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1.
J Hazard Mater ; 470: 134117, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38554519

RESUMO

The harmful algal blooms (HABs) can damage the ecological equilibrium of aquatic ecosystems and threaten human health. The bio-degradation of algal by algicidal bacteria is an environmentally friendly and economical approach to control HABs. This study applied an aerobic denitrification synchronization algicidal strain Streptomyces sp. LJH-12-1 (L1) to control HABs. The cell-free filtrate of the strain L1 showed a great algolytic effect on bloom-forming cyanobacterium, Microcystis aeruginosa (M. aeruginosa). The optimal algicidal property of strain L1 was indirect light-dependent algicidal with an algicidal rate of 85.0%. The functional metabolism, light-trapping, light-transfer efficiency, the content of pigments, and inhibition of photosynthesis of M. aeruginosa decreased after the addition of the supernatant of the strain L1 due to oxidative stress. Moreover, 96.05% nitrate removal rate synchronized with algicidal activity was achieved with the strain L1. The relative abundance of N cycling functional genes significantly increased during the strain L1 effect on M. aeruginosa. The algicidal efficiency of the strain L1 in the raw water was 76.70% with nitrate removal efficiency of 81.4%. Overall, this study provides a novel route to apply bacterial strain with the property of denitrification coupled with algicidal activity in treating micro-polluted water bodies.


Assuntos
Desnitrificação , Proliferação Nociva de Algas , Microcystis , Microcystis/metabolismo , Nitrogênio/metabolismo , Streptomyces/metabolismo , Nitratos/metabolismo , Fotossíntese
2.
Mikrochim Acta ; 191(3): 165, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38416241

RESUMO

A label-free immunoassay based on rolling circle amplification (RCA) and G-quadruplex/Thioflavin T (G4/ThT) is proposed to realize the sensitive detection of carboxy-terminal cross-linked fragment of type I collagen (CTX I) for bone loss. Under the optimal conditions, as low as 38.02 pg/mL of CTX I can be detected. To improve the detecting throughput and simplify the operation, a microfluidic chip was designed, fabricated, and used for CTX I detection based on the proposed assay. The detection can be completed with only a single on-chip magnetic separation step, which was easy to operate, less time-consuming, and has only low reagent consumption. The limit of detection was 131.83 pg/mL by observing with fluorescence microscope. With further improvement of detection equipment, the sensitivity of on-chip detection can be improved. It can be expected that the proposed RCA/G4/ThT immunoassay for sensitive and high-throughput automated detection of CTX I might be chosen as a potential analytical tool for clinical osteoporosis diagnosis and in-orbit bone loss detection.


Assuntos
Quadruplex G , Microfluídica , Benzotiazóis , Bioensaio
3.
Med Phys ; 51(2): 1405-1414, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37449537

RESUMO

BACKGROUND: Quality assurance of deformable image registration (DIR) is challenging because the ground truth is often unavailable. In addition, current approaches that rely on artificial transformations do not adequately resemble clinical scenarios encountered in adaptive radiotherapy. PURPOSE: We developed an atlas-based method to create a variety of patient-specific serial digital phantoms with CBCT-like image quality to assess the DIR performance for longitudinal CBCT imaging data in adaptive lung radiotherapy. METHODS: A library of deformations was created by extracting the longitudinal changes observed between a planning CT and weekly CBCT from an atlas of lung radiotherapy patients. The planning CT of an inquiry patient was first deformed by mapping the deformation pattern from a matched atlas patient, and subsequently appended with CBCT artifacts to imitate a weekly CBCT. Finally, a group of digital phantoms around an inquiry patient was produced to simulate a series of possible evolutions of tumor and adjacent normal structures. We validated the generated deformation vector fields (DVFs) to ensure numerically and physiologically realistic transformations. The proposed framework was applied to evaluate the performance of the DIR algorithm implemented in the commercial Eclipse treatment planning system in a retrospective study of eight inquiry patients. RESULTS: The generated DVFs were inverse consistent within less than 3 mm and did not exhibit unrealistic folding. The deformation patterns adequately mimicked the observed longitudinal anatomical changes of the matched atlas patients. Worse Eclipse DVF accuracy was observed in regions of low image contrast or artifacts. The structure volumes exhibiting a DVF error magnitude of equal or more than 2 mm ranged from 24.5% (spinal cord) to 69.2% (heart) and the maximum DVF error exceeded 5 mm for all structures except the spinal cord. Contour-based evaluations showed a high degree of alignment with dice similarity coefficients above 0.8 in all cases, which underestimated the overall DVF accuracy within the structures. CONCLUSIONS: It is feasible to create and augment digital phantoms based on a particular patient of interest using multiple series of deformation patterns from matched patients in an atlas. This can provide a semi-automated procedure to complement the quality assurance of CT-CBCT DIR and facilitate the clinical implementation of image-guided and adaptive radiotherapy that involve longitudinal CBCT imaging studies.


Assuntos
Tomografia Computadorizada de Feixe Cônico Espiral , Humanos , Estudos Retrospectivos , Tomografia Computadorizada de Feixe Cônico/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Imagens de Fantasmas , Pulmão/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Algoritmos
4.
Environ Sci Technol ; 58(1): 683-694, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38102081

RESUMO

The coculture theory that promotes denitrification relies on effectively utilizing the resources of low-efficiency denitrification microbes. Here, the strains Streptomyces sp. PYX97 and Streptomyces sp. TSJ96 were isolated and showed lower denitrification capacity when cultured individually. However, the coculture of strains PYX97 and TSJ96 enhanced nitrogen removal (removed 96.40% of total nitrogen) and organic carbon reduction (removed 92.13% of dissolved organic carbon) under aerobic conditions. Nitrogen balance analysis indicated that coculturing enhanced the efficiency of nitrate converted into gaseous nitrogen reaching 70.42%. Meanwhile, the coculturing promoted the cell metabolism capacity and carbon source metabolic activity. The coculture strains PYX97 and TSJ96 thrived in conditions of C/N = 10, alkalescence, and 150 rpm shaking speed. The coculturing reduced total nitrogen and CODMn in the raw water treatment by 83.32 and 84.21%, respectively. During this treatment, the cell metabolic activity and cell density increased in the coculture strains PYX97 and TSJ96 reactor. Moreover, the coculture strains could utilize aromatic protein and soluble microbial products during aerobic denitrification processes in raw water treatment. This study suggests that coculturing inefficient actinomycete strains could be a promising approach for treating polluted water bodies.


Assuntos
Actinobacteria , Desnitrificação , Aerobiose , Actinobacteria/metabolismo , Actinomyces/metabolismo , Carbono , Técnicas de Cocultura , Nitratos/metabolismo , Nitrogênio , Nitrificação
5.
J Appl Clin Med Phys ; 25(1): e14216, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38115768

RESUMO

To investigate automation of the preparation of the region of interest (ROI) for surface-guided radiotherapy (SGRT) of the whole breast with two algorithms based on contour anatomies: using the body contour, and using the breast contour. The patient dataset used for modeling consisted of 39 breast cancer patients previously treated with SGRT. The patient's anatomical structures (body and ipsilateral breast) were retrieved from the planning system, and the clinical ROI (cROI) drawn by the planners was retrieved from the SGRT system for comparison. For the body-contour-based algorithm, a convolutional neural network (MobileNet-v2) was utilized to train a synthetic human model dataset to predict body joint locations. With the body joint location knowledge, an automated ROI (aROIbody ) can be created based on: (1) the superior-inferior (S-I) borders defined by the joint locations, (2) the left-right (L-R) borders defined with 3/4 of chest width, and (3) a curation of the ROI to avoid the ipsilateral armpit. For the breast-contour-based algorithm, an aROIbreast was created by first defining the ROI in the S-I direction with the ipsilateral breast boundaries. Other steps are the same as with the body-contour-based algorithm. Among the 39 patients, 24 patients were used to fine-tune the algorithm parameters, and the remaining 15 patients were used to evaluate the quality of the aROIs against the cROIs. A blinded evaluation was performed by three SGRT expert physicists to rate the acceptability and the quality (1-10 scale) of the aROIs and cROIs, and the dice similarity coefficient (DSC) was also calculated to compare the similarity between the aROIs and cROIs. The results showed that the average acceptability was 14/15 (range: 13/15-15/15) for cROIs, 13.3/15 (range: 13/15-14/15) for aROIbody , and 14.6/15 (range: 14/15-15/15) for aROIbreast . The average quality was 7.4 ± 0.8 for cROIs, 8.1 ± 1.2 for aROIbody , and 8.2 ± 0.9 for aROIbreast . The DSC with cROIs was 0.81 ± 0.06 for aROIbody , and 0.83 ± 0.04 for aROIbreast . The ROI creation time was ∼120 s for clinical, 1.3 s for aROIbody , and 1.2 s for aROIbreast . The proposed automated algorithms can improve the ROI compliance with the SGRT protocol, with a shortened preparation time. It is ready to be integrated into the clinical workflow for automated ROI preparation.


Assuntos
Neoplasias da Mama , Radioterapia Guiada por Imagem , Humanos , Feminino , Neoplasias da Mama/radioterapia , Algoritmos , Mama/diagnóstico por imagem , Redes Neurais de Computação , Planejamento da Radioterapia Assistida por Computador/métodos
6.
Anal Methods ; 15(21): 2641-2649, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37203352

RESUMO

Rapid detection of nucleic acids is integral for clinical diagnostics, especially if a major public-health emergency occurs. However, such detection cannot be carried out efficiently in remote areas limited by medical resources. Herein, a dual-labeled fluorescence resonance energy transfer (FRET) lateral flow assay (LFA) based on one-pot enzyme-free cascade amplification was developed for rapid, convenient, and sensitive detection of open reading frame (ORF)1ab of severe acute respiratory syndrome-coronavirus-2. The catalyzed hairpin assembly (CHA) reaction of two well-designed hairpin probes was initiated by a target sequence and generated a hybridization chain reaction (HCR) initiator. Then, HCR probes modified with biotin were initiated to produce long DNA nanowires. After two-level amplification, the cascade-amplified product was detected by dual-labeled lateral flow strips. Gold nanoparticles (AuNPs)-streptavidin combined with the product and then ran along a nitrocellulose membrane under the action of capillary force. After binding with fluorescent microsphere-labeled-specific probes on the T line, a positive signal (red color) could be observed. Meanwhile, AuNPs could quench the fluorescence of the T line, and an inverse relationship between fluorescence intensity and the concentration of the CHA-HCR-amplified product was formed. The proposed strategy achieved a satisfactory limit of detection of 2.46 pM for colorimetric detection and 174 fM for fluorescent detection, respectively. Benefitting from the features of being one-pot, enzyme-free, low background, high sensitivity, and selectivity, this strategy shows great potential in bioanalysis and clinical diagnostics upon further development.


Assuntos
COVID-19 , Nanopartículas Metálicas , Humanos , Ouro , COVID-19/diagnóstico , DNA/análise , Hibridização de Ácido Nucleico
7.
Sci Total Environ ; 884: 163859, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37142031

RESUMO

Despite the growing interest in using mixed-culture aerobic denitrifying fungal flora (mixed-CADFF) for water remediation, there is limited research on their nitrogen removal performance in low C/N polluted water bodies. To address this knowledge gap, we isolated three mixed-CADFFs from overlying water in urban lakes to evaluate their removal performance. The total nitrogen (TN) removal efficiencies were 93.60 %, 94.64 %, and 95.18 %, while the dissolved organic carbon removal efficiencies were 96.64 %, 95.12 %, and 96.70 % for mixed-CADFF LN3, LN7, and LN15, respectively in the denitrification medium under aerobic conditions at 48 h cultivation. The three mixed-CADFFs could utilize diverse types of low molecular weight carbon sources to drive the aerobic denitrification processes efficiently. The optimal C/N ratio for the mixed-CADFFs were C/N = 10, and then C/N = 15, 7, 5, and 2. The high-throughput sequencing analysis of three mixed-CADFFs indicated that Eurotiomycetes, Cystobasidiomycetes, and Sordariomycetes were the dominant class in the communities at class level. The network analysis showed that the rare fungal species, such as Scedosporium dehoogii Saitozyma, and Candida intermedia presented positively co-occurred with the TN removal and organic matter reduction capacity. Immobilization mixed-CADFFs treatment raw water experiments indicated that three mixed-CADFFs could reduce nearly 62.73 % of TN in the low C/N micro-polluted raw water treatment. Moreover, the cell density and cell metabolism indexes were also increased during the raw water treatment. This study will provides new insight into resource utilization of the mixed-culture aerobic denitrifying fungal community in field of environment restoration.


Assuntos
Desnitrificação , Micobioma , Aerobiose , Nitrogênio/metabolismo , Carbono , Nitratos
8.
IEEE Trans Vis Comput Graph ; 29(1): 193-202, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36166554

RESUMO

We present SizePairs, a new technique to create stable and balanced treemap layouts that visualize values changing over time in hierarchical data. To achieve an overall high-quality result across all time steps in terms of stability and aspect ratio, SizePairs employs a new hierarchical size-based pairing algorithm that recursively pairs two nodes that complement their size changes over time and have similar sizes. SizePairs maximizes the visual quality and stability by optimizing the splitting orientation of each internal node and flipping leaf nodes, if necessary. We also present a comprehensive comparison of SizePairs against the state-of-the-art treemaps developed for visualizing time-dependent data. SizePairs outperforms existing techniques in both visual quality and stability, while being faster than the local moves technique.

9.
Front Oncol ; 12: 747825, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35359395

RESUMO

Purpose: Commercial independent monitor unit (IMU) check systems for high-magnetic-field MR-guided radiation therapy (RT) systems are lacking. We investigated the feasibility of adopting an existing treatment planning system (TPS) as an IMU check for online adaptive radiotherapy using 1.5-Tesla MR-Linac. Methods: The 7-MV flattening filter free (FFF) beam and multi-leaf collimator (MLC) models of a 1.5-T Elekta Unity MR-Linac within Monte Carlo-based Monaco TPS were used to generate an optimized beam model in Eclipse TPS. The MLC dosimetric leaf gap of the beam in Eclipse was determined by matching the dose distribution of Eclipse-generated intensity-modulated radiation therapy (IMRT) plans using the Analytical Anisotropic Algorithm (AAA) algorithm to Monaco plans. The plans were automatically adjusted for different source-to-axis distances (SADs) between the two systems. For IMU check, the treatment plans developed in Monaco were transferred to Eclipse to recalculate the dose using AAA. A plug-in within Eclipse was created to perform a 2D gamma analysis of the AAA and Monte Carlo dose distribution on a beam's eye view parallel plane. Monaco dose distribution was shifted laterally by 2 mm during gamma analysis to account for the impact of magnetic field on electron trajectories. Eclipse doses for posterior beams were corrected for both the Unity couch and the posterior MR coil attenuation. Thirteen patients, each with 4-5 fractions for a variety of tumor sites (pancreas, rectum, and prostate), were tested. Results: After thorough commissioning, the method was implemented as part of the standard clinical workflow. A total of 62 online plans, each with approximately 15 beams, were evaluated. The average per-beam gamma (3%/3 mm) pass rate for plans was 97.9% (range, 95.9% to 98.8%). The average pass rate per beam for all 932 beams used in these plans was 97.9% ± 1.9%, with the lowest per-beam gamma pass rate at 88.4%. The time for the process was within 3.2 ± 0.9 min. Conclusion: The use of a second planning system provides an efficient way to perform IMU checks with clinically acceptable accuracy for online adaptive plans on Unity MR-Linac. This is essential for meeting the safety requirements for second checks as outlined in American Association of Physicists in Medicine Task Group (AAPM TG) reports 114 and 219.

10.
Front Immunol ; 13: 791799, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401532

RESUMO

Yersinia pestis, the cause of plague, is a newly evolved Gram-negative bacterium. Through the acquisition of the plasminogen activator (Pla), Y. pestis gained the means to rapidly disseminate throughout its mammalian hosts. It was suggested that Y. pestis utilizes Pla to interact with the DEC-205 (CD205) receptor on antigen-presenting cells (APCs) to initiate host dissemination and infection. However, the evolutionary origin of Pla has not been fully elucidated. The PgtE enzyme of Salmonella enterica, involved in host dissemination, shows sequence similarity with the Y. pestis Pla. In this study, we demonstrated that both Escherichia coli K-12 and Y. pestis bacteria expressing the PgtE-protein were able to interact with primary alveolar macrophages and DEC-205-transfected CHO cells. The interaction between PgtE-expressing bacteria and DEC-205-expressing transfectants could be inhibited by the application of an anti-DEC-205 antibody. Moreover, PgtE-expressing Y. pestis partially re-gained the ability to promote host dissemination and infection. In conclusion, the DEC-205-PgtE interaction plays a role in promoting the dissemination and infection of Y. pestis, suggesting that Pla and the PgtE of S. enterica might share a common evolutionary origin.


Assuntos
Escherichia coli K12 , Salmonella enterica , Yersinia pestis , Animais , Proteínas de Bactérias/genética , Cricetinae , Cricetulus , Ativadores de Plasminogênio
11.
Radiother Oncol ; 169: 57-63, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35189155

RESUMO

BACKGROUND AND PURPOSE: To develop a novel deep learning algorithm of sequential analysis, Seq2Seq, for predicting weekly anatomical changes of lung tumor and esophagus during definitive radiotherapy, incorporate the potential tumor shrinkage into a predictive treatment planning paradigm, and improve the therapeutic ratio. METHODS AND MATERIALS: Seq2Seq starts with the primary tumor and esophagus observed on the planning CT to predict their geometric evolution during radiotherapy on a weekly basis, and subsequently updates the predictions with new snapshots acquired via weekly CBCTs. Seq2Seq is equipped with convolutional long short term memory to analyze the spatial-temporal changes of longitudinal images, trained and validated using a dataset including sixty patients. Predictive plans were optimized according to each weekly prediction and made ready for weekly deployment to mitigate the clinical burden of online weekly replanning. RESULTS: Seq2Seq tracks structural changes well: DICE between predicted and actual weekly tumor and esophagus were (0.83 ± 0.10, 0.79 ± 0.14, 0.78 ± 0.12, 0.77 ± 0.12, 0.75 ± 0.12, 0.71 ± 0.17), and (0.72 ± 0.16, 0.73 ± 0.11, 0.75 ± 0.08, 0.74 ± 0.09, 0.72 ± 0.14, 0.71 ± 0.14), respectively, while the average Hausdorff distances were within 2 mm. Evaluating dose to the actual weekly tumor and esophagus, a 4.2 Gy reduction in esophagus mean dose while maintaining 60 Gy tumor coverage was achieved with the predictive weekly plans, compared to the plan optimized using the initial tumor and esophagus alone, primarily due to noticeable tumor shrinkage during radiotherapy. CONCLUSION: It is feasible to predict the longitudinal changes of tumor and esophagus with the Seq2Seq, which could lead to improving the efficiency and effectiveness of lung adaptive radiotherapy.


Assuntos
Aprendizado Profundo , Neoplasias Pulmonares , Radioterapia de Intensidade Modulada , Humanos , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos
12.
J Med Microbiol ; 70(3)2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33591245

RESUMO

Introduction. Shigella sonnei, the cause of bacillary dysentery, belongs to Gram-negative enteropathogenic bacteria. S. sonnei contains a 210 kb virulence plasmid that encodes an O-antigen gene cluster of LPSs. However, this virulence plasmid is frequently lost during replication. It is well-documented that after losing the O-antigen and becoming rough strains, the Gram-negative bacteria may express an LPS core on its surface. Previous studies have suggested that by using the LPS core, Gram-negative bacteria can interact with several C-type lectin receptors that are expressed on antigen-presenting cells (APCs).Hypothesis/Gap Statement. S. sonnei by losing the virulence plasmid may hijack APCs via the interactions of LPS-CD209/CD207.Aim. This study aimed to investigate if the S. sonnei rough strain, by losing the virulence plasmid, interacted with APCs that express C-type lectins of human CD207, human CD209a and mouse CD209b.Methodology. SDS-PAGE silver staining was used to examine the O-antigen expression of S. sonnei WT and its rough strain. Invasion assays and inhibition assays were used to examine the ability of S. sonnei WT and its rough strain to invade APCs and investigate whether CD209 and CD207 are receptors for phagocytosis of rough S. sonnei. Animal assays were used to observe the dissemination of S. sonnei.Results. S. sonnei did not express O-antigens after losing the virulence plasmid. The S. sonnei rough strain invades with APCs, including human dendritic cells (DCs) and mouse macrophages. CD209 and CD207 are receptors for phagocytosis of rough S. sonnei. Expression of the O-antigen reduces the ability of the S. sonnei rough strain to be disseminated to mesenteric lymph nodes and spleens.Conclusion. This work demonstrated that S. sonnei rough strains - by losing the virulence plasmid - invaded APCs through interactions with CD209 and CD207 receptors.


Assuntos
Antígenos CD/imunologia , Moléculas de Adesão Celular/imunologia , Disenteria Bacilar/microbiologia , Lectinas Tipo C/imunologia , Lectinas de Ligação a Manose/imunologia , Antígenos O , Plasmídeos , Receptores de Superfície Celular/imunologia , Shigella sonnei/patogenicidade , Virulência/genética , Animais , Células CHO , Cricetulus , Células Dendríticas/microbiologia , Interações Hospedeiro-Patógeno , Humanos , Macrófagos/microbiologia , Camundongos , Antígenos O/genética , Antígenos O/metabolismo , Shigella sonnei/genética
13.
Infect Immun ; 87(8)2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31085704

RESUMO

Salmonella enterica serovar Typhimurium, a Gram-negative bacterium, can cause infectious diseases ranging from gastroenteritis to systemic dissemination and infection. However, the molecular mechanisms underlying this bacterial dissemination have yet to be elucidated. A study indicated that using the lipopolysaccharide (LPS) core as a ligand, S Typhimurium was able to bind human dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (hCD209a), an HIV receptor that promotes viral dissemination by hijacking antigen-presenting cells (APCs). In this study, we showed that S Typhimurium interacted with CD209s, leading to the invasion of APCs and potentially the dissemination to regional lymph nodes, spleen, and liver in mice. Shielding of the exposed LPS core through the expression of O-antigen reduces dissemination and infection. Thus, we propose that similar to HIV, S Typhimurium may also utilize APCs via interactions with CD209s as a way to disseminate to the lymph nodes, spleen, and liver to initiate host infection.


Assuntos
Moléculas de Adesão Celular/fisiologia , Lectinas Tipo C/fisiologia , Receptores de Superfície Celular/fisiologia , Salmonella typhimurium/patogenicidade , Animais , Células Apresentadoras de Antígenos/microbiologia , Feminino , Interações Hospedeiro-Patógeno , Humanos , Lipopolissacarídeos/fisiologia , Mananas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Antígenos O/fisiologia , Nódulos Linfáticos Agregados/fisiologia , Fagocitose , Células RAW 264.7
14.
Sensors (Basel) ; 19(4)2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30781700

RESUMO

Prognostics and Health Management (PHM) is an emerging technique which can improve the availability and efficiency of equipment. A series of related optimization of the PHM system has been achieved due to the growing need for lowering the cost of maintenance. The PHM system highly relies on data collected from its components. Based on the theory of machine learning, this paper proposes a bio-inspired PHM model based on a dissolved gas-in-oil dataset (DGA) to diagnose faults of transformes in power grids. Specifically, this model applies Bat algorithm (BA), a metaheuristic population-based algorithm, to optimize the structure of the Back-propagation neural network (BPNN). Furthermore, this paper proposes a modified Bat algorithm (MBA); here the chaos strategy is utilized to improve the random initialization process of BA in order to avoid falling into local optima. To prove that the proposed PHM model has better fault diagnostic performance than others, fitness and mean squared error (MSE) of Bat-BPNN are set as reference amounts to compare with other power grid PHM approaches including BPNN, Particle swarm optimization (PSO)-BPNN, as well as Genetic algorithm (GA)-BPNN. The experimental results show that the BA-BPNN model has increased the fault diagnosis accuracy from 77.14% to 97.14%, which is higher than other power transformer PHM models.

15.
Infect Immun ; 87(1)2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30348825

RESUMO

Yersinia pseudotuberculosis is a Gram-negative enteropathogen and causes gastrointestinal infections. It disseminates from gut to mesenteric lymph nodes (MLNs), spleen, and liver of infected humans and animals. Although the molecular mechanisms for dissemination and infection are unclear, many Gram-negative enteropathogens presumably invade the small intestine via Peyer's patches to initiate dissemination. In this study, we demonstrate that Y. pseudotuberculosis utilizes its lipopolysaccharide (LPS) core to interact with CD209 receptors, leading to invasion of human dendritic cells (DCs) and murine macrophages. These Y. pseudotuberculosis-CD209 interactions result in bacterial dissemination to MLNs, spleens, and livers of both wild-type and Peyer's patch-deficient mice. The blocking of the Y. pseudotuberculosis-CD209 interactions by expression of O-antigen and with oligosaccharides reduces infectivity. Based on the well-documented studies in which HIV-CD209 interaction leads to viral dissemination, we therefore propose an infection route for Y. pseudotuberculosis where this pathogen, after penetrating the intestinal mucosal membrane, hijacks the Y. pseudotuberculosis-CD209 interaction antigen-presenting cells to reach their target destinations, MLNs, spleens, and livers.


Assuntos
Moléculas de Adesão Celular/metabolismo , Células Dendríticas/microbiologia , Endocitose , Interações Hospedeiro-Patógeno , Lectinas Tipo C/metabolismo , Lipopolissacarídeos/metabolismo , Macrófagos/microbiologia , Receptores de Superfície Celular/metabolismo , Yersinia pseudotuberculosis/patogenicidade , Animais , Aderência Bacteriana , Células Cultivadas , Modelos Animais de Doenças , Humanos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ligação Proteica , Yersiniose/microbiologia , Yersiniose/patologia , Yersiniose/fisiopatologia
16.
Sensors (Basel) ; 18(12)2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30558208

RESUMO

An emerging prognostic and health management (PHM) technology has recently attracted a great deal of attention from academies, industries, and governments. The need for higher equipment availability and lower maintenance cost is driving the development and integration of prognostic and health management systems. PHM models depend on the smart sensors and data generated from sensors. This paper proposed a machine learning-based methods for developing PHM models from sensor data to perform fault diagnostic for transformer systems in a smart grid. In particular, we apply the Cuckoo Search (CS) algorithm to optimize the Back-propagation (BP) neural network in order to build high performance fault diagnostics models. The models were developed using sensor data called dissolved gas data in oil of the power transformer. We validated the models using real sensor data collected from power transformers in China. The results demonstrate that the developed meta heuristic algorithm for optimizing the parameters of the neural network is effective and useful; and machine learning-based models significantly improved the performance and accuracy of fault diagnosis/detection for power transformer PHM.

17.
Sci Rep ; 7(1): 2206, 2017 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-28526886

RESUMO

FK866 exhibits a protective effect on D-galactosamine (GaIN)/lipopolysaccharide (LPS) and concanavalin A (ConA)-induced acute liver failure (ALF), but the mechanism by which FK866 affords this benefit has not yet been elucidated. Autophagy has a protective effect on acute liver injury. However, the contribution of autophagy to FK866-conferred hepatoprotection is still unclear. This study aimed to investigate whether FK866 could attenuate GaIN/LPS and ConA-induced ALF through c-jun-N-terminal kinase (JNK)-dependent autophagy. In vivo, Mice were pretreated with FK866 at 24, 12, and 0.5 h before treatment with GaIN/LPS and ConA. 3-methyladenine (3MA) or rapamycin were used to determine the role of autophagy in FK866-conferred hepatoprotection. In primary hepatocytes, autophagy was inhibited by 3MA or autophagy-related protein 7 (Atg7) small interfering RNA (siRNA). JNK was suppressed by SP600125 or Jnk siRNA. FK866 alleviated hepatotoxicity and increased autophagy while decreased JNK activation. Suppression of autophagy abolished the FK866-conferred protection. Inhibition of JNK increased autophagy and exhibited strongly protective effect. Collectively, FK866 could ameliorate GaIN/LPS and ConA-induced ALF through induction of autophagy while suppression of JNK. These findings suggest that FK866 acts as a simple and applicable preconditioning intervention to protect against ALF; autophagy and JNK may also provide therapeutic targets for ALF treatment.


Assuntos
Acrilamidas/farmacologia , Autofagia/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Falência Hepática Aguda/metabolismo , Piperidinas/farmacologia , Animais , Proteína 7 Relacionada à Autofagia/genética , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Hepatócitos/metabolismo , Hepatócitos/patologia , Lipopolissacarídeos/efeitos adversos , Falência Hepática Aguda/tratamento farmacológico , Falência Hepática Aguda/etiologia , Falência Hepática Aguda/patologia , Testes de Função Hepática , Camundongos , Substâncias Protetoras/farmacologia , Transdução de Sinais/efeitos dos fármacos
18.
Obesity (Silver Spring) ; 25(3): 561-571, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28145056

RESUMO

OBJECTIVE: 1,25(OH)2 D3 has been reported to attenuate liver steatosis; however, its exact mechanism of action remains poorly understood. This study aimed to determine whether 1,25(OH)2 D3 can attenuate hepatic steatosis by inducing autophagy. METHODS: Male C57BL/6 mice fed a high-fat diet (HFD) were injected with 1,25(OH)2 D3 for 4 weeks. These mice were given 3-methyladenine (3-MA) to inhibit autophagy. HepG2 cells were preincubated with a free fatty acid (FFA) and then treated with 1,25(OH)2 D3 . Vitamin D receptor (VDR) shRNA and autophagy-related 16-like 1 (ATG16L1) siRNA were used for VDR knockdown or ATG16L1 silencing, respectively. RESULTS: 1,25(OH)2 D3 diminished HFD-induced liver damage and steatosis, changes accompanied by autophagy and ATG16L1 expression upregulation. Inhibition of 1,25(OH)2 D3 -induced autophagy mediated by 3-MA blocked the protective effects of 1,25(OH)2 D3 on hepatic steatosis. Additionally, 1,25(OH)2 D3 -induced autophagy appeared to play a role in anti-inflammation and lipid metabolism modulation in the liver. In HepG2 cells, 1,25(OH)2 D3 reduced lipid accumulation and increased autophagy and ATG16L1 expression; however, this effect was abrogated after VDR knockdown. The protective effects of 1,25(OH)2 D3 -mediated autophagy against lipid accumulation were abolished by 3-MA. Furthermore, siRNA-mediated ATG16L1 knockdown prevented 1,25(OH)2 D3 -induced autophagy, resulting in increased fat accumulation. CONCLUSIONS: The data suggest that 1,25(OH)2 D3 may ameliorate hepatic steatosis by inducing autophagy by upregulating ATG16L1.


Assuntos
Autofagia/efeitos dos fármacos , Calcitriol/farmacologia , Ácidos Graxos não Esterificados/farmacologia , Fígado Gorduroso/tratamento farmacológico , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Proteínas Relacionadas à Autofagia , Calcitriol/uso terapêutico , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Dieta Hiperlipídica , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Inativação Gênica , Células Hep G2 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Interferente Pequeno , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Regulação para Cima
19.
Sci Rep ; 6: 25042, 2016 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-27150843

RESUMO

We previously demonstrated that baicalein could protect against liver ischemia/reperfusion (I/R) injury in mice. The exact mechanism of baicalein remains poorly understood. Autophagy plays an important role in protecting against I/R injury. This study was designed to determine whether baicalein could protect against liver I/R injury via induction of autophagy in rats. Baicalein was intraperitoneally injected 1 h before warm ischemia. Pretreatment with baicalein prior to I/R insult significantly blunted I/R-induced elevations of serum aminotransferase levels and significantly improved the histological status of livers. Electron microscopy and expression of the autophagic marker LC3B-II suggested induction of autophagy after baicalein treatment. Moreover, inhibition of the baicalein-induced autophagy using 3-methyladenine (3-MA) worsened liver injury. Furthermore, baicalein treatment increased heme oxygenase (HO)-1 expression, and pharmacological inhibition of HO-1 with tin protoporphyrin IX (SnPP) abolished the baicalein-mediated autophagy and the hepatocellular protection. In primary rat hepatocytes, baicalein-induced autophagy also protected hepatocytes from hypoxia/reoxygenation injury in vitro and the beneficial effect was abrogated by 3-MA or Atg7 siRNA, respectively. Suppression of HO-1 activity by SnPP or HO-1 siRNA prevented the baicalein-mediated autophagy and resulted in increased hepatocellular injury. Collectively, these results suggest that baicalein prevents hepatocellular injury via induction of HO-1-mediated autophagy.


Assuntos
Autofagia , Flavanonas/metabolismo , Fígado/patologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Modelos Animais de Doenças , Histocitoquímica , Camundongos , Microscopia Eletrônica , Proteínas Associadas aos Microtúbulos/análise , Ratos , Transaminases/sangue
20.
Sheng Li Xue Bao ; 68(1): 57-64, 2016 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-26915323

RESUMO

Gab proteins, Grb2 (growth factor receptor binding protein 2)-associated binder, are important scaffolding adapter proteins required by many signaling pathways. In mammals, the Gab proteins mainly consist of Gab1, Gab2 and Gab3, and are involved in the amplification and integration of signal transduction evoked by a variety of extracellular stimuli, including various growth factors and cytokines. They are known to play key roles in many biological processes through the two classical signal pathways, SHP2/RAS/ERK and PI3K/AKT. In this review, we provide an overview of the structure and function of the scaffolding adapter, Gab, with a special focus on its role in tumor, inflammation and cardiovascular diseases.


Assuntos
Doenças Cardiovasculares , Inflamação , Neoplasias , Proteínas Adaptadoras de Transdução de Sinal , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Fosfatidilinositol 3-Quinases , Fosforilação , Transdução de Sinais
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