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1.
Cell ; 185(22): 4082-4098.e22, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36198318

RESUMO

The mechanism that initiates autophagosome formation on the ER in multicellular organisms is elusive. Here, we showed that autophagy stimuli trigger Ca2+ transients on the outer surface of the ER membrane, whose amplitude, frequency, and duration are controlled by the metazoan-specific ER transmembrane autophagy protein EPG-4/EI24. Persistent Ca2+ transients/oscillations on the cytosolic ER surface in EI24-depleted cells cause accumulation of FIP200 autophagosome initiation complexes on the ER. This defect is suppressed by attenuating ER Ca2+ transients. Multi-modal SIM analysis revealed that Ca2+ transients on the ER trigger the formation of dynamic and fusion-prone liquid-like FIP200 puncta. Starvation-induced Ca2+ transients on lysosomes also induce FIP200 puncta that further move to the ER. Multiple FIP200 puncta on the ER, whose association depends on the ER proteins VAPA/B and ATL2/3, assemble into autophagosome formation sites. Thus, Ca2+ transients are crucial for triggering phase separation of FIP200 to specify autophagosome initiation sites in metazoans.


Assuntos
Autofagossomos , Cálcio , Animais , Autofagossomos/metabolismo , Cálcio/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas Relacionadas à Autofagia/metabolismo , Autofagia , Proteínas de Ciclo Celular/metabolismo
2.
Mol Cell ; 81(13): 2823-2837.e9, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34015248

RESUMO

DNA-induced liquid-liquid phase separation of cyclic GMP-AMP synthase (cGAS) triggers a potent response to detect pathogen infection and promote innate immune signaling. Whether and how pathogens manipulate cGAS-DNA condensation to mediate immune evasion is unknown. We report the identification of a structurally related viral tegument protein family, represented by ORF52 and VP22 from gamma- and alpha-herpesvirinae, respectively, that employs a conserved mechanism to restrict cGAS-DNA phase separation. ORF52/VP22 proteins accumulate into, and effectively disrupt, the pre-formed cGAS-DNA condensation both in vitro and in cells. The inhibition process is dependent on DNA-induced liquid-liquid phase separation of the viral protein rather than a direct interaction with cGAS. Moreover, highly abundant ORF52 proteins carried within viral particles are able to target cGAS-DNA phase separation in early infection stage. Our results define ORF52/VP22-type tegument proteins as a family of inhibitors targeting cGAS-DNA phase separation and demonstrate a mechanism for how viruses overcome innate immunity.


Assuntos
Alphaherpesvirinae , Betaherpesvirinae , DNA , Infecções por Herpesviridae , Evasão da Resposta Imune , Nucleotidiltransferases , Proteínas Estruturais Virais , Alphaherpesvirinae/química , Alphaherpesvirinae/genética , Alphaherpesvirinae/imunologia , Betaherpesvirinae/química , Betaherpesvirinae/genética , Betaherpesvirinae/imunologia , DNA/química , DNA/genética , DNA/imunologia , Células HEK293 , Células HeLa , Infecções por Herpesviridae/genética , Infecções por Herpesviridae/imunologia , Humanos , Imunidade Inata , Nucleotidiltransferases/química , Nucleotidiltransferases/genética , Nucleotidiltransferases/imunologia , Proteínas Estruturais Virais/química , Proteínas Estruturais Virais/genética , Proteínas Estruturais Virais/imunologia
3.
Plant Physiol ; 196(1): 95-111, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38630866

RESUMO

Ginkgo (Ginkgo biloba L.) is one of the earliest extant species in seed plant phylogeny. Embryo development patterns can provide fundamental evidence for the origin, evolution, and adaptation of seeds. However, the architectural and morphological dynamics during embryogenesis in G. biloba remain elusive. Herein, we obtained over 2,200 visual slices from 3 stages of embryo development using micro-computed tomography imaging with improved staining methods. Based on 3-dimensional (3D) spatiotemporal pattern analysis, we found that a shoot apical meristem with 7 highly differentiated leaf primordia, including apical and axillary leaf buds, is present in mature Ginkgo embryos. 3D rendering from the front, top, and side views showed 2 separate transport systems of tracheids located in the hypocotyl and cotyledon, representing a unique pattern of embryogenesis. Furthermore, the morphological dynamic analysis of secretory cavities indicated their strong association with cotyledons during development. In addition, we identified genes GbLBD25a (lateral organ boundaries domain 25a), GbCESA2a (cellulose synthase 2a), GbMYB74c (myeloblastosis 74c), GbPIN2 (PIN-FORMED 2) associated with vascular development regulation, and GbWRKY1 (WRKYGOK 1), GbbHLH12a (basic helix-loop-helix 12a), and GbJAZ4 (jasmonate zim-domain 4) potentially involved in the formation of secretory cavities. Moreover, we found that flavonoid accumulation in mature embryos could enhance postgerminative growth and seedling establishment in harsh environments. Our 3D spatial reconstruction technique combined with multiomics analysis opens avenues for investigating developmental architecture and molecular mechanisms during embryogenesis and lays the foundation for evolutionary studies of embryo development and maturation.


Assuntos
Ginkgo biloba , Sementes , Ginkgo biloba/genética , Ginkgo biloba/embriologia , Sementes/genética , Sementes/crescimento & desenvolvimento , Imageamento Tridimensional/métodos , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Microtomografia por Raio-X , Cotilédone/genética , Multiômica
4.
Nano Lett ; 24(25): 7792-7799, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38860501

RESUMO

Disease biomarkers in tears are crucial for clinical diagnosis and health monitoring. However, the limited volume of tear samples, low concentration of tear biomarkers, and complex tear composition present challenges for precise testing. We introduce a spot-on testing platform of metal-organic framework (MOF)-based surface-enhanced Raman scattering (SERS) capillary column, which is capable of target molecules selective separation and enrichment for tear biomarkers in situ detection. It consists of Au nanostars for effective SERS signal and a porous MOF shell for separating impurities through molecular sieving effect. This platform allows for simultaneous collection and detection of tear, capturing the disease biomarker malondialdehyde in tears with a 9.38 × 10-9 mol/L limit of detection. Moreover, we designed a hand-held device based on this tubular SERS sensor, successfully diagnosing patients with dry eye disease. This functional capillary column enables noninvasive and rapid diagnosis of biomarkers in biofluids, providing potential for disease diagnosis and healthcare monitoring.


Assuntos
Biomarcadores , Ouro , Malondialdeído , Estruturas Metalorgânicas , Análise Espectral Raman , Lágrimas , Análise Espectral Raman/métodos , Lágrimas/química , Estruturas Metalorgânicas/química , Humanos , Malondialdeído/análise , Ouro/química , Biomarcadores/análise , Síndromes do Olho Seco/diagnóstico , Limite de Detecção , Nanopartículas Metálicas/química
5.
BMC Genomics ; 25(1): 921, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39363266

RESUMO

BACKGROUND: Myocardial infarction (MI) induces complex transcriptional changes across diverse cardiac cell types. Single-cell RNA sequencing (scRNA-seq) provides an unparalleled ability to discern cellular diversity during infarction, yet the veracity of these discoveries necessitates confirmation. This investigation sought to elucidate MI mechanisms by integrating scRNA-seq and bulk RNA-seq data. METHODS: Publicly available scRNA-seq (GSE136088) and bulk RNA-seq (GSE153485) data from mice MI models were analyzed. Cell types were annotated, and differential expression analysis conducted. Bulk RNA-seq underwent quality control, principal component analysis, and differential expression analysis. RESULTS: In scRNA-seq data, the comparison between MI and sham groups unveiled a reduction in endothelial cell populations, but macrophages and monocytes increased. Within fibroblast subgroups, three distinct categories were discerned, with two exhibiting upregulation in MI. Notably, endothelial cells exhibited an elevated expression of genes associated with apoptosis and ferroptosis. In bulk RNA-seq analysis, distinct patterns emerged when comparing MI and sham groups. Specifically, six genes linked to endothelial ferroptosis exhibited heightened expression in MI group, thereby corroborating the scRNA-seq findings. Moreover, the examination of isolated cardiac macrophages from mice MI model revealed increased expression of Spp1, Col1a2, Col3a1, Ctsd, and Lgals3 compared to sham group, thus substantiating the dysregulation of macrophage apoptosis-related proteins following MI. CONCLUSION: MI altered the transcriptomic landscapes of cardiac cells with increased expression of apoptotic genes. Moreover, the upregulation of macrophage apoptosis marker was confirmed within MI models. The presence of endothelial cell depletion and ferroptosis in MI has been demonstrated.


Assuntos
Infarto do Miocárdio , RNA-Seq , Análise de Célula Única , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Animais , Camundongos , Perfilação da Expressão Gênica , Análise de Sequência de RNA , Macrófagos/metabolismo , Células Endoteliais/metabolismo , Transcriptoma , Análise da Expressão Gênica de Célula Única
6.
Small ; 20(35): e2400855, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38563589

RESUMO

The transition metal oxides/sulfides are considered promising catalysts due to their abundant resources, facile synthesis, and reasonable electrocatalytic activity. Herein, a significantly improved intrinsic catalytic activity is achieved for constructing a Co-based nanocrystal (Co-S@NC) with the coordination of Co─S, Co─S─C, and Co─Nx─C. The calculational and experimental results demonstrate that the diversified chemical environment of Co-cations induces the transition of 3d orbitals to a high spin-state that exhibits the coexistence of Co2+ with fully occupied dπ orbitals and Co3+ with unpaired electrons in dπ orbitals. The diverse dπ orbitals occupation contributes to an elevated d-band center of Co ions, which accelerates oxygen reduction reaction and oxygen evolution reaction electrocatalytic kinetics of the Co-S@NC nanocrystal. Therefore, the Li-O2 batteries with Co-S@NC as cathode catalyst exhibit 300 cycles at the current density of 500 mA g-1 with a cut-off capacity of 1000 mAh g-1. Moreover, the ultrahigh discharge specific capacity of 34 587 mAh g-1 is obtained at a current density of 1000 mA g-1, corresponding to the energy density 949 Wh kg-1 of a prototype Li-O2 battery. The study on 3d orbital regulation of nanocrystals provides an innovative strategy for bifunctional electrocatalysts toward the practical application of metal-air batteries.

7.
Plant Cell ; 33(4): 1196-1211, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-33604650

RESUMO

Arabidopsis thaliana CONSTANS (CO) is an essential transcription factor that promotes flowering by activating the expression of the floral integrator FLOWERING LOCUS T (FT). A number of histone modification enzymes involved in the regulation of flowering have been identified, but the involvement of epigenetic mechanisms in the regulation of the core flowering regulator CO remains unclear. Previous studies have indicated that the transcription factors, FLOWERING BHLH1 (FBH1), FBH2, FBH3, and FBH4, function redundantly to activate the expression of CO. In this study, we found that the KDM3 group H3K9 demethylase JMJ28 interacts with the FBH transcription factors to activate CO by removing the repressive mark H3K9me2. The occupancy of JMJ28 on the CO locus is decreased in the fbh quadruple mutant, suggesting that the binding of JMJ28 is dependent on FBHs. Furthermore, genome-wide occupancy profile analyses indicate that the binding of JMJ28 to the genome overlaps with that of FBH3, indicating a functional association of JMJ28 and FBH3. Together, these results indicate that Arabidopsis JMJ28 functions as a CO activator by interacting with the FBH transcription factors to remove H3K9me2 from the CO locus.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Ligação a DNA/metabolismo , Flores/fisiologia , Histona Desmetilases/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Ligação a DNA/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Histona Desmetilases/genética , Histonas/metabolismo , Lisina/metabolismo , Plantas Geneticamente Modificadas/genética , Fatores de Transcrição/genética
8.
Exp Eye Res ; 240: 109795, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38253308

RESUMO

Understanding the molecular complexity of this phenomenon provides innovative targets for maintaining phenotypic integrity during in vitro expansion, thereby advancing corneal endothelial tissue engineering. In this study, we established an in vitro model to simulate endothelial-to-mesenchymal transition (EndMT) in corneal endothelial cells. Through RNA sequencing, we identified 452 upregulated and 163 downregulated genes, resulting in a total of 615 differentially expressed genes. Key pathways enriched by GO and KEGG analysis include extracellular matrix (ECM) regulation and the PI3K-Akt signaling pathway. Potential hub proteins such as THBS1, ITGA5, COL1A1, and SNAI1/2 were also identified, and their dynamic changes at different time points (0, 2, 12, 24 h) were monitored. Uncovering these key pathways and genes may deepen our understanding of the mechanisms underlying EndMT in corneal endothelial cells, providing valuable insights for optimizing in vitro cultivation strategies.


Assuntos
Células Endoteliais , Fosfatidilinositol 3-Quinases , Células Endoteliais/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Sequência de Bases , Transição Epitelial-Mesenquimal/genética , Fator de Crescimento Transformador beta1/metabolismo
9.
Horm Metab Res ; 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37956980

RESUMO

The aim of this study is to report the risk factors of severe statin induced liver injury (SILI). From the database of Shandong ADR Monitoring Center and Outpatients and inpatients in our hospital, SILI cases reported from 2013 to 2021 were extracted and screened. The diagnostic criteria of SILI, the inclusion and exclusion criteria of severe and general SILI were established separately. After the SILI cases were selected and confirmed, the socio-demographic and clinical characteristics were collected. Single factor chi-square test and multi-factor unconditional logistic regression analysis were used to analyze the influencing factors of severe SILI. From 1391 reported cases, 1211 met SILI diagnostic criteria, of which 157 were severe SILI and 964 were general SILI. Univariate analysis showed that age, drug combination, statin category were the influencing factors of severe SILI (p<0.1). Multivariate logistic analysis showed that drug combination and statin category were the influencing factors of severe SILI (p<0.05). Atorvastatin caused the most serious SILI, and its risk is 1.77 times higher than rosuvastatin. The serious SILI risk of drug combination was 2.08 times higher than statin alone. The patient with these factors should be monitored intensively during clinical treatment, to ensure their medication safety.

10.
Helicobacter ; 29(1): e13032, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38009269

RESUMO

BACKGROUND: Some gastrointestinal disorders may be associated with Helicobacter pylori infection, which not only affect maternal health, but may also lead to adverse pregnancy outcomes. We aim to explore the association between H. pylori and gastrointestinal disorders in pregnant women. MATERIALS AND METHODS: In total, 503 patients were retrospectively analyzed and divided into the H. pylori-uninfected group, the H. pylori-infected group, or the H. pylori-eradicated group. We analyzed the influence of H. pylori on gastrointestinal diseases during pregnancy among the groups, as well as the severity, symptoms, laboratory tests of the H. pylori-related diseases. RESULTS: Pregnant women with H. pylori infection had higher risk of nausea and vomiting of pregnancy (NVP) (p < 0.001), severe NVP(p = 0.012), hyperemesis gravidarum (p = 0.027), hematemesis (p = 0.018), hyponatremia (p = 0.033), as well as functional dyspepsia symptoms including epigastric pain (p = 0.004), bloating (p = 0.024), and feeling full quickly in a meal (p = 0.031) compared with those without H. pylori infection. While the prevalence of NVP (p = 0.024), severe NVP (p = 0.009), epigastric pain (p = 0.037), and bloating (p = 0.032) were lower in H. pylori-eradicated pregnant women than in H. pylori-infected women. In addition, pregnant women with H. pylori infection had higher risk of spontaneous preterm birth than whom without H. pylori infection (p = 0.033). CONCLUSIONS: Helicobacter pylori infection was associated with higher risks of NVP, severe NVP, hyperemesis gravidarum, functional dyspepsia, and spontaneous preterm birth in pregnant women.


Assuntos
Dispepsia , Gastrite , Infecções por Helicobacter , Helicobacter pylori , Hiperêmese Gravídica , Complicações Infecciosas na Gravidez , Nascimento Prematuro , Gravidez , Feminino , Recém-Nascido , Humanos , Infecções por Helicobacter/complicações , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/diagnóstico , Complicações Infecciosas na Gravidez/epidemiologia , Hiperêmese Gravídica/complicações , Hiperêmese Gravídica/epidemiologia , Estudos Retrospectivos , Dispepsia/epidemiologia , Dispepsia/complicações , Gastrite/complicações , Dor/complicações
11.
J Immunol ; 208(2): 429-443, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34903642

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces T cell, B cell, and Ab responses that are detected for several months in recovered individuals. Whether this response resembles a typical respiratory viral infection is a matter of debate. In this study, we followed T cell and Ab responses in 24 mainly nonhospitalized human subjects who had recovered from PCR-confirmed SARS-CoV-2 infection at two time points (median of 45 and 145 d after symptom onset). Ab responses were detected in 95% of subjects, with a strong correlation between plasma and salivary anti-spike (anti-S) and anti-receptor binding domain IgG, as well as a correlation between circulating T follicular helper cells and the SARS-CoV-2-specific IgG response. T cell responses to SARS-CoV-2 peptides were determined using intracellular cytokine staining, activation markers, proliferation, and cytokine secretion. All study subjects had a T cell response to at least one SARS-CoV-2 Ag based on at least one T cell assay. CD4+ responses were largely of the Th1 phenotype, but with a lower ratio of IFN-γ- to IL-2-producing cells and a lower frequency of CD8+:CD4+ T cells than in influenza A virus (IAV)-specific memory responses within the same subjects. Analysis of secreted molecules also revealed a lower ratio of IFN-γ to IL-2 and an altered cytotoxic profile for SARS-CoV-2 S- and nucleocapsid-specific responses compared with IAV-specific responses. These data suggest that the memory T cell phenotype after a single infection with SARS-CoV-2 persists over time, with an altered cytokine and cytotoxicity profile compared with long-term memory to whole IAV within the same subjects.


Assuntos
Formação de Anticorpos , COVID-19/imunologia , Imunidade Celular , Imunoglobulina G/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Células Th1/imunologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
12.
Neuroradiology ; 66(9): 1537-1551, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38676749

RESUMO

PURPOSE: The Centiloid project helps calibrate the quantitative amyloid-ß (Aß) load into a unified Centiloid (CL) scale that allows data comparison across multi-site. How the smaller regional amyloid converted into CL has not been attempted. We first aimed to express regional Aß deposition in CL using [18F]Flutemetamol and evaluate regional Aß deposition in CL with that in standardized uptake value ratio (SUVr). Second, we aimed to determine the presence or absence of focal Aß deposition by measuring regional CL in equivocal cases showing negative global CL. METHODS: Following the Centiloid project pipeline, Level-1 replication, Level-2 calibration, and quality control were completed to generate corresponding Centiloid conversion equations to convert SUVr into Centiloid at regional levels. In equivocal cases, the regional CL was compared with visual inspection to evaluate regional Aß positivity. RESULTS: 14 out of 16 regional conversions from [18F]Flutemetamol SUVr to Centiloid successfully passed the quality control, showing good reliability and relative variance, especially precuneus/posterior cingulate and prefrontal regions with good stability for Centiloid scaling. The absence of focal Aß deposition could be detected by measuring regional CL, showing a high agreement rate with visual inspection. The regional Aß positivity in the bilateral anterior cingulate cortex was most prevalent in equivocal cases. CONCLUSION: The expression of regional brain Aß deposition in CL with [18F]Flutemetamol has been attempted in this study. Equivocal cases had focal Aß deposition that can be detected by measuring regional CL.


Assuntos
Peptídeos beta-Amiloides , Compostos de Anilina , Benzotiazóis , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Humanos , Peptídeos beta-Amiloides/metabolismo , Feminino , Masculino , Idoso , Tomografia por Emissão de Pósitrons/métodos , Reprodutibilidade dos Testes , Doença de Alzheimer/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Pessoa de Meia-Idade , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Calibragem
13.
Appl Microbiol Biotechnol ; 108(1): 304, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38643456

RESUMO

Tobramycin is an essential and extensively used broad-spectrum aminoglycoside antibiotic obtained through alkaline hydrolysis of carbamoyltobramycin, one of the fermentation products of Streptoalloteichus tenebrarius. To simplify the composition of fermentation products from industrial strain, the main byproduct apramycin was blocked by gene disruption and constructed a mutant mainly producing carbamoyltobramycin. The generation of antibiotics is significantly affected by the secondary metabolism of actinomycetes which could be controlled by modifying the pathway-specific regulatory proteins within the cluster. Within the tobramycin biosynthesis cluster, a transcriptional regulatory factor TobR belonging to the Lrp/AsnC family was identified. Based on the sequence and structural characteristics, tobR might encode a pathway-specific transcriptional regulatory factor during biosynthesis. Knockout and overexpression strains of tobR were constructed to investigate its role in carbamoyltobramycin production. Results showed that knockout of TobR increased carbamoyltobramycin biosynthesis by 22.35%, whereas its overexpression decreased carbamoyltobramycin production by 10.23%. In vitro electrophoretic mobility shift assay (EMSA) experiments confirmed that TobR interacts with DNA at the adjacent tobO promoter position. Strains overexpressing tobO with ermEp* promoter exhibited 36.36% increase, and tobO with kasOp* promoter exhibited 22.84% increase in carbamoyltobramycin titer. When the overexpressing of tobO and the knockout of tobR were combined, the production of carbamoyltobramycin was further enhanced. In the shake-flask fermentation, the titer reached 3.76 g/L, which was 42.42% higher than that of starting strain. Understanding the role of Lrp/AsnC family transcription regulators would be useful for other antibiotic biosynthesis in other actinomycetes. KEY POINTS: • The transcriptional regulator TobR belonging to the Lrp/AsnC family was identified.  • An oxygenase TobO was identified within the tobramycin biosynthesis cluster. • TobO and TobR have significant effects on the synthesis of carbamoyltobramycin.


Assuntos
Actinobacteria , Actinomycetales , Engenharia Metabólica , Antibacterianos , Tobramicina
14.
J Chem Phys ; 161(13)2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39351942

RESUMO

Lithium-sulfur batteries hold great promise as energy storage systems, but the shuttle effect of lithium polysulfides (LiPS) and large volume variation limit their capacity and cycle life. We have developed CoFe alloy wrapped in N-doped porous carbon spheres (e-CF@NC) with a core-shell structure through simple copolymerization and pyrolysis. The nitrogen-doped porous carbon shell provides electron and ion transport channels and more active sites for electrolyte ion adsorption. The high chemically stable carbon can limit the segregation of polysulfides, further improving the battery cycling stability. Besides, the inside CoFe alloy particles catalyze the conversion between LiPS and Li2S, speeding up reaction kinetics and reducing solvation of active sites. Consequently, lithium-sulfur batteries with e-CF@NC-2 as the cathode display a high initial specific capacity of 1146 mA h g-1 at 0.1 C, excellent rate performance (891 mA h g-1 at 1 C, 741 mA h g-1 at 2 C), and satisfied cycle stability (average capacity decay rate of 0.033% per cycle at 1 C for 300 cycles), demonstrating significant application potential.

15.
Acta Radiol ; 65(5): 422-431, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38584372

RESUMO

BACKGROUND: Gallbladder cancer is a rare but aggressive malignancy that is often diagnosed at an advanced stage and is associated with poor outcomes. PURPOSE: To develop a radiomics model to discriminate between benign and malignant gallbladder lesions using enhanced computed tomography (CT) imaging. MATERIAL AND METHODS: All patients had a preoperative contrast-enhanced CT scan, which was independently analyzed by two radiologists. Regions of interest were manually delineated on portal venous phase images, and radiomics features were extracted. Feature selection was performed using mRMR and LASSO methods. The patients were randomly divided into training and test groups at a ratio of 7:3. Clinical and radiomics parameters were identified in the training group, three models were constructed, and the models' prediction accuracy and ability were evaluated using AUC and calibration curves. RESULTS: In the training group, the AUCs of the clinical model and radiomics model were 0.914 and 0.968, and that of the nomogram model was 0.980, respectively. There were statistically significant differences in diagnostic accuracy between nomograms and radiomics features (P <0.05). There was no significant difference in diagnostic accuracy between the nomograms and clinical features (P >0.05) or between the clinical features and radiomics features (P >0.05). In the testing group, the AUC of the clinical model and radiomics model were 0.904 and 0.941, and that of the nomogram model was 0.948, respectively. There was no significant difference in diagnostic accuracy between the three groups (P >0.05). CONCLUSION: It was suggested that radiomics analysis using enhanced CT imaging can effectively discriminate between benign and malignant gallbladder lesions.


Assuntos
Meios de Contraste , Neoplasias da Vesícula Biliar , Vesícula Biliar , Tomografia Computadorizada por Raios X , Humanos , Masculino , Feminino , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Pessoa de Meia-Idade , Idoso , Diagnóstico Diferencial , Adulto , Vesícula Biliar/diagnóstico por imagem , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Nomogramas , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Radiômica
16.
Acta Radiol ; 65(8): 913-921, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38839094

RESUMO

BACKGROUND: The diagnostic impact of deep learning computed tomography (CT) reconstruction on intracranial aneurysm (IA) remains unclear. PURPOSE: To quantify the image quality and diagnostic confidence on IA in craniocervical CT angiography (CTA) reconstructed with DEep Learning Trained Algorithm (DELTA) compared to the routine hybrid iterative reconstruction (HIR). MATERIAL AND METHODS: A total of 60 patients who underwent craniocervical CTA and were diagnosed with IA were retrospectively enrolled. Images were reconstructed with DELTA and HIR, where the image quality was first compared in noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). Next, two radiologists independently graded the noise appearance, arterial sharpness, small vessel visibility, conspicuity of calcifications that may present in arteries, and overall image quality, each with a 5-point Likert scale. The diagnostic confidence on IAs of various sizes was also graded. RESULTS: Significantly lower noise and higher SNR and CNR were found on DELTA than on HIR images (all P < 0.05). All five subjective metrics were scored higher by both readers on the DELTA images (all P < 0.05), with good to excellent inter-observer agreement (κ = 0.77-0.93). DELTA images were rated with higher diagnostic confidence on IAs compared to HIR (P < 0.001), particularly for those with size ≤3 mm, which were scored 4.5 ± 0.6 versus 3.4 ± 0.8 and 4.4 ± 0.7 versus 3.5 ± 0.8 by two readers, respectively. CONCLUSION: The DELTA shows potential for improving the image quality and the associated confidence in diagnosing IA that may be worth consideration for routine craniocervical CTA applications.


Assuntos
Angiografia por Tomografia Computadorizada , Aprendizado Profundo , Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Masculino , Angiografia por Tomografia Computadorizada/métodos , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Adulto , Razão Sinal-Ruído , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Angiografia Cerebral/métodos
17.
BMC Musculoskelet Disord ; 25(1): 478, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890605

RESUMO

BACKGROUND: The aim of the study was to investigate the muscle differences in children with osteogenesis imperfecta (OI) using opportunistic low-dose chest CT and to compare different methods for the segmentation of muscle in children. METHODS: This single center retrospective study enrolled children with OI and controls undergoing opportunistic low-dose chest CT obtained during the COVID pandemic. From the CT images, muscle size (cross-sectional area) and density (mean Hounsfield Units [HU]) of the trunk muscles were measured at the mid-T4 and the mid-T10 level using two methods, the fixed thresholds and the Gaussian mixture model. The Bland-Altman method was also used to compute the strength of agreement between two methods. Comparison of muscle results between OI and controls were analyzed with Student t tests. RESULTS: 20 children with OI (mean age, 9.1 ± 3.3 years, 15 males) and 40 age- and sex-matched controls were enrolled. Mean differences between two methods were good. Children with OI had lower T4 and T10 muscle density than controls measured by the fixed thresholds (41.2 HU vs. 48.0 HU, p < 0.01; 37.3 HU vs. 45.9 HU, p < 0.01). However, children with OI had lower T4 muscle size, T4 muscle density, T10 muscle size and T10 muscle density than controls measured by the Gaussian mixture model (110.9 vs. 127.2 cm2, p = 0.03; 44.6 HU vs. 51.3 HU, p < 0.01; 72.6 vs. 88.0 cm2, p = 0.01; 41.6 HU vs. 50.3 HU, p < 0.01, respectively). CONCLUSIONS: Children with OI had lower trunk muscle density indicating that OI might also impair muscle quality. Moreover, the fixed thresholds may not be suitable for segmentation of muscle in children.


Assuntos
Músculo Esquelético , Osteogênese Imperfeita , Tomografia Computadorizada por Raios X , Humanos , Osteogênese Imperfeita/diagnóstico por imagem , Masculino , Feminino , Criança , Estudos Retrospectivos , Estudos de Casos e Controles , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/patologia , Adolescente , COVID-19/diagnóstico por imagem , Doses de Radiação , Pré-Escolar
18.
Molecules ; 29(15)2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39125095

RESUMO

Lead nitrate (LN) is frequently employed as an activator in the flotation of cassiterite using hydroxamic acids as the collectors. This study investigated the effect of LN on the hydrophobic aggregation of cassiterite when benzohydroxamic acid (BHA), hexyl hydroxamate (HHA), and octyl hydroxamate (OHA) were used as the collectors through micro-flotation, focused beam reflectance measurement (FBRM) and a particle video microscope (PVM), zeta potential, and the extended DLVO theory. Micro-flotation tests confirmed that LN activated the flotation of cassiterite using the hydroxamic acids as collectors. Focused beam reflectance measurement (FBRM) and a particle video microscope (PVM) were used to capture in situ data on the changes in size distribution and morphology of cassiterite aggregates during stirring. The FBRM and PVM image results indicated that the addition of LN could promote the formation of hydrophobic aggregates of fine cassiterite, when BHA or HHA was used as the collector, and reduce the dosage of OHA needed to induce the formation of hydrophobic aggregates of cassiterite. The extended DLVO theory interaction energies indicated that the presence of LN could decrease the electrostatic interaction energies (Vedl) and increase the hydrophobic interaction energies (Vhy) between cassiterite particles, resulting in the disappearance of the high energy barriers that existed between the particles in the absence of LN. Thus, cassiterite particles could aggregate in the presence of LN when BHA, HHA, or a low concentration of OHA was used as the collector.

19.
BMC Oral Health ; 24(1): 56, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195412

RESUMO

The effects of Easydo Activator (EA), a new sonic irrigation system, on sealer penetration at the root apex were compared to needle irrigation (NI) and passive ultrasonic irrigation (PUI) in this study. Forty-two single-rooted teeth were prepared and randomly divided into three groups (n = 14): group 1: NI; group 2: PUI; and group 3: EA. A solution of 3% sodium hypochlorite (NaOCl) was used for irrigation. Nine teeth in each group were filled with AH Plus sealer mixed with CY5 fluorescent dye and a single gutta-percha cone. The sealer penetration area, maximum penetration depth and percentage of sealer penetration at 5 mm and 1 mm from the apex were analyzed by confocal laser scanning microscopy (CLSM). The remaining 5 teeth in each group were subjected to test smear layer scores by scanning electron microscopy (SEM). The CLSM evaluation showed that increases in the area, depth and percentage of sealer penetration were detected at 1 and 5 mm from the root apex in the PUI group compared with the NI group, and greater increases were observed in the EA group (P < 0.05). The SEM experiment showed that the lowest scores for the smear layer and debris removal were achieved by the EA group when compared with the PUI and NI groups (P < 0.05). In conclusion, EA was superior to PUI and NI regarding sealer penetration at the root apex during endodontic treatment, and it could provide a new technical idea for clinical root canal therapy.


Assuntos
Camada de Esfregaço , Humanos , Assistência Odontológica , Guta-Percha , Microscopia Confocal , Ultrassom
20.
Mycoscience ; 65(3): 151-155, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39233760

RESUMO

The present study introduces a novel fungus, Cystoderma yongpingense, which was identified in the southwestern region of China. The new species is characterized by a pileus that ranges in color from light orange-red to orange-red; the pileus has a wrinkled surface and is accompanied by a persistent annulus that is membranous and floccose-scaly. Above the annulus, the color transitions from white to yellowish brown. This proposal is substantiated through analyses encompassing both morphological characteristics and phylogenetic relationships. The phylogenetic position of the newly discovered species has been further corroborated through comprehensive maximum likelihood and Bayesian sequence analyses of the ITS + nrLSU DNA regions. Additionally, the technical description of C. yongpingense is enhanced by detailed illustrations and comparative studies with species that are closely related.

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