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1.
J Chem Phys ; 160(18)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38716850

RESUMO

Using the density functional theory, we conducted a study on the electrification upon contact between hydrophobic liquid molecules and water molecules, revealing localized characteristics of contact-electrification. These "localized features" refer to the specific microscale characteristics where electron transfer predominantly occurs at the contact regions, influenced by factors such as atomic distances and molecular orientations. Although the electrostatic potential and the highest occupied molecular orbital-lowest unoccupied molecular orbital gap offer substantial predictive insights for electron transfer across polymer interfaces, they fall short in capturing the complexities associated with the interaction between hydrophobic liquids and water molecules. The electronegativity of elements at the interface and the localization of molecular orbitals play a decisive role in electron transfer. Simultaneously, for liquid molecules with irregular structures, there is no correlation between the "contact area" and the amount of electron transfer. The "contact area" refers to the surface region where two different liquid molecules come into close proximity. It is defined by the surface area of atoms with interatomic distances smaller than the van der Waals radius. This study challenges traditional assumptions about contact-electrification, particularly in liquid-liquid interfaces, providing new insights into the localized nature of this phenomenon.

2.
BMC Plant Biol ; 23(1): 602, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38031030

RESUMO

BACKGROUND: Leymus chinensis (L. chinensis) is a perennial native forage grass widely distributed in the steppe of Inner Mongolia as the dominant species. Calcium (Ca) is an essential mineral element important for plant adaptation to the growth environment. Ca limitation was previously shown to strongly inhibit Arabidopsis (Arabidopsis thaliana) seedling growth and disrupt plasma membrane stability and selectivity, increasing fluid-phase-based endocytosis and contents of all major membrane lipids. RESULTS: In this study, we investigated the significance of Ca for L. chinensis growth and membrane stability relative to Arabidopsis. Our results showed that Ca limitation did not affect L. chinensis seedling growth and endocytosis in roots. Moreover, the plasma membrane maintained high selectivity. The lipid phosphatidylcholine (PC): phosphatidylethanolamine (PE) ratio, an indicator of the membrane stability, was five times higher in L. chinensis than in Arabidopsis. Furthermore, in L. chinensis, Ca limitation did not affect the content of any major lipid types, decreased malondialdehyde (MDA) content, and increased superoxide dismutase (SOD) activity, showing an opposite pattern to that in Arabidopsis. L. chinensis roots accumulated higher contents of PC, phosphatidylinositol (PI), monogalactosyldiacylglycerol (MGDG), phosphatidylglycerol (PG), cardiolipin (CL), digalactosyldiacylglycerol (DGDG), and lysophosphatidylcholine (LPC) but less phosphatidylethanolamine (PE), diacylglycerol (DAG), triacylglycerolv (TAG), phosphatidylserine (PS), lysobisphosphatidic acids (LPAs), lysophosphatidylethanolamine (LPE), and lysophosphatidylserine (LPS) than Arabidopsis roots. Moreover, we detected 31 and 66 unique lipids in L. chinensis and Arabidopsis, respectively. CONCLUSIONS: This study revealed that L. chinensis roots have unique membrane lipid composition that was not sensitive to Ca limitation, which might contribute to the wider natural distribution of this species.


Assuntos
Arabidopsis , Arabidopsis/metabolismo , Cálcio/metabolismo , Fosfatidiletanolaminas/metabolismo , Lipídeos de Membrana/metabolismo , Poaceae/metabolismo
3.
J Digit Imaging ; 36(2): 739-752, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36474089

RESUMO

The Dice similarity coefficient (DSC) is both a widely used metric and loss function for biomedical image segmentation due to its robustness to class imbalance. However, it is well known that the DSC loss is poorly calibrated, resulting in overconfident predictions that cannot be usefully interpreted in biomedical and clinical practice. Performance is often the only metric used to evaluate segmentations produced by deep neural networks, and calibration is often neglected. However, calibration is important for translation into biomedical and clinical practice, providing crucial contextual information to model predictions for interpretation by scientists and clinicians. In this study, we provide a simple yet effective extension of the DSC loss, named the DSC++ loss, that selectively modulates the penalty associated with overconfident, incorrect predictions. As a standalone loss function, the DSC++ loss achieves significantly improved calibration over the conventional DSC loss across six well-validated open-source biomedical imaging datasets, including both 2D binary and 3D multi-class segmentation tasks. Similarly, we observe significantly improved calibration when integrating the DSC++ loss into four DSC-based loss functions. Finally, we use softmax thresholding to illustrate that well calibrated outputs enable tailoring of recall-precision bias, which is an important post-processing technique to adapt the model predictions to suit the biomedical or clinical task. The DSC++ loss overcomes the major limitation of the DSC loss, providing a suitable loss function for training deep learning segmentation models for use in biomedical and clinical practice. Source code is available at https://github.com/mlyg/DicePlusPlus .


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Humanos , Processamento de Imagem Assistida por Computador/métodos
4.
Inf Fusion ; 82: 99-122, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35664012

RESUMO

Removing the bias and variance of multicentre data has always been a challenge in large scale digital healthcare studies, which requires the ability to integrate clinical features extracted from data acquired by different scanners and protocols to improve stability and robustness. Previous studies have described various computational approaches to fuse single modality multicentre datasets. However, these surveys rarely focused on evaluation metrics and lacked a checklist for computational data harmonisation studies. In this systematic review, we summarise the computational data harmonisation approaches for multi-modality data in the digital healthcare field, including harmonisation strategies and evaluation metrics based on different theories. In addition, a comprehensive checklist that summarises common practices for data harmonisation studies is proposed to guide researchers to report their research findings more effectively. Last but not least, flowcharts presenting possible ways for methodology and metric selection are proposed and the limitations of different methods have been surveyed for future research.

5.
Entropy (Basel) ; 24(10)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37420344

RESUMO

Accurate clustering is a challenging task with unlabeled data. Ensemble clustering aims to combine sets of base clusterings to obtain a better and more stable clustering and has shown its ability to improve clustering accuracy. Dense representation ensemble clustering (DREC) and entropy-based locally weighted ensemble clustering (ELWEC) are two typical methods for ensemble clustering. However, DREC treats each microcluster equally and hence, ignores the differences between each microcluster, while ELWEC conducts clustering on clusters rather than microclusters and ignores the sample-cluster relationship. To address these issues, a divergence-based locally weighted ensemble clustering with dictionary learning (DLWECDL) is proposed in this paper. Specifically, the DLWECDL consists of four phases. First, the clusters from the base clustering are used to generate microclusters. Second, a Kullback-Leibler divergence-based ensemble-driven cluster index is used to measure the weight of each microcluster. With these weights, an ensemble clustering algorithm with dictionary learning and the L2,1-norm is employed in the third phase. Meanwhile, the objective function is resolved by optimizing four subproblems and a similarity matrix is learned. Finally, a normalized cut (Ncut) is used to partition the similarity matrix and the ensemble clustering results are obtained. In this study, the proposed DLWECDL was validated on 20 widely used datasets and compared to some other state-of-the-art ensemble clustering methods. The experimental results demonstrated that the proposed DLWECDL is a very promising method for ensemble clustering.

6.
J Pathol ; 252(1): 53-64, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32542677

RESUMO

Identification of glomerular lesions and structures is a key point for pathological diagnosis, treatment instructions, and prognosis evaluation in kidney diseases. These time-consuming tasks require a more accurate and reproducible quantitative analysis method. We established derivation and validation cohorts composed of 400 Chinese patients with immunoglobulin A nephropathy (IgAN) retrospectively. Deep convolutional neural networks and biomedical image processing algorithms were implemented to locate glomeruli, identify glomerular lesions (global and segmental glomerular sclerosis, crescent, and none of the above), identify and quantify different intrinsic glomerular cells, and assess a network-based mesangial hypercellularity score in periodic acid-Schiff (PAS)-stained slides. Our framework achieved 93.1% average precision and 94.9% average recall for location of glomeruli, and a total Cohen's kappa of 0.912 [95% confidence interval (CI), 0.892-0.932] for glomerular lesion classification. The evaluation of global, segmental glomerular sclerosis, and crescents achieved Cohen's kappa values of 1.0, 0.776, 0.861, and 95% CI of (1.0, 1.0), (0.727, 0.825), (0.824, 0.898), respectively. The well-designed neural network can identify three kinds of intrinsic glomerular cells with 92.2% accuracy, surpassing the about 5-11% average accuracy of junior pathologists. Statistical interpretation shows that there was a significant difference (P value < 0.0001) between this analytic renal pathology system (ARPS) and four junior pathologists for identifying mesangial and endothelial cells, while that for podocytes was similar, with P value = 0.0602. In addition, this study indicated that the ratio of mesangial cells, endothelial cells, and podocytes within glomeruli from IgAN was 0.41:0.36:0.23, and the performance of mesangial score assessment reached a Cohen's kappa of 0.42 and 95% CI (0.18, 0.69). The proposed computer-aided diagnosis system has feasibility for quantitative analysis and auxiliary recognition of glomerular pathological features. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Assuntos
Aprendizado Profundo , Glomerulonefrite por IGA/patologia , Nefropatias/diagnóstico , Glomérulos Renais/patologia , Células Mesangiais/patologia , Podócitos/patologia , Adulto , Diagnóstico por Computador , Feminino , Humanos , Nefropatias/patologia , Masculino , Redes Neurais de Computação
7.
Future Oncol ; 17(24): 3203-3216, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33947216

RESUMO

Aim: We aimed at investigating the mechanism of RAB1A proliferation and invasion in gliomas. Materials & methods: Genome-wide expression profile data and immunohistochemistry were analyzed to assess RAB1A expression in gliomas. The Transwell assay, wound healing assay, brain slice coculture model, cellular fluorescence and intracranial xenograft model of nude mice were used to determine the proliferation and invasion of glioma cells. Results & conclusion: RAB1A was highly expressed in gliomas compared with normal brain tissue. The overall survival time of glioma patients with high RAB1A expression was significantly shortened. RAB1A regulated the activity of RAC1 by inhibiting the mTOR signaling pathway, affecting actin polymerization, cell morphology and cell polarity. RAB1A downregulation inhibited the epithelial-mesenchymal transition, proliferation and invasion of glioma cells.


Assuntos
Neoplasias Encefálicas/patologia , Transição Epitelial-Mesenquimal/fisiologia , Glioma/patologia , Serina-Treonina Quinases TOR/metabolismo , Proteínas rab1 de Ligação ao GTP/metabolismo , Animais , Proliferação de Células/fisiologia , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Invasividade Neoplásica/patologia , Transdução de Sinais/fisiologia
8.
J Cell Physiol ; 234(7): 10671-10679, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30480816

RESUMO

Aberrant expressions of long noncoding RNAs (lncRNAs) contribute to carcinogenesis via regulating tumor suppressors or oncogenes. LncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) has been recognized as an oncogene to promote tumor progression of many cancers. However, the function of NEAT1 in glioma remains poorly discovered. Currently, we focused on the role of NEAT1 in glioma. Here, we found that NEAT1 was greatly upregulated in glioma cells compared with normal human astrocytes (NHAs). Meanwhile, miR-107 was significantly downregulated in glioma cell lines. Then, we observed that knockdown of NEAT1 suppressed the growth and invasion of glioma cells including U251 and SW1783 cells. Reversely, overexpression of NEAT1 dramatically induced glioma cell survival, increased cell colony formation, and promoted cell invasion ability. Subsequently, bioinformatics analysis was performed to predict the correlation between NEAT1 and miR-107. Moreover, it was revealed that NEAT1 could modulate miR-107 via serving as an endogenous sponge of miR-107. The direct binding correlation between NEAT1 and miR-107 was validated in our study. In addition, cyclin dependent kinase 14 (CDK14) was predicted as an messenger RNA target of miR-107 and the association between them was confirmed in our research. Moreover, we implied that NEAT1 demonstrated its biological functions via regulating miR-107 and CDK14 in vivo. In summary, our findings indicated that NEAT1/miR-107/CDK14 axis participated in glioma development. NEAT1 could act as a significant prognostic biomarker in glioma progression.


Assuntos
Quinases Ciclina-Dependentes/genética , Glioma/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Apoptose/genética , Astrócitos/metabolismo , Astrócitos/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Silenciamento de Genes , Glioma/patologia , Humanos , Invasividade Neoplásica/genética , Ligação Proteica
9.
J Cell Biochem ; 120(11): 18762-18770, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31265172

RESUMO

In human, there are two myxovirus resistance genes-MX1 and MX2, which respectively encode MXA and MXB protein. For MXB, it was traditionally deemed to work in the progression of cell cycle and adjustment of nuclear import. Thus, we speculated that it might play important roles in tumor progression. The purpose of this study was to preliminarily explore the underlying functions and mechanism of the MX2 gene on glioblastoma multiforme. Quantitative reverse transcription polymerase chain reaction, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT), and transwell experiments were to detect the relative MX2 mRNA level and its biological functions on glioma cells, respectively. The data displayed that MX2 was obviously downregulated both in glioblastoma (GBM) and GBM cell lines, meanwhile, its overexpression could markedly reduce cell proliferation, migration, and invasion of glioma cells, implying that it was related with glioblastoma progression. In addition, the overall survival of patient with glioblastoma had a negative correlation with the MX2 expression. Then, Western blot indicated the potential mechanism of MX2 in glioblastoma. We found that MX2 overexpression could decrease the relative levels of phosphorylated-ERK1/2 (p-ERK1/2), p-p38, and nuclear factor-κB (NF-κB), while have no effects on extracellular signal-regulated kinase (ERK), p38, and lamin B1. Moreover, the influences of MX2 overexpression on cell proliferation, migration, and invasion could be weakened by the three inhibitors (PD98059, SB203580, and (pyridin-2-ylmethyl) dithiocarbamate [PDTC]). These results implied that MX2 might suppress the proliferation and metastasis of glioma cells by manipulating the ERK/P38/NF-κB signaling pathway. In conclusion, MX2 is potential to be a new marker used for glioblastoma prognosis or a new target for glioblastoma treatments.


Assuntos
Movimento Celular/genética , Proliferação de Células/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glioblastoma/genética , Proteínas de Resistência a Myxovirus/genética , NF-kappa B/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Flavonoides/farmacologia , Regulação Neoplásica da Expressão Gênica , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Imidazóis/farmacologia , Proteínas de Resistência a Myxovirus/metabolismo , Invasividade Neoplásica , Fosforilação , Prolina/análogos & derivados , Prolina/farmacologia , Piridinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Tiocarbamatos/farmacologia
10.
Small ; 15(45): e1903520, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31529764

RESUMO

Much attention is paid to metal lithium as a hopeful negative material for reversible batteries with a high specific capacity. Although applying 3D hosts can relieve the dendrite growth to some extent, gradient-distributed lithium ion in 3D uniform hosts still induces uncontrolled lithium dendrites growth, especially at high lithium capacity and high current density. Herein, a 3D conductive carbon nanofiber framework with gradient-distributed ZnO particles as nucleation seeds (G-CNF) to regulate lithium deposition is proposed. Based on such a unique structure, the G-CNF electrode exhibits a high average Coulombic efficiency (CE) of 98.1% for 700 cycles at 0.5 mA cm-2 . Even at 5 mA cm-2 , the G-CNF electrode performs a stable cycling process and high CE of 96.0% for over 200 cycles. When the lithium-deposited G-CNF (G-CNF-Li) anode is applied in a full cell with a commercial LiFePO4 cathode, it exhibits a stable capacity of 115 mAh g-1 and high retention of 95.7% after 300 cycles. Through inducing the gradient-distributed nucleation seeds to counter the existing Li-ion concentration polarization, a uniform and stable lithium deposition process in the 3D host is achieved even under the condition of high current density.

11.
Heart Surg Forum ; 22(6): E448-E451, 2019 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-31895028

RESUMO

BACKGROUND: To describe staging surgery for the treatment of a patient with aortic arch aneurysm combined with aberrant bilateral subclavian artery, persistent left superior vena cava (PLSVC), and airway compression. CASE REPORT: A 42-year-old female was hospitalized for aortic arch aneurysm involving aberrant bilateral subclavian artery, PLSVC, and airway compression. The patient's aneurysm was successfully treated by stage I surgery, including total aortic arch replacement and stented elephant trunk procedure and stage II surgery, including tracheal stenting and tracheotomy. Aortic CTA examination showed an unobstructed lumen and a good stent position without tracheal stent migration. Regular postoperative follow-up showed no complications, such as dyspnea, cough, and sputum, or other discomfort symptoms. CONCLUSIONS: Total aortic arch replacement, elephant trunk surgery, and second-stage tracheal stent surgery are effective and safe for the treatment of aortic arch aneurysm combined with aberrant bilateral subclavian artery, PLSVC, and airway compression.


Assuntos
Obstrução das Vias Respiratórias/cirurgia , Aorta Torácica/cirurgia , Aneurisma Aórtico/cirurgia , Anormalidades Cardiovasculares/cirurgia , Procedimentos Cirúrgicos Cardiovasculares , Artéria Subclávia/anormalidades , Veia Cava Superior/anormalidades , Veia Cava Superior/cirurgia , Adulto , Obstrução das Vias Respiratórias/etiologia , Aneurisma Aórtico/complicações , Feminino , Humanos , Stents , Artéria Subclávia/cirurgia , Traqueia/cirurgia , Resultado do Tratamento
12.
Mol Plant Microbe Interact ; 31(2): 260-273, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29068240

RESUMO

Cutinases have been implicated as important enzymes during the process of fungal infection of aerial plant organs. The function of cutinases in the disease cycle of fungal pathogens that invade plants through the roots has been less studied. Here, functional analysis of 13 cutinase (carbohydrate esterase family 5 domain-containing) genes (VdCUTs) in the highly virulent vascular wilt pathogen Verticillium dahliae Vd991 was performed. Significant sequence divergence in cutinase family members was observed in the genome of V. dahliae Vd991. Functional analyses demonstrated that only VdCUT11, as purified protein, induced cell death and triggered defense responses in Nicotiana benthamiana, cotton, and tomato plants. Virus-induced gene silencing showed that VdCUT11 induces plant defense responses in Nicotiana benthamania in a BAK1 and SOBIR-dependent manner. Furthermore, coinfiltration assays revealed that the carbohydrate-binding module family 1 protein (VdCBM1) suppressed VdCUT11-induced cell death and other defense responses in N. benthamiana. Targeted deletion of VdCUT11 in V. dahliae significantly compromised virulence on cotton plants. The cutinase VdCUT11 is an important secreted enzyme and virulence factor that elicits plant defense responses in the absence of VdCBM1.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Gossypium/imunologia , Gossypium/microbiologia , Verticillium/enzimologia , Sequência de Aminoácidos , Regulação Fúngica da Expressão Gênica , Filogenia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Nicotiana , Verticillium/metabolismo , Verticillium/patogenicidade , Virulência
13.
New Phytol ; 217(2): 756-770, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29084346

RESUMO

Verticillium dahliae isolates are most virulent on the host from which they were originally isolated. Mechanisms underlying these dominant host adaptations are currently unknown. We sequenced the genome of V. dahliae Vd991, which is highly virulent on its original host, cotton, and performed comparisons with the reference genomes of JR2 (from tomato) and VdLs.17 (from lettuce). Pathogenicity-related factor prediction, orthology and multigene family classification, transcriptome analyses, phylogenetic analyses, and pathogenicity experiments were performed. The Vd991 genome harbored several exclusive, lineage-specific (LS) genes within LS regions (LSRs). Deletion mutants of the seven genes within one LSR (G-LSR2) in Vd991 were less virulent only on cotton. Integration of G-LSR2 genes individually into JR2 and VdLs.17 resulted in significantly enhanced virulence on cotton but did not affect virulence on tomato or lettuce. Transcription levels of the seven LS genes in Vd991 were higher during the early stages of cotton infection, as compared with other hosts. Phylogenetic analyses suggested that G-LSR2 was acquired from Fusarium oxysporum f. sp. vasinfectum through horizontal gene transfer. Our results provide evidence that horizontal gene transfer from Fusarium to Vd991 contributed significantly to its adaptation to cotton and may represent a significant mechanism in the evolution of an asexual plant pathogen.


Assuntos
Fusarium/genética , Transferência Genética Horizontal , Genoma Fúngico , Genômica , Gossypium/microbiologia , Verticillium/genética , Verticillium/patogenicidade , Fatores de Virulência/metabolismo , Sequência de Bases , Evolução Molecular , Interações Hospedeiro-Patógeno/genética , Lactuca/microbiologia , Solanum lycopersicum/microbiologia , Família Multigênica , Filogenia , Especificidade da Espécie , Sintenia/genética , Virulência/genética
14.
Bioorg Med Chem Lett ; 28(11): 2029-2034, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29748051

RESUMO

Compound 5 (SCH772984) was identified as a potent inhibitor of ERK1/2 with excellent selectivity against a panel of kinases (0/231 kinases tested @ 100 nM) and good cell proliferation activity, but suffered from poor PK (rat AUC PK @10 mpk = 0 µM h; F% = 0) which precluded further development. In an effort to identify novel ERK inhibitors with improved PK properties with respect to 5, a systematic exploration of sterics and composition at the 3-position of the pyrrolidine led to the discovery of a novel 3(S)-thiomethyl pyrrolidine analog 28 with vastly improved PK (rat AUC PK @10 mpk = 26 µM h; F% = 70).


Assuntos
Antineoplásicos/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Pirrolidinas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Pirrolidinas/síntese química , Pirrolidinas/química , Ratos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
15.
Int J Neurosci ; 128(3): 243-254, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28918695

RESUMO

Purpose/Aim: Animal models of traumatic brain injury (TBI) provide powerful tools to study TBI in a controlled, rigorous and cost-efficient manner. The mostly used animals in TBI studies so far are rodents. However, compared with rodents, large animals (e.g. swine, rabbit, sheep, ferret, etc.) show great advantages in modeling TBI due to the similarity of their brains to human brain. The aim of our review was to summarize the development and progress of common large animal TBI models in past 30 years. MATERIALS AND METHODS: Mixed published articles and books associated with large animal models of TBI were researched and summarized. RESULTS: We majorly sumed up current common large animal models of TBI, including discussion on the available research methodologies in previous studies, several potential therapies in large animal trials of TBI as well as advantages and disadvantages of these models. CONCLUSIONS: Large animal models of TBI play crucial role in determining the underlying mechanisms and screening putative therapeutic targets of TBI.


Assuntos
Lesões Encefálicas Traumáticas , Modelos Animais de Doenças , Animais , Humanos
16.
Environ Microbiol ; 19(5): 1914-1932, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28205292

RESUMO

Glycoside hydrolase 12 (GH12) proteins act as virulence factors and pathogen-associated molecular patterns (PAMPs) in oomycetes. However, the pathogenic mechanisms of fungal GH12 proteins have not been characterized. In this study, we demonstrated that two of the six GH12 proteins produced by the fungus Verticillium dahliae Vd991, VdEG1 and VdEG3 acted as PAMPs to trigger cell death and PAMP-triggered immunity (PTI) independent of their enzymatic activity in Nicotiana benthamiana. A 63-amino-acid peptide of VdEG3 was sufficient for cell death-inducing activity, but this was not the case for the corresponding peptide of VdEG1. Further study indicated that VdEG1 and VdEG3 trigger PTI in different ways: BAK1 is required for VdEG1- and VdEG3-triggered immunity, while SOBIR1 is specifically required for VdEG1-triggered immunity in N. benthamiana. Unlike oomycetes, which employ RXLR effectors to suppress host immunity, a carbohydrate-binding module family 1 (CBM1) protein domain suppressed GH12 protein-induced cell death. Furthermore, during infection of N. benthamiana and cotton, VdEG1 and VdEG3 acted as PAMPs and virulence factors, respectively indicative of host-dependent molecular functions. These results suggest that VdEG1 and VdEG3 associate differently with BAK1 and SOBIR1 receptor-like kinases to trigger immunity in N. benthamiana, and together with CBM1-containing proteins manipulate plant immunity.


Assuntos
Glicosídeo Hidrolases/metabolismo , Gossypium/microbiologia , Nicotiana/microbiologia , Imunidade Vegetal/fisiologia , Receptores de Superfície Celular/metabolismo , Verticillium/patogenicidade , Morte Celular , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Verticillium/metabolismo , Fatores de Virulência/metabolismo
17.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1862(12): 1512-1519, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28919478

RESUMO

Statins have been proven to be effective in treating non-alcoholic fatty liver disease (NAFLD). Recently, it was reported that statins decreased the hepatic expression of perilipin 5 (Plin5), a lipid droplet (LD)-associated protein, which plays critical roles in regulating lipid accumulation and lipolysis in liver. However, the function and regulation mechanism of Plin5 have not yet been well-established in NAFLD treatment with statins. In this study, we observed that atorvastatin moderately reduced the expression of Plin5 in livers without changing the protein level of Plin5 in the hepatic LD fraction of mice fed with high-fat diet (HFD). Intriguingly, atorvastatin stimulated the PKA-mediated phosphorylation of Plin5 and reduced the triglyceride (TG) accumulation in hepatocytes with overexpression of wide type (Plin5-WT) compared to serine-155 mutant Plin5 (Plin5-S155A). Moreover, PKA-stimulated FA release of purified LDs carrying Plin5-WT but not Plin5-S155A. Glucagon, a PKA activator, stimulated the phosphorylation of Plin5-WT and inhibited its interaction with CGI-58. The results indicated that atorvastatin promoted lipolysis and reduced TG accumulation in the liver by increasing PKA-mediated phosphorylation of Plin5. This new mechanism of lipid-lowering effects of atorvastatin might provide a new strategy for NAFLD treatment.


Assuntos
Atorvastatina/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipólise/efeitos dos fármacos , Fígado/metabolismo , Proteínas Musculares/metabolismo , Triglicerídeos/metabolismo , Substituição de Aminoácidos , Animais , Proteínas Quinases Dependentes de AMP Cíclico/genética , Gorduras na Dieta/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Lipólise/genética , Fígado/patologia , Masculino , Camundongos , Camundongos Knockout , Proteínas Musculares/genética , Mutação de Sentido Incorreto , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Triglicerídeos/genética
18.
Tumour Biol ; 39(7): 1010428317705575, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28677425

RESUMO

Recently, we have demonstrated that IKBKE (inhibitor of nuclear factor kappa-B kinase subunit epsilon) is overexpressed in human glioblastoma and that inhibition of IKBKE remarkably suppresses the proliferative and invasive behaviour of glioblastoma cells. However, the specific pathogenic molecular mechanism remains to be elucidated. In this study, we verified that IKBKE promotes YAP1 expression via posttranslational modification and accelerates YAP1 translocation to the nucleus for the development of glioblastoma. We then determined that YAP1 negatively regulates miR-let-7b/i by overexpressing and silencing YAP1 expression. In addition, miR-let-7b/i feedback decreases the expression of IKBKE and YAP1 and suppresses the transportation of YAP1 located in the nucleus. Therefore, the regulatory feedback circuit of IKBKE↑→YAP1↑→miR-let-7b/i↓→IKBKE↑ dictates glioblastoma progression. Thus, we propose that blocking the circuit may be a new therapeutic strategy for the treatment of glioblastoma.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Glioblastoma/genética , Quinase I-kappa B/genética , MicroRNAs/genética , Fosfoproteínas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Retroalimentação Fisiológica , Regulação Neoplásica da Expressão Gênica , Glioblastoma/patologia , Humanos , Invasividade Neoplásica/genética , Fatores de Transcrição , Proteínas de Sinalização YAP
19.
BMC Anesthesiol ; 17(1): 126, 2017 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-28893201

RESUMO

BACKGROUND: During facemask ventilation, gastric insufflation is defined as appearance of a comet-tail or an acoustic shadow on ultrasonography. Ultrasonographic measurement of antral cross-section area (CSA) may reflect an insufflated antrum and provide interesting semi-quantitative data in regard to the gastric insufflation. This study aimed to determine the appropriate level of inspiratory pressure sufficient to provide adequate pulmonary ventilation with a lower occurrence of gastric insufflation during facemask pressure-controlled ventilation using real-time ultrasonography in paralyzed children. METHODS: Ninety children, ASA I-II, aged from 2 to 4 years, scheduled for general anesthesia were enrolled in this randomized and double-blinded study. Children were randomized into one of the five groups (P8, P10, P12, P14, and P16) defined by the applied inspiratory pressure during facemask ventilation: 8, 10, 12, 14, and 16 cm H2O. Anesthesia induction was conducted with fentanyl and propofol. Rocuronium was administrated as a muscle relaxant. After rocuronium administration, facemask ventilation was performed for 120 s. Gastric insufflation (GI+) was detected by ultrasonography, and the antral CSA before and after facemask ventilation were also measured using ultrasonography. Respiratory variables were monitored. RESULTS: Gastric insufflation was detected in 32 children (3/18 in group P8, 5/18 in group P10, 7/18 in group P12, 8/16 in group P14, and 9/14 in group P16). The antral CSA after facemask ventilation statistically increased in subgroups P14 GI+ and P16 GI+ for whom gastric insufflation was detected by ultrasonography, whereas it did not change statistically in other groups. Lung ventilation was inadequate for group P8 or P10. CONCLUSION: We concluded that an inspiratory pressure of 12 cm H2O is sufficient to provide adequate ventilation with a lower occurrence of gastric insufflation during induction of general anesthesia in paralyzed Chinese children aged from 2 to 4 years old. TRIAL REGISTRATION: ( ChiCTR-IPR-16007960 ). Registered 21 February 2016 Conclusion heading: Ultrasound for determining gastric insufflation.


Assuntos
Anestesia Geral/normas , Sistemas Computacionais/normas , Insuflação/normas , Respiração Artificial/normas , Estômago/diagnóstico por imagem , Ultrassonografia de Intervenção/normas , Anestesia Geral/efeitos adversos , Anestesia Geral/métodos , Pré-Escolar , China/epidemiologia , Método Duplo-Cego , Feminino , Humanos , Insuflação/efeitos adversos , Máscaras Laríngeas/normas , Masculino , Estudos Prospectivos , Respiração Artificial/efeitos adversos , Respiração Artificial/métodos , Ultrassonografia de Intervenção/métodos
20.
Tumour Biol ; 37(10): 13751-13761, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27476171

RESUMO

MicroRNAs play an important role in tumor development and progression. Tumor growth is closely associated with glucose metabolism. Specifically, tumor cells produce energy (ATP) under aerobic and anaerobic conditions through glycolysis and metabolites, such as lactic acid and ATP, as a result of the Warburg effect. However, the transport of glucose into cells depends on protein transporters in the cell membrane. Therefore, this area has recently become a topic of interest for research on targeted cancer therapy. We found that miRNA-451 inhibits the phosphatidylinositol-3 kinase (PI3K)/Akt signaling pathway to modify the biological behavior of glioma cells. Inhibiting the PI3K/Akt pathway may prevent glucose-addicted cancer cells from performing glycolysis. Akt directly affects glycolysis by regulating the localization of the glucose transporter 1 (GLUT1). However, how miRNA-451 regulates glucose transporters on the cell membrane and affects the regulatory mechanisms of glucose metabolism in glioma cells remains unclear. Consequently, we predict and verify related gene protein interactions. By targeting CAB 39, miRNA-451 likely triggers the LKB1/AMPK/PI3K/AKT pathway, which regulates GLUT1, to inhibit the glucose metabolism of, reduce the energy supply to, and inhibit the proliferation and invasion of glioma cells. Our results suggest a new direction for the treatment of glioma.


Assuntos
Movimento Celular , Proliferação de Células , Glioma/patologia , Transportador de Glucose Tipo 1/metabolismo , MicroRNAs/genética , Animais , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Imunofluorescência , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/metabolismo , Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Glicólise , Humanos , Técnicas Imunoenzimáticas , Ácido Láctico/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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