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1.
Comput Struct Biotechnol J ; 23: 1298-1310, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38560280

RESUMEN

In gestational diabetes mellitus (GDM), adipose tissue undergoes metabolic disturbances and chronic low-grade inflammation. Alternative polyadenylation (APA) is a post-transcriptional modification mechanism that generates mRNA with variable lengths of 3' untranslated regions (3'UTR), and it is associated with inflammation and metabolism. However, the role of APA in GDM adipose tissue has not been well characterized. In this study, we conducted transcriptomic and proteomic sequencing on subcutaneous and omental adipose tissues from both control and GDM patients. Using Dapars, a novel APA quantitative algorithm, we delineated the APA landscape of adipose tissue, revealing significant 3'UTR elongation of mRNAs in the GDM group. Omental adipose tissue exhibited a significant correlation between elongated 3'UTRs and reduced translation levels of genes related to metabolism and inflammation. Validation experiments in THP-1 derived macrophages (TDMs) demonstrated the impact of APA on translation levels by overexpressing long and short 3'UTR isoforms of a representative gene LRRC25. Additionally, LRRC25 was validated to suppress proinflammatory polarization in TDMs. Further exploration revealed two underexpressed APA trans-acting factors, CSTF3 and PPP1CB, in GDM omental adipose tissue. In conclusion, this study provides preliminary insights into the APA landscape of GDM adipose tissue. Reduced APA regulation in GDM omental adipose tissue may contribute to metabolic disorders and inflammation by downregulating gene translation levels. These findings advance our understanding of the molecular mechanisms underlying GDM-associated adipose tissue changes.

2.
BMC Plant Biol ; 24(1): 331, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664619

RESUMEN

BACKGROUND: Jasmine (Jasminum), renowned for its ornamental value and captivating fragrance, has given rise to numerous species and accessions. However, limited knowledge exists regarding the evolutionary relationships among various Jasminum species. RESULTS: In the present study, we sequenced seven distinct Jasminum species, resulting in the assembly of twelve high-quality complete chloroplast (cp) genomes. Our findings revealed that the size of the 12 cp genomes ranged from 159 to 165 kb and encoded 134-135 genes, including 86-88 protein-coding genes, 38-40 tRNA genes, and 8 rRNA genes. J. nudiflorum exhibited a larger genome size compared to other species, mainly attributed to the elevated number of forward repeats (FRs). Despite the typically conservative nature of chloroplasts, variations in the presence or absence of accD have been observed within J. sambac. The calculation of nucleotide diversity (Pi) values for 19 cp genomes indicated that potential mutation hotspots were more likely to be located in LSC regions than in other regions, particularly in genes ycf2, rbcL, atpE, ndhK, and ndhC (Pi > 0.2). Ka/Ks values revealed strong selection pressure on the genes rps2, atpA, rpoA, rpoC1, and rpl33 when comparing J. sambac with the three most closely related species (J. auriculatum, J. multiflorum, and J. dichotomum). Additionally, SNP identification, along with the results of Structure, PCA, and phylogenetic tree analyses, divided the Jasminum cp genomes into six groups. Notably, J. polyanthum showed gene flow signals from both the G5 group (J. nudiflorum) and the G3 group (J. tortuosum and J. fluminense). Phylogenetic tree analysis reflected that most species from the same genus clustered together with robust support in Oleaceae, strongly supporting the monophyletic nature of cp genomes within the genus Jasminum. CONCLUSION: Overall, this study provides comprehensive insights into the genomic composition, variation, and phylogenetic relationships among various Jasminum species. These findings enhance our understanding of the genetic diversity and evolutionary history of Jasminum.


Asunto(s)
Evolución Molecular , Variación Genética , Genoma del Cloroplasto , Jasminum , Filogenia , Jasminum/genética , Oleaceae/genética
3.
Clin Nutr ; 42(10): 1875-1888, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37625317

RESUMEN

BACKGROUND & AIMS: Exposure to a range of elements, air pollution, and specific dietary components in pregnancy has variously been associated with gestational diabetes mellitus (GDM) risk or infant neurodevelopmental problems. We measured a range of pregnancy exposures in maternal hair and/or infant cord serum and tested their relationship to GDM and infant neurodevelopment. METHODS: A total of 843 pregnant women (GDM = 224, Non-GDM = 619) were selected from the Complex Lipids in Mothers and Babies cohort study. Forty-eight elements in hair and cord serum were quantified using inductively coupled plasma-mass spectrometry analysis. Binary logistic regression was used to estimate the associations between hair element concentrations and GDM risk, while multiple linear regression was performed to analyze the relationship between hair/cord serum elements and air pollutants, diet exposures, and Bayley Scales of infant neurodevelopment at 12 months of age. RESULTS: After adjusting for maternal age, BMI, and primiparity, we observed that fourteen elements in maternal hair were associated with a significantly increased risk of GDM, particularly Ta (OR = 9.49, 95% CI: 6.71, 13.42), Re (OR = 5.21, 95% CI: 3.84, 7.07), and Se (OR = 5.37, 95% CI: 3.48, 8.28). In the adjusted linear regression model, three elements (Rb, Er, and Tm) in maternal hair and infant cord serum were negatively associated with Mental Development Index scores. For dietary exposures, elements were positively associated with noodles (Nb), sweetened beverages (Rb), poultry (Cs), oils and condiments (Ca), and other seafood (Gd). In addition, air pollutants PM2.5 (LUR) and PM10 were negatively associated with Ta and Re in maternal hair. CONCLUSIONS: Our findings highlight the potential influence of maternal element exposure on GDM risk and infant neurodevelopment. We identified links between levels of these elements in both maternal hair and infant cord serum related to air pollutants and dietary factors.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Diabetes Gestacional , Embarazo , Lactante , Femenino , Humanos , Diabetes Gestacional/epidemiología , Estudios de Cohortes , Sangre Fetal/química , Contaminación del Aire/efectos adversos , Contaminantes Atmosféricos/análisis , Ingestión de Alimentos
4.
Nat Commun ; 14(1): 2465, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37117203

RESUMEN

The fabrication of one-dimensional (1D) magnetic systems on solid surfaces, although of high fundamental interest, has yet to be achieved for a crossover between two-dimensional (2D) magnetic layers and their associated 1D spin chain systems. In this study, we report the fabrication of 1D single-unit-cell-width CrCl3 atomic wires and their stacked few-wire arrays on the surface of a van der Waals (vdW) superconductor NbSe2. Scanning tunneling microscopy/spectroscopy and first-principles calculations jointly revealed that the single wire shows an antiferromagnetic large-bandgap semiconducting state in an unexplored structure different from the well-known 2D CrCl3 phase. Competition among the total energies and nanostructure-substrate interfacial interactions of these two phases result in the appearance of the 1D phase. This phase was transformable to the 2D phase either prior to or after the growth for in situ or ex situ manipulations, in which the electronic interactions at the vdW interface play a nontrivial role that could regulate the dimensionality conversion and structural transformation between the 1D-2D CrCl3 phases.

5.
J Phys Chem Lett ; 12(44): 10808-10814, 2021 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-34726059

RESUMEN

On-surface fabrication of two-dimensional (2D) metal organic frameworks (MOFs) has been continuously attracting attentions for years. However, the synthesis of 2D MOFs with large-amplitude flexibility was rarely carried out since the bonding configurations in the coordination nodes are typically highly directional. Here we demonstrate that single alkali ions, which are fully isotropic in ionic bonding, can act as pivot joints for constructing tunable 2D MOFs by bonding to dihalogen groups in organic molecules. We take 2,3,6,7,10,11-hexabromotriphenylene, a 3-fold polycyclic molecule with three ortho-dibromo groups, and sodium (Na) atoms as a model system and successfully construct Na-based MOFs on Au(111) surface. The deflection angle of the Na coordination nodes is variable in an unprecedentedly large range between ±36° that allows the construction of multiple 2D MOF architectures. Such a flexible alkali-halogen bonding may provide a unique toolbox for designing and constructing more tunable MOFs by choosing various alkali atoms and halogen moieties.

6.
Nat Commun ; 10(1): 3374, 2019 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-31358744

RESUMEN

Collective molecular physical properties can be enhanced from their intrinsic characteristics by templating at material interfaces. Here we report how a black phosphorous (BP) substrate concatenates a nearly-free-electron (NFE) like conduction band of a C60 monolayer. Scanning tunneling microscopy reveals the C60 lowest unoccupied molecular orbital (LUMO) band is strongly delocalized in two-dimensions, which is unprecedented for a molecular semiconductor. Experiment and theory show van der Waals forces between C60 and BP reduce the inter-C60 distance and cause mutual orientation, thereby optimizing the π-π wave function overlap and forming the NFE-like band. Electronic structure and carrier mobility calculations predict that the NFE band of C60 acquires an effective mass of 0.53-0.70 me (me is the mass of free electrons), and has carrier mobility of ~200 to 440 cm2V-1s-1. The substrate-mediated intermolecular van der Waals interactions provide a route to enhance charge delocalization in fullerenes and other organic semiconductors.

7.
Sci Bull (Beijing) ; 64(5): 293-300, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36659592

RESUMEN

Two-dimensional magnets have received increasing attention since Cr2Ge2Te6 and CrI3 were experimentally exfoliated and measured in 2017. Although layered ferromagnetic metals were demonstrated at room temperature, a layered ferromagnetic semiconductor with high Curie temperature (Tc) is yet to be unveiled. Here, we theoretically predicted a family of high Tc ferromagnetic monolayers, namely MnNX and CrCX (X = Cl, Br and I; C = S, Se and Te). Their Tc values were predicted from over 100 K to near 500 K with Monte Carlo simulations using an anisotropic Heisenberg model. Eight members among them show semiconducting bandgaps varying from roughly 0.23 to 1.85 eV. These semiconducting monolayers also show extremely large anisotropy, i.e. ∼101 for effective masses and ∼102 for carrier mobilities, along the two in-plane lattice directions of these layers. Additional orbital anisotropy leads to a spin-locked linear dichroism, in different from previously known circular and linear dichroisms in layered materials. Together with the mobility anisotropy, it offers a spin-, dichroism- and mobility-anisotropy locking. These results manifest the potential of this 2D family for both fundamental research and high performance spin-dependent electronic and optoelectronic devices.

8.
Nanoscale ; 10(47): 22263-22269, 2018 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-30465580

RESUMEN

Few-layer tellurium is an emerging quasi-one-dimensional layered material. The striking feature of Te is its presence as various few-layer allotropes (α-δ). Although these allotropes offer substantially different physical properties, only the α phase has been synthesized in neutral few-layers as it is so far the most stable few-layer form. Herein, we show that hole or electron doping could maintain a certain Te phase. The ß, α, γ and δ phases appear as the most stable forms of Te bilayer, in sequence, with bandgap variations over 1 eV. In Te trilayer, a novel metallic chiral α + δ phase emerges, leading to the appearance of chirality. Transitions among these phases, understood at the wavefunction level, are accompanied by the emergence or elimination of inversion centers (α-ß, α-γ, α-α + δ), structural anisotropy (α-γ, γ-δ) and chirality (α-α + δ), which could result in substantial changes in optical and other properties. In light of these findings, our work opens a new avenue for stabilizing different allotropes of layered materials; this is crucial for using their outstanding properties. This study also suggests the possibility of building mono-elemental electronic and optoelectronic heterostructures or devices, which are attractive for future applications in electronics.

9.
ACS Nano ; 12(5): 4853-4860, 2018 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-29688700

RESUMEN

Atomic substitution offers an important route to achieve compositionally engineered two-dimensional nanostructures and their heterostructures. Despite the recent research progress, the fundamental understanding of the reaction mechanism has still remained unclear. Here, we reveal the atomic substitution mechanism of two-dimensional atomic layered materials. We found that the atomic substitution process depends on the varying lattice constant (strain) in monolayer crystals, dominated by two strain-tuning (self-promoted and self-limited) mechanisms using density functional theory calculations. These mechanisms were experimentally confirmed by the controllable realization of a graded substitution ratio in the monolayers by controlling the substitution temperature and time and further theoretically verified by kinetic Monte Carlo simulations. The strain-tuning atomic substitution processes are of general importance to other two-dimensional layered materials, which offers an interesting route for tailoring electronic and optical properties of these materials.

10.
Nanoscale ; 8(15): 8324-32, 2016 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-27035503

RESUMEN

Anisotropic two-dimensional (2D) van der Waals (vdW) layered materials, with both scientific interest and application potential, offer one more dimension than isotropic 2D materials to tune their physical properties. Various physical properties of 2D multi-layer materials are modulated by varying their stacking orders owing to significant interlayer vdW coupling. Multilayer rhenium disulfide (ReS2), a representative anisotropic 2D material, was expected to be randomly stacked and lack interlayer coupling. Here, we demonstrate two stable stacking orders, namely isotropic-like (IS) and anisotropic-like (AI) N layer (NL, N > 1) ReS2 are revealed by ultralow- and high-frequency Raman spectroscopy, photoluminescence and first-principles density functional theory calculation. Two interlayer shear modes are observed in AI-NL-ReS2 while only one shear mode appears in IS-NL-ReS2, suggesting anisotropic- and isotropic-like stacking orders in IS- and AI-NL-ReS2, respectively. This explicit difference in the observed frequencies identifies an unexpected strong interlayer coupling in IS- and AI-NL-ReS2. Quantitatively, the force constants of them are found to be around 55-90% of those of multilayer MoS2. The revealed strong interlayer coupling and polytypism in multi-layer ReS2 may stimulate future studies on engineering physical properties of other anisotropic 2D materials by stacking orders.

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