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1.
Org Biomol Chem ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623736

RESUMO

Herein, we report a visible light-enabled radical trihalomethylation/cyano-migration/carbonylation cascade reaction of 2-hydroxy-2-hex-5-enenitrile with CX3SO2Cl as the CX3-source (X = F, Cl) to obtain 5-oxo-2-(2,2,2-trihaloethyl)pentanenitrile compounds in the absence of a photocatalyst, transition metal and base. This reaction system is also effective to convert (benzo[d]thiazol-2-yl)-pent-4-enol to the corresponding 4-(benzo[d]thiazol-2-yl)-6,6,6-trihalo-hexanone products. These reactions occur under mild conditions, tolerate a wide range of functional groups, and provide alternative approaches for the 1,2-bifunctionalization reaction of unactivated olefins.

2.
Dent Mater ; 40(4): e1-e11, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38365456

RESUMO

OBJECTIVE: This study aimed to evaluate the combined effects of sulfonation, non-thermal oxygen plasma and silane on the shear bond strength (SBS) of PEEK to resin materials. MATERIALS AND METHODS: Two hundred and eighty specimens were randomly divided into four groups: (A) untreated; (B) sulfonation for 60 s; (C) oxygen plasma for 20 min; (D) sulfonation for 60 s and oxygen plasma for 20 min. According to the instructions, 120 samples (N = 30) were coated with silane, adhesive, and resin composites. Each group of bonding specimens was divided into two subgroups (n = 15) to measure immediate and post-aging SBS. The surface morphology and the interface between the samples and adhesive were analyzed through SEM. Physicochemical characteristics of the surface and mechanical properties were determined through XPS, FTIR, light interferometry, contact angle measurement, and three-point bending tests. RESULTS: Sulfonation produced a porous layer of approximately 20 µm thickness on the surface, and the oxygen plasma increased the O/C ratio and oxygen-containing groups of the sample surface. After coating with silane, the SBS values of sulfonated PEEK and plasma-treated PEEK increased (9.96 and 10.72 MPa, respectively), and dual-modified PEEK exhibited the highest SBS value (20.99 MPa), which was significantly higher than that of blank group (p > 0.01). After 10,000 thermal cycles, the dual-modified PEEK still displayed a favorable SBS (18.68 MPa). SIGNIFICANCE: Sulfonation strengthened the mechanical interlocking between PEEK and the resin while oxygen plasma established a chemical bonding between silane and PEEK. This dual modification of the surface microstructure and chemical state synergistically improved the bond strength of PEEK to resin and resulted in considerable long-term effects.


Assuntos
Benzofenonas , Colagem Dentária , Cimentos Dentários , Polímeros , Cimentos Dentários/química , Silanos/química , Polietilenoglicóis/química , Cimentos de Resina/química , Colagem Dentária/métodos , Oxigênio , Propriedades de Superfície , Resistência ao Cisalhamento , Teste de Materiais
3.
Autophagy ; 20(1): 151-165, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37651673

RESUMO

ABBREVIATIONS: AKI: acute kidney injury; ATP: adenosine triphosphate; BUN: blood urea nitrogen; CLP: cecal ligation and puncture; eGFR: estimated glomerular filtration rate; H&E: hematoxylin and eosin staining; LCN2/NGAL: lipocalin 2; LPS: lipopolysaccharide; LTL: lotus tetragonolobus lectin; mKeima: mitochondria-targeted Keima; mtDNA: mitochondrial DNA; PAS: periodic acid - Schiff staining; RTECs: renal tubular epithelial cells; SAKI: sepsis-induced acute kidney injury; Scr: serum creatinine; SIRT3: sirtuin 3; TFAM: transcription factor A, mitochondrial; TMRE: tetramethylrhodamine.


Assuntos
Injúria Renal Aguda , Melatonina , Sepse , Sirtuína 3 , Humanos , Mitofagia , Autofagia , Lipopolissacarídeos , DNA Mitocondrial , Sepse/complicações , Rim , Proteínas de Ligação a DNA , Fatores de Transcrição , Proteínas Mitocondriais
4.
Epigenetics ; 18(1): 2278960, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37979155

RESUMO

Sepsis is the primary cause of acute kidney injury (AKI) and is associated with high mortality rates. Growing evidence suggests that noncoding RNAs are vitally involved in kidney illnesses, whereas the role of circular RNAs (circRNAs) in sepsis-induced AKI (SAKI) remains largely unknown. In this present study, caecal ligation and puncture (CLP) in mice was performed to establish an SAKI model. The expression of circRNAs and mRNAs was analysed using circRNA microarray or next-generation sequencing. The results revealed that the expressions of 197 circRNAs and 2509 mRNAs were dysregulated. Validation of the selected circRNAs was performed by qRT-PCR. Bioinformatics analyses and chromatin immunoprecipitation demonstrated that NF-κB/p65 signalling induced the upregulation of circC3, circZbtb16, and circFkbp5 and their linear counterparts by p65 transcription in mouse tubular epithelial cells (mTECs). Furthermore, competitive endogenous RNA (ceRNA) networks demonstrated that some components of NF-κB signalling were potential targets of these dysregulated circRNAs. Among them, Tnf-α was increased by circFkbp5 through the downregulation of miR-760-3p in lipopolysaccharide (LPS)-stimulated mTECs. Knocking down circFkbp5 inhibited the p65 phosphorylation and apoptosis in injured mTECs. These findings suggest that the selected circRNAs and the related ceRNA networks provide new knowledge into the fundamental mechanism of SAKI and circFkbp5/miR-760-3p/Tnf-α axis might be therapeutic targets.


Assuntos
Injúria Renal Aguda , MicroRNAs , Sepse , Camundongos , Animais , RNA Circular/genética , MicroRNAs/genética , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Metilação de DNA , RNA Mensageiro/genética , Injúria Renal Aguda/genética , Sepse/complicações , Sepse/genética
5.
Polymers (Basel) ; 15(18)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37765520

RESUMO

Multifunctional biofilms with early fire-warning capabilities are highly necessary for various indoor and outdoor applications, but a rational design of intelligent fire alarm films with strong weather resistance remains a major challenge. Herein, a multiscale hierarchical biofilm based on lignocellulose nanofibrils (LCNFs), carbon nanotubes (CNTs) and TiO2 was developed through a vacuum-assisted alternate self-assembly and dipping method. Then, an early fire-warning system that changes from an insulating state to a conductive one was designed, relying on the rapid carbonization of LCNFs together with the unique electronic excitation characteristics of TiO2. Typically, the L-CNT-TiO2 film exhibited an ultrasensitive fire-response signal of ~0.30 s and a long-term warning time of ~1238 s when a fire disaster was about to occur, demonstrating a reliable fire-alarm performance and promising flame-resistance ability. More importantly, the L-CNT-TiO2 biofilm also possessed a water contact angle (WCA) of 166 ± 1° and an ultraviolet protection factor (UPF) as high as 2000, resulting in excellent superhydrophobicity, antifouling, self-cleaning as well as incredible anti-ultraviolet (UV) capabilities. This work offers an innovative strategy for developing advanced intelligent films for fire safety and prevention applications, which holds great promise for the field of building materials.

6.
Chem Asian J ; 18(14): e202300330, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37300365

RESUMO

A direct protocol for Rh-catalyzed C-H amidation of ferrocenes in a ball mill using dioxazolones as the amide source under solvent-free conditions was developed. The corresponding ortho-aminated products were formed in 3 hours and the yields were up to 99% in the absence of base. This method could be a typically sustainable and environmental-friendly alternative method to traditional methodologies, with the advantages of wide substrate range, good functional group tolerance and gram-scale synthesis.

7.
ACS Appl Mater Interfaces ; 15(22): 27034-27045, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37232292

RESUMO

Ionic current measurement has been the dominant signaling strategy in nanochannel-based sensors. However, the direct probing of the capture of small molecules is still challenging, and the sensing potential of the outer surface of nanochannels is always ignored. Here, we report the fabrication of an integrated nanochannel electrode (INCE) with nanoporous gold layers modified on two sides of nanochannels, and its application for small-molecule analysis was explored. Metal-organic frameworks (MOFs) were decorated inside and outside of nanochannels, enabling the reduction of pore size to several nanometers, which is among the thickness range of the electric double layer for confined ion diffusion. Combined with excellent adsorption characteristics of MOFs, the developed nanochannel sensor successfully constructed the internal nanoconfined space that could directly capture small molecules and instantly generate a current signal. The contribution of the outer surface and the internal nanoconfined space to diffusion suppression to electrochemical probes was investigated. We found that the constructed nanoelectrochemical cell was sensitive in both the inner channel and the outer surface, signifying a novel sensing mode with integration of the internal nanoconfined space and the outer surface of nanochannels. The MOF/INCE sensor showed excellent performance toward tetracycline (TC) with a detection limit of 0.1 ng·mL-1. Subsequently, sensitive and quantitative detection of TC down to 0.5 µg·kg-1 was achieved in actual chicken samples. This work may open up a new model of nanoelectrochemistry and provide an alternative solution in the field of nanopore analysis for small molecules.

8.
ACS Appl Mater Interfaces ; 15(13): 17222-17232, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36877589

RESUMO

Balancing the trade-off between permeability and selectivity while realizing multiple sieving from complex matrices remains as bottlenecks for membrane-based separation. Here, a unique nanolaminate film of transition metal carbide (MXene) nanosheets intercalated by metal-organic framework (MOF) nanoparticles was developed. The intercalation of MOFs modulated the interlayer spacing and created nanochannels between MXene nanosheets, promoting a fast water permeance of 231 L m-2 h-1 bar-1. The nanochannel endowed a 10-fold lengthened diffusion path and the nanoconfinement effect to enhance the collision probability, establishing an adsorption model with a separation performance above 99% to chemicals and nanoparticles. In addition to the remained rejection function of nanosheets, the film integrated dual separation mechanisms of both size exclusion and selective adsorption, enabling a rapid and selective liquid phase separation paradigm that performs simultaneous multiple chemicals and nanoparticles sieving. The unique MXenes-MOF nanolaminate film and multiple sieving concepts are expected to pave a promising way toward highly efficient membranes and additional water treatment applications.

9.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 39(1): 15-20, 2023 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-36631010

RESUMO

Objective To investigate the effect of PDS5B on the biological function of A549 human lung cancer cells and possible molecular mechanism. Methods The proliferation of lung cancer cells was detected by MTT assay and colony formation assay after silencing or overexpressing PDS5B of A549 cells. The cell migration was detected by scratch assay and TranswellTM assay. The protein expression of PDS5B and Wnt5a in A549 cells was detected by Western blot analysis. Cell migration was detected by TranswellTM after PDS5B small interference RNA(siRNA) and Wnt5a siRNA were co-transfected. Results Compared with the negative control group, the protein expression of PDS5B decreased significantly after transfected with PDS5B siRNA. The proliferation ability , colony formation rate and migration ability of A549 cells significantly improved, and the expression of Wnt5a was increased. The opposite results were observed after PDS5B over-expression. The co-transfer experiment showed that Wnt5a could resist the inhibition of A549 cells by PDS5B. Conclusion PDS5B inhibits lung cancer cell proliferation by down-regulating Wnt5a expression.


Assuntos
Proliferação de Células , Proteínas de Ligação a DNA , Neoplasias Pulmonares , Fatores de Transcrição , Proteína Wnt-5a , Humanos , Células A549 , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Proteínas de Ligação a DNA/genética , Regulação para Baixo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Fatores de Transcrição/metabolismo , Proteína Wnt-5a/genética , Proteína Wnt-5a/metabolismo
10.
Adv Colloid Interface Sci ; 311: 102828, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36587470

RESUMO

Sensitive and facile detection of analytes is crucial in various fields such as agriculture production, food safety, clinical diagnosis and therapy, and environmental monitoring. However, the synergy of complicated sample pretreatment and detection is an urgent challenge. By integrating the inherent porosity, processability and flexibility of films and the diversified merits of nanomaterials, nanomaterial-based films have evolved as preferred candidates to meet the above challenge. Recent years have witnessed the flourishment of films-based detection technologies due to their unique porous structures and integrated physical/chemical merits, which favors the separation/collection and detection of analytes in a rapid, efficient and facile way. In particular, films based on nanomaterials consisting of 0D metal-organic framework particles, 1D nanofibers and carbon nanotubes, and 2D graphene and analogs have drawn increasing attention due to incorporating new properties from nanomaterials. This paper summarizes the progress of the fabrication of emerging films based on nanomaterials and their detection applications in recent five years, focusing on typical electrochemical and optical methods. Some new interesting applications, such as point-of-care testing, wearable devices and detection chips, are proposed and emphasized. This review will provide insights into the integration and processability of films based on nanomaterials, thus stimulate further contributions towards films based on nanomaterials for high-performance analytical-chemistry-related applications.


Assuntos
Técnicas Biossensoriais , Grafite , Nanoestruturas , Nanotubos de Carbono , Nanotubos de Carbono/química , Técnicas Biossensoriais/métodos , Nanoestruturas/química , Grafite/química , Monitoramento Ambiental
11.
Sensors (Basel) ; 22(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36365938

RESUMO

In order to solve the demand for low-power microcomputers and micro-electro-mechanical system components for continuous energy supply, a magnetic coupling piezoelectric-electromagnetic composite galloping energy harvester (MPEGEH) is proposed. It is composed of a piezoelectric energy harvester (PEH) and an electromagnetic energy harvester (EEH) coupled by magnetic force. The bistable nonlinear magnetic coupling structure improves the output power of the MPEGEH. The advantages and output performance of the MPEGEH are analyzed. The prototype of the energy harvester is made, and the nonlinear output characteristics under different load resistances are analyzed. Through the experiment on the key parameters of the composite energy harvester, it is found that the higher the coupling degree of the two parts of the MPEGEH, the stronger the nonlinear characteristics and the better the output characteristics. The results show that the onset wind velocity and output power of the MPEGEH are better than the classic galloping piezoelectric energy harvester (CGPEH). At the same wind speed, with the increase in the distance d0 between magnets A and B, the output power of both the PEH and the EEH decreases. When d0 is 37 mm, the output power of the EEH is the largest. The distance s0 between magnets B and C has little influence on the output power of the PEH but has a great influence on the EEH. When s0 is 23 mm, the EEH has the best output characteristics. Compared with the CGPEH, the onset wind velocity is reduced by 28%, and the output power is increased by 136% when the wind speed is 11 m/s.

12.
J Org Chem ; 87(19): 12877-12889, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36074642

RESUMO

We report the visible-light-induced Ph3P/LiI-promoted intermolecular cascade trifluoromethyl radical addition/5-exo-dig cyclization/iodination of 1,6-enynes with Togni's reagent using LiI as the iodine source without the need of the transition metal, oxidant, and base. This reaction promises to be a useful method for the preparation of trifluoromethyl-substituted and vinyl C-I bond-containing pyrrolidines and benzofuran products with good regioselectivity and functional-group tolerance under ambient conditions.

14.
Biosens Bioelectron ; 216: 114659, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36095979

RESUMO

Pesticide residues have raised serious public concern towards agriculture, environment and food safety. Recently, metal-organic frameworks (MOFs) have been employed as promising recognition and signal generation elements in sensors for pesticide detection. However, the general format of tiny particles with poor dispersity brings obstacles to detection operation and the improvement of sensing performance. Here, we report a sensor based on porous MOFs hybrid sponge for fluorescent-visible detection of methyl parathion. Benefiting from the intermediate of adhesive and porous fibrin film, MOFs are loaded with good dispersion and accessibility, thereby endowing the sensor with a rapid response time of 10-min, a wide linear detection range of 50-2500 µg L-1, and a low limit of detection of 4.95 µg L-1. Moreover, the hybrid sensor presented superior durability and anti-interference ability to the detection in complex conditions, including organic solvents, acidic solution, high temperature, and even chemical interferences. This hybrid not only provides a new construction strategy for a nanomaterial-based sensor, but also permits a portable and durable route for the detection.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Metil Paration , Resíduos de Praguicidas , Praguicidas , Fibrina , Estruturas Metalorgânicas/química , Compostos Organofosforados , Porosidade , Solventes
15.
Mol Ther ; 30(10): 3313-3332, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-35619557

RESUMO

Acute kidney injury (AKI) is increasingly identified as a crucial risk factor for progression to CKD. However, the factors governing AKI to CKD progression remain largely unknown. By high-throughput RNA sequencing, we found that Neat1_2, a transcript variant of Neat1, was upregulated in 40-min ischemia/reperfusion injury (IRI), which resulted in the development of renal fibrotic lesions. The upregulation of Neat1_2 in hypoxia-treated TECs was attributed to p53 transcriptional regulation. Gain- and loss-of-function studies, both in vitro and in vivo, demonstrated that Neat1_2 promoted apoptosis of injured TECs induced by IRI and caused tubulointerstitial inflammation and fibrosis. Mechanistically, Neat1_2 shares miRNA response elements with FADD, CASP-8, and CASP-3. Neat1_2 competitively binds to miR-129-5p and prevents miR-129-5p from decreasing the levels of FADD, CASP-8, and CASP-3, and ultimately facilitates TEC apoptosis. Increased expression of Neat1_2 associated with kidney injury and TEC apoptosis was recapitulated in human AKI, highlighting its clinical relevance. These findings suggest that preventing TEC apoptosis by hindering Neat1_2 expression may be a potential therapeutic strategy for AKI to CKD progression.


Assuntos
Injúria Renal Aguda , MicroRNAs , RNA Longo não Codificante , Insuficiência Renal Crônica , Injúria Renal Aguda/genética , Injúria Renal Aguda/metabolismo , Apoptose/genética , Células Epiteliais/metabolismo , Fibrose , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/patologia , Proteína Supressora de Tumor p53/metabolismo
16.
Theranostics ; 12(6): 2801-2810, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401815

RESUMO

Background: Gold nanoparticle-based immunochromatographic assay (AuNP-ICA) has insufficient sensitivity due to its inherent colorimetric signal intensity and low capture efficiency of AuNPs. The metal in situ growth is a common strategy to enhance the sensitivity of AuNP-ICA due to its superior signal amplification potential and simple operation. However, the detection distortion caused by metal self-nucleation during the growth process can seriously affect the accuracy and reproducibility of the strips. Methods: We present a pH-regulated gold in situ growth (GISG) strategy to amplify the colorimetric signal and demonstrate its application in improving the performance of traditional AuNP-ICA. The controllable growth signal amplification is achieved by lowering the pH of the growth solution to weaken the reducibility of hydroxylamine (HA), thus urging the crystallization and growth of Au3+ on the AuNP surface instead of free reduction and self-nucleation. In addition, the mechanism of pH regulation on HA reducibility is elucidated by introducing an electron-donating or electron-withdrawing group to affect the electron density of hydroxyl group. Results: The proposed GISG strategy shows improved sensitivity, low background, robust operation, and good reproducibility. The LOD values of the designed GISG-amplified AuNP-ICA are as low as 0.0198 ng mL-1 for hepatitis B surface antigen and 0.0125 ng mL-1 for HIV-1 capsid p24 antigen, which are lower by about 500- and 70-fold, respectively, than those of the unamplified AuNP-ICA. Conclusions: This method is extended to enable ultrasensitive and rapid diagnosis of viral infections, and has potential as a general signal amplification platform to redefine immunochromatographic diagnostics.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Colorimetria , Ouro/química , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes
17.
Front Cell Dev Biol ; 9: 719351, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34631707

RESUMO

Chronic catecholamine stress (CCS) induces the occurrence of cardiomyopathy-pathological cardiac hypertrophy (PCH), which is characterized by left ventricular systolic dysfunction (LVSD). Recently, mounting evidence has implicated myocardial inflammation in the exacerbation of pathological cardiac remodeling. However, there are currently no well-defined treatment interventions or regimes targeted at both the attenuation of maladaptive myocardial hypertrophy and inflammation during CCS to prevent PCH. G protein-coupled receptor kinase 5 (GRK5) and adenylyl cyclases (ACs)-cAMP mediates both cardiac and inflammatory responses. Also, GRK5 and ACs are implicated in stress-induced LVSD. Herein, we aimed at preventing PCH during CCS via modulating adaptive cardiac and inflammatory responses by inhibiting GRK5 and/or stimulating ACs. Isoproterenol-induced cardiomyopathy (ICM) was modeled using 0.5 mg/100 g/day isoproterenol injections for 40 days. Alterations in cardiac and inflammatory responses were assessed from the myocardia. Similarities in the immunogenicity of cardiac troponin I (cTnI) and lipopolysaccharide under CCS were assessed, and Amlexanox (35 µM/ml) and/or Forskolin (10 µM/ml) were then employed in vitro to modulate adaptive inflammatory responses by inhibiting GRK5 or activating ACs-cAMP, respectively. Subsequently, Amlexanox (2.5 mg/100 g/day) and/or Forskolin (0.5 mg/100 g/day) were then translated into in vivo during CCS to modulate adaptive cardiac and inflammatory responses. The effects of Amlexanox and Forskolin on regulating myocardial systolic functions and inflammatory responses during CCS were ascertained afterward. PCH mice had excessive myocardial hypertrophy, fibrosis, and aggravated LVSD, which were accompanied by massive CD68+ inflammatory cell infiltrations. In vitro, Forskolin-AC/cAMP was effective than Amlexanox-GRK5 at downregulating proinflammatory responses during stress; nonetheless, Amlexanox and Forskolin combination demonstrated the most efficacy in modulating adaptive inflammatory responses. Individually, the translated Amlexanox and Forskolin treatment interventions were ineffective at subduing the pathological remodeling and sustaining cardiac function during CCS. However, their combination was potent at preventing LVSD during CCS by attenuating maladaptive myocardial hypertrophy, fibrosis, and inflammatory responses. The treatment intervention attained its potency mainly via Forskolin-ACs/cAMP-mediated modulation of cardiac and inflammatory responses, coupled with Amlexanox inhibition of GRK5 mediated maladaptive cascades. Taken together, our findings highlight the Amlexanox and Forskolin combination as a potential therapeutic intervention for preventing the occurrence of pathological cardiac hypertrophy during chronic stress.

18.
Front Cell Dev Biol ; 9: 737003, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650984

RESUMO

Clinical demographics have demonstrated that postmenopausal women are predisposed to chronic stress-induced cardiomyopathy (CSC) and this has been associated with the decrease of estrogen. Meanwhile, recent studies have implicated unsolved myocardial proinflammatory responses, which are characterized by enormous CD86+ macrophage infiltrations as an underlying disease mechanism expediting the pathological remodeling of the heart during chronic stress. However, we had previously demonstrated that estrogen confers cardioprotection via the modulation of cardiomyocytes ß2-adrenoceptors (ß2AR)-Gs/Gi pathways during stress to lessen the incidence of stress-induced cardiovascular diseases in premenopausal women. Intriguingly, macrophages express ß2AR profoundly as well; as such, we sought to elucidate the possibilities of estrogen modulating ß2AR-Gs/Gi pathway to confer cardioprotection during stress via immunomodulation. To do this, ovariectomy (OVX) and sham operations (Sham) were performed on female Sprague-Dawley (SD) rats. Two weeks after OVX, the rats were injected with 40 µg/kg/day of estradiol (E2). Next, on day 36 after OVX, chronic stress was induced by a daily subcutaneous injection of 5 mg/kg/day of isoproterenol (ISO). The effect of E2 on relevant clinical cardiac function indexes (LVSP, LVEDP, + dp/dt and -dp/dt), myocardial architecture (cardiomyocyte diameter and fibrosis), ß2AR alterations, and macrophage (CD86+ and CD206+) infiltrations were assessed. In vitro, peritoneal macrophages (PMΦ) were isolated from wild-type and ß2AR-knockout female mice. The PMΦ were treated with ISO, E2, and ß2AR blocker ICI 118,551 for 24 h, and flow cytometric evaluations were done to assess their phenotypic expression. E2 deficiency permitted the induction of CSC, which was characterized by cardiac dysfunctions, maladaptive myocardial hypertrophy, unresolved proinflammatory responses, and fibrosis. Nonetheless, E2 presence/supplementation during stress averted all the aforementioned adverse effects of chronic stress while preventing excessive depletion of ß2AR. Also, we demonstrated that E2 facilitates timely resolution of myocardial proinflammation to permit reparative functions by enhancing the polarization of CD86+ to CD206+ macrophages. However, this adaptive immunomodulation is hampered when ß2AR is inhibited. Taken together, the outcomes of this study show that E2 confers cardioprotection to prevent CSC via adaptive immunomodulation of macrophage phenotypes, and ß2AR-mediated signaling is crucial for the polarizations of CD86+ to CD206+ macrophages.

19.
BMC Med Educ ; 21(1): 484, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34503514

RESUMO

BACKGROUND: The outbreak of COVID-19 has led to increased workload and infection risks among medical staff. This situation may influence current medical and health-related students' decision on the choices of their future careers. Hence, this study investigated the impact of COVID-19 on their future career intentions. METHODS: This is a cross-sectional observational study that included medical and health-related students from three universities between October 2020 and January 2021. The study questionnaire was divided into two main sections: Section 1, which comprised students' basic information. And section 2 focused mainly on the impact of COVID-19 pandemic on students' professional intentions. The chi-squared χ2 test was used to compare the responses before and after the pandemic outbreak among Chinese and non-Chinese students. RESULTS: In overall, 1253 students completed the questionnaires. The responses showed that the number of students who preferred clinical medicine, public health, pharmacy and oral medicine increased significantly after the pandemic outbreak. In contrast, the number of students who chose nursing and medical technology decreased significantly. The change mainly occurred in Chinese students, predominantly females. Half of students (50.35%) were more willing to engage in medical and health work after completing their current program. Also, 36.39% of students felt that knowledge was too limited in the pandemic's face and would like to continue studying after graduation to gain more knowledge. Due to the pandemic, 34.18% of students would like a future workplace near their hometown, and 19.63% preferred to work in urban areas. CONCLUSION: The COVID-19 outbreak impacted current medical and health-related students' career planning on their future workplaces and employment time choices. Additionally, the pandemic influenced the intention of Chinese students in choosing their future careers. This study provided the basis for the policymaking, specialty setting of colleges and supplied the medical health department's talent reserve information.


Assuntos
COVID-19 , Estudantes de Medicina , Estudos Transversais , Feminino , Humanos , Intenção , Masculino , Pandemias , SARS-CoV-2
20.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 37(8): 716-721, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34236031

RESUMO

Objective To explore the effects of Panax notoginseng saponins (PNS) on the proliferation, apoptosis, migration and invasion of osteosarcoma cell line U2OS and its possible molecular mechanism. Methods Human osteosarcoma cell line U2OS was cultured and treated with (0, 200, 400, 600, 800, 1000) µg/mL PNS. The proliferation of U2OS was detected by CCK-8 method. Annexin V-FITC/PI double labeling combined with flow cytometry was used to analyze cell apoptosis. Clone formation assay was used to detect the clone formation ability of the cells. TranswellTM invasion assay was performed to detect cell invasion. TranswellTM migration assay and wound-healing assay were used to determine cell migration. Western blotting was used to detect the expression of Notch1 and downstream protein Hes1 in U2OS cells. Results Compared with the control group, PNS could inhibit the proliferation of U2OS cells and the formation of clonal plaques, increase cell apoptosis rate, weaken the ability of migration and invasion and decrease the expression levels of Notch1 and Hes1 in the cells in a dose-dependent manner. Conclusion PNS can significantly inhibit the proliferation, migration and invasion and promote cell apoptosis of U2OS cells by blocking Notch1 signaling pathway.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Panax notoginseng , Saponinas , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Humanos , Osteossarcoma/tratamento farmacológico , Receptor Notch1/genética , Saponinas/farmacologia
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