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1.
IEEE Trans Vis Comput Graph ; 30(5): 2347-2356, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38437096

RESUMO

Projector video compensation aims to cancel the geometric and photometric distortions caused by non-ideal projection surfaces and environments when projecting videos. Most existing projector compensation methods start by projecting and capturing a set of sampling images, followed by an offline compensation model training step. Thus, abundant user effort is required before the users can watch the video. Moreover, the sampling images have little prior knowledge of the video content and may lead to suboptimal results. To address these issues, this paper builds a video compensation system that can online adapt the compensation parameters. Our approach consists of five threads and can perform compensation, projection, capturing, and short-term and long-term model updates in parallel. Due to the parallel mechanism, rather than projecting and capturing hundreds of sampling images and training the model offline, we can directly use the projected and captured video frames for model updates on the fly. To quickly apply to the new environment, we introduce a deep learning-based compensation model that integrates a fixed transformer-based method and a novel CNN-based network. Moreover, for fast convergence and to reduce error accumulation during fine-tuning, we present a strategy that cooperates with short-term and long-term memory model updates. Experiments show that it significantly outperforms state-of-the-art baselines.

2.
Heliyon ; 10(4): e25495, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38384563

RESUMO

Introduction: Knee osteoarthritis (KOA) is a type of joint disease causing degenerative changes that are challenging to treat. The improved tug-of-war acupuncture (BHZF) can improve joint pain in KOA. However, the associated mechanism has not been validated. Methods: The KOA rabbit model was established. After the surgery, the improved BHZF was provided as an intervention, and the animals were euthanized after 2 weeks. Histopathological changes in the synovium and cartilage were observed on hematoxylin & eosin staining and Safranin O-Fast Green staining. Synovial fluid and serum samples were collected to assess the presence of cytokines using the enzyme-linked immunosorbent assay. The expression of M1 macrophage (CD86) and M2 macrophage (ARG1) markers in the cartilage and synovium was detected via immunohistochemistry and immunofluorescence assays. Results: The improved BHZF could reduce KOA-related pain and inhibit joint swelling. Further, it significantly maintained the morphology of articular chondrocytes in KOA and reduced the decomposition of the cartilage matrix. Then, it significantly reduced the expression of CD86-positive cells (P < 0.05), and increased the expression of ARG1-positive cells in the cartilage and synovium (P < 0.05). Moreover, it significantly decreased the expression of inflammatory factors interleukin (IL)-1 beta and tumor necrosis factor-alpha in the serum and synovial fluid (P < 0.05), and significantly increased the expression levels of anti-inflammatory cytokines IL-4 and IL-10 (P < 0.05). Conclusions: The improved BHZF can relieve pain and improve cartilage damage by regulating macrophage polarization in KOA.

3.
J Back Musculoskelet Rehabil ; 37(3): 617-628, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38277281

RESUMO

BACKGROUND: Chronic lower back pain (CLBP) is one of the most common disorders worldwide. Flash cupping has the ability to relieve CLBP; nevertheless, its impact on CLBP and the likely mechanism of action have not been studied. OBJECTIVE: The goal of this study was to assess the impact of a single, brief cupping session on CLBP and low back muscle activity using multichannel surface electromyography (sEMG). METHODS: In this randomized controlled trial, 24 patients with CLBP were enrolled and randomly assigned to the control group (treated by acupuncture) and cupping group (treated by acupuncture and flash cupping). Acupuncture was applied on the shen shu (BL23), dachang shu (BL25), and wei zhong (BL40) acupoints in both the groups. A brief cupping treatment was applied to the shen shu (BL23), qihai shu (BL24), dachang shu (BL25), guanyuan shu (BL26), and xiaochang shu (BL27) acupoints on both sides of the lower back in the cupping group. The numeric rating scale (NRS) was used to assess therapy efficacy for lower back pain (LBP) before and after treatment. Surface EMG data collected during symmetrical trunk flexion-extension movements were utilized to measure lower back muscle activity and the effectiveness of LBP therapy. RESULTS: There was no statistically significant difference (P= 0.63) in pain intensity between the two groups before and after treatment. There was a statistically significant difference (P= 0.04) between the control group and the cupping group in the sEMG topographic map parameter CoGx-To-Midline. CONCLUSION: This study established a connection between the action mechanism of flash cupping and enhanced horizontal synchronization of lower back muscular activity.


Assuntos
Terapia por Acupuntura , Dor Crônica , Ventosaterapia , Eletromiografia , Dor Lombar , Humanos , Dor Lombar/terapia , Dor Lombar/fisiopatologia , Dor Lombar/reabilitação , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Ventosaterapia/métodos , Dor Crônica/terapia , Dor Crônica/fisiopatologia , Terapia por Acupuntura/métodos , Resultado do Tratamento , Medição da Dor , Pontos de Acupuntura
4.
Microb Cell Fact ; 21(1): 147, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35854349

RESUMO

BACKGROUND: Macrolactins, a type of macrolide antibiotic, are toxic to the producer strains. As such, its level is usually maintained below the lethal concentration during the fermentation process. To improve the production of macrolactins, we applied adaptive laboratory evolution technology to engineer a saline-resistant mutant strain. The hypothesis that strains with saline resistance show improved macrolactins production was investigated. RESULTS: Using saline stress as a selective pressure, we engineered a mutant strain with saline resistance coupled with enhanced macrolactins production within 60 days using a self-made device. As compared with the parental strain, the evolved strain produced macrolactins with 11.93% improvement in non-saline stress fermentation medium containing 50 g/L glucose, when the glucose concentration increased to 70 g/L, the evolved strain produced macrolactins with 71.04% improvement. RNA sequencing and metabolomics results revealed that amino acid metabolism was involved in the production of macrolactins in the evolved strain. Furthermore, genome sequencing of the evolved strain revealed a candidate mutation, hisDD41Y, that was causal for the improved MLNs production, it was 3.42 times higher than the control in the overexpression hisDD41Y strain. Results revealed that saline resistance protected the producer strain from feedback inhibition of end-product (macrolide antibiotic), resulting in enhanced MLNs production. CONCLUSIONS: In the present work, we successfully engineered a mutant strain with enhanced macrolactins production by adaptive laboratory evolution using saline stress as a selective pressure. Based on physiological, transcriptomic and genetic analysis, amino acid metabolism was found to benefit macrolactins production improvement. Our strategy might be applicable to improve the production of other kinds of macrolide antibiotics and other toxic compounds. The identification of the hisD mutation will allow for the deduction of metabolic engineering strategies in future research.


Assuntos
Bacillus , Aminoácidos/genética , Antibacterianos , Bacillus/genética , Fermentação , Macrolídeos , Engenharia Metabólica/métodos
5.
Comput Biol Chem ; 99: 107712, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35689994

RESUMO

Kinases have become an important class of targets for drug discovery since the milestone approval of imatinib in 2001. Although a great success has been achieved for targeting kinases with over 70 inhibitors approved by the FDA, it is inevitable that drug resistance would emerge during treatment. Thus, assessment of the kinase mutations is an essential issue for the development of the next generation inhibitors. Apoptosis signal-regulating kinase 1 (ASK1) is a crucial regulator of classical mitogen-activated protein kinase cascade that is being explored under several clinical trials as a promising target. Herein, we investigate the catalytic activity in vitro of ASK1 by constructing two mutants: M754T and H729L, from gatekeeper and αC-helix, respectively. Compared to wild type, the mutation of M754T and H729L results in a roughly 3-fold and 2-fold decrease in binding affinity experimentally. In addition, their binding modes with substrate are theoretically predicted and compared by molecular dynamics. Trajectory analyses of simulations indicate that the decrease of binding affinity should be attributed to the loss of H-bond interaction with gatekeeper methionine. Unexpectedly, the conformation of αC-helix in H729L mutant did not alter significantly during the simulations, although the putatively important H-bond with H729 is lost. These simulations showed the regulatory role of H729 in αC-helix is maintained by leucine residue through the interaction with non-polar residues around H729 site.


Assuntos
MAP Quinase Quinase Quinase 5 , Inibidores de Proteínas Quinases , Humanos , MAP Quinase Quinase Quinase 5/genética , Simulação de Dinâmica Molecular , Mutação , Inibidores de Proteínas Quinases/química
6.
Front Microbiol ; 13: 930981, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35722281

RESUMO

The Beibu Gulf harbors abundant underexplored marine microbial resources, which are rich in diversified secondary metabolites. The genera Vibrio is a well-known pathogenic bacterium of aquatic animals. In this study, 22 fungal strains were isolated and identified from the Beibu Gulf coral via the serial dilution method and internal transcribed spacer (ITS) sequence analysis, which were further divided into three branches by phylogenetic tree analysis. The crude extracts of them via small-scale fermentation were selected for the screening of inhibitory activity against Vibrio alginalyticus, Vibrio coralliilyticus, Vibrio harveyi, Vibrio parahaemolyticus, Vibrio owensii, and Vibrio shilonii. The results showed that eight fungal extracts displayed anti-Vibrio activity via the filter paper disk assay. Several of them showed strong inhibitory effects. Then, two tetramic acid alkaloids, equisetin (1) and 5'-epiequisetin (2), were identified from Fusarium equiseti BBG10 by bioassay-guided isolation, both of which inhibited the growth of Vibrio spp. with the MIC values of 86-132 µg/ml. The scanning electron microscope results showed that cell membranes of Vibrio became corrugated, distorted or ruptured after treatment with 1 and 2. Taken together, this study provided eight fungal isolates with anti-Vibrio potentials, and two alkaloid-type antibiotics were found with anti-Vibrio effects from the bioactive strain F. equiseti BBG10. Our findings highlight the importance of exploring promising microbes from the Beibu Gulf for the identification of anti-Vibrio for future antibiotic development.

7.
PLoS One ; 17(5): e0267138, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35512010

RESUMO

Student Dropout Prediction (SDP) is pivotal in mitigating withdrawals in Massive Open Online Courses. Previous studies generally modeled the SDP problem as a binary classification task, providing a single prediction outcome. Accordingly, some attempts introduce survival analysis methods to achieve continuous and consistent predictions over time. However, the volatility and sparsity of data always weaken the models' performance. Prevailing solutions rely heavily on data pre-processing independent of predictive models, which are labor-intensive and may contaminate authentic data. This paper proposes a Survival Analysis based Volatility and Sparsity Modeling Network (SAVSNet) to address these issues in an end-to-end deep learning framework. Specifically, SAVSNet smooths the volatile time series by convolution network while preserving the original data information using Long-Short Term Memory Network (LSTM). Furthermore, we propose a Time-Missing-Aware LSTM unit to mitigate the impact of data sparsity by integrating informative missingness patterns into the model. A survival analysis loss function is adopted for parameter estimation, and the model outputs monotonically decreasing survival probabilities. In the experiments, we compare the proposed method with state-of-the-art methods in two real-world MOOC datasets, and the experiment results show the effectiveness of our proposed model.


Assuntos
Redes Neurais de Computação , Evasão Escolar , Humanos , Memória de Longo Prazo , Análise de Sobrevida
8.
Mar Drugs ; 20(4)2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35447933

RESUMO

Phycocyanin (PC) is a pigment-protein complex. It has been reported that PC exerts anti-colorectal cancer activities, although the underlying mechanism has not been fully elucidated. In the present study, azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced mice were orally administrated with PC, followed by microbiota and transcriptomic analyses to investigate the effects of PC on colitis-associated cancer (CAC). Our results indicated that PC ameliorated AOM/DSS induced inflammation. PC treatment significantly reduced the number of colorectal tumors and inhibited proliferation of epithelial cell in CAC mice. Moreover, PC reduced the relative abundance of Firmicutes, Deferribacteres, Proteobacteria and Epsilonbacteraeota at phylum level. Transcriptomic analysis showed that the expression of genes involved in the intestinal barrier were altered upon PC administration, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed the IL-17 signaling pathway was affected by PC treatment. The study demonstrated the protective therapeutic action of PC on CAC.


Assuntos
Neoplasias Associadas a Colite , Colite , Neoplasias Colorretais , Microbioma Gastrointestinal , Animais , Azoximetano/toxicidade , Colite/induzido quimicamente , Colite/complicações , Colite/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Interleucina-17 , Camundongos , Camundongos Endogâmicos C57BL , Ficocianina/metabolismo , Ficocianina/farmacologia , Ficocianina/uso terapêutico , Transdução de Sinais
9.
Mar Drugs ; 20(3)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35323477

RESUMO

One new depsidone derivative, aspergillusidone H (3), along with seven known biosynthetically related chlorinated polyketides, were obtained from the Beibu Gulf coral-derived fungus Aspergillus unguis GXIMD 02505. Their structures were determined by comprehensive physicochemical and spectroscopic data interpretation. Notably, the X-ray crystal structure of 2 and the previously unknown absolute configuration of 8, assigned by ECD calculations, are described here for the first time. Compounds 1-5, 7 and 8 exhibited inhibition of lipopolysaccharide (LPS)-induced NF-κB in RAW 264.7 macrophages at 20 µM. In addition, the two potent inhibitors (2 and 7) dose-dependently suppressed RANKL-induced osteoclast differentiation without any evidence of cytotoxicity in bone marrow macrophages cells (BMMs). This is the first report of osteoclastogenesis inhibitory activity for the metabolites of these kinds. Besides, compounds 1, 2, 4, and 6-8 showed inhibitory activity against marine biofilm-forming bacteria, methicillin-resistant Staphylococcus aureus, Microbulbifer variabilis, Marinobacterium jannaschii, and Vibrio pelagius, with their MIC values ranging from 2 to 64 µg/mL. These findings provide a basis for further development of chlorinated polyketides as potential inhibitors of osteoclast differentiation and/or for use as anti-fouling agents.


Assuntos
Antozoários/microbiologia , Antibacterianos , Aspergillus/química , Produtos Biológicos , Osteogênese/efeitos dos fármacos , Policetídeos , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Células Cultivadas , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , NF-kappa B/metabolismo , Oceanos e Mares , Policetídeos/química , Policetídeos/isolamento & purificação , Policetídeos/farmacologia , Ligante RANK
10.
Acta Crystallogr D Struct Biol ; 78(Pt 2): 174-186, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35102883

RESUMO

Cryo-electron microscopy (cryo-EM) is a Nobel Prize-winning technique for determining high-resolution 3D structures of biological macromolecules. A 3D structure is reconstructed from hundreds of thousands of noisy 2D projection images. However, existing 3D reconstruction methods are still time-consuming, and one of the major computational bottlenecks is recovering the unknown orientation of the particle in each 2D image. The dominant methods typically exploit an expensive global search on each image to estimate the missing orientations. Here, a novel end-to-end supervised learning method is introduced to directly recover the missing orientations from 2D cryo-EM images. A neural network is used to approximate the mapping from images to orientations. A robust loss function is proposed for optimizing the parameters of the network, which can handle both asymmetric and symmetric 3D structures. Experiments on synthetic data sets with various symmetry types confirm that the neural network is capable of recovering orientations from 2D cryo-EM images, and the results on a real cryo-EM data set further demonstrate its potential under more challenging imaging conditions.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Microscopia Crioeletrônica/métodos , Processamento de Imagem Assistida por Computador/métodos
11.
IEEE Trans Pattern Anal Mach Intell ; 44(6): 2953-2967, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33417538

RESUMO

Full projector compensation aims to modify a projector input image to compensate for both geometric and photometric disturbance of the projection surface. Traditional methods usually solve the two parts separately and may suffer from suboptimal solutions. In this paper, we propose the first end-to-end differentiable solution, named CompenNeSt++, to solve the two problems jointly. First, we propose a novel geometric correction subnet, named WarpingNet, which is designed with a cascaded coarse-to-fine structure to learn the sampling grid directly from sampling images. Second, we propose a novel photometric compensation subnet, named CompenNeSt, which is designed with a siamese architecture to capture the photometric interactions between the projection surface and the projected images, and to use such information to compensate the geometrically corrected images. By concatenating WarpingNet with CompenNeSt, CompenNeSt++ accomplishes full projector compensation and is end-to-end trainable. Third, to improve practicability, we propose a novel synthetic data-based pre-training strategy to significantly reduce the number of training images and training time. Moreover, we construct the first setup-independent full compensation benchmark to facilitate future studies. In thorough experiments, our method shows clear advantages over prior art with promising compensation quality and meanwhile being practically convenient.

12.
IEEE Trans Vis Comput Graph ; 27(5): 2725-2735, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33750703

RESUMO

Image-based relighting, projector compensation and depth/normal reconstruction are three important tasks of projector-camera systems (ProCams) and spatial augmented reality (SAR). Although they share a similar pipeline of finding projector-camera image mappings, in tradition, they are addressed independently, sometimes with different prerequisites, devices and sampling images. In practice, this may be cumbersome for SAR applications to address them one-by-one. In this paper, we propose a novel end-to-end trainable model named DeProCams to explicitly learn the photometric and geometric mappings of ProCams, and once trained, DeProCams can be applied simultaneously to the three tasks. DeProCams explicitly decomposes the projector-camera image mappings into three subprocesses: shading attributes estimation, rough direct light estimation and photorealistic neural rendering. A particular challenge addressed by DeProCams is occlusion, for which we exploit epipolar constraint and propose a novel differentiable projector direct light mask. Thus, it can be learned end-to-end along with the other modules. Afterwards, to improve convergence, we apply photometric and geometric constraints such that the intermediate results are plausible. In our experiments, DeProCams shows clear advantages over previous arts with promising quality and meanwhile being fully differentiable. Moreover, by solving the three tasks in a unified model, DeProCams waives the need for additional optical devices, radiometric calibrations and structured light.

13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 2579-2582, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30440935

RESUMO

Dental Panoramic radiography (DPR) image provides a potentially inexpensive source to evaluate bone density change through visual clue analysis on trabecular bone structure. However, dense overlapping of bone structures in DPR image and scarcity of labeled samples make learning of accurate mapping from DPR patches to osteoporosis condition challenging. In this paper, we propose a deep Octuplet Siamese Network (OSN) to learn and fuse discriminative features for osteoporosis condition prediction using multiple DRP patches. By exploring common features, OSN uses patches of eight locations together to train the shared feature extractor. Feature fusion for different location adopts both accumulation and concatenation with fully considering of patches' spatial symmetry. In our dedicated two-stage fine-tuning scheme, an augmented texture analysis dataset is employed to prevent overfitting in transferring weights learned on ImageNet to DPR dataset when using merely 108 samples. Leave-one-out test shows that our proposed OSN outperforms all other state of the art methods in osteoporosis category classification task.


Assuntos
Osteoporose , Densidade Óssea , Osso e Ossos , Humanos , Radiografia Panorâmica
14.
Planta ; 245(5): 939-950, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28108812

RESUMO

MAIN CONCLUSION: Fackel (FK) is involved in the flowering of Arabidopsis mainly via the gibberellin pathway and vernalization pathway. This new function of FK is partially dependent on the FLOWERING LOCUS C ( FLC ). A common transitional process from vegetative stage to reproductive stage exists in higher plants during their life cycle. The initiation of flower bud differentiation, which plays a key role in the reproductive phase, is affected by both external environmental and internal regulatory factors. In this study, we showed that the Arabidopsis weak mutant allele fk-J3158, impaired in the FACKEL (FK) gene, which encodes a C-14 reductase involved in sterol biosynthesis, had a long life cycle and delayed flowering time in different photoperiods. In addition, FK overexpression lines displayed an earlier flowering phenotype than that of the wild type. These processes might be independent of the downstream brassinosteroid (BR) pathway and the autonomous pathway. However, the fk-J3158 plants were more sensitive than wild type in reducing the bolting days and total leaf number under gibberellic acid (GA) treatment. Further studies suggested that FK mutation led to an absence of endogenous GAs in fk-J3158 and FK gene expression was also affected under GA and paclobutrazol (PAC) treatment. Moreover, the delayed flowering time of fk-J3158 could be rescued by a 3-week vernalization treatment, and the expression of FLOWERING LOCUS C (FLC) was accordingly down-regulated in fk-J3158. We also demonstrated that flowering time of fk-J3158 flc double mutant was significantly earlier than that of fk-J3158 under the long-day (LD) conditions. All these results indicated that FK may affect the flowering in Arabidopsis mainly via GA pathway and vernalization pathway. And these effects are partially dependent on the FLOWERING LOCUS C (FLC).


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Giberelinas/metabolismo , Proteínas de Domínio MADS/metabolismo , Oxirredutases/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Transdução de Sinais , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Flores/enzimologia , Flores/genética , Flores/fisiologia , Flores/efeitos da radiação , Genes Reporter , Proteínas de Domínio MADS/genética , Oxirredutases/genética , Fenótipo , Fotoperíodo , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Plantas Geneticamente Modificadas , Plântula/enzimologia , Plântula/genética , Plântula/fisiologia , Plântula/efeitos da radiação
15.
IEEE Trans Cybern ; 46(9): 2083-93, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26292356

RESUMO

Motivated by neuroscience discoveries during the last few years, many studies consider pulse-coupled neural networks with spike-timing as an essential component in information processing by the brain. There also exists some technical challenges while simulating the networks of artificial spiking neurons. The existing studies use a Hodgkin-Huxley (H-H) model to describe spiking dynamics and neuro-computational properties of each neuron. But they fail to address the effect of specific non-Gaussian noise on an artificial H-H neuron system. This paper aims to analyze how an artificial H-H neuron responds to add different types of noise using an electrical current and subunit noise model. The spiking and bursting behavior of this neuron is also investigated through numerical simulations. In addition, through statistic analysis, the intensity of different kinds of noise distributions is discussed to obtain their relationship with the mean firing rate, interspike intervals, and stochastic resonance.


Assuntos
Potenciais de Ação/fisiologia , Modelos Neurológicos , Redes Neurais de Computação , Neurônios/fisiologia , Encéfalo/fisiologia , Humanos , Rede Nervosa/fisiologia , Processos Estocásticos
16.
Plant Physiol ; 167(3): 1058-75, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25560878

RESUMO

In plants, cell morphogenesis is dependent on intercellular auxin accumulation. The polar subcellular localization of the PIN-FORMED (PIN) protein is crucial for this process. Previous studies have shown that the protein kinase PINOID (PID) and protein phosphatase6-type phosphatase holoenzyme regulate the phosphorylation status of PIN1 in root tips and shoot apices. Here, we show that a type-one protein phosphatase, TOPP4, is essential for the formation of interdigitated pavement cell (PC) pattern in Arabidopsis (Arabidopsis thaliana) leaf. The dominant-negative mutant topp4-1 showed severely inhibited interdigitated PC growth. Expression of topp4-1 gene in wild-type plants recapitulated the PC defects in the mutant. Genetic analyses suggested that TOPP4 and PIN1 likely function in the same pathway to regulate PC morphogenesis. Furthermore, colocalization, in vitro and in vivo protein interaction studies, and dephosphorylation assays revealed that TOPP4 mediated PIN1 polar localization and endocytic trafficking in PCs by acting antagonistically with PID to modulate the phosphorylation status of PIN1. In addition, TOPP4 affects the cytoskeleton pattern through the Rho of Plant GTPase-dependent auxin-signaling pathway. Therefore, we conclude that TOPP4-regulated PIN1 polar targeting through direct dephosphorylation is crucial for PC morphogenesis in the Arabidopsis leaf.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/citologia , Arabidopsis/enzimologia , Polaridade Celular , Proteínas de Membrana Transportadoras/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Folhas de Planta/citologia , Actinas/metabolismo , Transporte Biológico/efeitos dos fármacos , Polaridade Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Endocitose/efeitos dos fármacos , Epistasia Genética/efeitos dos fármacos , Teste de Complementação Genética , Ácidos Indolacéticos/farmacologia , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Modelos Biológicos , Morfogênese/efeitos dos fármacos , Mutação/genética , Fenótipo , Fosforilação/efeitos dos fármacos , Desenvolvimento Vegetal/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Proteína Fosfatase 1/metabolismo
17.
Arch Phys Med Rehabil ; 96(5): 920-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25576086

RESUMO

OBJECTIVE: To identify the predictors for successful neurodynamic management in patients with patellofemoral pain syndrome. DESIGN: Prospective cohort, prediction rule study. SETTING: Hospital. PARTICIPANTS: Patients with patellofemoral pain syndrome (N=51) underwent clinical examination and measurement of physical parameters, including femoral slump test, lower-extremity alignment, flexibility and muscle strength, and functional level. INTERVENTION: Patients received 6 treatment sessions of femoral nerve mobilization within 2 weeks. MAIN OUTCOME MEASURES: Pain level during functional testing was assessed before and after the first and sixth session of treatment. Patients were then grouped into responder and nonresponder groups. Criteria for the responder group was a pain score decrease ≥50% or Global Rating Scale score ≥4. Chi-square and independent t tests were used to identify potential variables with a significance level of .10, and stepwise logistic regression was used to find predictors with a significance level of .05. RESULTS: Twenty-five patients responded to the initial treatment (immediate effect), and 28 patients responded after 6 sessions (longer-term effect). A positive femoral slump test was identified as the predictor for the immediate treatment effect. The prediction factors for the longer-term effect included responding to femoral nerve mobilization the first time and a bilateral difference in hip extension angles. Application of the clinical predictors improved the success rate to 90% for 1 treatment session and 93% for 6 treatment sessions. CONCLUSIONS: Clinicians could use the positive femoral slump test and a bilateral difference in hip extension angles during the femoral slump test to determine whether or not patients with patellofemoral pain syndrome might benefit from femoral nerve mobilization.


Assuntos
Nervo Femoral/fisiopatologia , Síndrome da Dor Patelofemoral/fisiopatologia , Síndrome da Dor Patelofemoral/reabilitação , Modalidades de Fisioterapia , Adulto , Feminino , Fêmur , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular , Medição da Dor , Síndrome da Dor Patelofemoral/diagnóstico por imagem , Estudos Prospectivos , Radiografia , Amplitude de Movimento Articular
18.
Planta ; 240(4): 763-79, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25056926

RESUMO

MAIN CONCLUSION: Our results provide further insight into the regulation of DELLA proteins in Arabidopsis . We clarified that phosphorylation modification of the six conserved sites is important for RGA functions and stability. The DELLA proteins, important plant growth and development repressors mediate the gibberellin (GA) signaling pathway. Although these proteins exhibit phosphorylation and de-phosphorylation states at the molecular level, little is known regarding the effects of different modifications of DELLA proteins on the regulation of their bioactivity and stability at the genetic level. In this study, six conserved serine (Ser)/threonine (Thr) sites of REPRESSOR OF ga1-3 (RGA) were substituted with alanine (RGA6A) or aspartic acid (RGA6D) to mimic the states of constitutive de-phosphorylation and phosphorylation, respectively. We found that the overexpression of de-phosphomimic RGA in Col-0 plants caused GA-overdose phenotypes, which were similar to DELLA-deficient mutant. These phenotypes were probably attributed to de-phosphomimic RGA, which retained its transcriptional activation activity that induces GA biosynthetic genes, but lost the transcription repressor function that inhibits GA-responsive genes. Further, de-phosphomimic RGA was unstable and easily degradable unlike the wild-type RGA, suggesting that the de-phosphorylated form is necessary for its degradation. In contrast, phosphomimic RGA overexpression caused GA-deficient phenotypes with non-degradable RGA. These phenotypes were probably due to phosphomimic RGA, which represses GA-responsive gene expression instead of inducing GA biosynthetic genes. In addition, phosphomimic RGA was stable and hardly degradable, which aggravated the RGA-inhibiting function in GA signaling. In conclusion, we show that the six conserved Ser/Thr sites are important for the different bioactivities of the RGA protein that regulate the GA response, and also for RGA stability via the mimicking of phosphorylation/de-phosphorylation.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Giberelinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais , Substituição de Aminoácidos , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Mutação , Fenótipo , Fosforilação , Plantas Geneticamente Modificadas , Estabilidade Proteica , Proteínas Repressoras/genética , Serina/metabolismo , Treonina/metabolismo , Triazóis/farmacologia , Técnicas do Sistema de Duplo-Híbrido
19.
ChemSusChem ; 1(6): 527-33, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18702151

RESUMO

A series of Ni/SBA-15/Al(2)O(3)/FeCrAl metal monolithic catalysts with Ni loadings varying between 3 % and 16 % were prepared, and their structure was characterized by various techniques. The catalytic activity of the catalyst for methane reforming with CO(2) leading to synthesis gas was evaluated using a fixed-bed reactor. The results indicate good catalytic activity of the Ni/SBA-15/Al(2)O(3)/FeCrAl samples under the reaction conditions. The catalyst with a Ni loading of 8.0 % displays excellent activity and stability at 800 degrees C over 1400 h time on stream. After reaction, the hexagonal mesoporous structure of SBA-15 is still present and the pore walls of SBA-15 prevent the aggregation of nickel. Interactions between NiO, SBA-15, and the Al(2)O(3)/FeCrAl support modify the redox properties of the Ni/SBA-15/Al(2)O(3)/FeCrAl catalysts.


Assuntos
Dióxido de Carbono/química , Metano/química , Níquel/química , Óxido de Alumínio/química , Catálise , Oxirredução , Porosidade , Dióxido de Silício/química
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