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1.
Nature ; 615(7950): 62-66, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36859585

RESUMO

For capacitive energy storage at elevated temperatures1-4, dielectric polymers are required to integrate low electrical conduction with high thermal conductivity. The coexistence of these seemingly contradictory properties remains a persistent challenge for existing polymers. We describe here a class of ladderphane copolymers exhibiting more than one order of magnitude lower electrical conductivity than the existing polymers at high electric fields and elevated temperatures. Consequently, the ladderphane copolymer possesses a discharged energy density of 5.34 J cm-3 with a charge-discharge efficiency of 90% at 200 °C, outperforming the existing dielectric polymers and composites. The ladderphane copolymers self-assemble into highly ordered arrays by π-π stacking interactions5,6, thus giving rise to an intrinsic through-plane thermal conductivity of 1.96 ± 0.06 W m-1 K-1. The high thermal conductivity of the copolymer film permits efficient Joule heat dissipation and, accordingly, excellent cyclic stability at elevated temperatures and high electric fields. The demonstration of the breakdown self-healing ability of the copolymer further suggests the promise of the ladderphane structures for high-energy-density polymer capacitors operating under extreme conditions.

2.
J Biol Chem ; : 107499, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38944125

RESUMO

Blood amino acid levels are maintained in a narrow physiological range. The pancreatic α cells have emerged as the primary aminoacidemia regulator through glucagon secretion to promote hepatic amino acid catabolism. Interruption of glucagon signaling disrupts the liver - α cells axis leading to hyperaminoacidemia, which triggers a compensatory rise in glucagon secretion and α cell hyperplasia. The mechanisms of hyperaminoacidemia-induced α cell hyperplasia remain incompletely understood. Using a mouse α cell line and in vivo studies in zebrafish and mice, we found that hyperaminoacidemia-induced α cell hyperplasia requires ErbB3 signaling. In addition to mTORC1, another ErbB3 downstream effector STAT3 also plays a role in α cell hyperplasia. Mechanistically, ErbB3 may partner with ErbB2 to stimulate cyclin D2 and suppress p27 via mTORC1 and STAT3. Our study identifies ErbB3 as a new regulator for hyperaminoacidemia-induced α cell proliferation and a critical component of the liver-α cells axis that regulates aminoacidemia.

3.
Anal Chem ; 96(16): 6329-6336, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38597405

RESUMO

The simultaneous discrimination of multiple homologous sequences faces challenges due to the high similarity of sequences and the complexity of the discrimination system in most reported works. Herein, a simple and ingenious analysis method was developed to identify eight miRNAs of the let-7 family by combining logic gates and entropy-driven catalytic (EDC)-based lanthanide labeling inductively coupled plasma mass spectrometry (ICP-MS) technology. Specifically, eight miRNAs were first divided into four types according to the difference of bases in the domains 2 and 3 on sequences. To identify the type of targets, a DNA logic gate was constructed with two strand displacement reactions on magnetic beads that could be initiated by different types of targets. Based on the difference of the output signals after two strand displacement reactions, the type of targets was distinguished preliminarily. Then, the discrimination of a specific target was achieved with EDC-based lanthanide labeling ICP-MS detection. By labeling the different magnetic probes with different elemental tags, a specific element signal released from magnetic beads after EDC could be detected by ICP-MS, and therefore, simultaneous detection of homologous sequences was completed. This work provided a novel and simple method for highly specific identification of homologous sequences with the assistance of a logic gate and can promote further development of elemental labeling ICP-MS in the field of multiple analysis.

4.
Small ; 20(7): e2305494, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37797191

RESUMO

Lithium-sulfur (Li-S) batteries hold the superiority of eminent theoretical energy density (2600 Wh kg-1 ). However, the ponderous sulfur reduction reaction and the issue of polysulfide shuttling pose significant obstacles to achieving the practical wide-temperature operation of Li-S batteries. Herein, a covalent organic nanosheet-wrapped carbon nanotubes (denoted CON/CNT) composite is synthesized as an electrocatalyst for wide-temperature Li-S batteries. The design incorporates the CON skeleton, which contains imide and triazine functional units capable of chemically adsorbing polysulfides, and the underlaid CNTs facilitate the conversion of captured polysulfides enabled by enhanced conductivity. The electrocatalytic behavior and chemical interplay between polysulfides and the CON/CNT interlayer are elucidated by in situ X-ray diffraction detections and theoretical calculations. Resultantly, the CON/CNT-modified cells demonstrate upgraded performances, including wide-temperature operation ranging from 0 to 65 °C, high-rate performance (625 mAh g-1 at 5.0 C), exceptional high-rate cyclability (1000 cycles at 5.0 C), and stable operation under high sulfur loading (4.0 mg cm-2 ) and limited electrolyte (5 µL mgs -1 ). These findings might guide the development of advanced Li-S batteries.

5.
Appl Opt ; 63(1): 77-84, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175011

RESUMO

In this paper, an ANLVENet speckle suppression method in holographic phase fringe patterns with different level noises is proposed based on FFDNet, combined with asymmetric pyramid non-local block with a verge extraction module. The experimental results are compared to three network models and several representative algorithms. It is shown that the ANLVENet method not only has better superiority in the speckle suppression with different noise levels, but also preserves more details of the image edge. In addition, another speckle noise model is applied in the phase fringe patterns to prove the stronger generalization of the ANLVENet algorithm. The proposed method is suitable for suppressing the speckle with different levels in a large noise range under complex environmental conditions.

6.
Risk Anal ; 44(2): 459-476, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37330273

RESUMO

The Northern Sea Route (NSR) makes travel between Europe and Asia shorter and quicker than a southern transit via the Strait of Malacca and Suez Canal. It provides greater access to Arctic resources such as oil and gas. As global warming accelerates, melting Arctic ice caps are likely to increase traffic in the NSR and enhance its commercial viability. Due to the harsh Arctic environment imposing threats to the safety of ship navigation, it is necessary to assess Arctic navigation risk to maintain shipping safety. Currently, most studies are focused on the conventional assessment of the risk, which lacks the validation based on actual data. In this study, actual data about Arctic navigation environment and related expert judgments were used to generate a structured data set. Based on the structured data set, extreme gradient boosting (XGBoost) and alternative methods were used to establish models for the assessment of Arctic navigation risk, which were validated using cross-validation. The results show that compared with alternative models, XGBoost models have the best performance in terms of mean absolute errors and root mean squared errors. The XGBoost models can learn and reproduce expert judgments and knowledge for the assessment of Arctic navigation risk. Feature importance (FI) and shapley additive explanations (SHAP) are used to further interpret the relationship between input data and predictions. The application of XGBoost, FI, and SHAP is aimed to improve the safety of Arctic shipping using advanced artificial intelligence techniques. The validated assessment enhances the quality and robustness of assessment.

7.
J Biol Chem ; 298(12): 102665, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36334626

RESUMO

The glucagon receptor (GCGR) is a potential target for diabetes therapy. Several emerging GCGR antagonism-based therapies are under preclinical and clinical development. However, GCGR antagonism, as well as genetically engineered GCGR deficiency in animal models, are accompanied by α-cell hyperplasia and hyperglucagonemia, which may limit the application of GCGR antagonism. To better understand the physiological changes in α cells following GCGR disruption, we performed single cell sequencing of α cells isolated from control and gcgr-/- (glucagon receptor deficient) zebrafish. Interestingly, beyond the α-cell hyperplasia, we also found that the expression of gcga, gcgb, pnoca, and several glucagon-regulatory transcription factors were dramatically increased in one cluster of gcgr-/- α cells. We further confirmed that glucagon mRNA was upregulated in gcgr-/- animals by in situ hybridization and that glucagon promoter activity was increased in gcgr-/-;Tg(gcga:GFP) reporter zebrafish. We also demonstrated that gcgr-/- α cells had increased glucagon protein levels and increased granules after GCGR disruption. Intriguingly, the increased mRNA and protein levels could be suppressed by treatment with high-level glucose or knockdown of the pnoca gene. In conclusion, these data demonstrated that GCGR deficiency not only induced α-cell hyperplasia but also increased glucagon expression in α cells, findings which provide more information about physiological changes in α-cells when the GCGR is disrupted.


Assuntos
Glucagon , Receptores de Glucagon , Animais , Receptores de Glucagon/genética , Receptores de Glucagon/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Hiperplasia , RNA Mensageiro
8.
Anal Chem ; 95(26): 10096-10104, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37351925

RESUMO

In this work, a potential-resolved electrochemiluminescence (ECL) multiplex immunoassay (MIA) was developed using zirconium-based metal-organic framework (MOF) nanoparticles with intense self-ECL as an anodic ECL tag and CdTe nanocrystals (NCs) as a cathodic ECL tag. ECL luminophore 5,5'-(anthracene-9,10-diyl)diisophthalic acid (H4ADIP) and coreactant hexamethylenetetramine (HMT) bound to zirconium nodes in the MOF, giving Zr-ADIP-HMT nanoparticles. Benefiting from the intrareticular charge transfer (ICT) between the oxidized ligands of H4ADIP and HMT via hydrogen bonds, the intense self-ECL from Zr-ADIP-HMT was applied to the potential-resolved ECL MIA without an exogenous anodic coreactant, which can eliminate detrimental effects of multiplex coreactants and anodic ECL emission from CdTe NCs. The ICT within Zr-ADIP-HMT nanoparticles could shorten the electron transport path and reduce the complexity of radical intermediate transport. The ECL intensity from Zr-ADIP-HMT was 18.6-fold that from the mixture of H4ADIP and HMT. In potential-resolved ECL MIA, two lung cancer biomarkers, carcinoembryonic antigen and neuron-specific enolase, were adopted as model analytes, with detection limits of 18 and 5.3 fg·mL-1, respectively. The dual-ligand Zr-ADIP-HMT nanoparticles provide a proof of concept using ICT-based self-ECL luminophores for potential-resolved ECL MIAs with isolated coreactants.


Assuntos
Técnicas Biossensoriais , Compostos de Cádmio , Nanopartículas Metálicas , Estruturas Metalorgânicas , Nanopartículas , Pontos Quânticos , Estruturas Metalorgânicas/química , Zircônio , Compostos de Cádmio/química , Técnicas Eletroquímicas , Medições Luminescentes , Telúrio/química , Nanopartículas/química , Imunoensaio , Nanopartículas Metálicas/química , Limite de Detecção
9.
Biochem Biophys Res Commun ; 643: 121-128, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36596263

RESUMO

Glucagon receptor plays an important role in the regulation of glucose metabolism. Studies have revealed that glucagon receptor antagonism is a potential effective treatment for diabetes. However, the functions of GCGR have not been fully illustrated. Although two Gcgr truncation knockout mice models have been widely used for GCGR function studies, truncated gene may remain neomorphic and/or dominant-negative function. In this study, we took the advantages of Crispr-Cas9 technique and generated a novel allele of GCGR in the mouse that yields complete loss of GCGR protein. Our studies reveal that complete deletion of Gcgr results in hyperglucagonemia, α-cell hyperplasia, improvement of glucose tolerance. These results are similar to the Gcgr-truncated mutation in mice. Hence, we provide a novel strain of GCGR knockout mice for the GCGR function studies.


Assuntos
Sistemas CRISPR-Cas , Receptores de Glucagon , Animais , Camundongos , Receptores de Glucagon/genética , Hiperplasia/genética , Glucagon/genética , Glucagon/metabolismo , Camundongos Knockout
10.
Chem Rec ; 23(11): e202300146, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37283443

RESUMO

Preparing valuable olefins from cheap and abundant alkane resources has long been a challenging task in organic synthesis, which mainly suffers from harsh reaction conditions and narrow scopes. Homogeneous transition metals catalyzed dehydrogenation of alkanes has attracted much attention for its excellent catalytic activities under relatively milder conditions. Among them, base metal catalyzed oxidative alkane dehydrogenation has emerged as a viable strategy for olefin synthesis for its usage of cheap catalysts, compatibility with various functional groups, and low reaction temperature. In this review, we discuss recent development of base metal catalyzed alkane dehydrogenation under oxidative conditions and their application in constructing complex molecules.

11.
Sensors (Basel) ; 23(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37112222

RESUMO

Monitoring of uric acid (UA) levels in biological samples is of great significance for human health, while the development of a simple and effective method for the precise determination of UA content is still challenging. In the present study, a two-dimensional (2D) imine-linked crystalline pyridine-based covalent organic framework (TpBpy COF) was synthesized using 2,4,6-triformylphloroglucinol (Tp) and [2,2'-bipyridine]-5,5'-diamine (Bpy) as precursors via Schiff-base condensation reactions and was characterized with scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDS), Powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy, and Brunauer-Emmett-Teller (BET) assays. The as-synthesized TpBpy COF exhibited excellent visible light-induced oxidase-like activity, ascribed to the generation of superoxide radicals (O2•-) by photo-generated electron transfer. TpBpy COF could efficiently oxidase the colorless substrate 3,3',5,5'-tetramethylbenzydine (TMB) into blue oxidized TMB (oxTMB) under visible light irradiation. Based on the color fade of the TpBpy COF + TMB system by UA, a colorimetric procedure was developed for UA determination with a detection limit of 1.7 µmol L-1. Moreover, a smartphone-based sensing platform was also constructed for instrument-free and on-site detection of UA with a sensitive detection limit of 3.1 µmol L-1. The developed sensing system was adopted for UA determination in human urine and serum samples with satisfactory recoveries (96.6-107.8%), suggesting the potential practical application of the TpBpy COF-based sensor for UA detection in biological samples.


Assuntos
Estruturas Metalorgânicas , Oxirredutases , Humanos , Ácido Úrico/urina , Estruturas Metalorgânicas/química , Colorimetria/métodos , Smartphone , Espectroscopia de Infravermelho com Transformada de Fourier , Sistemas Automatizados de Assistência Junto ao Leito , Luz
12.
Acta Chir Belg ; 123(3): 313-316, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34753409

RESUMO

BACKGROUND: Sarcoidosis is a multi-system, idiopathic, inflammatory disorder that affects the lungs in over 90% of patients. The incidence of bone lesions in sarcoidosis is only 1-13%. CASE REPORT: This study describes a 60-year-old woman with a previous history of thyroid cancer, and a more recent diagnosis of lung cancer with suspicious metastatic lesions, which were confirmed to be sarcoidosis. CONCLUSION: This case suggests that pulmonary neoplasms and pulmonary sarcoidosis can coexist and be easily confused. When lung cancer is accompanied by symmetric hilar lymph node enlargement and multiple lung nodules, sarcoidosis should be considered in addition to metastasis, and a biopsy should be performed for confirmation.


Assuntos
Neoplasias Pulmonares , Doenças do Mediastino , Sarcoidose Pulmonar , Sarcoidose , Feminino , Humanos , Pessoa de Meia-Idade , Sarcoidose Pulmonar/complicações , Sarcoidose Pulmonar/diagnóstico , Sarcoidose Pulmonar/patologia , Sarcoidose/complicações , Sarcoidose/diagnóstico , Sarcoidose/patologia , Neoplasias Pulmonares/patologia , Pulmão
13.
Angew Chem Int Ed Engl ; 62(24): e202302908, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37062703

RESUMO

Fluoroalkyl aryl ethers are valuable structural motifs in pharmaceuticals because compounds with these motifs are more metabolically stable and more lipophilic than their nonfluorinated analogues. However, hexafluoroisopropyl aryl ethers have not been extensively studied, presumably because of the lack of efficient synthetic methods. Herein, we describe a rhodium-catalyzed nucleophilic aromatic substitution of aryl chlorides or bromides, which act as the limiting reagents, with weakly nucleophilic hexafluoro-2-propanol under mild reaction conditions. This method provides diverse hexafluoroisopropyl aryl ethers. We demonstrated the generality of this method by carrying out reactions of a large array of unactivated aryl halides, and we found that the success of the reactions relied on arene activation by means of η6 -coordination.

14.
J Am Chem Soc ; 144(3): 1144-1151, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-35015956

RESUMO

Given the wide prevalence and ready availability of both phenols and amines, aniline synthesis through direct coupling between these starting materials would be extremely attractive. Herein, we describe a rhodium-catalyzed amination of phenols, which provides concise access to diverse anilines, with water as the sole byproduct. The arenophilic rhodium catalyst facilitates the inherently difficult keto-enol tautomerization of phenols by means of π-coordination, allowing for the subsequent dehydrative condensation with amines. We demonstrate the generality of this redox-neutral catalysis by carrying out reactions of a large array of phenols with various electronic properties and a wide variety of primary and secondary amines. Several examples of late-stage functionalization of structurally complex bioactive molecules, including pharmaceuticals, further illustrate the potential broad utility of the method.

15.
Anal Chem ; 94(37): 12934-12941, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36070565

RESUMO

Inductively coupled plasma-mass spectrometry (ICP-MS) with elemental labeling is a promising strategy for multiplex microRNA (miRNA) analysis. However, it is still challenging for specific analysis of multiple miRNAs with high homology, and the development of multiplex assays is always limited by the complexity of the sequence design. Herein, a simple and direct ICP-MS-based assay was developed for the simultaneous detection of three miRNAs by combining the lanthanide labeling strategy with entropy-driven catalytic (EDC) amplification. Owing to the specificity of EDC for nucleic acid recognition, it is able to differentiate miRNAs with single-base mutation in each EDC circuit. A universal biotin-labeled DNA strand was designed to hybridize with the DNA substrates for three EDC circuits, targeting miRNA-21, miRNA-155, and miRNA-10b, respectively. All the substrates were loaded on the surface of streptavidin magnetic beads. In the presence of target miRNA, the EDC reaction was initiated, and EDC substrates were dissociated, continuously releasing reporter strands that were labeled with lanthanides (Tb/Ho/Lu). After magnetic separation, the supernatant containing the released reporter strands was introduced into an ICP-MS system for simultaneous detection of 159Tb/165Ho/175Lu and quantification of miRNA-21, miRNA-155, and miRNA-10b, respectively. The limits of detection were 7.4, 7.5, and 11 pmol L-1 for miRNA-21, miRNA-155, and miRNA-10b, respectively. Overall, this study provides a powerful strategy for simultaneous quantification of multiple miRNAs, with the advantages of flexible probe design, good sensitivity, and excellent specificity.


Assuntos
Elementos da Série dos Lantanídeos , MicroRNAs , Biotina , DNA/química , Elementos da Série dos Lantanídeos/química , MicroRNAs/análise , Estreptavidina
16.
Anal Chem ; 94(8): 3637-3644, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35187927

RESUMO

The intensity of electrochemiluminescence (ECL) usually changes rapidly with the progress of the electrochemical process, making it difficult to determine the ECL spectrum with a conventional photomultiplier in a wavelength scan model. Herein, a band-pass filter (BPF)-involved modulating strategy is proposed to upgrade a conventional ECL analyzer to a highly sensitive ECL spectrometer without changing its hardware. The ECL spectrum can be figured out by rapidly and/or continuously modulating a part of the ECL intensity-time curve with a BPF array of different central wavelengths as well as correcting the ECL intensity at different measurement times by a univariate cubic polynomial model. This strategy not only can determine the spectrum of ultra-weak emission with high sensitivity via merely modulating the emission within a short period, including the weak self-ECL from either Ru(bpy)32+ or tripropylamine (TPA), but also can demonstrate the interaction between the co-existing emitters. It is shown that the ECL from both Ru(bpy)32+ and TPA of the Ru(bpy)32+/TPA system can be mutually promoted in electrochemical potential and in a concentration-dependent way. The self-ECL of TPA at the potential of 1.24 V can be enhanced from 4.9- to 51-fold with the Ru(bpy)32+ concentration increasing from 0.01 to 0.8 µM. In the presence of 0.04 µM Ru(bpy)32+, the self-ECL of TPA is enhanced by 94- and 10.2-fold at the potential of 1.01 and 1.76 V, respectively. The portable inexpensive BPF turntable device is also useful in spectrum-resolved multi-analyte determination and ratiometric ECL biosensors.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Medições Luminescentes
17.
Anal Chem ; 94(46): 16069-16078, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36356236

RESUMO

Microneedles (MNs) are currently one of the most promising tools for skin interstitial fluid (ISF)-based biosensing, while it is still a challenge to expand the detectable biomarkers in ISF due to limited MNs types and detection techniques. Herein, highly sensitive internal-standard surface-enhanced Raman scattering microneedles (IS-SERS-MNs) were developed, which enabled the reliable detection of bacterial metabolites in ISF as new detectable biomarkers for infection diagnosis. The developed IS-SERS-MNs can not only directly detect pyocyanin (a representative bacterial metabolite) present in mouse dermal ISF but also indirectly detect pyocyanin in the hypodermis via its diffusion into the dermis, revealing a new possible pathway for the source of biomarkers in dermal ISF. Moreover, the SERS signal of pyocyanin was also clearly detected at real mouse wounds, indicating that the developed IS-SERS-MNs have great potential in minimally invasive and painless diagnosis of bacterial infection via a new ISF route. This work not only develops IS-SERS-MNs as a powerful tool for expanding the application of SERS-based MNs but also provides a new chance for ISF-related infection diagnosis.


Assuntos
Líquido Extracelular , Análise Espectral Raman , Camundongos , Animais , Líquido Extracelular/metabolismo , Agulhas , Piocianina , Pele/metabolismo , Biomarcadores/metabolismo
18.
Anticancer Drugs ; 33(1): e247-e259, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34387601

RESUMO

Accumulating evidence insists that circular RNAs (circRNAs) play important roles in the development of human cancers, including gastric cancer. This study aimed to investigate the role of circ-SFMBT2 and provide a potential mechanism to explain its function. The expression of circ-SFMBT2, miR-885-3p and chromodomain-helicase-DNA-binding protein 7 (CHD7) mRNA was determined by quantitative real-time PCR (qRT-PCR), and the protein level of CHD7 was determined by western blot. To investigate the function of circ-SFMBT2 in vitro, the effects of circ-SFMBT2 on cell viability, colony formation, apoptosis, migration and invasion were assessed using cell counting kit-8 assay, colony formation assay, flow cytometry assay, wounding healing assay and transwell assay, respectively. The indicators of oxidative stress were assessed using matched kits. Besides, the function of circ-SFMBT2 was also investigated in animal models. The relationship between miR-885-3p and circ-SFMBT2 or CHD7 was verified by dual-luciferase reporter assay and RNA immunoprecipitation assay. Circ-SFMBT2 and CHD7 were upregulated, whereas miR-885-3p was downregulated in gastric cancer tissues and cells. In functional assay, circ-SFMBT2 knockdown suppressed gastric cancer cell viability, colony formation ability, migration, invasion and oxidative stress but induced apoptosis, and circ-SFMBT2 downregulation also blocked tumor growth in vivo. In mechanism analysis, circ-SFMBT2 regulated CHD7 expression by sponging its target miRNA, miR-885-3p. Rescue experiments manifested that miR-885-3p inhibition reversed the effects of circ-SFMBT2 knockdown, and CHD7 overexpression abolished the antitumor role of miR-885-3p overexpression. Moreover, circ-SFMBT2 knockdown inactivated the Wnt/ß-catenin signaling pathway. Circ-SFMBT2 downregulation repressed the development of gastric cancer partially by controlling the miR-885-3p/CHD7 axis, which might be a novel strategy to inhibit gastric cancer progression.


Assuntos
DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , MicroRNAs/metabolismo , RNA Circular/genética , Proteínas Repressoras/genética , Neoplasias Gástricas/patologia , Apoptose/fisiologia , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/fisiologia , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Regulação para Cima , Via de Sinalização Wnt/fisiologia , beta Catenina/metabolismo
19.
Int J Mol Sci ; 23(7)2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35409019

RESUMO

In search of new therapies for pancreatic cancer, cytokine pathways have attracted increasing interest in recent years. Cytokines play a vital role in the crosstalk between tumour cells and the tumour microenvironment. The related inflammatory cytokines IL-4 and IL-13 can regularly be detected at increased levels in the microenvironment of pancreatic cancer. They share a receptor heterodimer consisting of IL-4Rα and IL-13Rα1. While IL-4Rα induces a more oncogenic phenotype, the role of IL-13Rα1 was yet to be determined. ShRNA-based knockdown of IL-13Rα1 was performed in Capan-1 and MIA PaCa-2. We assessed cell growth and migratory capacities under the influence of IL-13Rα1. Pathway alterations were detected by immunoblot analysis. We now have demonstrated that the loss of IL-13Rα1 induces apoptosis in pancreatic cancer cells. This was associated with an epithelial-to-mesenchymal transition. Loss of IL-13Rα1 also abolished the effects of exogenous IL-4 and IL-13 stimulation. Interestingly, in wild type cells, cytokine stimulation caused a similar increase in migratory capacities as after IL-13Rα1 knockdown. Overall, our results indicate the vital role of IL-13Rα1 in the progression of pancreatic cancer. The differential expression of IL-4Rα and IL-13Rα1 has to be taken into account when considering a cytokine-targeted therapy in pancreatic cancer.


Assuntos
Interleucina-13 , Neoplasias Pancreáticas , Apoptose , Citocinas/metabolismo , Humanos , Interleucina-13/farmacologia , Subunidade alfa1 de Receptor de Interleucina-13/genética , Interleucina-4/metabolismo , Interleucina-4/farmacologia , Neoplasias Pancreáticas/genética , Microambiente Tumoral , Neoplasias Pancreáticas
20.
Artigo em Inglês | MEDLINE | ID: mdl-35464041

RESUMO

In 2020, the COVID-19 pandemic was a major public health emergency on a global scale. The literature regarding the pandemic and its impact on academic libraries is still rising. This article examines the two-year process of developing a flexible service scenario and the broader picture by analyzing data on Chinese top university libraries' programmes and outreach initiatives prior to, during, and the normal COVID-19 pandemic (Sept. 2019-Sept. 2021). COVID-19 is found to have a significant impact on the physical space, collection development, and service of the library, demonstrating the characteristics of space access restricted by security measures, collection digitization, and online service. This research also examines the previous year's initiatives and programmes and discusses the next phase of "new normal" procedures. Hopefully, this study will give insight on how Chinese libraries responded to the recent pandemic, informing libraries' outreach and efforts to be better prepared to take imperative, swift, and decisive action in the post-COVID-19 era and beyond.

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