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1.
PLoS Pathog ; 20(2): e1011999, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38306394

RESUMO

Hepatitis B virus (HBV) chronically infects 296 million people worldwide, posing a major global health threat. Export of HBV RNAs from the nucleus to the cytoplasm is indispensable for viral protein translation and genome replication, however the mechanisms regulating this critical process remain largely elusive. Here, we identify a key host factor embryonic lethal, abnormal vision, Drosophila-like 1 (ELAVL1) that binds HBV RNAs and controls their nuclear export. Using an unbiased quantitative proteomics screen, we demonstrate direct binding of ELAVL1 to the HBV pregenomic RNA (pgRNA). ELAVL1 knockdown inhibits HBV RNAs posttranscriptional regulation and suppresses viral replication. Further mechanistic studies reveal ELAVL1 recruits the nuclear export receptor CRM1 through ANP32A and ANP32B to transport HBV RNAs to the cytoplasm via specific AU-rich elements, which can be targeted by a compound CMLD-2. Moreover, ELAVL1 protects HBV RNAs from DIS3+RRP6+ RNA exosome mediated nuclear RNA degradation. Notably, we find HBV core protein is dispensable for HBV RNA-CRM1 interaction and nuclear export. Our results unveil ELAVL1 as a crucial host factor that regulates HBV RNAs stability and trafficking. By orchestrating viral RNA nuclear export, ELAVL1 is indispensable for the HBV life cycle. Our study highlights a virus-host interaction that may be exploited as a new therapeutic target against chronic hepatitis B.


Assuntos
Vírus da Hepatite B , RNA Viral , Animais , Humanos , Vírus da Hepatite B/metabolismo , Transporte Ativo do Núcleo Celular , RNA Viral/genética , RNA Viral/metabolismo , Drosophila/genética , Replicação Viral/genética , Proteínas Nucleares/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteína Semelhante a ELAV 1/genética , Proteína Semelhante a ELAV 1/metabolismo
2.
PLoS Pathog ; 19(5): e1011382, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37224147

RESUMO

Hepatitis B virus (HBV) chronically infects 296 million individuals and there is no cure. As an important step of viral life cycle, the mechanisms of HBV egress remain poorly elucidated. With proteomic approach to identify capsid protein (HBc) associated host factors and siRNA screen, we uncovered tumor susceptibility gene 101 (TSG101). Knockdown of TSG101 in HBV-producing cells, HBV-infected cells and HBV transgenic mice suppressed HBV release. Co-immunoprecipitation and site mutagenesis revealed that VFND motif in TSG101 and Lys-96 ubiquitination in HBc were essential for TSG101-HBc interaction. In vitro ubiquitination experiment demonstrated that UbcH6 and NEDD4 were potential E2 ubiquitin-conjugating enzyme and E3 ligase that catalyzed HBc ubiquitination, respectively. PPAY motif in HBc and Cys-867 in NEDD4 were required for HBc ubiquitination, TSG101-HBc interaction and HBV egress. Transmission electron microscopy confirmed that TSG101 or NEDD4 knockdown reduces HBV particles count in multivesicular bodies (MVBs). Our work indicates that TSG101 recognition for NEDD4 ubiquitylated HBc is critical for MVBs mediated HBV egress.


Assuntos
Vírus da Hepatite B , Proteômica , Animais , Camundongos , Vírus da Hepatite B/genética , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/genética , Camundongos Transgênicos
3.
Eur Radiol ; 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39060495

RESUMO

OBJECTIVES: The Alberta Stroke Program Early CT Score (ASPECTS), a systematic method for assessing ischemic changes in acute ischemic stroke using non-contrast computed tomography (NCCT), is often interpreted relying on expert experience and can vary between readers. This study aimed to develop a clinically applicable automatic ASPECTS system employing deep learning (DL). METHODS: This study enrolled 1987 NCCT scans that were retrospectively collected from four centers between January 2017 and October 2021. A DL-based system for automated ASPECTS assessment was trained on a development cohort (N = 1767) and validated on an independent test cohort (N = 220). The consensus of experienced physicians was regarded as a reference standard. The validity and reliability of the proposed system were assessed against physicians' readings. A real-world prospective application study with 13,399 patients was used for system validation in clinical contexts. RESULTS: The DL-based system achieved an area under the receiver operating characteristic curve (AUC) of 84.97% and an intraclass correlation coefficient (ICC) of 0.84 for overall-level analysis on the test cohort. The system's diagnostic sensitivity was 94.61% for patients with dichotomized ASPECTS at a threshold of ≥ 6, with substantial agreement (ICC = 0.65) with expert ratings. Combining the system with physicians improved AUC from 67.43 to 89.76%, reducing diagnosis time from 130.6 ± 66.3 s to 33.3 ± 8.3 s (p < 0.001). During the application in clinical contexts, 94.0% (12,591) of scans successfully processed by the system were utilized by clinicians, and 96% of physicians acknowledged significant improvement in work efficiency. CONCLUSION: The proposed DL-based system could accurately and rapidly determine ASPECTS, which might facilitate clinical workflow for early intervention. CLINICAL RELEVANCE STATEMENT: The deep learning-based automated ASPECTS evaluation system can accurately and rapidly determine ASPECTS for early intervention in clinical workflows, reducing processing time for physicians by 74.8%, but still requires validation by physicians when in clinical applications. KEY POINTS: The deep learning-based system for ASPECTS quantification has been shown to be non-inferior to expert-rated ASPECTS. This system improved the consistency of ASPECTS evaluation and reduced processing time to 33.3 seconds per scan. 94.0% of scans successfully processed by the system were utilized by clinicians during the prospective clinical application.

4.
Soft Matter ; 20(26): 5212-5220, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38904173

RESUMO

Understanding how particles pack in space and the mechanisms underlying symmetry selection across soft matter is challenging. The Frank-Kasper (F-K) phase of complex spherical packing is amongst the most fascinating phases; however, it has not been observed in discotic liquid crystals until now. Herein, we report the first observation of F-K phases of charge transfer complexes (CTCs) obtained from triphenylene derivatives as donors and 2,4,7-trinitro-9-fluorenone as the acceptor. The CTCs were characterized using experimental and theoretical calculations, indicating that the F-K A15 cubic lattice possesses a unit cell containing 8 sphere-like supramolecules, each of which was self-assembled from 3 CTC complexes. The lattice constant was only 3.2 nm, which is by far the smallest for the A15 phase. Interestingly, the supramolecular assembly can be regarded as the molecular column splitting into isolated spherical fragments, impeding charge transfer and turning it into one insulator. This provides a simple and effective method for preparing asymmetric complex compounds for the design of unconventional self-assembled nanostructures.

5.
Inorg Chem ; 63(22): 10108-10113, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38771149

RESUMO

Metal-organic cages (MOCs) with luminophores have significant advantages for the facile detection of specific molecules based on turn-on or turn-off luminescence changes induced by host-guest complexation. One important challenge is the development of turn-on-type near-infrared (NIR)-luminescent MOCs. In this study, we synthesized a novel MOC consisting of two porphyrin dyes linked by four Yb(III) complexes, which exhibit bimodal red and NIR fluorescence signals upon photoexcitation of the porphyrin π system. Single-crystal X-ray structural analysis and computational molecular modeling revealed that planar aromatic perfluorocarbons were intercalated into the MOC. The tight packing between the MOC and guests enhanced the NIR fluorescence of Yb(III) by suppressing energy transfer from the photoexcited porphyrin to oxygen molecules. Guest-responsive turn-on NIR fluorescence changes in an MOC were successfully demonstrated.

6.
Phytother Res ; 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39120474

RESUMO

Calycosin (Caly), a flavonoid compound, demonstrates a variety of beneficial properties. However, the specific mechanisms behind Caly's anticancer effects remain largely unexplored. Network pharmacology was used to explore the potential targets of Caly in renal cancer. Additionally, RNA-seq sequencing was used to detect changes in genes in renal cancer cells after Caly treatment. Validation was carried out through quantitative reverse transcription-PCR and Western blot analysis. The luciferase reporter assay was applied to pinpoint the interaction site between MAZ and HAS2. Furthermore, the immunoprecipitation assay was utilized to examine the ubiquitination and degradation of MAZ. In vivo experiments using cell line-derived xenograft mouse models were performed to assess Calycosin's impact on cancer growth. Network pharmacology research suggests Caly plays a role in promoting apoptosis and inhibiting cell adhesion in renal cancer. In vitro, Caly has been observed to suppress proliferation, colony formation, and metastasis of renal cancer cells while also triggering apoptosis. Additionally, it appears to diminish hyaluronic acid synthesis by downregulating HAS2 expression. MAZ is identified as a transcriptional regulator of HAS2 expression. Calycosin further facilitates the degradation of MAZ via the ubiquitin-proteasome pathway. Notably, Caly demonstrates efficacy in reducing the growth of renal cell carcinoma xenograft tumors in vivo. Our findings indicate that Caly suppresses the proliferation, metastasis, and progression of renal cell carcinoma through its action on the MAZ/HAS2 signaling pathway. Thus, Caly represents a promising therapeutic candidate for the treatment of renal cell carcinoma.

7.
Sensors (Basel) ; 24(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38610529

RESUMO

Intelligent vehicle trajectory tracking exhibits problems such as low adaptability, low tracking accuracy, and poor robustness in complex driving environments with uncertain road conditions. Therefore, an improved method of adaptive model predictive control (AMPC) for trajectory tracking was designed in this study to increase the corresponding tracking accuracy and driving stability of intelligent vehicles under uncertain and complex working conditions. First, based on the unscented Kalman filter, longitudinal speed, yaw speed, and lateral acceleration were considered as the observed variables of the measurement equation to estimate the lateral force of the front and rear tires accurately in real time. Subsequently, an adaptive correction estimation strategy for tire cornering stiffness was designed, an AMPC method was established, and a dynamic prediction time-domain adaptive model was constructed for optimization according to vehicle speed and road adhesion conditions. The improved AMPC method for trajectory tracking was then realized. Finally, the control effectiveness and trajectory tracking accuracy of the proposed AMPC technique were verified via co-simulation using CarSim and MATLAB/Simulink. From the results, a low lateral position error and heading angle error in trajectory tracking were obtained under different vehicle driving conditions and road adhesion conditions, producing high trajectory-tracking control accuracy. Thus, this work provides an important reference for improving the adaptability, robustness, and optimization of intelligent vehicle tracking control systems.

8.
Zhongguo Zhong Yao Za Zhi ; 49(7): 1924-1931, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38812205

RESUMO

The Chinese medical mechanism of Huanglian Jieduo Decoction on treating Alzheimer's disease(AD) characterized by "toxin damaging brain collateral" is still unclear. This study aims to explore the mechanism of Huanglian Jieduo Decoction on regulating triggering receptor expressed on myeloid cells 2(TREM2)/protein kinase B(Akt)/glycogen synthase kinase 3ß(GSK3ß) pathway to improve the cognitive deficit in APP/PS1 transgenic mice. APP/PS1 mice of approximately nine months old were randomly divided into the model group, the low, medium, and high(2.5, 5, and 10 g·kg~(-1)) groups of Huanglian Jiedu Decoction, and 0.75 mg·kg~(-1) donepezil hydrochloride group, and the C57BL/6J mice with the same age were taken as the normal group. After one month of continuous oral administration, a Morris water maze was performed to detect the learning and memory ability of mice. Hematoxylin-eosin(HE) staining was applied to observe the morphology of neuronal cells in the cortical area of mice. Immunofluorescence was used to detect the protein expressions of ß-amyloid(Aß_(1-42)), CD86, and arginase 1(Arg1). The mRNA levels of interleukin(IL)-1ß, IL-6, and IL-10 in the cortex of mice were detected by real-time fluorescence quantitative polymerase chain reaction(RT-qPCR). The protein expressions of TREM2, phosphoinositide-3 kinase(PI3K), Akt, GSK3ß, and beta-catenin(ß-catenin) in mouse cortex were determined by Western blot. The results indicated that the escape latency of the model group was significantly prolonged, and the residence time in the target quadrant and the number of crossing the platform were significantly reduced compared with the normal group. Mice in the model group had a significantly lower number of neurons in the cortex and showed nuclear pyknosis and a significant increase in the expressions of Aß_(1-42) and CD86. The mRNA levels of IL-1ß and IL-6 in tissue were significantly increased, IL-10 were increased, while Arg1 were significantly decreased. The expression of TREM2, p-PI3K(Y607), p-Akt(T308), p-GSK3ß(Ser9), and ß-catenin in the cortex were significantly down-regulated. Compared with the model group, the escape latency of the mice in the administration group was significantly shortened, and the number of crossing the platform and the residence time in the target quadrant were significantly increased. Furthermore, the number of neurons in the cortex of mice was increased, and nuclear pyknosis was improved. Aß_(1-42) deposition was decreased significantly. The mRNA levels of IL-1ß, IL-6 and CD86 were significantly decreased, while IL-10 and Arg1 levels were significantly increased. The expression of TREM2, p-PI3K(Y607), p-Akt(T308), p-GSK3ß(Ser9), and ß-catenin protein in the cortex of each administration group was significantly up-regulated compared with the model group. In conclusion, Huanglian Jiedu Decoction reduced the expression of Aß_(1-42) and neuroinflammation to a neuro-protective effect, thereby improving the learning and memory ability in APP/PS1 mice, which may be related to the TREM2/Akt/GSK3ß signaling pathway.


Assuntos
Doença de Alzheimer , Córtex Cerebral , Medicamentos de Ervas Chinesas , Glicogênio Sintase Quinase 3 beta , Glicoproteínas de Membrana , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-akt , Receptores Imunológicos , Animais , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/administração & dosagem , Camundongos , Córtex Cerebral/metabolismo , Córtex Cerebral/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Masculino , Transdução de Sinais/efeitos dos fármacos , Humanos
9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(3): 535-543, 2024 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-38932540

RESUMO

Magnetic resonance imaging (MRI) plays a crucial role in the diagnosis of ischemic stroke. Accurate segmentation of the infarct is of great significance for selecting intervention treatment methods and evaluating the prognosis of patients. To address the issue of poor segmentation accuracy of existing methods for multiscale stroke lesions, a novel encoder-decoder architecture network based on depthwise separable convolution is proposed. Firstly, this network replaces the convolutional layer modules of the U-Net with redesigned depthwise separable convolution modules. Secondly, an modified Atrous spatial pyramid pooling (MASPP) is introduced to enlarge the receptive field and enhance the extraction of multiscale features. Thirdly, an attention gate (AG) structure is incorporated at the skip connections of the network to further enhance the segmentation accuracy of multiscale targets. Finally, Experimental evaluations are conducted using the ischemic stroke lesion segmentation 2022 challenge (ISLES2022) dataset. The proposed algorithm in this paper achieves Dice similarity coefficient (DSC), Hausdorff distance (HD), sensitivity (SEN), and precision (PRE) scores of 0.816 5, 3.668 1, 0.889 2, and 0.894 6, respectively, outperforming other mainstream segmentation algorithms. The experimental results demonstrate that the method in this paper effectively improves the segmentation of infarct lesions, and is expected to provide a reliable support for clinical diagnosis and treatment.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , AVC Isquêmico , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , AVC Isquêmico/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imagem Multimodal/métodos , Redes Neurais de Computação
10.
Angew Chem Int Ed Engl ; 63(34): e202405584, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-38797714

RESUMO

Large dissymmetry factor of the circularly polarized luminescence (gCPL) was observed in ligand and coordination tuned chiral tetrakis europium (Eu(III)) complexes with ammonium cations. The gCPL value was estimated to be -1.54, which is the largest among chiral luminescent molecules. Through photophysical measurements, single crystal X-ray structural analyses and quantum chemical calculations, changes in the geometric and electronic structures were observed for a series of chiral tetrakis Eu(III) complexes which enhanced the gCPL value. The emission quantum yield and photosensitized energy transfer efficiencies of chiral Eu(III) complexes with ammonium cations were also larger than those of chiral Eu(III) complex with Cs+. Based on the systematic modifications and analyses for chiral tetrakis Eu(III) complex, effect of the ammonium cation on enhanced CPL brightness is reported.

11.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(2): 201-206, 2024 Feb 15.
Artigo em Zh | MEDLINE | ID: mdl-38436320

RESUMO

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder in children and adolescents, and its etiology and pathogenesis are still unclear. Brain is the organ with the largest oxygen consumption in human body and is easily affected by oxidative imbalance. Oxidative stress has become the key research direction for the pathogenesis of ADHD, but there is still a lack of relevant studies in China. Based on the latest research findings in China and overseas, this article reviews the clinical and experimental studies on oxidative stress in ADHD and explores the association of oxidative stress with neurotransmitter imbalance, neuroinflammation, and cell apoptosis in the pathogenesis of ADHD, so as to provide new research ideas for exploring the pathogenesis of ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Adolescente , Criança , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Estresse Oxidativo , Apoptose , Encéfalo , China
12.
J Am Chem Soc ; 145(3): 1542-1547, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36622693

RESUMO

Regioselective difunctionalization of arenes remains a long-standing challenge in organic chemistry. We report a novel and general Fe/Ti synergistic methodology for regioselective synthesis of various polysubstituted arenes through either E/E' or Nu/E ortho difunctionalizations of arenes. Preliminary results showed that an unprecedented 1,2-Fe/Ti heterobimetallic arylene intermediate bearing two distinct C-M bonds is essential to the regioselective difunctionalization.

13.
Rev Cardiovasc Med ; 24(4): 119, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-39076272

RESUMO

Atrial fibrillation (AF) is one of the most common cardiac arrhythmias, but its pathogenesis is still poorly understood. Catheter ablation is one of the most effective treatments for AF, but recurrence after ablation remains a challenge. There has been much research into the association of AF recurrence with several factors, including genetics. Over the past decade or so, significant advances have been made in the genetic architecture of atrial fibrillation. Genome-wide association studies (GWAS) have identified over 100 loci for genetic variants associated with atrial fibrillation. However, there is relatively little information on the systematic assessment of the genes related to AF recurrence after ablation. In this review article, we highlight the value of genetic polymorphisms in atrial fibrillation recurrence after catheter ablation and their potential mechanisms in the recurrence process to enhance our understanding of atrial fibrillation recurrence and contribute to individualized treatment strategies for patients with AF.

14.
Curr Atheroscler Rep ; 25(10): 751-768, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37768409

RESUMO

PURPOSE OF REVIEW: Acute coronary syndrome (ACS) and non-alcoholic fatty liver disease (NAFLD) are two clinically common disease entities that share numerous risk factors. This review aimed to discuss the impacts of NAFLD on ACS. RECENT FINDINGS: In an era of improved control of traditional risk factors, the substantial burden of cardiometabolic abnormalities has caused widespread concern. NAFLD is considered the hepatic component of metabolic syndrome, which can exert an impact on human health beyond the liver. Accumulating studies have demonstrated that NAFLD is closely related to cardiovascular disease, especially coronary artery disease. Interestingly, although recent data have suggested an association between NAFLD and the incidence and outcomes of ACS, the results are not consistent. In this review, we comprehensively summarized evidence and controversies regarding whether NAFLD is a contributor to either the development of ACS or worse outcomes in patients with ACS. The potential pathophysiological and molecular mechanisms involved in the impacts of NAFLD on ACS were also elucidated.


Assuntos
Síndrome Coronariana Aguda , Síndrome Metabólica , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Síndrome Coronariana Aguda/epidemiologia , Fatores de Risco
15.
Inorg Chem ; 62(41): 16794-16800, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37733612

RESUMO

Novel hydrophilic and color-changeable single chameleon luminophores composed of Tb(III)/Sm(III) nona-nuclear clusters [TbxSm9-x(Sal-PEG-n)16(µ-OH)10]+(NO3)- (x = 1, 2, 3, and 9; Sal-PEG-n: salicylate polyethylene glycolmethylester, n = 2 and 4) are reported for water mapping measurements. Their characteristic sandglass structures and aggregates were analyzed using X-ray single crystal analysis and dynamic light scattering (DLS) measurements. The green- and yellow-luminescence of [Tb3Sm6(Sal-PEG-4)16(µ-OH)]+(NO3)- in water were observed at 20 and 50 °C, respectively. The ratio-metric luminescence analysis using green Tb(III) and orange Sm(III) emission bands is a promising candidate for exact temperature distribution measurements in fluid dynamics. The effective temperature-sensing property based on the competitive intramolecular energy transfer processes between Tb(III)-to-ligand and Tb(III)-to-Sm(III) in a non-a-nuclear cluster is explained using temperature-dependent kinetic analyses in the excited state.

16.
Org Biomol Chem ; 21(26): 5451-5456, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37337774

RESUMO

Artemisia annua, also known as "Qinghao" in Chinese, is a famous traditional Chinese medicine and has been used for the treatment of malaria and various tumors. In this study, three novel sesquiterpenoid-flavonol hybrids, artemannuols A-C (1-3), were isolated and elucidated by extensive spectral data and ECD calculations. Structurally, artemannuols A-C (1-3) are the first examples of sesquiterpenoid-flavonol hybrids fused by an ether bond, among which artemannuols A and B (1 and 2) are composed of bisabolane-type sesquiterpenoid and flavonol moieties, and artemannuol C (3) is composed of humulane-type sesquiterpenoid and flavonol moieties. The antihepatoma assay suggested that compounds 1-3 showed inhibitory effects against HepG2, Huh7, and SK-Hep-1 cell lines with IC50 values in the range of 32.7 to 70.4 µM.


Assuntos
Artemisia annua , Sesquiterpenos , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Linhagem Celular
17.
Mikrochim Acta ; 190(9): 358, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37603114

RESUMO

An electrochemical aptsensor for deoxynivalenol determination was successfully designed and constructed based on a defective bimetallic organic framework (denoted as ZrTi-MOF). The high porosity, large specific surface area, several structural defects, mixed metal clusters, and rich functionality of ZrTi-MOF markedly enhanced its electrochemical activity and facilitated the aptamer immobilization. As a result, the ZrTi-MOF-based aptasensor shows high sensitivity to detect deoxynivalenol via specific recognition between aptamer and deoxynivalenol, as well as the formation of aptamer-deoxynivalenol complex. On this basis, the developed ZrTi-MOF-based impedimetric aptasensor showed a low detection limit of 0.24 fg mL-1 for deoxynivalenol determination in the deoxynivalenol concentration range 1 fg mL-1- 1 ng mL-1 under optimized conditions, which also exhibited satisfactory selectivity, stability, reproducibility, and regenerability. Furthermore, determination of deoxynivalenol was achieved in bread and wheat flour samples via the developed ZrTi-MOF-based deoxynivalenol aptasensor. The result from this study showed that the ZrTi-MOF-based electrochemical aptasensor could become a promising strategy for detecting deoxynivalenol in foodstuffs in the future.


Assuntos
Estruturas Metalorgânicas , Titânio , Farinha , Reprodutibilidade dos Testes , Triticum , Zircônio , Oligonucleotídeos
18.
Chemistry ; 28(48): e202200716, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-35754004

RESUMO

A complex comprising one [Re(CO)3 ]+ unit and a phthalocyanine (Pc) ligand (Re1 Pc) is shown to function as a photo-induced CO-releasing molecule (photoCORM) in the presence of O2 and a coordinative solvent under irradiation with red light, which can deeply penetrate living tissues. Transient absorption spectroscopic measurements indicate very short excited-state lifetimes and ultrafast intersystem crossing for Re1 Pc and Re2 Pc, which contains two [Re(CO)3 ]+ units. The excited-state properties are ascribed to efficient spin-orbit coupling and large Franck-Condon factors originating from the complexes' distorted structures, that is, unsymmetric coordination of [Re(CO)3 ]+ unit(s), one of which was confirmed by single-crystal X-ray analysis of a symmetrically substituted Pc with two [Re(CO)3 ]+ units. Re1 Pc represents a promising red-light-driven photoCORM that can be applied in biological environments or therapeutic applications.


Assuntos
Rênio , Indóis , Isoindóis , Ligantes , Luz , Rênio/química
19.
Ophthalmic Res ; 65(6): 605-614, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35843209

RESUMO

Immunoglobin G4 (IgG4)-related disease in the eye and ocular adnexa (IgG4-ROD) is a newly discovered autoimmune disease that histologically exhibits extensive lymphocyte and plasma cell infiltration, occlusive phlebitis, and mat or whorled fibrosis. The disease can affect multiple ocular tissues and organs, such as the lacrimal gland, extraocular muscles, orbital fat, and trigeminal nerve. The main clinical manifestations are chronic, painless swelling of the orbit or unilateral orbit and proptosis, which may be accompanied by peripheral lymphadenopathy. Usually, visual impairment is not apparent, but in severe cases, it can cause a loss of function of the tissues and organs involved and affect the daily lives of patients. The pathogenesis of IgG4-ROD is not clear. Based on existing literature, it is speculated that it may be related to factors such as autoantibody production, microbial infection, and genetic inheritance. For the treatment of IgG4-ROD, glucocorticoids, immunosuppressive agents, biological agents, and surgery are mainly used in clinical practice. Although these treatment methods can achieve a particular effect, they have limitations, such as high recurrence rates, serious side effects, and postoperative complications. With the increase in IgG4-ROD-related reports, some progress has been made in the current understanding and research of the disease.


Assuntos
Oftalmopatias , Doença Relacionada a Imunoglobulina G4 , Humanos , Doença Relacionada a Imunoglobulina G4/diagnóstico
20.
Entropy (Basel) ; 24(12)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36554192

RESUMO

Aggregate measurement and analysis are critical for civil engineering. Multiple entropy thresholding (MET) is inefficient, and the accuracy of related optimization strategies is unsatisfactory, which results in the segmented aggregate images lacking many surface roughness and aggregate edge features. Thus, this research proposes an autonomous segmentation model (i.e., PERSSA-MET) that optimizes MET based on the chaotic combination strategy sparrow search algorithm (SSA). First, aiming at the characteristics of the many extreme values of an aggregate image, a novel expansion parameter and range-control elite mutation strategies were studied and combined with piecewise mapping, named PERSSA, to improve the SSA's accuracy. This was compared with seven optimization algorithms using benchmark function experiments and a Wilcoxon rank-sum test, and the PERSSA's superiority was proved with the tests. Then, PERSSA was utilized to swiftly determine MET thresholds, and the METs were the Renyi entropy, symmetric cross entropy, and Kapur entropy. In the segmentation experiments of the aggregate images, it was proven that PERSSA-MET effectively segmented more details. Compared with SSA-MET, it achieved 28.90%, 12.55%, and 6.00% improvements in the peak signal-to-noise ratio (PSNR), the structural similarity (SSIM), and the feature similarity (FSIM). Finally, a new parameter, overall merit weight proportion (OMWP), is suggested to calculate this segmentation method's superiority over all other algorithms. The results show that PERSSA-Renyi entropy outperforms well, and it can effectively keep the aggregate surface texture features and attain a balance between accuracy and speed.

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