Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 84
Filtrar
1.
BMC Geriatr ; 24(1): 28, 2024 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184539

RESUMO

BACKGROUND: The current literature shows a strong relationship between retinal neuronal and vascular alterations in dementia. The purpose of the study was to use NFN+ deep learning models to analyze retinal vessel characteristics for cognitive impairment (CI) recognition. METHODS: We included 908 participants from a community-based cohort followed for over 15 years (the prospective KaiLuan Study) who underwent brain magnetic resonance imaging (MRI) and fundus photography between 2021 and 2022. The cohort consisted of both cognitively healthy individuals (N = 417) and those with cognitive impairment (N = 491). We employed the NFN+ deep learning framework for retinal vessel segmentation and measurement. Associations between Retinal microvascular parameters (RMPs: central retinal arteriolar / venular equivalents, arteriole to venular ratio, fractal dimension) and CI were assessed by Pearson correlation. P < 0.05 was considered statistically significant. The correlation between the CI and RMPs were explored, then the correlation coefficients between CI and RMPs were analyzed. Random Forest nonlinear classification model was used to predict whether one having cognitive decline or not. The assessment criterion was the AUC value derived from the working characteristic curve. RESULTS: The fractal dimension (FD) and global vein width were significantly correlated with the CI (P < 0.05). Age (0.193), BMI (0.154), global vein width (0.106), retinal vessel FD (0.099), and CRAE (0.098) were the variables in this model that were ranked in order of feature importance. The AUC values of the model were 0.799. CONCLUSIONS: Establishment of a predictive model based on the extraction of vascular features from fundus images has a high recognizability and predictive power for cognitive function and can be used as a screening method for CI.


Assuntos
Disfunção Cognitiva , Aprendizado Profundo , Humanos , Estudos Prospectivos , Disfunção Cognitiva/diagnóstico por imagem , Retina , Vasos Retinianos/diagnóstico por imagem , Biomarcadores
2.
Alzheimers Dement ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38872387

RESUMO

INTRODUCTION: We delineated the associations among long-term blood pressure variability (BPV), brain structure, and cognitive function. METHODS: We included 1254 adult participants from the Kailuan study. BPV was calculated from 2006 to 2020. Brain magnetic resonance imaging (MRI) and Montreal Cognitive Assessment (MoCA) were conducted in 2020. RESULTS: Higher systolic BPV (SBPV) and diastolic BPV (DBPV) were associated with lower total and frontal gray matter (GM) volume, and higher SBPV was associated with lower temporal GM volume. Elevated DBPV was associated with lower volume of total brain and parietal GM, and higher white matter hyperintensity (WMH) volume. Higher SBPV and DBPV were associated with lower MoCA scores. Decreased total and regional GM volume and increased WMH volume were associated with lower MoCA scores. The association between SBPV and cognitive function was mediated by total, frontal, and temporal GM volume. DISCUSSION: GM volume may play key roles in the association between SBPV and cognitive function. HIGHLIGHTS: SBPV and DBPV were negatively associated with total and regional brain volume. SBPV and DBPV were negatively associated with cognitive function. Decreased brain volume was associated with cognitive decline. GM volume mediated the negative association between SBPV and cognitive function.

3.
Environ Sci Technol ; 57(35): 13236-13246, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37615390

RESUMO

Development of cost-effective oxide catalysts holds the key to the removal of toluene, one of the most important volatile organic compounds. However, the catalysts follow varied working mechanisms at different reaction temperatures, posing a challenge to achieving efficient toluene removal over a wide temperature range. Here we report an agitation-assisted molten salt method, which achieves the rational doping on a two-dimensional Co3O4 catalyst and forms two different structures of active sites to enhance catalytic oxidation of toluene in specific temperature intervals, enabling a facile tandem design for working in a wide temperature range. Specifically, Co3O4 is doped with Cu at the octahedral site (Cu-Co3O4) and Zn at the tetrahedral site (Zn-Co3O4) to form CuOh-O-CoTe and ZnTe-O-CoOh structures on the surface, respectively. Mechanistic studies reveal the different working mechanisms of these two active sites toward remarkable performance enhancement at specific temperature intervals, and the improved performance derived from accelerated consumption of intermediates adsorbed on the catalyst surface. Taken together, Cu-Co3O4 and Zn-Co3O4 achieve excellent toluene purification performance over a wide temperature range. This work provides insights into the mechanism-oriented design of active sites at the atomic level.


Assuntos
Cobalto , Tolueno , Temperatura , Catálise
4.
Cancer Sci ; 113(1): 319-333, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34714590

RESUMO

Dysregulation of long noncoding RNA SNHG17 is associated with the occurrence of several tumors; however, its role in esophageal squamous cell carcinoma (ESCC) remains obscure. The present study demonstrated that SNHG17 was upregulated in ESCC tissues and cell lines, induced by TGF-ß1, and associated with poor survival. It is also involved in the epithelial-to-mesenchymal transition (EMT) process. The mechanism underlying SNHG17-regulated c-Myc was detected by RNA immunoprecipitation, RNA pull-down, chromatin immunoprecipitation, and luciferase reporter assays. SNHG17 was found to directly regulate c-Myc transcription by binding to c-Jun protein and recruiting the complex to specific sequences of the c-Myc promoter region, thereby increasing its expression. Moreover, SNHG17 hyperactivation induced by TGF-ß1 results in PI3K/AKT pathway activation, promoting cells EMT, forming a positive feedback loop. Furthermore, SNHG17 facilitated ESCC tumor growth in vivo. Overall, this study demonstrated that the SNHG17/c-Jun/c-Myc axis aggravates ESCC progression and EMT induction by TGF-ß1 and may serve as a new therapeutic target for ESCC.


Assuntos
Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-myc/genética , RNA Longo não Codificante/genética , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Estadiamento de Neoplasias , Transplante de Neoplasias , Regulação para Cima
5.
Appl Environ Microbiol ; 88(13): e0063222, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35708325

RESUMO

Exogenic deposits are an important source of rare earth elements (REEs), especially heavy REEs (HREEs). It is generally accepted that microorganisms are able to dissolve minerals and mobilize elements in supergene environments. However, little is known about the roles of microorganisms in the formation of exogenic deposits such as regolith-hosted REE deposits that are of HREE enrichment and provide over 90% of global HREE demand. In this study, we characterized the microbial community composition and diversity along a complete weathering profile drilled from a regolith-hosted REE deposit in Southeastern China and report the striking contributions of microorganisms to the enrichment of REEs and fractionation between HREEs and light REEs (LREEs). Our results provide evidence that the variations in REE contents are correlated with microbial community along the profile. Both fungi and bacteria contributed to the accumulation of REEs, whereas bacteria played a key role in the fractionation between HREEs and LREEs. Taking advantage of bacteria strains isolated from the profile, Gram-positive bacteria affiliated with Bacillus and Micrococcus preferentially adsorbed HREEs, and teichoic acids in the cell wall served as the main sites for HREE adsorption, leading to an enrichment of HREEs in the deposit. The present study provides the first database of microbial community in regolith-hosted REE deposits. These findings not only elucidate the crucial contribution of fungi and bacteria in the supergene REE mineralization but also provide insights into efficient utilization of mineral resources via a biological pathway. IMPORTANCE Understanding the role of microorganisms in the formation of regolith-hosted rare earth element (REE) deposits is beneficial for improving the metallogenic theory and deposit exploitation, given that such deposits absolutely exist in subtropical regions with strong microbial activities. Little is known of the microbial community composition and its contribution to REE mineralization in this kind of deposit. Using a combination of high-throughput sequencing, batch adsorption experiments, and spectroscopic characterization, the functional microorganisms contributing to REE enrichment and fractionation are disclosed. For bacteria, the surface carboxyl and phosphate groups are active sites for REE adsorption, while teichoic acids in the cell walls of G+ bacteria lead to REE fractionation. The above-mentioned findings not only unravel the importance of microorganisms in the formation of supergene REE deposits but also provide experimental evidence for the bioutilization of REE resources.


Assuntos
Metais Terras Raras , Ácidos Teicoicos , Adsorção , Fracionamento Químico , Metais Terras Raras/metabolismo , Fosfatos
6.
Am J Respir Crit Care Med ; 204(3): 312-325, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33784491

RESUMO

Rationale: CD148/PTRJ (receptor-like protein tyrosine phosphatase η) exerts antifibrotic effects in experimental pulmonary fibrosis via interactions with its ligand syndecan-2; however, the role of CD148 in human pulmonary fibrosis remains incompletely characterized.Objectives: We investigated the role of CD148 in the profibrotic phenotype of fibroblasts in idiopathic pulmonary fibrosis (IPF).Methods: Conditional CD148 fibroblast-specific knockout mice were generated and exposed to bleomycin and then assessed for pulmonary fibrosis. Lung fibroblasts (mouse lung and human IPF lung), and precision-cut lung slices from human patients with IPF were isolated and subjected to experimental treatments. A CD148-activating 18-aa mimetic peptide (SDC2-pep) derived from syndecan-2 was evaluated for its therapeutic potential.Measurements and Main Results: CD148 expression was downregulated in IPF lungs and fibroblasts. In human IPF lung fibroblasts, silencing of CD148 increased extracellular matrix production and resistance to apoptosis, whereas overexpression of CD148 reversed the profibrotic phenotype. CD148 fibroblast-specific knockout mice displayed increased pulmonary fibrosis after bleomycin challenge compared with control mice. CD148-deficient fibroblasts exhibited hyperactivated PI3K/Akt/mTOR signaling, reduced autophagy, and increased p62 accumulation, which induced NF-κB activation and profibrotic gene expression. SDC2-pep reduced pulmonary fibrosis in vivo and inhibited IPF-derived fibroblast activation. In precision-cut lung slices from patients with IPF and control patients, SDC2-pep attenuated profibrotic gene expression in IPF and normal lungs stimulated with profibrotic stimuli.Conclusions: Lung fibroblast CD148 activation reduces p62 accumulation, which exerts antifibrotic effects by inhibiting NF-κB-mediated profibrotic gene expression. Targeting the CD148 phosphatase with activating ligands such as SDC2-pep may represent a potential therapeutic strategy in IPF.


Assuntos
Fibroblastos/metabolismo , Fibrose Pulmonar Idiopática/genética , Pulmão/metabolismo , Animais , Antibióticos Antineoplásicos/toxicidade , Autofagia/efeitos dos fármacos , Autofagia/genética , Bleomicina/toxicidade , Modelos Animais de Doenças , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Técnicas In Vitro , Pulmão/efeitos dos fármacos , Pulmão/patologia , Camundongos , Camundongos Knockout , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Fragmentos de Peptídeos/farmacologia , Fenótipo , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/genética , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/metabolismo , Transdução de Sinais , Sindecana-2/farmacologia , Serina-Treonina Quinases TOR/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
7.
J Environ Sci (China) ; 101: 293-303, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33334524

RESUMO

Ceria is widely used as a catalyst for soot combustion, but effects of Zr substitution on the reaction mechanism is ambiguous. The present work elucidates effects of Zr substitution on soot combustion over cubic fluorite-structured nanoceria. The nanostructured CeO2, Ce0.92Zr0.08O2, and Ce0.84Zr0.16O2 composed of 5-6 nm crystallites display Tm-CO2 (the temperature at maximum CO2 yield) at 383, 355, and 375°C under 10 vol.% O2/N2, respectively. The size of agglomerate decreases from 165.5 to 51.9-57.3 nm, which is beneficial for the soot-ceria contact. Moreover, Zr increases the amount of surface oxygen vacancies, generating more active oxygen (O2- and O-) for soot oxidation. Thus, the activities of Ce0.92Zr0.08O2 and Ce0.84Zr0.16O2 in soot combustion are better than that of CeO2. Although oxygen vacancies promote the migration of lattice O2-, the enriched surface Zr also inhibits the mobility of lattice O2-. Therefore, the Tm-CO2 of Ce0.84Zr0.16O2 is higher than that of Ce0.92Zr0.08O2. Based on reaction kinetic study, soot in direct contact with ceria preferentially decomposes with low activation energy, while the oxidation of isolated soot occurs through diffusion with high activation energy. The obtained findings provide new understanding on the soot combustion over nanoceria.


Assuntos
Cério , Fuligem , Catálise , Oxigênio
8.
J Cell Mol Med ; 24(16): 8962-8976, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32583631

RESUMO

Long non-coding RNAs (lncRNAs) have been well demonstrated to emerge as crucial regulators in cancer progression, and they can function as regulatory network based on their interactions. Although the biological functions of FAM83H-AS1 have been confirmed in various tumour progressions, the underlying molecular mechanisms of FAM83H-AS1 in oesophageal squamous cell carcinoma (ESCC) remained poorly understood. To address this, we treated human oesophageal cancer cell line Eca109 cells with TGF-ß and found FAM83H-AS1 was notably overexpressed. In the present study, FAM83H-AS1 was observed to be significantly up-regulated in ESCC tissues and was associated with TNM stage, pathological differentiation and lymph node metastasis. FAM83H-AS1 reinforced oesophageal cancer cell proliferation, migration and invasion, and participated in epithelial-to-mesenchymal transition (EMT) process at mRNA and protein levels. In addition, a concordant regulation between FAM83H-AS1 and its sense strand FAM83H was detected at the transcriptional and translational levels. Furthermore, FAM83H-AS1 could act as competing endogenous RNA to affect the expression of Girdin by sponging miR-10a-5p verified by RIP and luciferase reporter assays. Consequently, the study provided a unique perspective of FAM83H-AS1 in ESCC progression, which may be considered as potential biomarker and therapeutic target for ESCC therapy.


Assuntos
Carcinoma de Células Escamosas do Esôfago/genética , MicroRNAs/genética , Proteínas dos Microfilamentos/genética , Proteínas/genética , Proteínas de Transporte Vesicular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Metástase Linfática/genética , Metástase Linfática/patologia , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , RNA Mensageiro/genética , Regulação para Cima/genética
9.
Arch Biochem Biophys ; 686: 108371, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32325088

RESUMO

Understanding the role of Long non-coding RNAs (lncRNAs) in tumorigenesis in diverse human malignancies would helpful for targeted therapies, containing esophageal squamous cell carcinoma (ESCC). However, the specific role and molecular mechanisms of LINC01980 in ESCC remain unclarified. In this study, we investigated the expression level, function role, and molecular mechanisms of LINC01980 in esophageal cancer cells and ESCC tissues. The high expression of LINC01980 was detected in ESCC tissues and cells, and predicted poor prognosis. LINC01980 promoted the cell proliferation, migration, invasion ability and epithelial-mesenchymal transition (EMT) progress in ESCC cells. In addition, a negative correlation between LINC01980 and miR-190a-5p or miR-190a-5p and MYO5A was observed in ESCC. We found that miR-190a-5p could directly bind with the mRNA of LINC01980 and MYO5A, and it was detected low expression in ESCC. We further demonstrated that the downregulation of MYO5A caused by overexpressing miR-190a-5p was released via upregulation of LINC01980. Functionally, LINC01980 acted as a competitively endogenous RNA (ceRNA) to impact the expression of MYO5A by sponging miR-190a-5p in ESCC. Therefore, these findings suggest that LINC01980 may act as an oncogenic lncRNA in ESCC and LINC01980/miR-190a-5p/MYO5A pathway contributes to the development of ESCC.


Assuntos
Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , MicroRNAs/metabolismo , Cadeias Pesadas de Miosina/genética , Miosina Tipo V/genética , RNA Longo não Codificante/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Regulação para Baixo , Transição Epitelial-Mesenquimal , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos
10.
FASEB J ; 33(3): 3562-3574, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30462529

RESUMO

Fatty acid binding protein 4 (FABP4), an intracellular lipid chaperone and adipokine, is expressed by lung macrophages, but the function of macrophage-FABP4 remains elusive. We investigated the role of FABP4 in host defense in a murine model of Pseudomonas aeruginosa pneumonia. Compared with wild-type (WT) mice, FABP4-deficient (FABP4-/-) mice exhibited decreased bacterial clearance and increased mortality when challenged intranasally with P. aeruginosa. These findings in FABP4-/- mice were associated with a delayed neutrophil recruitment into the lungs and were followed by greater acute lung injury and inflammation. Among leukocytes, only macrophages expressed FABP4 in WT mice with P. aeruginosa pneumonia. Chimeric FABP4-/- mice with WT bone marrow were protected from increased mortality seen in chimeric WT mice with FABP4-/- bone marrow during P. aeruginosa pneumonia, thus confirming the role of macrophages as the main source of protective FABP4 against that infection. There was less production of C-X-C motif chemokine ligand 1 (CXCL1) in FABP4-/- alveolar macrophages and lower airway CXCL1 levels in FABP4-/- mice. Delivering recombinant CXCL1 to the airways protected FABP4-/- mice from increased susceptibility to P. aeruginosa pneumonia. Thus, macrophage-FABP4 has a novel role in pulmonary host defense against P. aeruginosa infection by facilitating crosstalk between macrophages and neutrophils via regulation of macrophage CXCL1 production.-Liang, X., Gupta, K., Rojas Quintero, J., Cernadas, M., Kobzik, L., Christou, H., Pier, G. B., Owen, C. A., Çataltepe, S. Macrophage FABP4 is required for neutrophil recruitment and bacterial clearance in Pseudomonas aeruginosa pneumonia.


Assuntos
Proteínas de Ligação a Ácido Graxo/imunologia , Macrófagos Alveolares/imunologia , Neutrófilos/imunologia , Pneumonia/imunologia , Pseudomonas aeruginosa/imunologia , Lesão Pulmonar Aguda/imunologia , Animais , Medula Óssea/imunologia , Quimiocina CXCL1/imunologia , Inflamação/imunologia , Pulmão/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Infiltração de Neutrófilos/imunologia , Infecções por Pseudomonas/imunologia
11.
Am J Respir Cell Mol Biol ; 61(6): 737-746, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31461627

RESUMO

The impact of lipotoxicity on the development of lung fibrosis is unclear. Saturated fatty acids, such as palmitic acid (PA), activate endoplasmic reticulum (ER) stress, a cellular stress response associated with the development of idiopathic pulmonary fibrosis (IPF). We tested the hypothesis that PA increases susceptibility to lung epithelial cell death and experimental fibrosis by modulating ER stress. Total liquid chromatography and mass spectrometry were used to measure fatty acid content in IPF lungs. Wild-type mice were fed a high-fat diet (HFD) rich in PA or a standard diet and subjected to bleomycin-induced lung injury. Lung fibrosis was determined by hydroxyproline content. Mouse lung epithelial cells were treated with PA. ER stress and cell death were assessed by Western blotting, TUNEL staining, and cell viability assays. IPF lungs had a higher level of PA compared with controls. Bleomycin-exposed mice fed an HFD had significantly increased pulmonary fibrosis associated with increased cell death and ER stress compared with those fed a standard diet. PA increased apoptosis and activation of the unfolded protein response in lung epithelial cells. This was attenuated by genetic deletion and chemical inhibition of CD36, a fatty acid transporter. In conclusion, consumption of an HFD rich in saturated fat increases susceptibility to lung fibrosis and ER stress, and PA mediates lung epithelial cell death and ER stress via CD36. These findings demonstrate that lipotoxicity may have a significant impact on the development of lung injury and fibrosis by enhancing pro-death ER stress pathways.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ácido Palmítico/toxicidade , Fibrose Pulmonar/induzido quimicamente , Animais , Apoptose/efeitos dos fármacos , Antígenos CD36/deficiência , Antígenos CD36/fisiologia , Células Epiteliais/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ácido Palmítico/administração & dosagem , Ácido Palmítico/farmacocinética , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia
12.
Gastric Cancer ; 22(4): 705-722, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30656427

RESUMO

BACKGROUND: Semaphorin 3B (SEMA3B) is frequently inactivated in several carcinomas. However, as the host gene of miR-6872, the roles of SEMA3B, antisense lncRNA SEMA3B-AS1, and miR-6872 in gastric cardia adenocarcinoma (GCA) tumorigenesis have not been clarified. METHODS: The expression levels of SEMA3B, SEMA3B-AS1, and miR-6872 were respectively detected by qRT-PCR, western blot, or immunohistochemical staining assays. The methylation status was determined by BGS and BS-MSP methods. In vitro assays were preformed to explore the biological effects of SEMA3B, SEMA3B-AS1, and miR-6872-5p in gastric cancer cells. Chromatin immunoprecipitation assay was used to detect the binding of protein to DNA. The interaction of SEMA3B-AS1 with MLL4 was identified by RNA immunoprecipitation and RNA pull-down assays. RESULTS: Frequent downregulation of SEMA3B, SEMA3B-AS1, and miR-6872 was detected in GCA tissues and gastric cancer cells. Aberrant hypermethylation of the promoter region was more tumor specific and was negatively correlated with the expression level of SEMA3B, SEMA3B-AS1, and miR-6872-5p. Transcription factor Sp1 activated SEMA3B or SEMA3B-AS1 transcription and CpG sites hypermethylation within promoter region eliminated Sp1 binding ability. Overexpression of SEMA3B and SEMA3B-AS1 inhibited gastric cancer cell proliferation, migration, and invasion in vitro. SEMA3B-AS1 induced the expression of SEMA3B by interacting with MLL4. ZNF143 might be the target gene of miR-6872-5p and miR-6872-5p functioning synergistically with SEMA3B to suppress cell invasion. Furthermore, SEMA3B, SEMA3B-AS1, and miR-6872-5p expression levels were associated with GCA patients' survival. CONCLUSIONS: SEMA3B, SEMA3B-AS1, and miR-6872 may act as tumor suppressors and may serve as potential targets for antitumor therapy.


Assuntos
Adenocarcinoma/patologia , Cárdia/patologia , Glicoproteínas de Membrana/genética , MicroRNAs/genética , RNA Antissenso/genética , RNA Longo não Codificante/genética , Semaforinas/genética , Neoplasias Gástricas/patologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/genética , Cárdia/metabolismo , Movimento Celular , Proliferação de Células , Metilação de DNA , Progressão da Doença , Sinergismo Farmacológico , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Taxa de Sobrevida , Células Tumorais Cultivadas
13.
Angiogenesis ; 19(1): 95-106, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26625874

RESUMO

Fatty acid-binding proteins (FABP) are small molecular mass intracellular lipid chaperones that are expressed in a tissue-specific manner with some overlaps. FABP4 and FABP5 share ~55 % amino acid sequence homology and demonstrate synergistic effects in regulation of metabolic and inflammatory responses in adipocytes and macrophages. Recent studies have shown that FABP4 and FABP5 are also co-expressed in a subset of endothelial cells (EC). FABP4, which has a primarily microvascular distribution, enhances angiogenic responses of ECs, including proliferation, migration, and survival. However, the vascular expression of FABP5 has not been well characterized, and the role of FABP5 in regulation of angiogenic responses in ECs has not been studied to date. Herein we report that while FABP4 and FABP5 are co-expressed in microvascular ECs in several tissues, FABP5 expression is also detected in ECs of larger blood vessels. In contrast to FABP4, EC-FABP5 levels are not induced by VEGF-A or bFGF. FABP5 deficiency leads to a profound impairment in EC proliferation and chemotactic migration. These effects are recapitulated in an ex vivo assay of angiogenesis, the aortic ring assay. Interestingly, in contrast to FABP4-deficient ECs, FABP5-deficient ECs are significantly more resistant to apoptotic cell death. The effect of FABP5 on EC proliferation and survival is mediated, only in part, by PPARδ-dependent pathways. Collectively, these findings demonstrate that EC-FABP5, similar to EC-FABP4, promotes angiogenic responses under certain conditions, but it can also exert opposing effects on EC survival as compared to EC-FABP4. Thus, the balance between FABP4 and FABP5 in ECs may be important in regulation of angiogenic versus quiescent phenotypes in blood vessels.


Assuntos
Linhagem da Célula , Proteínas de Ligação a Ácido Graxo/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Metabolismo dos Lipídeos , Proteínas de Neoplasias/metabolismo , Neovascularização Fisiológica , Animais , Aorta/fisiologia , Morte Celular , Proliferação de Células , Sobrevivência Celular , Quimiotaxia , Citoproteção , Proteínas de Ligação a Ácido Graxo/deficiência , Células Endoteliais da Veia Umbilical Humana/citologia , Técnicas In Vitro , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Neoplasias/deficiência , PPAR delta/metabolismo
14.
Appl Environ Microbiol ; 82(1): 318-27, 2016 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26497454

RESUMO

Bacillopeptidase F (Bpr) is a fibrinolytic serine protease produced by Bacillus subtilis. Its precursor is composed of a signal peptide, an N-terminal propeptide, a catalytic domain, and a long C-terminal extension (CTE). Several active forms of Bpr have been previously reported, but little is known about the maturation of this enzyme. Here, a gene encoding a Bpr (BprL) was cloned from B. subtilis LZW and expressed in B. subtilis WB700, and three fibrinolytic mature forms with apparent molecular masses of 45, 75, and 85 kDa were identified in the culture supernatant. After treatment with urea, the 75-kDa mature form had the same molecular mass as the 85-kDa mature form, from which we infer that they adopt different conformations. Mutational analysis revealed that while the 85-kDa mature form is generated via heterocatalytic processing of a BprL proform by an unidentified protease of B. subtilis, the production of the 75- and 45-kDa mature forms involves both hetero- and autocatalytic events. From in vitro analysis of BprL and its sequential C-terminal truncation variants, it appears that partial removal of the CTE is required for the initiation of autoprocessing of the N-terminal propeptide, which is composed of a core domain (N*) and a 15-residue linker peptide, thereby yielding the 45-kDa mature form. These data suggest that the differential processing of BprL, either heterocatalytically or autocatalytically, leads to the formation of multiple mature forms with different molecular masses or conformations.


Assuntos
Bacillus subtilis/enzimologia , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Microbiologia do Solo , Sequência de Aminoácidos , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/genética , Bacillus subtilis/fisiologia , Biocatálise , Domínio Catalítico , Clonagem Molecular , Escherichia coli/genética , Fibrinólise , Dados de Sequência Molecular , Mutação , Peptídeos/metabolismo , Dobramento de Proteína , Modificação Traducional de Proteínas , Serina Endopeptidases/genética , Ureia/farmacologia
15.
J Environ Sci (China) ; 45: 18-27, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27372115

RESUMO

Al substitution in goethite is common in soils, and has strong influence on the structure and physicochemical properties of goethite. In this research, a series of Al-doped goethites were synthesized, and characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR) and extended X-ray absorption fine structure (EXAFS) spectroscopy. The adsorption behavior of these samples towards PO4(3-) was also investigated. Characterization results demonstrated that increasing Al content in goethite led to a reduction in crystallinity, increase in specific surface area (SSA), and morphology change from needle-like to granular. Rietveld structure refinement revealed that the lattice parameter a remained almost constant and b slightly decreased, but c was significantly reduced, and the calculated crystal density increased. EXAFS analysis demonstrated that the Fe(Al)-O distance in the structure of the doped goethites was almost the same, but the Fe-Fe(Al) distance decreased with increasing Al content. Surface analysis showed that, with increasing Al content, the content of OH groups on the mineral surface increased. The adsorption of phosphate per unit mass of Al-doped goethite increased, while adsorption per unit area decreased owing to the decrease of the relative proportion of (110) facets in the total surface area of the minerals. The results of this research facilitate better understanding of the effect of Al substitution on the structure and properties of goethite and the cycling of phosphate in the environment.


Assuntos
Alumínio/química , Compostos de Ferro/química , Minerais/química , Fosfatos/química , Absorção Fisico-Química , Microscopia Eletrônica de Transmissão , Modelos Químicos , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
16.
Neuropathol Appl Neurobiol ; 41(5): 646-56, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24865546

RESUMO

AIM: Arteriovenous malformations (AVM) and cavernous malformations (CM) are the most commonly encountered cerebral vascular malformations, which are dynamic lesions with de novo growth potentials. Postnatal angiogenesis and vasculogenesis have been postulated to play a role in the pathogenesis of these malformations. Fatty acid binding protein 4 (FABP4) is an intracellular lipid chaperone, which is expressed in a subset of endothelial cells. FABP4 enhances the angiogenic responses of endothelial cells and is not expressed in normal cerebral vasculature. Herein, we investigated the hypothesis that FABP4 expression may be up-regulated in AVM and CM. METHODS: The abundance of FABP4 expression was analysed by immunohistochemistry on 35 paraffin-embedded AVM and CM sections. FABP4-expressing cells were further characterized by double immunofluorescence using antibodies against various cell-specific markers. RESULTS: Heterogenous FABP4 expression was detected in 100% AVM and 78% of CM samples. Endothelial cell FABP4 expression was present in 65% and 43% of AVM and CM, respectively. Interestingly, a population of FABP4-positive perivascular cells was detected in 100% of AVM and 86% of CM sections examined. These cells were negative for markers of macrophages and smooth muscle cells, but expressed vimentin, a marker of mesenchymal cells, including fibroblasts. CONCLUSION: FABP4 expression is detected in AVM and CM in a subset of endothelial cells and some perivascular fibroblast-like vimentin-positive cells.


Assuntos
Neoplasias do Sistema Nervoso Central/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Hemangioma Cavernoso do Sistema Nervoso Central/metabolismo , Neovascularização Patológica/metabolismo , Malformações Vasculares/metabolismo , Adolescente , Idoso , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Criança , Pré-Escolar , Células Endoteliais/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Remodelação Vascular , Adulto Jovem
17.
J Biol Chem ; 288(48): 34826-38, 2013 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-24145031

RESUMO

The proform of the WF146 protease, an extracellular subtilase produced by thermophilic Bacillus sp. WF146, matures efficiently at high temperatures. Here we report that the proform, which contains an N-terminal propeptide composed of a core domain (N*) and a linker peptide, is intrinsically able to mature via multiple pathways. One autocatalytic pathway is initiated by cis-processing of N* to generate an autoprocessed complex N*-I(WT), and this step is followed by truncation of the linker peptide and degradation of N*. Another autocatalytic pathway is initiated by trans-processing of the linker peptide followed by degradation of N*. Unlike most reported subtilases, the maturation of the WF146 protease occurs not only autocatalytically but also hetero-catalytically whereby heterogeneous proteases accelerate the maturation of the WF146 protease via trans-processing of the proform and N*-I(WT). Although N* acts as an intramolecular chaperone and an inhibitor of the mature enzyme, the linker peptide is susceptible to proteolysis, allowing the trans-processing reaction to occur auto- and hetero-catalytically. These studies also demonstrate that the WF146 protease undergoes subtle structural adjustments during the maturation process and that the binding of Ca(2+) is required for routing the proform to mature properly at high temperatures. Interestingly, under Ca(2+)-free conditions, the proform is cis-processed into a unique propeptide-intermediate complex (N*-I(E)) capable of re-synthesis of the proform. Based on the basic catalytic principle of serine proteases and these experimental results, a mechanism for the cis-processing/re-synthesis equilibrium of the proform and the role of the linker peptide in regulation of this equilibrium has been proposed.


Assuntos
Bacillus/enzimologia , Estabilidade Proteica , Serina Proteases/química , Subtilisinas/química , Sequência de Aminoácidos , Catálise , Regulação Bacteriana da Expressão Gênica , Temperatura Alta , Mutagênese , Peptídeos/química , Dobramento de Proteína , Processamento de Proteína Pós-Traducional , Serina Proteases/metabolismo , Subtilisinas/genética , Subtilisinas/metabolismo
18.
J Nanosci Nanotechnol ; 14(9): 7307-14, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25924407

RESUMO

The heterogeneous UV/Fenton degradation of tetrabromobisphenol A (TBBPA) catalyzed by nanocrystalline Fe3O4 and Fe2.04Cr0.96O4 was investigated, with focus on the influence of UV light and initial pH, degradation pathways and effect of Cr substation. The catalysts were prepared by a precipitation-oxidation method and characterized by chemical analysis, XRD, XAFS, TG-DSC, BET surface area and magnetometer. At pH 6.7 and under UV irradiation, almost complete degradation of TBBPA by Fe2.04Cr0.96O4 was accomplished within 240 min, and the leaching Fe ions were negligible. The substitution of chromium greatly increased the BET specific surface area and surface hydroxyl amount, which improved the heterogeneous UV/Fenton catalytic activity of magnetite. Moreover, Cr3+ on the octahedral sites enhanced the electron transfer process in the magnetite structure to accelerate the *OH generation. The produced *OH radicals preferentially attacked the C-Br bonds of TBBPA and then ß-cleavaged the C-C bonds between benzene rings and isopropyl groups. The above results are of great significance for well understanding the effect of transition metal substitution on the UV/Fenton catalytic activity of magnetite and prospecting the application of magnetite minerals in environmental purification.


Assuntos
Cromo/química , Nanopartículas Metálicas/química , Nanopartículas/química , Bifenil Polibromatos/química , Poluentes Químicos da Água/química , Recuperação e Remediação Ambiental , Bifenil Polibromatos/análise , Raios Ultravioleta , Poluentes Químicos da Água/análise
19.
J Infect Dis ; 208(11): 1803-12, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23908488

RESUMO

BACKGROUND: Sepsis and sepsis-associated organ failure are devastating conditions. Understanding the detailed cellular/molecular mechanisms involved in sepsis should lead to the identification of novel therapeutic targets. METHODS: Cecal ligation and puncture (CLP) was used as a polymicrobial sepsis model in vivo to determine mortality and end-organ damage. Macrophages were adopted as the cellular model in vitro for mechanistic studies. RESULTS: PTRF+/- mice survived longer and suffered less organ damage after CLP. Reductions in nitric oxide (NO) and iNOS biosynthesis were observed in plasma, macrophages, and vital organs in the PTRF+/- mice. Using an acute sepsis model after CLP, we found that iNOS-/- mice had a comparable level of survival as the PTRF+/- mice. Similarly, polymerase I transcript release factor (PTRF) deficiency resulted in decreased iNOS and NO/ROS production in macrophages in vitro. Mechanistically, lipopolysaccharide (LPS) enhanced the co-localization and interaction between PTRF and TLR4 in lipid rafts. Deletion of PTRF blocked formation of the TLR4/Myd88 complex after LPS. Consistent with this, lack of PTRF impaired the TLR4 signaling, as shown by the decreased p-JNK, p-ERK, and p-p38, which are upstream factors involved in iNOS transcription. CONCLUSION: PTRF is a crucial regulator of TLR4 signaling in the development of sepsis.


Assuntos
Ceco/cirurgia , Proteínas de Ligação a RNA/metabolismo , Sepse/imunologia , Transdução de Sinais , Animais , Ceco/imunologia , Linhagem Celular , Modelos Animais de Doenças , Ligadura , Lipopolissacarídeos/metabolismo , Fígado/patologia , Macrófagos/citologia , Macrófagos/imunologia , Masculino , Microdomínios da Membrana/metabolismo , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/metabolismo , Óxido Nítrico/análise , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Punções , Proteínas de Ligação a RNA/genética , Espécies Reativas de Oxigênio/metabolismo , Sepse/microbiologia , Sepse/mortalidade , Deleção de Sequência , Organismos Livres de Patógenos Específicos , Receptor 4 Toll-Like/metabolismo
20.
Sci Total Environ ; 932: 173013, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38719041

RESUMO

As a highly effective broad-spectrum antibacterial agent, triclosan (TCS) is widely used in personal care and medical disinfection products, resulting in its widespread occurrence in aquatic and terrestrial environments, and even in the human body. Notably, the use of TCS surged during the COVID-19 outbreak, leading to increasing environmental TCS pollution pressure. From the perspective of environmental health, it is essential to systematically understand the environmental occurrence and behavior of TCS, its toxicological effects on biota and humans, and technologies to remove TCS from the environment. This review comprehensively summarizes the current knowledge regarding the sources and behavior of TCS in surface water, groundwater, and soil systems, focusing on its toxicological effects on aquatic and terrestrial organisms. Effluent from wastewater treatment plants is the primary source of TCS in aquatic systems, whereas sewage application and/or wastewater irrigation are the major sources of TCS in soil. Human exposure pathways to TCS and associated adverse outcomes were also analyzed. Skin and oral mucosal absorption, and dietary intake are important TCS exposure pathways. Reducing or completely degrading TCS in the environment is important for alleviating environmental pollution and protecting public health. Therefore, this paper reviews the removal mechanisms, including adsorption, biotic and abiotic redox reactions, and the influencing factors. In addition, the advantages and disadvantages of the different techniques are compared, and development prospects are proposed. These findings provide a basis for the management and risk assessment of TCS and are beneficial for the application of treatment technology in TCS removal.


Assuntos
Triclosan , Triclosan/toxicidade , Humanos , Anti-Infecciosos Locais , Poluentes Químicos da Água/análise , Monitoramento Ambiental
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA