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1.
Plants (Basel) ; 13(12)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38931069

RESUMO

The holly Ilex dabieshanensis K. Yao & M. B. Deng, a tree endemic to the Dabieshan Mountains region in China, is a commonly used landscaping plant. Like other crops, its growth is affected by salt stress. The molecular mechanism underlying salt tolerance in holly is still unclear. In this study, we used NaCl treatment and RNA sequencing (RNA-seq) at different times to identify the salt stress response genes of holly. A total of 4775 differentially expressed genes (DEGs) were identified. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of the DEGs obtained at different salt treatment times (3, 6, 9, 12, and 24 h), as compared to control (ck, 0 h), showed that plant hormone signal transduction and carotenoid biosynthesis were highly enriched. The mechanism by which holly responds to salt stress involves many plant hormones, among which the accumulation of abscisic acid (ABA) and its signal transduction may play an important role. In addition, ion homeostasis, osmotic metabolism, accumulation of antioxidant enzymes and nonenzymatic antioxidant compounds, and transcription factors jointly regulate the physiological balance in holly, providing important guarantees for its growth and development under conditions of salt stress. These results lay the foundation for studying the molecular mechanisms of salt tolerance in holly and for the selection of salt-tolerant varieties.

2.
Transl Lung Cancer Res ; 13(5): 1150-1162, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38854939

RESUMO

Background: The occurrence of pulmonary adenocarcinoma coexisting with atypical carcinoid tumors is a rare phenomenon. The presence of EML4-ALK fusion in an atypical carcinoid component of a histologically mixed tumor is even more uncommon. Due to their infrequency, the origin and pathogenesis of these mixed tumors remain largely unknown. The advances of therapy development in such patients are still limited and there is no standard treatment. We present a case of collision tumor in the lung consisting of atypical carcinoid and adenocarcinoma to better understand the clinical characteristics of this disease. Case Description: We report an extremely rare case of EML4-ALK rearrangement in a pulmonary atypical carcinoid tumor that coexisting with adenocarcinoma. A 58-year-old woman, who was asymptomatic, underwent pulmonary lobectomy due to the detection of a gradually enlarging solitary pulmonary nodule in the right upper lung. Histological examination of the resected tumor revealed the presence of both atypical carcinoid (approximately 80%) and adenocarcinoma (approximately 20%) components. Metastases by the carcinoid component were observed in mediastinal lymph nodes (station 2R and 4R) and in the primary tumor. Anaplastic lymphoma kinase (ALK) rearrangement was detected in both the primary and metastatic lesions of the carcinoid tumor. Four cycles of chemotherapy with etoposide and carboplatin were dispensed after surgery. Conclusions: This is the first reported case of coexisting pulmonary adenocarcinoma and atypical carcinoid tumor with an ALK fusion only detected in the carcinoid component. The presence of ALK rearrangement in pulmonary carcinoid tumor is very uncommon, and there is currently no standard treatment for advanced stages. Therefore, comprehensive molecular testing, including ALK rearrangement analysis, should be recommended for mixed tumors exhibiting features of atypical carcinoid. ALK inhibitors could represent a potential treatment strategy for selected patients.

3.
ACS Appl Mater Interfaces ; 16(23): 29805-29822, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38830200

RESUMO

Periprosthetic osteolysis induced by the ultrahigh-molecular-weight polyethylene (UHMWPE) wear particles is a major complication associated with the sustained service of artificial joint prostheses and often necessitates revision surgery. Therefore, a smart implant with direct prevention and repair abilities is urgently developed to avoid painful revision surgery. Herein, we fabricate a phosphatidylserine- and polyethylenimine-engineered niobium carbide (Nb2C) MXenzyme-coated micro/nanostructured titanium implant (PPN@MNTi) that inhibits UHMWPE particle-induced periprosthetic osteolysis. The specific mechanism by which PPN@MNTi operates involves the bioresponsive release of nanosheets from the MNTi substrate within an osteolysis microenvironment, initiated by the cleavage of a thioketal-dopamine molecule sensitive to reactive oxygen species (ROS). Subsequently, functionalized Nb2C MXenzyme could target macrophages and escape from lysosomes, effectively scavenging intracellular ROS through its antioxidant nanozyme-mimicking activities. This further achieves the suppression of osteoclastogenesis by inhibiting NF-κB/MAPK and autophagy signaling pathways. Simultaneously, based on the synergistic effect of MXenzyme-integrated coatings and micro/nanostructured topography, the designed implant promotes the osteogenic differentiation of bone mesenchymal stem cells to regulate bone homeostasis, further achieving advanced osseointegration and alleviable periprosthetic osteolysis in vivo. This study provides a precise prevention and repair strategy of periprosthetic osteolysis, offering a paradigm for the development of smart orthopedic implants.


Assuntos
Nióbio , Osteogênese , Osteólise , Osteogênese/efeitos dos fármacos , Osteólise/patologia , Osteólise/prevenção & controle , Osteólise/metabolismo , Nióbio/química , Camundongos , Animais , Polietilenos/química , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Titânio/química , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo
4.
J Colloid Interface Sci ; 672: 401-414, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38850865

RESUMO

Crafting an inorganic semiconductor heterojunction with defect engineering and morphology modulation is a strategic approach to produce clean energy by the highly efficient light-driven splitting of water. In this paper, a novel Z-scheme sulfur-vacancy containing Zn3In2S6 (Vs-Zn3In2S6) nanosheets/In2O3 hollow hexagonal prisms heterostructrue (Vs-ZIS6INO) was firstly constructed by an oil bath method, in which Vs-Zn3In2S6 nanosheets grew on the surfaces of In2O3 hollow hexagonal prisms to form a hollow core-shell structure. The obtained Vs-ZIS6INO heterostructrue exhibited much enhanced activity of the production of H2 and H2O2 by the light-driven water splitting. In particular, under visible light irradiation (λ > 420 nm), the rate of generation of H2 of Vs-ZIS6INO sample containing 30 wt% Vs-Zn3In2S6 (30Vs-ZIS6INO) could reach 3721 µmol g-1h-1, which was 87 and 6 times higher than those of Zn3In2S6 (43 µmol g-1h-1) and Vs-Zn3In2S6 (586 µmol g-1h-1), respectively. Meanwhile, 30Vs-ZIS6INO could exhibit the rate of H2O2 production of 483 µmol g-1h-1 through the dual pathways of indirect 2e- oxygen reduction (ORR) and water oxidation (WOR) without adding any sacrifice agents, far exceeding In2O3 (7 µmol g-1h-1) and Vs-Zn3In2S6 (58 µmol g-1h-1). The excellent photocatalytic activities of H2 and H2O2 generations of Vs-ZIS6INO sample might result from the synergistic effect of the sulfur vacancy, hollow core-shell structure, and Z-scheme heterostructure, which accelerated the electron delocalization, enhanced the absorption and conversion of solar energy, reduced the carrier diffusion distance, and ensured high REDOX ability. In addition, the possible photocatalytic mechanisms for the production of H2 and H2O2 were discussed in detail. This study provided a new idea and reference for constructing the novel and efficient inorganic semiconductor heterostructures by coordinating vacancy defect and morphology design to adequately utilize water splitting for the production of clean energy.

5.
Sci Rep ; 14(1): 12709, 2024 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830938

RESUMO

To assess the efficacy of stent grafts (SGs) in managing central venous obstruction disease (CVOD) in hemodialysis (HD) patients with arteriovenous (AV) access, and to identify predictive factors influencing the SG treatment outcomes. HD subjects with CVOD who underwent SGs placement at our center between August 2018 and June 2022 were enrolled. Survival curve analysis using the Kaplan-Meier method and log-rank test was performed. Cox proportional hazards regression analysis was employed to identify predictive factors associated with outcomes. A total of 59 SG implantation procedures for CVOD were analyzed, comprising 30 cases of stenosis and 29 cases of occlusion. The access circuit primary patency (ACPP) at 6, 12, and 24 months post-SG placement were 80.9%, 53.8%, and 31.4%, respectively, while, the target lesion primary patency (TLPP) were 91.3%, 67.6%, and 44.5%, respectively. Subgroup analysis revealed higher TLPP in the stenosis group compared to the occlusion group, although the difference was not statistically significant (P = 0.165). The TLPP was significantly improved by SG placement in those who had antecedent balloon dilations (P < 0.001). Cox proportional hazards regression identified target lesion length ≥ 30 mm and procedure defects as independent predictors of lower TLPP after SG treatment for CVOD in HD patients. SG placement demonstrates safety and efficacy in managing CVOD among HD patients, leading to improved TLPP of endovascular therapy (EVT) for CVOD. Notably, long target lesions (≥ 30 mm) and procedure defects emerged as predictive factors influencing TLPP.


Assuntos
Falência Renal Crônica , Diálise Renal , Stents , Grau de Desobstrução Vascular , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Falência Renal Crônica/terapia , Falência Renal Crônica/complicações , Idoso , Resultado do Tratamento , Estudos Retrospectivos , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Constrição Patológica/cirurgia , Adulto , Estimativa de Kaplan-Meier , Modelos de Riscos Proporcionais , Oclusão de Enxerto Vascular/etiologia
6.
J Nanobiotechnology ; 22(1): 325, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858695

RESUMO

BACKGROUND: Osteoarthritis (OA) is an aging-related degenerative joint disorder marked by joint discomfort and rigidity. Senescent chondrocytes release pro-inflammatory cytokines and extracellular matrix-degrading proteins, creating an inflammatory microenvironment that hinders chondrogenesis and accelerates matrix degradation. Targeting of senescent chondrocytes may be a promising approach for the treatment of OA. Herein, we describe the engineering of an injectable peptide-hydrogel conjugating a stem cell-homing peptide PFSSTKT for carrying plasmid DNA-laden nanoparticles and Tanshinon IIA (pPNP + TIIA@PFS) that was designed to attenuate OA progression by improving the senescent microenvironment and fostering cartilage regeneration. RESULTS: Specifically, pPNP + TIIA@PFS elevates the concentration of the anti-aging protein Klotho and blocks the transmission of senescence signals to adjacent healthy chondrocytes, significantly mitigating chondrocyte senescence and enhancing cartilage integrity. Additionally, pPNP + TIIA@PFS recruit bone mesenchymal stem cells and directs their subsequent differentiation into chondrocytes, achieving satisfactory chondrogenesis. In surgically induced OA model rats, the application of pPNP + TIIA@PFS results in reduced osteophyte formation and attenuation of articular cartilage degeneration. CONCLUSIONS: Overall, this study introduces a novel approach for the alleviation of OA progression, offering a foundation for potential clinical translation in OA therapy.


Assuntos
Condrócitos , Condrogênese , Glucuronidase , Hidrogéis , Proteínas Klotho , Células-Tronco Mesenquimais , Osteoartrite , Plasmídeos , Ratos Sprague-Dawley , Animais , Osteoartrite/terapia , Osteoartrite/tratamento farmacológico , Hidrogéis/química , Ratos , Condrócitos/metabolismo , Condrócitos/efeitos dos fármacos , Glucuronidase/metabolismo , Glucuronidase/farmacologia , Condrogênese/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Masculino , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/metabolismo , Progressão da Doença , Nanopartículas/química , Humanos , DNA , Senescência Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos
7.
J Colloid Interface Sci ; 672: 75-85, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38833736

RESUMO

Carbon dioxide (CO2) electroreduction provides a sustainable route for realizing carbon neutrality and energy supply. Up to now, challenges remain in employing abundant and inexpensive nickel materials as candidates for CO2 reduction due to their low activity and favorable hydrogen evolution. Here, the representative iron-modified nickel nanoparticles embedded in nitrogen-doped carbon (Ni1-Fe0.125-NC) with the porous botryoid morphology were successfully developed. Hexamethylenetetramine is used as nitrogen-doped carbon source. The collaboration of internal lattice expansion with electron effect and external confinement effect with size effect endows the significant enhancement in electrocatalytic CO2 reduction. The optimized Ni1-Fe0.125-NC exhibits broad potential ranges for continuous carbon monoxide (CO) production. A superb CO Faradaic efficiency (FECO) of 85.0 % realized at -1.1 V maintains a longtime durability over 35 h, which exceeds many state-of-the-art metal catalysts. Theoretical calculations further confirm that electron redistribution promotes the desorption of CO in the process for favorable CO production. This work opens a new avenue to design efficient nickel-based materials by considering the intrinsic structure and external confinement for CO2 reduction.

8.
Bioact Mater ; 38: 137-153, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38699244

RESUMO

Enhancing the regeneration of cartilage defects remains challenging owing to limited innate self-healing as well as acute inflammation arising from the overexpression of reactive oxygen species (ROS) in post-traumatic microenvironments. Recently, stem cell-derived exosomes (Exos) have been developed as potential cell-free therapy for cartilage regeneration. Although this approach promotes chondrogenesis, it neglects the emerging inflammatory microenvironment. In this study, a smart bilayer-hydrogel dual-loaded with sodium diclofenac (DC), an anti-inflammatory drug, and Exos from bone marrow-derived mesenchymal stem cells was developed to mitigate initial-stage inflammation and promote late-stage stem-cell recruitment and chondrogenic differentiation. First, the upper-hydrogel composed of phenylboronic-acid-crosslinked polyvinyl alcohol degrades in response to elevated levels of ROS to release DC, which mitigates oxidative stress, thus reprogramming macrophages to the pro-healing state. Subsequently, Exos are slowly released from the lower-hydrogel composed of hyaluronic acid into an optimal microenvironment for the stimulation of chondrogenesis. Both in vitro and in vivo assays confirmed that the dual-loaded bilayer-hydrogel reduced post-traumatic inflammation and enhanced cartilage regeneration by effectively scavenging ROS and reprogramming macrophages. The proposed platform provides multi-staged therapy, which allows for the optimal harnessing of Exos as a therapeutic for cartilage regeneration.

9.
Sci Transl Med ; 16(741): eadj5705, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38569015

RESUMO

Cancer-associated fibroblasts (CAFs) are abundant stromal cells in the tumor microenvironment that promote cancer progression and relapse. However, the heterogeneity and regulatory roles of CAFs underlying chemoresistance remain largely unclear. Here, we performed a single-cell analysis using high-dimensional flow cytometry analysis and identified a distinct senescence-like tetraspanin-8 (TSPAN8)+ myofibroblastic CAF (myCAF) subset, which is correlated with therapeutic resistance and poor survival in multiple cohorts of patients with breast cancer (BC). TSPAN8+ myCAFs potentiate the stemness of the surrounding BC cells through secretion of senescence-associated secretory phenotype (SASP)-related factors IL-6 and IL-8 to counteract chemotherapy. NAD-dependent protein deacetylase sirtuin 6 (SIRT6) reduction was responsible for the senescence-like phenotype and tumor-promoting role of TSPAN8+ myCAFs. Mechanistically, TSPAN8 promoted the phosphorylation of ubiquitin E3 ligase retinoblastoma binding protein 6 (RBBP6) at Ser772 by recruiting MAPK11, thereby inducing SIRT6 protein destruction. In turn, SIRT6 down-regulation up-regulated GLS1 and PYCR1, which caused TSPAN8+ myCAFs to secrete aspartate and proline, and therefore proved a nutritional niche to support BC outgrowth. By demonstrating that TSPAN8+SIRT6low myCAFs were tightly associated with unfavorable disease outcomes, we proposed that the combined regimen of anti-TSPAN8 antibody and SIRT6 activator MDL-800 is a promising approach to overcome chemoresistance. These findings highlight that senescence contributes to CAF heterogeneity and chemoresistance and suggest that targeting TSPAN8+ myCAFs is a promising approach to circumvent chemoresistance.


Assuntos
Neoplasias da Mama , Fibroblastos Associados a Câncer , Sirtuínas , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Resistencia a Medicamentos Antineoplásicos , Recidiva Local de Neoplasia/patologia , Fibroblastos/patologia , Microambiente Tumoral , Proteínas de Ligação a DNA , Ubiquitina-Proteína Ligases , Tetraspaninas/genética , Tetraspaninas/metabolismo
10.
Molecules ; 29(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38474624

RESUMO

Shut-in after fracturing is generally adopted for wells in shale oil reservoirs, and imbibition occurring in matrix nanopores has been proven as an effective way to improve recovery. In this research, a molecular dynamics (MD) simulation was used to investigate the effects of wettability and pressure on nanopore imbibition during shut-in for a typical shale reservoir, Jimsar. The results indicate that the microscopic advancement mechanism of the imbibition front is the competitive adsorption between "interfacial water molecules" at the imbibition front and "adsorbed oil molecules" on the pore wall. The essence of spontaneous imbibition involves the adsorption and aggregation of water molecules onto the hydroxyl groups on the pore wall. The flow characteristics of shale oil suggest that the overall push of the injected water to the oil phase is the main reason for the displacement of adsorbed oil molecules. Thus, shale oil, especially the heavy hydrocarbon component in the adsorbed layer, tends to slip on the walls. However, the weak slip ability of heavy components on the wall surface is an important reason that restricts the displacement efficiency of shale oil during spontaneous imbibition. The effectiveness of spontaneous imbibition is strongly dependent on the hydrophilicity of the matrix pore's wall. The better hydrophilicity of the matrix pore wall facilitates higher levels of adsorption and accumulation of water molecules on the pore wall and requires less time for "interfacial water molecules" to compete with adsorbed oil molecules. During the forced imbibition process, the pressure difference acts on both the bulk oil and the boundary adsorption oil, but mainly on the bulk oil, which leads to the occurrence of wetting hysteresis. Meanwhile, shale oil still existing in the pore always maintains a good, stratified adsorption structure. Because of the wetting hysteresis phenomenon, as the pressure difference increases, the imbibition effect gradually increases, but the actual capillary pressure gradually decreases and there is a loss in the imbibition velocity relative to the theoretical value. Simultaneously, the decline in hydrophilicity further weakens the synergistic effect on the imbibition of the pressure difference because of the more pronounced wetting hysteresis. Thus, selecting an appropriate well pressure enables cost savings and maximizes the utilization of the formation's natural power for enhanced oil recovery (EOR).

11.
ChemSusChem ; : e202400189, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38504639

RESUMO

Due to the larger sizes and stronger positive polarity of Zn2+ than dominant univalent ions, Zn2+ sluggish diffusion within V2O5 host electrodes is an essential issue in developing aqueous zinc-ion batteries (ZIBs) of higher energy densities. Herein, a high-performance V2O5 cathode was developed through subtly synthesizing and tuning V2O5 with oxygen vacancies-enriched and elongated apical V=O1 bond by altering the gradient concentration of hydrazine hydrate in the gas-solid reaction system. This strategy can enhance both intrinsic and extrinsic conductivity to a large extent. The electrochemical testing demonstrated the oxygen vacancies-enriched and elongated apical V=O1 bond can not only increase the intrinsic electronic conductivity of V2O5, but also induce additional pseudocapacitance to enhance the Zn2+ diffusion kinetics. We used infrared spectroscopy and Raman spectroscopy to characterize the change in the bond length structure of V2O5. Simultaneously, the long-term cyclability (capacity retention of 76.9 % after 1200 cycles at 4.0 A g-1) and rate capabilities (218 mAh g-1 at 4.0 A g-1) are promoted as well. We believe that our work might shed light on the bond length engineering of V2O5 and provide insights for the reasonable designing of novel cathodes for practical rechargeable ZIBs.

12.
J Environ Manage ; 356: 120592, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38508009

RESUMO

Chicken manure (CM) can pose a serious threat to environmental and human health, and need to be managed properly. The compost can effectively treat CM. However, there is limited research on the heavy metals and antibiotic resistance genes (ARGs) during compost CM. In this study, the combined application of reactor and static composting (RSC) was used to produce organic fertilizer of CM (OCM), and heavy metals, ARGs and bacterial community structure was investigated. The results show that RSC could be used to produce OCM, and OCM meet the National organic fertilizer standard (NY/T525-2021). Compared to the initial CM, DTPA-Cu, DTPA-Zn, DTPA-Pb, DTPA-Cr, DTPA-Ni and DTPA-As in OCM decreased by 40.83%, 23.73%, 34.27%, 38.62%, 16.26%, and 43.35%, respectively. RSC decreased the relative abundance of ARGs in CM by 84.06%, while the relative abundance of sul1 and ermC increased. In addition, the relative abundance and diversity of ARGs were mainly influenced by the bacterial community, with Actinobacteria, Firmicutes, and Proteobacteria becoming the dominant phyla during composting, and probably being the main carriers and dispersers of most of the ARGs. Network analyses confirmed that Gracilibacillus, Lactobacillus, Nocardiopsis, Mesorhizobium and Salinicoccus were the main potential hosts of ARGs, with the main potential hosts of sul1 and ermC being Mesorhizobium and Salinicoccus. The passivation and physicochemical properties of heavy metals contribute to the removal of ARGs, with sul1 and ermC being affected by the toal heavy metals. Application of RSC allows CM to produce mature, safe organic fertilizer after 32 d and reduces the risk of rebound from ARGs, but the issues of sul1 and ermC gene removal cannot be ignored.


Assuntos
Compostagem , Metais Pesados , Animais , Humanos , Genes Bacterianos , Esterco/análise , Galinhas , Antibacterianos/farmacologia , Fertilizantes , Resistência Microbiana a Medicamentos/genética , Bactérias/genética , Metais Pesados/análise , Ácido Pentético
13.
Front Immunol ; 15: 1293883, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38455057

RESUMO

Fibrotic diseases, such as idiopathic pulmonary fibrosis (IPF) and systemic scleroderma (SSc), are commonly associated with high morbidity and mortality, thereby representing a significant unmet medical need. Interleukin 11 (IL11)-mediated cell activation has been identified as a central mechanism for promoting fibrosis downstream of TGFß. IL11 signaling has recently been reported to promote fibroblast-to-myofibroblast transition, thus leading to various pro-fibrotic phenotypic changes. We confirmed increased mRNA expression of IL11 and IL11Rα in fibrotic diseases by OMICs approaches and in situ hybridization. However, the vital role of IL11 as a driver for fibrosis was not recapitulated. While induction of IL11 secretion was observed downstream of TGFß signaling in human lung fibroblasts and epithelial cells, the cellular responses induced by IL11 was quantitatively and qualitatively inferior to that of TGFß at the transcriptional and translational levels. IL11 blocking antibodies inhibited IL11Rα-proximal STAT3 activation but failed to block TGFß-induced profibrotic signals. In summary, our results challenge the concept of IL11 blockade as a strategy for providing transformative treatment for fibrosis.


Assuntos
Interleucina-11 , Fator de Crescimento Transformador beta , Humanos , Fator de Crescimento Transformador beta/metabolismo , Transdução de Sinais , Fibrose , Miofibroblastos/metabolismo
14.
Nanomaterials (Basel) ; 14(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38334589

RESUMO

Methanol steam reforming (MSR) is studied on a Pt3Sn surface using the density functional theory (DFT). An MSR network is mapped out, including several reaction pathways. The main pathway proposed is CH3OH + OH → CH3O → CH2O → CH2O + OH → CH2OOH → CHOOH → COOH → COOH + OH → CO2 + H2O. The adsorption strengths of CH3OH, CH2O, CHOOH, H2O and CO2 are relatively weak, while other intermediates are strongly adsorbed on Pt3Sn(111). H2O decomposition to OH is the rate-determining step on Pt3Sn(111). The promotion effect of the OH group is remarkable on the conversions of CH3OH, CH2O and trans-COOH. In particular, the activation barriers of the O-H bond cleavage (e.g., CH3OH → CH3O and trans-COOH → CO2) decrease substantially by ~1 eV because of the involvement of OH. Compared with the case of MSR on Pt(111), the generation of OH from H2O decomposition is more competitive on Pt3Sn(111), and the presence of abundant OH facilitates the combination of CO with OH to generate COOH, which accounts for the improved CO tolerance of the PtSn alloy over pure Pt.

15.
Medicine (Baltimore) ; 103(5): e37136, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38306557

RESUMO

RATIONALE: Bilateral thalamic glioma is extremely rare and characterized by strictly limited involvement of bilateral thalami. To investigate its clinical and neuroimaging features, we herein reported a rare case of anaplastic astrocytoma (AA) involving both thalami and the brainstem and reviewed the literature. PATIENT CONCERNS: A-33-year-old Chinese woman was referred to our department owing to persistent headache and nausea and vomiting. Neurological examination showed mild cognitive impairment and positive Kernig sign. DIAGNOSIS: Brain magnetic resonance imaging (MRI) demonstrated asymmetrical and swollen lesions involving both thalami, midbrain and pontine tegmentum, without restricted diffusion or enhancement. On day 7 after admission, she was transferred to the department of neurosurgery and underwent a stereotactic brain biopsy of the right thalamic lesion. Histopathological features and immunohistochemistry were consistent with AA, IDH wild-type, World Health Organization grade III. INTERVENTIONS: She was administrated with mannitol and glycerin fructose for decreasing intracranial pressure. OUTCOMES: In spite of receiving chemotherapy, she died on 2-month after her initial diagnosis. LESSONS: AA involving in both thalami and brainstem is a rare entity with poor prognosis. The clinicians and radiologists should deepen their awareness of the specific MRI feature of bilateral thalamic involvement. When MRI alone is insufficient, the utility of stereotactic biopsy is essential for making a definitive diagnosis.


Assuntos
Astrocitoma , Neoplasias do Tronco Encefálico , Glioma , Humanos , Feminino , Astrocitoma/patologia , Glioma/patologia , Neoplasias do Tronco Encefálico/diagnóstico por imagem , Imageamento por Ressonância Magnética , Mesencéfalo/patologia
16.
BMC Med Educ ; 24(1): 191, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38403582

RESUMO

BACKGROUND: The global outbreak of coronavirus disease (COVID-19) has led medical universities in China to conduct online teaching. This study aimed to assess the effectiveness of a blended learning approach that combines online teaching and virtual reality technology in dental education and to evaluate the acceptance of the blended learning approach among dental teachers and students. METHODS: The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist was followed in this study. A total of 157 students' perspectives on online and virtual reality technology education and 54 teachers' opinions on online teaching were collected via questionnaires. Additionally, 101 students in the 2015-year group received the traditional teaching method (TT group), while 97 students in the 2017-year group received blended learning combining online teaching and virtual reality technology (BL group). The graduation examination results of students in the two groups were compared. RESULTS: The questionnaire results showed that most students were satisfied with the online course and the virtual simulation platform teaching, while teachers held conservative and neutral attitudes toward online teaching. Although the theoretical score of the BL group on the final exam was greater than that of the TT group, there was no significant difference between the two groups (P = 0.805). The skill operation score of the BL group on the final exam was significantly lower than that of the TT group (P = 0.004). The overall score of the BL group was lower than that of the TT group (P = 0.018), but the difference was not statistically significant (P = 0.112). CONCLUSIONS: The blended learning approach combining online teaching and virtual reality technology plays a positive role in students' learning and is useful and effective in dental education.


Assuntos
Educação a Distância , Humanos , Estudos Transversais , Educação a Distância/métodos , Aprendizagem , Avaliação Educacional/métodos , Educação em Odontologia/métodos
17.
ACS Sens ; 9(3): 1310-1320, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38390684

RESUMO

The sensitivity of chemiresistive gas sensors based on metal oxide semiconductors (MOSs) has been inherently affected by ambient humidity because their reactive oxygen species are easily hydroxylated by water molecules, which significantly reduces the accuracy of the gas sensors in food quality assessment. Although conventional metal organic frameworks (MOFs) can serve as coatings for MOSs for humidity-independent gas detection, they have to operate at high working temperatures due to their low or nonconductivity, resulting in high power consumption, significant manufacturing inconvenience, and short-term stability due to the oxidation of MOFs. Here, the conductive and thickness-controlled CuHHTP (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene)-coated Cu2O are developed by combining in situ etching and layer-by-layer liquid-phase growth method, which achieves humidity-independent detection of H2S at room temperature. The response to H2S only decreases by 2.6% below 75% relative humidity (RH), showing a 9.6-fold improvement than the bare Cu2O sensor, which is ascribed to the fact that the CuHHTP layer hinders the adsorption of water molecules. Finally, a portable alarm system is developed to monitor food quality by tracking released H2S. Compared with gas chromatography method, their relative error is within 9.4%, indicating a great potential for food quality assessment.


Assuntos
Sulfeto de Hidrogênio , Estruturas Metalorgânicas , Umidade , Qualidade dos Alimentos , Óxidos , Água
18.
Math Biosci Eng ; 21(1): 1342-1355, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303468

RESUMO

Extracting entity relations from unstructured Chinese electronic medical records is an important task in medical information extraction. However, Chinese electronic medical records mostly have document-level volumes, and existing models are either unable to handle long text sequences or exhibit poor performance. This paper proposes a neural network based on feature augmentation and cascade binary tagging framework. First, we utilize a pre-trained model to tokenize the original text and obtain word embedding vectors. Second, the word vectors are fed into the feature augmentation network and fused with the original features and position features. Finally, the cascade binary tagging decoder generates the results. In the current work, we built a Chinese document-level electronic medical record dataset named VSCMeD, which contains 595 real electronic medical records from vascular surgery patients. The experimental results show that the model achieves a precision of 87.82% and recall of 88.47%. It is also verified on another Chinese medical dataset CMeIE-V2 that the model achieves a precision of 54.51% and recall of 48.63%.


Assuntos
Registros Eletrônicos de Saúde , Redes Neurais de Computação , Humanos , Armazenamento e Recuperação da Informação , China
19.
Adv Mater ; 36(19): e2309231, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38345181

RESUMO

Dual-metal center catalysts (DMCs) have shown the ability to enhance the oxygen reduction reaction (ORR) owing to their distinctive structural configurations. However, the precise modulation of electronic structure and the in-depth understanding of synergistic mechanisms between dual metal sites of DMCs at the atomic level remain challenging. Herein, mimicking the ferredoxin, Fe-based DMCs (Fe2N6-S) are strategically designed and fabricated, in which additional Fe and S sites are synchronously installed near the Fe sites and serve as "dual modulators" for coarse- and fine-tuning of the electronic modulation, respectively. The as-prepared Fe2N6-S catalyst exhibits enhanced ORR activity and outstanding Zinc-air (Zn-air) battery performance compared to the conventional single Fe site catalysts. The theoretical and experimental results reveal that introducing the second metal Fe creates a dual adsorption site that alters the O2 adsorption configuration and effectively activates the O─O bond, while the synergistic effect of dual Fe sites results in the downward shift of the d-band center, facilitating the release of OH*. Additionally, local electronic engineering of heteroatom S for Fe sites further facilitates the formation of the rate-determining step OOH*, thus accelerating the reaction kinetics.

20.
Purinergic Signal ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421486

RESUMO

For many years, there has been ongoing research on the P2X7 receptor (P2X7R). A comprehensive, systematic, and objective evaluation of the scientific output and status of P2X7R will be instrumental in guiding future research directions. This study aims to present the status and trends of P2X7R research from 2002 to 2023. Publications related to P2X7R were retrieved from the Web of Science Core Collection database. Quantitative analysis and visualization tools were Microsoft Excel, VOSviewer, and CiteSpace software. The analysis content included publication trends, literature co-citation, and keywords. 3282 records were included in total, with the majority of papers published within the last 10 years. Based on literature co-citation and keyword analysis, neuroinflammation, neuropathic pain, gastrointestinal diseases, tumor microenvironment, rheumatoid arthritis, age-related macular degeneration, and P2X7R antagonists were considered to be the hotspots and frontiers of P2X7R research. Researchers will get a more intuitive understanding of the status and trends of P2X7R research from this study.

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