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1.
Opt Lett ; 48(7): 1894-1897, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221793

RESUMO

In this Letter, we present a method aiming at background noise removal in the 3D reconstruction of light field microscopy (LFM). Sparsity and Hessian regularization are taken as two prior knowledges to process the original light field image before 3D deconvolution. Due to the noise suppression function of total variation (TV) regularization, we add the TV regularization term to the 3D Richardson-Lucy (RL) deconvolution. By comparing the light field reconstruction results of our method with another state-of-the-art method that is also based on RL deconvolution, the proposed method shows improved performance in terms of removing background noise and detail enhancement. This method will be beneficial to the application of LFM in biological high-quality imaging.

2.
Cell Biol Toxicol ; 39(5): 2033-2050, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-35038059

RESUMO

Multiple myeloma (MM) is a pernicious plasma cell disorder and has a poor prognosis. N6-methyladenosine (m6A) is an abundant epigenetic RNA modification and is important in cancer progression. Nevertheless, the function of m6A and its regulator METTL3 in MM are rarely reported. Here, we identified the m6A "writers", METTL3, was enhanced in MM and found that Yin Yang 1 (YY1) and primary-miR-27a-3p were the potential target for METTL3. METTL3 promoted primary-miR-27a-3p maturation and YY1 mRNA stability in an m6A manner. YY1 also was found to facilitate miR-27a-3p transcription. METTL3 affected the growth, apoptosis, and stemness of MM cells through accelerating the stability of YY1 mRNA and the maturation of primary-miR-27a-3p in vitro and in vivo. Our results reveal the key function of the METTL3/YY1/miR-27a-3p axis in MM and may provide fresh insights into MM therapy.


Assuntos
Metiltransferases , MicroRNAs , Mieloma Múltiplo , Fator de Transcrição YY1 , Humanos , Carcinogênese , Transformação Celular Neoplásica , Metiltransferases/genética , Metiltransferases/metabolismo , MicroRNAs/genética , Mieloma Múltiplo/genética , Fator de Transcrição YY1/genética , Fator de Transcrição YY1/metabolismo
3.
J Med Internet Res ; 25: e39507, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36857115

RESUMO

BACKGROUND: Patients with high myopia have an increased lifetime risk of complications. The prevalence patterns of high myopia in children and adolescents in southern China are unclear. Early identification of high-risk individuals is critical for reducing the occurrence and development of high myopia and avoiding the resulting complications. OBJECTIVE: This study aimed to determine the prevalence of high myopia in children and adolescents in southern China via real-world screening data and to predict its onset by studying the risk factors for high myopia based on machine learning. METHODS: This retrospective school-based study was conducted in 13 cities with different gross domestic products in southern China. Through data acquisition and filtering, we analyzed the prevalence of high myopia and its association with age, school stage, gross domestic product, and risk factors. A random forest algorithm was used to predict high myopia among schoolchildren and then assessed in an independent hold-out group. RESULTS: There were 1,285,609 participants (mean age 11.80, SD 3.07, range 6-20 years), of whom 658,516 (51.2%) were male. The overall prevalence of high myopia was 4.48% (2019), 4.88% (2020), and 3.17% (2021), with an increasing trend from the age of 11 to 17 years. The rates of high myopia increased from elementary schools to high schools but decreased at all school stages from 2019 to 2021. The coastal and southern cities had a higher proportion of high myopia, with an overall prevalence between 2.60% and 5.83%. Age, uncorrected distance visual acuity, and spherical equivalents were predictive factors for high myopia onset in schoolchildren. The random forest algorithm achieved a high accuracy of 0.948. The area under the receiver operator characteristic curve (AUC) was 0.975. Both indicated sufficient model efficacy. The performance of the model was validated in an external test with high accuracy (0.971) and a high AUC (0.957). CONCLUSIONS: High myopia had a high incidence in Guangdong Province. Its onset in children and adolescents was well predicted with the random forest algorithm. Efficient use of real-world data can contribute to the prevention and early diagnosis of high myopia.


Assuntos
Miopia , Humanos , Adolescente , Criança , Masculino , Adulto Jovem , Adulto , Feminino , Prevalência , Estudos Retrospectivos , China , Cidades
4.
Anal Chem ; 92(9): 6631-6636, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32272833

RESUMO

Lipid droplets (LDs) are closely connected to many physiological processes and abnormal LDs are related to many diseases. Herein, a family of two-photon fluorescence compounds based on the aurone skeleton were developed as efficient LDs imaging probes. They exhibit the obvious solvatochromism effect from blue to orange emission (∼140 nm shift) in various solvents. The robust probes possess low toxicity to living cells, high photobleaching resistance, and superior photostability and can light up LDs with high specificity. Furthermore, the probe DMMB (aurone skeleton with dimethylamino) was carefully applied in real-time monitoring of the morphological changes of LDs and the interactions between LDs and mitochondria under specific physiological conditions (e.g., starvation). We have observed for the first time the dynamic change between mitochondria and LDs when mitochondrial damage is caused by a large excess of H2O2 in a short period of time.


Assuntos
Benzofuranos/metabolismo , Gotículas Lipídicas/metabolismo , Sondas Moleculares/metabolismo , Benzofuranos/química , Sobrevivência Celular/efeitos dos fármacos , Humanos , Gotículas Lipídicas/química , Sondas Moleculares/química , Sondas Moleculares/farmacologia , Estrutura Molecular , Ácido Oleico/análise , Imagem Óptica , Estresse Oxidativo , Células Tumorais Cultivadas
5.
J Agric Food Chem ; 72(21): 11958-11967, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38761134

RESUMO

Megalurothrips usitatus (Bagnall), the main pest on legume vegetables, is controlled by pyrethroids in the field. Field strains of M. usitatus resistant to pyrethroids were collected from three areas in Hainan Province (Haikou, Ledong, and Sanya City), and two mutations, T929I and K1774N, were detected in the voltage-gated sodium channel. In this study, the sodium channel in M. usitatus was first subcloned and successfully expressed in Xenopus oocytes. The single mutation (T929I or K1774N) and double mutation (T929I/K1774N) shifted the voltage dependence of activation in the hyperpolarization direction. The three mutants all reduced the amplitude of tail currents induced by type I (permethrin and bifenthrin) and type II (deltamethrin and λ-cyhalothrin) pyrethroids. Homology modeling analysis of these two mutations shows that they may change the local hydrophobicity and positive charge of the sodium channel. Our data can be used to reveal the causes of the resistance of M. usitatus to pyrethroids and provide guidance for the comprehensive control of M. usitatus in the future.


Assuntos
Proteínas de Insetos , Resistência a Inseticidas , Inseticidas , Mutação , Piretrinas , Canais de Sódio Disparados por Voltagem , Piretrinas/farmacologia , Animais , Canais de Sódio Disparados por Voltagem/genética , Canais de Sódio Disparados por Voltagem/química , Canais de Sódio Disparados por Voltagem/metabolismo , Inseticidas/farmacologia , Inseticidas/química , Resistência a Inseticidas/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/química , Mariposas/genética , Mariposas/efeitos dos fármacos
6.
Toxicol In Vitro ; 100: 105919, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39154867

RESUMO

Isobavachin (IBA) is a dihydroflavonoid compound with various pharmacological effects. However, further investigation into the hepatotoxicity of IBA is necessary. This study aims to identify the hepatotoxic effects of IBA and explore its potential mechanisms. The study assessed the impact of IBA on the viability of AML12, HepG2, LO2, rat, and mouse primary hepatocytes using MTT and LDH assays. Autophagy was detected in AML12 cells after IBA treatment using electron microscopy, MDC, and Ad-mCherry-GFP-LC3B fluorescence. The effect of IBA on autophagy-related proteins was examined using Western blot. The results showed that IBA had dose-dependent inhibitory effects on five cells, induced autophagy in AML12 cells, and promoted autophagic flux. The study found that IBA treatment inhibited phosphorylation of PI3K, Akt, and mTOR, while increasing phosphorylation levels of AMPK and ULK1. Treatment with both AMPK and PI3K inhibitors reversed the expression of AMPK and PI3K-Akt-mTOR signaling pathway proteins. These results suggest that IBA may have hepatocytotoxic effects but can also prevent IBA hepatotoxicity by inhibiting the AMPK and PI3K/Akt/mTOR signaling pathways. This provides a theoretical basis for preventing and treating IBA hepatotoxicity in clinical settings.

7.
Environ Sci Pollut Res Int ; 30(12): 32614-32627, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36469266

RESUMO

Both the realization of the "double carbon" goal and the low-carbon economy development requires a focus on transportation CO2 emissions. Calculating Chinese transportation CO2 emissions and exploring its principles are essential for achieving high-quality development of the transportation industry. Firstly, we use a "top-down" method to assess carbon emissions from transportation operations from 2003 to 2019. Secondly, the study decomposes the influencing factors of transportation CO2 emissions in China using the log-average weight decomposition method. Thirdly, the Tapio decoupling model is applied to study the decoupling effect of transportation CO2 emissions in each province of China. The findings suggest that China's transport carbon emissions are growing at an annual rate of roughly 16%. All GDP per capita, transportation energy intensity, and population size increase the growth of transportation CO2 emissions. Contrastly, energy use per unit of turnover and transportation intensity decrease the growth of transportation CO2 emissions. There is much variation in China's carbon emission decoupling index from year to year. Policy recommendations are proposed in response to the study of the above findings and the differences in carbon reduction potential among provinces.


Assuntos
Dióxido de Carbono , Emissões de Veículos , Dióxido de Carbono/análise , China , Desenvolvimento Econômico , Carbono/análise , Meios de Transporte
8.
J Agric Food Chem ; 71(6): 2734-2744, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36701428

RESUMO

The effectiveness of pyrethroid insecticides is seriously threatened by knockdown resistance (kdr), which is induced in insects by inherited single-nucleotide polymorphisms in the voltage-gated sodium channel (VGSC) gene. VGSC's L1014F substitution results in the classic kdr mutation, which is found in many pest species. Other substitutions of the L1014 locus, such as L1014S, L1014C, L1014W, and L1014H, were also reported. In 2022, a new amino acid substitute L1014S of Blattella germanica was first discovered in China. We modified the BgNav1-1 sodium channel from cockroaches with the L1014S mutation to study how pyrethroid sensitivity and channel gating were affected in Xenopus oocytes. The L1014S mutation reduced the half-maximal activation voltage (V1/2,act) from -19.0 (wild type) to -15.5 mV while maintaining the voltage dependency of activation. Moreover, the voltage dependence of inactivation in the hyperpolarizing shifts from -48.3 (wild type) to -50.9 mV. However, compared with wild type, the mutation L1014S did not cause a significant shift in the half activation voltage (V1/2,act). Notably, the voltage dependency of activation was unaffected greatly by the L1014S mutation. Tail currents are induced by two types of pyrethroids (1 µM): type I (permethrin, bifenthrin) and type II (deltamethrin, λ-cyhalothrin). All four pyrethroids produced tail currents, and significant differences were found in the percentages of channel modifications between variants and wild types. Further computer modeling showed that the L1014S mutation allosterically modifies pyrethroid binding and action on B. germanica VGSC, with some residues playing a critical role in pyrethroid binding. This study elucidated the pyrethroid resistance mechanism of B. germanica and predicted the residues that may confer the risk of pyrethroid resistance, providing a molecular basis for understanding the resistance mechanisms conferred by mutations at the 1014 site in VGSC.


Assuntos
Blattellidae , Inseticidas , Piretrinas , Animais , Inseticidas/farmacologia , Blattellidae/genética , Resistência a Inseticidas/genética , Piretrinas/farmacologia , Mutação
9.
New Microbes New Infect ; 52: 101102, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36815201

RESUMO

Mpox (Monkeypox) is a zoonotic disease caused by mpox virus (MPXV). A multi-country MPXV outbreak in non-endemic demographics was identified in May 2022. A systematic evaluation of MPXV evolutionary trajectory and genetic diversity could be a timely addition to the MPXV diagnostics and prophylaxis. Herein, we integrated a systematic evolution analysis including phylogenomic and phylogeographic, followed by an in-depth analysis of the adaptive evolution and amino acid variations in type I interferon binding protein (IFNα/ßBP). Mutations in IFNα/ßBP protein may impair its binding capacity, affecting the MPXV immune evasion strategy. Based on the equilibrated data, we found an evolutionary rate of 7.75 × 10 - 5 substitutions/site/year, and an earlier original time (2021.25) of the clade IIb. We further discovered significant genetic variations in MPXV genomes from different regions and obtained six plausible spread trajectories from its intricate viral flow network, implying that North America might have acted as a bridge for the spread of MPXV from Africa to other continents. We identified two amino acids under positive selection in the Rifampicin resistance protein and extracellular enveloped virus (EEV) type-I membrane glycoprotein, indicating a role in adaptive evolution. Our research sheds light on the emergence, dispersal, and adaptive evolution of MPXV, providing theoretical support for mitigating and containing its expansion.

10.
Polymers (Basel) ; 14(16)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36015633

RESUMO

Biodegradable polymeric materials have become the most attractive research interest in recent years and are gradually widely used in various fields in the case of environmental pollution. In this paper, binary blends, mainly including varying contents of polyglycolic acid (PGA) and poly(vinyl alcohol) (PVA), were prepared via a melt compounding strategy. The ethylene-methyl acrylate-glycidyl methacrylate (EMA-GMA) was employed as the compatibilizer to improve the compatibility between the PGA and PVA and the polyolefin elastomer (POE) was used as toughening agent. The anti-compression property and water-soluble ability of the blends were particularly studied to explore their potential application in an oil/gas exploitation field. Special attentions were paid to the evolution of the water-soluble ability of PGAX with the PVA concentration. Furthermore, isothermal shear measurement and thermogravimetric analysis were performed to evaluate the thermal stability of PGA and PGA blends (PGAX) during melt processing. The results showed that the incompatibility between PGA and PVA largely deteriorated the mechanical property, i.e., anti-compression strength, leading to fragile characteristics under a lower compressive load for the PGAX samples with varied contents of PVA. The presence of PVA and EMA-GMA greatly enhanced the viscoelasticity of the PGA melt, showing an increased storage modulus and viscosity at a low shear frequency; however, the thermal instability of PGAX was intensified owing to the greater ease of thermal degradation of PVA than that of PGA. Meanwhile, the water-soluble ability of PGAX was improved due to the high water dissolution of PVA, which played the role as a sacrificial material. The purpose of this work is to pursue an effective modification for PGA processing and application via melt blending.

11.
Materials (Basel) ; 14(23)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34885303

RESUMO

Supercapacitors have the unique advantages of high power density, fast charge and discharge rates, long cycle life, high safety, and reliability, and are increasingly being used for applications including automobiles, rail transit, communication equipment, digital electronics, and aerospace equipment. The supercapacitor industry is currently in a stage of rapid development; great breakthroughs have also been made in improving the performance of supercapacitors and the expansion of their application. Electrode technology is the core of supercapacitors. Transition-metal compounds have a relatively high theoretical capacity and have received widespread attention as electrode materials for supercapacitors. In addition, there is a synergistic effect between the different components of various electrode composite materials. Due to their superior electrochemical performance, supercapacitors are receiving increasing research attention. Flexible supercapacitors have been hailed for their good plasticity, resulting in a development boom. This review article mainly outlines the development process of various electrode materials, including carbon materials, conductive polymers, metal compounds, and composite materials, as well as flexible electrode materials based on carbon cloth.

12.
Eur J Pharmacol ; 891: 173752, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33253679

RESUMO

The overall survival of multiple myeloma (MM) patients significantly improved with the use of proteasome inhibitor such as bortezomib. However, resistance to sorafenib limits its use. Bortezomib-resistant MM cells were generated and their bortezomib-resistant properties were confirmed by cell viability and apoptosis assays. To explore functions and underlying mechanisms of long non-coding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) on bortezomib resistance in MM, MTT assays, flow cytometry analyses, dual luciferase report gene assays, RNA pulldown assays and chromatin immunoprecipitation assays were carried out. NEAT1 and specific protein 1 (Sp1) was upregulated while miR-29b-3p was down regulated in bortezomib-resistant MM cells. NEAT1 promoted Sp1 expression by sponging miR-29b-3p and then enhanced the tolerance of MM cells to bortezomib. Sp1 targeted to NEAT1 promoter region promoting NEAT1 transcription and formed a positive feedback loop. NEAT1 and Sp1 levels were higher and miR-29b-3p was levels were lower in bortezomib-resistant MM patients. NEAT1/miR-29b-3p/Sp1 feedback loop enhanced the tolerance of MM cells to bortezomib. These results indicate potentially valuable targets for overcoming bortezomib resistance for MM.


Assuntos
Antineoplásicos/farmacologia , Bortezomib/farmacologia , Resistencia a Medicamentos Antineoplásicos , MicroRNAs/metabolismo , Mieloma Múltiplo/tratamento farmacológico , Inibidores de Proteassoma/farmacologia , RNA Longo não Codificante/metabolismo , Fator de Transcrição Sp1/metabolismo , Estudos de Casos e Controles , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Retroalimentação Fisiológica , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , RNA Longo não Codificante/genética , Fator de Transcrição Sp1/genética
13.
Chem Commun (Camb) ; 55(99): 14980-14983, 2019 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-31777874

RESUMO

A ratiometric fluorescent probe for hydrazine based on a coumarin chalcone framework and a levulinic acid terminal group with a low detection limit (0.1 ppb, 0.003 µM), a large ratiometric fluorescence change (I465/I575, 1265-fold enhancement) and a wide pH work range (3.0-12.0) was developed. The mechanism analysis of the isolated hydrazine product characterized by NMR, HRMS and the crystal structure indicates that the levulinic acid group is firstly removed by deprotection and then the dihydropyrazole ring is formed due to the addition and subsequent cyclization reaction in the presence of hydrazine.

14.
J Agric Food Chem ; 64(3): 706-13, 2016 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-26746696

RESUMO

As one of most common synthetic phenolic antioxidants, tertiary butylhydroquinone (TBHQ) has received increasing attention due to the potential risk for liver damage and carcinogenesis. Herein, a simple and rapid fluorescent switchable methodology was developed for highly selective and sensitive determination of TBHQ by utilizing the competitive interaction between the photoinduced electron transfer (PET) effect of carbon dots (CDs)/Fe(III) ions and the complexation reaction of TBHQ/Fe(III) ions. This novel fluorescent switchable sensing platform allows determining TBHQ in a wider range from 0.5 to 80 µg mL(-1) with a low detection limit of 0.01 µg mL(-1). Furthermore, high specificity and good accuracy with recoveries ranging from 94.29 to 105.82% in spiked edible oil samples are obtained with the present method, confirming its applicability for the trace detection of TBHQ in a complex food matrix. Thus, the present method provides a novel and effective fluorescent approach for rapid and specific screening of TBHQ in common products, which is beneficial for monitoring and reducing the risk of TBHQ overuse during food storage.


Assuntos
Hidroquinonas/química , Óleos de Plantas/química , Espectrometria de Fluorescência/métodos , Hidroxianisol Butilado , Fluorescência , Sensibilidade e Especificidade
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