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1.
Nature ; 629(8011): 467-473, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38471529

RESUMEN

Prokaryotes have evolved intricate innate immune systems against phage infection1-7. Gabija is a highly widespread prokaryotic defence system that consists of two components, GajA and GajB8. GajA functions as a DNA endonuclease that is inactive in the presence of ATP9. Here, to explore how the Gabija system is activated for anti-phage defence, we report its cryo-electron microscopy structures in five states, including apo GajA, GajA in complex with DNA, GajA bound by ATP, apo GajA-GajB, and GajA-GajB in complex with ATP and Mg2+. GajA is a rhombus-shaped tetramer with its ATPase domain clustered at the centre and the topoisomerase-primase (Toprim) domain located peripherally. ATP binding at the ATPase domain stabilizes the insertion region within the ATPase domain, keeping the Toprim domain in a closed state. Upon ATP depletion by phages, the Toprim domain opens to bind and cleave the DNA substrate. GajB, which docks on GajA, is activated by the cleaved DNA, ultimately leading to prokaryotic cell death. Our study presents a mechanistic landscape of Gabija activation.


Asunto(s)
Bacillus cereus , Proteínas Bacterianas , Bacteriófagos , Microscopía por Crioelectrón , Inmunidad Innata , Adenosina Trifosfatasas/metabolismo , Adenosina Trifosfatasas/química , Adenosina Trifosfatasas/ultraestructura , Adenosina Trifosfato/química , Adenosina Trifosfato/metabolismo , Apoproteínas/química , Apoproteínas/inmunología , Apoproteínas/metabolismo , Apoproteínas/ultraestructura , Proteínas Bacterianas/química , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/ultraestructura , Bacteriófagos/inmunología , ADN/metabolismo , ADN/química , División del ADN , Magnesio/química , Magnesio/metabolismo , Modelos Moleculares , Unión Proteica , Dominios Proteicos , Viabilidad Microbiana , Bacillus cereus/química , Bacillus cereus/inmunología , Bacillus cereus/metabolismo , Bacillus cereus/ultraestructura , Estructura Cuaternaria de Proteína , ADN Primasa/química , ADN Primasa/metabolismo , ADN Primasa/ultraestructura , ADN-Topoisomerasas/química , ADN-Topoisomerasas/metabolismo , ADN-Topoisomerasas/ultraestructura
2.
Proc Natl Acad Sci U S A ; 120(13): e2217576120, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36943878

RESUMEN

Diabetes can result in impaired corneal wound healing. Mitochondrial dysfunction plays an important role in diabetic complications. However, the regulation of mitochondria function in the diabetic cornea and its impacts on wound healing remain elusive. The present study aimed to explore the molecular basis for the disturbed mitochondrial metabolism and subsequent wound healing impairment in the diabetic cornea. Seahorse analysis showed that mitochondrial oxidative phosphorylation is a major source of ATP production in human corneal epithelial cells. Live corneal biopsy punches from type 1 and type 2 diabetic mouse models showed impaired mitochondrial functions, correlating with impaired corneal wound healing, compared to nondiabetic controls. To approach the molecular basis for the impaired mitochondrial function, we found that Peroxisome Proliferator-Activated Receptor-α (PPARα) expression was downregulated in diabetic human corneas. Even without diabetes, global PPARα knockout mice and corneal epithelium-specific PPARα conditional knockout mice showed disturbed mitochondrial function and delayed wound healing in the cornea, similar to that in diabetic corneas. In contrast, fenofibrate, a PPARα agonist, ameliorated mitochondrial dysfunction and enhanced wound healing in the corneas of diabetic mice. Similarly, corneal epithelium-specific PPARα transgenic overexpression improved mitochondrial function and enhanced wound healing in the cornea. Furthermore, PPARα agonist ameliorated the mitochondrial dysfunction in primary human corneal epithelial cells exposed to diabetic stressors, which was impeded by siRNA knockdown of PPARα, suggesting a PPARα-dependent mechanism. These findings suggest that downregulation of PPARα plays an important role in the impaired mitochondrial function in the corneal epithelium and delayed corneal wound healing in diabetes.


Asunto(s)
Diabetes Mellitus Experimental , PPAR alfa , Ratones , Humanos , Animales , PPAR alfa/genética , PPAR alfa/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Córnea/metabolismo , Cicatrización de Heridas/fisiología , Ratones Noqueados , Mitocondrias/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(39): e2307722120, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37725654

RESUMEN

Single-cell RNA-seq (scRNA-seq) analysis of multiple samples separately can be costly and lead to batch effects. Exogenous barcodes or genome-wide RNA mutations can be used to demultiplex pooled scRNA-seq data, but they are experimentally or computationally challenging and limited in scope. Mitochondrial genomes are small but diverse, providing concise genotype information. We developed "mitoSplitter," an algorithm that demultiplexes samples using mitochondrial RNA (mtRNA) variants, and demonstrated that mtRNA variants can be used to demultiplex large-scale scRNA-seq data. Using affordable computational resources, mitoSplitter can accurately analyze 10 samples and 60,000 cells in 6 h. To avoid the batch effects from separated experiments, we applied mitoSplitter to analyze the responses of five non-small cell lung cancer cell lines to BET (Bromodomain and extraterminal) chemical degradation in a multiplexed fashion. We found the synthetic lethality of TOP2A inhibition and BET chemical degradation in BET inhibitor-resistant cells. The result indicates that mitoSplitter can accelerate the application of scRNA-seq assays in biomedical research.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , ARN Mitocondrial , Análisis de Expresión Génica de una Sola Célula , Mitocondrias/genética
4.
Proc Natl Acad Sci U S A ; 119(33): e2207489119, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35939707

RESUMEN

The mechanistic target of rapamycin (mTOR) is assembled into signaling complexes of mTORC1 or mTORC2, and plays key roles in cell metabolism, stress response, and nutrient and growth factor sensing. Accumulating evidence from human and animal model studies has demonstrated a pathogenic role of hyperactive mTORC1 in age-related macular degeneration (AMD). The retinal pigment epithelium (RPE) is a primary injury site in AMD. In mouse models of RPE-specific deletion of Tuberous sclerosis 1 (Tsc1), which encodes an upstream suppressor of mTORC1, the hyperactivated mTORC1 metabolically reprogrammed the RPE and led to the degeneration of the outer retina and choroid (CH). In the current study, we use single-cell RNA sequencing (scRNA-seq) to identify an RPE mTORC1 downstream protein, dopamine- and cyclic AMP-regulated phosphoprotein of molecular weight 32,000 (DARPP-32). DARPP-32 was not found in healthy RPE but localized to drusen and basal linear deposits in human AMD eyes. In animal models, overexpressing DARPP-32 by adeno-associated virus (AAV) led to abnormal RPE structure and function. The data indicate that DARPP-32 is a previously unidentified signaling protein subjected to mTORC1 regulation and may contribute to RPE degeneration in AMD.


Asunto(s)
Fosfoproteína 32 Regulada por Dopamina y AMPc , Degeneración Macular , Diana Mecanicista del Complejo 1 de la Rapamicina , Epitelio Pigmentado de la Retina , Animales , Modelos Animales de Enfermedad , Fosfoproteína 32 Regulada por Dopamina y AMPc/metabolismo , Activación Enzimática , Humanos , Degeneración Macular/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Ratones , Retina/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Transducción de Señal
5.
BMC Genomics ; 25(1): 815, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39210263

RESUMEN

BACKGROUND: The DELLA proteins, a class of GA signaling repressors, belong to the GRAS family of plant-specific nuclear proteins. Members of DELLA gene family encode transcriptional regulators with diverse functions in plant development and abiotic stress responses. To date, DELLAs have been identified in various plant species, such as Arabidopsis thaliana, Malus domestica, Populus trichocarpa, and other land plants. Most information of DELLA family genes was obtained from A. thaliana, whereas little is known about the DELLA gene family in blueberry. RESULTS: In this study, we identified three DELLA genes in blueberry (Vaccinium darrowii, VdDELLA) and provided a complete overview of VdDELLA gene family, describing chromosome localization, protein properties, conserved domain, motif organization, and phylogenetic analysis. Three VdDELLA members, containing two highly conserved DELLA domain and GRAS domain, were distributed across three chromosomes. Additionally, cis-acting elements analysis indicated that VdDELLA genes might play a critical role in blueberry developmental processes, hormone, and stress responses. Expression analysis using quantitative real-time PCR (qRT-PCR) revealed that all of three VdDELLA genes were differentially expressed across various tissues. VdDELLA2 was the most highly expressed VdDELLA in all denoted tissues, with a highest expression in mature fruits. In addition, all of the three VdDELLA genes actively responded to diverse abiotic stresses. Based on qRT-PCR analysis, VdDELLA2 might act as a key regulator in V. darrowii in response to salt stress, whereas VdDELLA1 and VdDELLA2 might play an essential role in cold stress response. Under drought stress, all of three VdDELLA genes were involved in mediating drought response. Furthermore, their transiently co-localization with nuclear markers in A. thaliana protoplasts demonstrated their transcriptional regulator roles. CONCLUSIONS: In this study, three VdDELLA genes were identified in V. darrowii genome. Three VdDELLA genes were closely related to the C. moschata DELLA genes, S. lycopersicum DELLA genes, and M. domestica DELLA genes, respectively, indicating their similar biological functions. Expression analysis indicated that VdDELLA genes were highly efficient in blueberry fruit development. Expression patterns under different stress conditions revealed the differentially expressed VdDELLA genes responding to salt, drought, and cold stress. Overall, these results enrich our understanding of evolutionary relationship and potential functions of VdDELLA genes, which provide valuable information for further studies on genetic improvement of the plant yield and plant resistance.


Asunto(s)
Arándanos Azules (Planta) , Regulación de la Expresión Génica de las Plantas , Familia de Multigenes , Filogenia , Proteínas de Plantas , Estrés Fisiológico , Arándanos Azules (Planta)/genética , Estrés Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Perfilación de la Expresión Génica , Cromosomas de las Plantas/genética
6.
BMC Genomics ; 25(1): 434, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38693497

RESUMEN

BACKGROUND: WOX genes are a class of plant-specific transcription factors. The WUSCHEL-related homeobox (WOX) family is a member of the homeobox transcription factor superfamily. Previous studies have shown that WOX members play important roles in plant growth and development. However, studies of the WOX gene family in blueberry plants have not been reported. RESULTS: In order to understand the biological function of the WOX gene family in blueberries, bioinformatics were used methods to identify WOX gene family members in the blueberry genome, and analyzed the basic physical and chemical properties, gene structure, gene motifs, promoter cis-acting elements, chromosome location, evolutionary relationships, expression pattern of these family members and predicted their functions. Finally, 12 genes containing the WOX domain were identified and found to be distributed on eight chromosomes. Phylogenetic tree analysis showed that the blueberry WOX gene family had three major branches: ancient branch, middle branch, and WUS branch. Blueberry WOX gene family protein sequences differ in amino acid number, molecular weight, isoelectric point and hydrophobicity. Predictive analysis of promoter cis-acting elements showed that the promoters of the VdWOX genes contained abundant light response, hormone, and stress response elements. The VdWOX genes were induced to express in both stems and leaves in response to salt and drought stress. CONCLUSIONS: Our results provided comprehensive characteristics of the WOX gene family and important clues for further exploration of its role in the growth, development and resistance to various stress in blueberry plants.


Asunto(s)
Arándanos Azules (Planta) , Filogenia , Regiones Promotoras Genéticas , Arándanos Azules (Planta)/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Familia de Multigenes , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Estrés Fisiológico/genética , Cromosomas de las Plantas/genética , Evolución Molecular , Biología Computacional/métodos
7.
Brief Bioinform ; 23(2)2022 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-35279714

RESUMEN

Messenger RNA (mRNA) vaccines have shown great potential for anti-tumor therapy due to the advantages in safety, efficacy and industrial production. However, it remains a challenge to identify suitable cancer neoantigens that can be targeted for mRNA vaccines. Abnormal alternative splicing occurs in a variety of tumors, which may result in the translation of abnormal transcripts into tumor-specific proteins. High-throughput technologies make it possible for systematic characterization of alternative splicing as a source of suitable target neoantigens for mRNA vaccine development. Here, we summarized difficulties and challenges for identifying alternative splicing-derived cancer neoantigens from RNA-seq data and proposed a conceptual framework for designing personalized mRNA vaccines based on alternative splicing-derived cancer neoantigens. In addition, several points were presented to spark further discussion toward improving the identification of alternative splicing-derived cancer neoantigens.


Asunto(s)
Empalme Alternativo , Neoplasias , Antígenos de Neoplasias/genética , Humanos , Inmunoterapia , Neoplasias/genética , Neoplasias/terapia , ARN Mensajero/genética , Vacunas Sintéticas , Vacunas de ARNm
8.
Bioinformatics ; 39(10)2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37740953

RESUMEN

MOTIVATION: Cell-cell interactions (CCIs) play critical roles in many biological processes such as cellular differentiation, tissue homeostasis, and immune response. With the rapid development of high throughput single-cell RNA sequencing (scRNA-seq) technologies, it is of high importance to identify CCIs from the ever-increasing scRNA-seq data. However, limited by the algorithmic constraints, current computational methods based on statistical strategies ignore some key latent information contained in scRNA-seq data with high sparsity and heterogeneity. RESULTS: Here, we developed a deep learning framework named DeepCCI to identify meaningful CCIs from scRNA-seq data. Applications of DeepCCI to a wide range of publicly available datasets from diverse technologies and platforms demonstrate its ability to predict significant CCIs accurately and effectively. Powered by the flexible and easy-to-use software, DeepCCI can provide the one-stop solution to discover meaningful intercellular interactions and build CCI networks from scRNA-seq data. AVAILABILITY AND IMPLEMENTATION: The source code of DeepCCI is available online at https://github.com/JiangBioLab/DeepCCI.


Asunto(s)
Aprendizaje Profundo , Perfilación de la Expresión Génica , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Programas Informáticos , Análisis por Conglomerados
9.
Mol Phylogenet Evol ; : 108182, 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39222738

RESUMEN

The increasing use of genome-scale data has significantly facilitated phylogenetic analyses, contributing to the dissection of the underlying evolutionary mechanisms that shape phylogenetic incongruences, such as incomplete lineage sorting (ILS) and hybridization. Lilieae, a prominent member of the Liliaceae family, comprises four genera and approximately 260 species, representing 43 % of all species within Liliaceae. They possess high ornamental, medicinal and edible value. Yet, no study has explored the validity of various genome-scale data in phylogenetic analyses within this tribe, nor have potential evolutionary mechanisms underlying its phylogenetic incongruences been investigated. Here, transcriptome, Angiosperms353, plastid and mitochondrial data, were collected from 50 to 93 samples of Lilieae, covering all four recognized genera. Multiple datasets were created and used for phylogenetic analyses based on concatenated and coalescent-based methods. Evolutionary rates of different datasets were calculated, and divergence times were estimated. Various approaches, including coalescence simulation, Quartet Sampling (QS), calculation of concordance factors (gCF and sCF), as well as MSCquartets and reticulate network inference, were carried out to infer the phylogenetic discordances and analyze their underlying mechanisms using a reduced 33-taxon dataset. Despite extensive phylogenetic discordances among gene trees, robust phylogenies were inferred from nuclear and plastid data compared to mitochondrial data, with lower synonymous substitution detected in mitochondrial genes than in nuclear and plastid genes. Significant ILS was detected across the phylogeny of Lilieae, with clear evidence of reticulate evolution identified. Divergence time estimation indicated that most of lineages in Lilieae diverged during a narrow time frame (ranging from 5.0 Ma to 10.0 Ma), consistent with the notion of rapid radiation evolution. Our results suggest that integrating transcriptomic and plastid data can serve as cost-effective and efficient tools for phylogenetic inference and evolutionary analysis within Lilieae, and Angiosperms353 data is also a favorable choice. Mitochondrial data are more suitable for phylogenetic analyses at higher taxonomic levels due to their stronger conservation and lower synonymous substitution rates. Significant phylogenetic incongruences detected in Lilieae were caused by both incomplete lineage sorting (ILS) and reticulate evolution, with hybridization and "ghost introgression" likely prevalent in the evolution of Lilieae species. Our findings provide new insights into the phylogeny of Lilieae, enhancing our understanding of the evolution of species in this tribe.

10.
Opt Lett ; 49(7): 1774-1777, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38560860

RESUMEN

An ultra-broadband TM-pass polarizer is designed, fabricated, and experimentally demonstrated based on subwavelength grating (SWG) metamaterials in a lithium niobate on an insulator (LNOI) platform. According to our simulation, the designed device is predicted to work at a 220 nm wavelength range from 1460 to 1680 nm, covering the S-, C-, L-, U-bands of optical fiber communication. By depositing and subsequently etching a silicon nitride thin film atop the LNOI chip, the SWG structures are formed successfully by using complementary metal-oxide semiconductor (CMOS)-compatible fabrication processes. The measured results show a high polarization extinction ratio larger than 20 dB and a relatively low insertion loss below 2.5 dB over a 130 nm wavelength range from 1500 to 1630 nm, mainly limited by the operation bandwidth of our laser source.

11.
Oncology ; 102(2): 168-182, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37699361

RESUMEN

INTRODUCTION: SMG5 is involved in tumor cell development and viewed as a potential target for immunotherapy. The purpose of this study was to systematically analyze the expression level, function, and prognostic value of SMG5 in pan-cancers. METHODS: Differential expression of SMG5 in normal and tumor tissues was analyzed using The Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression Database (GTEx) data. Survival analysis was performed by Kaplan-Meier method and Cox risk regression. The relationship between SMG5 expression and lymphocyte abundance, tumor cell immune infiltration level, molecular and immune subtypes as well as immune checkpoints was analyzed by tumor-immune system interactions database (TISIDB), Tumor Immune Estimation Resource (TIMER), and Sangerbox databases. The correlation between SMG5 and immune scores was studied using the Estimation of Stromal and Immune Cells in Malignant Tumours using Expression (ESTIMATE) data algorithm. Further, drug sensitivity analysis of SMG5 with low-grade glioma (LGG) was conducted using the CellMiner database. RESULTS: SMG5 was highly expressed in 23 tumors and only had a significant impact on the prognosis of patients with LGG only. In addition, in tumor microenvironment and tumor immune analysis, we found that the level of immune infiltration, tumor mutational load, microsatellite instability, and immune checkpoints of LGG were significantly correlated with SMG5 expression. Furthermore, SMG5 was significantly associated with immune scores, stromal scores, and sensitivity of some drugs in LGG. CONCLUSION: SMG5 is differentially expressed in several cancers and is significantly associated with prognosis, immune microenvironment, and immune checkpoints in LGG patients. Therefore, SMG5 could be a potential pan-cancer biomarker and an immunotherapeutic target for LGG.


Asunto(s)
Glioma , Humanos , Pronóstico , Biomarcadores de Tumor/genética , Algoritmos , Diferenciación Celular , Microambiente Tumoral , Proteínas Portadoras
12.
Arch Biochem Biophys ; 754: 109962, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38499055

RESUMEN

Acetohydroxyacid synthase (AHAS) is one of the key enzymes of the biosynthesis of branched-chain amino acids, it is also an effective target for the screening of herbicides and antibiotics. In this study we present a method for preparing Escherichia coli AHAS I holoenzyme (EcAHAS I) with exceptional stability, which provides a solid ground for us to re-investigate the in vitro catalytic properties of the protein. The results show EcAHAS I synthesized in this way exhibits similar function to Bacillus subtilis acetolactate synthase in its catalysis with pyruvate and 2-ketobutyrate (2-KB) as dual-substrate, producing four 2-hydroxy-3-ketoacids including (S)-2-acetolactate, (S)-2-aceto-2-hydroxybutyrate, (S)-2-propionyllactate, and (S)-2-propionyl-2-hydroxybutyrate. Quantification of the reaction indicates that the two substrates almost totally consume, and compound (S)-2-aceto-2- hydroxybutyrate forms in the highest yield among the four major products. Moreover, the protein also condenses two molecules of 2-KB to furnish (S)-2-propionyl-2-hydroxybutyrate. Further exploration manifests that EcAHAS I ligates pyruvate/2-KB and nitrosobenzene to generate two arylhydroxamic acids N-hydroxy-N-phenylacetamide and N-hydroxy-N-phenyl- propionamide. These findings enhance our comprehension of the catalytic characteristics of EcAHAS I. Furthermore, the application of this enzyme as a catalyst in construction of C-N bonds displays promising potential.


Asunto(s)
Acetolactato Sintasa , Escherichia coli , Acetolactato Sintasa/química , Glucógeno Sintasa , Hidroxibutiratos , Piruvatos , Holoenzimas
13.
BMC Cancer ; 24(1): 805, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38969990

RESUMEN

BACKGROUND: Differentiation of glioma and solitary brain metastasis (SBM), which requires biopsy or multi-disciplinary diagnosis, remains sophisticated clinically. Histogram analysis of MR diffusion or molecular imaging hasn't been fully investigated for the differentiation and may have the potential to improve it. METHODS: A total of 65 patients with newly diagnosed glioma or metastases were enrolled. All patients underwent DWI, IVIM, and APTW, as well as the T1W, T2W, T2FLAIR, and contrast-enhanced T1W imaging. The histogram features of apparent diffusion coefficient (ADC) from DWI, slow diffusion coefficient (Dslow), perfusion fraction (frac), fast diffusion coefficient (Dfast) from IVIM, and MTRasym@3.5ppm from APTWI were extracted from the tumor parenchyma and compared between glioma and SBM. Parameters with significant differences were analyzed with the logistics regression and receiver operator curves to explore the optimal model and compare the differentiation performance. RESULTS: Higher ADCkurtosis (P = 0.022), frackurtosis (P<0.001),and fracskewness (P<0.001) were found for glioma, while higher (MTRasym@3.5ppm)10 (P = 0.045), frac10 (P<0.001),frac90 (P = 0.001), fracmean (P<0.001), and fracentropy (P<0.001) were observed for SBM. frackurtosis (OR = 0.431, 95%CI 0.256-0.723, P = 0.002) was independent factor for SBM differentiation. The model combining (MTRasym@3.5ppm)10, frac10, and frackurtosis showed an AUC of 0.857 (sensitivity: 0.857, specificity: 0.750), while the model combined with frac10 and frackurtosis had an AUC of 0.824 (sensitivity: 0.952, specificity: 0.591). There was no statistically significant difference between AUCs from the two models. (Z = -1.14, P = 0.25). CONCLUSIONS: The frac10 and frackurtosis in enhanced tumor region could be used to differentiate glioma and SBM and (MTRasym@3.5ppm)10 helps improving the differentiation specificity.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/patología , Glioma/diagnóstico por imagen , Glioma/patología , Femenino , Masculino , Persona de Mediana Edad , Adulto , Diagnóstico Diferencial , Anciano , Imagen de Difusión por Resonancia Magnética/métodos , Curva ROC , Imagen por Resonancia Magnética/métodos
14.
J Cardiovasc Pharmacol ; 83(5): 474-481, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38113918

RESUMEN

ABSTRACT: Studies have examined the therapeutic effect of levosimendan on cardiovascular diseases such as heart failure, perioperative cardiac surgery, and septic shock, but the specific mechanism in mice remains largely unknown. This study aimed to investigate the relaxation mechanism of levosimendan in the thoracic aorta smooth muscle of mice. Levosimendan-induced relaxation of isolated thoracic aortic rings that were precontracted with norepinephrine or KCl was recorded in an endothelium-independent manner. Vasodilatation by levosimendan was not associated with the production of the endothelial relaxation factors nitric oxide and prostaglandins. The voltage-dependent K + channel (K V ) blocker (4-aminopyridine) and selective K Ca blocker (tetraethylammonium) had no effect on thoracic aortas treated with levosimendan, indicating that K V and K Ca channels may not be involved in the levosimendan-induced relaxation mechanism. Although the inwardly rectifying K + channel (K ir ) blocker (barium chloride) and the K ATP channel blocker (glibenclamide) significantly inhibited levosimendan-induced vasodilation in the isolated thoracic aorta, barium chloride had a much stronger inhibitory effect on levosimendan-induced vasodilation than glibenclamide, suggesting that levosimendan-induced vasodilation may be mediated by K ir channels. The vasodilation effect and expression of K ir 2.1 induced by levosimendan were further enhanced by the PKC inhibitor staurosporine. Extracellular calcium influx was inhibited by levosimendan without affecting intracellular Ca 2+ levels in the isolated thoracic aorta. These results suggest that K ir channels play a more important role than K ATP channels in regulating vascular tone in larger arteries and that the activity of the K ir channel is enhanced by the PKC pathway.


Asunto(s)
Aorta Torácica , Músculo Liso Vascular , Proteína Quinasa C , Simendán , Vasodilatación , Animales , Aorta Torácica/efectos de los fármacos , Aorta Torácica/metabolismo , Simendán/farmacología , Masculino , Vasodilatación/efectos de los fármacos , Proteína Quinasa C/metabolismo , Proteína Quinasa C/antagonistas & inhibidores , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Ratones , Canales de Potasio de Rectificación Interna/metabolismo , Canales de Potasio de Rectificación Interna/antagonistas & inhibidores , Canales de Potasio de Rectificación Interna/efectos de los fármacos , Vasodilatadores/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Bloqueadores de los Canales de Potasio/farmacología
15.
Fish Shellfish Immunol ; 148: 109466, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38432538

RESUMEN

To evade host antiviral response, viruses have evolved to take advantage of their noncoding RNAs (ncRNAs). Snakehead vesiculovirus (SHVV), a newly isolated fish rhabdovirus from diseased hybrid snakehead, has caused high mortality to the cultured snakehead fish during the past years in China. However, little is known about the mechanisms of its pathogenicity. Our study revealed that overexpression of the 30-nt leader RNA promoted SHVV replication. RNA-protein binding investigation revealed that SHVV leader RNA could interact with host 40S ribosomal protein S8 (RPS8) and 60S ribosomal protein L13a (L13a). Furthermore, we found that SHVV infection upregulated RPS8 and L13a, and in turn, overexpression of RPS8 or L13a inhibited, while knockdown of RPS8 or L13a promoted, SHVV replication, suggesting that RPS8 and L13a acted as host antiviral factors in response to SHVV infection. In addition, our study revealed that RPS8- or L13a-mediated inhibition of SHVV replication could be restored by co-transfection with leader RNA, suggesting that the interaction between leader RNA and RPS8 or L13a might affect the anti-SHVV effects of RPS8 and L13a. Taken together, these results suggest that SHVV leader RNA can interact with the host antiviral factors RPS8 and L13a, and promote SHVV replication. This study provides a better understanding of the molecular mechanism of the pathogenesis of SHVV and a potential antiviral strategy against SHVV infection.


Asunto(s)
Perciformes , Animales , Perciformes/fisiología , Vesiculovirus/genética , ARN Viral/genética , Replicación Viral , Antivirales/farmacología
16.
BMC Neurol ; 24(1): 45, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273251

RESUMEN

PURPOSE: To explore the predictive value of radiomics in predicting stroke-associated pneumonia (SAP) in acute ischemic stroke (AIS) patients and construct a prediction model based on clinical features and DWI-MRI radiomics features. METHODS: Univariate and multivariate logistic regression analyses were used to identify the independent clinical predictors for SAP. Pearson correlation analysis and the least absolute shrinkage and selection operator with ten-fold cross-validation were used to calculate the radiomics score for each feature and identify the predictive radiomics features for SAP. Multivariate logistic regression was used to combine the predictive radiomics features with the independent clinical predictors. The prediction performance of the SAP models was evaluated using receiver operating characteristics (ROC), calibration curves, decision curve analysis, and subgroup analyses. RESULTS: Triglycerides, the neutrophil-to-lymphocyte ratio, dysphagia, the National Institutes of Health Stroke Scale (NIHSS) score, and internal carotid artery stenosis were identified as clinically independent risk factors for SAP. The radiomics scores in patients with SAP were generally higher than in patients without SAP (P < 0. 05). There was a linear positive correlation between radiomics scores and NIHSS scores, as well as between radiomics scores and infarct volume. Infarct volume showed moderate performance in predicting the occurrence of SAP, with an AUC of 0.635. When compared with the other models, the combined prediction model achieved the best area under the ROC (AUC) in both training (AUC = 0.859, 95% CI 0.759-0.936) and validation (AUC = 0.830, 95% CI 0.758-0.896) cohorts (P < 0.05). The calibration curves and decision curve analysis further confirmed the clinical value of the nomogram. Subgroup analysis showed that this nomogram had potential generalization ability. CONCLUSION: The addition of the radiomics features to the clinical model improved the prediction of SAP in AIS patients, which verified its feasibility.


Asunto(s)
Accidente Cerebrovascular Isquémico , Neumonía , Accidente Cerebrovascular , Estados Unidos , Humanos , Estudios de Factibilidad , Radiómica , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/epidemiología , Infarto
17.
Org Biomol Chem ; 22(30): 6135-6140, 2024 07 31.
Artículo en Inglés | MEDLINE | ID: mdl-39011846

RESUMEN

A new chemodosimeter SWJT-31 with an aggregation-induced emission (AIE) effect was designed and constructed. Upon increasing the water fraction in the solution, it exhibited typical AIE, which showed bright red fluorescence at 610 nm. SWJT-31 could sensitively and specifically recognize hydrazine by the TICT effect with an LOD of 33.8 nM, which was much lower than the standard of the USEPA. A portable test strip prepared using SWJT-31 was also developed for the visual detection of hydrazine. Eventually, it was successfully used for the detection of hydrazine in water samples and HeLa cells.


Asunto(s)
Colorantes Fluorescentes , Hidrazinas , Imidazoles , Hidrazinas/química , Humanos , Células HeLa , Imidazoles/química , Imidazoles/síntesis química , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Imagen Óptica , Estructura Molecular
18.
Nanotechnology ; 35(20)2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38316042

RESUMEN

A novel defect control approach based on laminated HfO2/ZrO2with multifunctional TiN/Mo/TiOxNyelectrode is proposed to significantly improve the endurance and data retention in HZO-based ferroelectric capacitor. The O-rich interface reduces leakage current and prolong the endurance up to 1011cycles while retaining a 2Pr value of 34 (µC cm-2) at 3.4 MV cm-1. Using first-principles calculations and experiments, we demonstrate that the enhancement of endurance is ascribed to the higher migration barrier of oxygen vacancies within the laminated HZO film and higher work function of MoOx/TiOxNybetween top electrode and the insulating oxide. This 2.5 nm thick TiOxNybarrier further increase the grain size of HZO, lowering the activation field and thus improving polarization reversal speed. This interfacial layer further decreases the overall capacitance, increases the depolarization field, thereby enhancing the data retention. By fitting the data using the Arrhenius equation, we demonstrate a 10 years data retention is achieved at 109.6 °C, surpassing traditional SS-HZO of 78.2 °C with a 450 °C rapid thermal annealing (required by backend-of-the-line). This work elucidates that interfacial engineering serves as a crucial technology capable of resolving the endurance, storage capability, and high-temperature data retention issues for ferroelectric memory.

19.
Clin Chem Lab Med ; 62(1): 97-110, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-37435827

RESUMEN

OBJECTIVES: To update traditional "wet" matrices to dried blood spot (DBS) sampling, based on the liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) technique, and develop a method for simultaneous analyzing caffeine and its three primary metabolites (theobromine, paraxanthine, and theophylline), supporting routine therapeutic drug monitoring (TDM) for preterm infants. METHODS: DBS samples were prepared by a two-step quantitative sampling method, i.e., volumetric sampling of a quantitative 10 µL volume of peripheral blood and an 8 mm diameter whole punch extraction by a methanol/water (80/20, v/v) mixture containing 125 mM formic acid. Four paired stable isotope labeled internal standards and a collision energy defect strategy were applied for the method optimization. The method was fully validated following international guidelines and industrial recommendations on DBS analysis. Cross validation with previously developed plasma method was also proceeded. The validated method was then implemented on the TDM for preterm infants. RESULTS: The two-step quantitative sampling strategy and a high recovery extraction method were developed and optimized. The method validation results were all within the acceptable criteria. Satisfactory parallelism, concordance, and correlation were observed between DBS and plasma concentrations of the four analytes. The method was applied to provide routine TDM services to 20 preterm infants. CONCLUSIONS: A versatile LC-MS/MS platform for simultaneous monitoring caffeine and its three primary metabolites was developed, fully validated, and successfully applied into the routine clinical TDM practices. Sampling method switching from "wet" matrices to "dry" DBS will facilitate and support the precision dosing of caffeine for preterm infants.


Asunto(s)
Cafeína , Recien Nacido Prematuro , Humanos , Recién Nacido , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Plasma , Pruebas con Sangre Seca/métodos , Monitoreo de Drogas/métodos , Reproducibilidad de los Resultados
20.
J Biochem Mol Toxicol ; 38(6): e23746, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38769694

RESUMEN

To identify the role of enterotoxin-related genes in colorectal cancer (CRC) development and progression. Upregulated differentially expressed genes shared by three out of five Gene Expression Omnibus (GEO) data sets were included to screen the key enterotoxin-induced oncogenes (EIOGs) according to criteria oncogene definition, enrichment, and protein-protein interaction (PPI) network analysis, followed by prognosis survival, immune infiltration, and protential drugs analyses was performed via integration of RNA-sequencing data and The Cancer Genome Atlas-derived clinical profiles. We screened nine common key EIOGs from at least three GEO data sets. A Cox proportional hazards regression models verified that more alive cases, decreased overall survival, and highest 4-year survival prediction in CRC patients with high-risk score. Protein tyrosine phosphatase receptor type F polypeptide-interacting protein alpha-4 (PPFIA4), STY11, SCN3B, and SPTBN5 were shared in the same PPI network. Immune infiltration results showed that SCN3B and synaptotagmin 11 expression were obviously associated with B cell, macrophage, myeloid dendritic cell, neutrophils, and T cell CD4+ and CD8+ in both colon adenocarcinoma and rectal adenocarcinoma. CHIR-99021, MLN4924, and YK4-279 were identified as the potential drugs for treatment. Finally, upregulated EIOGs genes PPFIA4 and SCN3B were found in colon adenocarcinoma and PPFIA4 and SCN3B were proved to promote cell proliferation and migration in vitro. We demonstrated here that EIOGs promoting a malignancy phenotype was related with poor survival and prognosis in CRC, which might be served as novel therapeutic targets in CRC management.


Asunto(s)
Neoplasias Colorrectales , Enterotoxinas , Humanos , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Mapas de Interacción de Proteínas
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