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1.
Artigo em Inglês | MEDLINE | ID: mdl-39017874

RESUMO

Under the background of the continuous rise of CO2 annual emissions, the development of CO2 capture and utilization technology is urgent. This study focuses on improving the catalytic capacity of the catalyst for CO2 hydrogenation, improving the efficiency of CO2 conversion to methanol, and converting H2 into chemical substances to avoid the danger of H2 storage. Based on the concept of element sharing, the ASMZ (Aluminum Shares Metal Zeolite catalysts) series catalyst was prepared by combining the CuO-ZnO-Al2O3 catalyst with the ZSM-5 zeolite using the amphoteric metal properties of the Al element. The basic structural properties of ASMZ catalysts were compared by XRD, FTIR, and BET characterization. Catalytic properties of samples were measured on a micro fixed-bed reactor. The catalytic mechanism of the catalyst was further analyzed by SEM, TEM, XPS, H2-TPR, and NH3-TPD. The results show that the ASMZ3 catalyst had the highest CO2 conversion rate (26.4%), the highest methanol selectivity (76.0%), and the lowest CO selectivity (15.3%) in this study. This is mainly due to the fact that the preparation method in this study promotes the exposure of effective weakly acidic sites and medium strength acidic sites (facilitating the hydrogenation of CO2 to methanol). At the same time, the close binding of Cu-ZnO-Al2O3 (CZA) and ZSM-5 zeolite also ensures the timely transfer of catalytic products and ensures the timely play of various catalytic active centers. The preparation method of the catalyst in this study also provides ideas for the preparation of other catalysts.

2.
ACS Nano ; 18(28): 18211-18229, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38946122

RESUMO

Transarterial chemoembolization (TACE), the mainstay treatment of unresectable primary liver cancer that primarily employs nondegradable drug-loaded embolic agents to achieve synergistic vascular embolization and locoregional chemotherapy effects, suffers from an inferior drug burst behavior lacking long-term drug release controllability that severely limits the TACE efficacy. Here we developed gelatin-based drug-eluting microembolics grafted with nanosized poly(acrylic acid) serving as a biodegradable ion-exchange platform that leverages a counterion condensation effect to achieve high-efficiency electrostatic drug loading with electropositive drugs such as doxorubicin (i.e., drug loading capacity >34 mg/mL, encapsulation efficiency >98%, and loading time <10 min) and an enzymatic surface-erosion degradation pattern (∼2 months) to offer sustained locoregional pharmacokinetics with long-lasting deep-tumor retention capability for TACE treatment. The microembolics demonstrated facile microcatheter deliverability in a healthy porcine liver embolization model, superior tumor-killing capacity in a rabbit VX2 liver cancer embolization model, and stabilized extravascular drug penetration depth (>3 mm for 3 months) in a rabbit ear embolization model. Importantly, the microembolics finally exhibited vessel remodeling-induced permanent embolization with minimal inflammation responses after complete degradation. Such a biodegradable ion-exchange drug carrier provides an effective and versatile strategy for enhancing long-term therapeutic responses of various local chemotherapy treatments.


Assuntos
Quimioembolização Terapêutica , Doxorrubicina , Animais , Quimioembolização Terapêutica/métodos , Doxorrubicina/química , Doxorrubicina/farmacologia , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Coelhos , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/tratamento farmacológico , Suínos , Resinas Acrílicas/química , Polieletrólitos/química , Portadores de Fármacos/química , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/farmacocinética , Gelatina/química , Nanopartículas/química , Humanos , Liberação Controlada de Fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem
3.
Am J Cancer Res ; 14(3): 996-1014, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590422

RESUMO

RNASEH1-AS1, a long non-coding RNA (lncRNA) divergently transcribed from the antisense strand of its neighboring protein-coding gene ribonuclease H1 (RNASEH1), has recently been demonstrated to be involved in tumor progression. However, the association between RNASEH1-AS1 and hepatocellular carcinoma (HCC) remains unclear. In the present study, first, the expression of RNASEH1-AS1 in HCC and its correlation with clinicopathological features, prognosis, diagnosis, immune cell infiltration of HCC patients was inspected using relevant R packages based on The Cancer Genome Atlas (TCGA) data. RNASEH1-AS1 was found to be up-regulated in most cancer types, including HCC, and its overexpression was significantly associated with histologic grade and AFP level as well as poor prognosis, and was an independent risk factor affecting overall survival with good diagnostic and prognostic values for HCC. RNASEH1-AS1 was inversely associated with the infiltration of most immune cell types, including plasmacytoid dendritic cells (pDC), B cells and neutrophils. Second, a total of 1109 positively co-expressed genes (PCEGs) of RNASEH1-AS1 were screened out in HCC by correlation analysis in batches (|Spearman's r| >0.4 and adjusted P value <0.01). GO and KEGG enrichment analysis indicated that PCEGs of RNASEH1-AS1 were mainly related to RNA processing, ribosome biogenesis, transcription and histone acetylation. The top 10 hub genes (EIF4A3, WDR43, WDR12, DKC1, NAT10, UTP18, DDX18, BYSL, DDX10, PDCD11) were identified by constructing the protein-protein interaction (PPI) network, and they were all highly expressed in HCC and positively correlated with histological grade. Third, a risk model was constructed based on four RNASEH1-AS1-related hub genes (EIF4A3, WDR12, DKC1, and NAT10) with good prognostic predictive potential via univariate Cox and the least absolute selection operator (LASSO) regression analysis. Fourth, experimental validation revealed that RNASEH1-AS1 was significantly elevated in HCC tissues and several cell lines, and its knockdown could suppress the proliferation, migration, and invasion of HCC cells. Finally, mechanistic studies demonstrated that the stability of RNASEH1-AS1 could be regulated by DKC1 via their direct interaction. Taken together, RNASEH1-AS1 may serve as a potential prognostic and diagnostic biomarker and oncogenic lncRNA for HCC.

4.
Sci Total Environ ; 926: 172065, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38556008

RESUMO

As global anthropogenic nitrogen inputs continue to rise, nitrite-dependent anaerobic methane oxidation (N-DAMO) plays an increasingly significant role in CH4 consumption in lake sediments. However, there is a dearth of knowledge regarding the effects of anthropogenic activities on N-DAMO bacteria in lakes in the cold and arid regions. Sediment samples were collected from five sampling areas in Lake Ulansuhai at varying depth ranges (0-20, 20-40, and 40-60 cm). The ecological characterization and niche differentiation of N-DAMO bacteria were investigated using bioinformatics and molecular biology techniques. Quantitative PCR confirmed the presence of N-DAMO bacteria in Lake Ulansuhai sediments, with 16S rRNA gene abundances ranging from 1.72 × 104 to 5.75 × 105 copies·g-1 dry sediment. The highest abundance was observed at the farmland drainage outlet with high available phosphorus (AP). Anthropogenic disturbances led to a significant increase in the abundance of N-DAMO bacteria, though their diversity remained unaffected. The heterogeneous community of N-DAMO bacteria was affected by interactions among various environmental characteristics, with AP and oxidation-reduction potential identified as the key drivers in this study. The Mantel test indicated that the N-DAMO bacterial abundance was more readily influenced by the presence of the denitrification genes (nirS and nirK). Network analysis revealed that the community structure of N-DAMO bacteria generated numerous links (especially positive links) with microbial taxa involved in carbon and nitrogen cycles, such as methanogens and nitrifying bacteria. In summary, N-DAMO bacteria exhibited sensitivity to both environmental and microbial factors under various human disturbances. This study provides valuable insights into the distribution patterns of N-DAMO bacteria and their roles in nitrogen and carbon cycling within lake ecosystems.


Assuntos
Microbiota , Nitritos , Humanos , Lagos/microbiologia , Anaerobiose , Metano , RNA Ribossômico 16S/genética , Bactérias/genética , Methanobacteriaceae , Bactérias Anaeróbias/genética , Oxirredução , Nitrogênio , Carbono , Desnitrificação
5.
Bioresour Technol ; 393: 130029, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37977495

RESUMO

The effects of biodegradable plastics of different thicknesses (30 and 40 µm) and sizes (20 × 20, 2 × 2, and 1 × 1 mm) on anaerobic digestion of food waste and digestate phytotoxicity were investigated. Methane productions (38 days) for the groups with 20 × 20, 2 × 2, and 1 × 1 mm of 30 µm plastics were 92.46, 138.27, and 259.95 mL/gVSremoval, respectively which are nearly 58 % higher than the control group (58.86 mL/gVSremoval). Methane production in 40 µm plastics groups was lower than in 30 µm groups of equal size. All sizes of 30 µm plastics promoted substrate hydrolysis, acidification, and relative abundance of key hydrolytic bacteria and methanogens. Phytotoxicity tests results showed that seed root elongation was inhibited in groups with 40 µm plastics. In conclusion, 30 µm biodegradable plastics were more suitable for anaerobic digestion with food waste than 40 µm.


Assuntos
Plásticos Biodegradáveis , Eliminação de Resíduos , Eliminação de Resíduos/métodos , Esgotos/microbiologia , Perda e Desperdício de Alimentos , Anaerobiose , Alimentos , Estudos de Viabilidade , Plásticos , Metano , Digestão , Reatores Biológicos
6.
Leukemia ; 38(2): 266-280, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38036630

RESUMO

The fate of leukaemia stem cells (LSCs) is determined by both their inherent mechanisms and crosstalk with their niches. Although LSCs were confirmed to be eradicated by restarting senescence, the specific key regulators of LSC resistance to senescence and remodelling of the niche to obtain a microenvironment suitable for stemness remain unknown. Here, we found that RAB27B, a gene regulating exosome secretion, was overexpressed in LSCs and associated with the poor prognosis of acute myeloid leukaemia (AML) patients. The increased RAB27B in LSCs prevented their senescence and maintained their stemness in vitro and in vivo. Mechanically, the increased RAB27B expression in LSCs selectively promoted the loading and release of exosomes rich in senescence-inducing proteins by direct combination. Furthermore, RAB27B-regulated LSC-derived exosomes remodelled the niche and induced senescence of mesenchymal stem cells (MSCs) with increased RAB27B expression ex vivo and in vivo. The increased RAB27B in the senescent MSCs conversely promoted LSC maintenance ex vivo and in vivo via selective excretion of exosomes rich in stemness-promoting proteins. Therefore, we identified the specifically increased RAB27B in LSCs and their educated senescent MSCs as a hub molecule for LSC resistance to senescence and maintenance through crosstalk with its niche via selective exosome excretion.


Assuntos
Exossomos , Leucemia Mieloide Aguda , Células-Tronco Mesenquimais , Humanos , Exossomos/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Neoplásicas/metabolismo , Microambiente Tumoral
7.
Immunobiology ; 229(1): 152781, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38154164

RESUMO

N6-methyladenosine (m6A) is one kind of important epigenetic modification pattern which is extensively involved in immune regulation. The development and progression of autoimmune diseases are closely related to immune dysregulation. Considering that rheumatoid arthritis (RA) is a typical autoimmune disease, the m6A process might be one of the important regulatory mechanisms in the pathogenesis of RA. In this study, we identified five differentially expressed m6A regulators in normal and RA samples from the GEO database. With these five regulators, we constructed the nomogram, and it could accurately identify the risk of RA morbidity. Next, we identified 121 differentially expressed genes (DEGs) between normal and RA samples, of which 36 DEGs were co-expressed with these five m6A regulators. We noted that these DEGs were highly enriched in multiple immunoregulatory signaling pathways, such as cytokine-mediated immune cell chemotaxis, adhesion, and activation. To further characterize the heterogeneity of immunological features, we clustered the RA samples into two subtypes. The C2 subtype has higher infiltration levels of pro-inflammatory cells and activity of pro-inflammatory signaling pathways. Thus, the inflammatory response might be more vigorous in the C2 subtype. Next, we constructed the m6Asig system with the SVM machine learning algorithms and least absolute shrinkage and selection operator (LASSO) regression. The m6Asig could accurately distinguish the C1 and C2 subtypes, which indicated that the m6Asig could be a potential biomarker for the inflammatory activity of RA. Finally, by comparing the information from the CellMiner, TTD, and DrugBank databases, we determined 25 drugs. The targets of these drugs were positively correlated with m6Asig. To be clarified, the above findings were derived from bioinformatics and statistical analyses, and further experimental validation still requires. In summary, this study further revealed the m6A and immunoregulation mechanisms in RA pathogenesis. Also, the m6Asig could be a novel biomarker with potential applicability in the clinical management of RA.


Assuntos
Artrite Reumatoide , Doenças Autoimunes , Humanos , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética , Adenina , Biomarcadores
8.
Foods ; 12(22)2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-38002155

RESUMO

Lipase has great application potential in hydrolyzing residual yolk lipid in egg white liquid to restore its functional properties. In this study, a lipase gene from Bacillus subtilis was expressed in E. coli BL21 (DE3) and named Lip-IM. Results showed that although Lip-IM has stronger specificity for medium- and short-chain substrates than long-chain substrates (C16, C18), due to its excellent enzyme activity, it also has strong hydrolysis activity for long-chain substrates and maintained over 80% activity at 4-20 °C, but significantly reduced when the temperature exceeds 40 °C. The addition of 0.5% Lip-IM enhanced foaming ability by 26% (from 475 to 501%) and reduced liquid precipitation rate by 9% (from 57 to 48%). Furthermore, molecular dynamics (MD) simulations were run to investigate the conformational stability of Lip-IM at different temperatures. Results showed that Lip-IM maintained a stable conformation within the temperature range of 277-303 K. Fluctuations in the flexible area and backbone movement of proteins were identified as the main reasons for its poor thermal stability.

9.
J Agric Food Chem ; 71(41): 15375-15387, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37773011

RESUMO

The Xylo-1 xylosidase, which belongs to the GH43 family, exhibits a high salt tolerance. The present study demonstrated that the catalytic activity of Xylo-1 increased by 195% in the presence of 5 M NaCl. Additionally, the half-life of Xylo-1 increased 25.9-fold in the presence of 1 M NaCl. Through comprehensive analysis including circular dichroism, fluorescence spectroscopy, and molecular dynamics simulations, we elucidated that the presence of Na+ ions increased the contact frequency between the surface acidic amino acids and the surrounding water molecules. This resulted in the stabilization of the surrounding hydration layer of Xylo-1. Additionally, Na+ ions also stabilized the substrate-binding conformation and the fluctuation of water molecules within the active site, which enhanced the catalytic activity of Xylo-1 by increasing the nucleophilic attack by the water molecules. Ultimately, the optimal reaction conditions for the production of xylose by synergistic catalysis with Xylo-1 and xylanase were determined. The results demonstrated that the conversion yield of the method was high for various sources of xylan, indicating the method could have potential industrial applications. This study explored the structure-activity relationship of catalysis in Xylo-1 under high-salt conditions, provides novel insights into the mechanism of halophilic enzymes, and serves as a reference for the industrial application of Xylo-1.


Assuntos
Xilose , Xilosidases , Xilose/metabolismo , Cloreto de Sódio , Xilosidases/química , Xilanos/metabolismo , Água , Íons , Especificidade por Substrato
10.
Cancer Lett ; 575: 216407, 2023 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-37769796

RESUMO

Most patients with acute myeloid leukemia (AML) relapse eventually because of the inability to effectively eliminate leukemia stem cells (LSCs), prompting the search of new therapies to eradicate LSCs. Our previous study demonstrated that miR-34c-5p promotes the clearance of LSCs in an AML mouse model, highlighting its potential as a therapeutic target for eradicating LSCs, but the effective delivery of miR-34c-5p to LSCs remains a great challenge. Here, we employed simultaneous two-step modifications to engineer mesenchymal stem cells (MSCs) and MSC-derived exosomes to create exosomes overexpressing the fused protein lysosome-associated membrane protein 2-interleukin 3 (Lamp2b-IL3) and hematopoietic cell E-selectin/L-selectin ligand (HCELL), and demonstrated that the engineered exosomes exhibited an enhanced ability for bone marrow homing and selective targeting of LSCs. Additionally, using a humanized AML mouse model, we confirmed that the engineered exosomes, loaded with miR-34c-5p, could selectively promote eradication of LSCs and impede the AML development in vivo. In summary, we successfully designed an effective delivery system and provided new insights into the development of novel therapies for delivering miRNA or other molecules to LSCs with greater cellular targeting specificity.


Assuntos
Exossomos , Leucemia Mieloide Aguda , Células-Tronco Mesenquimais , MicroRNAs , Camundongos , Animais , Humanos , Exossomos/genética , Exossomos/metabolismo , Células-Tronco Neoplásicas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Células-Tronco Mesenquimais/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/metabolismo
11.
J Hepatocell Carcinoma ; 10: 1237-1256, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37533602

RESUMO

Purpose: HOX cluster-embedded long noncoding RNAs (HOX-lncRNAs) have been shown to be tightly related to hepatocellular carcinoma (HCC). However, the potential biological roles and underlying molecular mechanism of HOX-lncRNAs in HCC largely remains to be elucidated. Methods: The expression signature of eighteen HOX-lncRNAs in HCC cell lines were measured by qRT-PCR. HOXD-AS2 expression and its clinical significance in HCC was investigated by bioinformatics analysis utilizing the TCGA data. Subcellular localization of HOXD-AS2 in HCC cells was observed by RNA-FISH. Loss­of­function experiments in vitro and in vivo were conducted to probe the roles of HOXD-AS2 in HCC. Potential HOXD-AS2-controlled genes and signaling pathways were revealed by RNA-seq. Rescue experiments were performed to validate that SMYD3 mediates HOXD-AS2 promoting HCC progression. The positive feedback loop of HOXD-AS2 and SMYD3 was identified by luciferase reporter assay and ChIP-qPCR. Results: HOXD-AS2 was dramatically elevated in HCC, and its up-regulation exhibited a positive association with aggressive clinical features (T stage, pathologic stage, histologic grade, AFP level, and vascular invasion) and unfavorable prognosis of HCC patients. HOXD-AS2 was distributed both in the nucleus and the cytoplasm of HCC cells. Knockdown of HOXD-AS2 restrained the proliferation, migration, invasion of HCC cells in vitro, as well as tumor growth in subcutaneous mouse model. Transcriptome analysis demonstrated that SMYD3 expression and activity of MEK/ERK pathway were impaired by silencing HOXD-AS2 in HCC cells. Rescue experiments revealed that SMYD3 as downstream target mediated oncogenic functions of HOXD-AS2 in HCC cells through altering the expression of cyclin B1, cyclin E1, MMP2 as well as the activity of MEK/ERK pathway. Additionally, HOXD-AS2 was uncovered to be positively regulated at transcriptional level by its downstream gene of SMYD3. Conclusion: HOXD-AS2, a novel oncogenic HOX-lncRNA, facilitates HCC progression by forming a positive feedback loop with SMYD3 and activating the MEK/ERK pathway.

12.
Plant Biotechnol J ; 21(11): 2196-2208, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37641539

RESUMO

The CRISPR-Cas systems have been widely used as genome editing tools, with type II and V systems typically introducing small indels, and type I system mediating long-range deletions. However, the precision of type I systems for large fragment deletion is still remained to be optimized. Here, we developed a compact Cascade-Cas3 Dvu I-C system with Cas11c for plant genome editing. The Dvu I-C system was efficient to introduce controllable large fragment deletion up to at least 20 kb using paired crRNAs. The paired-crRNAs design also improved the controllability of deletions for the type I-E system. Dvu I-C system was sensitive to spacer length and mismatch, which was benefit for target specificity. In addition, we showed that the Dvu I-C system was efficient for generating stable transgenic lines in maize and rice with the editing efficiency up to 86.67%. Overall, Dvu I-C system we developed here is powerful for achieving controllable large fragment deletions.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Sistemas CRISPR-Cas/genética , Plantas/genética , Genoma de Planta , Mutação INDEL
13.
J Agric Food Chem ; 71(30): 11692-11703, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37483134

RESUMO

Most GH11 family endo-ß-1,4-xylanases contain a propeptide region linked to the N-terminal region. The mechanistic basis of this region harboring key regulation information for enzyme function, however, remains poorly understood. We reported an investigation on the allosteric regulation mechanism of the propeptide based on biochemical characterization, molecular dynamics simulations, and evolutionary analysis. We discovered that the mutant of truncated propeptide shows a remarkably increased thermal stability (melting temperature increased by 11.5 °C) and catalytic efficiency (1.7-fold kcat/Km value of wild type). Molecular dynamics simulations reveal that long-range fluctuations in the propeptide lead to a conformational perturbation in the catalytic pocket and the thumb region. The probability of sampling the active conformation during the glycosylation step is reduced (i.e., catalytic efficiency). In-depth sequence analysis indicates that the propeptide has a strong plasticity and degeneration trend, and propeptide truncation experiments of the homologous enzyme XynB validated the feasibility of the truncation strategy. This work reveals the role of GH11 family propeptides in functional regulation and provides a straightforward and practical method to increase the robustness of GH11 family xylanases.


Assuntos
Endo-1,4-beta-Xilanases , Simulação de Dinâmica Molecular , Domínio Catalítico , Regulação Alostérica , Temperatura , Endo-1,4-beta-Xilanases/metabolismo , Estabilidade Enzimática
14.
Water Res ; 242: 120273, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37393810

RESUMO

Membrane capacitive deionization (MCDI) is a water desalination technology that involves the removal of charged ions from water under an electric field. While constant-current MCDI coupled with stopped-flow during ion discharge is expected to exhibit high water recovery and good performance stability, previous studies have typically been undertaken using NaCl solutions only with limited investigation of MCDI performance using multi-electrolyte solutions. In the present work, the desalination performance of MCDI was evaluated using feed solutions with different levels of hardness. The increase of hardness resulted in the degradation of desalination performance with the desalination time (Δtd), total removed charge, water recovery (WR) and productivity decreasing by 20.5%, 21.8%, 3.8% and 3.2%, respectively. A more serious degradation of WR and productivity would be caused if Δtd decreases further. Analysis of the voltage profiles and effluent ion concentrations reveal that the insufficient desorption of divalent ions at constant-current discharge to 0 V was the principal reason for the degradation of performance. The Δtd and WR can be improved by discharging the cell using a lower current but the productivity decreased by 15.7% on decreasing the discharging current from 161 to 107 mA. Discharging the cell to a negative potential was shown to be a better option with the Δtd, total removed charge, WR and productivity increasing by 27.4%, 23.9%, 3.6% and 5.3%, respectively, when the cell was discharged to a minimum voltage of - 0.3 V. Use of such a method should be feasible for operation of full scale MCDI plants and would be expected to lead to better regeneration of the electrode, improved desalination performance and, potentially, a significant reduction in the need for use of clean-in-place procedures.


Assuntos
Purificação da Água , Purificação da Água/métodos , Adsorção , Íons , Cloreto de Sódio , Eletrodos , Água
15.
Magn Reson Med ; 90(5): 1919-1931, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37382206

RESUMO

PURPOSE: Although recent convolutional neural network (CNN) methodologies have shown promising results in fast MR imaging, there is still a desire to explore how they can be used to learn the frequency characteristics of multicontrast images and reconstruct texture details. METHODS: A global attention-enabled texture enhancement network (GATE-Net) with a frequency-dependent feature extraction module (FDFEM) and convolution-based global attention module (GAM) is proposed to address the highly under-sampling MR image reconstruction problem. First, FDFEM enables GATE-Net to effectively extract high-frequency features from shareable information of multicontrast images to improve the texture details of reconstructed images. Second, GAM with less computation complexity has the receptive field of the entire image, which can fully explore useful shareable information of multi-contrast images and suppress less beneficial shareable information. RESULTS: The ablation studies are conducted to evaluate the effectiveness of the proposed FDFEM and GAM. Experimental results under various acceleration rates and datasets consistently demonstrate the superiority of GATE-Net, in terms of peak signal-to-noise ratio, structural similarity and normalized mean square error. CONCLUSION: A global attention-enabled texture enhancement network is proposed. it can be applied to multicontrast MR image reconstruction tasks with different acceleration rates and datasets and achieves superior performance in comparison with state-of-the-art methods.


Assuntos
Imageamento por Ressonância Magnética , Redes Neurais de Computação , Imageamento por Ressonância Magnética/métodos , Processamento de Imagem Assistida por Computador/métodos , Encéfalo/diagnóstico por imagem , Razão Sinal-Ruído
16.
Cell Death Dis ; 14(5): 344, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37253771

RESUMO

Cardiac hypertrophy is a common structural remodeling in many cardiovascular diseases. Recently, long non-coding RNAs (LncRNAs) were found to be involved in the physiological and pathological processes of cardiac hypertrophy. In this study, we found that LncRNA KCND1 (LncKCND1) was downregulated in both transverse aortic constriction (TAC)-induced hypertrophic mouse hearts and Angiotensin II (Ang II)-induced neonatal mouse cardiomyocytes. Further analyses showed that the knockdown of LncKCND1 impaired cardiac mitochondrial function and led to hypertrophic changes in cardiomyocytes. In contrast, overexpression of LncKCND1 inhibited Ang II-induced cardiomyocyte hypertrophic changes. Importantly, enhanced expression of LncKCND1 protected the heart from TAC-induced pathological cardiac hypertrophy and improved heart function in TAC mice. Subsequent analyses involving mass spectrometry and RNA immunoprecipitation assays showed that LncKCND1 directly binds to YBX1. Furthermore, overexpression of LncKCND1 upregulated the expression level of YBX1, while silencing LncKCND1 had the opposite effect. Furthermore, YBX1 was downregulated during cardiac hypertrophy, whereas overexpression of YBX1 inhibited Ang II-induced cardiomyocyte hypertrophy. Moreover, silencing YBX1 reversed the effect of LncKCND1 on cardiomyocyte mitochondrial function and its protective role in cardiac hypertrophy, suggesting that YBX1 is a downstream target of LncKCND1 in regulating cardiac hypertrophy. In conclusion, our study provides mechanistic insights into the functioning of LncKCND1 and supports LncKCND1 as a potential therapeutic target for pathological cardiac hypertrophy.


Assuntos
RNA Longo não Codificante , Fatores de Transcrição , Animais , Camundongos , Angiotensina II/farmacologia , Cardiomegalia/metabolismo , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Canais de Potássio Shal/metabolismo , Fatores de Transcrição/metabolismo
17.
Artigo em Inglês | MEDLINE | ID: mdl-36613209

RESUMO

Street trees in urban areas have positive impacts on the environment, such as climate regulation, air purification, and runoff mitigation. However, the ecosystem services (ES) provided by street trees at the parcel level remain a notable gap in the existing literature. This study quantified the ES benefits provided by street trees at Jiangsu University in Zhenjiang, China, which could represent the parcel level. A widely applied model, i-Tree Eco, was used to evaluate the ES, including carbon storage, carbon sequestration, pollutant removal, rainwater runoff reduction, and their economic value. We also analyzed how these are affected by the structure of tree species. The results revealed that the 10 most abundant species accounted for 84.3% of the total number of trees, with an unstable structure of species composition. A reasonable age proportion was important since a lower proportion of young trees may make future benefit outputs unstable. The annual economic value provided by ES was USD 205,253.20, with an average of USD 79.90 per tree. Platanus orientalis had the highest single plant benefit, indicating that the management pattern of street trees could be adapted in different environments to maximize benefits. Thus, street trees at the parcel level should receive more attention with strategic planning and management in order to maximize the ES and their economic value.


Assuntos
Ecossistema , Poluentes Ambientais , Humanos , Árvores , China , Carbono
18.
Environ Sci Pollut Res Int ; 30(7): 18040-18063, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36205866

RESUMO

Land use changes have a considerable impact on ecosystem services (ESs). In recent years, land use changes caused by urban expansion in Nanjing City have been obvious and are expected to further change in the future. Therefore, it is urgent to quantitatively assess ecosystem service value (ESV) changes caused by previous land use changes and future potential changes in Nanjing. In this study, land use data products based on remote sensing images, Dyna-CLUE model, and the ESV equivalent coefficient method were applied to assess the impact of land use changes on ESVs in Nanjing City over the past 23 years (1995-2018), and to forecast the changes of ESV in 2030. The results indicated that the total ESVs of Nanjing City displayed a trend of first increasing and then declining in 1995-2018. From the land use classification, the water area had the largest ESV in Nanjing, followed by arable land. Additionally, the regulating service value was the highest among the four primary ESs in Nanjing from 1995 to 2030, with the highest value of 13.73 billion yuan in 2015. Among the three forecast scenarios, the ecological protection scenario had the highest total ESV and was followed by the urban expansion and business as usual scenarios. These findings may assist for the scientific decision-making of sustainable land use and ecosystem management in Nanjing City.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Cidades , Previsões , China
19.
BMC Geriatr ; 22(1): 971, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36522628

RESUMO

BACKGROUND: Abdominal obesity (AO) has been regarded as the most dangerous type of obesity. The Conicity-index (C-index) had a high ability to discriminate underlying AO. The purpose of this study was to determine the ability of C-index to predict all-cause mortality among non-cancer Chinese older people. METHODS: The participants were residents of the Wanshou Road community in Beijing, China. Receiver operating curve (ROC) curves were used to determine the sensitivity and specificity of the best cut-off values for different anthropometric measures for predicting all-cause mortality. The area under the curve (AUC) of the ROC curves were calculated to compare the relative ability of various anthropometric measures to correctly identify older people in the community where all-cause mortality occurs. Included subjects were grouped according to C-index tertiles. The association between C-index and all-cause mortality was verified using Kaplan-Meier survival analysis and different Cox regression models. RESULTS: During a mean follow-up period of 9.87 years, 1821 subjects completed follow-up. The average age was 71.21 years, of which 59.4% were female. The ROC curve results showed that the AUC of the C-index in predicting all-cause mortality was 0.633. Kaplan-Meier survival curves showed a clear dose-response relationship between C-index and all-cause mortality. With the increase of C-index, the survival rate of the study population showed a significant downward trend (P < 0.05). Adjusted for age, gender, hip circumference, systolic blood pressure, diastolic blood pressure, fasting blood glucose (FBG), 2-h postprandial blood glucose (2hPG), glycosylated hemoglobin, high-density lipids protein (LDL), triglyceride, serum creatinine, serum uric acid, urine albumin-creatinine ratio (UACR), Mini-Mental State Examination (MMSE), smoking history, and drinking history, COX regression analysis showed that in the model adjusted for all covariates, the risk of all-cause mortality in tertile 3 was 1.505 times that in tertile 1, and the difference was statistically significant. CONCLUSIONS: The C-index is an independent risk factor for all-cause mortality in the non-cancer Chinese older people.


Assuntos
Glicemia , Ácido Úrico , Humanos , Feminino , Idoso , Masculino , Seguimentos , População do Leste Asiático , Pressão Sanguínea , Obesidade/epidemiologia , Fatores de Risco , Obesidade Abdominal , Curva ROC , Índice de Massa Corporal
20.
Front Psychol ; 13: 918737, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36160566

RESUMO

In the perceptual learning of lexical tones, an automatic and robust attention-to-phonology system enables native tonal listeners to adapt to acoustically non-optimal speech, such as phonetic conflicts in daily communications. Previous tone research reveals that non-native listeners who do not linguistically employ lexical tones in their mother tongue may find it challenging to attend to the tonal dimension or integrate it with the segmental features. However, it is unknown whether the attentional interference initially caused by a maternal attentional system would continue influencing the non-optimal tone perception for simultaneous bilingual teenagers. From an endpoint in the age of language acquisition, we investigate whether the tone-specific attention mechanism developed by the Urdu-Cantonese simultaneous bilinguals is automatic enough to assist them in adapting to a phonetically-conflicting environment. Three groups of teenagers engaged in a four-condition ABX task: Urdu-Cantonese simultaneous bilinguals, Cantonese native listeners, and Urdu-speaking, late learners of Cantonese. The results showed that although the simultaneous bilinguals could phonologically process Cantonese tones in a Cantonese-like way under a conflict-free listening condition, they still failed in adapting to the phonetic conflicts, especially the segment-induced ones. It thus demonstrated that the simultaneous exposure and years of regular education in Hong Kong local schools still could not automatically guarantee simultaneous bilingual processing of Cantonese tones. In interpreting the findings, it hypothesized that, except for simultaneous exposure, the development of a tone-specific attention mechanism is also likely to be L1-inhibitory, tone experience-driven, and language-specific for simultaneous bilinguals.

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