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1.
FASEB J ; 37(12): e23268, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37889798

RESUMO

As a non-essential amino acid, cysteine could be obtained through both exogenous uptake and endogenous de novo synthesis pathways. Research has demonstrated that restricting the uptake of cystine could result in a depletion of intracellular cysteine and glutathione, ultimately leading to an increase in intracellular reactive oxygen species (ROS) levels. However, the role of methionine in regulating intracellular ROS levels is currently unclear. Here, we want to explore the role of methionine in regulating intracellular ROS levels. We found that methionine restriction could lead to a decrease in intracellular ROS levels, while supplementation with SAM can restore these levels through flow cytometry. Mechanically, we found that the methionine-SAM axis relies on CBS when regulating intracellular ROS levels. Furthermore, we speculate and prove that the methionine-SAM-CBS axis alters the metabolism of serine, thereby reducing intracellular reductive power, therefore promoting intracellular ROS levels through changing metabolite levels and genetic methods. Finally, our study revealed that high expression of CBS in tumor cells could lead to increased intracellular ROS levels, ultimately resulting in faster proliferation rates. Together, our study confirmed that methionine plays a promoting role in the regulation of intracellular ROS levels.


Assuntos
Cisteína , Metionina , Metionina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Serina , S-Adenosilmetionina , Racemetionina
2.
Bioorg Chem ; 146: 107245, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38484587

RESUMO

The overuse of antibiotics has led to the enhanced resistance of many pathogenic bacteria, posing a threat to human health. Therefore, there is a need to develop green and safe alternatives to antibiotics. Beta-defensins play a crucial role in host defense against pathogens and have multifunctional properties, exerting key roles in innate and adaptive immunity, as well as non-immune processes. In this study, a 210 bp long cDNA sequence of yak DEFB114 gene was amplified and successfully expressed in a prokaryotic system. The DEFB114 protein exhibited significant inhibitory effects on the growth of Aspergillus fumigatus in vitro. When co-cultured with yak macrophages, DEFB114 protein enhanced macrophage phagocytic activity and increased nucleic acid fluorescence intensity (P < 0.05). DEFB114 protein also enhanced the activity of yak macrophages stimulated by inactivated Aspergillus fumigatus spores, increased the release of nitric oxide (NO), and promoted the expression of genes such as γ-actin, Lgals, Man2b, and Capg (P < 0.05). In mice experiments, DEFB114 protein promoted resistance against Aspergillus fumigatus infection, by regulating the NOD1/2-ATG16L1-NF-κB pathway to modulate the host immune response and exert its anti-infective effects. In summary, the yak DEFB114 protein could inhibit the growth of Aspergillus fumigatus and enhance the animal's resistance to pathogenic microorganisms, thereby having significant implications in the treatment and prevention of fungal infections.


Assuntos
Aspergilose , NF-kappa B , Animais , Camundongos , Antibacterianos , Aspergilose/tratamento farmacológico , Aspergillus fumigatus , Proteínas Relacionadas à Autofagia/metabolismo , NF-kappa B/metabolismo , Proteína Adaptadora de Sinalização NOD1/metabolismo , Transdução de Sinais
3.
Molecules ; 28(22)2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-38005265

RESUMO

ß-carotene is known to have pharmacological effects such as anti-inflammatory, antioxidant, and anti-tumor properties. However, its main mechanism and related signaling pathways in the treatment of inflammation are still unclear. In this study, component target prediction was performed by using literature retrieval and the SwissTargetPrediction database. Disease targets were collected from various databases, including DisGeNET, OMIM, Drug Bank, and GeneCards. A protein-protein interaction (PPI) network was constructed, and enrichment analysis of gene ontology and biological pathways was carried out for important targets. The analysis showed that there were 191 unique targets of ß-carotene after removing repeat sites. A total of 2067 targets from the three databases were integrated, 58 duplicate targets were removed, and 2009 potential disease action targets were obtained. Biological function enrichment analysis revealed 284 biological process (BP) entries, 31 cellular component (CC) entries, 55 molecular function (MF) entries, and 84 cellular pathways. The biological processes were mostly associated with various pathways and their regulation, whereas the cell components were mainly membrane components. The main molecular functions included RNA polymerase II transcription factor activity, DNA binding specific to the ligand activation sequence, DNA binding, steroid binding sequence-specific DNA binding, enzyme binding, and steroid hormone receptors. The pathways involved in the process included the TNF signaling pathway, sphingomyelin signaling pathway, and some disease pathways. Lastly, the anti-inflammatory signaling pathway of ß-carotene was systematically analyzed using network pharmacology, while the molecular mechanism of ß-carotene was further explored by molecular docking. In this study, the anti-inflammatory mechanism of ß-carotene was preliminarily explored and predicted by bioinformatics methods, and further experiments will be designed to verify and confirm the predicted results, in order to finally reveal the anti-inflammatory mechanism of ß-carotene.


Assuntos
Medicamentos de Ervas Chinesas , beta Caroteno , Farmacologia em Rede , Simulação de Acoplamento Molecular , Anti-Inflamatórios/farmacologia , Esteroides , DNA
4.
Toxicol Appl Pharmacol ; 438: 115911, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35143806

RESUMO

The therapeutic efficacy of tyrosine kinase inhibitors (TKIs) on solid tumors is limited by drug resistance and side effects. Currently, the combination therapy comprises of TKIs and angiogenesis inhibitors have been corroborated as an effective approach in cancer therapy. Ethoxy-erianin phosphate (EBTP) is an anti-angiogenic compound with low toxicity obtained by structural modification of the natural product erianin. Here, we aimed to evaluate whether EBTP can cooperate with TKIs to inhibit the proliferation and angiogenesis of tumor cells and reduce toxic effects. First, CCK-8 results showed that EBTP can effectively inhibit the proliferation of liver cancer cell line HepG2. We combined EBTP with four TKIs (Bosutinib, Apatinib, Afatinib and Erlotinib) to treat HepG2 cells and CompuSyn software analysis suggested that EBTP/Afatinib(Afa)shows the best synergistic inhibitory effect. Meanwhile, EBTP/Afa can significantly suppress the proliferation, invasion, migration and angiogenesis of HepG2 and HUVECs. ELISA results revealed that EBTP/Afa inhibits the secretion of VEGF in HepG2. EBTP/Afa down-regulates the expression of VEGF, p-VEGFR1, p-VEGFR2 and p-EGFR in both HepG2 and HUVECs. Further, the supernatant of HepG2 cells treated with EBTP/Afa blocks the intracellular downstream signal transduction shared by VEGF and EGFR in HUVECs. Finally, EBTP/Afa significantly inhibits tumor growth and angiogenesis in vivo. To conclude, EBTP/Afa targets VEGF and EGFR signaling pathways in liver cancer cells and tumor vasculature, thereby inhibiting the proliferation, motion and angiogenesis of liver cancer cells. Overall, this study provides a new combined strategy for the clinical treatment of hepatocellular carcinoma.


Assuntos
Afatinib/farmacologia , Bibenzilas/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Fenol/farmacologia , Fosfatos/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Células HCT116 , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neovascularização Patológica/metabolismo , Transdução de Sinais/efeitos dos fármacos
5.
J Biomed Sci ; 29(1): 95, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369000

RESUMO

BACKGROUND: Doublecortin-like kinase 1 (DCLK1) has been recognized as a marker of cancer stem cell in several malignancies. Thrombin is crucial in asthma severity as it can promote IL-8/CXCL8 production in lung epithelial cells, which is a potent chemoattractant for neutrophils. However, the pathologic role of DCLK1 in asthma and its involvement in thrombin-stimulated IL-8/CXCL8 expression remain unknown. METHODS: IL-8/CXCL8, thrombin, and DCLK1 expression were observed in the lung tissues of severe asthma patients and ovalbumin (OVA)-induced asthmatic mice model. A549 and BEAS-2B cells were either pretreated with inhibitors or small interfering RNAs (siRNAs) before being treated with thrombin. IL-8/CXCL8 expression and the molecules involved in signaling pathway were performed using ELISA, luciferase activity assay, Western blot, or ChIP assay. RESULTS: IL-8/CXCL8, thrombin, and DCLK1 were overexpressed in the lung tissues of severe asthma patients and ovalbumin (OVA)-induced asthmatic mice model. Our in vitro study found that DCLK siRNA or LRKK2-IN-1 (DCLK1 inhibitor) attenuated IL-8/CXCL8 release after thrombin induction in A549 and BEAS-2B cells. Thrombin activated DCLK1, RhoA, and YAP in a time-dependent manner, in which DCLK1 siRNA inhibited RhoA and YAP activation. YAP was dephosphorylated on the Ser127 site after thrombin stimulation, resulting in YAP translocation to the nucleus from the cytosol. DCLK1, RhoA and YAP activation following thrombin stimulation were inhibited by U0126 (ERK inhibitor). Moreover, DCLK1 and YAP siRNA inhibited κB-luciferase activity. Thrombin stimulated the recruitment of YAP and p65 to the NF-κB site of the IL-8/CXCL8 promoter and was inhibited by DCLK1 siRNA. CONCLUSIONS: Thrombin activates the DCLK1/RhoA signaling pathway, which promotes YAP activation and translocation to the nucleus from the cytosol, resulting in YAP/p65 formation, and binding to the NF-κB site, which enhances IL-8/CXCL8 expression. DCLK1 might be essential in thrombin-stimulated IL-8/CXCL8 expression in asthmatic lungs and indicates a potential therapeutic strategy for severe asthma treatment.


Assuntos
Asma , Interleucina-8 , Camundongos , Animais , Humanos , Interleucina-8/genética , Trombina/farmacologia , Trombina/metabolismo , NF-kappa B/metabolismo , RNA Interferente Pequeno/metabolismo , Ovalbumina/metabolismo , Quinases Semelhantes a Duplacortina , Fosforilação , Pulmão/metabolismo , Células Epiteliais/metabolismo , Asma/induzido quimicamente , Asma/genética , Luciferases/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Proteínas Serina-Treonina Quinases/genética
6.
Int J Mol Sci ; 23(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36362267

RESUMO

Genistein (GEN), a phytoestrogen, has been reported to regulate skeletal muscle endocrine factor expression and muscle fiber type switching, but its role in skeletal muscle regeneration is poorly understood. As a class of epigenetic regulators widely involved in skeletal muscle development, microRNAs (miRNAs) have the potential to treat skeletal muscle injury. In this study, we identified miR-221 and miR-222 and their target genes MyoG and Tnnc1 as key regulators during skeletal muscle regeneration, and both were regulated by GEN. C2C12 myoblasts and C2C12 myotubes were then used to simulate the proliferation and differentiation of muscle satellite cells during skeletal muscle regeneration. The results showed that GEN could inhibit the proliferation of satellite cells and promote the differentiation of satellite cells by inhibiting the expression of miR-221/222. Subsequent in vitro and in vivo experiments showed that GEN improved skeletal muscle regeneration mainly by promoting satellite cell differentiation in the middle and late stages, by regulating miR-221/222 expression. These results suggest that miR-221/222 and their natural regulator GEN have potential applications in skeletal muscle regeneration.


Assuntos
Genisteína , MicroRNAs , Genisteína/farmacologia , Desenvolvimento Muscular/genética , Mioblastos/metabolismo , Diferenciação Celular/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Músculo Esquelético/metabolismo , Proliferação de Células/genética
7.
J Cell Physiol ; 236(4): 3114-3128, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33078417

RESUMO

In cancer treatment, the most attractive feature of mesenchymal stem cells (MSCs) is it's homing to tumor tissues. MSC is an important part of the "colon cancer stem cell niche", but little research has been done on the tropism of human MSCs toward colon cancer stem cells (CCSCs). In this study, we first compared the effects of three tissue-derived MSCs (bone marrow, adipose tissue, and placenta) in vivo on colon tumor xenograft growth. Then, we analyzed the tropism of bone marrow-derived MSCs (BMSCs) toward normal intestinal epithelial cells (NCM460), parental colon cancer cells, CD133- /CD44-, and CD133+ /CD44+ colon cancer cells in vitro. Microarray analysis and in vitro experiments explored the mechanism of mediating the homing of BMSCs toward CCSCs. Compared with the parental and CD133- /CD44- colon cancer cells, CD133+ /CD44+ cells have a stronger ability to recruit BMSCs. In addition, BMSCs were significantly transformed into cancer-associated fibroblasts after being recruited by CCSCs. After coculture of BMSCs and CCSCs, the expression of interleukin (IL)-6, IL-8, IL-32, and CCL20 was significantly increased. Compared with parental strains, CD133- /CD44- cells, and NCM460, BMSC secreted significantly more IL-8 after coculture with CD133+ /CD44+ cells. Low concentration of IL-8 peptide inhibitors (100 ng/ml) and CXC receptor 2 (CXCR2) inhibitors have little effect on the migration of BMSCs, but can effectively weaken CCSC stemness and promote dormant CSCs in the coculture system to re-enter into the cell cycle. The endogenous IL-8 knockout in BMSCs or BMSCs loaded with IL-8 and/or CXCR2 inhibitors will make the therapy of BMSC targeting CCSCs function at its best.


Assuntos
Antígeno AC133/metabolismo , Neoplasias do Colo/patologia , Receptores de Hialuronatos/metabolismo , Interleucina-8/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Neoplásicas/patologia , Tropismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Autorrenovação Celular , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Células-Tronco Neoplásicas/metabolismo , Fenótipo , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Mol Med ; 27(1): 69, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34229599

RESUMO

BACKGROUND: Several studies have reported that hypoxia plays a pathological role in severe asthma and tissue fibrosis. Our previous study showed that hypoxia induces A disintegrin and metalloproteinase 17 (ADAM17) expression in human lung fibroblasts. Moreover, preadipocyte factor 1 (Pref-1) is cleaved by ADAM17, which participates in adipocyte differentiation. Furthermore, Pref-1 overexpression is involved in tissue fibrosis including liver and heart. Extracellular signal-regulated kinase (ERK) could active downstram gene expression through polyoma enhancer activator 3 (PEA3) phosphorylation. Studies have demonstrated that PEA3 and activator protein 1 (AP-1) play crucial roles in lung fibrosis, and the Pref-1 promoter region contains PEA3 and AP-1 binding sites as predicted. However, the roles of ERK, PEA3, and AP-1 in hypoxia-stimulated Pref-1 expression in human lung fibroblasts remain unknown. METHODS: The protein expression in ovalbumin (OVA)-induced asthmatic mice was performed by immunohistochemistry and immunofluorescence. The protein expression or the mRNA level in human lung fibroblasts (WI-38) was detected by western blot or quantitative PCR. Small interfering (si) RNA was used to knockdown gene expression. The collaboration with PEA3 and c-Jun were determined by coimmunoprecipitation. Translocation of PEA3 from the cytosol to the nucleus was observed by immunocytochemistry. The binding ability of PEA3 and AP-1 to Pref-1 promoter was assessed by chromatin immunoprecipitation. RESULTS: Pref-1 and hypoxia-inducible factor 1α (HIF-1α) were expressed in the lung sections of OVA-treated mice. Colocalization of PEA3 and Fibronectin was detected in lung sections from OVA-treated mice. Futhermore, Hypoxia induced Pref-1 protein upregulation and mRNA expression in human lung fibroblasts (WI-38 cells). In 60 confluent WI-38 cells, hypoxia up-regulated HIF-1α and Pref-1 protein expression. Moreover, PEA3 small interfering (si) RNA decreased the expression of hypoxia-induced Pref-1 in WI-38 cells. Hypoxia induced PEA3 phosphorylation, translocation of PEA3 from the cytosol to the nucleus, PEA3 recruitment and AP-1 binding to the Pref-1 promoter region, and PEA3-luciferase activity. Additionally, hypoxia induced c-Jun-PEA3 complex formation. U0126 (an ERK inhibitor), curcumin (an AP-1 inhibitor) or c-Jun siRNA downregulated hypoxia-induced Pref-1 expression. CONCLUSIONS: These results implied that ERK, PEA3, and AP-1 participate in hypoxia-induced Pref-1 expression in human lung fibroblasts.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Hipóxia/genética , Hipóxia/metabolismo , Pulmão/citologia , Pulmão/metabolismo , Proteínas de Membrana/genética , Transdução de Sinais , Animais , Biomarcadores , Proteínas de Ligação ao Cálcio/metabolismo , Linhagem Celular , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Modelos Biológicos , Fosforilação , Ligação Proteica , Proteínas Proto-Oncogênicas c-jun/metabolismo , Fatores de Transcrição/metabolismo
9.
Int J Mol Sci ; 21(23)2020 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-33260349

RESUMO

BACKGROUND: Lung epithelial cells play critical roles in idiopathic pulmonary fibrosis. METHODS: In the present study, we investigated whether transforming growth factor-ß (TGF-ß)-induced expression of connective tissue growth factor (CTGF) was regulated by the extracellular signal-regulated kinase (ERK)/a disintegrin and metalloproteinase 17 (ADAM17)/ribosomal S6 kinases 1 (RSK1)/CCAAT/enhancer-binding protein ß (C/EBPß) signaling pathway in human lung epithelial cells (A549). RESULTS: Our results revealed that TGF-ß-induced CTGF expression was weakened by ADAM17 small interfering RNA (ADAM17 siRNA), TNF-α processing inhibitor-0 (TAPI-0, an ADAM17 inhibitor), U0126 (an ERK inhibitor), RSK1 siRNA, and C/EBPß siRNA. TGF-ß-induced ERK phosphorylation as well as ADAM17 phosphorylation was attenuated by U0126. The TGF-ß-induced increase in RSK1 phosphorylation was inhibited by TAPI-0 and U0126. TGF-ß-induced C/EBPß phosphorylation was weakened by U0126, ADAM17 siRNA, and RSK1 siRNA. In addition, TGF-ß increased the recruitment of C/EBPß to the CTGF promoter. Furthermore, TGF-ß enhanced fibronectin (FN), an epithelial-mesenchymal transition (EMT) marker, and CTGF mRNA levels and reduced E-cadherin mRNA levels. Moreover, TGF-ß-stimulated FN protein expression was reduced by ADAM17 siRNA and CTGF siRNA. CONCLUSION: The results suggested that TGF-ß induces CTGF expression through the ERK/ADAM17/RSK1/C/EBPß signaling pathway. Moreover, ADAM17 and CTGF participate in TGF-ß-induced FN expression in human lung epithelial cells.


Assuntos
Proteína ADAM17/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Células Epiteliais/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Pulmão/citologia , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Células A549 , Células Epiteliais/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Fibronectinas/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Modelos Biológicos , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Intern Med J ; 49(10): 1299-1306, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30985051

RESUMO

BACKGROUND: Elevated D-dimer levels have been associated with poor outcomes in patients with cardiovascular disease. AIM: To study this association in elderly patients with chronic heart failure (CHF). METHODS: We analysed 1355 elderly patients who were admitted with CHF. All patients had D-dimer levels measured within the first 24 h following admission. A multivariate logistic regression model was used to assess the variables associated with chronic kidney disease. We used Cox regression analysis to assess the multivariable relationship between the D-dimer and subsequent all-cause death. RESULTS: In the multiple logistic regression analysis, the D-dimer was identified as a risk factor for chronic kidney disease (odds ratio = 1.278, 95% confidence interval 1.138 to 1.436, P < 0.001). The optimal cut-off level for D-dimer to predict all-cause death was found to be >885 ng/mL. In the multivariate Cox proportional-hazards model, a D-dimer level >885 ng/mL remained significantly associated with all-cause death (hazard ratio = 2.003, 95% confidence interval 1.334 to 3.010, P = 0.001). Additional analyses revealed that higher D-dimer levels were associated with an increased risk of all-cause death irrespective of the subtype of heart failure (including heart failure with reduced ejection fraction and heart failure with preserved ejection fraction). CONCLUSION: In elderly patients with CHF, measurement of D-dimer levels may help to risk stratify these patients, and high D-dimer levels might be regarded as a warning sign to intensify therapy.


Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/mortalidade , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , China/epidemiologia , Doença Crônica , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Insuficiência Renal Crônica/sangue , Fatores de Risco , Volume Sistólico , Análise de Sobrevida
12.
Neuroimage ; 174: 138-152, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29526742

RESUMO

A novel approach is presented for group statistical analysis of diffusion weighted MRI datasets through voxelwise Orientation Distribution Functions (ODF). Recent advances in MRI acquisition make it possible to use high quality diffusion weighted protocols (multi-shell, large number of gradient directions) for routine in vivo study of white matter architecture. The dimensionality of these data sets is however often reduced to simplify statistical analysis. While these approaches may detect large group differences, they do not fully capitalize on all acquired image volumes. Incorporation of all available diffusion information in the analysis however risks biasing the outcome by outliers. Here we propose a statistical analysis method operating on the ODF, either the diffusion ODF or fiber ODF. To avoid outlier bias and reliably detect voxelwise group differences and correlations with demographic or behavioral variables, we apply the Low-Rank plus Sparse (L+S) matrix decomposition on the voxelwise ODFs which separates the sparse individual variability in the sparse matrix S whilst recovering the essential ODF features in the low-rank matrix L. We demonstrate the performance of this ODF L+S approach by replicating the established negative association between global white matter integrity and physical obesity in the Human Connectome dataset. The volume of positive findings p<0.01,227cm3, agrees with and expands on the volume found by TBSS (17 cm3), Connectivity based fixel enhancement (15 cm3) and Connectometry (212 cm3). In the same dataset we further localize the correlations of brain structure with neurocognitive measures such as fluid intelligence and episodic memory. The presented ODF L+S approach will aid in the full utilization of all acquired diffusion weightings leading to the detection of smaller group differences in clinically relevant settings as well as in neuroscience applications.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/anatomia & histologia , Imagem de Difusão por Ressonância Magnética , Processamento de Imagem Assistida por Computador/métodos , Substância Branca/anatomia & histologia , Adulto , Algoritmos , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
13.
Eur J Nucl Med Mol Imaging ; 45(9): 1596-1604, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29704038

RESUMO

PURPOSE: Off-target binding in the reference region is a challenge for recent tau tracers 18F-AV-1451 and 18F-THK5351. The conventional standardized uptake value ratio (SUVR) method relies on the average uptake from an unaffected tissue sample, and therefore is susceptible to biases from off-target binding as well as variability among individuals in the reference region. We propose a new method, standardized uptake value peak-alignment (SUVP), to reduce the bias of the SUVR, and improve the quantitative assessment of tau deposition. METHODS: The SUVP normalizes uptake values by their mode and standard deviation. Instead of using a reference region, the SUVP derives the contrast from unaffected voxels over the whole brain. Using SUVP and SUVR methods, we evaluated the global and regional tau binding of 18F-THK5351 and 18F-AV-1451 on two independent cohorts (N = 18 and 32, respectively), each with cognitively normal (NL) subjects and Alzheimer's disease (AD) subjects. RESULTS: Both tracers showed significantly increased binding for AD in the targeted cortical areas. In the temporal cortex, SUVP had a higher classification success rate (CSR) than SUVR (0.96 vs 0.89 for 18F-THK5351; 0.86 vs 0.75 for 18F-AV-1451), as well as higher specificity under fixed sensitivity around 0.80 (0.70 vs 0.45 specificity for 18F-THK5351; 1.00 vs 0.78 for 18F-AV-1451). In the cerebellar cortex, an AD-NL group difference with effect size (Cohen's d) of 0.62 was observed for AV-1451, confirming the limitation of the SUVR approach using this region as a reference. A smaller cerebellar effect size (0.09) was observed for THK5351. CONCLUSION: The SUVP method reduces the bias of the reference region and improves the NL-AD classification compared to the SUVR approach.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Aminopiridinas/farmacocinética , Carbolinas/farmacocinética , Tomografia por Emissão de Pósitrons , Quinolinas/farmacocinética , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Nephrology (Carlton) ; 22(2): 101-106, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27786399

RESUMO

As one of the manifestations of patients with systemic lupus erythematosus, lupus nephritis (LN) has high morbidity and mortality. Although the explicit mechanism of LN remains to be fully elucidated, there is increasing evidence to support the notion that tumour necrosis factor-related weak inducer of apoptosis (TWEAK), acting via its sole receptor, fibroblast growth factor-inducible 14 (Fn14), plays a pivotal role in such pathologic process. TWEAK/Fn14 interactions occur prominently in kidneys of LN, inducing inflammatory responses, angiogenesis, mesangial proliferation, filtration barrier injuries, renal fibrosis, etc. This review will specify the important roles of TWEAK/Fn14 pathway in the pathogenesis of LN with experimental data from cellular and animal models. Additionally, the raised levels of urinary and serum soluble TWEAK correlate with renal disease activity in patients with LN. The neutralizing antibodies targeting TWEAK or other approaches inhibiting TWEAK/Fn14 signals can attenuate renal damage in the murine lupus models. Therefore, to focus on TWEAK/Fn14 signalling may be promising in both clinical evaluation and the treatment of patients with LN.


Assuntos
Rim/metabolismo , Nefrite Lúpica/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Transdução de Sinais , Fatores de Necrose Tumoral/metabolismo , Animais , Proliferação de Células , Citocina TWEAK , Modelos Animais de Doenças , Fibrose , Humanos , Mediadores da Inflamação/metabolismo , Rim/efeitos dos fármacos , Rim/patologia , Rim/fisiopatologia , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/patologia , Nefrite Lúpica/fisiopatologia , Terapia de Alvo Molecular , Receptores do Fator de Necrose Tumoral/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Receptor de TWEAK , Inibidores do Fator de Necrose Tumoral
15.
Nat Commun ; 15(1): 705, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267418

RESUMO

Toxic amyloid-beta (Aß) plaque and harmful inflammation are two leading symptoms of Alzheimer's disease (AD). However, precise AD therapy is unrealizable due to the lack of dual-targeting therapy function, poor BBB penetration, and low imaging sensitivity. Here, we design a near-infrared-II aggregation-induced emission (AIE) nanotheranostic for precise AD therapy. The anti-quenching emission at 1350 nm accurately monitors the in vivo BBB penetration and specifically binding of nanotheranostic with plaques. Triggered by reactive oxygen species (ROS), two encapsulated therapeutic-type AIE molecules are controllably released to activate a self-enhanced therapy program. One specifically inhibits the Aß fibrils formation, degrades Aß fibrils, and prevents the reaggregation via multi-competitive interactions that are verified by computational analysis, which further alleviates the inflammation. Another effectively scavenges ROS and inflammation to remodel the cerebral redox balance and enhances the therapy effect, together reversing the neurotoxicity and achieving effective behavioral and cognitive improvements in the female AD mice model.


Assuntos
Doença de Alzheimer , Feminino , Animais , Camundongos , Doença de Alzheimer/terapia , Espécies Reativas de Oxigênio , Peptídeos beta-Amiloides , Citoesqueleto , Inflamação , Placa Amiloide
16.
RSC Adv ; 13(6): 3766-3772, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36756605

RESUMO

We prepared polymer-based encapsulation films by plasma-enhanced atomic layer deposition (PEALD) of Al2O3 film on a polycarbonate (PC) substrate at 80-160 °C to fabricate Al2O3/PC barrier films. The thermal and dynamic mechanical properties of the PC substrate, the structural evolution of PEALD Al2O3 films, the optical transmission, surface morphology, and gas-barrier properties of Al2O3/PC film are all studied in this work as a function of temperature. The glass transition temperature T g of the PC substrate is about 140 °C, and the coefficient of thermal expansion increases significantly when the temperature exceeds T g. Increasing the deposition temperature from 80 to 160 °C for Al2O3 film deposited over 300 cycles increases the density from 3.24 to 3.45 g cm-3, decreases the thickness from 44 to 40 nm, and decreases the O/Al content ratio from 1.525 to 1.406. Al2O3/PC films deposited at 80-120 °C have no surface cracks, whereas surface cracks appear in samples deposited near or above 140 °C. Upon increasing the deposition temperature, the water vapor transmission rate (WVTR) and oxygen transmission rate (OTR) of Al2O3/PC films decrease significantly at temperatures below T g, and then increase at temperatures near to or above T g due to cracks in the films. The optimal deposition temperature is 120 °C, and the minimum WVTR and OTR of Al2O3/PC film are 0.00132 g per (m2 24 h) and 0.11 cm3 per (m2 24 h 0.1 MPa), respectively. The gas-barrier properties of the Al2O3/PC films are attributed to both the densification of the Al2O3 film and the cracks, which are caused by the shrinkage of the PC substrate.

17.
Front Immunol ; 14: 1293425, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38111582

RESUMO

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy and low-flow perimedullary arteriovenous fistulas (PMAVFs) may cause longitudinal widespread myelopathy. We report a middle-aged male patient with autoimmune GFAP astrocytopathy complicated with low flow PMAVFs disease, presenting with lower extremity weakness and dysuria. Magnetic resonance imaging (MRI) of the spinal cord revealed a significant longitudinal extent of T2 high signal from T11 to L1, with the lesion located proximal to the vascular territory supplied by the anterior spinal artery. Multiple patchy abnormal signals were seen adjacent to the anterior and posterior horns of the lateral ventricles bilaterally and at the centers of the semi-ovals on MRI of the cranial brain, with iso signal in T1Flair, the high signal in T2WI, and no high signal seen in Diffusion Weighted Imaging (DWI). Subsequently, the presence of anti-GFAP antibodies was detected in the cerebrospinal fluid (CSF), and the diagnosis of autoimmune GFAP astrocytopathy in conjunction with low-flow PMAVFs was confirmed through spinal digital subtraction angiography (DSA). This case report aims to increase neurologists' awareness of this disease and avoid missed or misdiagnosed cases that may lead to delayed treatment.


Assuntos
Fístula Arteriovenosa , Doenças da Medula Espinal , Humanos , Masculino , Pessoa de Meia-Idade , Fístula Arteriovenosa/diagnóstico por imagem , Fístula Arteriovenosa/complicações , Encéfalo , Proteína Glial Fibrilar Ácida , Doenças da Medula Espinal/etiologia
18.
Materials (Basel) ; 16(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36837227

RESUMO

The rheological properties of warm-mix recycled asphalt binders are critical to enhancing design quality and interpreting the performance mechanisms of the corresponding mixtures. This study investigated the rheological behavior of warm-mix recycled asphalt binders with high percentages of RAP binder. The effects of two warm-mix additives [wax-based Sasobit (S) and surfactant-based Evotherm-M1 (E)], a rejuvenating aging [ZGSB (Z)], four RAP binder contents (0%, 30%, 50% and 70%), and three aging states (unaged, short-term aged and long-term aged) were evaluated in detail using the dynamic shear rheometer (DSR), bending beam rheometer (BBR) and Brookfield rotational viscometer tests as well as conventional performance tests over the whole range of temperatures. The results showed that the rejuvenating agent Z effectively alleviated the aging effect of the RAP binder; however, it could hardly eliminate entirely this negative impact, especially at higher RAP binder contents. The addition of S remarkably lowered the apparent viscosity of the warm-mix recycled binders by up to 35.0%, whereas E had little influence on the binder viscosity due to its surfactant nature. Besides, S performed much better in improving rutting resistance (with the increase of up to 411.3% in |G*|/sinδ) than E, while E exhibited superior fatigue performance (with the reduction of up to 42.3% in |G*|·sinδ) to that of S. In terms of the thermal cracking resistance, E had very slight influence and S even yielded an adverse impact (with the increase of up to 70.2% in Sa and the decrease of up to 34.1% in m-value). Further, S broadened the ranges of pavement service temperatures by about 12 °C, whereas E almost did not change the PG grades of the binders. Finally, regarding the characteristics of viscoelastic master curves, S considerably improved the dynamic modulus and lowered the phase angle of the binders over a wide range of frequencies and temperatures but led to the failure of the time-temperature superposition principle due to its thermorheologically complex nature. Nevertheless, in this regard, the effect of E was found very mild.

19.
Front Plant Sci ; 14: 1144326, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37056511

RESUMO

Natural antioxidants are more attractive than synthetic chemical oxidants because of their non-toxic and non-harmful properties. Microalgal bioactive components such as carotenoids, polysaccharides, and phenolic compounds are gaining popularity as very effective and long-lasting natural antioxidants. Few articles currently exist that analyze microalgae from a bibliometric and visualization point of view. This study used a bibliometric method based on the Web of Science Core Collection database to analyze antioxidant research on bioactive compounds in microalgae from 1996 to 2022. According to cluster analysis, the most studied areas are the effectiveness, the antioxidant mechanism, and use of bioactive substances in microalgae, such as carotene, astaxanthin, and tocopherols, in the fields of food, cosmetics, and medicine. Using keyword co-occurrence and keyword mutation analysis, future trends are predicted to improve extraction rates and stability by altering the environment of microalgae cultures or mixing extracts with chemicals such as nanoparticles for commercial and industrial applications. These findings can help researchers identify trends and resources to build impactful investigations and expand scientific frontiers.

20.
Schizophr Res ; 261: 100-106, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37716202

RESUMO

BACKGROUND: The striatal-pallidal pathway plays an important role in cognitive control and modulation of behaviors. Globus pallidus interna (GPi), as a primary output structure, is crucial in modulating excitation and inhibition. Studies of GPi in psychiatric illnesses are lacking given the technical challenges of examining this small and functionally diverse subcortical structure. METHODS: 71 medication-naïve first episode schizophrenia (FES) participants and 73 healthy controls (HC) were recruited at the Shanghai Mental Health Center. Clinical symptoms and imaging data were collected at baseline and, in a subset of patients, 8 weeks after initiating treatment. Resting-state functional connectivity of sub-regions of the GP were assessed using a novel mask that combines two atlases to create 8 ROIs in the GP. RESULTS: Baseline imaging data from 63 FES patients and 55 HC met quality standards and were analyzed. FES patients exhibited less negative connectivity and increased positive connectivity between the right anterior GPi and several cortical and subcortical areas at baseline compared to HC (PFWE < 0.05). Positive functional connectivity between the right anterior GPi and several brain areas, including the right dorsal anterior cingulate gyrus, was associated with severity of positive symptoms (PFWE < 0.05) and predicted treatment response after 8 weeks (n = 28, adjusted R2 = 0.486, p < 0.001). CONCLUSIONS: Our results implicate striatal-pallidal-thalamic pathways in antipsychotic efficacy. If replicated, these findings may reflect failure of neurodevelopmental processes in adolescence and early adulthood that decrease functional connectivity as an index of failure of the limbic/associative GPi to appropriately inhibit irrelevant signals in psychosis.


Assuntos
Esquizofrenia , Adolescente , Humanos , Adulto , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/tratamento farmacológico , Globo Pálido/diagnóstico por imagem , Mapeamento Encefálico , Imageamento por Ressonância Magnética/métodos , China
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