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BACKGROUND: The formation and domestication of ornamental traits are influenced by various aspects, such as the recognition of esthetic values and cultural traditions. Camellia japonica is widely appreciated and domesticated around the world mainly due to its rich variations in ornamental traits. Ornamental camellias have a diverse range of resources, including different bud variations from Camellia spp. as well as inter- and intra- specific hybridization. Despite research on the formation of ornamental traits, a basic understanding of their genetics and genomics is still lacking. RESULTS: Here, we report the chromosomal-level reference genome of C. japonica through combining multiple DNA-sequencing technologies and obtain a high-density genetic linkage map of 4255 markers by sequencing 98 interspecific F1 hybrids between C. japonica and C. chekiangoleosa. We identify two whole-genome duplication events in C. japonica: one is a shared ancient γ event, and the other is revealed to be specific to genus Camellia. Based on the micro-collinearity analysis, we find large-scale segmental duplication of chromosome 8, resulting to two copies of the AGAMOUS loci, which may play a key role in the domestication of floral shapes. To explore the regulatory mechanisms of seasonal flowering, we have analyzed year-round gene expression patterns of C. japonica and C. azalea-a sister plant of continuous flowering that has been widely used for cross breeding. Through comparative analyses of gene co-expression networks and annual gene expression patterns, we show that annual expression rhythms of some important regulators of seasonal growth and development, including GIGANTEA and CONSTANS of the photoperiod pathway, have been disrupted in C. azalea. Furthermore, we reveal that the distinctive expression patterns of FLOWERING LOCUS T can be correlated with the seasonal activities of flowering and flushing. We demonstrate that the regulatory module involved in GIGANTEA, CONSTANS, and FLOWERING LOCUS T is central to achieve seasonality. CONCLUSIONS: Through the genomic and comparative genomics characterizations of ornamental Camellia spp., we propose that duplication of chromosomal segments as well as the establishment of gene expression patterns has played a key role in the formation of ornamental traits (e.g., flower shape, flowering time). This work provides a valuable genomic platform for understanding the molecular basis of ornamental traits.
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Camellia , Estaciones del Año , Camellia/genética , Fitomejoramiento , Genómica , Flores/genética , Expresión Génica , Regulación de la Expresión Génica de las PlantasRESUMEN
The plant MADS-box transcription factor family is a major regulator of plant flower development and reproduction, and the AGAMOUS-LIKE11/SEEDSTICK (AGL11/STK) subfamily plays conserved functions in the seed development of flowering plants. Camellia japonica is a world-famous ornamental flower, and its seed kernels are rich in highly valuable fatty acids. Seed abortion has been found to be common in C. japonica, but little is known about how it is regulated during seed development. In this study, we performed a genome-wide analysis of the MADS-box gene the in C. japonica genome and identified 126 MADS-box genes. Through gene expression profiling in various tissue types, we revealed the C/D-class MADS-box genes were preferentially expressed in seed-related tissues. We identified the AGL11/STK-like gene, CjSTK, and showed that it contained a typical STK motif and exclusively expressed during seed development. We found a significant increase in the CjSTK expression level in aborted seeds compared with normally developing seeds. Furthermore, overexpression of CjSTK in Arabidopsis thaliana caused shorter pods and smaller seeds. Taken together, we concluded that the fine regulation of the CjSTK expression at different stages of seed development is critical for ovule formation and seed abortion in C. japonica. The present study provides evidence revealing the regulation of seed development in Camellia.
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Camellia , Regulación de la Expresión Génica de las Plantas , Proteínas de Dominio MADS , Proteínas de Plantas , Semillas , Camellia/genética , Camellia/metabolismo , Camellia/crecimiento & desarrollo , Semillas/genética , Semillas/crecimiento & desarrollo , Proteínas de Dominio MADS/genética , Proteínas de Dominio MADS/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia , Arabidopsis/genética , Arabidopsis/metabolismo , Perfilación de la Expresión Génica , Familia de Multigenes , Genoma de Planta , Estudio de Asociación del Genoma CompletoRESUMEN
In trees, the annual cycling of active and dormant states in buds is closely regulated by environmental factors, which are of primary significance to their productivity and survival. It has been found that the parallel or convergent evolution of molecular pathways that respond to day length or temperature can lead to the establishment of conserved periodic gene expression patterns. In recent years, it has been shown in many woody plants that change in annual rhythmic patterns of gene expression may underpin the adaptive evolution in forest trees. In this review, we summarize the progress on the molecular mechanisms of seasonal regulation on the processes of shoot growth, bud dormancy, and bud break in response to day length and temperature factors. We focus on seasonal expression patterns of genes involved in dormancy and their associated epigenetic modifications; the seasonal changes in the extent of modifications, such as DNA methylation, histone acetylation, and histone methylation, at dormancy-associated loci have been revealed for their actions on gene regulation. In addition, we provide an outlook on the direction of research on the annual cycle of tree growth under climate change.
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Histonas , Árboles , Árboles/fisiología , Estaciones del Año , Histonas/genética , Metilación de ADN , Expresión Génica , Regulación de la Expresión Génica de las PlantasRESUMEN
Flower color is a trait that affects the ornamental value of a plant. Camellia sasanqua is a horticultural plant with rich flower color, but little is known about the regulatory mechanism of color diversity in this plant. Here, the anthocyanin profile of 20 C. sasanqua cultivars revealed and quantified 11 anthocyanin derivatives (five delphinidin-based and six cyanidin-based anthocyanins) for the first time. Cyanidin-3-O-(6-O-(E)-p-coumaroyl)-glucoside was the main contributor to flower base color, and the accumulation of cyanidin and delphinidin derivatives differed in the petals. To further explore the molecular mechanism of color divergence, a transcriptome analysis was performed using C. sasanqua cultivars 'YingYueYe', 'WanXia', 'XueYueHua', and'XiaoMeiGui'. The co-expression network related to differences in delphinidin and cyanidin derivatives accumulation was identified. Eleven candidate genes encoding key enzymes (e.g., F3H, F3'H, and ANS) were involved in anthocyanin biosynthesis. Moreover, 27 transcription factors were screened as regulators of the two types of accumulating anthocyanins. The association was suggested by correlation analysis between the expression levels of the candidate genes and the different camellia cultivars. We concluded that cyanidin and delphinidin derivatives are the major drivers of color diversity in C. sasanqua. This finding provides valuable resources for the study of flower color in C. sasanqua and lays a foundation for genetic modification of anthocyanin biosynthesis.
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Camellia , Camellia/genética , Camellia/metabolismo , Antocianinas , Perfilación de la Expresión Génica , Flores/genética , Pigmentación/genética , Transcriptoma , Regulación de la Expresión Génica de las PlantasRESUMEN
The exact pathogenesis of epilepsy, one of the most common and devastating diseases of the nervous system, is not fully understood. Syntaxin7 (STX7) is a member of the SNARE superfamily, which mediates membrane fusion events in all cells. However, the role STX7 plays in epilepsy remains unclear. Therefore, this study investigates the role of STX7 in epilepsy. Our study found that the expression of STX7 was reduced in the epileptic brain and that overexpression of STX7 decreased the susceptibility to epileptic seizures and alleviated epileptic activity in a kainic acid-induced model and pentylenetetrazole-induced kindling model of epilepsy, whereas the downregulation of STX7 showed opposite effects. Whole-cell patch-clamp recordings showed that STX7 does not affect the intrinsic excitability of neurons, but rather the excitation/inhibition ratio mediated by affecting the release of presynaptic γ-aminobutyric acid neurotransmitters. Transmission electron microscopy results showed that STX7 did not affect the density of inhibitory synapses but could affect the density of inhibitory vesicles. Taken together, these results reveal a previously unknown function of STX7 in epilepsy and suggest that STX7 may serve as a novel target for epilepsy therapy.
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Epilepsia , Humanos , Proteínas Portadoras , Epilepsia/metabolismo , Neuronas/metabolismo , Proteínas Qa-SNARE/metabolismo , Convulsiones/metabolismo , Animales , RatonesRESUMEN
A superior semiconductor material with efficient charge separation and easy reuse could be a promising route for efficient photocatalytic hydrogen evolution and pollutant degradation. AgVO3 is one of the best visible light active materials which has attracted much attention for several biological and environmental applications. In the aim of enhancing its stability and recyclability a novel AgVO3/rGO/CuFe2O4 heterojunction was prepared by hydrothermal method for hydrogen generation (H2) and 4-nitrophenol (4-NP) degradation as well. The composite was well characterized by XRD, SEM, HR-TEM, XPS and VSM. The morphological images suggested the rod shaped AgVO3 and irregular shaped CuFe2O4 are unevenly distributed on reduced graphene oxide (rGO) layers. The hydrogen evolution results indicated that the composite showed around 8.937 mmol g-1h-1 of H2 generation which was â¼2.3 times and â¼9.2 times higher than pure AgVO3 (3.895 mmol g-1h-1) and CuFe2O4 (0.96 mmol g-1h-1) respectively. The 4-NP degradation efficiency of the prepared composite was observed as 94.7% (k = 0.01841 min-1) which is much higher than the AgVO3 (66.3%) and CuFe2O4 (38.2%) after 4 h of irradiation. The higher efficiency could be attributed to the heterojunction formation and faster charge separation. The radical trapping results indicated that the â¢OH, O2â¢- and photogenerated h+ are the main species responsible for efficient activity. The AgVO3/rGO/CuFe2O4 heterojunction showed 49.6 emu/g of saturation magnetization and confirms that it could be easily separated with an external magnet, and showed 85.3% of degradation efficiency even after 6 recycles which indicated its higher stability and recyclability. Thus, our study provides new insight into hydrogen generation and phenol degradation using AgVO3 based recyclable composites.
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Grafito , Hidrógeno , Luz , CatálisisRESUMEN
BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is a rare and life-threatening disorder characterized by systemic inflammation and organ failure as a result of dysregulated immune cell activation. HLH can be induced by a variety of factors including infection, tumours and autoimmune disease and can also occur in patients following solid organ transplantation. Occurrence of HLH and lupus nephritis (LN) successively within a short period of time after renal transplantation is uncommon. CASE PRESENTATION: We described an 11-year-old female post-transplant patient who presented with hemocytopenia, fever, elevated serum ferritin, splenomegaly, hyperlipidemia, and hypofibrinemia, and was clinically diagnosed with HLH. After comprehensive treatment with corticosteroids, intravenous immunoglobulin (IVIG), and reducing immunosuppressants, her condition improved, but then hematuria ensued. The transplant kidney biopsy showed LN. She was treated with hydroxychloroquine and methylprednisolone while intensive immunosuppressive agents were given. She has remained in remission for two years until now. CONCLUSIONS: The main inducing factors of HLH should be identified as early as possible, and accurate treatment plans should be taken. The long-course IVIG regimen may be one of the effective treatments for virus-induced HLH. After remission of HLH, we need to be alert to the recurrence of autoimmune diseases in patients with underlying diseases, and timely increase immunosuppressants.
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Trasplante de Riñón , Nefritis Lúpica , Linfohistiocitosis Hemofagocítica , Virosis , Humanos , Niño , Femenino , Linfohistiocitosis Hemofagocítica/diagnóstico , Linfohistiocitosis Hemofagocítica/tratamiento farmacológico , Linfohistiocitosis Hemofagocítica/etiología , Trasplante de Riñón/efectos adversos , Nefritis Lúpica/complicaciones , Nefritis Lúpica/diagnóstico , Nefritis Lúpica/tratamiento farmacológico , Inmunoglobulinas Intravenosas/uso terapéutico , Inmunosupresores/uso terapéutico , Riñón , Virosis/complicacionesRESUMEN
Drought has severe effects on plant growth, forest productivity, and survival throughout the world. Understanding the molecular regulation of drought resistance in forest trees can enable effective strategic engineering of novel drought-resistant genotypes of tree species. In this study, we identified a gene, PtrVCS2, encoding a zinc finger (ZF) protein of the ZF-homeodomain transcription factor in Populus trichocarpa (Black Cottonwood) Torr. & A. Gray. ex Hook. Overexpression of PtrVCS2 (OE-PtrVCS2) in P. trichocarpa resulted in reduced growth, a higher proportion of smaller stem vessels, and strong drought-resistance phenotypes. Stomatal movement experiments revealed that the OE-PtrVCS2 transgenics showed lower stomata apertures than wild-type plants under drought conditions. RNA-seq analysis of the OE-PtrVCS2 transgenics showed that PtrVCS2 regulates the expression of multiple genes involved in regulation of stomatal opening and closing, particularly the PtrSULTR3;1-1 gene, and several genes related to cell wall biosynthesis, such as PtrFLA11-12 and PtrPR3-3. Moreover, we found that the water use efficiency of the OE-PtrVCS2 transgenic plants was consistently higher than that of wild type plants when subjected to chronic drought stress. Taken together, our results suggest that PtrVCS2 plays a positive role in improving drought adaptability and resistance in P. trichocarpa.
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Estomas de Plantas , Populus , Estomas de Plantas/metabolismo , Resistencia a la Sequía , Populus/genética , Agua/metabolismo , Sequías , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente/metabolismo , Estrés Fisiológico/genética , Proteínas de Plantas/genéticaRESUMEN
BACKGROUND: The cultivated Camellia sasanqua forms a divergent double flower pattern, and the stamen petaloid is a vital factor in the phenomenon. However, the regulation mechanism remains largely unclear. RESULTS: Here, a comprehensive comparative transcriptome analysis of the wild-type, "semi-double", "peony double", and "rose double" was performed. The cluster analysis of global gene expression level showed petal and stamen difficulty separable in double flower. The crucial pathway and genes related to double flower patterns regulation were identified by pairwise comparisons and weighted gene coexpression network (WGCNA). Divergent genes expression, such as AUX1 and AHP, are involved in plant hormone signaling and photosynthesis, and secondary metabolites play an important role. Notably, the diversity of a petal-specific model exhibits a similar molecular signature to the stamen, containing extensin protein and PSBO1, supporting the stamen petaloid point. Moreover, the expansion of class A gene activity influenced the double flower formation, showing that the key function of gene expression was probably demolished. CONCLUSIONS: Overall, this work confirmed the ABCE model and provided new insights for elucidating the molecular signature of double formation.
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Camellia , Transcriptoma , Camellia/genética , Flores/genética , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas/genética , Reguladores del Crecimiento de las Plantas/metabolismoRESUMEN
The rise of the Tubo Kingdom is considered as the key period for the formation of modern groups on the Tibetan Plateau. The ethnic origin of the residents of the Tubo Kingdom is quite complex, and their genetic structure remains unclear. The tombs of the Tubo Kingdom period in Dulan County, Qinghai Province, dating back to the seventh century, are considered to be the remains left by Tubo conquerors or the Tuyuhun people dominated by the Tubo Kingdom. The human remains of these tombs are ideal materials for studying the population dynamics in the Tubo Kingdom. In this paper, we analyzed the genome-wide data of eight remains from these tombs by shotgun sequencing and multiplex PCR panels and compared the results with data of available ancient and modern populations across East Asia. Genetic continuity between ancient Dulan people with ancient Xianbei tribes in Northeast Asia, ancient settlers on the Tibetan Plateau, and modern Tibeto-Burman populations was found. Surprisingly, one out of eight individuals showed typical genetic features of populations from Central Asia. In summary, the genetic diversity of ancient Dulan people and their affiliations with other populations provide an example of the complex origin of the residents in the Tubo Kingdom and their long-distance connection with populations in a vast geographic region across ancient Asia.
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ADN Antiguo , Genética de Población , Humanos , Tibet , Pueblo Asiatico/genética , Etnicidad , Variación Genética/genéticaRESUMEN
Background: Flower senescence is the last stage of flower development and affects the ornamental and economic value of flower plants. There is still less known on flower senescence of the ornamental plant Camellia lutchuensis, a precious species of Camellia with significant commercial application value. Methods: Transcriptome sequencing was used to investigate the flower senescence in five developmental stages of C. lutchuensis. Results: By Illumina HiSeq sequencing, we generated approximately 101.16 Gb clean data and 46649 differentially expressed unigenes. Based on the different expression pattern, differentially expressed unigenes were classified into 10 Sub Class. And Sub Class 9 including 8252 unigenes, was highly expressed in the flower senescent stage, suggesting it had a potential regulatory relationship of flower senescence. First, we found that ethylene biosynthesis genes ACSs, ACOs, receptor ETR genes and signaling genes EINs, ERFs all upregulated during flower senescence, suggesting ethylene might play a key role in the flower senescence of C. lutchuensis. Furthermore, reactive oxygen species (ROS) production related genes peroxidase (POD), lipase (LIP), polyphenoloxidase (PPO), and ROS scavenging related genes glutathione S-transferase (GST), glutathione reductase (GR) and superoxide dismutase (SOD) were induced in senescent stage, suggesting ROS might be involved in the flower senescence. Besides, the expression of monoterpenoid and isoflavonoid biosynthesis genes, transcription factors (WRKY, NAC, MYB and C2H2 ), senescence-associated gene SAG20 also were increased during flower senescence. Conclusion: In C. lutchuensis, ethylene pathway might be the key to regulate flower senescence, and ROS signal might play a role in the flower senescence.
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BACKGROUND: Feed efficiency is one of the key determinants of beef industry profitability and sustainability. However, the cellular and molecular background behind feed efficiency is largely unknown. This study combines imputed whole genome DNA variants and 31 plasma metabolites to dissect genes and biological functions/processes that are associated with residual feed intake (RFI) and its component traits including daily dry matter intake (DMI), average daily gain (ADG), and metabolic body weight (MWT) in beef cattle. RESULTS: Regression analyses between feed efficiency traits and plasma metabolites in a population of 493 crossbred beef cattle identified 5 (L-valine, lysine, L-tyrosine, L-isoleucine, and L-leucine), 4 (lysine, L-lactic acid, L-tyrosine, and choline), 1 (citric acid), and 4 (L-glutamine, glycine, citric acid, and dimethyl sulfone) plasma metabolites associated with RFI, DMI, ADG, and MWT (P-value < 0.1), respectively. Combining the results of metabolome-genome wide association studies using 10,488,742 imputed SNPs, 40, 66, 15, and 40 unique candidate genes were identified as associated with RFI, DMI, ADG, and MWT (P-value < 1 × 10-5), respectively. These candidate genes were found to be involved in some key metabolic processes including metabolism of lipids, molecular transportation, cellular function and maintenance, cell morphology and biochemistry of small molecules. CONCLUSIONS: This study identified metabolites, candidate genes and enriched biological functions/processes associated with RFI and its component traits through the integrative analyses of metabolites with phenotypic traits and DNA variants. Our findings could enhance the understanding of biochemical mechanisms of feed efficiency traits and could lead to improvement of genomic prediction accuracy via incorporating metabolite data.
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Alimentación Animal , Estudio de Asociación del Genoma Completo , Alimentación Animal/análisis , Animales , Bovinos , Ingestión de Alimentos , Genoma , FenotipoRESUMEN
BACKGROUND: Genome-wide change of polyadenylation (polyA) sites (also known as alternative polyadenylation, APA) is emerging as an important strategy of gene regulation in response to stress in plants. But little is known in woody perennials that are persistently dealing with multiple abiotic stresses. RESULTS: Here, we performed a genome-wide profiling of polyadenylation sites under heat and cold treatments in Populus trichocarpa. Through a comprehensive analysis of polyA tail sequences, we identified 25,919 polyA-site clusters (PACs), and revealed 3429 and 3139 genes shifted polyA sites under heat and cold stresses respectively. We found that a small proportion of genes possessed APA that affected the open reading frames; and some shifts were commonly identified. Functional analysis of genes displaying shifted polyA tails suggested that pathways related to RNA metabolism were linked to regulate the APA events under both heat and cold stresses. Interestingly, we found that the heat stress induced a significantly more antisense PACs comparing to cold and control conditions. Furthermore, we showed that a unique cis-element (AAAAAA) was predominately enriched downstream of PACs in P. trichocarpa genes; and this sequence signal was only absent in shifted PACs under the heat condition, indicating a distinct APA mechanism responsive to heat tolerance. CONCLUSIONS: This work provides a comprehensive picture of global polyadenylation patterns in response to temperatures stresses in trees. We show that the frequent change of polyA tail is a potential mechanism of gene regulation responsive to stress, which are associated with distinctive sequence signatures.
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Poliadenilación , Populus , Regulación de la Expresión Génica de las Plantas , Respuesta al Choque Térmico , Populus/genética , Estrés Fisiológico/genética , TemperaturaRESUMEN
MAIN CONCLUSION: CcBLH6 is a bell-like homeodomain-containing transcription factor that plays an important role of lignin biosynthesis in the control of fruit lignification pattern in Camellia chekiangoleosa. The fruit of Camellia chekiangoleosa has a unique lignification pattern that features with a thick pericarp containing a low level of lignification. Yet the fruit lignification pattern and the regulatory network of responsible gene transcription are poorly understood. Here, we characterized a bell-like homeodomain-containing (BLH) transcription factor from C. chekiangoleosa, CcBLH6, in the control of fruit lignification. CcBLH6 expression was highly correlated with the unique lignification pattern during fruit development. The ectopic expression of CcBLH6 promoted the lignification process of stem and root in Arabidopsis. We found that expression of genes related to lignin biosynthesis and its transcriptional regulation was altered in transgenic lines. In a Camellia callus-transformation system, overexpression of CcBLH6 greatly enhanced the expression of genes related to lignin biosynthesis and its transcriptional regulation was altered in transgenic lines. In the callus-transformation system, overexpression of CcBLH6 greatly enhanced the lignification of parenchymal cells, and the regulation of several genes involved in lignin accumulation was largely consistent between Arabidopsis and Camellia. Our study reveals a positive role of CcBLH6 in the regulation of lignin biosynthesis during fruit lignification in Camellia.
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Camellia/genética , Camellia/metabolismo , Frutas/genética , Frutas/metabolismo , Proteínas de Homeodominio/metabolismo , Lignina/metabolismo , Factores de Transcripción/química , Factores de Transcripción/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las PlantasRESUMEN
PURPOSE: In this work, the safety, biodistribution, and radiation dosimetry of large neutral amino acid transporter type-1 (LAT-1) targeting PET tracer 18F-trifluorobborate-derived tyrosine (denoted as 18F-FBY) has been investigated. It is designed as a first-in-human study in healthy volunteers and to assay LAT-1 expression level in glioma patients. METHODS: Six healthy volunteers (3 M, 3 F) underwent whole-body PET acquisitions at multiple time points after bolus injection of 18F-FBY. Regions of interest (ROIs) were mapped manually on major organs, and then the time-activity curves (TACs) were obtained. Dosimetry was calculated with the OLINDA/EXM software. Thirteen patients who were suspected of glioma were scanned with PET/CT at 30 min after 18F-FBY injection. Within 7 days after PET/CT, the tumor was removed surgically, and LAT-1 immunohistochemical staining for LAT-1 was performed on tumor samples and correlated with 18F-FBY PET imaging. RESULTS: 18F-FBY was well tolerated by all healthy volunteers, and no adverse symptoms were observed or reported. 18F-FBY is rapidly cleared from the blood circulation and excreted mainly through the kidneys and urinary tract. The effective dose (ED) was 0.0039 ± 0.0006 mSv/MBq. In 14 surgical confirmed gliomas (one of the patiens had two gliomas), 18F-FBY uptake increased consistently with tumor grade, with maximum standard uptake values (SUVmax) of 0.28 ± 0.14 and 2.84 ± 0.46 and tumor-to-normal contralateral activity (T/N) ratio of 2.30 ± 1.26 and 24.56 ± 6.32 in low- and high-grade tumors, respectively. In addition to the significant difference in the uptakes between low- and high-grade gliomas (P < 0.001), the immunohistochemical staining confirmed the positive correlations between the SUVmax, LAT-1 expression (r2 = 0.80, P < 0.001), and Ki-67 labeling index (r2 = 0.79, P < 0.001). CONCLUSION: 18F-FBY is a PET tracer with favorable dosimetry profile and pharmacokinetics. It has the potential to assay LAT-1 expression in glioma patients and may provide imaging guidance for further boron neutron capture therapy of gliomas. TRIAL REGISTRATION: clinicaltrials.gov (NCT03980431).
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Glioma , Tomografía Computarizada por Tomografía de Emisión de Positrones , Glioma/diagnóstico por imagen , Voluntarios Sanos , Humanos , Tomografía de Emisión de Positrones , Radiometría , Distribución TisularRESUMEN
PD-1/PD-L1 is an important pathway in immunotherapy and a high PD-L1 expression level in tumor tissues is an essential prerequisite for PD-1/PD-L1 blocking-based therapy. The PD-L1 expression level in tumor tissue sections is currently detected via immunohistochemistry (IHC) using anti-PD-L1 antibodies from various resources, which has the disadvantage of inconsistent results. As synthetic affinity ligands, aptamers have good batch-to-batch consistency and have been demonstrated to have great potential for use in biomedical applications. In this study, we isolated PD-L1 aptamers using a combination method, named Modular-SELEX (systematic evolution of ligands by exponential enrichment), which includes three sequentially performed modules: the affinity module, the specificity module, and the compatibility module. Three rounds of magnetic crosslinking precipitation (MCP)-SELEX, three rounds of Capture-SELEX, and two rounds of Tissue-SELEX were respectively performed in the corresponding three modules to significantly and efficiently improve the native affinity, specificity, and compatibility of the enriched library. The isolated aptamer Clon-3 had nanomolar binding affinity, as determined via both homogeneous and PD-L1 immobilized affinity assays. Clon-3 could be used to recognize various cancer cells with distinct PD-L1 expression levels using flow cytometry. The PD-L1 expression levels in normal human tonsils (the gold standard for anti-PD-L1 antibody) and non-small cell lung cancer tissue sections stained using Cy5.5-labeled Clon-3 were also successfully imaged using a confocal microscope. The fluorescence intensities of the tissue sections were in good agreement with their actual PD-L1 expression levels as confirmed via IHC.
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Aptámeros de Nucleótidos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Antígeno B7-H1 , Humanos , Técnica SELEX de Producción de AptámerosRESUMEN
Camellia nitidissima Chi. is an ornamental plant of the genus Camellia L. Its flowers contain a lot of flavonoids and polyphenols. Flavonoid 3'-hydroxylase (F3'H) plays an important role in the synthesis of flavonoids, polyphenols and anthocyanins. We used PCR amplification, quantitative PCR, High-performance liquid chromatography, subcellular localization, and agrobacterium-mediated leaf disk method to study the the function of CnF3'H. The full length of CnF3'H was 1859 bp (GenBank code: HQ290518.1), with an open reading frame of 1577 bp, and encoded 518 amino acid. A phylogenetic tree analysis showed that CnF3'H was closely related to Camellia sinensis L. and C. sinensis cultivar Zhonghuang. CnF3'H was expressed in flowers, leaves, fruits, sepals, petals and stamens of C. nitidissima, and during the flowering process the expression level in flower decreased initially and then increased. CnF3'H expression was significantly positive correlated with polyphenol contents in C. nitidissima. A CnF3'H-EGFP expression vector was constructed to do the subcellular localization, we found that CnF3'H was obviously localized in the nuclear envelope and cytomembrane. In transgenic tobacco flowers, the total polyphenol content and various polyphenol constituents were significantly increased with high CnF3'H expression level, while total flavonoid contents and some flavonol constituents were increased slightly. These findings suggest that CnF3'H promotes the synthesis of polyphenols better than flavonoids.
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Camellia/metabolismo , Sistema Enzimático del Citocromo P-450/fisiología , Antocianinas/metabolismo , China , Cromatografía Líquida de Alta Presión/métodos , Sistema Enzimático del Citocromo P-450/metabolismo , Flavonoides/metabolismo , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Oxigenasas de Función Mixta/metabolismo , Filogenia , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Polifenoles/metabolismoRESUMEN
Valproic acid (VPA), or sodium valproate, is a commonly used medication for seizure disorders, migraines, and mental illness. Although VPA is relatively safe, it still has several adverse effects; among these, VPA-induced encephalopathy is the most serious. Valproic acid-induced encephalopathy mainly manifests as acute or subacute encephalopathy and has been associated with hyperammonemia, L-carnitine deficiency, and urea cycle enzyme dysfunction. Delayed identification of VPA-induced encephalopathy could be potentially fatal. Here, we perform an extensive review of relevant literature pertaining to VPA-induced encephalopathy, including its epidemiology, clinical features, possible pathophysiology, risk factors, diagnosis, and treatment.
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Encefalopatías , Hiperamonemia , Anticonvulsivantes/uso terapéutico , Encefalopatías/tratamiento farmacológico , Humanos , Hiperamonemia/tratamiento farmacológico , Factores de Riesgo , Ácido ValproicoRESUMEN
Flavonoids are an important class of secondary metabolites widely found in plants, contributing to plant growth and development and having prominent applications in food and medicine. The biosynthesis of flavonoids has long been the focus of intense research in plant biology. Flavonoids are derived from the phenylpropanoid metabolic pathway, and have a basic structure that comprises a C15 benzene ring structure of C6-C3-C6. Over recent decades, a considerable number of studies have been directed at elucidating the mechanisms involved in flavonoid biosynthesis in plants. In this review, we systematically summarize the flavonoid biosynthetic pathway. We further assemble an exhaustive map of flavonoid biosynthesis in plants comprising eight branches (stilbene, aurone, flavone, isoflavone, flavonol, phlobaphene, proanthocyanidin, and anthocyanin biosynthesis) and four important intermediate metabolites (chalcone, flavanone, dihydroflavonol, and leucoanthocyanidin). This review affords a comprehensive overview of the current knowledge regarding flavonoid biosynthesis, and provides the theoretical basis for further elucidating the pathways involved in the biosynthesis of flavonoids, which will aid in better understanding their functions and potential uses.
Asunto(s)
Vías Biosintéticas , Flavonoides/biosíntesis , Regulación de la Expresión Génica de las Plantas , Redes Reguladoras de Genes , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Proteínas de Plantas/genéticaRESUMEN
In this paper, Eichhornia Crassipes stems were used as biomass feedstock, and Fe2+ was used as the precursor solution to prepare Fe3O4-modified magnetic mesoporous biochar (Fe3O4@BC). By using Box-Behnken design (BBD) response surface methodology, the influences of three preparation parameters (X1 = Fe2+ concentration, X2 = pyrolysis temperature and X3 = pyrolysis time) on the adsorption of methyl orange (MO) by Fe3O4@BC were investigated, and a reliable response surface model was constructed. The results show that X1X2 and X1X3 have a significant influence on the adsorption of MO by Fe3O4@BC. The surface area and pore volume of Fe3O4@BC are controlled by all preparation parameters. The increase of pyrolysis time will significantly reduce the -OH on the surface of Fe3O4@BC and weaken its MO adsorption capacity. Through the numerical optimization of the constructed model, the optimal preparation parameters of Fe3O4@BC can be obtained as follows: Fe2+ concentration = 0.27 mol/L, pyrolysis temperature = 405 °C, and pyrolysis time = 3.2 h. The adsorption experiment shows that the adsorption of Fe3O4@BC to MO is a spontaneous exothermic process, and the adsorption capacity is maximum when pH = 4. The adsorption kinetics and adsorption isotherms of Fe3O4@BC to MO conform to the pseudo-second-order kinetics and Sips model, respectively. Mechanism analysis shows that electrostatic interaction and H bond formation are the main forces for Fe3O4@BC to adsorb MO. This research not only realizes a new way of resource utilization of Eichhornia Crassipes biomass but also enriches the preparation research of magnetic biochar.