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1.
Materials (Basel) ; 17(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38793381

RESUMO

In this work, thermomechanical treatment (single-pass rolling at 800 °C and solution treatment) was applied to nuclear-grade hot-rolled austenitic stainless steel to eliminate the mixed grain induced by the uneven hot-rolled microstructure. By employing high-temperature laser scanning confocal microscopy, microstructure evolution during solution treatment was observed in situ, and the effect of single-pass rolling reduction on it was investigated. In uneven hot-rolled microstructure, the millimeter-grade elongated grains (MEGs) possessed an extremely large size and a high Schmid factor for slip compared to the fine grains, which led to greater plastic deformation and increased dislocation density and deformation energy storage during single-pass rolling. During subsequent solution treatment, there were fewer nucleation sites for the new grain, and the grain boundary (GB) was the main nucleation site in MEGs at a lower rolling reduction. In contrast, at a higher reduction, increased uniformly distributed rolling deformation and more nucleation sites were developed in MEGs. As the reduction increased, the number of in-grain nucleation sites gradually exceeded that of GB nucleation sites, and in-grain nucleation preferentially occurred. This was beneficial for promoting the refinement of new recrystallized grains and a reduction in the size difference of new grains during recrystallization. The single-pass rolling reduction of 15-20% can effectively increase the nucleation sites and improve the uniformity of rolling deformation distribution in the MEGs, promote in-grain nucleation, and finally refine the abnormally coarse elongated grain, and eliminate the mixed-grain structure after solution treatment.

2.
Biosens Bioelectron ; 257: 116334, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38678788

RESUMO

Burkholderia pseudomallei, widely distributed in tropical and subtropical ecosystems, is capable of causing the fatal zoonotic disease melioidosis and exhibiting a global trend of dissemination. Rapid and sensitive detection of B. pseudomallei is essential for environmental monitoring as well as infection control. Here, we developed an innovative biosensor for quantitatively detecting B. pseudomallei relies on ATP released triggered by bacteriophage-induced bacteria lysis. The lytic bacteriophage vB_BpP_HN01, with high specificity, is employed alongside magnetic nanoparticles assembly to create a biological receptor, facilitating the capture and enrichment of viable target bacteria. Following a brief extraction and incubation process, the captured target undergoes rapid lysis to release contents including ATP. The EXPAR-CRISPR cascade reaction provides an efficient signal transduction and dual amplification module that allowing the generated ATP to guide the signal output as an activator, ultimately converting the target bacterial amount into a detectable fluorescence signal. The proposed bacteriophage affinity strategy exhibited superior performance for B. pseudomallei detection with a dynamic range from 10^2 to 10^7 CFU mL-1, and a LOD of 45 CFU mL-1 within 80 min. Moreover, with the output signal compatible across various monitoring methods, this work offers a robust assurance for rapid diagnosis and on-site environmental monitoring of B. pseudomallei.


Assuntos
Trifosfato de Adenosina , Bacteriófagos , Técnicas Biossensoriais , Burkholderia pseudomallei , Sistemas CRISPR-Cas , Burkholderia pseudomallei/virologia , Técnicas Biossensoriais/métodos , Bacteriófagos/química , Bacteriófagos/isolamento & purificação , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/análise , Melioidose/microbiologia , Limite de Detecção , Humanos , Nanopartículas de Magnetita/química
3.
Front Immunol ; 14: 1227041, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37662910

RESUMO

Retinoic acid-inducible gene-I (RIG-I) like receptor (RLR) pathway is one of the most significant pathways supervising aberrant RNA in cells. In predominant conditions, the RLR pathway initiates anti-infection function via activating inflammatory effects, while recently it is discovered to be involved in cancer development as well, acting as a virus-mimicry responder. On one hand, the product IFNs induces tumor elimination. On the other hand, the NF-κB pathway is activated which may lead to tumor progression. Emerging evidence demonstrates that a wide range of modifications are involved in regulating RLR pathways in cancer, which either boost tumor suppression effect or prompt tumor development. This review summarized current epigenetic modulations including DNA methylation, histone modification, and ncRNA interference, as well as post-transcriptional modification like m6A and A-to-I editing of the upstream ligand dsRNA in cancer cells. The post-translational modulations like phosphorylation and ubiquitylation of the pathway's key components were also discussed. Ultimately, we provided an overview of the current therapeutic strategies targeting the RLR pathway in cancers.


Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Fosforilação , Metilação de DNA , RNA de Cadeia Dupla , Tretinoína
4.
Nat Commun ; 14(1): 4839, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37563116

RESUMO

Persistent room temperature phosphorescent materials with unique mechanical properties and robust optical properties have great potential in flexible electronics and photonics. However, developing such materials remains a formidable challenge. Here, we present highly stretchable, lightweight, and multicolored persistent luminescence elastomers, produced by incorporating ionic room temperature phosphorescent polymers and polyvinyl alcohol into a polydimethylsiloxane matrix. These prepared elastomers exhibit high optical transparency in daylight and emit bright persistent luminescence after the removal of 365 nm excitation. The homogeneous distribution of polymers within the matrix has been confirmed by confocal fluorescence microscopy, scanning electron microscopy, and atomic force microscopy. Mechanical property investigations revealed that the prepared persistent luminescence elastomers possess satisfactory stretchability. Impressively, these elastomers maintain robust optical properties even under extensive and repeated mechanical deformations, a characteristic previously unprecedented. These fantastic features make these persistent luminescence elastomers ideal candidates for potential applications in wearable devices, flexible displays, and anti-counterfeiting.

5.
Nat Commun ; 14(1): 627, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36746937

RESUMO

Organic room-temperature phosphorescent (RTP) materials exhibiting reversible changes in optical properties upon exposure to external stimuli have shown great potential in diverse optoelectronic fields. Particularly, dynamic manipulation of response behaviors for such materials is of fundamental significance, but it remains a formidable challenge. Herein, a series of RTP polymers were prepared by incorporating phosphorescent rotors into polymer backbone, and these materials show color-tunable persistent luminescence upon excitation at different wavelengths. Experimental results and theoretical calculations revealed that the various molecular conformations of monomers are responsible for the excitation wavelength-dependent (Ex-De) RTP behavior. Impressively, after gaining insights into the underlying mechanism, dynamic control of Ex-De RTP behavior was achieved through thermal energy driven molecular rotations of monomers. Eventually, we demonstrate the practical applications of these amorphous polymers in anti-counterfeiting areas. These findings open new opportunities for the control of response behaviors of smart-responsive RTP materials through external stimuli rather than conventional covalent modification method.

6.
Angew Chem Int Ed Engl ; 61(27): e202202655, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35460581

RESUMO

Repeatable printing of invisible multicolor luminescence patterns with long retention times on transparent substrates is of significant importance, but it remains a formidable challenge. Here, two novel hydrazone-based on/off fluorescent photoswitches with decent emission quantum efficiencies, good reversible photoisomerization properties, and extremely long thermal half-lives, were designed and synthesized. Excitingly, X-ray crystallography data of both Z and E isomers of one hydrazone-based photoswitch were obtained. Multiple emission colors of blue, cyan, green, yellow, and orange can be obtained readily for these two photoswitches upon coordination with various zinc salts. Moreover, the photo-controlled rewritable printing of invisible multicolor images with high resolution was achieved by using these photoswitches. Importantly, the legibility of the printed patterns can last at least over 3 months without detectable emission intensity loss under ambient conditions.

7.
J Health Econ ; 80: 102548, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34763199

RESUMO

The capitated payment model has been used to address the high cost of health care. Under capitation, physicians are compensated with a fixed amount per patient, regardless of the services generated. We provide new evidence on how the capitation payment model changes physicians behaviors by studying the treatment of lower back pain, as this type of treatment provides substantial scope for physicians discretion. We use data from 2003 to 2006 from a large database of employer-sponsored health insurance claims and leverage capitation variation within the plan and physician to mitigate selection concerns. The results show that the treatment intensity-primarily derived from therapy and diagnostic testing -of patients under a capitation system is 7-12% lower than that of similar patients in a non-capitated plan. Furthermore, we find no evidence of increased relapse rates for patients in a capitated plan.


Assuntos
Dor Lombar , Médicos , Capitação , Humanos , Dor Lombar/terapia
8.
Nanomaterials (Basel) ; 9(7)2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31373284

RESUMO

Nickel phyllosilicates have attracted much attention owing to their potential applications in various fields. Herein, Ni3Si4O10(OH)2 porous microspheres (NiSi-PMs) with a diameter of 1.2 to 3.2 µm were successfully fabricated via a urea-assisted hydrothermal method, and subsequently used to prepare supported Pd catalyst. Characterizations of the NiSi-PMs and the obtained catalyst, combined with the catalytic performance for the hydrogenation reaction, are presented and discussed. The BET surface area and pore volume of the NiSi-PMs were 196.2 m2 g-1 and 0.70 cm3 g-1, respectively. The Pd/NiSi-PMs catalyst exhibited remarkable catalytic activity for the hydrogenation of styrene under mild conditions, with a turnover frequency of 5234 h-1, and the catalyst was recovered and recycled for six consecutive cycles without any discernible loss of activity. H2-TPR and H2-TPD revealed that the activity of the catalysts was closely related to the adsorption property for hydrogen. The present Ni3Si4O10(OH)2 supported Pd catalyst afforded a promising and competitive candidate for heterogeneous catalysis.

9.
Comb Chem High Throughput Screen ; 22(3): 194-200, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30973105

RESUMO

BACKGROUND: Chinese herbal monomer hairy Calycosin is a flavonoid extracted from Radix astragali. Aims and Scope: The aim of the research was to investigate the effect and mechanism of Hairy Calycosin on Non-Alcoholic Fatty Liver Dieases (NAFLD) in rats. MATERIALS AND METHODS: 60 rats were randomly divided into 6 groups, then NAFLD rat models were prepared and treated with different doses of Hairy Calycosin (0.5, 1.0, 2.0 mg/kg) or Kathyle relatively. RESULTS: Both 1.0 mg/kg and 2.0 mg/kg Hairy Calycosin treatment could significantly increase the serum Superoxide Dismutase (SOD) content of the model rats and reduce the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), Free Fatty Acid (FFA), IL-6, tumor necrosis factor-alpha (TNF-α) and liver homogenate malondialdehyde (MDA), while 2.0 mg/kg Hairy Calycosin can down-regulate liver tissue cytochrome p450 2E1 (CYP2E1). In the electron microscope, compared with the model control group, the mitochondrial swelling in the hepatocytes of Hairy Calycosin (1.0, 2.0 mg/kg) treatment group was significantly reduced, the ridge on the inner membrane of mitochondria increased, and the lipid droplets became much smaller. CONCLUSION: Hairy Calycosin can effectively control the lipid peroxidation in liver tissues of rats with NAFLD, and reduce the levels of serum TNF-α, IL-6, MDA and FFA, effectively improve the steatosis and inflammation of liver tissue, and down-regulate the expression of CYP2E1, inhibit apoptosis of hepatocytes.


Assuntos
Medicamentos de Ervas Chinesas/química , Isoflavonas/química , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Astragalus propinquus , Citocromo P-450 CYP2E1/metabolismo , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Ácidos Graxos não Esterificados/metabolismo , Hepatócitos/metabolismo , Interleucina-6/metabolismo , Isoflavonas/farmacologia , Masculino , Malondialdeído/metabolismo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
10.
Kaohsiung J Med Sci ; 23(6): 313-7, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17525017

RESUMO

A variety of coronary artery disorders, including intramyocardial coronary segments and coronary artery anomalies, can result in sudden cardiac death, especially in young adults. The detection of structural coronary artery abnormalities is important in the management of patients at risk of sudden cardiac death. Coronary artery anomalies occur in about 1% of the population. Congenital absence of left circumflex coronary artery (LCX) is a very rare vascular anomaly, and few cases have been reported in the literature, with a frequency of only 0.003% in all patients who underwent coronary angiography. Although coronary catheterization is the gold standard for the evaluation of coronary arterial patency disease, noninvasive computed tomography (CT) is considered the diagnostic method of choice for the detection and evaluation of coronary artery anomaly. Herein, we report the case of a 17-year-old girl who presented with exertional dyspnea and chest pain and who was studied at our emergency department with the final diagnosis of LCX atresia detected by 64-slice CT. She may be the first case of congenital LCX atresia proved by multislice CT.


Assuntos
Anomalias dos Vasos Coronários/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Feminino , Humanos
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