606 research outputs found
Promoter activity analysis and transcriptional profile of Ginkgo biloba 1-Deoxy-D- Xylulose 5-Phosphate reductoisomerase gene (GbDXR) under abiotic stresses
Terpene trilactones (TTL) is a pharmacological ingredient in Ginkgo biloba and its content has become one of the key indices for medicinal value evaluation of ginkgo. 1-Deoxy-D-xylulose 5-phosphate reductoisomerase (DXR) catalyzes the first step specific for isopentenyl diphosphate production in methylerythritol phosphate pathway, which provide the basic structure required for TTLs biosynthesis. To understand the mechanism controlling the GbDXR gene expression, the GbDXR promoter sequence was isolated and subjected to transient expression with the green fluorescent protein (GFP) in tobacco plants. Characteristic analysis revealed various cis-acting elements that related to light-regulated transcription, hormone signaling (auxin, ethylene), adversity stress and defense signaling (heat/dehydration stress) in the GbDXR promoter region. In transient expression assay, deletion of different portions of the upstream GbDXR promoter identified that the promoter region -3230bp to -865bp conserve the positive regulation function, which could promote the expression of GFP in the cytoplasm of tobacco leaf epidermal cells. The regulation function of the promoter region -865bp to -262bp remained to be elucidated. EMSA analysis suggested possible interactions of GbERF10 and GbERF17 with the ERF-binding elements in the upstream of GbDXR promoter. For abiotic stresses treatment, the expression of GbDXR gene could be significantly induced by UV-B and drought stress. In general, the GbDXR gene expressed differently in different ginkgo tissues but exhibited the highest transcriptional level in the root, with the maximum TTLs content simultaneously. The positive relationship between gene expression level and TTLs content indicated that the GbDXR is responsible for TTLs biosynthesis in G. biloba
EEGFuseNet: Hybrid Unsupervised Deep Feature Characterization and Fusion for High-Dimensional EEG With an Application to Emotion Recognition
How to effectively and efficiently extract valid and reliable features from high-dimensional electroencephalography (EEG), particularly how to fuse the spatial and temporal dynamic brain information into a better feature representation, is a critical issue in brain data analysis. Most current EEG studies work in a task driven manner and explore the valid EEG features with a supervised model, which would be limited by the given labels to a great extent. In this paper, we propose a practical hybrid unsupervised deep convolutional recurrent generative adversarial network based EEG feature characterization and fusion model, which is termed as EEGFuseNet. EEGFuseNet is trained in an unsupervised manner, and deep EEG features covering both spatial and temporal dynamics are automatically characterized. Comparing to the existing features, the characterized deep EEG features could be considered to be more generic and independent of any specific EEG task. The performance of the extracted deep and low-dimensional features by EEGFuseNet is carefully evaluated in an unsupervised emotion recognition application based on three public emotion databases. The results demonstrate the proposed EEGFuseNet is a robust and reliable model, which is easy to train and performs efficiently in the representation and fusion of dynamic EEG features. In particular, EEGFuseNet is established as an optimal unsupervised fusion model with promising cross-subject emotion recognition performance. It proves EEGFuseNet is capable of characterizing and fusing deep features that imply comparative cortical dynamic significance corresponding to the changing of different emotion states, and also demonstrates the possibility of realizing EEG based cross-subject emotion recognition in a pure unsupervised manner
High-resolution X-ray microdiffraction analysis of natural teeth
In situ microzone X-ray diffraction analysis of natural teeth is presented. From our experiment, layer orientation and continuous crystal variations in teeth could be conveniently studied using fast online measurements by high-resolution X-ray microdiffraction equipment
Extraction, Isolation and Identification of Antimicrobial Substances from Bacillus amyloliquefaciens CMN1308
Four separation methods of antimicrobial substances produced by CMN1308 (Bacillus amyloliquefaciens) were evaluated and selected according to number of antimicrobial substances and its activity in vitro. The results showed that extraction by acid precipitation of the fermentation supernatant of CMN1308 was the best with a diameter of inhibition zone of pathogen fungi P. expansum of 12.3 mm in a laboratory bioassay. Applying a silica thin layer chromatography (TLC), SDS-PAGE and other separation technologies we isolate antimicrobial substances, and the separated band were cut off for mass spectrometry analysis. The TLC of crude extract of CMN1308 show a topical band corresponding with the surfactin standard (Rf value =0.75), proved that the strain CMN1308 can produce this surface active compound. The mycoprotein extracted from CMN1308 was separated by Tricine-SDS-PAGE modified with the addition of urea in the separation gel. After mass spectrometric analysis and protein characterization, the isolated mycoprotein showed a maximum ion peak at M/Z of 2679 and molecular weight of 29.5 kDa, matching with protein flagellin. The extracellular antimicrobial protein of strain CMN1308 display four bands after urea-Tricine-SDS-PAGE, but after mass spectrometry analysis only two bands were identified. Band “A” with a maximum ion peak at M/Z of 1926 and molecular weight of 49.8 kDa, aligned with NCBI database, matching with DLDH (dihydrolipoamide dehydrogenase enzyme). Band “D” show the maximum ion peak at M/Z of 2936 and molecular weight of 22.4 kD, matching with a chitin binding protein. Thus, the strain CMN1308 has the potential to be developed as a commercial biological control agent for chestnut common pathogenic fungi
Transcriptome-based Discovery of AP2/ERF Transcription Factors Related to Terpene Trilactones Synthesis in Ginkgo biloba
Ginkgo biloba is a unique tree in China with medicinally and phylogenetically important characteristics. Terpene trilactones (TTL) is a key active pharmaceutical ingredient in Ginkgo, so the content of TTL in Ginkgo has become one of the important indices for evaluating quality of the medicinal materials. By transcriptome sequencing on samples treated by chlormequat, ultraviolet (UV) and drought, totally 59820 contigs and 37564 unigenes were obtained. Furthermore, 18234 unigenes were annotated through COG, KEGG and GO analysis. There were 78 AP2/ERF transcription factors, 23 factors of up-regulation and 66 factors of down-regulation that were related with synthetic pathway of TTL in Ginkgo. Phylogenetic tree clustering analysis indicated that there were 42 AP2s could be clustered into ERF, DREB and RVA subfamilies. EMSA analysis demonstrated that GbERF13, GbERF25 and GbERF27 could bind with regulatory elements, such as E-box, in the upstream of GbMECPs promoter. Expression analysis showed that the expression level of GbERF25 was the highest in root, and GbERF25 and GbERF27 were expressed in relatively high transcription levels in leaf and other tissues. The results of qRT-PCR indicated that CCC treatment could significantly improve expression levels of ERF25 and ERF27, and UV and drought could induce transcription levels of ERF13 and ERF25, respectively. The results implied that ERF25 and ERF27 might involve in the induction and regulation of CCC treatment on synthesis of bilobalide in G. biloba. ERF13 might participate in the regulation of bilobalide synthesis induced by UV, and EFR25 might involve in the regulation of the synthesis induced by drought. During annual cycle of expression, the transcription levels of ERF13, ERF25 and ERF27 had significantly positive correlation with diterpene level with correlation coefficient 0.975. It implied that these transcription factors mainly acted on the MEP pathway that regulated synthesis of bilobalide. The aim of the research was to indicate the mechanism of environment or cultivation measure regulating target gene of TTL metabolic pathway by AP2/ERF, and establish metabolic network of AP2/ERF regulating TTL synthesis
HA-HI: Synergising fMRI and DTI through Hierarchical Alignments and Hierarchical Interactions for Mild Cognitive Impairment Diagnosis
Early diagnosis of mild cognitive impairment (MCI) and subjective cognitive
decline (SCD) utilizing multi-modal magnetic resonance imaging (MRI) is a
pivotal area of research. While various regional and connectivity features from
functional MRI (fMRI) and diffusion tensor imaging (DTI) have been employed to
develop diagnosis models, most studies integrate these features without
adequately addressing their alignment and interactions. This limits the
potential to fully exploit the synergistic contributions of combined features
and modalities. To solve this gap, our study introduces a novel Hierarchical
Alignments and Hierarchical Interactions (HA-HI) method for MCI and SCD
classification, leveraging the combined strengths of fMRI and DTI. HA-HI
efficiently learns significant MCI- or SCD- related regional and connectivity
features by aligning various feature types and hierarchically maximizing their
interactions. Furthermore, to enhance the interpretability of our approach, we
have developed the Synergistic Activation Map (SAM) technique, revealing the
critical brain regions and connections that are indicative of MCI/SCD.
Comprehensive evaluations on the ADNI dataset and our self-collected data
demonstrate that HA-HI outperforms other existing methods in diagnosing MCI and
SCD, making it a potentially vital and interpretable tool for early detection.
The implementation of this method is publicly accessible at
https://github.com/ICI-BCI/Dual-MRI-HA-HI.git
Neural Activation During Tonic Pain and Interaction Between Pain and Emotion in Bipolar Disorder: An fMRI Study
Objective: Pain and affective disorders have clear clinical relevance; however, very few studies have investigated the association between pain and bipolar disorder. This study investigated the brain activity of patients with bipolar disorder (BPs) undergoing tonic pain and assessed the interaction between pain and emotion.Methods: Ten BPs and ten healthy controls (HCs) were exposed to emotional pictures (positive, neutral, or negative), tonic pain only (pain session), and emotional pictures along with tonic pain (combined session). A moderate tonic pain was induced by the infusion of hypertonic saline (5% NaCl) into the right masseter muscle with a computer-controlled system. Whole-brain blood oxygenation level dependent (BOLD) signals were acquired using 3T functional resonance imaging (fMRI).Results: Ten BPs and ten healthy participants were included in the final analysis. During the pain session, BPs accepted more saline, but showed lower pain rating scores than HCs. When experiencing pain, BPs showed a significant decrease in the BOLD signal in the bilateral insula, left inferior frontal gyrus (IFG), and left cerebellum as compared with HCs. In the combined session, the activated regions for positive mood (pain with positive mood > baseline) in BPs were the left cerebellum, right temporal gyrus, and left occipital gyrus; the activated regions for negative mood (pain with negative mood > baseline) were the right occipital gyrus, left insula, left IFG, and bilateral precentral gyrus.Conclusions: This study presents the preliminary finding of the interaction between pain and emotion in BPs. BPs exhibited lower sensitivity to pain, and the activation of insula and IFG may reflect the interaction between emotion and pain stimulus
High-Density Kinetic Analysis of the Metabolomic and Transcriptomic Response of Ginkgo biloba Flavonoids Biosynthesis to Selenium Treatments
As one of the rare and precious wood species since the ancient times, Gingko is also known as “living fossil”, which is a special plant resource of China. Gingko leaves, containing rich flavonoids, are valued with great medicinal significances. This paper treated Ginkgo seedlings by exogenous Sodium selenite (SS) in two ways: Foliage dressing (FD) and Root application (RA). Then transcriptome sequencing and metabolome test are performed. Results show that external SS has significant influence on the related gene expression level of flavonoids synthesis ways of Gingko, the FD can significantly induce gene expressions as CHS, FLS, FOMT, PAL, MYB1 and MYB2, and RA can significantly induce gene expressions as FOMT, MYB1 and MYB2. Compared with the control group, FA selenium application can help to accumulation of flavonoids, flavonols, flavonoids-C and isoflavones, especially quercetin and kaempferol that had a remarkable increase. This proved that a proper concentration of inorganic SS could promote the synthesis and accumulation of flavonoids in Gingko. qRT-PCR analysis also depicts that leaves treatment of sodium selenite can remarkably enhance the gene expression of CHS, FLS, FOMT and PAL, and RA selenium application can induce the gene expression of FLS and FOMT, but restrain the gene expression of CHS and PAL. Through the ways of FD and RA selenium application, this paper basically studied the regulatory effect of SS on ginkgo flavonoids synthesis and has laid a theoretical basis to improve flavonoids content in Ginkgo leaves through cultivation control means
Determination of Camellia oleifera Abel. Germplasm Resources of Genetic Diversity in China using ISSR Markers
Camellia oleifera is one of the four woody oil plants in the world, which is widely cultivated in South China. To examine the genetic diversity of C. oleifera in China, the diversity and genetic relationships among and within major populations of 109 varieties of C. oleifera were analyzed using ISSR markers. Twenty-three ISSR primers out of 49 primers yielded approximately 487 legible bands. A total of 335 of these bands were polymorphic markers, and the ratio of polymorphism was 68.86%. From the results, Zhejiang province showed the highest populations genetic diversity (H value 0.18), while Guangxi population showed the lowest genetic diversity (H 0.0851). Base on the bands, the genetic similarity coefficient ranged from 0.61 to 0.93 using NTSYS2.10e software. When coefficient was 0.75, 109 cultivars were divided into 11 categories and categories I contain 79 varieties by UPGMA cluster analysis. The test varieties divided into 7 sub-groups when categories were 0.75, which show a close genetic relationship. Results advised that Hunan is the main producing area of C. oleifera, with enriched C. oleifera variety and complex topography, and therefore has a high genetic diversity. Meanwhile, the main varieties of C. oleifera in Hubei are imported from Hunan, which results in fewer varieties and reduces the genetic diversity of C. oleifera. The ISSR profiles can improve C. oleifera germplasm management and provide potential determine correlations between different varieties and its distribution in different province
Alterations in regional homogeneity of resting-state brain activity in patients with major depressive disorder screening positive on the 32-item hypomania checklist (HCL-32)
Background:Bipolar disorder (BD) is difficult to diagnose in the early stages of the illness, with the most frequent misdiagnosis being major depressive disorder (MDD). We aimed to use a regional homogeneity (ReHo) approach with resting-state functional magnetic resonance imaging (rs-fMRI) to investigate the features of spontaneous brain activity in MDD patients screening positive on the 32-item Hypomania Checklist (HCL-32).Methods:Nineteen MDD patients screening positive (HCL-32(+); 9 males; 24.9 ± 5.7 years) and 18 patients screening negative (HCL-32(-); 9 males; 27.1 ± 6.7 years), together with 24 healthy controls (HC; 11 males; 26.4 ± 3.9 years) were studied. ReHo maps were compared and an receiver operating characteristic (ROC) analysis was conducted to confirm the utility of the identified ReHo differences in classifying the patients. Results The MDD versus HC showed different ReHo in many brain areas, especially in the frontal and parietal cortex. The HCL-32(+) versus HCL-32(-) showed significant increase of ReHo in the right medial superior frontal cortex, left inferior parietal cortex and middle/inferior temporal cortex, and decrease of ReHo in the left postcentral cortex and cerebellum. ROC analysis showed good sensitivity and specificity for distinguishing these two subgroups of MDD. Limitations Recruited patients were all on antidepressants and standard mania rating scales were not used to assess their hypomanic symptoms. Conclusions:The rs-fMRI measurement of ReHo in distributed brain regions may be putative biomarkers which could differentiate subthreshold BD from MDD
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