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1.
J Plant Physiol ; 290: 154098, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37774564

RESUMEN

Acorus tatarinowii (A. tatarinowii) is a medicinal plant of the Araceae family. Currently, pharmacology focuses on the study of volatile oils, but there are few reports of another important secondary metabolite, lignan. Dirigent protein is thought to play an important role in plant secondary metabolism and responds to a variety of biotic and abiotic stresses. However, the DIR gene family of A. tatarinowii has not been systematically analyzed, and it is unknown whether it affects lignan synthesis. In this study, a total of 27 AtsDIRs were identified by comprehensive analysis of the genome of the medicinal plant A. tatarinowii, and the candidate gene AtsDIR23 that may be involved in lignan synthesis was screened through bioinformatics and transcriptome analysis. It is worth noting that AtsDIR23 is significantly expressed in rhizomes and is a member of the DIR-a subfamily. Subsequently, subcellular localization revealed that AtsDIR23 was localized in chloroplasts. The functional verification of AtsDIR23 b y the transient transformation of A. tatarinowii and the stable transformation of Arabidopsis thaliana showed that the content of lignans in overexpressed plants increased. Co-expression analysis screening revealed the MYB transcription factor (AtsMYB91) that is highly correlated with AtsDIR23 expression, while yeast one-hybrid assays and double luciferase experiments showed that AtsMYB91 negatively regulated the expression of AtsDIR23 b y binding to the AtsDIR23 promoter. In conclusion, AtsDIR23 can promote the accumulation of lignans, which provides a reference for further research on the regulation of lignans by DIR genes.


Asunto(s)
Arabidopsis , Lignanos , Aceites Volátiles , Arabidopsis/genética , Regiones Promotoras Genéticas/genética
2.
J Digit Imaging ; 36(3): 1208-1215, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36650301

RESUMEN

Universal lesion detection (ULD) in computed tomography (CT) images is an important and challenging prerequisite for computer-aided diagnosis (CAD) to find abnormal tissue, such as tumors of lymph nodes, liver tumors, and lymphadenopathy. The key challenge is that lesions have a tiny size and high similarity with non-lesions, which can easily lead to high false positives. Specifically , non-lesions are nearby normal anatomy that include the bowel, vasculature, and mesentery, which decrease the conspicuity of small lesions since they are often hard to differentiate. In this study, we present a novel scale-attention module that enhances feature discrimination between lesion and non-lesion regions by utilizing the domain knowledge of radiologists to reduce false positives effectively. Inspired by the domain knowledge that radiologists tend to divide each CT image into multiple areas, then detect lesions in these smaller areas separately, a local axial scale-attention (LASA) module is proposed to re-weight each pixel in a feature map by aggregating local features from multiple scales adaptively. In addition, to keep the same weight, a combination of axial pixels in the height- and width-axes is designed, attached with position embedding. The model can be used in CNNs easily and flexibly. We test our method on the DeepLesion dataset. The sensitivities at 0.5, 1, 2, 4, 8, and 16 false positives (FPs) per image and average sensitivity at [0.5, 1, 2, 4] are calculated to evaluate the accuracy. The sensitivities are 78.30%, 84.96%, 89.86%, 93.14%, 95.36%, and 95.54% at 0.5, 1, 2, 4, 8, and 16 FPs per image; the average sensitivity is 86.56%, outperforming the former methods. The proposed method enhances feature discrimination between lesion and non-lesion regions by adding LASA modules. These encouraging results illustrate the potential advantage of exploiting the domain knowledge for lesion detection.


Asunto(s)
Diagnóstico por Computador , Tomografía Computarizada por Rayos X , Humanos , Tomografía Computarizada por Rayos X/métodos , Diagnóstico por Computador/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos
3.
Materials (Basel) ; 13(5)2020 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-32155858

RESUMEN

The low yield strength (~300 MPa) of twinning-induced plasticity (TWIP) steels greatly limits their structural applications in the industrial field. Conventional strengthening mechanisms usually cause an enhancement of yield strength but also a severe loss of ductility. In this research, gradient substructures were introduced in the Fe-22Mn-0.6C TWIP steels by different pre-torsional deformation in order to overcome the above limitations. The substructure evolution, mechanical properties, and their origins in gradient-substructured (GS) TWIP steels were measured and compared by electron backscattered diffraction (EBSD), monotonous and loading-unloading-reloading (LUR) tensile tests. It was found that a simple torsional treatment could prepare gradient twins and dislocations in coarse-grained TWIP steel samples depending on torsional strain. The uniaxial tensile tests indicated that a superior combination of high yield strength, high ultimate strength, and considerable ductility was simultaneously obtained in the GS samples. The high yield strength and high ultimate tensile strength were attributed to synergetic strengthening mechanisms, viz., dislocation strengthening, due to the accumulation of high density of dislocations, and very high back stress strengthening due to gradient substructure distribution, which was accommodated through pile-ups of extra geometrically necessary dislocations (GNDs) across the sample-scale. Additionally, high ductility originated from gradient substructure-induced back stress hardening. The present study is also beneficial to the design efforts of high strength and high ductility of other heterogeneous-structured TWIP alloy systems.

4.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 33(2): 244-54, 2016 Apr.
Artículo en Chino | MEDLINE | ID: mdl-29708323

RESUMEN

For the questions of deeply researching abnormal neuromuscular coupling and better evaluating motor function of stroke patients with motor dysfunction,an effective intermuscular coherence analysis method and index are studied to explore the neuromuscular oscillation and the pathomechanism of motor dysfunction,based on which an assessment standard of muscle function is established.Firstly,the contrastive analysis about the intermuscular coherence of antagonistic muscle of affected and intact upper limbs of stroke patients was conducted.Secondly,a significant indicator of Fisher's Z-transformed coherence significant indicator was defined to quantitatively describe the coupling differences in certain functional frequency domain between surface electromyogram(sEMG)of affected and intact sides.Further more,the relationship between intermuscular coherence and motor task was studied.Through the analysis of intermuscular coherence during elbow flexion-extension of affected and intact sides,we found that the intermuscular coherence was associated with motor task and the stroke patients exhibited significantly lower betaband intermuscular coherence in performing the task with their affected upper limbs.More conclusion can be drawn that beta-band intermuscular coherence has been found concerned with Fugle-Meyer scale,which indicates that betaband intermuscular coherence could be an index assisting in evaluating motor function of patients.


Asunto(s)
Músculo Esquelético/fisiología , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/fisiopatología , Electromiografía , Potenciales Evocados Motores , Humanos , Corteza Motora/fisiología , Corteza Motora/fisiopatología , Músculo Esquelético/fisiopatología
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