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1.
PLoS Biol ; 22(1): e3002375, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38236815

RESUMEN

Detecting imminent collisions is essential for survival. Here, we used high-resolution fMRI at 7 Tesla to investigate the role of attention and consciousness for detecting collision trajectory in human subcortical pathways. Healthy participants can precisely discriminate collision from near-miss trajectory of an approaching object, with pupil size change reflecting collision sensitivity. Subcortical pathways from the superior colliculus (SC) to the ventromedial pulvinar (vmPul) and ventral tegmental area (VTA) exhibited collision-sensitive responses even when participants were not paying attention to the looming stimuli. For hemianopic patients with unilateral lesions of the geniculostriate pathway, the ipsilesional SC and VTA showed significant activation to collision stimuli in their scotoma. Furthermore, stronger SC responses predicted better behavioral performance in collision detection even in the absence of awareness. Therefore, human tectofugal pathways could automatically detect collision trajectories without the observers' attention to and awareness of looming stimuli, supporting "blindsight" detection of impending visual threats.


Asunto(s)
Percepción de Movimiento , Pulvinar , Humanos , Percepción de Movimiento/fisiología , Colículos Superiores/fisiología , Imagen por Resonancia Magnética , Pulvinar/diagnóstico por imagen , Estimulación Luminosa , Vías Visuales/fisiología
2.
Plant Biotechnol J ; 22(8): 2364-2376, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38683692

RESUMEN

Glomerella leaf spot (GLS), caused by the fungus Colletotrichum fructicola, is considered one of the most destructive diseases affecting apples. The VQ-WRKY complex plays a crucial role in the response of plants to biotic stresses. However, our understanding of the defensive role of the VQ-WRKY complex on woody plants, particularly apples, under biotic stress, remains limited. In this study, we elucidated the molecular mechanisms underlying the defensive role of the apple MdVQ37-MdWRKY100 module in response to GLS infection. The overexpression of MdWRKY100 enhanced resistance to C. fructicola, whereas MdWRKY100 RNA interference in apple plants reduced resistance to C. fructicola by affecting salicylic acid (SA) content and the expression level of the CC-NBS-LRR resistance gene MdRPM1. DAP-seq, Y1H, EMSA, and RT-qPCR assays indicated that MdWRKY100 inhibited the expression of MdWRKY17, a positive regulatory factor gene of SA degradation, upregulated the expression of MdPAL1, a key enzyme gene of SA biosynthesis, and promoted MdRPM1 expression by directly binding to their promotors. Transient overexpression and silencing experiments showed that MdPAL1 and MdRPM1 positively regulated GLS resistance in apples. Furthermore, the overexpression of MdVQ37 increased the susceptibility to C. fructicola by reducing the SA content and expression level of MdRPM1. Additionally, MdVQ37 interacted with MdWRKY100, which repressed the transcriptional activity of MdWRKY100. In summary, these results revealed the molecular mechanism through which the apple MdVQ37-MdWRKY100 module responds to GLS infection by regulating SA content and MdRPM1 expression, providing novel insights into the involvement of the VQ-WRKY complex in plant pathogen defence responses.


Asunto(s)
Colletotrichum , Resistencia a la Enfermedad , Regulación de la Expresión Génica de las Plantas , Malus , Enfermedades de las Plantas , Proteínas de Plantas , Ácido Salicílico , Malus/microbiología , Malus/genética , Malus/metabolismo , Ácido Salicílico/metabolismo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Resistencia a la Enfermedad/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Colletotrichum/fisiología , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/microbiología , Hojas de la Planta/genética , Plantas Modificadas Genéticamente
3.
Luminescence ; 39(1): e4671, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38286599

RESUMEN

Copper is a critical element in both human and animal metabolic processes. Its role includes supporting connective tissue cross-linking, as well as iron and lipid metabolism; at the same time, copper is also a toxic heavy metal that can cause harm to both the environment and human health. Glutathione (GSH) is a tripeptide composed of glutamic acid, cysteine, and glycine combined with sulfhydryl groups. Its properties include acting as an antioxidant and facilitating integrative detoxification. GSH is present in both plant and animal cells and has a fundamental role in maintaining living organisms. GSH is the most abundant thiol antioxidant in the human body. It exists in reduced and oxidized forms within cells and provides significant biochemical functions, such as regulating vitamins such as vitamins D, E, and C, and facilitating detoxification. A fluorescent probe has been developed to detect copper ions selectively, sensitively, and rapidly. This report outlines the successful work on creating a peptide probe, TGN (TPE-Trp-Pro-Gly-Cln-His-NH2 ), with specific Cu2+ detection capabilities, and a significant fluorescence recovery occurred with the addition of GSH. This indicates that the probe can detect Cu2+ and GSH concurrently. The detection limit for Cu2+ in the buffer solution was 264 nM (R2 = 0.9992), and the detection limit for GSH using the TGN-Cu2+ complex was 919 nM (R2 = 0.9917). The probe exhibits high cell permeability and low biotoxicity that make it ideal for live cell imaging in biological conditions. This peptide probe has the capability to detect Cu2+ and GSH in biological cells.


Asunto(s)
Antioxidantes , Cobre , Animales , Humanos , Cobre/química , Ligandos , Glutatión , Péptidos/química , Colorantes Fluorescentes/química , Espectrometría de Fluorescencia/métodos , Vitaminas
4.
Pestic Biochem Physiol ; 201: 105874, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38685243

RESUMEN

In insects, chemosensory proteins (CSPs) play an important role in the perception of the external environment and have been widely used for protein-binding characterization. Riptortus pedestris has received increased attention as a potential cause of soybean staygreen syndrome in recent years. In this study, we found that RpedCSP4 expression in the antennae of adult R. pedestris increased with age, with no significant difference in expression level observed between males and females, as determined through quantitative real-time polymerase chain reaction (qRT-PCR). Subsequently, we investigated the ability of RpedCSP4 to bind various ligands (five aggregated pheromone components and 13 soybean volatiles) using a prokaryotic expression system and fluorescence competitive binding assays. We found that RpedCSP4 binds to three aggregated pheromone components of R. pedestris, namely, ((E)-2-hexenyl (Z)-3-hexenoate (E2Z3), (E)-2-hexenyl (E)-2-hexenoate (E2E2), and (E)-2-hexenyl hexenoate (E2HH)), and that its binding capacities are most stable under acidic condition. Finally, the structure and protein-ligand interactions of RpedCSP4 were further analyzed via homology modeling, molecular docking, and targeted mutagenesis experiments. The L29A mutant exhibited a loss of binding ability to these three aggregated pheromone components. Our results show that the olfactory function of RpedCSP4 provides new insights into the binding mechanism of RpedCSPs to aggregation pheromones and contributes to discover new target candidates that will provide a theoretical basis for future population control of R. pedestris.


Asunto(s)
Proteínas de Insectos , Feromonas , Animales , Feromonas/metabolismo , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Proteínas de Insectos/química , Masculino , Femenino , Unión Proteica , Heterópteros/metabolismo , Heterópteros/genética
5.
Int J Mol Sci ; 24(4)2023 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-36835052

RESUMEN

The breeding of salt-tolerant rootstock relies heavily on the availability of salt-tolerant Malus germplasm resources. The first step in developing salt-tolerant resources is to learn their molecular and metabolic underpinnings. Hydroponic seedlings of both ZM-4 (salt-tolerant resource) and M9T337 (salt-sensitive rootstock) were treated with a solution of 75 mM salinity. ZM-4's fresh weight increased, then decreased, and then increased again after being treated with NaCl, whereas M9T337's fresh weight continued to decrease. The results of transcriptome and metabolome after 0 h (CK) and 24 h of NaCl treatment showed that the leaves of ZM-4 had a higher content of flavonoids (phloretinm, naringenin-7-O-glucoside, kaempferol-3-O-galactoside, epiafzelechin, etc.) and the genes (CHI, CYP, FLS, LAR, and ANR) related to the flavonoid synthesis pathway showed up-regulation, suggesting a high antioxidant capacity. In addition to the high polyphenol content (L-phenylalanine, 5-O-p-coumaroyl quinic acid) and the high related gene expression (4CLL9 and SAT), the roots of ZM-4 exhibited a high osmotic adjustment ability. Under normal growing conditions, the roots of ZM-4 contained a higher content of some amino acids (L-proline, tran-4-hydroxy-L-prolin, L-glutamine, etc.) and sugars (D-fructose 6-phosphate, D-glucose 6-phosphate, etc.), and the genes (GLT1, BAM7, INV1, etc.) related to these two pathways were highly expressed. Furthermore, some amino acids (S-(methyl) glutathione, N-methyl-trans-4-hydroxy-L-proline, etc.) and sugars (D-sucrose, maltotriose, etc.) increased and genes (ALD1, BCAT1, AMY1.1, etc.) related to the pathways showed up-regulation under salt stress. This research provided theoretical support for the application of breeding salt-tolerant rootstocks by elucidating the molecular and metabolic mechanisms of salt tolerance during the early stages of salt treatment for ZM-4.


Asunto(s)
Malus , Tolerancia a la Sal , Estrés Fisiológico , Transcriptoma , Aminoácidos/metabolismo , Flavonoides/metabolismo , Regulación de la Expresión Génica de las Plantas , Malus/genética , Metaboloma , Fosfatos/metabolismo , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Tolerancia a la Sal/genética , Cloruro de Sodio/metabolismo , Estrés Fisiológico/genética
6.
Int J Mol Sci ; 24(1)2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36614250

RESUMEN

Apples are a major horticultural crop worldwide. Grafting techniques are widely utilized in apple production to keep the varieties pure. Interstocks are frequently used in Northern China to achieve intensive apple dwarfing cultivation. High-throughput sequencing was used to investigate differentially expressed genes in the phloem tissues of two different xenograft systems, M ('Gala'/'Mac 9'/Malus baccata (L.) Borkh.) and B ('Gala'/Malus baccata (L.) Borkh.). The results showed that dwarfing interstocks could significantly reduce the height and diameters of apple trees while have few effects on the growth of annual branches. The interstocks were found to regulate the expression of genes related to hormone metabolism and tree body control (GH3.9, PIN1, CKI1, ARP1, GA2ox1 and GA20ox1), these effects may attribute the dwarf characters for apple trees with interstocks. Besides, the interstocks reduce photosynthesis-related genes (MADH-ME4 and GAPC), promote carbon (C) metabolism gene expression (AATP1, GDH and PFK3), promote the expression of nitrogen (N)-metabolism-related genes (NRT2.7, NADH and GDH) in rootstocks, and improve the expression of genes related to secondary metabolism in scions (DX5, FPS1, TPS21 and SRG1). We also concluded that the interstocks acquired early blooming traits due to promotion of the expression of flowering genes in the scion (MOF1, FTIP7, AGL12 and AGL24). This study is a valuable resource regarding the molecular mechanisms of dwarf interstocks' influence on various biological processes and transplantation systems in both scions and rootstocks.


Asunto(s)
Malus , Humanos , Malus/metabolismo , Perfilación de la Expresión Génica , Fenotipo , China , Regulación de la Expresión Génica de las Plantas , Peptidilprolil Isomerasa de Interacción con NIMA/metabolismo
7.
Plant Biotechnol J ; 20(7): 1285-1297, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35258172

RESUMEN

Allele-specific expression (ASE) can lead to phenotypic diversity and evolution. However, the mechanisms regulating ASE are not well understood, particularly in woody perennial plants. In this study, we investigated ASE genes in the apple cultivar 'Royal Gala' (RG). A high quality chromosome-level genome was assembled using a homozygous tetra-haploid RG plant, derived from anther cultures. Using RNA-sequencing (RNA-seq) data from RG flower and fruit tissues, we identified 2091 ASE genes. Compared with the haploid genome of 'Golden Delicious' (GD), a parent of RG, we distinguished the genomic sequences between the two alleles of 817 ASE genes, and further identified allele-specific presence of a transposable element (TE) in the upstream region of 354 ASE genes. These included MYB110a that encodes a transcription factor regulating anthocyanin biosynthesis. Interestingly, another ASE gene, MYB10 also showed an allele-specific TE insertion and was identified using genome data of other apple cultivars. The presence of the TE insertion in both MYB genes was positively associated with ASE and anthocyanin accumulation in apple petals through analysis of 231 apple accessions, and thus underpins apple flower colour evolution. Our study demonstrated the importance of TEs in regulating ASE on a genome-wide scale and presents a novel method for rapid identification of ASE genes and their regulatory elements in plants.


Asunto(s)
Malus , Alelos , Antocianinas , Color , Elementos Transponibles de ADN , Flores/genética , Flores/metabolismo , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Genoma de Planta , Malus/metabolismo , Proteínas de Plantas/genética
8.
Int J Mol Sci ; 23(11)2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-35682639

RESUMEN

LncRNAs impart crucial effects on various biological processes, including biotic stress responses, abiotic stress responses, fertility and development. The apple tree is one of the four major fruit trees in the world. However, lncRNAs's roles in different tissues of apple are unknown. We identified the lncRNAs in five tissues of apples including the roots, phloem, leaves, flowers, and fruit, and predicted the intricate regulatory networks. A total of 9440 lncRNAs were obtained. LncRNA target prediction revealed 10,628 potential lncRNA-messenger RNA (mRNA) pairs, 9410 pairs functioning in a cis-acting fashion, and 1218 acting in a trans-acting fashion. Functional enrichment analysis showed that the targets were significantly enriched in molecular functions related to photosynthesis-antenna proteins, single-organism metabolic process and glutathione metabolism. Additionally, a total of 88 lncRNAs have various functions related to microRNAs (miRNAs) as miRNA precursors. Interactions between lncRNAs and miRNAs were predicted, 1341 possible interrelations between 187 mdm-miRNAs and 174 lncRNAs (1.84%) were identified. MSTRG.121644.5, MSTRG.121644.8, MSTRG.2929.2, MSTRG.3953.2, MSTRG.63448.2, MSTRG.9870.2, and MSTRG.9870.3 could participate in the functions in roots as competing endogenous RNAs (ceRNAs). MSTRG.11457.2, MSTRG.138614.2, and MSTRG.60895.2 could adopt special functions in the fruit by working with miRNAs. A further analysis showed that different tissues formed special lncRNA-miRNA-mRNA networks. MSTRG.60895.2-mdm-miR393-MD17G1009000 may participate in the anthocyanin metabolism in the fruit. These findings provide a comprehensive view of potential functions for lncRNAs, corresponding target genes, and related lncRNA-miRNA-mRNA networks, which will increase our knowledge of the underlying development mechanism in apple.


Asunto(s)
Malus , MicroARNs , ARN Largo no Codificante , Flores/genética , Flores/metabolismo , Frutas/genética , Frutas/metabolismo , Redes Reguladoras de Genes , Malus/genética , Malus/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Floema/genética , Floema/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , ARN Mensajero/genética
9.
Int J Mol Sci ; 20(23)2019 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-31795097

RESUMEN

Apple sugar and acid are the most important traits of apple fruit. Bud sport cultivars can provide abundant research materials for functional gene studies in apple. In this study, using bud sport materials with a rather different sugar and acid flavor, i.e., "Jonathan" and "Sweet Jonathan", we profiled the whole genome variations and transcriptional regulatory network during fruit developmental stages using whole genome sequencing and RNA-sequencing. Variation analysis identified 4,198,955 SNPs, 319,494 InDels, and 32,434 SVs between the two cultivars. In total, 4313 differentially expressed genes among all of the d 44,399 genes expressed were identified between the two cultivars during fruit development, and functional analysis revealed stress response and signal transduction related genes were enriched. Using 24,047 genes with a more variable expression value, we constructed 28 co-expression modules by weighted correlation network analysis. Deciphering of 14 co-expression modules associated with sugar or acid accumulation during fruit development revealed the hub genes associated with sugar and acid metabolism, e.g., MdDSP4, MdINVE, and MdSTP7. Furthermore, exploration of the intra network of the co-expression module indicated the close relationship between sugar and acid metabolism or sugar and stress. Motif-based sequence analysis of the 17 differentially expressed ATP-binding cassette transporter genes and Yeast one-hybrid assay identified and confirmed a transcription factor, MdBPC6, regulating the ATP-binding cassette (ABC) transporter genes and potentially participating in the apple fruit development or stress response. Collectively, all of the results demonstrated the use of parallel bud mutation sequencing and identified hub genes, and inferred regulatory relationships providing new information about apple fruit sugar and acid accumulation or stress response.


Asunto(s)
Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas , Malus/genética , Mutación , Estrés Fisiológico , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Ácidos/metabolismo , Frutas/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica , Redes Reguladoras de Genes , Genes de Plantas , Malus/crecimiento & desarrollo , Malus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Azúcares/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
10.
Biochem Biophys Res Commun ; 501(4): 885-892, 2018 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-29763606

RESUMEN

Hexokinase-2 (HK2), the initial as well as the rate-limiting step in glycolysis, is overexpressed in many human cancers, and correlates with poor clinical outcomes. Aerobic glycolysis is a hallmark of cancer, and drugs targeting its enzymes, including HK2, are being developed. However, the mechanisms of HK2 inhibition and the physiological significance of the HK2 inhibitors in cancer cells are rarely reported. Here, we show that microRNA-216a-5p (miR-216a-5p) inhibits HK2 expression by directly targeting its 3'-UTR in uveal melanoma cells. Through inhibition of HK2, miR-216a-5p dampens glycolysis by reducing HK activity, glucose uptake, lactate production, ATP generation, extracellular acidification rate (ECAR), and increasing oxygen consumption rate (OCR) in uveal melanoma cells. Importantly, glycolysis regulated by miR-216a-5p is critical for its regulating uveal melanoma tumor growth both in vitro and in vivo. miR-216a-5p expression is negatively correlated with HK2 expression and predicts better outcome in uveal melanoma patients. Our findings provide clues regarding the role of miR-216a-5p as a tumor suppressor in uveal melanoma through the inhibition of HK2. Targeting HK2 through miR-216a-5p could be a promising therapeutic strategy in uveal melanoma.


Asunto(s)
Glucólisis , Hexoquinasa/metabolismo , Melanoma/genética , Melanoma/patología , MicroARNs/metabolismo , Transducción de Señal , Neoplasias de la Úvea/genética , Neoplasias de la Úvea/patología , Aerobiosis , Animales , Secuencia de Bases , Línea Celular Tumoral , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Células HEK293 , Hexoquinasa/genética , Humanos , Melanoma/enzimología , Ratones , MicroARNs/genética , Pronóstico , Neoplasias de la Úvea/enzimología
11.
Opt Express ; 26(22): 28713-28726, 2018 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-30470044

RESUMEN

As optical networks undergo rapid development, the trade-offs among higher network service capability, and increasing operating expense (OPEX) about operations, administration and maintenance (OAM) become telecom operators' key obstacles. Intelligent and automatic OAM is considered to effectively satisfy service requirements, while dampening OPEX growth. In particular, machine learning (ML) has been investigated as a possible method of replacing human image recognition, nature language processing, automatic drive, and so forth. This is because of its essential feature extraction ability. ML application in optical networks was studied in a preliminary way recently. In ML-enabled optical networks, huge data storage and powerful computing resources are required to handle computer-intensive tasks performed in order to analyze features from big data sets. Integration of these two key resources into existing optical network architectures, in order to improve network performance, is an emerging challenge for ML-enabled optical networks. This article proposes a novel optical network architecture, which is based on software-defined networking (SDN), which is also named self-optimizing optical networks (SOON). First, we comb through intelligence development of optical networks, and introduce SOON as an OAM-oriented optical network architecture. Second, we demonstrate four typical applications within SOON, including tidal traffic prediction, alarm prediction, anomaly action detection, and routing and wavelength assignment. Finally, we discuss some open issues.

12.
Curr Opin Ophthalmol ; 27(2): 111-7, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26720777

RESUMEN

PURPOSE OF REVIEW: The aim of the present review was to summarize the new developments in anterior segment optical coherence tomography (AS-OCT) for glaucoma. RECENT FINDINGS: Recent years have demonstrated significant advances in the measurement of glaucoma through the use of AS-OCT. Furthermore, a more widespread use of AS-OCT in the clinical study of various glaucomas warrants review, which includes angel assessment, trabecular meshwork and Schlemm's canal assessment, and assessment of the filtering bleb and tube. SUMMARY: AS-OCT was recently developed and has become a crucial tool in glaucoma clinical practice. AS-OCT is a noncontact imaging device that provides the detailed structure of the anterior part of the eyes. In this review, the author will discuss the various clinical applications of AS-OCT for glaucoma disease, such as angle assessment, trabecular meshwork and Schlemm's canal assessment, or assessment of the filtering bleb and tube.


Asunto(s)
Glaucoma/diagnóstico , Tomografía de Coherencia Óptica , Humanos , Esclerótica , Malla Trabecular
13.
J Synchrotron Radiat ; 22(4): 1056-61, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26134811

RESUMEN

In recent years, increasing attention has been devoted to X-ray phase contrast imaging, since it can provide high-contrast images by using phase variations. Among the different existing techniques, Zernike phase contrast microscopy is one of the most popular phase-sensitive techniques for investigating the fine structure of the sample at high spatial resolution. In X-ray Zernike phase contrast microscopy, the image contrast is indeed a mixture of absorption and phase contrast. Therefore, this technique just provides qualitative information on the object, which makes the interpretation of the image difficult. In this contribution, an approach is proposed for quantitative phase retrieval in X-ray Zernike phase contrast microscopy. By shifting the phase of the direct light by π/2 and 3π/2, two images of the same object are measured successively. The phase information of the object can then be quantitatively retrieved by a proper combination of the measured images. Numerical experiments were carried out and the results confirmed the feasibility of the proposed method. It is expected that the proposed method will find widespread applications in biology, materials science and so on.

14.
J Synchrotron Radiat ; 22(4): 1091-5, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26134816

RESUMEN

For the first time, the three-dimensional (3D) ultrastructure of an intact rice pollen cell has been obtained using a full-field transmission hard X-ray microscope operated in Zernike phase contrast mode. After reconstruction and segmentation from a series of projection images, complete 3D structural information of a 35 µm rice pollen grain is presented at a resolution of ∼100 nm. The reconstruction allows a clear differentiation of various subcellular structures within the rice pollen grain, including aperture, lipid body, mitochondrion, nucleus and vacuole. Furthermore, quantitative information was obtained about the distribution of cytoplasmic organelles and the volume percentage of each kind of organelle. These results demonstrate that transmission X-ray microscopy can be quite powerful for non-destructive investigation of 3D structures of whole eukaryotic cells.


Asunto(s)
Imagenología Tridimensional , Microscopía/métodos , Oryza/ultraestructura , Polen/ultraestructura , Orgánulos/ultraestructura
15.
J Synchrotron Radiat ; 21(Pt 5): 1175-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25178009

RESUMEN

Poly(lactic co-glycolic acid) (PLGA) is widely used in diverse fields, especially in delivering biologically active proteins and drugs. For these applications, the knowledge of morphology and microstructure of PLGA micro-porous microspheres is of great importance since they strongly influence the drug delivering efficiency. In this study, micro-porous PLGA microspheres loaded by bovine serum albumin are investigated by using a full-field Zernike phase contrast transmission hard X-ray microscope. From three-dimensional reconstructions and segmentations, fundamental microstructural parameters such as size, shape, distribution and volume ratio among pores and proteins inside PLGA microspheres were obtained. These parameters are useful to understand the relationship between the internal microstructure and drug encapsulation, as well as the drug release efficiency of PLGA microspheres. The presented results demonstrate the capability of hard X-ray nano-tomography to characterize porous microspheres loaded with proteins and drugs, and also open a way to analyse, optimize and design new PLGA microspheres for specific applications.


Asunto(s)
Ácido Láctico/química , Microesferas , Polímeros/química , Tomografía por Rayos X/métodos , Sistemas de Liberación de Medicamentos , Imagenología Tridimensional , Tamaño de la Partícula , Poliésteres , Porosidad , Albúmina Sérica
16.
Opt Lett ; 39(4): 877-9, 2014 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-24562230

RESUMEN

In this Letter, we present a single-shot approach to quantitatively retrieve x-ray absorption and phase shift in grating interferometry. The proposed approach makes use of the energy-resolving capability of x-ray photon-counting detectors. The retrieval method is derived and presented and is tested based on numerical simulations, including photon shot noise. The good agreement between retrieval results and theoretical values confirms the feasibility of the presented approach.


Asunto(s)
Fotones , Conteo por Cintilación/métodos , Aluminio , Interferometría , Fenómenos Ópticos , Poliestirenos , Rayos X
17.
Heliyon ; 10(6): e27653, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38524558

RESUMEN

Objective: To explore the role and mechanisms of lncRNA nuclear enriched abundant transcript 1 (NEAT1) in angiogenesis of retinoblastoma (RB) cells. Methods: This study investigated the roles of NEAT1 in RB progression. The RNA expression levels of NEAT1, miR-106a, and hypoxia-inducible factor-1alpha (HIF-1α) examined by quantitative reverse transcription polymerase chain reaction (RT-qPCR) were compared between RB cells and normal retinal pigment epithelial (RPE) cells. The binding sites between NEAT1 and miR-106a, and between miR-106a and HIF-1α were predicted by the TargetScan database and verified using the dual-luciferase reporter assay. By transfection of overexpression plasmid or shRNA of NEAT1, and/or treatment of miR-106a inhibitor or mimics, proliferation, invasion, and angiogenesis of RB cells (measured by the MTT assay, the Transwell assay, and the tube formation assay, respectively) were compared between groups. Group comparisons were analyzed using one-way analysis of variance (ANOVA), and Tukey's post-hoc test was employed for further statistical assessment. P-value less than 0.05 was considered statistically significant. Results: The RNA expression levels of NEAT1 and HIF-1α were upregulated in RB cells, whereas the expression level of miR-106a was downregulated compared with RPE cells. NEAT1 overexpression or miR-106a knockdown advanced proliferation, invasion, and tube formation of RB cells. As a target of NEAT1, miR-106a could sponge HIF-1α to downregulate HIF-1α expression level. Functional analyses indicated that miR-106a knockdown reversed the inhibitory effects of NEAT1 silencing on the proliferation, invasion, and tube formation of RB cells. Furthermore, miR-106a overexpression suppressed RB cell angiogenesis by downregulating HIF-1α expression level. Conclusion: NEAT1 promoted proliferation, invasion, and angiogenesis of RB cells through upregulation of HIF-1α expression level by sponging miR-106a, demonstrating that NEAT1 may be a novel target for RB treatment.

18.
J Mol Histol ; 55(4): 581-588, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38758519

RESUMEN

Cadmium is a toxic heavy metal, which is both an environmental pollutant, and a threat to human health. A fluorescent probe was developed to detect Cd2+ selectively, sensitively, and quickly. This study reports the successful development of a polypeptide fluorescent probe TPE-HC (TPE-His-Pro-Gly-Cys) which selectively detects Cd2+ by Aggregation-Induced Emission effect. After fluorescence excitation, Cd2+ can be effectively detected based on the change of fluorescence intensity. The detection limit of Cd2+ in buffer solution was determined to be 151 nM (R2 = 0.9933). This probe exhibits high sensitivity, high cell permeabilit y, and low biological toxicity, and can perform live cell imaging under biological conditions. This study indicates that TPE-HC can detect Cd2+ in biological environments.


Asunto(s)
Cadmio , Colorantes Fluorescentes , Péptidos , Colorantes Fluorescentes/química , Cadmio/análisis , Humanos , Péptidos/química , Péptidos/análisis , Espectrometría de Fluorescencia/métodos , Límite de Detección , Células HeLa
19.
Neural Regen Res ; 19(11): 2522-2531, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-38526288

RESUMEN

JOURNAL/nrgr/04.03/01300535-202419110-00032/figure1/v/2024-03-08T184507Z/r/image-tiff High intraocular pressure causes retinal ganglion cell injury in primary and secondary glaucoma diseases, yet the molecular landscape characteristics of retinal cells under high intraocular pressure remain unknown. Rat models of acute hypertension ocular pressure were established by injection of cross-linked hyaluronic acid hydrogel (Healaflow®). Single-cell RNA sequencing was then used to describe the cellular composition and molecular profile of the retina following high intraocular pressure. Our results identified a total of 12 cell types, namely retinal pigment epithelial cells, rod-photoreceptor cells, bipolar cells, Müller cells, microglia, cone-photoreceptor cells, retinal ganglion cells, endothelial cells, retinal progenitor cells, oligodendrocytes, pericytes, and fibroblasts. The single-cell RNA sequencing analysis of the retina under acute high intraocular pressure revealed obvious changes in the proportions of various retinal cells, with ganglion cells decreased by 23%. Hematoxylin and eosin staining and TUNEL staining confirmed the damage to retinal ganglion cells under high intraocular pressure. We extracted data from retinal ganglion cells and analyzed the retinal ganglion cell cluster with the most distinct expression. We found upregulation of the B3gat2 gene, which is associated with neuronal migration and adhesion, and downregulation of the Tsc22d gene, which participates in inhibition of inflammation. This study is the first to reveal molecular changes and intercellular interactions in the retina under high intraocular pressure. These data contribute to understanding of the molecular mechanism of retinal injury induced by high intraocular pressure and will benefit the development of novel therapies.

20.
Curr Med Sci ; 44(2): 419-425, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38619684

RESUMEN

OBJECTIVE: Autosomal recessive bestrophinopathy (ARB), a retinal degenerative disease, is characterized by central visual loss, yellowish multifocal diffuse subretinal deposits, and a dramatic decrease in the light peak on electrooculogram. The potential pathogenic mechanism involves mutations in the BEST1 gene, which encodes Ca2+-activated Cl- channels in the retinal pigment epithelium (RPE), resulting in degeneration of RPE and photoreceptor. In this study, the complete clinical characteristics of two Chinese ARB families were summarized. METHODS: Pacific Biosciences (PacBio) single-molecule real-time (SMRT) sequencing was performed on the probands to screen for disease-causing gene mutations, and Sanger sequencing was applied to validate variants in the patients and their family members. RESULTS: Two novel mutations, c.202T>C (chr11:61722628, p.Y68H) and c.867+97G>A, in the BEST1 gene were identified in the two Chinese ARB families. The novel missense mutation BEST1 c.202T>C (p.Y68H) resulted in the substitution of tyrosine with histidine in the N-terminal region of transmembrane domain 2 of bestrophin-1. Another novel variant, BEST1 c.867+97G>A (chr11:61725867), located in intron 7, might be considered a regulatory variant that changes allele-specific binding affinity based on motifs of important transcriptional regulators. CONCLUSION: Our findings represent the first use of third-generation sequencing (TGS) to identify novel BEST1 mutations in patients with ARB, indicating that TGS can be a more accurate and efficient tool for identifying mutations in specific genes. The novel variants identified further broaden the mutation spectrum of BEST1 in the Chinese population.


Asunto(s)
Antagonistas de Receptores de Angiotensina , Enfermedades Hereditarias del Ojo , Enfermedades de la Retina , Humanos , Inhibidores de la Enzima Convertidora de Angiotensina , Bestrofinas/genética , Bestrofinas/metabolismo , Fenotipo
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