETATION: We did not show non-inferiority of direct endovascular thrombectomy compared with bridging therapy. The additional information from our study should inform guidelines to recommend bridging therapy as standard treatment. FUNDING: Australian National Health and Medical Research Council and Stryker USA.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , Acidente Vascular Cerebral , Adulto , Austrália , Isquemia Encefálica/tratamento farmacológico , Procedimentos Endovasculares/métodos , Fibrinolíticos/efeitos adversos , Humanos , Estudos Prospectivos , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Resultado do Tratamento
3.
Chemistry ; 29(38): e202300598, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37062699

RESUMO

Multifunctional materials with working temperatures near room temperature are crucial for practical applications. Until now, it is still a great challenge to obtain such materials. In this paper, a complex of (C5 NH13 Cl)2 MnBr4 (1) with a structural phase transition near room temperature is reported. The phase transition induces switchable magnetic properties, dielectric anomalies and luminescent response over the same range of temperatures. It is the first time the synergetic effect of magnetism, dielectricity and luminescence near room temperature have been observed in the same molecular complex.


Assuntos
Luminescência , Magnetismo , Temperatura , Transição de Fase
4.
Int J Clin Pract ; 2023: 2857115, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37292385

RESUMO

Objectives: The purpose of this cross-sectional study was to examine the relationship between perfectionism and pain in patients with temporomandibular disorders (TMDs). Methods: A total of 345 TMD patients were included. A questionnaire consisting of questions of demographic information, the 15-item short form of the Hewitt and Flett Multidimensional Perfectionism Scale, and the Patient Health Questionnaire-4 (PHQ-4) was distributed. According to the diagnostic criteria for TMDs, patients were categorized as pain-related (PT) and non-pain-related (NPT) groups, whereas PT patients were further divided into patients with pain-related TMDs only (OPT) and patients with combined pain-related and intra-articular TMDs (CPT). Data were analyzed using the chi-square test, Spearman's correlation, and logistic regression analysis with the significance level set at p < 0.05. Results: There were 68 patients in the NPT group, 80 in the OPT group, and 197 in the CPT group. PT patients had significantly higher perfectionism scores (63.58 ± 13.63) than NPT patients (56.32 ± 12.95, p < 0.001). The PHQ-4 score in the PT group was also higher. After adjusting the PHQ-4 scores, perfectionism scores of the PT group were 6.11 points higher than those in the NPT group (p < 0.001). There were no statistical differences in all parameters of OPT and CPT groups (p > 0.05). Perfectionism in total, other-oriented perfectionism (OOP), and socially prescribed perfectionism (SPP) showed significant but weak correlations with PHQ-4 scores (p < 0.001), while self-oriented perfectionism (SOP) was also significantly but very weakly correlated with PHQ-4 scores (p < 0.05). Conclusions: Pain-related TMD patients exhibited higher perfectionism scores than NPT patients, and neither their perfectionism nor pain scores were correlated with intra-articular diseases of TMJ. OOP and SOP presented weak correlations with psychological distress in TMD patients. It is suggested that pain-related TMD patients could be screened for perfectionism and perfectionism could be considered when proposing psychological treatment strategies to PT patients.


Assuntos
Perfeccionismo , Transtornos da Articulação Temporomandibular , Humanos , Estudos Transversais , Transtornos da Articulação Temporomandibular/complicações , Dor , Inquéritos e Questionários
5.
Molecules ; 28(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38005227

RESUMO

Multifunctional materials with a coexistence of proton conduction properties, single-molecule magnet (SMM) behaviors and magneto-optical Faraday effects have rarely been reported. Herein, a new pair of Cu(II)-Dy(III) enantiomers, [DyCu2(RR/SS-H2L)2(H2O)4(NO3)2]·(NO3)·(H2O) (R-1 and S-1) (H4L = [RR/SS] -N,N'-bis [3-hydroxysalicylidene] -1,2-cyclohexanediamine), has been designed and prepared using homochiral Schiff-base ligands. R-1 and S-1 contain linear Cu(II)-Dy(III)-Cu(II) trinuclear units and possess 1D stacking channels within their supramolecular networks. R-1 and S-1 display chiral optical activity and strong magneto-optical Faraday effects. Moreover, R-1 shows a zero-field SMM behavior. In addition, R-1 demonstrates humidity- and temperature-dependent proton conductivity with optimal values of 1.34 × 10-4 S·cm-1 under 50 °C and 98% relative humidity (RH), which is related to a 1D extended H-bonded chain constructed by water molecules, nitrate and phenol groups of the RR-H2L ligand.

6.
Angew Chem Int Ed Engl ; 57(27): 8032-8036, 2018 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-29722925

RESUMO

Dielectric switches that can be converted between high and low dielectric states by thermal stimuli have attracted much interest owing to their many potential applications. Currently one main drawback for practical application lies in the non-tunability of their switch temperatures (TS ). We report here an ionic co-crystal (Me3 NH)4 [Ni(NCS)6 ] that contains a multiply rotatable Me3 NH+ ion and a solely rotatable one due to a more spacious supramolecular cage for the former one. This compound undergoes an isostructural order-disorder phase transition and it can function as a frequency-tuned dielectric switch with highly adjustable TS , which is further revealed by the variable-temperature structure analyses and molecular dynamics simulations. In addition, the distinct arrangements and molecular dynamics of two coexisting Me3 NH+ ions confined in different lattice spaces as well as the notable offset effect on the promoting/hindering of dipolar reorientation after dielectric transition provide a rarely observed but fairly good model for understanding and modulating the dipole motion in crystalline environment.

7.
Inorg Chem ; 55(21): 11418-11425, 2016 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-27767313

RESUMO

Plastic crystals functioning with rotatable components offer new opportunities in areas such as modern optoelectronic materials. Here, by taking advantage of controllable rotation of the polar component within the ion-pair plastic-crystal system, we present two such crystals, namely, (Et4N)(CrO3X) (X = Cl or Br), which are unusual examples exhibiting two-staged thermosensitive dielectric responses above room temperature. The frequency-dependent response in the first stage is due to the structural phase transitions, whereas that in the second stage is induced by dynamic rotation of the polar halochromate anions in their NaCl-type plastic-crystal phases. The intrinsic mechanisms were also explicated by molecular dynamics simulations, providing a direct insight into the dynamic characteristics of these two compounds. These studies show that ionic plastic crystals functioning with polar groups are an attractive candidate as sensitive thermoresponsive dielectric materials.

8.
J Phys Chem Lett ; 14(36): 8009-8015, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37651131

RESUMO

Free accessible confined space and loose interaction are crucial for most solid-state ionic motions. Here, by using a near-spherical anion and a disc-shaped ammonium as two distinct but rigid building blocks, we report a new ionic crystal, (HMIm)3[La(NO3)6] (HMIm = 1-methyl-1H-imidazol-3-ium), in which the different confined spaces of three (HMIm)+ ions are fine-tuned over a broad temperature range. This effect can be utilized to modulate the dipolar polarization across a wide temperature/frequency range. Additionally, small-scale substitution of (HMIm)+ by its isomer of almost identical shape/size affords molecular solid solutions, which can further tune the dipolar polarization by varying the doping ratio. It is revealed that the differences in dipole moment and hydrogen bond rather than that of shape/size lead to a distorted crystalline environment for these solid solutions. Overall, we provide an exceptional model for understanding and regulating the dipole motion of polar aromatic molecules/ions in a crystalline environment.

9.
J Integr Plant Biol ; 54(12): 991-1006, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23013333

RESUMO

The link between root growth, H2O2, auxin signaling, and the cell cycle in cadmium (Cd)-stressed rice (Oryza sativa L. cv. Zhonghua No. 11) was analyzed in this study. Exposure to Cd induced a significant accumulation of Cd, but caused a decrease in zinc (Zn) content which resulted from the decreased expression of OsHMA9 and OsZIP. Analysis using a Cd-specific probe showed that Cd was mainly localized in the meristematic zone and vascular tissues. Formation and elongation of the root system were significantly promoted by 3-amino-1,2,4-triazole (AT), but were markedly inhibited by N,N'-dimethylthiourea (DMTU) under Cd stress. The effect of H2O2 on Cd-stressed root growth was further confirmed by examining a gain-of-function rice mutant (carrying catalase1 and glutathione-S-transferase) in the presence or absence of diphenylene iodonium. DR5-GUS staining revealed close associations between H2O2 and the concentration and distribution of auxin. H2O2 affected the expression of key genes, including OsYUCCA, OsPIN, OsARF, and OsIAA, in the auxin signaling pathway in Cd-treated plants. These results suggest that H2O2 functions upstream of the auxin signaling pathway. Furthermore, H2O2 modified the expression of cell-cycle genes in Cd-treated roots. The effects of H2O2 on root system growth are therefore linked to auxin signal modification and to variations in the expression of cell-cycle genes in Cd-stressed rice. A working model for the effects of H2O2 on Cd-stressed root system growth is thus proposed and discussed in this paper.


Assuntos
Cádmio/toxicidade , Genes cdc , Peróxido de Hidrogênio/farmacologia , Ácidos Indolacéticos/metabolismo , Oryza/genética , Raízes de Plantas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Oryza/citologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo
10.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 1): m38-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22259339

RESUMO

In the title polymer, {[Cu(C(8)H(12)N(2)O(6)P(2))]·2H(2)O}(n), the geometry of the five-coordinate Cu(II) ion can best be described as slightly distorted square-pyramidal formed by one N and two O atoms of an N(CH(2)PO(3)H)(2) group and one N atom from a pyridine ring. The elongated apex of the pyramid is occupied by one O atom from a third diphospho-nate ligand. The inter-connection of Cu(2+) ions by the diphospho-nate ligands results in the formation of a double-chain array along the b axis, in which the two sub-chains are inter-locked by pairs of PO(3) groups. The outside of each sub-chain is decorated by other PO(3) groups. These double chains are further assembled into a three-dimensional supra-molecular architecture via a large number of O-H⋯O hydrogen bonds between the phospho-nate groups and lattice water mol-ecules.

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