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1.
IEEE Trans Pattern Anal Mach Intell ; 45(12): 15406-15425, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37494160

RESUMO

Estimating human pose and shape from monocular images is a long-standing problem in computer vision. Since the release of statistical body models, 3D human mesh recovery has been drawing broader attention. With the same goal of obtaining well-aligned and physically plausible mesh results, two paradigms have been developed to overcome challenges in the 2D-to-3D lifting process: i) an optimization-based paradigm, where different data terms and regularization terms are exploited as optimization objectives; and ii) a regression-based paradigm, where deep learning techniques are embraced to solve the problem in an end-to-end fashion. Meanwhile, continuous efforts are devoted to improving the quality of 3D mesh labels for a wide range of datasets. Though remarkable progress has been achieved in the past decade, the task is still challenging due to flexible body motions, diverse appearances, complex environments, and insufficient in-the-wild annotations. To the best of our knowledge, this is the first survey that focuses on the task of monocular 3D human mesh recovery. We start with the introduction of body models and then elaborate recovery frameworks and training objectives by providing in-depth analyses of their strengths and weaknesses. We also summarize datasets, evaluation metrics, and benchmark results. Open issues and future directions are discussed in the end, hoping to motivate researchers and facilitate their research in this area.


Assuntos
Algoritmos , Telas Cirúrgicas , Humanos , Benchmarking , Modelos Estatísticos , Movimento (Física)
2.
IEEE Trans Pattern Anal Mach Intell ; 45(10): 12287-12303, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37126625

RESUMO

We present PyMAF-X, a regression-based approach to recovering a parametric full-body model from a single image. This task is very challenging since minor parametric deviation may lead to noticeable misalignment between the estimated mesh and the input image. Moreover, when integrating part-specific estimations into the full-body model, existing solutions tend to either degrade the alignment or produce unnatural wrist poses. To address these issues, we propose a Pyramidal Mesh Alignment Feedback (PyMAF) loop in our regression network for well-aligned human mesh recovery and extend it as PyMAF-X for the recovery of expressive full-body models. The core idea of PyMAF is to leverage a feature pyramid and rectify the predicted parameters explicitly based on the mesh-image alignment status. Specifically, given the currently predicted parameters, mesh-aligned evidence will be extracted from finer-resolution features accordingly and fed back for parameter rectification. To enhance the alignment perception, an auxiliary dense supervision is employed to provide mesh-image correspondence guidance while spatial alignment attention is introduced to enable the awareness of the global contexts for our network. When extending PyMAF for full-body mesh recovery, an adaptive integration strategy is proposed in PyMAF-X to produce natural wrist poses while maintaining the well-aligned performance of the part-specific estimations. The efficacy of our approach is validated on several benchmark datasets for body, hand, face, and full-body mesh recovery, where PyMAF and PyMAF-X effectively improve the mesh-image alignment and achieve new The project page with code and video results can be found at https://www.liuyebin.com/pymaf-x.

3.
Front Plant Sci ; 13: 946194, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812908

RESUMO

Plant AT-rich protein and zinc-binding protein (PLATZ) is a class of plant-specific zinc-dependent DNA-binding protein that binds to A/T-rich DNA sequences. PLATZ plays an important role in seed development, water tolerance, and cell proliferation in early plant growth. In this study, 11 GbPLATZs were identified from the ginkgo genome with complete PLATZ-conserved domains, which represents a smaller number compared with angiosperms. Multi-species phylogenetic analysis showed that PLATZ genes were conserved in seed plants, and the 11 members were represented by four groups, among which groups I and II were closely related. Analysis of gene structures, sequence module characteristics, and expression patterns showed that GbPLATZs were similar within and differed between groups. RNA-seq and qRT-PCR results showed that GbPLATZs had distinct expression patterns. Most genes were associated with seed development, among which six genes were highly related. Subcellular localization experiments showed that six GbPLATZ proteins related to seed development were localized in the nucleus, suggesting that they might function as traditional transcription factors. This study provides a basis for understanding the structural differentiation, evolutionary characteristics, expression profile, and potential functions of PLATZ transcription factors in Ginkgo biloba.

4.
Int J Mol Sci ; 23(10)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35628284

RESUMO

Lateral organ boundaries domain (LBD) proteins are plant-specific transcription factors involved in various transcriptional regulation processes. We identified a total of 37 GbLBD genes in ginkgo, and based on gene structure and phylogenetic analysis, the GbLBD gene family was classified into class I (33, with the largest number of Id genes (16)) and class II (4). The ginkgo LBD gene was also analyzed regarding its chromosomal distributions, gene duplications, promoters, and introns/exons. In addition, gene expression profiling and real-time quantitative PCR analysis showed that the expression of 14 GbLBD genes differed in six different tissues and three developmental stages. The GbLBD gene of class II were highly expressed relative to the class I gene in all tissues and developmental stages, while class Id gene were generally at low levels or were not expressed, especially in seed developmental stages. The expression pattern analysis of cold/drought treatment and IAA/ABA hormone treatment showed that abiotic stress treatment could significantly induce the expression of GbLBD gene, of which class II genes played a key role in stress treatment. Our study provides a solid foundation for further evolutionary and functional analysis of the ginkgo LBD gene family.


Assuntos
Regulação da Expressão Gênica de Plantas , Ginkgo biloba , Ginkgo biloba/genética , Filogenia , Sementes , Fatores de Transcrição/genética
5.
Int J Mol Sci ; 23(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35163431

RESUMO

The gibberellic acid-stimulated Arabidopsis (GASA) gene family plays an important regulatory role in the growth and development of plants. In this study, we identified 19 GASA genes using bioinformatics-based methods in Populus trichocarpa, and these PtGASA genes could be divided into three categories based on their phylogenetic relationships. Based on an analysis of the structure and motifs of these genes, it was concluded that PtGASA class II members are more conserved than class I and class III members are, and the results of collinearity analysis showed that members of class II are collinearly related in poplar. Expression analysis of Populus trichocarpa roots, stems, and leaves showed that most of the PtGASA genes are expressed at higher levels in the stems or roots than in the leaves; a similar expression pattern was found in Vitis vinifera, indicating that the GASA-family members mainly play a role in the morphogenesis of poplar. Considering the phenomenon of gene amplification, we found that the higher the similarity of homologous genes was, the more similar the expression patterns. This study represents the first whole-genome identification and expression-profile analysis of the GASA-gene family in poplar, a model species, laying a foundation for functional studies of poplar GASA genes and serving as a reference for related research on other woody plant species.


Assuntos
Sequenciamento do Exoma/métodos , Perfilação da Expressão Gênica/métodos , Proteínas de Plantas/genética , Populus/crescimento & desenvolvimento , Sequência de Aminoácidos , Sequência Conservada , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Modelos Moleculares , Família Multigênica , Filogenia , Proteínas de Plantas/química , Populus/genética , Conformação Proteica , Distribuição Tecidual
6.
Acta cir. bras ; 30(12): 838-843, Dec. 2015. graf
Artigo em Inglês | LILACS | ID: lil-769500

RESUMO

ABSTRACT PURPOSE: To test whether hemorrhagic shock (HS) increases the Cyclooxygenase-2 (COX-2) expression in the intestine and whether this enhanced COX-2 expression mediates the intestinal dysmotility after HS. METHODS: Male Wistar rats were randomly divided into HS sham group and HS group. At 180 min following HS establishment, the duodenum samples were harvested to assess the motility function, protein expression of COX-2 and the downstream products of COX-2, prostaglandins. RESULTS: Examination of motility function ex vivo showed that the contractile response to acetylcholine of smooth muscle strips of rats subjected to HS was significantly suppressed. A COX-2 inhibitor, NS-398, abolished this depressed contractile response after HS. Western blotting revealed an increased protein expression of COX-2 in intestinal tissues of HS rats. Immunohistochemical examination indicated that intestine tissues of HS rats were manifested by part of villous expansion and disruption, a large amount of COX-2 positive cells appearance in lamina propria and submucosa. Furthermore, the contents of prostaglandin E2 was significantly increased in intestinal tissues of HS rats. CONCLUSION: The enhanced COX-2/ prostaglandin E2 involves in the hemorrhagic shock induced intestinal dysmotility.


Assuntos
Animais , Masculino , /metabolismo , Duodeno/fisiopatologia , Motilidade Gastrointestinal/fisiologia , Choque Hemorrágico/enzimologia , Acetilcolina/farmacologia , Dinoprostona/metabolismo , Modelos Animais , Contração Muscular/efeitos dos fármacos , Nitrobenzenos/farmacologia , Distribuição Aleatória , Ratos Wistar , Choque Hemorrágico/fisiopatologia , Sulfonamidas/farmacologia
7.
Acta Cir Bras ; 30(12): 838-43, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26735056

RESUMO

PURPOSE: To test whether hemorrhagic shock (HS) increases the Cyclooxygenase-2 (COX-2) expression in the intestine and whether this enhanced COX-2 expression mediates the intestinal dysmotility after HS. METHODS: Male Wistar rats were randomly divided into HS sham group and HS group. At 180 min following HS establishment, the duodenum samples were harvested to assess the motility function, protein expression of COX-2 and the downstream products of COX-2, prostaglandins. RESULTS: Examination of motility function ex vivo showed that the contractile response to acetylcholine of smooth muscle strips of rats subjected to HS was significantly suppressed. A COX-2 inhibitor, NS-398, abolished this depressed contractile response after HS. Western blotting revealed an increased protein expression of COX-2 in intestinal tissues of HS rats. Immunohistochemical examination indicated that intestine tissues of HS rats were manifested by part of villous expansion and disruption, a large amount of COX-2 positive cells appearance in lamina propria and submucosa. Furthermore, the contents of prostaglandin E2 was significantly increased in intestinal tissues of HS rats. CONCLUSION: The enhanced COX-2/ prostaglandin E2 involves in the hemorrhagic shock induced intestinal dysmotility.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Duodeno/fisiopatologia , Motilidade Gastrointestinal/fisiologia , Choque Hemorrágico/enzimologia , Acetilcolina/farmacologia , Animais , Dinoprostona/metabolismo , Masculino , Modelos Animais , Contração Muscular/efeitos dos fármacos , Nitrobenzenos/farmacologia , Distribuição Aleatória , Ratos Wistar , Choque Hemorrágico/fisiopatologia , Sulfonamidas/farmacologia
8.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 33(9): 1247-51, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24273983

RESUMO

OBJECTIVE: To study the effect of matrine on Fas, VEGF, and activities of telomerase of MCF-7 cells. METHODS: In vitro cultured human breast cancer MCF-7 cells were randomly divided into the experimental group and the control group. The matrine solution was added in cells of the experimental group. Equal volume of culture medium was added in cells of the control group or the negative control group. Zedoary Turmeric Oil, the telomerase inhibitor was added in cells of the positive control group. Morphological changes were observed under an inverted microscope. The telomerase activity was detected by TRAP-ELISA. Expressions of Fas and VEGF protein were detected by immunocytochemical assay. RESULTS: Matrine obviously inhibited the growth and induced apoptosis of breast cancer cells. MCF-7 cells were treated by matrine of different concentrations at 24, 48, and 72 h, the telomerase activity gradually decreased along with increased matrine concentration and prolonged action time, showing dose-effect and time-effect positive relations. Matrine could up-regulate Fas protein expression and downregulate VEGF protein expression of MCF-7 cells. CONCLUSION: Matrine showed obvious effect in inhibiting the growth of MCF-7 cells and promoting the apoptosis, which might be achieved by up-regulating the expression of Fas protein, inhibiting telomerase activity induced apoptosis of breast cancer cells, down-regulating the expression of VEGF protein, and inhibiting the tumor vascular formation.


Assuntos
Alcaloides/farmacologia , Quinolizinas/farmacologia , Telomerase/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor fas/metabolismo , Apoptose/efeitos dos fármacos , Feminino , Humanos , Células MCF-7/efeitos dos fármacos , Matrinas
9.
ScientificWorldJournal ; 2013: 157527, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24089600

RESUMO

Ultrasound-assisted extraction (UAE) of phenolic compounds from Inula helenium was studied. Effects of ethanol concentration, ultrasonic time, solid-liquid ratio, and number of extractions were investigated. An orthogonal array was constructed to optimize UAE process. The optimized extraction conditions were as follows: ethanol concentration, 30%; solid-liquid ratio, 1 : 20; number of extractions, 2 times; extraction time, 30 min. Under the optimal conditions, the yield of total phenolic compounds and chlorogenic acid was 6.13 ± 0.58 and 1.32 ± 0.17 mg/g, respectively. The results showed that high amounts of phenolic compounds can be extracted from I. helenium by ultrasound-assisted extraction technology.


Assuntos
Inula/química , Fenóis/química , Extratos Vegetais/química , Ultrassom , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação
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