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During influenza A virus infection, the viral RNA polymerase transcribes the viral negative-sense segmented RNA genome and replicates it in a two-step process via complementary RNA within viral ribonucleoprotein (vRNP) complexes. While numerous viral and host factors involved in vRNP functions have been identified, dissecting the roles of individual factors remains challenging due to the complex cellular environment in which vRNP activity has been studied. To overcome this challenge, we reconstituted viral transcription and a full cycle of replication in a test tube using vRNPs isolated from virions and recombinant factors essential for these processes. This novel system uncovers the minimal components required for influenza virus replication and also reveals new roles of regulatory factors in viral replication. Moreover, it sheds light on the molecular interplay underlying the temporal regulation of viral transcription and replication. Our highly robust in vitro system enables systematic functional analysis of factors modulating influenza virus vRNP activity and paves the way for imaging key steps of viral transcription and replication.
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Virus de la Influenza A , Gripe Humana , Orthomyxoviridae , Humanos , Virus de la Influenza A/genética , Gripe Humana/genética , Proteínas Virales/genética , Proteínas Virales/metabolismo , Ribonucleoproteínas/genética , Replicación Viral/fisiología , ARN Viral/genéticaRESUMEN
The pathophysiology of atopic dermatitis (AD) is complex. CD4+ T cells play an essential role in the development of lesions in AD. However, the underlying mechanism remains unclear. In the present study, we investigated the differentially expressed genes (DEGs) between adult AD lesioned and non-lesioned skin using two datasets from the Gene Expression Omnibus (GEO) database. 62 DEGs were shown to be related to cytokine response. Compared to non-lesioned skin, lesioned skin showed immune infiltration with increased numbers of activated natural killer (NK) cells and CD4+ T memory cells (p < 0.01). We then identified 13 hub genes with a strong association with CD4+ T cells using weighted correlation network analysis. Single-cell analysis of AD detected a novel CD4+ T subcluster, CD4+ tissue residency memory cells (TRMs), which were verified through immunohistochemistry (IHC) to be increased in the dermal area of AD. The significant relationship between CD4+ TRM and AD was assessed through further analyses. FOXO1 and SBNO2, two of the 13 hub genes, were characteristically expressed in the CD4+ TRM, but down-regulated in IFN-γ/TNF-α-induced HaCaT cells, as shown using quantitative polymerase chain reaction (qPCR). Moreover, SBNO2 expression was associated with increased Th1 infiltration in AD (p < 0.05). In addition, genes filtered using Mendelian randomization were positively correlated with CD4+ TRM and were highly expressed in IFN-γ/TNF-α-induced HaCaT cells, as determined using qPCR and western blotting. Collectively, our results revealed that the newly identified CD4+ TRM may be involved in the pathogenesis of adult AD.
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Linfocitos T CD4-Positivos , Dermatitis Atópica , Análisis de la Célula Individual , Dermatitis Atópica/genética , Dermatitis Atópica/metabolismo , Dermatitis Atópica/inmunología , Dermatitis Atópica/patología , Humanos , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/inmunología , Adulto , Células T de Memoria/metabolismo , Células T de Memoria/inmunología , Piel/metabolismo , Células HaCaT , Memoria Inmunológica , Masculino , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismoRESUMEN
Evaluating the ecosystem health of riparian zones is helpful for decision-makers to formulate appropriate management measures. However, there are few methods for such evaluation which account for both the human requirements and ecological aspects of riparian zones. To address this, we created a Pressure-State(Vigor-Organization-Resilience)-Response framework for evaluating the ecosystem health of the riparian zone of the Yangtze River in Jiangsu Province, a region experiencing intense land use changes. Evaluation indicators, including land use change and ecosystem services, were selected. The comprehensive index method was used to calculate the evaluation indicators of ecosystem health, namely pressure, state, and response, and the comprehensive evaluation indicator itself. Using the cold and hot spot analysis, we also analyzed the spatial heterogeneity of ecosystem health in the riparian zone, constructed an ecological management pattern, and proposed corresponding management and protection measures. The results show that (1) from 2010 to 2020, construction land in the study area increased by more than 20%, and all studied land types underwent some degree of conversion to construction land, with cultivated land and water bodies being the main focus of conversion. (2) In 2020, the average ecosystem health in the riparian zone was normal, with a spatial distribution characterized by "high dispersion and low clustering"; and (3) according to the results of the ecosystem health evaluation and cold and hot spot analysis, key areas for stronger ecological protection were identified and, based on this, a number of management recommendations were proposed.
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Ecosistema , Ríos , Humanos , Monitoreo del Ambiente , China , Conservación de los Recursos Naturales/métodosRESUMEN
The metabolic cross-talk between tumor and immune cells plays key roles in immune cell function and immune checkpoint blockade therapy. However, the characterization of tumor immunometabolism and its spatiotemporal alterations during immune response in a complex tumor microenvironment is challenging. Here, a 3D tumor-immune cell coculture spheroid model was developed to mimic tumor-immune interactions, combined with mass spectrometry imaging-based spatially resolved metabolomics to visualize tumor immunometabolic alterations during immune response. The inhibition of T cells was simulated by coculturing breast tumor spheroids with Jurkat T cells, and the reactivation of T cells can be monitored through diminishing cancer PD-L1 expressions by berberine. This system enables simultaneously screening and imaging discriminatory metabolites that are altered during T cell-mediated antitumor immune response and characterizing the distributions of berberine and its metabolites in tumor spheroids. We discovered that the transport and catabolism of glutamine were significantly reprogrammed during the antitumor immune response at both metabolite and enzyme levels, corresponding to its indispensable roles in energy metabolism and building new biomass. The combination of spatially resolved metabolomics with the 3D tumor-immune cell coculture spheroid visually reveals metabolic interactions between tumor and immune cells and possibly helps decipher the role of immunometabolic alterations in tumor immunotherapy.
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Berberina , Neoplasias , Humanos , Técnicas de Cocultivo , Neoplasias/patología , Esferoides Celulares/patología , Inmunidad , Microambiente TumoralRESUMEN
Short-chain fatty acids (SCFAs), as the main metabolites of gut microbiota, are recognized as crucial players in the host's inflammatory response and metabolic disease. Imaging the spatial distributions and calculating the accurate contents of SCFAs in the heterogeneous intestinal tissue are critical to reveal their biological functions. Here, we develop an isotope-coded on-tissue derivatization method combined with matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) to map the spatial expressions of SCFAs in the colon tissue based on pair-labeled N,N,N-trimethyl-2-(piperazin-1-yl)ethan-1-aminium iodide (TMPA) and D3-TMPA. A noticeable increase in the MALDI-MSI sensitivity of SCFAs was achieved after on-tissue derivatization, which enables the visualization of acetic acid, propionic acid, butyric acid, valeric acid, hexanoic acid, hydroxy acetic acid, and hydroxy propionic acid in the colon tissue. Moreover, the introduction of D3-TMPA-tagged SCFAs as internal standards can significantly reduce quantitation deviation from the matrix effects, ensuring the quantitative MALDI-MSI of SCFAs. We further used this method to characterize the spatial alterations of SCFAs in the colon tissues of mice with enterocolitis. The development of this strategy provides a reliable approach to image the spatial expressions of SCFAs in tissues and paves an insight way to study the roles of SCFAs in the gut microbiota and disease.
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Ácidos Grasos Volátiles , Propionatos , Ratones , Animales , Ácidos Grasos Volátiles/análisis , Ácido Acético , Isótopos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Ácido ButíricoRESUMEN
In the context of COVID-19, the research on various aspects of the venipuncture robot field has become increasingly hot, but there has been little research on robotic needle insertion angles, primarily performed at a rough angle. This will increase the rate of puncture failure. Furthermore, there is sometimes significant pain due to the patients' differences. This paper investigates the optimal needle entry angle decision for a dorsal hand intravenous injection robot. The dorsal plane of the hand was obtained by a linear structured light scan, which was used as a basis for calculating the needle entry angle. Simulation experiments were also designed to determine the optimal needle entry angle. Firstly, the linear structured optical system was calibrated and optimized, and the error function was constructed and solved iteratively by the optimization method to eliminate measurement error. Besides, the dorsal hand was scanned to obtain the spatial point clouds of the needle entry area, and the least squares method was used to fit it to obtain the dorsal hand plane. Then, the needle entry angle was calculated based on the needle entry area plane. Finally, the changes in the penetration force under different needle entry angles were analyzed to determine the optimal needle insertion angle. According to the experimental results, the average error of the optimized structured light plane position was about 0.1 mm, which meets the needs of the project, and a large angle should be properly selected for needle insertion during the intravenous injection.
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COVID-19 , Robótica , Humanos , Agujas , Punciones , DolorRESUMEN
BiOI/ZnO/rGO (reduced graphene oxide) composite photocatalyst was fabricated using a simple one-step hydrothermal process and applied to the degradation of antibiotic chloramphenicol (CAP). By tuning the Bi/Zn ratios, the structure and photoelectric properties of the catalyst were investigated and characterized in terms of their morphological, structural, optical and photoelectrochemical properties. The as-synthesized composite photocatalysts are well-crystalline, uniform dispersion and exhibit good photocatalytic properties. The photocatalytic degradation rate of CAP by BiOI/ZnO/rGO composite is 8.1 times and 1.8 times that of BiOI and ZnO, respectively. The photocatalytic mechanism studies revealed that the synergistic effect between rGO and BiOI/ZnO can effectively separate photogenerated electron-hole, enhance photocurrents and conductivity, and improve charge carrier densities. Moreover, BiOI/ZnO/rGO possesses good stability and reusability that the degradation efficiency remained above 80% even after 5 recycling. This study reveals that both the introduction of rGO and heterostructure construction between BiOI and ZnO play a crucial role in their photoelectrochemical and photocatalytic properties.
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Antibacterianos , Óxido de Zinc , Cloranfenicol , LuzRESUMEN
Intestinal barrier dysfunction and intestinal inflammation interact in the progression of Crohn's disease (CD). A recent study indicated that Epac-2 protected the intestinal barrier and had anti-inflammatory effects. The present study examined the function of Epac-2 in CD-like colitis. Interleukin-10 gene knockout (Il-10-/- ) mice exhibit significant spontaneous enteritis and were used as the CD model. These mice were treated with Epac-2 agonists (Me-cAMP) or Epac-2 antagonists (HJC-0350) or were fed normally (control), and colitis and intestinal barrier structure and function were compared. A Caco-2 and RAW 264.7 cell co-culture system were used to analyse the effects of Epac-2 on the cross-talk between intestinal epithelial cells and inflammatory cells. Epac-2 activation significantly ameliorated colitis in mice, which was indicated by reductions in the colitis inflammation score, the expression of inflammatory factors and intestinal permeability. Epac-2 activation also decreased Caco-2 cell permeability in an LPS-induced cell co-culture system. Epac-2 activation significantly suppressed nuclear factor (NF)-κB/mitogen-activated protein kinase (MAPK) signalling in vivo and in vitro. Epac-2 may be a therapeutic target for CD based on its anti-inflammatory functions and protective effects on the intestinal barrier.
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Colitis , Interleucina-10 , Animales , Células CACO-2 , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/genética , Factores de Intercambio de Guanina Nucleótido/genética , Factores de Intercambio de Guanina Nucleótido/metabolismo , Humanos , Interleucina-10/metabolismo , Mucosa Intestinal/metabolismo , Ratones , Ratones Endogámicos C57BL , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismoRESUMEN
PURPOSE: To use fiducial markers containing manganese 55 to rapidly localize carbon 13 (13 C) RF coils for correcting images for B1 variation. METHODS: Hollow high-density polyethylene spheres were filled with 3M sodium permanganate and affixed to a rectangular 13 C-tuned RF coil. The relative positions of the markers and coil conductors were mapped using CT. Marker positions were measured by MRI using a series of 1D projections and automated peak detection. Once the coil location was determined, coil sensitivity was estimated using a quasi-static calculation. Simulations were performed to determine the minimum number of projections required for robust localization. Phantom experiments were used to confirm the accuracy of marker localization as well as the calculated coil sensitivity. Finally, in vivo validation was performed using hyperpolarized 13 C pyruvate in a rat model. RESULTS: In simulations, our algorithm was accurate in determining marker positions when at least 6 projections were used (RMSE 1.4 ± 0.9 mm). These estimates were verified in phantom experiments, where markers locations were determined with an RMS accuracy of 1.3 mm. A minimum SNR of 4 was required for automated detection to perform accurately. Computed coil sensitivity had a median error of 17% when taken over the entire measured area and 5.7% over a central region. In a rat, correction for nonuniform reception and flip angle was able to normalize the signals arising from asymmetrically positioned kidneys. CONCLUSION: Manganese 55 fiducial markers are an inexpensive and reliable method for rapidly localizing 13 C RF coils and correcting 13 C images for B1 variation without user intervention.
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Marcadores Fiduciales , Imagen por Resonancia Magnética , Algoritmos , Animales , Fantasmas de Imagen , Ondas de Radio , RatasRESUMEN
PURPOSE: To develop a novel post-processing pipeline for hyperpolarized (HP) 13 C MRSI that integrates tensor denoising and B1+ correction to measure pyruvate-to-lactate conversion rates (kPL ) in patients with liver tumors. METHODS: Seven HP 13 C MR scans of progressing liver tumors were acquired using a custom 13 C surface transmit/receive coil and the echo-planar spectroscopic imaging (EPSI) data analysis included B0 correction, tensor rank truncation, and zero- and first-order phase corrections to recover metabolite signals that would otherwise be obscured by spectral noise as well as a correction for inhomogeneous transmit ( B1+ ) using a B1+ map aligned to the coil position for each patient scan. Processed HP data and corrected flip angles were analyzed with an inputless two-site exchange model to calculate kPL . RESULTS: Denoising averages SNR increases of pyruvate, lactate, and alanine were 37.4-, 34.0-, and 20.1-fold, respectively, with lactate and alanine dynamics most noticeably recovered and better defined. In agreement with Monte Carlo simulations, over-flipped regions underestimated kPL and under-flipped regions overestimated kPL . B1+ correction addressed this issue. CONCLUSION: The new HP 13 C EPSI post-processing pipeline integrated tensor denoising and B1+ correction to measure kPL in patients with liver tumors. These technical developments not only recovered metabolite signals in voxels that did not receive the prescribed flip angle, but also increased the extent and accuracy of kPL estimations throughout the tumor and adjacent regions including normal-appearing tissue and additional lesions.
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Neoplasias Hepáticas , Imagen por Resonancia Magnética , Isótopos de Carbono , Imagen Eco-Planar , Humanos , Cinética , Neoplasias Hepáticas/diagnóstico por imagen , Ácido PirúvicoRESUMEN
Enzymes immobilized in metal-organic frameworks (MOFs) have attracted great attention as a promising hybrid material. In the study, a novel biomimetic mineralization encapsulation process for a highly stable and easily reusable catalase (CAT)@ZIF-8 composite has been designed. This immobilization process provides a high enzyme loading of 70 wt %. The CAT@ZIF-8 composites exhibited a much lower Km value and better enzyme activity than those of free CAT, exhibiting good stability against enzymatic hydrolysis and protein denaturation under harsh conditions. The inhibitory effects of pesticides such as pH, temperature, solvent (i.e., methanol, dimethyl sulfoxide and tetrahydrofuran) and storage at room temperature (6 months) on the activity of free and immobilized catalase enzyme were investigated. The CAT@MOF composites also exhibited excellent reusability, an obvious advantage for treating a wastewater from food processing. The CAT@MOF developed is promising for the efficient removal of H2O2 under harsh conditions.
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Biocatálisis , Materiales Biomiméticos/química , Catalasa/química , Peróxido de Hidrógeno/químicaRESUMEN
Great deal pathogenic bacteria and malodorous gases are hidden in municipal solid waste (MSW), which poses excellent environmental sanitation risks for sanitation workers and residents, and preventive measures should be implemented. In this study, the simultaneous annihilation of microorganisms and volatile organic compounds (VOCs) with slightly acidic electrolyzed water (SAEW) was investigated in an MSW storage room of a residential community in Shanghai, China. The microbial population of airborne, surfaces and handles of waste bins, hands of sanitation workers and the main components of VOCs were measured. The results indicated that the bacterial reduction efficiencies of SAEW with an available chlorine concentration (ACC) of 50-100 mg/L on surfaces and handles of waste bins and sanitation workers' hands were 22.7%-84.1%. Also, SAEW effectively reduced the average population of airborne bacteria and fungi by 358 and 378 colony-forming units (CFU)/m3 and decreased the detection rates of coliforms by 14.2%-51.9%. The concentrations of most VOCs were reduced by 21.4%-88.3% after spraying SAEW. And the accumulated values of carcinogenic and noncarcinogenic risks also tended to decrease with spraying SAEW. These findings imply that SAEW has significant application potential to control environmental sanitation risks in MSW storage rooms.
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Desinfectantes , Compuestos Orgánicos Volátiles , China , Desinfección , Humanos , Residuos Sólidos , AguaRESUMEN
Viral infection of cells is sensed by pathogen recognition receptors that trigger an antiviral innate immune response, and consequently viruses have evolved countermeasures. Vaccinia virus (VACV) evades the host immune response by expressing scores of immunomodulatory proteins. One family of VACV proteins are the BTB-BACK (broad-complex, tram-trac, and bric-a-brac [BTB] and C-terminal Kelch [BACK]) domain-containing, Kelch-like (BBK) family of predicted cullin-3 E3 ligase adaptors: A55, C2, and F3. Previous studies demonstrated that gene A55R encodes a protein that is nonessential for VACV replication yet affects viral virulence in vivo Here, we report that A55 is an NF-κB inhibitor acting downstream of IκBα degradation, preventing gene transcription and cytokine secretion in response to cytokine stimulation. A55 targets the host importin α1 (KPNA2), acting to reduce p65 binding and its nuclear translocation. Interestingly, while A55 was confirmed to coprecipitate with cullin-3 in a BTB-dependent manner, its NF-κB inhibitory activity mapped to the Kelch domain, which alone is sufficient to coprecipitate with KPNA2 and inhibit NF-κB signaling. Intradermal infection of mice with a virus lacking A55R (vΔA55) increased VACV-specific CD8+ T-cell proliferation, activation, and cytotoxicity in comparison to levels of the wild-type (WT) virus. Furthermore, immunization with vΔA55 induced increased protection to intranasal VACV challenge compared to the level with control viruses. In summary, this report describes the first target of a poxvirus-encoded BBK protein and a novel mechanism for DNA virus immune evasion, resulting in increased CD8+ T-cell memory and a more immunogenic vaccine.IMPORTANCE NF-κB is a critical transcription factor in the innate immune response to infection and in shaping adaptive immunity. The identification of host and virus proteins that modulate the induction of immunological memory is important for improving virus-based vaccine design and efficacy. In viruses, the expression of BTB-BACK Kelch-like (BBK) proteins is restricted to poxviruses and conserved within them, indicating the importance of these proteins for these medically important viruses. Using vaccinia virus (VACV), the smallpox vaccine, we report that the VACV BBK protein A55 dysregulates NF-κB signaling by disrupting the p65-importin interaction, thus preventing NF-κB translocation and blocking NF-κB-dependent gene transcription. Infection with VACV lacking A55 induces increased VACV-specific CD8+ T-cell memory and better protection against VACV challenge. Studying viral immunomodulators therefore expands not only our understanding of viral pathogenesis and immune evasion strategies but also of the immune signaling cascades controlling antiviral immunity and the development of immune memory.
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Evasión Inmune/fisiología , FN-kappa B/antagonistas & inhibidores , Virus Vaccinia/metabolismo , Animales , Dominio BTB-POZ , Línea Celular , Proteínas Cullin/metabolismo , Femenino , Células HEK293 , Humanos , Inmunidad Innata , Carioferinas/metabolismo , Secuencia Kelch/fisiología , Ratones , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Poxviridae/metabolismo , Transducción de Señal , Linfocitos T/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Vaccinia/virología , Proteínas Virales/metabolismo , Virulencia , Replicación Viral/fisiología , alfa Carioferinas/metabolismoRESUMEN
PURPOSE: Acquisition timing and B1 calibration are two key factors that affect the quality and accuracy of hyperpolarized 13 C MRI. The goal of this project was to develop a new approach using regional bolus tracking to trigger Bloch-Siegert B1 mapping and real-time B1 calibration based on regional B1 measurements, followed by dynamic imaging of hyperpolarized 13 C metabolites in vivo. METHODS: The proposed approach was implemented on a system which allows real-time data processing and real-time control on the sequence. Real-time center frequency calibration upon the bolus arrival was also added. The feasibility of applying the proposed framework for in vivo hyperpolarized 13 C imaging was tested on healthy rats, tumor-bearing mice and a healthy volunteer on a clinical 3T scanner following hyperpolarized [1-13 C]pyruvate injection. Multichannel receive coils were used in the human study. RESULTS: Automatic acquisition timing based on either regional bolus peak or bolus arrival was achieved with the proposed framework. Reduced blurring artifacts in real-time reconstructed images were observed with real-time center frequency calibration. Real-time computed B1 scaling factors agreed with real-time acquired B1 maps. Flip angle correction using B1 maps results in a more consistent quantification of metabolic activity (i.e, pyruvate-to-lactate conversion, kPL ). Experiment recordings are provided to demonstrate the real-time actions during the experiment. CONCLUSIONS: The proposed method was successfully demonstrated on animals and a human volunteer, and is anticipated to improve the efficient use of the hyperpolarized signal as well as the accuracy and robustness of hyperpolarized 13 C imaging.
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Isótopos de Carbono/química , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética , Adulto , Algoritmos , Animales , Mapeo Encefálico , Calibración , Modelos Animales de Enfermedad , Voluntarios Sanos , Humanos , Masculino , Ratones , Trasplante de Neoplasias , Distribución Normal , Reconocimiento de Normas Patrones Automatizadas , Neoplasias de la Próstata/diagnóstico por imagen , Ácido Pirúvico , RatasRESUMEN
PURPOSE: The purpose of this study was to investigate (13) C hyperpolarization of α-ketobutyrate (αKB), an endogenous molecular analog of pyruvate, and its in vivo enzymatic conversion via lactate dehydrogenase (LDH) using localized MR spectroscopy. METHODS: Hyperpolarized (HP) (13) C MR experiments were conducted using [(13) C]αKB with rats in vivo and with isolated LDH enzyme in vitro, along with comparative experiments using [(13) C]pyruvate. Based on differences in the kinetics of its reaction with individual LDH isoforms, HP [(13) C]αKB was investigated as a novel MR probe, with added specificity for activity of LDHB-expressed H ("heart"-type) subunits of LDH (e.g., constituents of LDH-1 isoform). RESULTS: Comparable T1 and polarization values to pyruvate were attained (T1 = 52 s at 3 tesla [T], polarization = 10%, at C1 ). MR experiments showed rapid enzymatic conversion with substantially increased specificity. Formation of product HP [(13) C]α-hydroxybutyrate (αHB) from αKB in vivo was increased 2.7-fold in cardiac slabs relative to liver and kidney slabs. In vitro studies resulted in 5.0-fold higher product production from αKB with bovine heart LDH-1, as compared with pyruvate. CONCLUSIONS: HP [(13) C]αKB may be a useful MR probe of cardiac metabolism and other applications where the role of H subunits of LDH is significant (e.g., renal cortex and brain).
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Butiratos/química , Isótopos de Carbono/química , L-Lactato Deshidrogenasa/química , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Ácido Pirúvico/química , Animales , Bovinos , Riñón/enzimología , Cinética , Hígado/enzimología , Músculos/enzimología , Miocardio/enzimología , Oxidación-Reducción , Isoformas de Proteínas/química , ConejosRESUMEN
α-dystroglycan is a highly O-glycosylated extracellular matrix receptor that is required for anchoring of the basement membrane to the cell surface and for the entry of Old World arenaviruses into cells. Like-acetylglucosaminyltransferase (LARGE) is a key molecule that binds to the N-terminal domain of α-dystroglycan and attaches ligand-binding moieties to phosphorylated O-mannose on α-dystroglycan. Here we show that the LARGE modification required for laminin- and virus-binding occurs on specific Thr residues located at the extreme N terminus of the mucin-like domain of α-dystroglycan. Deletion and mutation analyses demonstrate that the ligand-binding activity of α-dystroglycan is conferred primarily by LARGE modification at Thr-317 and -319, within the highly conserved first 18 amino acids of the mucin-like domain. The importance of these paired residues in laminin-binding and clustering activity on myoblasts and in arenavirus cell entry is confirmed by mutational analysis with full-length dystroglycan. We further demonstrate that a sequence of five amino acids, Thr(317)ProThr(319)ProVal, contains phosphorylated O-glycosylation and, when modified by LARGE is sufficient for laminin-binding. Because the N-terminal region adjacent to the paired Thr residues is removed during posttranslational maturation of dystroglycan, our results demonstrate that the ligand-binding activity resides at the extreme N terminus of mature α-dystroglycan and is crucial for α-dystroglycan to coordinate the assembly of extracellular matrix proteins and to bind arenaviruses on the cell surface.
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Infecciones por Arenaviridae/etiología , Infecciones por Arenaviridae/metabolismo , Distroglicanos/metabolismo , Laminina/metabolismo , Virus de la Coriomeningitis Linfocítica , N-Acetilglucosaminiltransferasas/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Línea Celular , Distroglicanos/química , Distroglicanos/genética , Glicosilación , Células HEK293 , Humanos , Virus de la Coriomeningitis Linfocítica/patogenicidad , Ratones , Modelos Biológicos , Datos de Secuencia Molecular , Mutagénesis , Mioblastos/metabolismo , Fosforilación , Unión Proteica , Procesamiento Proteico-Postraduccional , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Treonina/química , Internalización del VirusRESUMEN
RNA editing, as an epigenetic mechanism, exhibits a strong correlation with the occurrence and development of cancers. Nevertheless, few studies have been conducted to investigate the impact of RNA editing on cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC). In order to study the connection between RNA editing and CESC patients' prognoses, we obtained CESC-related information from The Cancer Genome Atlas (TCGA) database and randomly allocated the patients into the training group or testing group. An RNA editing-based risk model for CESC patients was established by Cox regression analysis and least absolute shrinkage and selection operator (LASSO). According to the median score generated by this RNA editing-based risk model, patients were categorized into subgroups with high and low risks. We further constructed the nomogram by risk scores and clinical characteristics and analyzed the impact of RNA editing levels on host gene expression levels and adenosine deaminase acting on RNA. Finally, we also compared the biological functions and pathways of differentially expressed genes (DEGs) between different subgroups by enrichment analysis. In this risk model, we screened out 6 RNA editing sites with significant prognostic value. The constructed nomogram performed well in forecasting patients' prognoses. Furthermore, the level of RNA editing at the prognostic site exhibited a strong correlation with host gene expression. In the high-risk subgroup, we observed multiple biological functions and pathways associated with immune response, cell proliferation, and tumor progression. This study establishes an RNA editing-based risk model that helps forecast patients' prognoses and offers a new understanding of the underlying mechanism of RNA editing in CESC.
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Nomogramas , Edición de ARN , Neoplasias del Cuello Uterino , Humanos , Neoplasias del Cuello Uterino/genética , Femenino , Edición de ARN/genética , Pronóstico , Medición de Riesgo/métodos , Persona de Mediana Edad , Carcinoma de Células Escamosas/genética , Adenocarcinoma/genética , Adenosina Desaminasa/genéticaRESUMEN
This review compiles information from the literature on the chemical composition, pharmacological effects, and molecular mechanisms of earthworm extract (EE) and suggests possibilities for clinical translation of EE. We also consider future trends and concerns in this domain. We summarize the bioactive components of EE, including G-90, lysenin, lumbrokinase, antimicrobial peptides, earthworm serine protease (ESP), and polyphenols, and detail the antitumor, antithrombotic, antiviral, antibacterial, anti-inflammatory, analgesic, antioxidant, wound-healing, antifibrotic, and hypoglycemic activities and mechanisms of action of EE based on existing in vitro and in vivo studies. We further propose the potential of EE for clinical translation in anticancer and lipid-modifying therapies, and its promise as source of a novel agent for wound healing and resistance to antibiotic tolerance. The earthworm enzyme lumbrokinase embodies highly effective anticoagulant and thrombolytic properties and has the advantage of not causing bleeding phenomena due to hyperfibrinolysis. Its antifibrotic properties can reduce the excessive accumulation of extracellular matrix. The glycolipoprotein extract G-90 can effectively scavenge reactive oxygen groups and protect cellular tissues from oxidative damage. Earthworms have evolved a well-developed defense mechanism to fight against microbial infections, and the bioactive agents in EE have shown good antibacterial, fungal, and viral properties in in vitro and in vivo experiments and can alleviate inflammatory responses caused by infections, effectively reducing pain. Recent studies have also highlighted the role of EE in lowering blood glucose. EE shows high medicinal value and is expected to be a source of many bioactive compounds.
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In our previous study, yeast-derived peptide Tyr-Pro-Leu-Pro (YPLP) was found to prolong treadmill time and relieve muscle fatigue in ICR mice. The present study aimed to further investigate the antifatigue mechanism of YPLP. Three doses of YPLP (10, 25, and 50 mg/kg·d) were given to exercise mice for 4 weeks. Results showed that YPLP reduced the oxidative response via the nuclear factor erythroid-2-related factor 2 (Nrf2) pathway and promoted energy metabolism through the AMP-activated protein kinase (AMPK) pathway. Label-free proteomics results showed that 81 differential abundance proteins (DAPs) were regulated by high-dose YPLP. These DAPs belonged to proteasome, mitochondrial, and muscle proteins. YPLP was mainly involved in proteasome, aminoacyl-tRNA biosynthesis, focal adhesion, and MAPK signal pathways to enhance muscle endurance. Furthermore, real-time quantitative PCR and Western blotting results proved that YPLP upregulated Psmd14 expression and downregulated p38 MAPK expression. Overall, this study revealed the mechanism behind YPLP to alleviate exercise fatigue.
Asunto(s)
Dipéptidos , Complejo de la Endopetidasa Proteasomal , Proteómica , Animales , Ratones , Complejo de la Endopetidasa Proteasomal/genética , Ratones Endogámicos ICR , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismoRESUMEN
Liver's distinctive function renders it highly susceptible to diverse damage sources. Characterizing the metabolic profiles and spatial signatures in different liver injuries is imperative for early diagnosis and etiology-oriented treatment. In this comparative study, we conducted whole-body spatial metabolomics on zebrafish with liver injury induced by ethanol (EtOH), acetaminophen (APAP), and thioacetamide (TAA). The two specific levels, the whole-body and liver-specific metabolic profiles, as well as their regional distributions, were systematically mapped in situ by mass spectrometry imaging, which is distinct from conventional LC-MS and GC-MS methods. We found that liver injury regions exhibited more pronounced metabolic reprogramming than the entire organism, leading to significant alterations in eight fatty acids, three phospholipids, and four low-molecular-weight metabolites. More importantly, fatty acids as well as small molecule metabolites including glutamine, glutamate, taurine and malic acid displayed contrasting changes between alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD). In addition, phospholipids, including Lyso PC (16:0) and Lyso PE (18:0), demonstrated notable down-regulation in all damaged liver, whereas PC (34:1) underwent upregulation. This study not only deepens insights into distinct potential biomarkers for liver injuries, but also underscores spatial metabolomics as a powerful tool to elucidate possible pathogenic mechanisms in other metabolic diseases.