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1.
Development ; 149(9)2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35552394

RESUMO

In central nervous system vascular endothelial cells, signaling via the partially redundant ligands WNT7A and WNT7B requires two co-activator proteins, GPR124 and RECK. WNT7A and RECK have been shown previously to play a role in limb development, but the mechanism of RECK action in this context is unknown. The roles of WNT7B and GPR124 in limb development have not been investigated. Using combinations of conventional and/or conditional loss-of-function alleles for mouse Wnt7a, Wnt7b, Gpr124 and Reck, including a Reck allele that codes for a protein that is specifically defective in WNT7A/WNT7B signaling, we show that reductions in ligand and/or co-activator function synergize to cause reduced and dysmorphic limb bone growth. Two additional limb phenotypes - loss of distal Lmx1b expression and ectopic growth of nail-like structures - occur with reduced Wnt7a/Wnt7b gene copy number and, respectively, with Reck mutations and with combined Reck and Gpr124 mutations. A third limb phenotype - bleeding into a digit - occurs with the most severe combinations of Wnt7a/Wnt7b, Reck and Gpr124 mutations. These data imply that the WNT7A/WNT7B-FRIZZLED-LRP5/LRP6-GPR124-RECK signaling system functions as an integral unit in limb development.


Assuntos
Embrião de Mamíferos/metabolismo , Extremidades/embriologia , Proteínas Ligadas por GPI/metabolismo , Receptores Acoplados a Proteínas G , Proteínas Wnt , Animais , Sistema Nervoso Central/metabolismo , Células Endoteliais/metabolismo , Ligantes , Camundongos , Proteínas Proto-Oncogênicas/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Proteínas Wnt/genética , Proteínas Wnt/metabolismo
2.
Nature ; 567(7749): 545-549, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30894746

RESUMO

MYC is an oncogenic transcription factor that binds globally to active promoters and promotes transcriptional elongation by RNA polymerase II (RNAPII)1,2. Deregulated expression of the paralogous protein MYCN drives the development of neuronal and neuroendocrine tumours and is often associated with a particularly poor prognosis3. Here we show that, similar to MYC, activation of MYCN in human neuroblastoma cells induces escape of RNAPII from promoters. If the release of RNAPII from transcriptional pause sites (pause release) fails, MYCN recruits BRCA1 to promoter-proximal regions. Recruitment of BRCA1 prevents MYCN-dependent accumulation of stalled RNAPII and enhances transcriptional activation by MYCN. Mechanistically, BRCA1 stabilizes mRNA decapping complexes and enables MYCN to suppress R-loop formation in promoter-proximal regions. Recruitment of BRCA1 requires the ubiquitin-specific protease USP11, which binds specifically to MYCN when MYCN is dephosphorylated at Thr58. USP11, BRCA1 and MYCN stabilize each other on chromatin, preventing proteasomal turnover of MYCN. Because BRCA1 is highly expressed in neuronal progenitor cells during early development4 and MYC is less efficient than MYCN in recruiting BRCA1, our findings indicate that a cell-lineage-specific stress response enables MYCN-driven tumours to cope with deregulated RNAPII function.


Assuntos
Proteína BRCA1/metabolismo , Proteína Proto-Oncogênica N-Myc/metabolismo , RNA Polimerase II/metabolismo , Elongação da Transcrição Genética , Linhagem Celular Tumoral , Cromatina/genética , Cromatina/metabolismo , Regulação da Expressão Gênica , Humanos , Neuroblastoma/genética , Neuroblastoma/patologia , Estabilidade Proteica , Tioléster Hidrolases/metabolismo
3.
Mol Ther ; 32(5): 1479-1496, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429926

RESUMO

Intense inflammatory response impairs bone marrow mesenchymal stem cell (BMSC)-mediated bone regeneration, with transforming growth factor (TGF)-ß1 being the most highly expressed cytokine. However, how to find effective and safe means to improve bone formation impaired by excessive TGF-ß1 remains unclear. In this study, we found that the expression of orphan nuclear receptor Nr4a1, an endogenous repressor of TGF-ß1, was suppressed directly by TGF-ß1-induced Smad3 and indirectly by Hdac4, respectively. Importantly, Nr4a1 overexpression promoted BMSC osteogenesis and reversed TGF-ß1-mediated osteogenic inhibition and pro-fibrotic effects. Transcriptomic and histologic analyses confirmed that upregulation of Nr4a1 increased the transcription of Wnt family member 4 (Wnt4) and activated Wnt pathway. Mechanistically, Nr4a1 bound to the promoter of Wnt4 and regulated its expression, thereby enhancing the osteogenic capacity of BMSCs. Moreover, treatment with Nr4a1 gene therapy or Nr4a1 agonist Csn-B could promote ectopic bone formation, defect repair, and fracture healing. Finally, we demonstrated the correlation of NR4A1 with osteogenesis and the activation of the WNT4/ß-catenin pathway in human BMSCs and fracture samples. Taken together, these findings uncover the critical role of Nr4a1 in bone formation and alleviation of inflammation-induced bone regeneration disorders, and suggest that Nr4a1 has the potential to be a therapeutic target for accelerating bone healing.


Assuntos
Regeneração Óssea , Inflamação , Células-Tronco Mesenquimais , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Osteogênese , Proteína Wnt4 , Células-Tronco Mesenquimais/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Osteogênese/genética , Regeneração Óssea/genética , Animais , Camundongos , Proteína Wnt4/metabolismo , Proteína Wnt4/genética , Humanos , Inflamação/genética , Inflamação/metabolismo , Regulação da Expressão Gênica , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/genética , Via de Sinalização Wnt , Masculino , Transcrição Gênica , Histona Desacetilases/metabolismo , Histona Desacetilases/genética , Modelos Animais de Doenças
4.
J Am Chem Soc ; 146(22): 15320-15330, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38683738

RESUMO

Palladium hydrides (PdHx) are pivotal in both fundamental research and practical applications across a wide spectrum. PdHx nanocrystals, synthesized by heating in dimethylformamide (DMF), exhibit remarkable stability, granting them widespread applications in the field of electrocatalysis. However, this stability appears inconsistent with their metastable nature. The substantial challenges in characterizing nanoscale structures contribute to the limited understanding of this anomalous phenomenon. Here, through a series of well-conceived experimental designs and advanced characterization techniques, including aberration-corrected scanning transmission electron microscopy (AC-STEM), in situ X-ray diffraction (XRD), and time-of-flight secondary ion mass spectrometry (TOF-SIMS), we have uncovered evidence that indicates the presence of C and N within the lattice of Pd (PdCxNy), rather than H (PdHx). By combining theoretical calculations, we have thoroughly studied the potential configurations and thermodynamic stability of PdCxNy, demonstrating a 2.5:1 ratio of C to N infiltration into the Pd lattice. Furthermore, we successfully modulated the electronic structure of Pd nanocrystals through C and N doping, enhancing their catalytic activity in methanol oxidation reactions. This breakthrough provides a new perspective on the structure and composition of Pd-based nanocrystals infused with light elements, paving the way for the development of advanced catalytic materials in the future.

5.
Stem Cells ; 41(9): 862-876, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37317792

RESUMO

Numerous intrinsic factors regulate mesenchymal progenitor commitment to a specific cell fate, such as osteogenic or adipogenic lineages. Identification and modulation of novel intrinsic regulatory factors represent an opportunity to harness the regenerative potential of mesenchymal progenitors. In the present study, the transcription factor (TF) ZIC1 was identified to be differentially expressed among adipose compared with skeletal-derived mesenchymal progenitor cells. We observed that ZIC1 overexpression in human mesenchymal progenitors promotes osteogenesis and prevents adipogenesis. ZIC1 knockdown demonstrated the converse effects on cell differentiation. ZIC1 misexpression was associated with altered Hedgehog signaling, and the Hedgehog antagonist cyclopamine reversed the osteo/adipogenic differentiation alterations associated with ZIC1 overexpression. Finally, human mesenchymal progenitor cells with or without ZIC1 overexpression were implanted in an ossicle assay in NOD-SCID gamma mice. ZIC1 overexpression led to significantly increased ossicle formation in comparison to the control, as assessed by radiographic and histologic measures. Together, these data suggest that ZIC1 represents a TF at the center of osteo/adipogenic cell fate determinations-findings that have relevance in the fields of stem cell biology and therapeutic regenerative medicine.


Assuntos
Adipogenia , Células-Tronco Mesenquimais , Animais , Camundongos , Humanos , Adipogenia/genética , Proteínas Hedgehog , Osteogênese/fisiologia , Camundongos Endogâmicos NOD , Camundongos SCID , Diferenciação Celular , Fatores de Transcrição/genética
6.
BMC Musculoskelet Disord ; 25(1): 601, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080620

RESUMO

BACKGROUND: This study aimed to investigate functions of GLP-1R agonist by liraglutide (LIRA) and revealing the mechanism related to AGEs/RAGE in chondrocytes. METHODS: To illustrate potential effect of GLP-1R agonist on AGEs induced chondrocytes, chondrocytes were administrated by AGEs with LIRA and GLP-1R inhibitor exendin. Inflammatory factors were assessed using ELISA. Real-time PCR was used to evaluate the catabolic activity MMPs and ADAMTS mRNA level, as well as anabolic activity (aggrecan and collagen II). RAGE expression was investigated by Western blotting. TUNEL, caspase3 activity and immunofluorescence were performed to test the apoptotic activity. RESULTS: Our results showed that treatment with LIRA at > 100 nM attenuated the AGE-induced chondrocyte viability. Western bolt demonstrated that GLP-1R activation by LIRA treatment reduced RAGE protein expression compared with the AGEs groups. ELISA showed that LIRA hindered the AGEs-induced production of inflammatory cytokines (IL-6, IL-12 and TNF-α) in primary chondrocytes. AGEs induced catabolism levels (MMP-1, -3, -13 and ADAMTS-4, 5) are also attenuated by LIRA, causing the retention of more extracellular matrix (Aggrecan and Collagen II). TUNEL, caspase3 activity and immunofluorescence results indicated that LIRA inhibited the AGEs-induced production of inflammatory cytokines in primary chondrocytes and attenuated the caspase 3 level, leading to the reduced apoptotic activity. All the protective effects are reversed by exendin (GLP-1R blockers). CONCLUSIONS: The present study demonstrates for the first time that LIRA, an agonist for GLP-1R which is commonly used in type 2 diabetes reverses AGEs induced chondrocyte inflammation and apoptosis through suppressing RAGE signaling, contributing to reduced catabolism and retention of more extracellular matrix. The above results indicate the possible effect of GLP-1R agonist on treating OA.


Assuntos
Apoptose , Condrócitos , Receptor do Peptídeo Semelhante ao Glucagon 1 , Produtos Finais de Glicação Avançada , Inflamação , Liraglutida , Receptor para Produtos Finais de Glicação Avançada , Transdução de Sinais , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Condrócitos/patologia , Liraglutida/farmacologia , Produtos Finais de Glicação Avançada/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Apoptose/efeitos dos fármacos , Animais , Transdução de Sinais/efeitos dos fármacos , Inflamação/metabolismo , Inflamação/tratamento farmacológico , Inflamação/patologia , Células Cultivadas
7.
BMC Nurs ; 23(1): 648, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39267008

RESUMO

BACKGROUND: A positive work environment can enhance nursing safety and patient satisfaction while alleviating nurse stress. Conversely, a poor work environment can harm nurses' physical and mental health and compromise the quality of care, particularly in the high-intensity and shift-based setting of the ICU. OBJECTIVES: Based on the Job demands-resources (JD-R) model, this study examined the effects of job demands and job resources in the work environment, as well as personal resources, on the night-shift alertness of ICU shift nurses. METHODS: This cross-sectional correlational exploratory study, conducted from July to September 2022, recruited 291 ICU shift nurses from a hospital in Beijing, China. The Copenhagen Psychosocial Questionnaire (COPSOQ), the Self-resilience scale, the General Self-Efficacy Scale (GSES), and the Psychomotor Vigilance Task (PVT) were used to subjectively and objectively measure the job demands, job resources, personal resources, and night-shift alertness. SPSS 26.0 and Mplus 8.3 were used to analyze the data and construct the structural equation model. RESULTS: The night-shift reaction time was 251.0 ms (Median), indicating a relatively high level of alertness. Job demands were negatively correlated with both job resources (r=-0.570, P < 0.001) and personal resources (r=-0.462, P < 0.001), while a positive correlation existed between job resources and personal resources (r = 0.554, P < 0.001). The results show that increased job demands can lead to higher levels of nurse strain (ß = 0.955, P < 0.001), whereas job resources were found that it can decrease strain (ß=-0.477, P = 0.047). Adequate job resources can enhance motivation directly (ß = 0.874, P < 0.001), subsequently reducing reaction time (ß=-0.148, P = 0.044) and improving night-shift alertness among ICU shift nurses. CONCLUSION: Enhancing ICU shift nurses' work motivation through bolstering job resources can boost night-shift alertness. However, it is noteworthy that, in this study, neither strain nor individual resources significantly influenced nurses' night-shift alertness. This may be attributed to the complexity of the ICU environment and individual differences. Future research should explore the relationship between these factors and nurses' work alertness.

8.
BMC Nurs ; 23(1): 54, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38238706

RESUMO

BACKGROUND: China is experiencing an aging population, leading to a significant demand for "Internet + nursing services" tailored for elderly individuals. However, there are many risk problems in the process of nurse service, which hinder the development of the service, and a scale is needed to assess the risk problems faced by nurses in "Internet + nursing services" for the elderly. OBJECTIVE: The purpose of this study is to develop an assessment scale for risk factors and outcomes related to nurses' involvement in the "Internet + Nursing Service" for the elderly and to assess its reliability and validity. METHODS: Based on literature analysis, focus group, the Delphi method, and a presurvey, we designed an initial scale. The initial scale comprised two sections: risk factors and risk outcomes for nurses. In January and February of 2023, nurses engaged in "Internet + nursing services" for the elderly in Shanxi Province were chosen through a convenience sampling technique for a questionnaire survey. Subsequently, item analysis and exploratory factor analysis were employed to refine and develop a test version of the scale further. A follow-up questionnaire survey was carried out in March and April 2023 using a similar approach. The reliability and validity of the scale were assessed through confirmatory factor analysis, culminating in the formation of the final scale. RESULTS: The initial survey yielded 244 valid responses. The cumulative variance contributions of the two segments from the exploratory factor analysis were 84.584% and 90.089%, respectively. A subsequent survey garnered 220 valid responses. The confirmatory factor analysis results indicated: χ2/df = 2.086, comparative fit index (CFI) = 0.918, normative fit index (NLI) = 0.855, root mean square of residuals (RMR) = 0.045, and root mean square of error of approximation (RMSEA) = 0.070. These results demonstrate good structural, convergent, and discriminant validity. The content validity index at the item level (I-CVI) ranged between 0.875 and 1.000, while the content validity index at the scale level (S-CVI/Ave) was 0.941. Cronbach's alpha coefficient for the entire scale stood at 0.970. Moreover, the scale exhibited a split-half reliability of 0.876 and a retest reliability of 0.980 (p < 0.01). CONCLUSION: The risk factors and risk outcomes associated with nurses involved in "Internet + nursing services" for elderly individuals, as developed in this study, demonstrate strong reliability and validity. They are well suited to the Chinese national context.

9.
Water Sci Technol ; 89(12): 3163-3177, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39150418

RESUMO

Anaerobic co-digestion was conducted on the solid residues after three-phase separation of kitchen waste (KWS) and waste-activated sludge (WAS), the synergistic effects and process performance were studied during co-digestion at different ratios of KWS to WAS. KWS and WAS mix ratios of 0:1, 1:4, 1:3, 1:2, 1:1, 2:1, 3:1, 4:1 and 1:0 (based on TS). The results showed that a ratio of KWS to WAS of 1:1 got a very high methane recovery with a methane yield of 310.45 ± 30.05 mL/g VSadded. The highest concentration of free ammonia among all reaction systems was only 70.23 ± 5.53 mg/L, which was not enough to produce ammonia inhibition in the anaerobic co-digestion system. However, when the KWS content exceeded 50%, methane inhibition and prolongation of the lag phase were observed due to the accumulation of volatile fatty acids (VFAs), and during the lag phase. Microbial community analysis showed that various bacterial groups involved in acid production and hydrolysis were mainly dominated by phylum Firmicutes, Chloroflexi, Proteobacteria and Bacteroidetes. Hydrogenotrophic methanogen was found to dominate all archaeal communities in the digesters. Co-digestion of KWS with WAS significantly increased the relative abundance of Methanobacterium compared with anaerobic digestion of WAS alone.


Assuntos
Reatores Biológicos , Metano , Esgotos , Esgotos/microbiologia , Anaerobiose , Metano/metabolismo , Bactérias/metabolismo , Bactérias/classificação , Amônia/metabolismo , Eliminação de Resíduos/métodos , Resíduos Sólidos , Eliminação de Resíduos Líquidos/métodos , Resíduos de Alimentos
10.
Angew Chem Int Ed Engl ; 63(20): e202403114, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38488787

RESUMO

The conversion of methane under ambient conditions has attracted significant attention. Although advancements have been made using active oxygen species from photo- and electro- chemical processes, challenges such as complex catalyst design, costly oxidants, and unwanted byproducts remain. This study exploits the concept of contact-electro-catalysis, initiating chemical reactions through charge exchange at a solid-liquid interface, to report a novel process for directly converting methane under ambient conditions. Utilizing the electrification of commercially available Fluorinated Ethylene Propylene (FEP) with water under ultrasound, we demonstrate how this interaction promote the activation of methane and oxygen molecules. Our results show that the yield of HCHO and CH3OH can reach 467.5 and 151.2 µmol ⋅ gcat -1, respectively. We utilized electron paramagnetic resonance (EPR) to confirm the evolution of hydroxyl radicals (⋅OH) and superoxide radicals (⋅OOH). Isotope mass spectrometry (MS) was employed to analyze the elemental origin of CH3OH, which can be further oxidized to HCHO. Additionally, we conducted density functional theory (DFT) simulations to assess the reaction energies of FEP with H2O, O2, and CH4 under these conditions. The implications of this methodology, with its potential applicability to a wider array of gas-phase catalytic reactions, underscore a significant advance in catalysis.

11.
Mol Cancer ; 22(1): 16, 2023 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-36691031

RESUMO

BACKGROUND: hsa_circ_0001727 (circZKSCAN1) has been reported to be a tumor-associated circRNA by sponging microRNAs. Intriguingly, we found that circZKSCAN1 encoded a secretory peptide (circZKSaa) in the liver. The present study aims to elucidate the potential role and molecular mechanism of circZKSaa in the regulation of hepatocellular carcinoma (HCC) progression. METHODS: The circRNA profiling datasets (RNA-seq data GSE143233 and GSE140202) were reanalyzed and circZKSCAN1 was selected for further study. Mass spectrometry, polysome fractionation assay, dual-luciferase reporter, and a series of experiments showed that circZKSCAN1 encodes circZKSaa. Cell proliferation, apoptosis, and tumorigenesis in nude mice were examined to investigate the functions of circZKSaa. Mechanistically, the relationship between the circZKSaa and mTOR in HCC was verified by immunoprecipitation analyses, mass spectrometry, and immunofluorescence staining analyses. RESULTS: Receiver operating characteristic (ROC) analysis demonstrated that the secretory peptide circZKSaa encoded by circZKSCAN1 might be the potential biomarker for HCC tissues. Through a series of experiments, we found that circZKSaa inhibited HCC progression and sensitize HCC cells to sorafenib. Mechanistically, we found that the sponge function of circZKSCAN1 to microRNA is weak in HCC, while overexpression of circZKSaa promoted the interaction of FBXW7 with the mammalian target of rapamycin (mTOR) to promote the ubiquitination of mTOR, thereby inhibiting the PI3K/AKT/mTOR pathway. Furthermore, we found that the high expression of cicZKSCAN1 in sorafenib-treated HCC cells was regulated by QKI-5. CONCLUSIONS: These results reveal that a novel circZKSCAN1-encoded peptide acts as a tumor suppressor on PI3K/AKT/mTOR pathway, and sensitizes HCC cells to sorafenib via ubiquitination of mTOR. These findings demonstrated that circZKSaa has the potential to serve as a therapeutic target and biomarker for HCC treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Animais , Camundongos , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , Mamíferos/genética , Mamíferos/metabolismo , Camundongos Nus , MicroRNAs/genética , Peptídeos/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Circular/genética , Sirolimo , Sorafenibe , Serina-Treonina Quinases TOR/metabolismo , Humanos
12.
Cell Tissue Res ; 391(3): 425-440, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36645476

RESUMO

Induced pluripotent stem cells (iPS cells) are considered a promising source of cell-based therapy for the treatment of Parkinson's disease (PD). Recent studies have shown forebrain GABA interneurons have crucial roles in many psychiatric disorders, and secondary changes in the GABA system play a directly effect on the pathogenesis of PD. Here, we first describe an efficient differentiation procedure of GABA progenitors (MiPSC-iGABAPs) from miniature-swine iPSCs through two major developmental stages. Then, the MiPSC-iGABAPs were stereotactically transplanted into the right medial forebrain bundle (MFB) of 6-hydroxydopamine (OHDA)-lesioned PD model rats to confirm their feasibility for the neural transplantation as a donor material. Furthermore, the grafted MiPSC-iGABAPs could survive and migrate from the graft site into the surrounding brain tissue including striatum (ST) and substantia nigra (SN) for at least 32 weeks, and significantly improved functional recovery of PD rats from their parkinsonian behavioral defects. Histological studies showed that the grafted cells could migrate and differentiate into various neurocytes, including GABAergic, dopaminergic neurons, and glial cells in vivo, and many induced dopaminergic neurons extended dense neurites into the host striatum. Moreover, over 50% of the grafted MiPSC-iGABAPs could express GABA, and these GABAergic neurons might be responsible for modifying the balance of excitatory and inhibitory signals in the striatum to promote behavioral recovery. Thus, the present study confirmed that the MiPSC-iGABAPs can be used as an attractive donor material for the neural grafting to remodel basal ganglia circuitry in neurodegenerative diseases, avoiding tumorigenicity of iPSCs and the nonproliferative and nondifferentiated potential of mature neurons.


Assuntos
Células-Tronco Pluripotentes Induzidas , Doença de Parkinson , Transtornos Parkinsonianos , Suínos , Ratos , Animais , Doença de Parkinson/patologia , Porco Miniatura , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/terapia , Neurônios Dopaminérgicos/patologia , Neurônios GABAérgicos , Corpo Estriado/patologia , Ácido gama-Aminobutírico , Modelos Animais de Doenças
13.
Eur Radiol ; 33(12): 8585-8596, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37382615

RESUMO

OBJECTIVES: To evaluate the image quality and diagnostic performance of AI-assisted compressed sensing (ACS) accelerated two-dimensional fast spin-echo MRI compared with standard parallel imaging (PI) in clinical 3.0T rapid knee scans. METHODS: This prospective study enrolled 130 consecutive participants between March and September 2022. The MRI scan procedure included one 8.0-min PI protocol and two ACS protocols (3.5 min and 2.0 min). Quantitative image quality assessments were performed by evaluating edge rise distance (ERD) and signal-to-noise ratio (SNR). Shapiro-Wilk tests were performed and investigated by the Friedman test and post hoc analyses. Three radiologists independently evaluated structural disorders for each participant. Fleiss κ analysis was used to compare inter-reader and inter-protocol agreements. The diagnostic performance of each protocol was investigated and compared by DeLong's test. The threshold for statistical significance was set at p  < 0.05. RESULTS: A total of 150 knee MRI examinations constituted the study cohort. For the quantitative assessment of four conventional sequences with ACS protocols, SNR improved significantly (p < 0.001), and ERD was significantly reduced or equivalent to the PI protocol. For the abnormality evaluated, the intraclass correlation coefficient ranged from moderate to substantial between readers (κ = 0.75-0.98) and between protocols (κ = 0.73-0.98). For meniscal tears, cruciate ligament tears, and cartilage defects, the diagnostic performance of ACS protocols was considered equivalent to PI protocol (Delong test, p > 0.05). CONCLUSIONS: Compared with the conventional PI acquisition, the novel ACS protocol demonstrated superior image quality and was feasible for achieving equivalent detection of structural abnormalities while reducing acquisition time by half. CLINICAL RELEVANCE STATEMENT: Artificial intelligence-assisted compressed sensing (ACS) providing excellent quality and a 75% reduction in scanning time presents significant clinical advantages in improving the efficiency and accessibility of knee MRI for more patients. KEY POINTS: • The prospective multi-reader study showed no difference in diagnostic performance between parallel imaging and AI-assisted compression sensing (ACS) was found. • Reduced scan time, sharper delineation, and less noise with ACS reconstruction. • Improved efficiency of the clinical knee MRI examination by the ACS acceleration.


Assuntos
Inteligência Artificial , Traumatismos do Joelho , Humanos , Estudos Prospectivos , Estudos de Viabilidade , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Traumatismos do Joelho/diagnóstico por imagem
14.
Eur Radiol ; 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37932390

RESUMO

OBJECTIVE: To investigate the potential applicability of AI-assisted compressed sensing (ACS) in knee MRI to enhance and optimize the scanning process. METHODS: Volunteers and patients with sports-related injuries underwent prospective MRI scans with a range of acceleration techniques. The volunteers were subjected to varied ACS acceleration levels to ascertain the most effective level. Patients underwent scans at the determined optimal 3D-ACS acceleration level, and 3D compressed sensing (CS) and 2D parallel acquisition technology (PAT) scans were performed. The resultant 3D-ACS images underwent 3.5 mm/2.0 mm multiplanar reconstruction (MPR). Experienced radiologists evaluated and compared the quality of images obtained by 3D-ACS-MRI and 3D-CS-MRI, 3.5 mm/2.0 mm MPR and 2D-PAT-MRI, diagnosed diseases, and compared the results with the arthroscopic findings. The diagnostic agreement was evaluated using Cohen's kappa correlation coefficient, and both absolute and relative evaluation methods were utilized for objective assessment. RESULTS: The study involved 15 volunteers and 53 patients. An acceleration factor of 10.69 × was identified as optimal. The quality evaluation showed that 3D-ACS provided poorer bone structure visualization, and improved cartilage visualization and less satisfactory axial images with 3.5 mm/2.0 mm MPR than 2D-PAT. In terms of objective evaluation, the relative evaluation yielded satisfactory results across different groups, while the absolute evaluation revealed significant variances in most features. Nevertheless, high levels of diagnostic agreement (κ: 0.81-0.94) and accuracy (0.83-0.98) were observed across all diagnoses. CONCLUSION: ACS technology presents significant potential as a replacement for traditional CS in 3D-MRI knee scans, allowing thinner MPRs and markedly faster scans without sacrificing diagnostic accuracy. CLINICAL RELEVANCE STATEMENT: 3D-ACS-MRI of the knee can be completed in the 160 s with good diagnostic consistency and image quality. 3D-MRI-MPR can replace 2D-MRI and reconstruct images with thinner slices, which helps to optimize the current MRI examination process and shorten scanning time. KEY POINTS: • AI-assisted compressed sensing technology can reduce knee MRI scan time by over 50%. • 3D AI-assisted compressed sensing MRI and related multiplanar reconstruction can replace traditional accelerated MRI and yield thinner 2D multiplanar reconstructions. • Successful application of 3D AI-assisted compressed sensing MRI can help optimize the current knee MRI process.

15.
Mol Biol Rep ; 51(1): 39, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38158445

RESUMO

BACKGROUND: Muscone is a chemical monomer derived from musk. Although many studies have confirmed the cardioprotective effects of muscone, the effects of muscone on cardiac hypertrophy and its potential mechanisms are unclear.The aim of the present study was to investigate the effect of muscone on angiotensin (Ang) II-induced cardiac hypertrophy. METHODS AND RESULTS: In the present study, we found for the first time that muscone exerted inhibitory effects on Ang II-induced cardiac hypertrophy and cardiac injury in mice. Cardiac function was analyzed by echocardiography measurement, and the degree of cardiac fibrosis was determined by the quantitative real-time polymerase chain reaction (qRT-PCR), Masson trichrome staining and western blot assay. Secondly, qRT-PCR experiment showed that muscone attenuated cardiac injury by reducing the secretion of pro-inflammatory cytokines and promoting the secretion of anti-inflammatory cytokines. Moreover, western blot analysis found that muscone exerted cardio-protective effects by inhibiting phosphorylation of key proteins in the STAT3, MAPK and TGF-ß/SMAD pathways. In addition, CCK-8 and determination of serum biochemical indexes showed that no significant toxicity or side effects of muscone on normal cells and organs. CONCLUSIONS: Muscone could attenuate Ang II-induced cardiac hypertrophy, in part, by inhibiting the STAT3, MAPK, and TGF-ß/SMAD signaling pathways.


Assuntos
Traumatismos Cardíacos , Transdução de Sinais , Camundongos , Animais , Angiotensina II , Fator de Crescimento Transformador beta/metabolismo , Citocinas/metabolismo , Fibrose , Cardiomegalia/induzido quimicamente
16.
BMC Public Health ; 23(1): 574, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36978067

RESUMO

BACKGROUND: Probiotics have been deemed multipotent and unprecedentedly applied in the health field recently. However, there are challenges in promoting credible and reliable resources while avoiding misinformation regarding probiotics for the public. METHODS: This study analysed 400 eligible probiotic-related videos selected from YouTube, and the three most popular video-sharing platforms (Bilibili, Weibo and TikTok) in China. Video retrieval was performed on September 5th, 2022. GQS and tailored DISCERN tool assess each video's quality, usage, and reliability. A comparative analysis of videos from different sources was carried out. RESULTS: The identity distribution of probiotic video-producers was predominantly experts (n = 202, 50.50%), followed by amateurs (n = 161, 40.25%) and health-related institutions (n = 37, 9.25%). The videos' content category mainly discussed the function of probiotics (n = 120, 30%), the way to choose suitable products (n = 81, 20.25%), and the methods for taking probiotics (n = 71, 17.75%).The overall quality of videos was moderate (3/5 point) assessed by GQS, while the usage (1/6 point) and reliability (2/5 point) detailing probiotics assessed by tailored DISCERN tool were poor. The attitude of probiotic video-producers was primarily positive (n = 323, 80.75%), followed by neutral (n = 52, 13.00%) and negative (n = 25, 6.25%) (P < 0.001). CONCLUSIONS: The current study showed that videos on social media platforms publicise important information including the concepts, usage, and precautions of probiotics to the public. But the overall quality of uploaded videos about probiotics was unsatisfactory. More efforts are needed to improve the higher-quality content of probiotic-related online videos and better propagate probiotic knowledge to the public in the future.


Assuntos
Meios de Comunicação , Probióticos , Mídias Sociais , Humanos , Reprodutibilidade dos Testes , China , Gravação em Vídeo , Disseminação de Informação
17.
J Environ Manage ; 327: 116899, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36459781

RESUMO

Anaerobic digestion (AD) is a promising technology to treat waste-activated sludge, previous study proved that methane production could be enhanced with the addition of choline, this work aimed to solve the problem of rapid biodegradability of choline in the AD process by changing its dosing method. With 0.75 g/L as the optimal choline dosing concentration, experimental results showed that successive choline dosing during the first 3-6 days of AD (experimental groups, EGs) performed better than the single dosing. The accumulative biogas production in EGs was increased by 35.55-36.73%, which could be caused by the simultaneous promotion of hydrolysis-acidification and methanogenesis processes. Especially, the electron exchange capacity of digested sludge in EGs was increased by 16.71-34.58%. In addition, the surface Gibbs free energy (△GSL) of sludge in EGs was 105.51-172.21% higher (corresponding to stronger hydrophilicity and repulsion), which might help disperse sludge flocs and improve mass transfer efficiency, and the △GSL values were positively correlated with the accumulative methane production (R2 = 0.7029). Microbiological analysis showed that microbial communities in EGs were richer and Methanosaeta was regarded as the dominant species with 15.93-30.08% higher relative abundance with choline addition. According to Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, EGs were found to be more active in metabolism clusters. Collectively, these findings demonstrated that successive choline dosing during the first 3-6 days is an effective and novel method to enhance methane production in AD process.


Assuntos
Microbiota , Esgotos , Anaerobiose , Eliminação de Resíduos Líquidos/métodos , Metano , Reatores Biológicos/microbiologia , Interações Hidrofóbicas e Hidrofílicas
18.
Angew Chem Int Ed Engl ; 62(21): e202300604, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36949023

RESUMO

Hydrogen peroxide (H2 O2 ) is an indispensable basic reagent in various industries, such as textile bleach, chemical synthesis, and environmental protection. However, it is challenging to prepare H2 O2 in a green, safe, simple and efficient way under ambient conditions. Here, we found that H2 O2 could be synthesized using a catalytic pathway only by contact charging a two-phase interface at room temperature and normal pressure. Particularly, under the action of mechanical force, electron transfer occurs during physical contact between polytetrafluoroethylene particles and deionized water/O2 interfaces, inducing the generation of reactive free radicals (⋅OH and ⋅O2 - ), and the free radicals could react to form H2 O2 , yielding as high as 313 µmol L-1 h-1 . In addition, the new reaction device could show long-term stable H2 O2 production. This work provides a novel method for the efficient preparation of H2 O2 , which may also stimulate further explorations on contact-electrification-induced chemistry process.

19.
Infect Immun ; 90(9): e0023922, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35938858

RESUMO

Nitrate metabolism is an adaptation mechanism used by many bacteria for survival in anaerobic environments. As a by-product of inflammation, nitrate is used by the intestinal bacterial pathogens to enable gut infection. However, the responses of bacterial respiratory pathogens to nitrate are less well understood. Actinobacillus pleuropneumoniae is an important bacterial respiratory pathogen of swine. Previous studies have suggested that adaptation of A. pleuropneumoniae to anaerobiosis is important for infection. In this work, A. pleuropneumoniae growth and pathogenesis in response to the nitrate were investigated. Nitrate significantly promoted A. pleuropneumoniae growth under anaerobic conditions in vitro and lethality in mice. By using narQ and narP deletion mutants and single-residue-mutated complementary strains of ΔnarQ, the two-component system NarQ/P was confirmed to be critical for nitrate-induced growth, with Arg50 in NarQ as an essential functional residue. Transcriptome analysis showed that nitrate upregulated multiple energy-generating pathways, including nitrate metabolism, mannose and pentose metabolism, and glycerolipid metabolism via the regulation of NarQ/P. Furthermore, narQ, narP, and its target gene encoding the nitrate reductase Nap contributed to the pathogenicity of A. pleuropneumoniae. The Nap inhibitor tungstate significantly reduced the survival of A. pleuropneumoniae in vivo, suggesting that Nap is a potential drug target. These results give new insights into how the respiratory pathogen A. pleuropneumoniae utilizes the alternative electron acceptor nitrate to overcome the hypoxia microenvironment, which can occur in the inflammatory or necrotic infected tissues.


Assuntos
Infecções por Actinobacillus , Actinobacillus pleuropneumoniae , Actinobacillus pleuropneumoniae/genética , Actinobacillus pleuropneumoniae/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Manose/metabolismo , Camundongos , Nitrato Redutases/genética , Nitrato Redutases/metabolismo , Nitratos/metabolismo , Pentoses/metabolismo , Suínos , Virulência
20.
Stem Cells ; 39(11): 1427-1434, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34252260

RESUMO

Mesenchymal progenitor cells are broadly distributed across perivascular niches-an observation conserved between species. One common histologic zone with a high frequency of mesenchymal progenitor cells within mammalian tissues is the tunica adventitia, the outer layer of blood vessel walls populated by cells with a fibroblastic morphology. The diversity and functions of (re)generative cells present in this outermost perivascular niche are under intense investigation; we have reviewed herein our current knowledge of adventitial cell potential with a somewhat narrow focus on bone formation. Antigens of interest to functionally segregate adventicytes are discussed, including CD10, CD107a, aldehyde dehydrogenase isoforms, and CD140a, among others. Purified adventicytes (such as CD10+ , CD107alow , and CD140a+ cells) have stronger osteogenic potential and promote bone formation in vivo. Recent bone tissue engineering applications of adventitial cells are also presented. A better understanding of perivascular progenitor cell subsets may represent a beneficial advance for future efforts in tissue repair and bioengineering.


Assuntos
Células-Tronco Mesenquimais , Pericitos , Animais , Diferenciação Celular , Mamíferos , Osteogênese , Engenharia Tecidual , Cicatrização
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