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1.
J Am Chem Soc ; 146(26): 18104-18116, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38899355

RESUMO

The submarine-confined bubble swarm is considered an important constraining environment for the early evolution of living matter due to the abundant gas/water interfaces it provides. Similarly, the spatiotemporal characteristics of the confinement effect in this particular scenario may also impact the origin, transfer, and amplification of chirality in organisms. Here, we explore the confinement effect on the chiral hierarchical assembly of the amphiphiles in the confined bubble array stabilized by the micropillar templates. Compared with the other confinement conditions, the assembly in the bubble scenario yields a fractal morphology and exhibits a unique level of the chiral degree, ordering, and orientation consistency, which can be attributed to the characteristic interfacial effects of the rapidly formed gas/water interfaces. Thus, molecules with a balanced amphiphilicity can be more favorable for the promotion. Not limited to the pure enantiomers, chiral amplification of the enantiomer-mixed assembly is observed only in the bubble scenario. Beyond the interfacial mechanism, the fast formation kinetics of the confined liquid bridges in the bubble scenario endows the assembly with the tunable hierarchical morphology when regulating the amphiphilicity, aggregates, and confined spaces. Furthermore, the chiral-induced spin selectivity (CISS) effect of the fractal hierarchical assembly was systematically investigated, and a strategy based on photoisomerization was developed to efficiently modulate the CISS effect. This work provides insights into the robustness of confined bubble swarms in promoting a chiral hierarchical assembly and the potential applications of the resulting chiral hierarchical patterns in solid-state spintronic and optical devices.

2.
Small ; : e2401954, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733233

RESUMO

Achiral solvents are commonly utilized to induce the self-assembly of chiral molecules. This study demonstrates that achiral solvents can trigger helicity inversion in the assemblies of dansyl amphiphiles and control the excited-state "majority rule" in assemblies composed of pure enantiomers, through variation of the cosolvent ratio. Specifically, enantiomers of dansyl amphiphiles self-assemble into helical structures with opposite handedness in methanol (MeOH) and acetonitrile (MeCN), together with inversed circular dichroism and circularly polarized luminescence (CPL) signals. When a mixture of MeOH and MeCN is employed, the achiral cosolvents collectively affect the CPL of the assemblies in a way similar to that of "mixed enantiomers". The dominant cosolvent governs the CPL signal. As the cosolvent composition shifts from pure MeCN to MeOH, the CPL signals undergo a significant inversion and amplification, with two maxima observed at ≈20% MeOH and 20% MeCN. This study deepens the comprehension of how achiral solvents modulate helical nanostructures and their excited-state chiroptical properties.

3.
Small ; 20(10): e2306400, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37880901

RESUMO

Chirality-directed stem-cell-fate determination involves coordinated transcriptional and metabolomics programming that is only partially understood. Here, using high-throughput transcriptional-metabolic profiling and pipeline network analysis, the molecular architecture of chirality-guided mesenchymal stem cell lineage diversification is revealed. A total of 4769 genes and 250 metabolites are identified that are significantly biased by the biomimetic chiral extracellular microenvironment (ECM). Chirality-dependent energetic metabolism analysis has revealed that glycolysis is preferred during left-handed ECM-facilitated osteogenic differentiation, whereas oxidative phosphorylation is favored during right-handed ECM-promoted adipogenic differentiation. Stereo-specificity in the global metabolite landscape is also demonstrated, in which amino acids are enriched in left-handed ECM, while ether lipids and nucleotides are enriched in right-handed ECM. Furthermore, chirality-ordered transcriptomic-metabolic regulatory networks are established, which address the role of positive feedback loops between key genes and central metabolites in driving lineage diversification. The highly integrated genotype-phenotype picture of stereochemical selectivity would provide the fundamental principle of regenerative material design.


Assuntos
Multiômica , Osteogênese , Linhagem da Célula/genética , Diferenciação Celular/genética , Metabolômica
4.
Arterioscler Thromb Vasc Biol ; 43(3): 474-481, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36727517

RESUMO

BACKGROUND: Brain arterial dilation and elongation characterize dolichoectasia, an arteriopathy associated with risk of stroke and death. We aim to determine whether brain arterial elongation increases the risk of stroke and death independent of brain arterial diameters. METHODS: We analyzed 1210 stroke-free participants (mean age 71±9 years, 41% men, 65% Hispanic) with available time-of-flight magnetic resonance angiogram from the Northern Manhattan Study, a population-based cohort study across a multiethnic urban community. We obtained baseline middle cerebral artery M1-segment (MCA-M1) and basilar artery (BA) mean lengths and diameters using a semi-automated software. Cox proportional hazards models adjusted for brain arterial diameters and potential confounders yielded adjusted hazards ratios with 95% CIs for the primary outcomes of incident stroke and all-cause mortality, as well as secondary outcomes including noncardioembolic stroke, vascular death, and any vascular event. RESULTS: Neither MCA-M1 nor BA lengths correlated with incident stroke or all-cause mortality. Both MCA-M1 and BA larger diameters correlated with all-cause mortality (MCA-M1 aHR, 1.52 [95% CI, 1.03-2.23], BA aHR, 1.28 [95% CI, 1.02-1.61]), as well as larger MCA-M1 diameters with vascular death (aHR, 1.84 [95% CI, 1.02-3.31]). Larger MCA-M1 and BA diameters did not correlate with incident stroke. However, larger BA diameters were associated with posterior circulation noncardioembolic stroke (aHR, 2.93 [95% CI, 1.07-8.04]). There were no statistical interactions between brain arterial lengths and diameters in relation to study outcomes. CONCLUSIONS: In a multiethnic cohort of stroke-free adults, brain arterial elongation did not correlate with risk of stroke or death, nor influenced the significant association between brain arterial dilation and vascular risk.


Assuntos
Noma , Acidente Vascular Cerebral , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Estudos de Coortes , Encéfalo , Artéria Cerebral Média , Fatores de Risco
5.
Alzheimers Dement ; 20(4): 2497-2507, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38332543

RESUMO

INTRODUCTION: We tested the association of brain artery diameters with dementia and stroke risk in three distinct population-based studies using conventional T2-weighted brain magnetic resonance imaging (MRI) images. METHODS: We included 8420 adults > 40 years old from three longitudinal population-based studies with brain MRI scans. We estimated and meta-analyzed the hazard ratios (HRs) of the brain and carotids and basilar diameters associated with dementia and stroke. RESULT: Overall and carotid artery diameters > 95th percentile increased the risk for dementia by 1.74 (95% confidence interval [CI], 1.13-2.68) and 1.48 (95% CI, 1.12-1.96) fold, respectively. For stroke, meta-analyses yielded HRs of 1.59 (95% CI, 1.04-2.42) for overall arteries and 2.11 (95% CI, 1.45-3.08) for basilar artery diameters > 95th percentile. DISCUSSION: Individuals with dilated brain arteries are at higher risk for dementia and stroke, across distinct populations. Our findings underline the potential value of T2-weighted brain MRI-based brain diameter assessment in estimating the risk of dementia and stroke.


Assuntos
Demência , Acidente Vascular Cerebral , Adulto , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/complicações , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Artéria Basilar , Demência/diagnóstico por imagem , Demência/epidemiologia , Demência/complicações , Fatores de Risco
6.
Angew Chem Int Ed Engl ; 63(6): e202316863, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38116831

RESUMO

Pathway-dependent self-assembly, in which a single building block forms two or more types of self-assembled nanostructures, is an important topic due to its mimic to the complexity in biology and manipulation of diverse supramolecular materials. Here, we report a pathway-dependent self-assembly using chiral glutamide derivatives (L or D-PAG), which form chiral nanotwist and nanotube through a cooperative slow cooling and an isodesmic fast cooling process, respectively. Furthermore, pathway-dependent self-assembly can be harnessed to control over the supramolecular co-assembly of PAG with a luminophore ß-DCS or a photopolymerizable PCDA. Fast cooling leads to the co-assembled PAG/ß-DCS nanotube exhibiting green circularly polarized luminescence (CPL), while slow cooling to nanofiber with blue CPL. Additionally, fast cooling process promotes the photopolymerization of PCDA into a red chiral polymer, whereas slow cooling inhibits the polymerization. This work not only demonstrates the pathway-dependent control over structural characteristics but also highlights the diverse functions emerged from the different assemblies.

7.
Angew Chem Int Ed Engl ; : e202411733, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39115949

RESUMO

Here we designed enantiomeric lipid-mimetic glutamic acid derivatives (L/D-UG) and investigated their self-assembled chiral nanostructures and performance with the protein adsorption as well as the osteogenesis. It was found that L or D-UG can self-assemble into vesicle bilayers and two-dimensional (2D) nanocrystals via a kinetic and thermodynamic control, respectively. These chiral vesicles and 2D crystals showed differentiated adsorption of proteins by their curvature and chirality. Specifically, fibronectin constituted by L-amino acids adsorbed preferentially on L-UG 2D crystal in a semi-random pattern and L-2D nanocrystal show as the most effective structures to promote bone regeneration. The controlled vesicle and 2D crystal assemblies with different chirality and curvature helps to clarify their determine roles in protein adsorption and osteogenesis.

8.
Angew Chem Int Ed Engl ; 63(35): e202408056, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-38758007

RESUMO

Here, we successfully synthesized four structurally analogous, self-assembled chiral molecular tubes with relatively high yields. This achievement involved the condensation of six equivalents of enantiomerically pure trans-cyclohexane-1,2-diamine (trans-CHDA) and three equivalents of the corresponding tetraformyl precursor. Each precursor was equipped with a luminescent linker terminated by two m-phthalaldehyde units. Even though these tetraformyl precursors are barely soluble in almost all organic solvents, the molecular tubes are highly soluble in nonpolar solvents such as chloroform, allowing us to fully characterize them in solution. The stereo-chirality of the chiral bisamino building blocks endows the frameworks of molecular tubes with planar chirality. As a consequence, all of these molecular tubes exhibit circularly polarized luminescence (CPL) with relatively large dissymmetry values |glum| up to 7×10-3, providing an efficient method for synthesizing CPL-active materials.

9.
Stroke ; 54(1): 159-166, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36416126

RESUMO

BACKGROUND: Although protective in secondary stroke prevention of intracranial arterial stenosis (ICAS), it is uncertain if the benefits of leisure time physical activity (LTPA) extend to asymptomatic ICAS or extracranial carotid stenosis (ECAS). Therefore, we sought to determine LTPA's relationship with ECAS and ICAS in a stroke-free, race-ethnically diverse cohort. METHODS: This cross-sectional study included participants from the magnetic resonance imaging substudy of the Northern Manhattan Study, of whom 1274 had LTPA assessments at enrollment. LTPA was represented continuously as metabolic equivalent score (MET-score) and ordinally as model-based cluster analysis (LTPA-cluster), both based on the same LTPA assessments. We evaluated ECAS sonographically using carotid intima-media thickening and number of carotid plaques. ICAS was assessed with time-of-flight magnetic resonance angiograph and defined as ≥50% or ≥70% stenosis. We applied regression analyses to evaluate the association between LTPA with ECAS and ICAS, adjusting for confounders. RESULTS: Of 1274 included participants (mean age 71±9 years; 60% women; 65% Hispanic), the mean MET-score was 10±16 and 60% were in a LTPA-cluster with any activity. Among those with carotid ultrasound (n=1234), the mean carotid intima-media thickening was 0.97±0.09 mm, and 56% of participants had at least one carotid plaque identified. Among those with magnetic resonance angiograph (n=1211), 8% had ≥50% ICAS and 5% had ≥70% ICAS. For ICAS, MET-score was associated with ≥70% ICAS (adjusted odds ratio per unit increase in MET-score [95% CI, 0.97 [0.94-0.99]) but not with ECAS measures (carotid intima-media thickening, adjusted ß-estimate per unit increase in MET-score [95% CI], 0.002 [-0.003 to 0.006] or number of plaques, adjusted ß-estimate [95% CI], 0.0001 [-0.0001 to 0.0003]). Substituting MET-score with LTPA-clusters replicated the association between ≥70% ICAS and LTPA (adjusted odds ratio per each increased LTPA-cluster [95% CI], 0.83 [0.70-0.99]). CONCLUSIONS: In this diverse stroke-free population, we found LTPA most strongly associated with asymptomatic ≥70% ICAS. Given the high-risk nature of ≥70% ICAS, these findings may emphasize the role of LTPA in people at risk for ICAS.


Assuntos
Estenose das Carótidas , Noma , Acidente Vascular Cerebral , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Constrição Patológica , Estudos Transversais , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/epidemiologia , Exercício Físico
10.
Stroke ; 54(12): 3030-3037, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37909207

RESUMO

BACKGROUND: Inflammation contributes to atherosclerosis but is incompletely characterized in intracranial large artery stenosis (ICAS). We hypothesized that immune markers would be associated with ICAS and modify the risk ICAS confers on future vascular events. METHODS: This study included a subsample of stroke-free participants in the prospective NOMAS (Northern Manhattan Study), who had blood samples analyzed with a 60-plex immunoassay (collected from 1993 to 2001) and ICAS assessment with time-of-flight magnetic resonance angiography (obtained from 2003 to 2008). We dichotomized ICAS as either ≥50% stenosis or not (including no ICAS). We ascertained post-magnetic resonance imaging vascular events. We used least absolute shrinkage and selection operator procedures to select immune markers independently associated with ICAS. Then, we grouped selected immune markers into a derived composite Z score. Using proportional odds regression, we quantified the association of the composite immune marker Z score, ICAS, and risk of vascular events. RESULTS: Among 1211 participants (mean age, 71±9 years; 59% women; 65% Hispanic participants), 8% had ≥50% ICAS. Using least absolute shrinkage and selection operator regression, we identified CXCL9 (C-X-C motif chemokine ligand 9), HGF (hepatocyte growth factor), resistin, SCF (stem cell factor), and VEGF-A(vascular endothelial growth factor A) to have the strongest positive relationships with ≥50% ICAS in fully adjusted models. Selected markers were used to derive a composite immune marker Z score. Over an average follow-up of 12 years, we found that each unit increase in immune marker Z scores was associated with an 8% (95% CI, 1.05-1.11), 11% (95% CI, 1.06-1.16), and 5% (95% CI, 1.01-1.09) increased hazard of death, vascular death, and any vascular event, respectively, in adjusted models. We did not find a significant interaction between immune marker Z scores and ICAS in their relationship with any longitudinal outcome. CONCLUSIONS: Among a diverse stroke-free population, selected serum immune markers were associated with ICAS and future vascular events. Further study is needed to better understand their role in the pathogenesis of ICAS and as a potential therapeutic target in stroke prevention.


Assuntos
Arteriosclerose Intracraniana , Noma , Acidente Vascular Cerebral , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Fator A de Crescimento do Endotélio Vascular , Estudos Prospectivos , Constrição Patológica/complicações , Noma/complicações , Fatores de Risco , Arteriosclerose Intracraniana/complicações , Acidente Vascular Cerebral/epidemiologia , Biomarcadores , Artérias
11.
J Am Chem Soc ; 145(50): 27639-27649, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38054305

RESUMO

While chiral molecular rotors have unique frames and cavities to possibly generate switchable chiroptical functions, it still remains a formidable challenge to precisely restrict their rotations to activate certain functions such as fluorescence as well as circularly polarized luminescence (CPL), which are strongly related to the local molecular rotations. Herein, we design a pair of enantiopure helical cage rotors, which emit light neither at the molecular state nor in the crystal or aggregation states, although they contain luminophore groups. However, upon mounting with fluoroaromatic borane (TFPB) as a molecular brake, the phenyl rotation of the helical cage can be effectively hindered and fluorescence and CPL activities of the molecular cage are switched on. Crystal structure analysis reveals that the rotation is restricted through synergistic B-O-H-N bonding and a fluoroaromatic-aromatic (ArF-Ar) dipole interaction. Moreover, the helical cages are switched on stepwise with color-variable fluorescence and CPL by the inner brake in the molecular state and the outer brake in the supramolecular assemblies, respectively. This work not only provides the design idea of chiroptical molecular rotors but also unveils how fluorescence and CPL could be generated in cage rotor systems.

12.
Funct Integr Genomics ; 23(4): 294, 2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37688632

RESUMO

In the field of biodosimetry, the current accepted method for evaluating radiation dose fails to meet the need of rapid, large-scale screening, and most RNA marker-related studies of biodosimetry are concentrating on a single type of ray, while some other potential factors, such as trauma and burns, have not been covered. Microarray datasets that contain the data of human peripheral blood samples exposed to X-ray, neutron, and γ-ray radiation were obtained from the GEO database. Totally, 33 multi-type ray co-induced genes were obtained at first from the differentially expressed genes (DEGs) and key genes identified by weighted gene co-expression network analysis (WGCNA), and these genes were mainly enriched in DNA damage, cellular apoptosis, and p53 signaling pathway. Following transcriptome sequencing of blood samples from 11 healthy volunteers, 13 patients with severe burns, and 37 patients with severe trauma, 6635 trauma-related DEGs and 7703 burn-related DEGs were obtained. Through the exclusion method, a total of 12 radiation-specific genes independent of trauma and burns were identified. ROC curve analysis revealed that the DDB2 gene performed the best in diagnosis of all three types of ray radiation, while correlation analysis showed that the MDM2 gene was the best in assessment of radiation dose. The results of multiple-linear regression analysis indicated that such analysis could improve the accuracy in assessment of radiation dose. Moreover, the DDB2 and MDM2 genes remained effective in radiation diagnosis and assessment of radiation dose in an external dataset. In general, the study brings new insights into radiation biodosimetry.


Assuntos
Queimaduras , Humanos , Queimaduras/genética , Raios gama , Apoptose , Dano ao DNA , Doses de Radiação , Proteínas de Ligação a DNA/genética , Proteínas Proto-Oncogênicas c-mdm2/genética
13.
J Transl Med ; 21(1): 345, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37221594

RESUMO

Malignant melanoma is one of the most common tumours and has the highest mortality rate of all types of skin cancers worldwide. Traditional and novel therapeutic approaches, including surgery, targeted therapy and immunotherapy, have shown good efficacy in the treatment of melanoma. At present, the mainstay of treatment for melanoma is immunotherapy combined with other treatment strategies. However, immune checkpoint inhibitors, such as PD-1 inhibitors, are not particularly effective in the clinical treatment of patients with melanoma. Changes in mitochondrial function may affect the development of melanoma and the efficacy of PD-1 inhibitors. To elucidate the role of mitochondria in the resistance of melanoma to PD-1 inhibitors, this review comprehensively summarises the role of mitochondria in the occurrence and development of melanoma, targets related to the function of mitochondria in melanoma cells and changes in mitochondrial function in different cells in melanoma resistant to PD-1 inhibitors. This review may help to develop therapeutic strategies for improving the clinical response rate of PD-1 inhibitors and prolonging the survival of patients by activating mitochondrial function in tumour and T cells.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Inibidores de Checkpoint Imunológico , Imunoterapia , Mitocôndrias
14.
Soft Matter ; 19(26): 4909-4915, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37340798

RESUMO

The self-assembly of a C3-symmetric molecule benzene-1,3,5-tricarboxylate substituted with methyl cinnamate (BTECM) has been investigated by a reprecipitation method in H2O and cetyltrimethylammonium bromide (CTAB) aqueous solution, respectively. The nanostructures and characteristics of the assemblies were monitored by UV-Vis spectroscopy, fluorescence (FL) spectroscopy, circular dichroism (CD) spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was found that helical nanostructures were successfully assembled from the achiral C3 molecule BTECM. More importantly, the helices aggregated via different packing modes in H2O and CTAB aqueous solution. In H2O, the nanostructures underwent a process of particles, fibers and helices via H-type aggregate upon aging. In the case of CTAB aqueous solution (1.2 mM), the helices were translated from particles and the molecules were inclined to aggregate via the J-type mode. In addition, the aggregation process could be accelerated by raising the temperature proved by UV-Vis spectra. A molecular aggregation mechanism was proposed based on the experimental results.

15.
Chirality ; 35(10): 692-699, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37013339

RESUMO

Because of its dynamic reversible nature and simple regulation properties, rotaxane systems provided a good route for the construction of responsive supramolecular chiral materials. Here, we covalently encapsulate the photo-responsive guest molecule azobenzene (Azo) in a chiral macrocycle ß-cyclodextrin (ß-CD) to prepare self-locked chiral [1]rotaxane [Azo-CD]. On this basis, the self-adaptive conformation of [Azo-CD] was manipulated by solvent and photoirradiation; meanwhile, dual orthogonal regulation of the [1]rotaxane chiroptical switching could also be realized.

16.
Neurol Sci ; 44(6): 2159-2166, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36710283

RESUMO

BACKGROUND: Many studies have reported reduced brain white matter fractional anisotropy (FA) and increased mean diffusivity (MD) on diffusion tensor imaging (DTI) of people with HIV (PWH). Few, however, have linked individual blood inflammatory markers with white matter tract-specific FA and MD. METHODS: PWH 50 years old or older from New York, NY, USA, were invited to a cross-sectional study. Demographic data, blood samples, and brain DTI were obtained. Least absolute shrinkage and selection operator (LASSO) regression was used to examine associations between biomarkers and white matter tract-specific FA and MD. All models included age, sex, race, ethnicity, diabetes, hypertension, smoking, and viral load as control variables. RESULTS: Seventy-two cases were analyzed. Mean age was 60 ± 6 years, 47% were women, 21% were Hispanic, and 78% were black. All had asymptomatic HIV infection and were on antiretroviral therapy. Eighty-nine percent had CD4 count >200 cell/mm3 and 78% were virally suppressed. Vascular endothelial growth factor (VEGF) and macrophage inflammatory proteins (MIP) 1ß and 1α were consistently associated with lower FA and higher MD across white matter tracts. CONCLUSIONS: Elevated serum VEGF, MIP-1α, and MIP-1ß were associated with altered white matter microstructure. These blood biomarkers may help predict HIV-associated white matter damage.


Assuntos
Infecções por HIV , Substância Branca , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Substância Branca/diagnóstico por imagem , Fator A de Crescimento do Endotélio Vascular , Imagem de Tensor de Difusão/métodos , Infecções por HIV/complicações , Infecções por HIV/diagnóstico por imagem , Infecções por HIV/tratamento farmacológico , Estudos Transversais , Encéfalo/diagnóstico por imagem , Inflamação/diagnóstico por imagem , Anisotropia
17.
Ecotoxicol Environ Saf ; 263: 115364, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37586198

RESUMO

As the cheap and efficient catalysts, the iron-based catalysts have been considered as one of the most promising catalysts for peroxydisulfate (PDS) activation and the development of high-performance iron-based catalysts are attracting growing attentions. In this work, a magnetic Fe-based catalysts (Fe/NC-1000) was obtained by using Fe modified ZIF-8 as the precursor and used to activate the PDS for the degradation of perfluorooctane sulphonate (PFOS). Morphology and structure analysis showed that the resulted Fe/NC-1000 catalyst was displayed porous spheres (40-60 nm) and mainly composed of Fe0, FeNx and carbon. When Fe/NC-1000 was employed to activate the PDS (0.1 g/L of catalyst dosage, 0.5 g/L of PDS dosage and at initial pH of 4.6), the Fe/NC-1000/PDS system exhibited excellent efficiency (97.9 ± 0.1) % for PFOS (10 mg/L) degradation within 30 min. The quenching tests and EPR results revealed that the Fe/NC-1000/PDS system degraded PFOS primarily through singlet oxygen (1O2) evolution and electron-transfer process. Besides, based on the degradation byproducts determined by LC-MS-MS, the PFOS first occurred de-sulfonation to form PFOA, and then the resulted PFOA underwent stepwise defluorination in the Fe/NC-1000/PDS system. Density Functional Theory (DFT) calculations and electrochemistry tests strongly confirmed that Fe/NC-1000 exhibited high electron transfer efficiency, resulting in promoted performance on activating PDS. Importantly, the results of Ecological Structure-Activity Relationship (ECOSAR) analysis showed that the intermediates were lowly toxic during the PFOS degradation, manifesting a green process for PFOS removal. This study would provide more understandings for the persulfate activation process mediated by Fe-based catalysts for Perfluorinated alkyl substances (PFAS) elimination.


Assuntos
Fluorocarbonos , Ferro , Ferro/química , Eletroquímica , Oxigênio Singlete , Catálise
18.
Sensors (Basel) ; 23(17)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37687883

RESUMO

Three-dimensional reconstruction of the left myocardium is of great significance for the diagnosis and treatment of cardiac diseases. This paper proposes a personalized 3D reconstruction algorithm for the left myocardium using cardiac MR images by incorporating a residual graph convolutional neural network. The accuracy of the mesh, reconstructed using the model-based algorithm, is largely affected by the similarity between the target object and the average model. The initial triangular mesh is obtained directly from the segmentation result of the left myocardium. The mesh is then deformed using an iterated residual graph convolutional neural network. A vertex feature learning module is also built to assist the mesh deformation by adopting an encoder-decoder neural network to represent the skeleton of the left myocardium at different receptive fields. In this way, the shape and local relationships of the left myocardium are used to guide the mesh deformation. Qualitative and quantitative comparative experiments were conducted on cardiac MR images, and the results verified the rationale and competitiveness of the proposed method compared to related state-of-the-art approaches.


Assuntos
Cardiopatias , Imageamento Tridimensional , Humanos , Coração/diagnóstico por imagem , Miocárdio , Redes Neurais de Computação
19.
J Stroke Cerebrovasc Dis ; 32(8): 107185, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37186970

RESUMO

OBJECTIVE: To test the hypothesis that intracranial arterial calcification (IAC) is associated with intracranial large artery stenosis (ILAS) and a higher risk of vascular events and mortality. METHOD: We leveraged data from two cohorts, the New York-Presbyterian Hospital/Columbia University Irving Medical Center Stroke Registry Study (NYP/CUIMC-SRS) and the Northern Manhattan Study (NOMAS) to test our hypotheses. We measured IAC using CT scans of participants in both cohorts and expressed IAC as present (vs not) and in tertiles. For the CUIMC-SRS, demographic, clinical and ILAS status was collected retrospectively. In NOMAS, we used research brain MRI and MRA to define asymptomatic ILAS and covert brain infarcts(CBI). We built models adjusted for demographics and vascular risk factors for cross-sectional and longitudinal analyses. RESULTS: Cross-sectionally, IAC was associated with ILAS in both cohorts (OR 1.78, 95% CI: 1.16-2.73 for ILAS-related stroke in the NYP/CUIMC-SRS and OR 3.07, 95%CI 1.13-8.35 for ILAS-related covert brain infarcts in NOMAS). In a meta-analysis of both cohorts, IAC in the upper (HR 1.25, 95%CI 1.01-1.55) and middle tertile (HR 1.27, 95%CI 1.01-1.59) was associated with higher mortality compared with participants with no IAC. There were no longitudinal associations between IAC and risk of stroke or other vascular events. CONCLUSION: In these multiethnic populations, IAC is associated with symptomatic and asymptomatic ILAS as well as higher mortality. IAC may be a useful marker of higher mortality, the role of IAC as an imaging marker of risk of stroke is less certain.


Assuntos
Noma , Acidente Vascular Cerebral , Humanos , Estudos Transversais , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Artérias , Constrição Patológica
20.
Angew Chem Int Ed Engl ; 62(46): e202311816, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37743623

RESUMO

Herein, chiral deep eutectic solvents (DES) are prepared by lauric acid as hydrogen bond donors (HBD) and chiral menthol as hydrogen bond acceptors (HBA). When achiral fluorescent molecules are dopedin the menthol-based chiral DES, they emit circularly polarized luminescence (CPL) with handedness controlled by the molecular chirality (l or d) of menthol. Remarkably, the strategy is universal and a series of achiral fluorescent molecules can be endowed with CPL activity, showing a full-color and white CPL upon appropriate mixing, which paves the way to prepare white CPL materials. Interestingly, CPL appears only in a certain temperature range in the DES. Variable-temperature spectra and other characterization methods reveal that the H-bond network in the chiral DES plays an important role in inducing CPL. This work unveils how the interior structure as well as the hydrogen-bond network of a chiral DES can transfer its chirality to achiral luminophores for the first time and realizes a full-color and white CPL in a DES.

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