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1.
RSC Adv ; 14(24): 16912-16920, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38799222

RESUMO

In this study, polypropylene/halloysite nanotube (PP/HNT) composite separators were prepared by coating HNTs treated with hydrochloric acid (HCl) of different concentrations on both sides of a PP separator. The effect of HNTs treated with hydrochloric acid (HCl) of different concentrations on the properties of PP/HNT composite separators was investigated. The results indicate that the PP/HNT composite separator exhibits higher electrolyte uptake and wettability than a commercial PP separator, resulting in a better electrochemical performance in Li/LiFePO4 cells. In particular, the PP/HNTs-1.2 M composite separator with HNTs treated with 1.2 M HCl exhibits the highest electrolyte uptake (384%) and ionic conductivity (1.03 mS cm-1). The cells assembled with a PP/HNTs-1.2 M composite separator deliver discharge capacities of 166 mA h g-1 (0.5 C) and 131 mA h g-1 (3 C) with attractive cycling performance (87.6% capacity retention after 100 cycles). HNTs treated with HCl of appropriate concentrations can significantly improve the properties of PP/HNT composite separators for application in lithium-ion batteries.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 317: 124449, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38754206

RESUMO

To explore the intrinsic mechanism of pure organic room temperature and clustering-induced phosphorescence and investigate mechanochromism and structural-function relationships, here, 4-(2-(9H-carbazol-9-yl)phenyl)-2-amino-6-methoxypyridine-3,5-dicarbonitrile (Lo-CzAD), 4-(3-(9H-carbazol-9-yl)phenyl)-2-amino-6-methoxypyridine-3,5-dicarbonitrile (Lm-CzAD), and 4-(4-(9H-carbazol-9-yl)phenyl)-2-amino-6-methoxypyridine-3,5-dicarbonitrile (Lp-CzAD) were designed and synthesized by choosing self-made carbazole and 3, 5-dicyanopyridine (DCP) unit as electron acceptor and electron donor in sequence. Compared with crystals Lm-CzAD and Lp-CzAD, crystal Lo-CzAD shows better room temperature phosphorescence (RTP) performance, with RTP lifetimes of 187.16 ms, as well as afterglows 1s, which are attributed to twisted carbazole unit and donor-acceptor (D-A) molecular conformation, big crystal density and spin orbit coupling constant ξ (S1 â†’ T1 and S1 â†’ T2), as well as intermolecular H type stacking and small ξ (S0 â†’ T1). By choosing urea and PPh3 as host materials and tuning doping ratio, four doping systems were successfully constructed, significantly improving RTP performance of Lo-CzAD and Lp-CzAD, as well as showing different fluorescence and RTP. The lifetimes and afterglows of pure organic Urea/Lo-CzAD and Urea/Lp-CzAD systems are up to 478.42 ms, 5 s, 261.66 ms and 4.5 s in turn. Moreover, Lo-CzAD and Lp-CzAD show time-dependent RTP in doping systems due to monomer and aggregate dispersion, as well as clustering-induced phosphorescence. Based on the different luminescent properties, multiple information encryptions were successfully constructed.

3.
Cancer Cell Int ; 24(1): 167, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734676

RESUMO

BACKGROUND: Accumulating evidences indicate that the specific alternative splicing (AS) events are linked to the occurrence and prognosis of gastric cancer (GC). Nevertheless, the impact of AS is still unclear and needed to further elucidation. METHODS: The expression profile of GC and normal samples were downloaded from TCGA. AS events were achieved from SpliceSeq database. Cox regression together with LASSO analysis were employed to identify survival-associated AS events (SASEs) and calculate risk scores. PPI and pathway enrichment analysis were implemented to determine the function and pathways of these genes. Kaplan-Meier (K-M) analysis and Receiver Operating Characteristic Curves were used to evaluate the clinical significance of genes of SASEs. Q-PCR were applied to validate the hub genes on the survival prognosis in 47 GC samples. Drug sensitivity and immune cell infiltration analysis were conducted. RESULTS: In total, 48 140 AS events in 10 610 genes from 361 GC and 31 normal samples were analyzed. Through univariate Cox regression, 855 SASEs in 763 genes were screened out. Further, these SASEs were analyzed by PPI and 17 hub genes were identified. Meanwhile, using Lasso and multivariate Cox regression analysis, 135 SASEs in 132 genes related to 7 AS forms were further screened and a GC prognostic model was constructed. K-M curves indicates that high-risk group has poorer prognosis. And the nomogram analysis on the basis of the multivariate Cox analysis was disclosed the interrelationships between 7 AS forms and clinical parameters in the model. Five key genes were then screened out by PPI analysis and Differential Expression Gene analysis based on TCGA and Combined-dataset, namely STAT3, RAD51B, SOCS2, POLE2 and TSR1. The expression levels of AS in STAT3, RAD51B, SOCS2, POLE2 and TSR1 were all significantly correlated with survival by qPCR verification. Nineteen drugs were sensitized to high-risk patients and eight immune cells showed significantly different infiltration between the STAD and normal groups. CONCLUSIONS: In this research, the prognostic model constructed by SASEs can be applied to predict the prognosis of GC patients and the selected key genes are expected to become new biomarkers and therapeutical targets for GC treatment.

4.
Carbohydr Polym ; 335: 121920, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38616070

RESUMO

Natural polymer-based hydrogels have been wildly used in electronic skin, health monitoring and human motion sensing. However, the construction of hydrogel with excellent mechanical strength and electrical conductivity totally using natural polymers still faces many challenges. In this paper, gelatin and oxidized sodium carboxymethylcellulose were used to synthesize a double-network hydrogel through the dynamic Schiff base bonds. Then, the mechanical strength of the hydrogel was further enhanced by immersing it in an ammonium sulfate solution based on the Hofmeister effect between gelatin and salt. Finally, the gelatin/oxidized sodium carboxymethylcellulose hydrogel exhibited high tensile properties (614 %), tensile fracture strength (2.6 MPa), excellent compressive fracture strength (64 MPa), and compressive toughness (4.28 MJ/m3). Also, the electrical conductivity reached 3.94 S/m. The hydrogel after salt soaked was fabricated as strain sensors, which could accurately monitor the movement of many joints in the human body, such as fingers, wrists, elbows, neck, and throat. Therefore, the designed hydrogel fully originated from natural polymers and has great application potential in motion detection and information recording.

5.
Int Immunopharmacol ; 132: 111998, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38593510

RESUMO

BACKGROUND: Given the intricate molecular complexities and heterogeneity inherent in T-cell immunotherapy of gastric cancer (GC), elucidative T-cell-related biomarkers were imperative needed for facilitating the prediction of GC patient prognosis and identify potential synergistic therapeutic targets. METHODS: We conducted COX regression analysis in TISIDB, TCGA-STAD, and GEO databases to identify 19 GC T-cell-mediated sensitivity tumor killing (TTK) genes (key GCTTKs). Based on key GCTTKs, we constructed two TTK patterns and analyzed their metabolic pathways, mutation features, clinical data distribution, immune cell infiltration, and prognosis. LASSO regression was performed to develop a T-cell-mediated GC Prognosis (TGCP) model. We validated the TGCP model in GC patients. TAP1 was further selected for investigation of its biological functions and molecular mechanisms. We assessed the potential of TAP1 as a promising therapeutic target for GC using Patient-derived organoids (PDOs)-derived xenografts (PDOXs) models of GC. RESULTS: The TTK patterns display notable disparities. The TGCP model showcases its proficiency in predicting immune response efficacy, effectively distinguishes immunotherapy difference GC patients. Our findings find further confirmation in PDOX models, affirming TAP1 can enhance immunotherapy facilitated by PDL1 inhibitors. Furthermore, Oxaliplatin, by promoting TAP1 expression, augments PDL1 expression, thereby enhancing the efficacy of immunotherapy. CONCLUSIONS: We constructed a TGCP model, which demonstrates satisfactory predictive accuracy. Out of 9 prognostic genes, TAP1 was validated as a synergistic target for Oxaliplatin and PDL1 inhibitors, offering a genetic-level explanation for the synergy observed in GC treatment involving Oxaliplatin in combination with PDL1 inhibitors.


Assuntos
Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Imunoterapia , Oxaliplatina , Neoplasias Gástricas , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/terapia , Neoplasias Gástricas/genética , Humanos , Animais , Oxaliplatina/farmacologia , Oxaliplatina/uso terapêutico , Imunoterapia/métodos , Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética , Camundongos , Linfócitos T/imunologia , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Sinergismo Farmacológico , Prognóstico
6.
Biochem Pharmacol ; 222: 116120, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38461905

RESUMO

The role of the Immunoglobulin Superfamily (IgSF) as adhesion molecules in orchestrating inflammation is pivotal, yet its specific involvement in gastric cancer (GC) remains unknown. We analyzed IgSF components and discerned conspicuously elevated VCAM1 expression in GC, correlating with a poor prognosis. Remarkably, VCAM1 enhances GC cell proliferation and migration by activating AKT-mTOR signaling. Moreover, lactate in the tumor microenvironment (TME) promotes dynamic lactylation of H3K18 (H3K18la), leading to transcriptional activation of VCAM1 in GC cells. Furthermore, VCAM1 actively mediates intercellular communication in the TME. AKT-mTOR-mediated CXCL1 expression is increased by VCAM1, facilitating the recruitment of human GC-derived mesenchymal stem cells (hGC-MSCs), thereby fostering immunesuppression and accelerating cancer progression. In summary, H3K18 lactylation upregulated VCAM1 transcription, which activated AKT-mTOR signaling, and promoted tumor cell proliferation, EMT Transition and tumor metastasis. VCAM1 upregulated CXCL1 expression by AKT-mTOR pathway, so as to facilitate hGC-MSCs and M2 macrophage recruitment and infiltration. These findings provide novel therapeutic targets for GC.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Movimento Celular , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Transição Epitelial-Mesenquimal , Microambiente Tumoral , Quimiocina CXCL1/metabolismo
7.
Angew Chem Int Ed Engl ; 62(50): e202314999, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37889729

RESUMO

The activation of molecular hydrogen is a key process in catalysis. Here, we demonstrate how polyoxometalate (POM)-based heterogeneous compounds functionalized with Platinum particles activate H2 by synergism between a hydrogen spillover mechanism and electron-proton transfer by the POM. This interplay facilitates the selective catalytic reduction of olefins and nitroarenes with high functional group tolerance. A family of polyoxotungstates covalently functionalized with boronic acids is reported. In the solid-state, the compounds are held together by non-covalent interactions (π-π stacking and hydrogen bonding). The resulting heterogeneous nanoscale particles form stable colloidal dispersions in acetonitrile and can be surface-functionalized with platinum nanoparticles by in situ photoreduction. The resulting materials show excellent catalytic activity in hydrogenation of olefins and nitrobenzene derivatives under mild conditions (1 bar H2 and room temperature).

8.
J Org Chem ; 88(14): 10257-10265, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37400425

RESUMO

Different chemoselectivities of phenols and thiophenols were observed in a Tf2O-promoted C3 functionalization of simple anthranils. The reaction of phenols and anthranils gives 3-aryl anthranils via a C-C bond formation, whereas thiophenols afford 3-thio anthranils through a C-S bond formation. Both reactions have a broad substrate scope and tolerate a wide range of functional groups, affording the corresponding products with specific chemoselectivity.

9.
Gastric Cancer ; 26(4): 565-579, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37062785

RESUMO

BACKGROUND: Gastric cancer (GC) is a cancer of the gastrointestinal tract that is highly malignant and has poor prognosis. Circular RNAs are a class of nonclassical RNA molecules that have been determined to be involved in GC malignancy in various ways. However, the underlying function and mechanism of circTDRD3 in gastric cancer remain largely unknown. METHODS: We analyzed circTDRD3 expression in databases and verified the findings in GC cell lines and tissue specimens. A series of functional gene overexpression and knockdown assays in vivo and in vitro were carried out to investigate the role of circTDRD3 in proliferation and metastasis. Here, we revealed the role of the miR-891b/ITGA2 axis by analyzing bioinformatics datasets. Furthermore, we performed dual-luciferase, fluorescence in situ hybridization, RNA pull-down, and functional rescue experiments to examine the relationships between circTDRD3 and its interacting molecules. Western blot confirmed the positive regulatory role of circTDRD3 in the AKT signaling pathway. A promoting effect of ATF4 on circTDRD3 was determined through chromatin immunoprecipitation. RESULTS: CircTDRD3 was significantly overexpressed in GC tissues compared with adjacent benign tissue, and its expression level was positively correlated with tumor volume and lymph node metastasis. CircTDRD3 promoted GC cell proliferation and migration in vitro and in vivo. Mechanistically, circTDRD3 exerted a tumor-promoting effect by regulating the miR-891b/ITGA2 axis and AKT signaling pathway in a positive feedback manner mediated by the transcription factor ATF4. CONCLUSIONS: ATF4-mediated circTDRD3 overexpression modulates the proliferation and metastasis of GC cells through the miR-891b/ITGA2 axis in a positive feedback manner.


Assuntos
MicroRNAs , Neoplasias Gástricas , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Gástricas/patologia , Hibridização in Situ Fluorescente , Transdução de Sinais , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo
10.
Stem Cells Int ; 2023: 7072700, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37035447

RESUMO

Type II alveolar epithelial cell (AECII) apoptosis is one of the most vital causes of sepsis-induced acute respiratory distress syndrome (ARDS). Recent evidence has proved that bone mesenchymal stem cell-derived exosomes (BMSC-exos) can effectively reduce sepsis-induced ARDS. However, the function and molecular mechanism of BMSC-exos in sepsis-induced AECII apoptosis remain to be elucidated. In the present study, a more significant number of AECII apoptosis, high mitochondrial fission p-Drp1 protein levels, and low levels of mitochondrial biogenesis-related PGC1α, Tfam, and Nrf1 proteins accompanied with ATP content depression were confirmed in AECIIs in response to sepsis. Surprisingly, BMSC-exos successfully recovered mitochondrial biogenesis, including the upregulated expression of PGC1α, Tfam, Nrf1 proteins, and ATP contents, and prohibited p-Drp1-mediated mitochondrial fission by promoting Nrf2 expression. However, the aforementioned BMSC-exo reversal of mitochondrial dysfunction in AECIIs can be blocked by Nrf2 inhibitor ML385. Finally, BMSC-exos ameliorated the mortality rate, AECII apoptosis, inflammatory cytokine storm including HMGB1 and IL-6, and pathological lung damage in sepsis mice, which also could be prevented by ML385. These findings reveal a new mechanism of BMSC-exos in reversing mitochondrial dysfunction to alleviate AECII apoptosis, which may provide novel strategies for preventing and treating sepsis-induced ARDS.

11.
RSC Adv ; 13(10): 6606-6618, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36845586

RESUMO

Hierarchical hollow tubular porous carbons have been widely used in applications of supercapacitors, batteries, CO2 capture and catalysis due to their hollow tubular morphology, large aspect ratio, abundant pore structure and superior conductivity. Herein, hierarchical hollow tubular fibrous brucite-templated carbons (AHTFBCs) were prepared using natural mineral fiber brucite as the template and KOH as the chemical activator. The effects of different KOH additions on the pore structure and capacitive performance of AHTFBCs were systematically studied. The specific surface area and micropore content of AHTFBCs after KOH activation were higher than those of HTFBC. The specific surface area of the HTFBC is 400 m2 g-1, while the activated AHTFBC5 has a specific surface area of up to 625 m2 g-1. In particular, compared with HTFBC (6.1%), a series of AHTFBCs (22.1% for AHTFBC2, 23.9% for AHTFBC3, 26.8% for AHTFBC4 and 22.9% for AHTFBC5) with significantly increased micropore content were prepared by controlling the amount of KOH added. The AHTFBC4 electrode displays a high capacitance of 197 F g-1 at 1 A g-1 and the capacitance retention of 100% after 10 000 cycles at 5 A g-1 in the three-electrode system. And an AHTFBC4//AHTFBC4 symmetric supercapacitor exhibits the capacitance of 109 F g-1 at 1 A g-1 in 6 M KOH and an energy density of 5.8 W h kg-1 at 199.0 W kg-1 in 1 M Na2SO4 electrolyte. In addition, the capacity retention of AHTFBC4 in the symmetric supercapacitor was maintained at 92% after 5000 cycles in both 6 M KOH and 1 M Na2SO4 electrolytes.

12.
Chem Commun (Camb) ; 59(14): 1889-1906, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36661267

RESUMO

Recent progress on catalytic nitrene transfer reactions with hydroxylamine derivatives as prevalent precursors is summarized in this highlight. The salient features of these N-O derived nitrene transfer reagents are that they are readily available, bench-stable, and can be facilely activated by a range of transition metal-catalysts under mild conditions. The application of these reagents in transition metal-catalysis has led to many new amidation or amination reactions, such as C-H insertions and aziridination of olefins. These reagents have also been applied in difunctionalisation of unsaturated bonds, dearomative amination of indoles, and formation of N-X bonds. Moreover, the recent achievements in photocatalysis and enzyme catalysis further emphasize the importance of these appealing reagents. This highlight provides an overview of these reactions reported in recent years. Challenges and potential opportunities for future developments are also discussed.

13.
Chemistry ; 29(13): e202203220, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36458818

RESUMO

The design of efficient and stable oxygen evolution reaction (OER) catalysts based on noble-metal-free materials is crucial for energy conversion and storage. In this work, it was demonstrated how polyoxometalate (POM)-doped ZIF-67 can be converted into a stable oxygen evolution electrocatalyst by chemical etching, cation exchange, and thermal annealing steps. Characterization by X-ray photoelectron spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy and Raman spectroscopy indicate that POM-doped ZIF-67 derived carbon-supported metal oxides were synthesized. The resulting composite shows structural and compositional advantages which lead to low overpotential (306 mV at j=10 mA ⋅ cm-2 ) and long-term stability under harsh OER conditions (1.0 M aqueous KOH).

14.
Shock ; 58(6): 534-541, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36516451

RESUMO

ABSTRACT: Our previous study confirmed that cardiopulmonary bypass (CPB) leads to acute lung injury (ALI) via inducing high-mobility group box 1 (HMGB1) release. Recent research showed that HMGB1 promotes pulmonary injury mainly via exosomes transport. Currently, alveolar epithelial cell (AEC) necroptosis has been demonstrated to be involved in ALI. However, it is unknown whether exosomal inflammatory cytokine HMGB1 promotes ALI by inducing AEC necroptosis, and its underlying mechanisms remain elusive. Here, a prospective cohort study was carried out, in which plasma samples from 21 CPB patients were isolated at four specific time points: pre-CPB, 2, 12, and 24 h after initiation of CPB. Plasma exosomes were extracted via ultra-high-speed centrifugation and cocultured with AEC cell line-A549 cells at increasing concentrations of 50, 100, and 150 µg/mL. Then, HMGB1 antagonist-Box A and mtDNA deficiency ethidium bromide (EtBr) were applied to explore the underlying role of exosomal HMGB1 and cytoplasm mitochondrial DNA in AEC. Western blot analysis showed that plasma exosomal HMGB1 expression gradually increased and peaked at 24 h after CPB. Twenty-four-hour treatment of CPB-derived exosomes at 150 µg/mL for 24 h could induce necroptosis by promoting mitochondrial fission and further elevating cytoplasm mtDNA levels in A549 cells, which was successfully blocked by Box A or EtBr. Most importantly, EtBr significantly inhibited cytoplasm mtDNA downstream guanosine monophosphate (GMP)-AMP synthase (cGAS)/stimulator of interferon gene (STING) signal pathway. Collectively, these data demonstrate that CPB-derived plasma exosomal HMGB1 contributes to AEC necroptosis through the mtDNA/cGAS/STING pathway.


Assuntos
Lesão Pulmonar Aguda , Células Epiteliais Alveolares , Proteína HMGB1 , Necroptose , Humanos , Lesão Pulmonar Aguda/metabolismo , Células Epiteliais Alveolares/metabolismo , Ponte Cardiopulmonar/efeitos adversos , DNA Mitocondrial/metabolismo , Proteína HMGB1/metabolismo , Necroptose/genética , Nucleotidiltransferases/metabolismo , Estudos Prospectivos , Exossomos/metabolismo
15.
Opt Express ; 30(12): 21349-21361, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-36224856

RESUMO

Versatile applications have driven a desire for dual-band detection that enables seeing objects in multiple wavebands through a single photodetector. In this paper, a concept of using graphene/p-GaN Schottky heterojunction on top of a regular AlGaN-based p-i-n mesa photodiode is reported for achieving solar-/visible-blind dual-band (275 nm and 365 nm) ultraviolet photodetector with high performance. The highly transparent graphene in the front side and the polished sapphire substrate at the back side allows both top illumination and back illumination for the dual band detection. A system limit dark current of 1×10-9 A/cm2 at a negative bias voltage up to -10 V has been achieved, while the maximum detectivity obtained from the detection wavebands of interests at 275 nm and 365 nm are ∼ 9.0 ×1012 cm·Hz1/2/W at -7.5 V and ∼8.0 × 1011 cm·Hz1/2/W at +10 V, respectively. Interestingly, this new type of photodetector is dual-functional, capable of working as either photodiode or photoconductor, when switched by simply adjusting the regimes of bias voltage applied on the devices. By selecting proper bias, the device operation mode would switch between a high-speed photodiode and a high-gain photoconductor. The device exhibits a minimum rise time of ∼210 µs when working as a photodiode and a maximum responsivity of 300 A/W at 6 µW/cm2 when working as a photoconductor. This dual band and multi-functional design would greatly extend the utility of detectors based on nitrides.

16.
Tissue Eng Regen Med ; 19(5): 1001-1012, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35962859

RESUMO

BACKGROUND: Intervertebral disk (IVD) degeneration, which can cause lower back pain, is a major predisposing factor for disability and can be managed through multiple approaches. However, there is no satisfactory strategy currently available to reconstruct and recover the natural properties of IVDs after degeneration. As tissue engineering develops, scaffolds with embedded cell cultures have proved critical for the successful regeneration of IVDs. METHODS: In this study, an integrated scaffold for IVD replacement was developed. Through scanning electron microscopy and other mechanical measurements, we characterized the physical properties of different hydrogels. In addition, we simulated the physiological structure of natural IVDs. Nucleus pulposus (NP) cells and annulus fibrosus-derived stem cells (AFSCs) were seeded in gelatin methacrylate (GelMA) hydrogel at different concentrations to evaluate cell viability and matrix expression. RESULTS: It was found that different concentrations of GelMA hydrogel can provide a suitable environment for cell survival. However, hydrogels with different mechanical properties influence cell adhesion and extracellular matrix component type I collagen, type II collagen, and aggrecan expression. CONCLUSION: This tissue-engineered IVD implant had a similar structure and function as the native IVD, with the inner area mimicking the NP tissue and the outer area mimicking the stratified annulus fibrosus tissue. The new integrated scaffold demonstrated a good simulation of disc structure. The preparation of efficient and regeneration-promoting tissue-engineered scaffolds is an important issue that needs to be explored in the future. It is hoped that this work will provide new ideas and methods for the further construction of functional tissue replacement discs.


Assuntos
Produtos Biológicos , Disco Intervertebral , Agrecanas/metabolismo , Produtos Biológicos/metabolismo , Colágeno Tipo II/metabolismo , Gelatina , Hidrogéis/química , Disco Intervertebral/metabolismo , Metacrilatos/metabolismo , Engenharia Tecidual/métodos
17.
Chem Commun (Camb) ; 58(65): 9120-9123, 2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-35880715

RESUMO

A convenient Y(OTf)3-catalyzed cascade formal [4 + 2] cyclization approach for the formation of 1,4-benzoxazine scaffolds from benzoxazoles and propargyl alcohols through a ring-opening and regioselective ring-closure process has been developed. By using this mild and practical protocol, a broad range of aldehyde-containing 1,4-benzoxazine compounds were prepared in moderate to excellent yields with good functional group tolerance. Mechanistic studies indicated that an SN1 nucleophilic substitution of benzoxazole with a propargyl cation was involved in this transformation.


Assuntos
Benzoxazinas , Benzoxazóis , Catálise , Ciclização , Estrutura Molecular
18.
Biosensors (Basel) ; 12(5)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35624574

RESUMO

High sensitivity and reproducibility are highly desirable to a SERS sensor in diverse detection applications. Moreover, it is a great challenge to determine how to promote the target molecules to be more concentrated on the hotspots of the SERS substrate by engineering a surface with switching interfacial wettability. Along these lines, wafer-scale uniformly hydrophobic silicon nanorods arrays (SiNRs) decorated with Au nanoparticles were designed as the SERS substrate. Typically, the SERS substrate was fabricated by enforcing the polystyrene (PS) sphere self-assembly, as well as the plasma etching and the magnetron sputtering techniques. Consequently, the SERS substrate was treated by soaking within a n-dodecyl mercaptan (NDM) solution at different times in order to obtain adjustable wettabilities. By leveraging the electromagnetic enhancement resulted from the Au nanostructures and enrichment effect induced by the hydrophobicity, the SERS substrate is endowed with efficient SERS capabilities. During the detection of malachite green (MG), an ultralow relative standard deviation (RSD) 4.04-6.14% is achieved and the characteristic signal of 1172 cm-1 can be detected as low as 1 ng/mL. The proposed SiNRs' structure presents outstanding SERS activity with sensitivity and reproducibility rendering thus an ideal candidate for potential application in analytical detection fields.


Assuntos
Nanopartículas Metálicas , Nanotubos , Resíduos de Praguicidas , Ouro , Interações Hidrofóbicas e Hidrofílicas , Reprodutibilidade dos Testes , Silício
19.
Rev Sci Instrum ; 92(9): 094105, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598529

RESUMO

It is important to understand the changes in the characteristics of the brain network in the state of driving fatigue and to reveal the pattern of functional connectivity between brain regions when fatigue occurs. This paper proposes a method for the detection of driving fatigue based on electroencephalogram (EEG) signals using a phase lag index graph attention network (PLI-GAT). Phase synchronization between EEG signals is a key attribute for establishing communication links among different regions of the brain, and so, the PLI is used to construct a functional brain network reflecting the relationship between EEG signals from different channels. Multi-channel EEG time-frequency features are then modeled as graph data, and the driving fatigue monitoring model is trained using a GAT. Compared with traditional graph neural networks, the GAT applies an aggregation operation to adjacent EEG channel features through the attention mechanism. This enables the adaptive assignment of different neighbor weights, which greatly improves the expressiveness of the graph neural network model. The proposed method is validated on the publicly available SEED-VIG dataset, and the accuracy of fatigue state recognition is found to reach 85.53%. The results show that the functional connectivity among different channels is significantly enhanced in the fatigue state.


Assuntos
Condução de Veículo , Eletroencefalografia , Encéfalo , Fadiga , Humanos , Redes Neurais de Computação
20.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 35(3): 318-322, 2021 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-33719240

RESUMO

OBJECTIVE: To investigate and analyze the effectiveness of internal fixation with the two different cannulated screw implanting methods of rhomboid and inverted triangle in the treatment of femoral neck fracture in young adults. METHODS: The clinical data of 38 young adults with femoral neck fracture who met the selection criteria between January 2018 and August 2019 were retrospectively analyzed. According to the different methods of cannulated screw implanting, the patients were divided into two groups, 19 cases in each group. The trial group was treated with closed reduction and cannulated screw rhombic distribution internal fixation, while the control group was treated with closed reduction and cannulated screw inverted triangular distribution internal fixation. There was no significant differences in patients' gender, age, cause of injury, Garden classification of fracture, and time from injury to operation between the two groups ( P>0.05). The fracture healing time, the incidence of nonunion, femoral neck shortening, and femoral head necrosis were recorded and compared between the two groups; the effectiveness was evaluated by Harris score and visual analogue scale (VAS) score at last follow-up. RESULTS: The incisions of the two groups healed by first intention. All patients were followed up 12-24 months with an average of 15.5 months. There were 1 case of fracture nonunion and 2 cases of shortening of femoral neck in the trial group; while there were 2 cases of fracture nonunion, 1 case of necrosis of femoral head, and 6 cases of femoral neck shortening in the control group; the difference in the incidence of complications (15.8% vs. 47.4%) between the two groups was significant ( χ 2=4.385, P=0.036). The remaining 18 cases in the trial group and 17 cases in the control group all achieved osteonal union, and the healing time was (14.8±1.6) weeks and (15.9±1.3) weeks, respectively, showing no significant difference between the two groups ( t=1.265, P=0.214). At last follow-up, Harris score and VAS score of the trial group were 88.9±4.3 and 1.1±0.7, respectively, while those of the control group were 86.9±5.9 and 1.3±0.9, respectively, showing no significant difference ( t=0.603, P=0.550; t=1.152, P=0.257). Hip function was evaluated in accordance with Harris score, the results were excellent in 12 cases, good in 6 cases, and fair in 1 case in the trial group, the excellent and good rate was 94.74%; the results were excellent in 10 cases, good in 7 cases, and fair in 2 cases in the control group, the excellent and good rate was 89.47%; there was no significant difference in the excellent and good rate between the two groups ( χ 2=0.368, P=0.544). CONCLUSION: The short-term effectiveness of the two kinds of cannulated screw implanting methods is clear, rhomboid fixation of 4 screws has strong stability with stress distribution, which can effectively reduce the incidence of femoral neck shortening, fracture nonunion, femoral head necrosis, and other complications.


Assuntos
Fraturas do Colo Femoral , Parafusos Ósseos , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
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