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1.
Cell ; 185(18): 3375-3389.e21, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35998627

RESUMEN

Systemic lupus erythematosus (SLE) is a complex autoimmune disease involving multiple immune cells. To elucidate SLE pathogenesis, it is essential to understand the dysregulated gene expression pattern linked to various clinical statuses with a high cellular resolution. Here, we conducted a large-scale transcriptome study with 6,386 RNA sequencing data covering 27 immune cell types from 136 SLE and 89 healthy donors. We profiled two distinct cell-type-specific transcriptomic signatures: disease-state and disease-activity signatures, reflecting disease establishment and exacerbation, respectively. We then identified candidate biological processes unique to each signature. This study suggested the clinical value of disease-activity signatures, which were associated with organ involvement and therapeutic responses. However, disease-activity signatures were less enriched around SLE risk variants than disease-state signatures, suggesting that current genetic studies may not well capture clinically vital biology. Together, we identified comprehensive gene signatures of SLE, which will provide essential foundations for future genomic and genetic studies.


Asunto(s)
Lupus Eritematoso Sistémico , Transcriptoma , Humanos , Lupus Eritematoso Sistémico/genética , Análisis de Secuencia de ARN
2.
Nature ; 602(7898): 606-611, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35197620

RESUMEN

Two-dimensional materials with monolayer thickness and extreme aspect ratios are sought for their high surface areas and unusual physicochemical properties1. Liquid exfoliation is a straightforward and scalable means of accessing such materials2, but has been restricted to sheets maintained by strong covalent, coordination or ionic interactions3-10. The exfoliation of molecular crystals, in which repeat units are held together by weak non-covalent bonding, could generate a greatly expanded range of two-dimensional crystalline materials with diverse surfaces and structural features. However, at first sight, these weak forces would seem incapable of supporting such intrinsically fragile morphologies. Against this expectation, we show here that crystals composed of discrete supramolecular coordination complexes can be exfoliated by sonication to give free-standing monolayers approximately 2.3 nanometres thick with aspect ratios up to approximately 2,500:1, sustained purely by apolar intermolecular interactions. These nanosheets are characterized by atomic force microscopy and high-resolution transmission electron microscopy, confirming their crystallinity. The monolayers possess complex chiral surfaces derived partly from individual supramolecular coordination complex components but also from interactions with neighbours. In this respect, they represent a distinct type of material in which molecular components are all equally exposed to their environment, as if in solution, yet with properties arising from cooperation between molecules, because of crystallinity. This unusual nature is reflected in the molecular recognition properties of the materials, which bind carbohydrates with strongly enhanced enantiodiscrimination relative to individual molecules or bulk three-dimensional crystals.


Asunto(s)
Microscopía de Fuerza Atómica , Microscopía Electrónica de Transmisión
3.
Nature ; 594(7861): 46-50, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34079140

RESUMEN

Moiré superlattices formed by van der Waals materials can support a wide range of electronic phases, including Mott insulators1-4, superconductors5-10 and generalized Wigner crystals2. When excitons are confined by a moiré superlattice, a new class of exciton emerges, which holds promise for realizing artificial excitonic crystals and quantum optical effects11-16. When such moiré excitons are coupled to charge carriers, correlated states may arise. However, no experimental evidence exists for charge-coupled moiré exciton states, nor have their properties been predicted by theory. Here we report the optical signatures of trions coupled to the moiré potential in tungsten diselenide/molybdenum diselenide heterobilayers. The moiré trions show multiple sharp emission lines with a complex charge-density dependence, in stark contrast to the behaviour of conventional trions. We infer distinct contributions to the trion emission from radiative decay in which the remaining carrier resides in different moiré minibands. Variation of the trion features is observed in different devices and sample areas, indicating high sensitivity to sample inhomogeneity and variability. The observation of these trion features motivates further theoretical and experimental studies of higher-order electron correlation effects in moiré superlattices.

4.
Plant Cell ; 34(11): 4255-4273, 2022 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-35775937

RESUMEN

Lipid droplets (LDs) stored during seed development are mobilized and provide essential energy and lipids to support seedling growth upon germination. Triacylglycerols (TAGs) are the main neutral lipids stored in LDs. The lipase SUGAR DEPENDENT 1 (SDP1), which hydrolyzes TAGs in Arabidopsis thaliana, is localized on peroxisomes and traffics to the LD surface through peroxisomal extension, but the underlying mechanism remains elusive. Here, we report a previously unknown function of a plant-unique endosomal sorting complex required for transport (ESCRT) component FYVE DOMAIN PROTEIN REQUIRED FOR ENDOSOMAL SORTING 1 (FREE1) in regulating peroxisome/SDP1-mediated LD turnover in Arabidopsis. We showed that LD degradation was impaired in germinating free1 mutant; moreover, the tubulation of SDP1- or PEROXIN 11e (PEX11e)-marked peroxisomes and the migration of SDP1-positive peroxisomes to the LD surface were altered in the free1 mutant. Electron tomography analysis showed that peroxisomes failed to form tubules to engulf LDs in free1, unlike in the wild-type. FREE1 interacted directly with both PEX11e and SDP1, suggesting that these interactions may regulate peroxisomal extension and trafficking of the lipase SDP1 to LDs. Taken together, our results demonstrate a pivotal role for FREE1 in LD degradation in germinating seedlings via regulating peroxisomal tubulation and SDP1 targeting.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Plantones/metabolismo , Peroxisomas/metabolismo , Proteínas de Arabidopsis/metabolismo , Gotas Lipídicas/metabolismo , Lipasa/metabolismo , Complejos de Clasificación Endosomal Requeridos para el Transporte/genética , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Lípidos , Hidrolasas de Éster Carboxílico/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
5.
BMC Genomics ; 25(1): 374, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627644

RESUMEN

BACKGROUND: Fatty liver hemorrhagic syndrome (FLHS) in the modern poultry industry is primarily caused by nutrition. Despite encouraging progress on FLHS, the mechanism through which nutrition influences susceptibility to FLHS is still lacking in terms of epigenetics. RESULTS: In this study, we analyzed the genome-wide patterns of trimethylated lysine residue 27 of histone H3 (H3K27me3) enrichment by chromatin immunoprecipitation-sequencing (ChIP-seq), and examined its association with transcriptomes in healthy and FLHS hens. The study results indicated that H3K27me3 levels were increased in the FLHS hens on a genome-wide scale. Additionally, H3K27me3 was found to occupy the entire gene and the distant intergenic region, which may function as silencer-like regulatory elements. The analysis of transcription factor (TF) motifs in hypermethylated peaks has demonstrated that 23 TFs are involved in the regulation of liver metabolism and development. Transcriptomic analysis indicated that differentially expressed genes (DEGs) were enriched in fatty acid metabolism, amino acid, and carbohydrate metabolism. The hub gene identified from PPI network is fatty acid synthase (FASN). Combined ChIP-seq and transcriptome analysis revealed that the increased H3K27me3 and down-regulated genes have significant enrichment in the ECM-receptor interaction, tight junction, cell adhesion molecules, adherens junction, and TGF-beta signaling pathways. CONCLUSIONS: Overall, the trimethylation modification of H3K27 has been shown to have significant regulatory function in FLHS, mediating the expression of crucial genes associated with the ECM-receptor interaction pathway. This highlights the epigenetic mechanisms of H3K27me3 and provides insights into exploring core regulatory targets and nutritional regulation strategies in FLHS.


Asunto(s)
Anomalías Múltiples , Anomalías Craneofaciales , Dieta con Restricción de Proteínas , Hígado Graso , Trastornos del Crecimiento , Defectos del Tabique Interventricular , Animales , Femenino , Histonas/metabolismo , Pollos/genética , Pollos/metabolismo , Epigénesis Genética , Hígado Graso/genética , Hígado Graso/veterinaria , Hemorragia/genética , Transcriptoma
6.
J Am Chem Soc ; 146(5): 3147-3159, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38279915

RESUMEN

Interlocked molecular assemblies constitute a captivating ensemble of chemical topologies, comprising two or more separate components that exhibit remarkably intricate structures. The interlocked molecular assemblies are typically identical, and heterointerlocked systems that comprise structurally distinct assemblies remain unexplored. Here, we demonstrate that metal-templated synthesis can be exploited to afford not only a homointerlocked cage but also a heterointerlocked cage. Treatment of a carboxylated 2,9-dimethyl-1,10-phenanthroline (dmp) or Cu(I) bis-dmp linker with a Ni4-p-tert-butylsulfonylcalix[4]arene cluster affords noninterlocked octahedron and quadruply interlocked double cages consisting of two identical tetragonal pyramids, respectively. In contrast, when a mixture of dmp and Cu(I) bis-dmp linkers is used, a quadruply heterointerlocked cage is produced, consisting of a tetragonal pyramid and an octahedron. With photoredox-active [Cu(dmp)2]+ in the structures, both interlocked cages exhibit remarkable performance as photocatalysts for atom transfer radical addition (ATRA) reactions of trifluoromethanesulfonyl chloride with alkenes or oxo-azidations of vinyl arenes. These interlocked structures serve the dual purpose of stabilizing photocatalytically active components against deactivation and encapsulating substrates within the cavity, resulting in yields comparable to or even surpassing those of their molecular counterparts. This work thus provides a new strategy that combines metal templating and nontemplating approaches to design new types of interlocked assemblies with intriguing architectures and properties.

7.
J Am Chem Soc ; 146(10): 6733-6743, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38418379

RESUMEN

Chiral covalent organic frameworks (CCOFs) have attracted extensive interest for their potential applications in various enantioselective processes. However, the exploitation of chirality-induced spin selectivity (CISS) that enables a new technology for the injection of spin polarized current without the need for a permanent magnetic layer within CCOFs remains a largely untapped area of research. Here, we demonstrate that, for the first time, COFs can be an attractive platform to develop spin filter materials with efficient CISS. This facilitates the design and synthesis of a new family of Zn(salen)-based 2D CCOFs, namely, CCOFs-9-12, by imine condensation of chiral 1,2-diaminocyclohexane and tri- or tetra(salicylaldehyde) derivatives. CCOF-9, distinguished by its unique C2 symmetric "armchair" tetrasubstituted pyrene conformation, exhibits the most pronounced chirality among these materials and serves as a solid-state host, enabling the enantioselective adsorption of racemic drugs with an enantiomeric excess (ee) of up to 97%. After substituting diamagnetic zinc(II) ions for paramagnetic cobalt(II), the resulting CCOF-9-Co not only retains its high crystallinity, porosity, and exceptional chirality but also exhibits enhanced conductivity, a crucial factor for the effective observation of CISS. Magnetic conductive atomic force microscopy showed that CCOF-9-Co exhibited a remarkable CISS effect with up to an 88-94% spin polarization ratio. This phenomenon is further confirmed by the increased intensity in the magnetic circular dichroism (MCD) when CCOF-9-Co is under an external magnetic field. This work therefore shows the tremendous potential of CCOFs for controlling spin selectivity and will stimulate the creation of new types of crystalline polymers with strong CISS effects for spin filters.

8.
J Am Chem Soc ; 146(12): 8407-8416, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38482804

RESUMEN

Although a variety of chiral porous framework materials have been reported, there are few examples known to combine molecular chirality, helicity, and three-dimensional (3D) intrinsically chiral topology in one structure, which is beneficial for chirality transfer and amplification. Here, we report the synthesis of the first two 3D covalent organic frameworks (COFs) with an intrinsic chiral qzd topology, which exhibit unusual integration of various homochiral and homohelical features. By imine condensation of 4-connected porphyrin tetraamines and 2-connected enantiopure diene dialdehyde, we prepared two isostructural COFs with a noninterpenetrated qzd topology. The specific geometry and conformation flexibility of the V-shaped diene linker control the alignment of square-planar porphyrin units with rotational linkages and facilitate the creation of homochiral extended porous structures that feature a helical arrangement of porphyrins. Post-synthetic metalation of CCOF 23 with Rh(I) affords a heterogeneous catalyst for the asymmetric Michael addition reaction of aryl boronic acids to 2-cyclohexenone, which shows higher enantioselectivities compared to their homogeneous counterparts, presumably due to the confined effect of helical channels. This finding will provide an impetus to explore multichirality materials, offering new insights into the generation and control of helicity, homochirality, and enantioselectivity in the solid state.

9.
J Am Chem Soc ; 146(1): 635-645, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38148276

RESUMEN

Covalent organic frameworks (COFs) have undergone extensive research as heterogeneous catalysts for a wide range of significant reactions, but they have not yet been investigated in the realm of electrochemical asymmetric catalysis, despite their recognition as an economical and sustainable strategy for producing enantiopure compounds. Here, we report a mixed-linker strategy to design multicomponent two-dimensional (2D) chiral COFs with tunable layer stacking for highly enantioselective electrocatalysis. By crystallizing mixtures of triamines with and without the MacMillan imidazolidinone catalyst or aryl substituent (ethyl and isopropyl) and a dialdehyde derivative of thieno-[3,2-b]thiophene, we synthesized and structurally characterized a series of three-component homochiral 2D COFs featuring either AA or ABC stacking. The stacking modes that can be synthetically controlled through steric tuning using different aryl substituents affect their chemical stability and electrochemical performance. With the MacMillan catalyst periodically appended on their channels, all three COFs with conductive thiophene moieties can be highly enantioselective and recyclable electrocatalysts for the asymmetric α-arylation of aldehydes, affording alkylated anilines with up to 97% enantiomeric excess by an anodic oxidation/organocatalytic protocol. Presumably due to their higher charge transfer ability, the ABC stacking COFs exhibit improved reactivity compared to the AA stacking analogue. This work therefore advances COFs as electrocatalysts for asymmetric catalysis and may facilitate the design of more redox-active crystalline organic polymers for electrochemical enantioselective processes.

10.
J Am Chem Soc ; 146(10): 6638-6651, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38415351

RESUMEN

Covalent organic cages are a prominent class of discrete porous architectures; however, their structural isomerism remains relatively unexplored. Here, we demonstrate the structural isomerism of chiral covalent organic cages that renders distinct enantioselective catalytic properties. Imine condensations of tetra-topic 5,10-di(3,5-diformylphenyl)-5,10-dihydrophenazine and ditopic 1,2-cyclohexanediamine produce two chiral [4 + 8] organic cage isomers with totally different topologies and geometries that depend on the orientations of four tetraaldehyde units with respect to each other. One isomer (PN-1) has an unprecedented Johnson-type J26 structure, whereas another (PN-2) adopts a tetragonal prismatic structure. After the reduction of the imine linkages, the cages are transformed into two amine bond-linked isomers PN-1R and PN-2R. After binding to Ni(II) ions, both can serve as efficient catalysts for asymmetric Michael additions, whereas PN-2R affords obviously higher enantioselectivity and reactivity than PN-1R presumably because of its large cavity and open windows that can concentrate reactants for the reactions. Density-functional theory (DFT) calculations further confirm that the enantioselective catalytic performance varies depending on the isomer.

11.
J Am Chem Soc ; 146(3): 2141-2150, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38191288

RESUMEN

Control of humidity within confined spaces is critical for maintaining air quality and human well-being, with implications for environments ranging from international space stations and pharmacies to granaries and cultural relic preservation sites. However, existing techniques rely on energy-intensive electrically driven equipment or complex temperature and humidity control (THC) systems, resulting in imprecision and inconvenience. The development of innovative techniques and materials capable of simultaneously meeting the stringent requirements of practical applications holds the key to creating intelligent and energy-efficient humidity control devices. In this study, we introduce chiral reticular chemistry as a tailored synthetic approach, targeting a highly porous hea topological framework characterized by intrinsic interpenetrating pore architecture. This groundbreaking design successfully circumvents the traditional compromise between the pore volume and hydrolytic stability. Our metal-organic framework (MOF) exhibits an extraordinary working capacity, setting a new record at 1.35 g g-1 within the relative humidity (RH) range of 40-60%, without exhibiting hysteresis. Consequently, it emerges as a state-of-the-art candidate for intelligent humidity regulation within confined spaces. Utilizing single-crystal X-ray measurements and molecular simulations, we unequivocally elucidate the mechanism of water clustering and pore filling, underscoring the pivotal role of the linker functionality in governing the water seeding process. Our findings represent a significant advancement in the field, paving the way for the development of highly efficient humidity control technologies and offering promising solutions for diverse real-world scenarios.

12.
J Am Chem Soc ; 146(13): 9205-9215, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38523309

RESUMEN

The nonfused thiophene-benzene-thiophene (TBT) unit offers advantages in obtaining low-cost organic photovoltaic (OPV) materials due to its simple structure. However, OPV cells, including TBT-based acceptors, exhibit significantly lower energy conversion efficiencies. Here, we introduce a novel approach involving the design and synthesis of three TBT-based acceptors by substituting different position-branched side chains on the TBT unit. In comparison to TBT-10 and TBT-11, TBT-13, which exclusively incorporates α-position branched side chains with a large steric hindrance, demonstrates a more planar and stable conformation. When blended with the donor PBQx-TF, TBT-13-based blend film achieves favorable π-π stacking and aggregation characteristics, resulting in excellent charge transfer performance in the corresponding device. Due to the simultaneous enhancements in short-circuit current density and fill factor, the TBT-13-based OPV cell obtains an outstanding efficiency of 16.1%, marking the highest value for the cells based on fully nonfused acceptors. Our work provides a practical molecular design strategy for high-performance and low-cost OPV materials.

13.
J Am Chem Soc ; 146(12): 8697-8705, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38478698

RESUMEN

Organic photovoltaic (OPV) cells have demonstrated remarkable success on the laboratory scale. However, the lack of cathode interlayer materials for large-scale production still limits their practical application. Here, we rationally designed and synthesized a cathode interlayer, named NDI-Ph. Benefiting from their well-modulated work function and self-doping effect, NDI-Ph-based binary OPV cells achieve an excellent power conversion efficiency (PCE) of 19.1%. NDI-Ph can be easily synthesized on a 100 g scale with a low cost of 1.96 $ g-1 using low-cost raw materials and a simple postprocessing method. In addition, the insensitivity to the film thickness of NDI-Ph enables it to maintain a high PCE at various coating speeds and solution concentrations, demonstrating excellent adaptability for high-throughput OPV cell manufacturing. As a result, a module with 21.9 cm2 active area achieves a remarkable PCEactive of 15.8%, underscoring the prospects of NDI-Ph in the large-scale production of OPV cells.

14.
Phys Rev Lett ; 132(3): 035102, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38307060

RESUMEN

We report the first experimental observation on the reduction of backward scatterings by an instantaneous broadband laser with 0.6% bandwidth in conditions of interest for inertial confinement fusion at the low-coherence Kunwu laser facility. The backscatter of stimulated Brillouin scattering (SBS) was robustly reduced by half at intensities of 1-5×10^{14} W/cm^{2} with the 0.53-µm broadband laser in comparison with the monochromatic laser. As SBS dominates energy loss of laser-plasma interactions, the reduction of that demonstrates the enhancement of laser-target coupling by the use of broadband laser. The mitigation of filamentation leads to the reduction of stimulated Raman backscattering at low intensities. In addition, the three-halves harmonic emission was reduced with the broadband laser as well.

15.
Chem Rev ; 122(9): 9078-9144, 2022 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-35344663

RESUMEN

In the past two decades, metal-organic frameworks (MOFs) or porous coordination polymers (PCPs) assembled from metal ions or clusters and organic linkers via metal-ligand coordination bonds have captivated significant scientific interest on account of their high crystallinity, exceptional porosity, and tunable pore size, high modularity, and diverse functionality. The opportunity to achieve functional porous materials by design with promising properties, unattainable for solid-state materials in general, distinguishes MOFs from other classes of materials, in particular, traditional porous materials such as activated carbon, silica, and zeolites, thereby leading to complementary properties. Scientists have conducted intense research in the production of chiral MOF (CMOF) materials for specific applications including but not limited to chiral recognition, separation, and catalysis since the discovery of the first functional CMOF (i.e., d- or l-POST-1). At present, CMOFs have become interdisciplinary between chirality chemistry, coordination chemistry, and material chemistry, which involve in many subjects including chemistry, physics, optics, medicine, pharmacology, biology, crystal engineering, environmental science, etc. In this review, we will systematically summarize the recent progress of CMOFs regarding design strategies, synthetic approaches, and cutting-edge applications. In particular, we will highlight the successful implementation of CMOFs in asymmetric catalysis, enantioselective separation, enantioselective recognition, and sensing. We envision that this review will provide readers a good understanding of CMOF chemistry and, more importantly, facilitate research endeavors for the rational design of multifunctional CMOFs and their industrial implementation.


Asunto(s)
Estructuras Metalorgánicas , Zeolitas , Catálisis , Humanos , Estructuras Metalorgánicas/química , Metales/química , Porosidad
16.
Am J Addict ; 33(3): 339-342, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37807121

RESUMEN

BACKGROUND AND OBJECTIVES: We provide an initial characterization of e-cigarette use among adult cancer patients. METHODS: Data were collected between November 2020 and August 2022 at a comprehensive cancer center. RESULTS: Relatively few (4.59%) of the assessed patients (n = 47,117) reported ever using e-cigarettes. Over one-third of current e-cigarette users reported being current combustible cigarette users. DISCUSSION AND CONCLUSIONS: These data suggest that e-cigarette use is uncommon but associated with other tobacco use among adult cancer patients. SCIENTIFIC SIGNIFICANCE: This is among the first comprehensive surveys of adult cancer patient e-cigarette use that details the types of e-cigarette and other tobacco products used by this population.

17.
BMC Musculoskelet Disord ; 25(1): 359, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38711079

RESUMEN

BACKGROUND: With the increasing incidence of steroid-induced necrosis of the femoral head (SNFH), numerous scholars have investigated its pathogenesis. Current evidence suggests that the imbalance between lipogenesis and osteoblast differentiation in bone marrow mesenchymal stem cells (BMSCs) is a key pathological feature of SNFH. MicroRNAs (miRNAs) have strong gene regulatory effects and can influence the direction of cell differentiation. N6-methyladenosine (m6A) is a prevalent epigenetic modification involved in diverse pathophysiological processes. However, knowledge of how miRNAs regulate m6A-related factors that affect BMSC differentiation is limited. OBJECTIVE: We aimed to investigate the role of miR27a in regulating the expression of YTHDF2 in BMSCs. METHODS: We compared miR27a, YTHDF2, and total m6A mRNA levels in SNFH-affected and control BMSCs. CCK-8 and TUNEL assays were used to assess BMSC proliferation and apoptosis. Western blotting and qRT‒PCR were used to measure the expression of osteogenic (ALP, RUNX2, and OCN) and lipogenic (PPARγ and C/EBPα) markers. Alizarin Red and Oil Red O staining were used to quantify osteogenic and lipogenic differentiation, respectively. miR27a was knocked down or overexpressed to evaluate its impact on BMSC differentiation and its relationship with YTHDF2. Bioinformatics analyses identified YTHDF2 as a differentially expressed gene in SNFH (ROC analysis) and revealed potential signaling pathways through GSEA. The effects of YTHDF2 silencing on the lipogenic and osteogenic functions of BMSCs were assessed. RESULTS: miR27a downregulation and YTHDF2 upregulation were observed in the SNFH BMSCs. miR27a knockdown/overexpression modulated YTHDF2 expression, impacting BMSC differentiation. miR27a silencing decreased m6A methylation and promoted osteogenic differentiation, while YTHDF2 silencing exerted similar effects. GSEA suggested potential signaling pathways associated with YTHDF2 in SNFH. CONCLUSION: miR27a regulates BMSC differentiation through YTHDF2, affecting m6A methylation and promoting osteogenesis. This finding suggests a potential therapeutic target for SNFH.


Asunto(s)
Adenosina/análogos & derivados , Diferenciación Celular , Células Madre Mesenquimatosas , MicroARNs , Osteogénesis , Proteínas de Unión al ARN , MicroARNs/genética , MicroARNs/metabolismo , Células Madre Mesenquimatosas/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Osteogénesis/genética , Humanos , Necrosis de la Cabeza Femoral/genética , Necrosis de la Cabeza Femoral/metabolismo , Necrosis de la Cabeza Femoral/inducido químicamente , Células Cultivadas , Apoptosis , Adenosina/metabolismo , Animales , Masculino , Metilación , Proliferación Celular , Lipogénesis/genética
18.
Lasers Med Sci ; 39(1): 113, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38656631

RESUMEN

PURPOSE: Melasma remains a refractory skin condition that needs to be actively explored. Azelaic acid has been used for decades as a topical agent to improve melasma through multiple mechanisms, however, there is a lack of research on its combination with laser therapy. This study evaluated the effectiveness of isolated treatment with topical 20% azelaic acid and its combination with 755-nm picosecond laser in facial melasma patients. METHODS: A randomized, evaluator-blinded, controlled study was conducted on 30 subjects with facial melasma in a single center from October 2021 to April 2022. All subjects received topical 20% azelaic acid cream (AA) for 24 weeks, and after 4 weeks, a hemiface was randomly assigned to receive 755-nm picosecond (PS) laser therapy once every 4 weeks for 3 treatments. Treatment efficacy was determined by mMASI score evaluations, dermoscopic assessment, reflectance confocal microscopy (RCM) assessments and patient's satisfaction assessments (PSA). RESULTS: Treatment with 20% azelaic acid, with or without picosecond laser therapy, significantly reduced the hemi-mMASI score (P < 0.0001) and resulted in higher patient satisfaction. Improvements in dermoscopic and RCM assessments were observed in both sides of the face over time, with no difference between the two sides. RCM exhibited better dentritic cell improvement in the combined treatment side. No patients had serious adverse effects at the end of treatment or during the follow-up period. CONCLUSION: The additional use of picosecond laser therapy showed no clinical difference except for subtle differences detected by RCM assessments.The study was registered in the Chinese Clinical Trial Registry (ChiCTR2100051294; 18 September 2021).


Asunto(s)
Ácidos Dicarboxílicos , Láseres de Estado Sólido , Melanosis , Humanos , Melanosis/terapia , Melanosis/radioterapia , Femenino , Ácidos Dicarboxílicos/uso terapéutico , Ácidos Dicarboxílicos/administración & dosificación , Adulto , Persona de Mediana Edad , Láseres de Estado Sólido/uso terapéutico , Masculino , Resultado del Tratamiento , Terapia por Luz de Baja Intensidad/métodos , Fármacos Dermatológicos/uso terapéutico , Fármacos Dermatológicos/administración & dosificación , Terapia Combinada , Satisfacción del Paciente , Administración Tópica , Método Simple Ciego
19.
Chem Biodivers ; 21(4): e202400256, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38361228

RESUMEN

The plant species, Sonchus wightianus DC., was historically used in China for both medicinal and dietary uses. In present study, seven new guaiane sesquiterpenoids (1-7) and one cytochalasin (8), along with five known guaianes (9-13) and two known cytochalasins (14 and 15), were isolated from the whole plants of S. wightianus. These guaianes showed structural variations in the substituents at C-8 and/or C-15, and compounds 6 and 7 are two sesquiterpenoid glycoside derivatives. Their structures were determined by extensive analysis of spectroscopic, electronic circular dichroism, and X-ray diffraction data, and chemical method. Biological tests revealed that compounds 5 and 8 are potent and selective immunosuppressive reagents.


Asunto(s)
Sesquiterpenos , Sonchus , Citocalasinas/química , Sesquiterpenos/farmacología , Sesquiterpenos/química , Difracción de Rayos X , China , Estructura Molecular
20.
J Craniofac Surg ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38861329

RESUMEN

Reconstructive surgery plays a crucial role in addressing congenital defects, posttraumatic deformities, and related conditions, providing transformative solutions for patients. Its primary goal is to restore or enhance damaged tissue structures, improving both functionality and appearance, and empowering individuals to lead fulfilling lives. Take, for example, a female patient who experienced a nasal infection after a cat bite. Despite initial treatment, she developed severe scar contractures and excessive scar tissue within her nostrils, significantly impacting her quality of life. Seeking assistance, she consulted the authors' plastic and reconstructive surgery team. By utilizing various flap techniques, the authors embarked on the intricate journey of reconstructing her nasal framework, ultimately restoring both form and function.

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