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1.
Proc Natl Acad Sci U S A ; 120(18): e2218856120, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37094162

RESUMEN

The anomalous metallic state (AMS) emerging from a quantum superconductor-to-metal transition is a subject of great current interest since this exotic quantum state exhibits unconventional transport properties that challenge the core physics principles of Fermi liquid theory. As the AMS concept is historically derived from disordered two-dimensional (2D) systems, related studies have predominately concentrated on 2D materials. The AMS behaviors in three-dimensional (3D) systems have been rarely reported to date, which raises intriguing questions on the fundamental nature of pertinent physics. Here, we report experimental evidence for a 3D AMS in highly compressed titanium metal that exhibits superconductivity with a critical temperature (Tc) reaching near-record 25.1 K among elemental superconductors, offering a favorable material template for exploring 3D AMS. At sufficiently strong magnetic fields, unusual transport behaviors set in over a wide pressure range, showcasing AMS hallmarks of a low-temperature saturation resistance below the Drude value and giant positive magnetoresistance. These findings reveal a 3D AMS in simple elemental systems and, more importantly, provide a fresh platform for probing the decades-long enigmatic underlying physics.

2.
Circ Res ; 132(5): 586-600, 2023 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-36756875

RESUMEN

BACKGROUND: Myocardial infarction (MI) elicits cardiac fibroblast activation and extracellular matrix (ECM) deposition to maintain the structural integrity of the heart. Recent studies demonstrate that Fap (fibroblast activation protein)-a prolyl-specific serine protease-is an important marker of activated cardiac fibroblasts after MI. METHODS: Left ventricle and plasma samples from patients and healthy donors were used to analyze the expression level of FAP and its prognostic value. Echocardiography and histological analysis of heart sections were used to analyze cardiac functions, scar formation, ECM deposition and angiogenesis after MI. RNA-Sequencing, biochemical analysis, cardiac fibroblasts (CFs) and endothelial cells co-culture were used to reveal the molecular and cellular mechanisms by which Fap regulates angiogenesis. RESULTS: We found that Fap is upregulated in patient cardiac fibroblasts after cardiac injuries, while plasma Fap is downregulated and functions as a prognostic marker for cardiac repair. Genetic or pharmacological inhibition of Fap in mice significantly improved cardiac function after MI. Histological and transcriptomic analyses showed that Fap inhibition leads to increased angiogenesis in the peri-infarct zone, which promotes ECM deposition and alignment by cardiac fibroblasts and prevents their overactivation, thereby limiting scar expansion. Mechanistically, we found that BNP (brain natriuretic peptide) is a novel substrate of Fap that mediates postischemic angiogenesis. Fap degrades BNP to inhibit vascular endothelial cell migration and tube formation. Pharmacological inhibition of Fap in Nppb (encoding pre-proBNP) or Npr1 (encoding the BNP receptor)-deficient mice showed no cardioprotective effects, suggesting that BNP is a physiological substrate of Fap. CONCLUSIONS: This study identifies Fap as a negative regulator of cardiac repair and a potential drug target to treat MI. Inhibition of Fap stabilizes BNP to promote angiogenesis and cardiac repair.


Asunto(s)
Infarto del Miocardio , Péptido Natriurético Encefálico , Animales , Ratones , Cicatriz , Endopeptidasas/genética , Células Endoteliales/patología , Infarto del Miocardio/patología , Péptido Natriurético Encefálico/genética
3.
BMC Biol ; 22(1): 240, 2024 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-39443951

RESUMEN

BACKGROUND: The rumen microbiome plays an essential role in maintaining ruminants' growth and performance even under extreme environmental conditions, however, which factors influence rumen microbiome stability when ruminants are reared in such habitats throughout the year is unclear. Hence, the rumen microbiome of yak (less domesticated) and cattle (domesticated) reared on the Qinghai-Tibetan Plateau through the year were assessed to evaluate temporal changes in their composition, function, and stability. RESULTS: Rumen fermentation characteristics and pH significantly shifted across seasons in both cattle and yak, but the patterns differed between the two ruminant species. Ruminal enzyme activity varied with season, and production of xylanase and cellulase was greater in yak compared to cattle in both fall and winter. The rumen bacterial community varied with season in both yak and cattle, with higher alpha diversity and similarity (beta diversity) in yak than cattle. The diversity indices of eukaryotic community did not change with season in both ruminant species, but higher similarity was observed in yak. In addition, the similarity of rumen microbiome functional community was higher in yak than cattle across seasons. Moreover, yak rumen microbiome encoded more genes (GH2 and GH3) related to cellulose and hemicellulose degradation compared to cattle, and a new enzyme family (GH160) gene involved in oligosaccharides was uniquely detected in yak rumen. The season affected microbiome attenuation and buffering values (stability), with higher buffering value in yak rumen microbiome than cattle. Positive correlations between antimicrobial resistance gene (dfrF) and CAZyme family (GH113) and microbiome stability were identified in yak, but such relationship was negatively correlated in cattle. CONCLUSIONS: The findings of the potential of cellulose degradation, the relationship between rumen microbial stability and the abundance of functional genes varied differently across seasons and between yak and cattle provide insight into the mechanisms that may underpin their divergent adaptation patterns to the harsh climate of the Qinghai-Tibetan Plateau. These results lay a solid foundation for developing strategies to maintain and improve rumen microbiome stability and dig out the potential candidates for manufacturing lignocellulolytic enzymes in the yak rumen to enhance ruminants' performance under extreme environmental conditions.


Asunto(s)
Microbioma Gastrointestinal , Rumen , Estaciones del Año , Animales , Bovinos , Rumen/microbiología , Microbioma Gastrointestinal/fisiología , Microbiota , Adaptación Fisiológica , Bacterias/genética , Bacterias/clasificación
4.
Med Res Rev ; 44(2): 707-737, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37983840

RESUMEN

The B-cell lymphoma-2 (BCL-2) family of proteins plays a crucial role in the regulation of apoptosis, offering a dual mechanism for its control. Numerous studies have established a strong association between gene disorders of these proteins and the proliferation of diverse cancer cell types. Consequently, the identification and development of drugs targeting BCL-2 family proteins have emerged as a prominent area in antitumor therapy. Over the last two decades, several small-molecules have been designed to modulate the protein-protein interactions between anti- and proapoptotic BCL-2 proteins, effectively suppressing tumor growth and metastasis in vivo. The primary focus of research has been on developing BCL-2 homology 3 (BH3) mimetics to target antiapoptotic BCL-2 proteins, thereby competitively releasing proapoptotic BCL-2 proteins and restoring the blocked intrinsic apoptotic program. Additionally, for proapoptotic BCL-2 proteins, exogenous small molecules have been explored to activate cell apoptosis by directly interacting with executioner proteins such as BCL-2-associated X protein (BAX) or BCL-2 homologous antagonist/killer protein (BAK). In this comprehensive review, we summarize the inhibitors and activators (sensitizers) of BCL-2 family proteins developed over the past decades, highlighting their discovery, optimization, preclinical and clinical status, and providing an overall landscape of drug development targeting these proteins for therapeutic purposes.


Asunto(s)
Neoplasias , Proteínas Proto-Oncogénicas , Humanos , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/farmacología , Proteína Destructora del Antagonista Homólogo bcl-2/genética , Proteína Destructora del Antagonista Homólogo bcl-2/metabolismo , Proteína Destructora del Antagonista Homólogo bcl-2/farmacología , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo , Proteína X Asociada a bcl-2/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Apoptosis , Neoplasias/tratamiento farmacológico
5.
Small ; 20(37): e2401673, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38721983

RESUMEN

One of the biggest challenges in biotechnology and medical diagnostics is finding extremely sensitive and adaptable biosensors. Since metal-based enzyme-mimetic biocatalysts may lead to biosafety concerns on accumulative toxicity, it is essential to synthesize metal-free enzyme-mimics with optimal biocatalytic activity and superior selectivity. Here, the pyridine-bridged covalent organic frameworks (COFs) with specific oxidase-like (OXD-like) activities as intelligent artificial enzymes for light-augmented biocatalytic sensing of biomarkers are disclosed. Because of the adjustable bandgaps of pyridine structures on the photocatalytic properties of the pristine COF structures, the pyridine-bridged COF exhibit efficient, selective, and light-responsive OXD-like biocatalytic activity. Moreover, the pyridine-bridged COF structures show tunable and light-augmented biocatalytic detection capabilities, which outperform the recently reported state-of-the-art OXD-mimics regarding biosensing efficiency. Notably, the pyridine-bridged COF exhibits efficient and multifaceted diagnostic activity, including the extremely low limit of detection (LOD), which enables visual assays for abundant reducibility biomarkers. It is believed that this design will offer unique metal-free biocatalysts for high-sensitive and low-cost colorimetric detection and also provide new insights to create highly efficient enzyme-like COF materials via linkage-modulation strategies for future biocatalytic applications.


Asunto(s)
Biocatálisis , Técnicas Biosensibles , Luz , Estructuras Metalorgánicas , Piridinas , Piridinas/química , Estructuras Metalorgánicas/química , Técnicas Biosensibles/métodos
6.
J Antimicrob Chemother ; 79(2): 447-452, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38153179

RESUMEN

OBJECTIVES: To characterize an Escherichia coli strain causing bloodstream infection encoding both high-virulence and carbapenem-resistance phenotypes. METHODS: Antimicrobial susceptibility testing, WGS and bioinformatics analysis were performed to characterize strain E1. The function of the ColV plasmid was investigated by the Galleria mellonella infection model, serum killing and macrophage killing assays. The fitness effect of the ColV plasmid was tested by growth curve, plasmid stability tests and the in vitro competition assay. The conjugation assay was performed to test the transferability of the ColV and blaNDM-5-carrying plasmids. RESULTS: E. coli E1 from bloodstream infection was MDR and highly virulent in the G. mellonella infection model. It belonged to phylogroup D, ST38 and serotype O7:H8. E1 carried a conjugatively transferable IncI1-type blaNDM-5-positive plasmid, which conferred carbapenem resistance, a conjugative IncFIB/FII-type ColV plasmid encoding an array of virulence-associated genes and antibiotic resistance genes blaTEM-1B, strAB and sul2, and seven other plasmids. Co-transfer of the ColV plasmid and the blaNDM-5-positive plasmid was observed. The ColV virulence-resistance hybrid plasmid contributed to the virulence, resistance to serum killing, and macrophage phagocytosis in E. coli E1. The carriage of this ColV plasmid did not constitute an in vitro fitness burden to strain E1 but caused fitness costs to E. coli strain EC600. CONCLUSIONS: The emergence of such a highly virulent and resistant strain with conjugative blaNDM-5-positive and ColV plasmids posed a significant threat to public health. Implementation of control measures is needed to prevent such strains from further disseminating in hospital settings and the community.


Asunto(s)
Infecciones por Escherichia coli , Sepsis , Humanos , Escherichia coli , Virulencia/genética , Carbapenémicos/farmacología , Plásmidos/genética , Antibacterianos/farmacología , beta-Lactamasas/genética , beta-Lactamasas/farmacología , Pruebas de Sensibilidad Microbiana
7.
J Transl Med ; 22(1): 723, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103875

RESUMEN

BACKGROUND: Inadequate nerve regeneration and an inhibitory local microenvironment are major obstacles to the repair of spinal cord injury (SCI). The activation and differentiation fate regulation of endogenous neural stem cells (NSCs) represent one of the most promising repair approaches. Metformin has been extensively studied for its antioxidative, anti-inflammatory, anti-aging, and autophagy-regulating properties in central nervous system diseases. However, the effects of metformin on endogenous NSCs remains to be elucidated. METHODS: The proliferation and differentiation abilities of NSCs were evaluated using CCK-8 assay, EdU/Ki67 staining and immunofluorescence staining. Changes in the expression of key proteins related to ferroptosis in NSCs were detected using Western Blot and immunofluorescence staining. The levels of reactive oxygen species, glutathione and tissue iron were measured using corresponding assay kits. Changes in mitochondrial morphology and membrane potential were observed using transmission electron microscopy and JC-1 fluorescence probe. Locomotor function recovery after SCI in rats was assessed through BBB score, LSS score, CatWalk gait analysis, and electrophysiological testing. The expression of the AMPK pathway was examined using Western Blot. RESULTS: Metformin promoted the proliferation and neuronal differentiation of NSCs both in vitro and in vivo. Furthermore, a ferroptosis model of NSCs using erastin treatment was established in vitro, and metformin treatment could reverse the changes in the expression of key ferroptosis-related proteins, increase glutathione synthesis, reduce reactive oxygen species production and improve mitochondrial membrane potential and morphology. Moreover, metformin administration improved locomotor function recovery and histological outcomes following SCI in rats. Notably, all the above beneficial effects of metformin were completely abolished upon addition of compound C, a specific inhibitor of AMP-activated protein kinase (AMPK). CONCLUSION: Metformin, driven by canonical AMPK-dependent regulation, promotes proliferation and neuronal differentiation of endogenous NSCs while inhibiting ferroptosis, thereby facilitating recovery of locomotor function following SCI. Our study further elucidates the protective mechanism of metformin in SCI, providing new mechanistic insights for its candidacy as a therapeutic agent for SCI.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Diferenciación Celular , Proliferación Celular , Ferroptosis , Metformina , Células-Madre Neurales , Ratas Sprague-Dawley , Traumatismos de la Médula Espinal , Metformina/farmacología , Traumatismos de la Médula Espinal/tratamiento farmacológico , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/metabolismo , Animales , Células-Madre Neurales/efectos de los fármacos , Células-Madre Neurales/metabolismo , Proliferación Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Ferroptosis/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Transducción de Señal/efectos de los fármacos , Ratas , Especies Reactivas de Oxígeno/metabolismo , Recuperación de la Función/efectos de los fármacos
8.
Magn Reson Med ; 91(5): 2126-2141, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38156813

RESUMEN

PURPOSE: Tensor-valued diffusion encoding can disentangle orientation dispersion and subvoxel anisotropy, potentially offering insight into microstructural changes after cerebral ischemia. The purpose was to evaluate tensor-valued diffusion MRI in human acute ischemic stroke, assess potential confounders from diffusion time dependencies, and compare to Monte Carlo diffusion simulations of axon beading. METHODS: Linear (LTE) and spherical (STE) b-tensor encoding with inherently different effective diffusion times were acquired in 21 acute ischemic stroke patients between 3 and 57 h post-onset at 3 T in 2.5 min. In an additional 10 patients, STE with 2 LTE yielding different effective diffusion times were acquired for comparison. Diffusional variance decomposition (DIVIDE) was used to estimate microscopic anisotropy (µFA), as well as anisotropic, isotropic, and total diffusional variance (MKA , MKI , MKT ). DIVIDE parameters, and diffusion tensor imaging (DTI)-derived mean diffusivity and fractional anisotropy (FA) were compared in lesion versus contralateral white matter. Monte Carlo diffusion simulations of various cylindrical geometries for all b-tensor protocols were used to interpret parameter measurements. RESULTS: MD was ˜40% lower in lesions for all LTE/STE protocols. The DIVIDE parameters varied with effective diffusion time: higher µFA and MKA in lesion versus contralateral white matter for STE with longer effective diffusion time LTE, whereas the shorter effective diffusion time LTE protocol yielded lower µFA and MKA in lesions. Both protocols, regardless of diffusion time, were consistent with simulations of greater beading amplitude and intracellular volume fraction. CONCLUSION: DIVIDE parameters depend on diffusion time in acute stroke but consistently indicate neurite beading and larger intracellular volume fraction.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Sustancia Blanca , Humanos , Imagen de Difusión Tensora/métodos , Accidente Cerebrovascular Isquémico/patología , Imagen de Difusión por Resonancia Magnética/métodos , Sustancia Blanca/patología , Accidente Cerebrovascular/diagnóstico por imagen , Anisotropía , Encéfalo/diagnóstico por imagen , Encéfalo/patología
9.
Opt Express ; 32(6): 9553-9561, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38571186

RESUMEN

A design method for ultrahigh-Q microring resonators (MRRs) based on Bezier free-form curves was proposed and demonstrated. An MRR consisting of a specially designed 180° waveguide bend, a directional coupler, and two low-loss multi-mode strip waveguides was designed. The free-form curves were used to increase the degree of freedom in the design, shaping the waveguide bend with a gradient width and curvature. This design effectively reduced the propagation loss caused by the roughness of waveguide sidewalls and the mode mismatch loss caused by the excitation of high order modes. The small effective radius of only 20µm enabled the MRR to have a large free spectral range (FSR) and a compact and flexible structure. The MRR was manufactured using a standard process provided by foundry and measured to have an ultrahigh loaded Q factor of 1.86 × 106 and a FSR of about 1 nm.

10.
Opt Lett ; 49(11): 3210-3213, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824365

RESUMEN

Recent advances in learning-based computer-generated holography (CGH) have unlocked novel possibilities for crafting phase-only holograms. However, existing approaches primarily focus on the learning ability of network modules, often neglecting the impact of diffraction propagation models. The resulting ringing artifacts, emanating from the Gibbs phenomenon in the propagation model, can degrade the quality of reconstructed holographic images. To this end, we explore a diffraction propagation error-compensation network that can be easily integrated into existing CGH methods. This network is designed to correct propagation errors by predicting residual values, thereby aligning the diffraction process closely with an ideal state and easing the learning burden of the network. Simulations and optical experiments demonstrate that our method, when applied to state-of-the-art HoloNet and CCNN, achieves PSNRs of up to 32.47 dB and 29.53 dB, respectively, surpassing baseline methods by 3.89 dB and 0.62 dB. Additionally, real-world experiments have confirmed a significant reduction in ringing artifacts. We envision this approach being applied to a variety of CGH algorithms, paving the way for improved holographic displays.

11.
Opt Lett ; 49(13): 3628-3631, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950226

RESUMEN

Real-time tracking and 3D trajectory computation of fast-moving objects is a promising technology, especially in the field of autonomous driving. However, existing image-based tracking methods face significant challenges when it comes to real-time tracking, primarily due to the limitation of storage space and computational resources. Here, we propose a novel approach that enables real-time 3D tracking of a fast-moving object without any prior motion information and at a very low computational cost. To enable 3D coordinate synthesis with a space-efficient optical setup, geometric moment patterns are projected on two non-orthogonal planes with a spatial resolution of 125 µm. Our experiment demonstrates an impressive tracking speed of 6667 frames per second (FPS) with a 20 kHz digital micromirror device (DMD), which is more than 200 times faster than the widely adopted video-based tracking methods. To the best of our knowledge, this is the highest tracking speed record in the field of single-pixel 3D trajectory tracking. This method promotes the development of real-time tracking techniques with single-pixel imaging (SPI).

12.
Opt Lett ; 49(3): 546-549, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300055

RESUMEN

Computer vision technology has been applied in various fields such as identification, surveillance, and robot vision. However, computer vision algorithms used for human-related tasks operate on human images, which raises data security and privacy concerns. In this Letter, we propose an image-free human keypoint detection technique using a few coded illuminations and a single-pixel detector. Our proposed method can complete the keypoint detection task at an ultralow sampling rate on a measured one-dimensional sequence without image reconstruction, thus protecting privacy from the data collection stage and preventing the acquisition of detailed visual information from the source. The network is designed to optimize both the illumination patterns and the human keypoint predictor with an encoder-decoder framework. For model training and validation, we used 2000 images from Leeds Sport Dataset and COCO Dataset. By incorporating EfficientNet backbone, the inference time is reduced from 4 s to 0.10 s. In the simulation, the proposed network achieves 91.7% average precision. Our experimental results show an average precision of 88.4% at a remarkably low sampling rate of 0.015. In summary, our proposed method has the advantages of privacy protection and resource efficiency, which can be applied to many monitoring and healthcare tasks, such as clinical monitoring, construction site monitoring, and home service robots.


Asunto(s)
Algoritmos , Privacidad , Humanos , Simulación por Computador , Procesamiento de Imagen Asistido por Computador , Iluminación
13.
Respir Res ; 25(1): 182, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664707

RESUMEN

OBJECTIVE: Asthma stands as one of the most prevalent chronic respiratory conditions in children, with its pathogenesis tied to the actived antigen presentation by dendritic cells (DCs) and the imbalance within T cell subgroups. This study seeks to investigate the role of the transcription factor EB (TFEB) in modulating the antigen presentation process of DCs and its impact on the differentiation of T cell subgroups. METHODS: Bone marrow dendritic cells (BMDCs) were activated using house dust mites (HDM) and underwent RNA sequencing (RNA-seq) to pinpoint differentially expressed genes. TFEB mRNA expression levels were assessed in the peripheral blood mononuclear cells (PBMCs) of both healthy children and those diagnosed with asthma. In an asthma mouse model induced by HDM, the TFEB expression in lung tissue DCs was evaluated. Further experiments involved LV-shTFEB BMDCs co-cultured with T cells to explore the influence of TFEB on DCs' antigen presentation, T cell subset differentiation, and cytokine production. RESULTS: Transcriptomic sequencing identified TFEB as a significantly differentially expressed gene associated with immune system pathways and antigen presentation. Notably, TFEB expression showed a significant increase in the PBMCs of children diagnosed with asthma compared to healthy counterparts. Moreover, TFEB exhibited heightened expression in lung tissue DCs of HDM-induced asthmatic mice and HDM-stimulated BMDCs. Silencing TFEB resulted in the downregulation of MHC II, CD80, CD86, and CD40 on DCs. This action reinstated the equilibrium among Th1/Th2 and Th17/Treg cell subgroups, suppressed the expression of pro-inflammatory cytokines like IL-4, IL-5, IL-13, and IL-17, while augmenting the expression of the anti-inflammatory cytokine IL-10. CONCLUSION: TFEB might have a vital role in asthma's development by impacting the antigen presentation of DCs, regulating T cell subgroup differentiation, and influencing cytokine secretion. Its involvement could be pivotal in rebalancing the immune system in asthma. These research findings could potentially unveil novel therapeutic avenues for treating asthma.


Asunto(s)
Presentación de Antígeno , Asma , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice , Células Dendríticas , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Asma/inmunología , Asma/metabolismo , Animales , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Ratones , Presentación de Antígeno/inmunología , Humanos , Niño , Femenino , Masculino , Células Cultivadas , Ratones Endogámicos BALB C
14.
Brain Behav Immun ; 120: 403-412, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38871062

RESUMEN

Persistent psychological stress can affect immune homeostasis and is a key factor in the development of depression. Many efforts are focused on the identifcation of pathways that link the immune system and mood disorders. Here, we found that psychological stress caused an increase in the frequency of brain-associated neutrophils and the level of neutrophil-specific antigen CD177 on peripheral neutrophils in male mice. Upregulated levels of blood CD177 are associated with depression in humans. Neutrophil depletion or Cd177 deficiency protected mice from stress-induced behavioral deficits. Importantly, adoptive transfer of CD177+ neutrophils from stressed mice increased the frequency of brain-associated leukocytes, including neutrophils, and caused behavioral defects in naive mice. These effects may be related to the endothelial adhesion advantage of CD177+ neutrophils and the interference of serine protease on endothelial junction. Our findings suggest a critical link between circulating CD177+ neutrophils and psychological stress-driven behavioral disorder.


Asunto(s)
Conducta Animal , Ratones Endogámicos C57BL , Neutrófilos , Estrés Psicológico , Animales , Humanos , Masculino , Ratones , Conducta Animal/fisiología , Encéfalo/metabolismo , Depresión/metabolismo , Depresión/inmunología , Proteínas Ligadas a GPI/metabolismo , Neutrófilos/metabolismo , Receptores de Superficie Celular/metabolismo , Estrés Psicológico/metabolismo , Estrés Psicológico/inmunología
15.
Eur Radiol ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143248

RESUMEN

OBJECTIVES: To explore diffusion-weighted imaging (DWI), intravoxel incoherent motion (IVIM), and diffusion kurtosis imaging (DKI) for assessing pathological prognostic factors in patients with rectal cancer. MATERIALS AND METHODS: A total of 162 patients (105 males; mean age of 61.8 ± 13.1 years old) scheduled to undergo radical surgery were enrolled in this prospective study. The pathological prognostic factors included histological differentiation, lymph node metastasis (LNM), and extramural vascular invasion (EMVI). The DWI, IVIM, and DKI parameters were obtained and correlated with prognostic factors using univariable and multivariable logistic regression. Their assessment value was evaluated using receiver operating characteristic (ROC) curve analysis. RESULTS: Multivariable logistic regression analyses showed that higher mean kurtosis (MK) (odds ratio (OR) = 194.931, p < 0.001) and lower apparent diffusion coefficient (ADC) (OR = 0.077, p = 0.025) were independently associated with poorer differentiation tumors. Higher perfusion fraction (f) (OR = 575.707, p = 0.023) and higher MK (OR = 173.559, p < 0.001) were independently associated with LNMs. Higher f (OR = 1036.116, p = 0.024), higher MK (OR = 253.629, p < 0.001), lower mean diffusivity (MD) (OR = 0.125, p = 0.038), and lower ADC (OR = 0.094, p = 0.022) were independently associated with EMVI. The area under the ROC curve (AUC) of MK for histological differentiation was significantly higher than ADC (0.771 vs. 0.638, p = 0.035). The AUC of MK for LNM positivity was higher than f (0.770 vs. 0.656, p = 0.048). The AUC of MK combined with MD (0.790) was the highest among f (0.663), MK (0.779), MD (0.617), and ADC (0.610) in assessing EMVI. CONCLUSION: The DKI parameters may be used as imaging biomarkers to assess pathological prognostic factors of rectal cancer before surgery. CLINICAL RELEVANCE STATEMENT: Diffusion kurtosis imaging (DKI) parameters, particularly mean kurtosis (MK), are promising biomarkers for assessing histological differentiation, lymph node metastasis, and extramural vascular invasion of rectal cancer. These findings suggest DKI's potential in the preoperative assessment of rectal cancer. KEY POINTS: Mean kurtosis outperformed the apparent diffusion coefficient in assessing histological differentiation in resectable rectal cancer. Perfusion fraction and mean kurtosis are independent indicators for assessing lymph node metastasis in rectal cancer. Mean kurtosis and mean diffusivity demonstrated superior accuracy in assessing extramural vascular invasion.

16.
Inflamm Res ; 73(5): 819-839, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38472395

RESUMEN

OBJECTIVE: This study aims to investigate the role of Acyl-CoA synthetase 4 (ACSL4) in mediating mitochondrial fatty acid metabolism and dendritic cell (DC) antigen presentation in the immune response associated with asthma. METHODS: RNA sequencing was employed to identify key genes associated with mitochondrial function and fatty acid metabolism in DCs. ELISA was employed to assess the levels of fatty acid metabolism in DCs. Mitochondrial morphology was evaluated using laser confocal microscopy, structured illumination microscopy, and transmission electron microscopy. Flow cytometry and immunofluorescence were utilized to detect changes in mitochondrial superoxide generation in DCs, followed by immunofluorescence co-localization analysis of ACSL4 and the mitochondrial marker protein COXIV. Subsequently, pathological changes and immune responses in mouse lung tissue were observed. ELISA was conducted to measure the levels of fatty acid metabolism in lung tissue DCs. qRT-PCR and western blotting were employed to respectively assess the expression levels of mitochondrial-associated genes (ATP5F1A, VDAC1, COXIV, TFAM, iNOS) and proteins (ATP5F1A, VDAC1, COXIV, TOMM20, iNOS) in lung tissue DCs. Flow cytometry was utilized to analyze changes in the expression of surface antigens presented by DCs in lung tissue, specifically the MHCII molecule and the co-stimulatory molecules CD80/86. RESULTS: The sequencing results reveal that ACSL4 is a crucial gene regulating mitochondrial function and fatty acid metabolism in DCs. Inhibiting ACSL4 reduces the levels of fatty acid oxidases in DCs, increases arachidonic acid levels, and decreases A-CoA synthesis. Simultaneously, ACSL4 inhibition leads to an increase in mitochondrial superoxide production (MitoSOX) in DCs, causing mitochondrial rupture, vacuolization, and sparse mitochondrial cristae. In mice, ACSL4 inhibition exacerbates pulmonary pathological changes and immune responses, reducing the fatty acid metabolism levels within lung tissue DCs and the expression of mitochondria-associated genes and proteins. This inhibition induces an increase in the expression of MHCII antigen presentation molecules and co-stimulatory molecules CD80/86 in DCs. CONCLUSIONS: The research findings indicate that ACSL4-mediated mitochondrial fatty acid metabolism and dendritic cell antigen presentation play a crucial regulatory role in the immune response of asthma. This discovery holds promise for enhancing our understanding of the mechanisms underlying asthma pathogenesis and potentially identifying novel targets for its prevention and treatment.


Asunto(s)
Presentación de Antígeno , Asma , Coenzima A Ligasas , Células Dendríticas , Ácidos Grasos , Mitocondrias , Animales , Femenino , Ratones , Asma/inmunología , Asma/metabolismo , Coenzima A Ligasas/metabolismo , Coenzima A Ligasas/genética , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Ácidos Grasos/metabolismo , Pulmón/inmunología , Pulmón/metabolismo , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Mitocondrias/metabolismo , Superóxidos/metabolismo
17.
Eur J Clin Microbiol Infect Dis ; 43(3): 617-622, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38228942

RESUMEN

To identify the phenotypic and genomic characteristics of K. pneumoniae KP43 from bloodstream infection. KP43 was resistant to ticarcillin and tetracycline and was hypervirulent in the Galleria mellonella larvae infection model, positive for string test, and possessed high-level macrophage killing resistance. The hypervirulence phenotype was associated with the chromosome integration of ICEKp1 carrying iroBCDN-iroP, rmpADC, and peg-344, and a novel plasmid pKP43_vir_amr harboring iutAiucABCD. pKP43_vir_amr was an IncFIBκ/FII virulence-resistance hybrid conjugative plasmid which also carried antibiotic resistance genes. The emergence of such a strain and the spread of the novel virulence-resistance plasmid might pose a potential threat to public health.


Asunto(s)
Infecciones por Klebsiella , Klebsiella pneumoniae , Animales , Humanos , Virulencia/genética , Klebsiella pneumoniae/genética , Infecciones por Klebsiella/microbiología , Plásmidos/genética , Antibacterianos/farmacología , Cromosomas , beta-Lactamasas/genética
18.
Macromol Rapid Commun ; 45(12): e2300715, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38539063

RESUMEN

The raw materials of Poly(ethylene terephthalate) (PET) are derived from petroleum-based resources, which are no sustainable. Therefore, previous researchers introduced biomass-derived 2,5-tetrahydrofurfuryl dimethanol (THFDM) into PET. However, its heat resistance has decreased compared to PET. In this paper, a novel bio-based copolyester, poly(ethylene glycol-co-2,5-tetrahydrofuran dimethanol-co-isosorbide terephthalate) (PEIFT), is prepared by introducing biomass-derived isosorbide (ISB) and THFDM into the PET chains through melting copolymerization process. With the introduction of ISB content, copolyesters' hydrophilicity and rigidity improve. Compared to PET, glass transition temperature (Tg) increases by over 5 °C. In addition, the toughness and spinning performance of PEIFT have also been improved as a result of the addition of THFDM components. The hydrophobicity of PEIFTs electrospinning is greatly improved, with a contact angle exceeding 135°. Finally, due to the good hydrophobicity of PEIFTs nanofibers, they have potential application value in the manufacture of hydrophobic nanofiber and filter films. Given its biomass source and excellent performance, they make it easier to replace materials derived from petroleum.


Asunto(s)
Interacciones Hidrofóbicas e Hidrofílicas , Nanofibras , Poliésteres , Nanofibras/química , Poliésteres/química , Poliésteres/síntesis química , Isosorbida/química , Biomasa , Tereftalatos Polietilenos/química , Furanos/química
19.
Cell Mol Biol (Noisy-le-grand) ; 70(4): 225-230, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38678600

RESUMEN

This study compared the therapeutic effect and safety between warfarin anticoagulation and percutaneous left atrial appendage transcatheter occlusion (PLAATO) in non-valvular atrial fibrillation (NVAF). A total of 110 patients were selected and assigned to Control group (n=55) and Observation group (n=55). The control patients were used warfarin, while the observation patients were performed PLAATO. The coagulation function, stroke and bleeding scores were compared between the two groups at different times. Left ventricular function before therapy and 1 year after therapy and adverse events during follow-up were compared between the two groups. After one month of treatment, CHA2DS2-VASC, HAS-BLED score, serum ET-1 and hs-CRP levels were lower in the PLAATO patients than in warfarin patients, but serum PDGFs levels were higher than patients in the warfarin patients (P < 0.05). One month after treatment, the activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT) of the PLAATO patients was longer than that of the warfarin patients (P < 0.05), but the levels of fibrinogen (FIB) in the PLAATO patients were lower than that of the warfarin patients (P < 0.05). In addition, one year after therapy, the left atrial end-diastolic volume (LAEDV), left atrial end-systolic volume (LAESV) and left atrial inner diameter of the two groups were significantly reduced (P < 0.05). Left atrial appendage (LAA) occlusion can effectively improve the cardiac function and coagulation function of NVAF patients, with lower incidence of bleeding events, stroke events and higher safety.


Asunto(s)
Anticoagulantes , Fibrilación Atrial , Coagulación Sanguínea , Cierre del Apéndice Auricular Izquierdo , Warfarina , Warfarina/efectos adversos , Warfarina/farmacología , Anticoagulantes/efectos adversos , Anticoagulantes/farmacología , Fibrilación Atrial/sangre , Fibrilación Atrial/terapia , Apéndice Atrial/fisiopatología , Accidente Cerebrovascular/etiología , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Hemorragia/etiología , Tiempo de Tromboplastina Parcial , Tiempo de Protrombina , Tiempo de Trombina , Coagulación Sanguínea/efectos de los fármacos , Endotelina-1/sangre , Proteína C-Reactiva/análisis
20.
BMC Cardiovasc Disord ; 24(1): 597, 2024 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-39462356

RESUMEN

BACKGROUND: To clarify the fat attenuation index (FAI) change trend of peri-saphenous vein graft (SVG) and determine the association between FAI and graft disease progression based on CCTA images. METHODS: Patients with venous coronary artery bypass grafts (CABGs) were consecutively enrolled in this retrospective study. In study 1, 72 patients who had undergone 1, 3, and 5 years of CCTA examinations without graft occlusion were recruited, and generalized estimation equation was used to analyze the peri-SVG FAI change trend over time. In study 2, 42 patients with graft disease progression and 84 patients as controls were propensity score-matched. Generalized linear mixed model and continuous net reclassification improvement (NRI) were used for assessing the associations with graft disease progression. Multivariable Cox regression analysis was used for assessing risk factors predicting cardiac events. RESULTS: In study 1, both the FAI of proximal right coronary artery and SVG decreased over time. In study 2, the 1-year CTA-derived FAI of grafts and graft anastomosis were independent indicators of graft disease progression at the 3-year CCTA follow-up (graft: odds ratio [OR] = 1.106; 95% confidence interval [CI] = 1.030-1.188, P = 0.006; graft anastomosis: OR = 1.170, 95% CI = 1.091-1.254, P < 0.001). Inclusion of the graft anastomosis FAI significantly improved reclassification compared with graft FAI (continuous NRI = 0.638, 95% CI: 0.345-0.931, P < 0.001). Moreover, The graft anastomosis FAI was found to be a risk factor for cardiac events after CABG and no statistically significant difference was found in the graft FAI (graft anastomosis: HR = 1.158, 95% CI = 1.034-1.297, P = 0.011; graft: HR = 1.116, 95% CI = 0.995-1.251, P = 0.061). CONCLUSIONS: A synchronism was found in the FAI change trend between native coronary artery and venous graft, which both decreased over time. The CCTA-derived FAI of venous grafts showed the potential of demonstrating SVG disease progression and graft anastomosis served as the optimal measured location.


Asunto(s)
Angiografía por Tomografía Computarizada , Angiografía Coronaria , Puente de Arteria Coronaria , Enfermedad de la Arteria Coronaria , Progresión de la Enfermedad , Oclusión de Injerto Vascular , Valor Predictivo de las Pruebas , Vena Safena , Humanos , Masculino , Femenino , Puente de Arteria Coronaria/efectos adversos , Puente de Arteria Coronaria/tendencias , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , Factores de Tiempo , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/cirugía , Vena Safena/trasplante , Vena Safena/diagnóstico por imagen , Oclusión de Injerto Vascular/etiología , Oclusión de Injerto Vascular/diagnóstico por imagen , Oclusión de Injerto Vascular/fisiopatología , Resultado del Tratamiento , Factores de Riesgo , Tejido Adiposo/diagnóstico por imagen , Tejido Adiposo/trasplante , Medición de Riesgo
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