Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 65
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Anal Chem ; 96(6): 2341-2350, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38300877

RESUMO

Multiplex assay has emerged as a robust and versatile method for the simultaneous detection of multiple analytes in a single test. However, challenges in terms of poor accuracy and complexity remained. In this work, we developed a multiplex aptamer-based fluorescence assay using magnetism-encoded nanoparticles for the simultaneous detection of multiple pathogenic bacteria. The encapsulation of different amounts of Fe3O4 nanoparticles in zeolitic imidazolate framework-90 (ZIF-90) leads to the formation of Fe3O4@ZIF-90 (FZ) composites with distinct magnetism strengths. By functionalizing a specific aptamer on the surface of the FZ composites, target bacteria can be specifically and precisely separated from a mixed sample in a sequential manner. This property allows for the simultaneous quantitative analysis of multiple target bacteria by using a single-color fluorescence label, thereby resulting in minimal spectral crosstalk interference and improved accuracy. The successful determination of multiple bacteria in contaminated milk samples demonstrates the applicability of this multiplex assay in complex biological matrices. Compared to conventional multiplex fluorescence assays, this approach offers distinct advantages of simplicity, efficiency, and implementation. We believe that this study can provide valuable insights into the development of the multiplex assay while introducing a new method for the simultaneous detection of multiple bacteria.


Assuntos
Aptâmeros de Nucleotídeos , Estruturas Metalorgânicas , Nanopartículas , Limite de Detecção , Bactérias
2.
Bioorg Chem ; 147: 107412, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38696845

RESUMO

The development of novel topoisomerase I (TOP1) inhibitors is crucial for overcoming the drawbacks and limitations of current TOP1 poisons. Here, we identified two potential TOP1 inhibitors, namely, FTY720 (a sphingosine 1-phosphate antagonist) and COH29 (a ribonucleotide reductase inhibitor), through experimental screening of known active compounds. Biological experiments verified that FTY720 and COH29 were nonintercalative TOP1 catalytic inhibitors that did not induce the formation of DNA-TOP1 covalent complexes. Molecular docking revealed that FTY720 and COH29 interacted favorably with TOP1. Molecular dynamics simulations revealed that FTY720 and COH29 could affect the catalytic domain of TOP1, thus resulting in altered DNA-binding cavity size. The alanine scanning and interaction entropy identified Arg536 as a hotspot residue. In addition, the bioinformatics analysis predicted that FTY720 and COH29 could be effective in treating malignant breast tumors. Biological experiments verified their antitumor activities using MCF-7 breast cancer cells. Their combinatory effects with TOP1 poisons were also investigated. Further, FTY720 and COH29 were found to cause less DNA damage compared with TOP1 poisons. The findings provide reliable lead compounds for the development of novel TOP1 catalytic inhibitors and offer new insights into the potential clinical applications of FTY720 and COH29 in targeting TOP1.


Assuntos
Antineoplásicos , DNA Topoisomerases Tipo I , Cloridrato de Fingolimode , Simulação de Acoplamento Molecular , Inibidores da Topoisomerase I , Humanos , Cloridrato de Fingolimode/farmacologia , Cloridrato de Fingolimode/química , Cloridrato de Fingolimode/síntese química , DNA Topoisomerases Tipo I/metabolismo , DNA Topoisomerases Tipo I/química , Inibidores da Topoisomerase I/farmacologia , Inibidores da Topoisomerase I/química , Inibidores da Topoisomerase I/síntese química , Estrutura Molecular , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células/efeitos dos fármacos , Simulação de Dinâmica Molecular , Células MCF-7
3.
Appl Microbiol Biotechnol ; 108(1): 40, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38175236

RESUMO

Folic acid deficiency is common worldwide and is linked to an imbalance in gut microbiota. However, based on model animals used to study the utilization of folic acid by gut microbes, there are challenges of reproducibility and individual differences. In this study, an in vitro fecal slurry culture model of folic acid deficiency was established to investigate the effects of supplementation with 5-methyltetrahydrofolate (MTHF) and non-reduced folic acid (FA) on the modulation of gut microbiota. 16S rRNA sequencing results revealed that both FA (29.7%) and MTHF (27.9%) supplementation significantly reduced the relative abundance of Bacteroidetes compared with control case (34.3%). MTHF supplementation significantly improved the relative abundance of Firmicutes by 4.49%. Notably, compared with the control case, FA and MTHF supplementation promoted an increase in fecal levels of Lactobacillus, Bifidobacterium, and Pediococcus. Short-chain fatty acid (SCFA) analysis showed that folic acid supplementation decreased acetate levels and increased fermentative production of isobutyric acid. The in vitro fecal slurry culture model developed in this study can be utilized as a model of folic acid deficiency in humans to study the gut microbiota and demonstrate that exogenous folic acid affects the composition of the gut microbiota and the level of SCFAs. KEY POINTS: • Establishment of folic acid deficiency in an in vitro culture model. • Folic acid supplementation regulates intestinal microbes and SCFAs. • Connections between microbes and SCFAs after adding folic acid are built.


Assuntos
Deficiência de Ácido Fólico , Microbioma Gastrointestinal , Animais , Humanos , Ácido Fólico , Fermentação , RNA Ribossômico 16S/genética , Reprodutibilidade dos Testes , Ácidos Graxos Voláteis
4.
J Sci Food Agric ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38666511

RESUMO

BACKGROUND: Folate is crucial for maintaining health, but humans are unable to synthesize folate and need to obtain it from food. Lactiplantibacillus plantarum can produce the necessary vitamin B for the human body, including folate. Whole genome sequencing technology can clarify the physiological characteristics of folate production in Lactiplantibacillus plantarum. In order to explore new Lactiplantibacillus plantarum that produce folate, the folate production and probiotic characteristics of Lactiplantibacillus plantarum ZFM55 isolated from infant feces were investigated, and whole genome sequencing was performed. RESULTS: The folate synthesis ability of Lactiplantibacillus plantarum ZFM55 were measured, and its total folate production was 299.72 ± 28.81 ng mL-1. Subsequently, its probiotic properties were explored. The antibacterial test showed that its inhibition zone diameter against Staphylococcus aureus and Salmonella typhimurium was 15.5 ± 0.82 mm and 13.88 ± 0.98 mm, respectively. The tolerance test results indicated that it maintained good activity in simulated gastrointestinal tract and bile salt environments. In vitro intestinal simulation experiments had confirmed that Lactiplantibacillus plantarum ZFM55 can increase the abundance of beneficial bacteria such as Bifidobacteria in the intestine and inhibit the growth of harmful bacteria such as Escherichia_Shigella. Genomic sequencing indicated that the genetic material of Lactiplantibacillus plantarum ZFM55 contains one chromosome and three plasmids, and it has 20 genes related to folate synthesis, which explains its ability to produce folate. CONCLUSION: This study reports a new potential probiotic that produces folate, and provides ideas for exploring probiotics with specific probiotic characteristics. © 2024 Society of Chemical Industry.

5.
Europace ; 25(3): 1008-1014, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36610066

RESUMO

AIMS: The aim of this study was to investigate the electrophysiological characteristics and long-term outcome of patients undergoing substrate-based ablation of left posterior fascicular ventricular tachycardia (LPF-VT) guided by targeting of fragmented antegrade Purkinje potentials (FAPs) during sinus rhythm. METHODS AND RESULTS: This study retrospectively analysed 50 consecutive patients referred for ablation. Substrate mapping during sinus rhythm was performed to identify the FAP that was targeted by ablation. FAPs were recorded in 48 of 50 (96%) patients during sinus rhythm. The distribution of FAPs was located at the proximal segment of posterior septal left ventricle (LV) in two (4.2%) patients, middle segment in 33 (68.8%) patients, and distal segment in 13 (27.1%) patients. In 32 of 48 (66.7%) patients, the FAP displayed a continuous multicomponent fragmented electrogram, while a fragmented, split, and uncoupled electrogram was recorded in 16 (33.3%) patients. Entrainment attempts at FAP region were performed successfully in seven patients, demonstrating concealed fusion and the critical isthmus of LPF-VT. Catheter ablation targeting at the FAPs successfully terminated the LPF-VT in all 48 patients in whom they were seen. Left posterior fascicular (LPF) block occurred in four (8%) patients after ablation. During a median follow-up period of 61.2 ± 16.8 months, 47 of 50 (94%) patients remained free from recurrent LPF-VT. CONCLUSION: Ablation of LPF-VT targeting FAP during sinus rhythm results in excellent long-term clinical outcome. FAPs were commonly located at the middle segment of posterior septal LV. Region with FAPs during sinus rhythm was predictive of critical site for re-entry.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/cirurgia , Taquicardia Ventricular/etiologia , Ventrículos do Coração , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Eletrocardiografia
6.
Plant Cell Rep ; 43(1): 16, 2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38135839

RESUMO

KEY MESSAGE: PtrANR1 positively regulates plant drought tolerance by increasing proline level and reducing ROS accumulation. PtrANR1 directly activates PtrAUX1 expression to promote root growth and improve plant drought tolerance. Citrus quality and yield are severely declined under drought stress. To date, the effects of MADS-box family transcription factors (TFs) on plant drought resistance have made some progress. However, whether MADS-box family TFs are associated with citrus drought response has remained unclear. The current paper identified a MADS-box family gene PtrANR1 encoding anthocyanidin reductase from trifoliate orange. PtrANR1 exhibits high identities with ANR1 proteins found in various plants. PtrANR1 possesses two conserved domains known as MADS and kertanin-like domains. PtrANR1 is a nuclear protein which has transactivation activity. A significant induction of PtrANR1 transcript was detected in leaves and roots of trifoliate orange treated with PEG6000 and ABA. Under drought stress, Arabidopsis ectopic overexpressing PtrANR1 exhibited obviously elevated contents of proline, ABA and IAA, better developed root, enhanced antioxidant enzyme activities, as well as notably reduced accumulation of malondialdehyde (MDA) and reactive oxygen species (ROS) compared with WT plants. However, opposite change trends of these physiological indices were detected in PtrANR1 homolog silencing lemon. Furthermore, transgenic Arabidopsis displayed significantly increased expression levels in genes associated with ABA, IAA and proline production, IAA polar transport, ROS elimination and drought response. However, these genes exhibited noticeably decreased transcript levels in PtrANR1 homolog silencing lemon. Moreover, PtrANR1 could increase IAA content and promote root growth by binding to GArG-box in the promoter of PtrAUX1 to activate its transcript. These findings indicated that PtrANR1 had a beneficial impact on plant drought resistance through promoting root development, increasing proline accumulation and scavenging of ROS.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Secas , Plantas Geneticamente Modificadas/genética , Antioxidantes/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Prolina/metabolismo , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Arabidopsis/genética
7.
BMC Surg ; 23(1): 25, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36709302

RESUMO

AIM: The present study aimed to identify risk factors for venous thromboembolism (VTE) after pancreaticoduodenectomy (PD) and to develop and internally validate a predictive model for the risk of venous thrombosis. METHODS: We retrospectively collected data from 352 patients who visited our hospital to undergo PD from January 2018 to March 2022. The number of patients recruited was divided in an 8:2 ratio by using the random split method, with 80% of the patients serving as the training set and 20% as the validation set. The least absolute shrinkage and selection operator (Lasso) regression model was used to optimize feature selection for the VTE risk model. Multivariate logistic regression analysis was used to construct a prediction model by incorporating the features selected in the Lasso model. C-index, receiver operating characteristic curve, calibration plot, and decision curve were used to assess the accuracy of the model, to calibrate the model, and to determine the clinical usefulness of the model. Finally, we evaluated the prediction model for internal validation. RESULTS: The predictors included in the prediction nomogram were sex, age, gastrointestinal symptoms, hypertension, diabetes, operative method, intraoperative bleeding, blood transfusion, neutrophil count, prothrombin time (PT), activated partial thromboplastin time (APTT), aspartate aminotransferase (AST)/alanine aminotransferase (ALT) ratio (AST/ALT), and total bilirubin (TBIL). The model showed good discrimination with a C-index of 0.827, had good consistency based on the calibration curve, and had an area under the ROC curve value of 0.822 (P < 0.001, 95%confidence interval:0.761-0.882). A high C-index value of 0.894 was reached in internal validation. Decision curve analysis showed that the VTE nomogram was clinically useful when intervention was decided at the VTE possibility threshold of 10%. CONCLUSION: The novel model developed in this study is highly targeted and enables personalized assessment of VTE occurrence in patients who undergo PD. The predictors are easily accessible and facilitate the assessment of patients by clinical practitioners.


Assuntos
Pancreaticoduodenectomia , Tromboembolia Venosa , Humanos , Pancreaticoduodenectomia/efeitos adversos , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Estudos Retrospectivos , Fatores de Risco , Análise Fatorial , Nomogramas
8.
J Sci Food Agric ; 103(15): 7694-7701, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37439279

RESUMO

BACKGROUND: Folic acid is a class of B vitamins that have the function of improving intestinal microbiota. RESULT: Lactiplantibacillus plantarum LZ227, which is a highly folate-producing strain, was used as the research object, and the folic acid produced by LZ227 was further identified by liquid chromatography-mass spectrometry, and the structural diversity, community composition, abundance difference, and short-chain fatty acids content in fermentation broth were studied by the manure slurry fermentation model. The results showed that the folic acid produced by LZ227 was 5-methyltetrahydrofolate. CONCLUSION: LZ227 can increase the intestinal microbial diversity in the folate-free state, regulate the intestinal flora, increase the abundance of Firmicutes in the intestinal flora, and inhibit the abundance of Bacteroidetes. LZ227 can inhibit the growth of Alistipes, Parabacteroides, and Bacteroides in the intestine. LZ227 significantly reduced the acetic acid content and significantly increased the butyric acid content in the folate-free case. © 2023 Society of Chemical Industry.


Assuntos
Microbioma Gastrointestinal , Complexo Vitamínico B , Ácido Fólico , Intestinos , Firmicutes , Bacteroidetes
9.
Mol Biol Rep ; 49(4): 2857-2867, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35067814

RESUMO

BACKGROUND: Intestinal ischemia-reperfusion (I/R) causes severe injury to the intestine, leading to systemic inflammation and multiple organ failure. Autophagy is a stress-response mechanism that can protect against I/R injury by removing damaged organelles and toxic protein aggregates. Recent evidence has identified JAK-STAT signaling pathway as a new regulator of autophagy process, however, their regulatory relationship in intestinal I/R remains unknown. METHODS AND RESULTS: We systematically analyzed intestinal transcriptome data and found that JAK-STAT pathway was largely activated in response to I/R with most significant upregulation observed for JAK2 and STAT3. ChIP-Seq and luciferase assays in an in vitro oxygen-glucose deprivation and reoxygenation model revealed that activated JAK2/STAT3 signaling directly inhibited the transcription of autophagy regulator Beclin-1, leading to the suppression of autophagy and the activation of intestinal cell death. These findings were further confirmed in an in vivo mouse model, in which, intestinal I/R injury was associated with the activation of JAK2/STAT3 pathway and the deactivation of Beclin-1-mediated autophagy, while inhibiting JAK2/STAT3 with AG490 reactivated autophagy and improved survival after intestinal I/R injury. CONCLUSIONS: JAK2/STAT3 signaling suppresses autophagy process during intestinal I/R, while inhibiting JAK-STAT can be protective against intestinal I/R injury by activating autophagy. These findings expand our knowledge on intestinal I/R injury and provide therapeutic targets for clinical treatment.


Assuntos
Janus Quinases , Traumatismo por Reperfusão , Animais , Apoptose , Autofagia , Intestinos , Janus Quinase 2/metabolismo , Janus Quinases/metabolismo , Camundongos , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Fatores de Transcrição STAT/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
10.
Int J Mol Sci ; 23(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36499381

RESUMO

Drought limits citrus yield and fruit quality worldwide. The basic helix-loop-helix (bHLH) transcription factors (TFs) are involved in plant response to drought stress. However, few bHLH TFs related to drought response have been functionally characterized in citrus. In this study, a bHLH family gene, named PtrbHLH66, was cloned from trifoliate orange. PtrbHLH66 contained a highly conserved bHLH domain and was clustered closely with bHLH66 homologs from other plant species. PtrbHLH66 was localized to the nucleus and had transcriptional activation activity. The expression of PtrbHLH66 was significantly induced by polyethylene glycol 6000 (PEG6000) and abscisic acid (ABA) treatments. Ectopic expression of PtrbHLH66 promoted the seed germination and root growth, increased the proline and ABA contents and the activities of antioxidant enzymes, but reduced the accumulation of malondialdehyde (MDA) and reactive oxygen species (ROS) under drought stress, resulting in enhanced drought tolerance of transgenic Arabidopsis. In contrast, silencing the PtrbHLH66 homolog in lemon plants showed the opposite effects. Furthermore, under drought stress, the transcript levels of 15 genes involved in ABA biosynthesis, proline biosynthesis, ROS scavenging and drought response were obviously upregulated in PtrbHLH66 ectopic-expressing Arabidopsis but downregulated in PtrbHLH66 homolog silencing lemon. Thus, our results suggested that PtrbHLH66 acted as a positive regulator of plant drought resistance by regulating root growth and ROS scavenging.


Assuntos
Arabidopsis , Poncirus , Arabidopsis/metabolismo , Poncirus/genética , Poncirus/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Resistência à Seca , Estresse Fisiológico/genética , Ácido Abscísico/metabolismo , Secas , Prolina/metabolismo
11.
Zhongguo Zhong Yao Za Zhi ; 47(11): 3073-3087, 2022 Jun.
Artigo em Zh | MEDLINE | ID: mdl-35718532

RESUMO

Network Meta-analysis was performed to systematically compare the efficacy of different Chinese patent medicines for activating blood and resolving stasis in the treatment of endometriosis and to provide evidence-based references for clinical medication regimens. The relevant randomized controlled trials(RCTs) involving Chinese patent medicines combined with conventional treatment(experimental group) vs conventional treatment(control group) were retrieved from Chinese and English literature databases. The bias risk assessment tool recommended in Cochrane handbook 5.3 was used to evaluate the quality of the included studies. The result data of each outcome index was extracted for network Meta-analysis in Stata 15.0. A total of 44 RCTs were included in this study, involving 4 345 patients and 9 Chinese patent medicines. The network Meta-analysis revealed the following trends.(1)In terms of reducing the visual analogue scale(VAS) scores, Dan'e Fukang Plaster+conventional treatment>Xuefu Zhuyu Capsules+conventional treatment>Gongliuxiao Capsules+conventional treatment.(2)In terms of reducing cancer antigen CA125, Xiaojin Capsules+conventional treatment>Shaofu Zhuyu Granules+conventional treatment>Dan'e Fukang Plaster+conventional treatment.(3)In terms of reducing estradiol(E_2), Gongliuxiao Capsules+conventional treatment>Xiaojin Capsules+conventional treatment>Sanjie Zhentong Capsules+conventional treatment.(4) In terms of reducing recurrence rate, Guizhi Fuling Capsules+conventional treatment>Xuefu Zhuyu Capsules+conventional treatment>Dan'e Fukang Plaster+conventional treatment. The peroral Chinese patent medicines for activating blood and resolving stasis combined with conventional treatment have better efficacy in the treatment of endometriosis than conventional treatment. However, considering the low quality of the included literature, large-scale high-quality clinical trials are needed in the future research.


Assuntos
Medicamentos de Ervas Chinesas , Endometriose , Cápsulas , China , Medicamentos de Ervas Chinesas/uso terapêutico , Endometriose/tratamento farmacológico , Feminino , Humanos , Metanálise em Rede , Medicamentos sem Prescrição/uso terapêutico
12.
Connect Tissue Res ; 62(5): 531-541, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-32686499

RESUMO

BACKGROUND: Bioinformatics analysis was performed on gene expression profile microarray data to identify the key genes activated through the TNF-α/TNFR1 signaling pathway in intervertebral disc degeneration (IDD). The common differentially expressed genes (co-DEGs) were calculated in nucleus pulposus (NP) cells and annulus fibrosus (AF) cells under TNF-α treatment or TNFR1 knockdown, which reveals the potential mechanism of TNF-α involvement in IDD and may provide new therapeutic targets for IDD. METHODS: Differentially expressed genes (DEGs) in TNF-α-treated or TNFR1-knockdown NP cells and AF cells were identified. Further analysis of the gene ontology (GO), signaling pathways and interaction networks of the DEGs or co-DEGs were conducted using the Database for Annotation, Visualization and Integrated Discovery, STRING Database, and Cytoscape software. The relationship between genes and musculoskeletal diseases, including IDD, was assessed with the Comparative Toxicogenomics Database. The predicted microRNAs corresponding to the co-DEGs were also identified by microRNA Data Integration Portal. RESULTS: In NP cells, the DEGs (|log2FoldChange|>2, adj.P < 0.01) were identified including 48 DEGs by TNF-α treatment and 74 DEGs by TNFR1 knockdown; in AF cells, correspondingly, 105 DEGs were identified. The co-DEGs between NP cells and AF cells were calculated including CXCL8, ICAM1, BIRC3, RELB, NFKBIA, and TNFAIP3. They may be the hub genes that were significantly associated with both NP cells and AF cells through the TNF-α/TNFR1 signaling pathway. The co-DEGs and corresponding predicted miRNAs may be potential therapeutic targets for IDD. CONCLUSIONS: CXCL8, ICAM1, BIRC3, RELB, NFKBIA, and TNFAIP3 may have a synergistic effect on TNF-α-induced IDD development.Abbreviations: IDD: Intervertebral disc degeneration; NP: Nucleus pulposus; AF: Annulus fibrosus; co-DEG: Common differentially expressed gene; GO: Gene Ontology; KEGG: Kyoto Encyclopedia of Genes and Genomes; PPI: Protein-protein interaction.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Biologia Computacional , Perfilação da Expressão Gênica , Humanos , Degeneração do Disco Intervertebral/genética , MicroRNAs , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Fator de Necrose Tumoral alfa/genética
13.
Neurocomputing (Amst) ; 458: 232-245, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34121811

RESUMO

The outbreak and rapid spread of coronavirus disease 2019 (COVID-19) has had a huge impact on the lives and safety of people around the world. Chest CT is considered an effective tool for the diagnosis and follow-up of COVID-19. For faster examination, automatic COVID-19 diagnostic techniques using deep learning on CT images have received increasing attention. However, the number and category of existing datasets for COVID-19 diagnosis that can be used for training are limited, and the number of initial COVID-19 samples is much smaller than the normal's, which leads to the problem of class imbalance. It makes the classification algorithms difficult to learn the discriminative boundaries since the data of some classes are rich while others are scarce. Therefore, training robust deep neural networks with imbalanced data is a fundamental challenging but important task in the diagnosis of COVID-19. In this paper, we create a challenging clinical dataset (named COVID19-Diag) with category diversity and propose a novel imbalanced data classification method using deep supervised learning with a self-adaptive auxiliary loss (DSN-SAAL) for COVID-19 diagnosis. The loss function considers both the effects of data overlap between CT slices and possible noisy labels in clinical datasets on a multi-scale, deep supervised network framework by integrating the effective number of samples and a weighting regularization item. The learning process jointly and automatically optimizes all parameters over the deep supervised network, making our model generally applicable to a wide range of datasets. Extensive experiments are conducted on COVID19-Diag and three public COVID-19 diagnosis datasets. The results show that our DSN-SAAL outperforms the state-of-the-art methods and is effective for the diagnosis of COVID-19 in varying degrees of data imbalance.

14.
J Cell Physiol ; 235(7-8): 5736-5749, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31975410

RESUMO

An imbalance between matrix synthesis and degradation is the hallmark of intervertebral disc degeneration while inflammatory cytokines contribute to the imbalance. Bromodomain and extra-terminal domain (BET) family is associated with the pathogenesis of inflammation, and inhibition of BRD4, a vital member of BET family, plays an anti-inflammatory role in many diseases. However, it remains elusive whether BRD4 plays a similar role in nucleus pulposus (NP) cells and participates in the pathogenesis of intervertebral disc degeneration. The present study aims to observe whether BRD4 inhibition regulates matrix metabolism by controlling autophagy and NLRP3 inflammasome activity. Besides, the relationship was investigated among nuclear factor κB (NF-κB) signaling, autophagy and NLRP3 inflammasome in NP cells. Here, real-time polymerase chain reaction, western blot analysis and adenoviral GFP-LC3 vector transduction in vitro were used, and it was revealed that BRD4 inhibition alleviated the matrix degradation and increased autophagy in the presence or absence of tumor necrosis factor α. Moreover, p65 knockdown or treatment with JQ1 and Bay11-7082 demonstrated that BRD4 inhibition attenuated NLRP3 inflammasome activity through NF-κB signaling, while autophagy inhibition by bafilomycin A1 promoted matrix degradation and NLRP3 inflammasome activity in NP cells. In addition, analysis of BRD4 messenger RNA expression in human NP tissues further verified the destructive function of BRD4. Simply, BRD4 inhibition alleviates matrix degradation by enhancing autophagy and suppressing NLRP3 inflammasome activity through NF-κB signaling in NP cells.


Assuntos
Inflamação/genética , Degeneração do Disco Intervertebral/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteínas Nucleares/genética , Fator de Transcrição RelA/genética , Fatores de Transcrição/genética , Animais , Autofagia/genética , Azepinas/farmacologia , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamassomos/efeitos dos fármacos , Inflamação/patologia , Degeneração do Disco Intervertebral/patologia , Macrolídeos/farmacologia , NF-kappa B/genética , Núcleo Pulposo/metabolismo , Núcleo Pulposo/patologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Triazóis/farmacologia
15.
Phytother Res ; 34(11): 2857-2866, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32578328

RESUMO

The metabolic syndrome (MetS) is one of the major health hazards and an epidemic worldwide. There is no known best remedy has been defined yet. In the current investigation, we designed a meta-analysis of randomized clinical trials (RCTs) to evaluate the beneficial effects of tea consumption in alleviating metabolic syndromes. Herein, we accumulated the relevant literature available on PubMed and EMBASE databases from January, 2000 to August, 2019. RCTs bearing impact factor of at least 1 or more were studied for the effect of tea consumption on MetS. This meta-analysis suggested that tea consumption has beneficial effects on diastolic blood pressure (DBP), and this finding was characterized of all types of tea in the current study and also for body mass index (BMI) value. Furthermore, this analysis also found that black tea consumption has protective effects on systolic SBP, green tea reduces the incidence of diabetes and lower the level of low-density lipoprotein (LDL) cholesterol. These functions required BMI value at least 28 or higher. The meta data led us to conclude that tea consumption have protective effects on MetS, however, different types of tea might have different protective mechanisms on MetS, but, exact mechanisms are not yet clear and needs to be explored.


Assuntos
Síndrome Metabólica/tratamento farmacológico , Chá/química , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
16.
Sensors (Basel) ; 20(18)2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32962241

RESUMO

Compressed sensing provides an elegant framework for recovering sparse signals from compressed measurements. This paper addresses the problem of sparse signal reconstruction from compressed measurements that is more robust to complex, especially non-Gaussian noise, which arises in many applications. For this purpose, we present a method that exploits the maximum negentropy theory to promote the adaptability to noise. This problem is formalized as a constrained minimization problem, where the objective function is the negentropy of measurement error with sparse constraint -norm. On the minimization issue of the problem, although several promising algorithms have been proposed in the literature, they are very computationally demanding and thus cannot be used in many practical situations. To improve on this, we propose an efficient algorithm based on a fast iterative shrinkage-thresholding algorithm that can converge fast. Both the theoretical analysis and numerical experiments show the better accuracy and convergent rate of the proposed method.

17.
Langmuir ; 34(4): 1340-1346, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29293350

RESUMO

The quality of nanoparticle dispersion in a polymer matrix significantly influences the macroscopic properties of the composite material. Like general polymer-nanoparticle composites, electrospun nanofiber nanoparticle composites do not have an adopted quantitative model for dispersion throughout the polymer matrix, often relying on a qualitative assessment. Being such an influential property, quantifying dispersion is essential for the process of optimization and understanding the factors influencing dispersion. Here, a simulation model was developed to quantify the effects of nanoparticle volume loading (ϕ) and fiber-to-particle diameter ratios (D/d) on the dispersion in an electrospun nanofiber based on the interparticle distance. A dispersion factor is defined to quantify the dispersion along the polymer fiber. In the dilute regime (ϕ < 20%), three distinct regions of the dispersion factor were defined with the highest quality dispersion shown to occur when geometric constraints limit fiber volume accessibility. This model serves as a standard for comparison for future experimental studies and dispersion models through its comparability with microscopy techniques and as a way to quantify and predict dispersion in electrospinning polymer-nanoparticle systems with a single performance metric.

18.
Lancet Oncol ; 18(7): 863-873, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28592387

RESUMO

BACKGROUND: Dabrafenib plus trametinib improves clinical outcomes in BRAFV600-mutant metastatic melanoma without brain metastases; however, the activity of dabrafenib plus trametinib has not been studied in active melanoma brain metastases. Here, we report results from the phase 2 COMBI-MB trial. Our aim was to build on the current body of evidence of targeted therapy in melanoma brain metastases through an evaluation of dabrafenib plus trametinib in patients with BRAFV600-mutant melanoma brain metastases. METHODS: This ongoing, multicentre, multicohort, open-label, phase 2 study evaluated oral dabrafenib (150 mg twice per day) plus oral trametinib (2 mg once per day) in four patient cohorts with melanoma brain metastases enrolled from 32 hospitals and institutions in Europe, North America, and Australia: (A) BRAFV600E-positive, asymptomatic melanoma brain metastases, with no previous local brain therapy, and an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1; (B) BRAFV600E-positive, asymptomatic melanoma brain metastases, with previous local brain therapy, and an ECOG performance status of 0 or 1; (C) BRAFV600D/K/R-positive, asymptomatic melanoma brain metastases, with or without previous local brain therapy, and an ECOG performance status of 0 or 1; and (D) BRAFV600D/E/K/R-positive, symptomatic melanoma brain metastases, with or without previous local brain therapy, and an ECOG performance status of 0, 1, or 2. The primary endpoint was investigator-assessed intracranial response in cohort A in the all-treated-patients population. Secondary endpoints included intracranial response in cohorts B, C, and D. This study is registered with ClinicalTrials.gov, number NCT02039947. FINDINGS: Between Feb 28, 2014, and Aug 5, 2016, 125 patients were enrolled in the study: 76 patients in cohort A; 16 patients in cohort B; 16 patients in cohort C; and 17 patients in cohort D. At the data cutoff (Nov 28, 2016) after a median follow-up of 8·5 months (IQR 5·5-14·0), 44 (58%; 95% CI 46-69) of 76 patients in cohort A achieved an intracranial response. Intracranial response by investigator assessment was also achieved in nine (56%; 95% CI 30-80) of 16 patients in cohort B, seven (44%; 20-70) of 16 patients in cohort C, and ten (59%; 33-82) of 17 patients in cohort D. The most common serious adverse events related to study treatment were pyrexia for dabrafenib (eight [6%] of 125 patients) and decreased ejection fraction (five [4%]) for trametinib. The most common grade 3 or worse adverse events, regardless of study drug relationship, were pyrexia (four [3%] of 125) and headache (three [2%]). INTERPRETATION: Dabrafenib plus trametinib was active with a manageable safety profile in this melanoma population that was consistent with previous dabrafenib plus trametinib studies in patients with BRAFV600-mutant melanoma without brain metastases, but the median duration of response was relatively short. These results provide evidence of clinical benefit with dabrafenib plus trametinib and support the need for additional research to further improve outcomes in patients with melanoma brain metastases. FUNDING: Novartis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Melanoma/tratamento farmacológico , Proteínas Proto-Oncogênicas B-raf/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundário , Feminino , Febre/induzido quimicamente , Cefaleia/induzido quimicamente , Humanos , Imidazóis/administração & dosagem , Imidazóis/efeitos adversos , Imageamento por Ressonância Magnética , Masculino , Melanoma/diagnóstico por imagem , Melanoma/genética , Melanoma/secundário , Pessoa de Meia-Idade , Mutação , Oximas/administração & dosagem , Oximas/efeitos adversos , Estudos Prospectivos , Piridonas/administração & dosagem , Piridonas/efeitos adversos , Pirimidinonas/administração & dosagem , Pirimidinonas/efeitos adversos , Volume Sistólico/efeitos dos fármacos , Adulto Jovem
19.
Heliyon ; 10(7): e29024, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596015

RESUMO

This study investigated the seat layout of automobile interiors and its impact on the fluidity and privacy of interior space using spatial perception and space syntax research methods. The interior of an automobile is a typical "miniature" passenger space. First, to explore the perception characteristics of interior space fluidity and privacy across different seat configurations, we conducted a perception experiment on the interior space of seven automobile models with various seat layouts. The depth, connection, global integration degree, and standardized integration degree values were obtained using spatial syntax to perform topological calculations on the experimental automobile models. We conducted a correlation analysis in conjunction with the results of the perception experiment and the spatial syntax analysis. The calculation results of spatial syntax analysis are consistent with the experimental results of perception of automobile interior space layout on the fluidity and privacy. The different layout of automobile seats can affect people's perception on the fluidity and privacy of automobile interior space. At the same time, spatial syntax can provide an effective design analysis tool for the fluidity and privacy of automobile interior space.

20.
Cortex ; 175: 54-65, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38704919

RESUMO

The dorsal attention network (DAN) is a network of brain regions essential for attentional orienting, which includes the lateral intraparietal area (LIP) and frontal eye field (FEF). Recently, the putative human dorsal posterior infero-temporal area (phPITd) has been identified as a new node of the DAN. However, its functional relationship with other areas of the DAN and its specific role in visual attention remained unclear. In this study, we analyzed a large publicly available neuroimaging dataset to investigate the intrinsic functional connectivities (FCs) of the phPITd with other brain areas. The results showed that the intrinsic FCs of the phPITd with the areas of the visual network and the DAN were significantly stronger than those with the ventral attention network (VAN) areas and areas of other networks. We further conducted individual difference analyses with a sample size of 295 participants and a series of attentional tasks to investigate which attentional components each phPITd-based DAN edge predicts. Our findings revealed that the intrinsic FC of the left phPITd with the LIPv could predict individual ability in attentional orienting, but not in alerting, executive control, and distractor suppression. Our results not only provide direct evidence of the phPITd's functional relationship with the LIPv, but also offer a comprehensive understanding of its specific role in visual attention.


Assuntos
Atenção , Mapeamento Encefálico , Imageamento por Ressonância Magnética , Lobo Temporal , Percepção Visual , Humanos , Atenção/fisiologia , Masculino , Feminino , Adulto , Lobo Temporal/fisiologia , Lobo Temporal/diagnóstico por imagem , Adulto Jovem , Imageamento por Ressonância Magnética/métodos , Percepção Visual/fisiologia , Orientação/fisiologia , Lobo Parietal/fisiologia , Lobo Parietal/diagnóstico por imagem , Rede Nervosa/fisiologia , Rede Nervosa/diagnóstico por imagem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA