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1.
J Cell Mol Med ; 28(1): e18023, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38146147

RESUMO

In recent years, an increasing number of observational studies have revealed an association between gut microbiota composition and psoriasis patients. However, whether this association reflects a causal relationship remains unclear. This study aimed to identify the causal relationship between gut microbiota and psoriasis through relevant research. In order to determine whether gut microbiota and psoriasis are causally related, we conducted a Mendelian randomization analysis using summary statistics from genome-wide association studies (GWAS). As the exposure factor, we used summary statistics data from a GWAS study conducted by the MiBioGen Consortium, including 18,340 individuals with whole-genome gut microbiota composition, and data from the FinnGen GWAS study on psoriasis, including 9267 patients and 364,071 controls as the disease outcome. Two-sample Mendelian randomization analysis was subsequently performed with inverse variance weighted, MR-Egger and weighted median, while sensitivity analyses were conducted to address heterogeneity and horizontal pleiotropy. The IVW results confirmed the causal relationship between certain gut microbiota groups and psoriasis. Specifically, family Veillonellaceae (OR = 1.162, 95% CI: 1.038-1.301, p = 0.009), genus Candidatus Soleaferrea (OR = 1.123, 95% CI: 1.011-1.247, p = 0.030) and genus Eubacterium fissicatena group (OR = 0.831, 95% CI: 0.755-0.915, p = 0.00016) showed significant associations. Sensitivity analysis did not reveal any abnormalities in SNPs. Currently, we have found some causal relationship between the gut microbiota and psoriasis. However, the study needs further RCTs for further validation.


Assuntos
Microbioma Gastrointestinal , Psoríase , Humanos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único
2.
Expert Rev Mol Med ; 26: e10, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38659380

RESUMO

Autoimmune diseases are pathological autoimmune reactions in the body caused by various factors, which can lead to tissue damage and organ dysfunction. They can be divided into organ-specific and systemic autoimmune diseases. These diseases usually involve various body systems, including the blood, muscles, bones, joints and soft tissues. The transient receptor potential (TRP) and PIEZO receptors, which resulted in David Julius and Ardem Patapoutian winning the Nobel Prize in Physiology or Medicine in 2021, attracted people's attention. Most current studies on TRP and PIEZO receptors in autoimmune diseases have been carried out on animal model, only few clinical studies have been conducted. Therefore, this study aimed to review existing studies on TRP and PIEZO to understand the roles of these receptors in autoimmune diseases, which may help elucidate novel treatment strategies.


Assuntos
Doenças Autoimunes , Canais Iônicos , Canais de Potencial de Receptor Transitório , Humanos , Doenças Autoimunes/metabolismo , Doenças Autoimunes/imunologia , Animais , Canais Iônicos/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo
3.
Inflammopharmacology ; 31(4): 1823-1838, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37012581

RESUMO

BACKGROUND: Primary Sjögren's syndrome (pSS) is an autoimmune disease that leads to the destruction of exocrine glands and multisystem lesions. Abnormal proliferation, apoptosis, and differentiation of CD4+ T cells are key factors in the pathogenesis of pSS. Autophagy is one of the important mechanisms to maintain immune homeostasis and function of CD4+ T cells. Human umbilical cord mesenchymal stem cell-derived exosomes (UCMSC-Exos) may simulate the immunoregulation of MSCs while avoiding the risks of MSCs treatment. However, whether UCMSC-Exos can regulate the functions of CD4+ T cells in pSS, and whether the effects via the autophagy pathway remains unclear. METHODS: The study analyzed retrospectively the peripheral blood lymphocyte subsets in pSS patients, and explored the relationship between lymphocyte subsets and disease activity. Next, peripheral blood CD4+ T cells were sorted using immunomagnetic beads. The proliferation, apoptosis, differentiation, and inflammatory factors of CD4+ T cells were determined using flow cytometry. Autophagosomes of CD4+ T cells were detected using transmission electron microscopy, autophagy-related proteins and genes were detected using western blotting or RT-qPCR. RESULTS: The study demonstrated that the peripheral blood CD4+ T cells decreased in pSS patients, and negatively correlated with disease activity. UCMSC-Exos inhibited excessive proliferation and apoptosis of CD4+ T cells in pSS patients, blocked them in the G0/G1 phase, inhibited them from entering the S phase, reduced the Th17 cell ratio, elevated the Treg ratio, inhibited IFN-γ, TNF-α, IL-6, IL-17A, and IL-17F secretion, and promoted IL-10 and TGF-ß secretion. UCMSC-Exos reduced the elevated autophagy levels in the peripheral blood CD4+ T cells of patients with pSS. Furthermore, UCMSC-Exos regulated CD4+ T cell proliferation and early apoptosis, inhibited Th17 cell differentiation, promoted Treg cell differentiation, and restored the Th17/Treg balance in pSS patients through the autophagy pathway. CONCLUSIONS: The study indicated that UCMSC-Exos exerts an immunomodulatory effect on the CD4+ T cells, and maybe as a new treatment for pSS.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Síndrome de Sjogren , Humanos , Exossomos/metabolismo , Exossomos/patologia , Estudos Retrospectivos , Células Th17 , Fatores Imunológicos/metabolismo
4.
Phys Rev Lett ; 129(5): 056803, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35960565

RESUMO

Strain-induced pseudomagnetic fields can mimic real magnetic fields to generate a zero-magnetic-field analog of the Landau levels (LLs), i.e., the pseudo-Landau levels (PLLs), in graphene. The distinct nature of the PLLs enables one to realize novel electronic states beyond what is feasible with real LLs. Here, we show that it is possible to realize exotic electronic states through the coupling of zeroth PLLs in strained graphene. In our experiment, nanoscale strained structures embedded with PLLs are generated along a one-dimensional (1D) channel of suspended graphene monolayer. Our results demonstrate that the zeroth PLLs of the strained structures are coupled together, exhibiting a serpentine pattern that snakes back and forth along the 1D suspended graphene monolayer. These results are verified theoretically by large-scale tight-binding calculations of the strained samples. Our result provides a new approach to realizing novel quantum states and to engineering the electronic properties of graphene by using localized PLLs as building blocks.

5.
J Med Syst ; 46(12): 96, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36380246

RESUMO

Petabytes of health data are collected annually across the globe in electronic health records (EHR), including significant information stored as unstructured free text. However, the lack of effective mechanisms to securely share clinical text has inhibited its full utilization. We propose a new method, DataSifterText, to generate partially synthetic clinical free-text that can be safely shared between stakeholders (e.g., clinicians, STEM researchers, engineers, analysts, and healthcare providers), limiting the re-identification risk while providing significantly better utility preservation than suppressing or generalizing sensitive tokens. The method creates partially synthetic free-text data, which inherits the joint population distribution of the original data, and disguises the location of true and obfuscated words. Under certain obfuscation levels, the resulting synthetic text was sufficiently altered with different choices, orders, and frequencies of words compared to the original records. The differences were comparable to machine-generated (fully synthetic) text reported in previous studies. We applied DataSifterText to two medical case studies. In the CDC work injury application, using privacy protection, 60.9-86.5% of the synthetic descriptions belong to the same cluster as the original descriptions, demonstrating better utility preservation than the naïve content suppressing method (45.8-85.7%). In the MIMIC III application, the generated synthetic data maintained over 80% of the original information regarding patients' overall health conditions. The reported DataSifterText statistical obfuscation results indicate that the technique provides sufficient privacy protection (low identification risk) while preserving population-level information (high utility).


Assuntos
Registros Eletrônicos de Saúde , Privacidade , Humanos
6.
Angew Chem Int Ed Engl ; 60(20): 11173-11179, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33650282

RESUMO

The first observation of surface metallization of TiO2-x induced by fluoride ions is presented. The emerging metallic states are contributed by the 3d orbital of surface Ti and the 2p orbital of surface bridging F, which are intrinsically originated from the strong electron repulsion between F- and adjacent Ti3+ . The metalized TiO2-x with reduced work function and downward band bending possesses high electron-donating power to supported Ru species via atomic-scale ohmic contacts, exhibiting unprecedented photocatalytic performances for ammonia synthesis across the entire solar spectrum region (200-1550 nm) at room temperature. Mechanism and kinetic analysis revealed that the loaded Ru could behave as efficient electron sinks to accumulate photogenerated electrons and that the metallic surface markedly enhanced the dissociation of H2 and N2 by the hot electrons generated by the visible or even infrared light irradiation.

7.
Phys Chem Chem Phys ; 21(15): 7750-7755, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30681678

RESUMO

Two-dimensional CrI3 has attracted much attention as it is reported to be a ferromagnetic semiconductor with a Curie temperature of around 45 K. By performing first-principles calculations, we find that the magnetic ground state of CrI3 is variable under biaxial strain. Our theoretical investigations show that the ground state of monolayer CrI3 is ferromagnetic under compression, but becomes antiferromagnetic under tension. Particularly, the transition occurs under a feasible in-plane strain of around 1.8%. Accompanied by the transition of the magnetic ground state, CrI3 undergoes a transition from magnetic-metal to half-metal to half-semiconductor to spin-relevant semiconductor when the strain varies from -15% to 10%. We attribute these transitions to the variation of the d-orbitals of Cr atoms and the p-orbitals of I atoms. Generally, we report a series of magnetic and electronic phase transitions in strained CrI3, which will help both theoretical and experimental researchers in further understanding the tunable electronic and magnetic properties of CrI3 and its analogs.

8.
Phys Chem Chem Phys ; 20(10): 7167-7172, 2018 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-29513307

RESUMO

With the continuous expansion of the family of two-dimensional (2D) materials, flexible electronics based on 2D materials have quickly emerged. Theoretically, predicting the transport properties of the flexible devices made up of 2D materials using first principles is of great importance. Using density functional theory combined with the non-equilibrium Green's function formalism, we calculated the transport properties of all-phosphorus flexible devices with non-collinear electrodes, and the results predicted that the device with compressed metallic phosphorene electrodes sandwiching a P-type semiconducting phosphorene shows a better and robust conducting behavior against the bending of the semiconducting region when the angle between the two electrodes is less than 45°, which indicates that this system is very promising for flexible electronics. The calculation of a quantum transport system with non-collinear electrodes demonstrated in this work will provide more interesting information on mesoscopic material systems and related devices.

9.
ACS Appl Mater Interfaces ; 16(29): 38111-38123, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39007495

RESUMO

The catalytic deoxygenation of phenolic compounds is a crucial step in the valorization of biomass resources, which can effectively enhance the heating value and stability of primary biofuel. In this study, the catalytic mechanism of four Heusler alloy catalysts for the direct deoxidation pathway of phenol was studied through electronic structure regulation by element occupation. We found that Heusler alloys catalysts exhibit excellent catalytic activity in the dissociation activation of H2 and the cleavage of aryl hydroxyl bond (CAr-OH) bonds. The energy barriers for the direct cleavage of the CAr-OH bond in phenol on Ni2MoAl, Co2MoAl, Ni2NbAl and Ni2MoGa catalysts are 0.86, 0.95, 1.09, and 1.28 eV, respectively. And Y element of the X2YZ catalyst has a significant impact on this reaction, while the X element has a complex influence on the hydrogenation step of the unsaturated benzene ring. Microkinetic analysis further substantiates that the phenol (CAr-OH) bond cleavage step in the reaction exhibits a fast reaction rate and high extent of reaction. The reaction of hydroxyl hydrogenation to produce water exhibits the highest energy barrier, serving as the rate-determining step of the entire reaction. This issue could potentially be addressed by further fine-tuning the electronic structure.

10.
Anim Biosci ; 37(7): 1156-1167, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38665092

RESUMO

OBJECTIVE: MicroRNAs (miRNAs) are endogenous non-coding RNAs that can play a role in the post-transcriptional regulation of mammalian preadipocyte differentiation. However, the precise functional mechanism of its regulation of fat metabolism is not fully understood. METHODS: We identified bta-miR-365-3p, which specifically targets the 3' untranslated region (3'UTR) of the FK506-binding protein 5 (FKBP5), and verified its mechanisms for regulating expression and involvement in adipogenesis. RESULTS: In this study, we found that the overexpression of bta-miR-365-3p significantly decreased the lipid accumulation and triglyceride content in the adipocytes. Compared to inhibiting bta-miR-36 5-3p group, overexpression of bta-miR-365-3p can inhibit the expression of adipocyte differentiation-related genes C/EBPα and PPARγ. The dualluciferase reporter system further validated the targeting relationship between bta-miR-365-3p and FKBP5. FKBP5 mRNA and protein expression were detected by quantitative real-time polymerase chain reaction and Western blot. Overexpression of bta-miR-365-3p significantly down-regulated FKBP5 expression, while inhibition of bta-miR-365-3p showed the opposite, indicating that bta-miR-365-3p negatively regulates FKBP5. Adenosine 5'-monophosphate (AMP)-activated protein kinase/mammalian target of rapamycin (AMPK/mTOR) signaling pathway is closely related to the regulation of cell growth and is involved in the development of bovine adipocytes. In this study, overexpression of bta-miR-365-3p significantly inhibited mRNA and protein expression of AMPK, mTOR, and SREBP1 genes, while the inhibition of bta-miR-365-3p expression was contrary to these results. Overexpression of FKBP5 significantly upregulated AMPK, mTOR, and SREBP1 gene expression, while inhibition of FKBP5 expression was contrary to the above experimental results. CONCLUSION: In conclusion, these results indicate that bta-miR-365-3p may be involved in the AMPK/mTOR signaling pathway in regulating Yanbian yellow cattle preadipocytes differentiation by targeting the FKBP5 gene.

11.
J Mater Chem B ; 11(16): 3511-3536, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37066670

RESUMO

Mesenchymal stem cells (MSCs) have long been regarded as a potential treatment in regenerative medicine. However, due to the lack of effective methods to track and regulate the behavior of implanted MSCs, their application has been greatly limited. Carbon dots (CDs), as a new type of zero-dimensional carbon-based nanomaterial, have attracted extensive attention as nanoprobes, carriers and agents. The focus of this review is to clarify the noninvasive tracing of MSCs by CD-based nanoprobes, including conventional and dual modality imaging, and introduce several means to adjust the labeling performance. The effects of CDs on the differentiation behavior of MSCs and their underlying mechanism are summarized. As an excellent delivery carrier, CDs can easily carry genes and direct MSCs to differentiate. Other biological effects of CDs as agents, such as anti-inflammatory, antibacterial, photodynamic and photothermal effects, are also introduced. Finally, the significant therapeutic effect of the combination of CDs and MSCs, the existing problems of CDs and the future development direction are proposed. This review aims to inform researchers in materials science, biology and medicine to fully exploit the potential of CDs and purposefully modified MSCs, so as to provide some ideas for the application of engineered cell therapy in clinical transformation.


Assuntos
Células-Tronco , Carbono/química , Nanoestruturas , Diferenciação Celular , Humanos , Animais , Medicina Regenerativa , Técnicas de Transferência de Genes
12.
J Mater Chem B ; 11(23): 5094-5100, 2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37221873

RESUMO

Surface functionalization can effectively affect the properties of carbon dots (CDs), for example, improved solubility and dispersibility as well as enhanced selectivity and sensitivity. However, it is still a challenging task to tailor one or more specific functionalities of CDs via precise surface modification. In this study, click chemistry is applied to engineer CD surface functionalization, where the fluorescent molecule Rhodamine B (RhB) can be efficiently grafted onto the glucose-based bare CDs. The reaction process is quantitatively analyzed, which provides the basic theory for the functionalization of glucose-based CDs by double fluorescent molecules, namely RhB and Cy7. The fluorescence behavior of CDs can be accurately regulated by adjusting the molar ratio of the two molecules. The results of cell proliferation and apoptosis behavior of functionalized carbon dots show that the linkers (triazole structure) introduced by click chemistry have good biocompatibility. This quantitative and multifunctional modification method of CDs has undoubtedly greatly expanded its application field, especially in biological and medical aspects.


Assuntos
Química Click , Corantes Fluorescentes , Corantes Fluorescentes/química , Carbono/química , Espectrometria de Fluorescência , Apoptose
13.
Sci Rep ; 13(1): 22543, 2023 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-38110541

RESUMO

Metabolic abnormalities constitute a significant characteristic of systemic lupus erythematosus (SLE). We utilised a two-sample Mendelian randomisation (MR) study to evaluate the potential causal association between 486 blood metabolites and SLE. Exposure data at the metabolite level were extracted from 7824 European Genome-wide association studies (GWAS). Preliminary analysis utilised SLE GWAS data from FinnGen. The primary method for causal analysis relied on random inverse variance weighting (IVW). To ensure robustness, sensitivity analyses included the Cochran Q test, MR-Egger intercept test, MR-PRESSO, and leave-one-out analysis. Steiger testing and linkage disequilibrium score regression were employed to validate the identified metabolites. This study identified 12 metabolites, comprising six known chemical structures: 1,5-anhydroglucitol(1,5-AG) [odds ratio (OR) = 0.100, 95% confidence interval (CI): 0.015-0.773, P = 0.027), gamma-glutamylthreonine (OR = 0.077, 95% CI: 0.010-0.574, P = 0.012), 5-dodecenoate(12:1n7) (OR = 0.205, 95% CI: 0.061-0.685, P = 0.010), linoleoylglycerophosphoethanolamine * (OR = 0.159, 95% CI: 0.027-0.933, P = 0.044), erythrose (OR = 88.331,95% CI:1.098-63.214, P = 0.040) and 1-, adrenate (22:4n6) (OR = 9.876, 95% CI: 1.753-55.639, P = 0.001)]. Additionally, we found associations between SLE and six unknown chemical structures: X-06351 (OR = 0.071, 95% CI: 0.006-0.817, P = 0.034), X-10810 (OR = 4.268 95% CI: 1.260-14.459, P = 0.020), X-11412 (OR = 5.418 95% CI: 1.068-27.487, P = 0.041), X-11905 (OR = 0.551, 95%CI: 0.304-0.997, P = 0.049), X-12038 (OR = 0.178 95%CI: 0.032-0.988, P = 0.045), X-12217 (OR = 0.174 95%CI: 0.044-0.680, P = 0.014). This study offers evidence supporting a causal relationship between SLE and 12 circulating metabolites, six of which have known chemical structures and six that remain unidentified. These findings introduce a new perspective for further exploration of SLE mechanisms.


Assuntos
Estudo de Associação Genômica Ampla , Lúpus Eritematoso Sistêmico , Humanos , Análise da Randomização Mendeliana , Desequilíbrio de Ligação , Lúpus Eritematoso Sistêmico/genética , Nonoxinol
14.
Stem Cell Res Ther ; 14(1): 381, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-38124129

RESUMO

With the continuous improvement of human technology, the medical field has gradually moved from molecular therapy to cellular therapy. As a safe and effective therapeutic tool, cell therapy has successfully created a research boom in the modern medical field. Mesenchymal stem cells (MSCs) are derived from early mesoderm and have high self-renewal and multidirectional differentiation ability, and have become one of the important cores of cell therapy research by virtue of their immunomodulatory and tissue repair capabilities. In recent years, the application of MSCs in various diseases has received widespread attention, but there are still various problems in the treatment of MSCs, among which the heterogeneity of MSCs may be one of the causes of the problem. In this paper, we review the correlation of MSCs heterogeneity to provide a basis for further reduction of MSCs heterogeneity and standardization of MSCs and hope to provide a reference for cell therapy.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Humanos , Terapia Baseada em Transplante de Células e Tecidos , Diferenciação Celular
15.
Eur J Med Chem ; 246: 114940, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36462441

RESUMO

Bruton's tyrosine kinase (BTK) plays a crucial role in adaptive and immune responses by modulating B-cell, Fc, toll-like, and chemokine receptor signaling pathways. BTK inhibition is a promising therapeutic approach for the treatment of inflammatory and autoimmune diseases. The development of novel, highly selective, and less toxic BTK inhibitors may be beneficial for the treatment of autoimmune diseases with unmet medical needs. In this study, structure-based drug design was used to discover a series of novel, potent, and selective covalent BTK inhibitors with a 1,4,5,6,8-pentaazaacenaphthylen scaffold. Among them, compound 36R exhibited high kinase selectivity, long target occupancy time, appropriate pharmacokinetic properties, and dose-dependent efficacy in a rat model of collagen-induced arthritis. Therefore, 36R is a novel BTK inhibitor requiring further development for the treatment of autoimmune diseases.


Assuntos
Artrite Reumatoide , Desenho de Fármacos , Ratos , Animais , Tirosina Quinase da Agamaglobulinemia , Artrite Reumatoide/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/farmacocinética
16.
JMIR Biomed Eng ; 8: e46653, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-38875693

RESUMO

BACKGROUND: The incentive spirometer is a basic and common medical device from which electronic health care data cannot be directly collected. As a result, despite numerous studies investigating clinical use, there remains little consensus on optimal device use and sparse evidence supporting its intended benefits such as prevention of postoperative respiratory complications. OBJECTIVE: The aim of the study is to develop and test an add-on hardware device for data capture of the incentive spirometer. METHODS: An add-on device was designed, built, and tested using reflective optical sensors to identify the real-time location of the volume piston and flow bobbin of a common incentive spirometer. Investigators manually tested sensor level accuracies and triggering range calibrations using a digital flowmeter. A valid breath classification algorithm was created and tested to determine valid from invalid breath attempts. To assess real-time use, a video game was developed using the incentive spirometer and add-on device as a controller using the Apple iPad. RESULTS: In user testing, sensor locations were captured at an accuracy of 99% (SD 1.4%) for volume and 100% accuracy for flow. Median and average volumes were within 7.5% (SD 6%) of target volume sensor levels, and maximum sensor triggering values seldom exceeded intended sensor levels, showing a good correlation to placement on 2 similar but distinct incentive spirometer designs. The breath classification algorithm displayed a 100% sensitivity and a 99% specificity on user testing, and the device operated as a video game controller in real time without noticeable interference or delay. CONCLUSIONS: An effective and reusable add-on device for the incentive spirometer was created to allow the collection of previously inaccessible incentive spirometer data and demonstrate Internet-of-Things use on a common hospital device. This design showed high sensor accuracies and the ability to use data in real-time applications, showing promise in the ability to capture currently inaccessible clinical data. Further use of this device could facilitate improved research into the incentive spirometer to improve adoption, incentivize adherence, and investigate the clinical effectiveness to help guide clinical care.

17.
Sci Adv ; 9(22): eadg4346, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37256956

RESUMO

In aromatic systems with large π-conjugated structures, armchair and zigzag configurations can affect each material's electronic properties, determining their performance and generating certain quantum effects. Here, we explore the intrinsic effect of armchair and zigzag pathways on charge transport through single hexabenzocoronene molecules. Theoretical calculations and systematic experimental results from static carbon-based single-molecule junctions and dynamic scanning tunneling microscope break junctions show that charge carriers are preferentially transported along the hexabenzocoronene armchair pathway, and thus, the corresponding current through this pathway is approximately one order of magnitude higher than that through the zigzag pathway. In addition, the molecule with the zigzag pathway has a smaller energy gap. In combination with its lower off-state conductance, it shows a better field-effect performance because of its higher on-off ratio in electrical measurements. This study on charge transport pathways offers a useful perspective for understanding the electronic properties of π-conjugated systems and realizing high-performance molecular nanocircuits toward practical applications.

18.
PNAS Nexus ; 2(11): pgad347, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38024421

RESUMO

Prior to the eventual arrival of carbon neutrality, solar-driven syngas production from methane steam reforming presents a promising approach to produce transportation fuels and chemicals. Simultaneous activation of the two reactants, i.e. methane and water, with notable geometric and polar discrepancy is at the crux of this important subject yet greatly challenging. This work explores an exceptional semiconducting hybrid of RhOx/GaN@InGaN nanowires for overcoming this critical challenge to achieve efficient syngas generation from methane steam reforming by photocatalysis. By coordinating density functional theoretical calculations and microscopic characterizations, with in situ spectroscopic measurements, it is found that the multifunctional RhOx/GaN interface is effective for simultaneously activating both CH4 and H2O by stretching the C-H and O-H bonds because of its unique Lewis acid/base attribute. With the aid of energetic charge carriers, the stretched C-H and O-H bonds of reactants are favorably cleaved, resulting in the key intermediates, i.e. *CH3, *OH, and *H, to sit on Rh sites, Rh sites, and N sites, respectively. Syngas is subsequently produced via energetically favored pathway without additional energy inputs except for light. As a result, a benchmarking syngas formation rate of 8.1 mol·gcat-1·h-1 is achieved with varied H2/CO ratios from 2.4 to 0.8 under concentrated light illumination of 6.3 W·cm-2, enabling the achievement of a superior turnover number of 10,493 mol syngas per mol Rh species over 300 min of long-term operation. This work presents a promising strategy for green syngas production from methane steam reforming by utilizing unlimited solar energy.

19.
Front Immunol ; 13: 1001598, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36311707

RESUMO

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disease that can lead to joint deformity and loss of function. Recent studies have shown great progress in the research of mesenchymal stem cells (MSCs) in RA. However, thus far, there have been no bibliometric or visualization analyses in this field. This bibliometric analysis provides a comprehensive overview of the general information and research hotspots of MSCs and RA. Methods: Articles relevant to MSCs and RA, published between 2012 and 2021, were searched using the Web of Science Core Collection database. Irrelevant publications were excluded from the analysis. Bibliometric and visualization analyses were conducted using VOSviewer, CiteSpace, and Scimago Graphica. Results: A total of 577 articles were analyzed. The annual number of publications increased from 2012 to 2017 and plateaued from 2017 to 2021. China and the USA had the largest number of publications. Collaboration among different organizations mainly occurs between institutes of the same country. Stem Cell Research and Therapy and Frontiers in Immunology were the most popular journals in this field. All the top 20 co-cited authors had a positive co-citation relationship. The top references indicate that MSCs can contribute to RA research and treatment mainly via immunomodulation. From 2012 to 2021, "collagen-induced arthritis," "immunomodulation," and "therapy" were some of the keywords associated with MSCs and RA, while "extracellular vesicles" showed a strong keyword burst from 2019 to 2021. Conclusion: MSCs and RA have been widely studied in different countries and institutions and by different authors over the last ten years. China and the USA had the largest number of publications. Different types of journals provide admirable sources for researchers. Some keywords, including immunomodulation and extracellular vesicles, may be hot spots in the near future. There will be more basic research and clinical translation of MSCs and RA, and substantial new treatments for RA will soon be developed.


Assuntos
Artrite Reumatoide , Células-Tronco Mesenquimais , Humanos , Artrite Reumatoide/tratamento farmacológico , Bibliometria , Bases de Dados Factuais
20.
Front Immunol ; 13: 995895, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389806

RESUMO

Sjögrens syndrome (SS) is caused by autoantibodies that attack proprioceptive salivary and lacrimal gland tissues. Damage to the glands leads to dry mouth and eyes and affects multiple systems and organs. In severe cases, SS is life-threatening because it can lead to interstitial lung disease, renal insufficiency, and lymphoma. Histological examination of the labial minor salivary glands of patients with SS reveals focal lymphocyte aggregation of T and B cells. More studies have been conducted on the role of B cells in the pathogenesis of SS, whereas the role of T cells has only recently attracted the attention of researchers. This review focusses on the role of various populations of T cells in the pathogenesis of SS and the progress made in research to therapeutically targeting T cells for the treatment of patients with SS.


Assuntos
Aparelho Lacrimal , Síndrome de Sjogren , Humanos , Síndrome de Sjogren/etiologia , Síndrome de Sjogren/terapia , Síndrome de Sjogren/diagnóstico , Linfócitos T/patologia , Glândulas Salivares Menores/patologia , Aparelho Lacrimal/patologia , Autoanticorpos
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