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1.
J Virol ; 98(5): e0157323, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38572974

RESUMEN

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and characterized by dysregulated immune response. Studies have shown that the SARS-CoV-2 accessory protein ORF7b induces host cell apoptosis through the tumor necrosis factor alpha (TNF-α) pathway and blocks the production of interferon beta (IFN-ß). The underlying mechanism remains to be investigated. In this study, we found that ORF7b facilitated viral infection and production, and inhibited the RIG-I-like receptor (RLR) signaling pathway through selectively interacting with mitochondrial antiviral-signaling protein (MAVS). MAVS439-466 region and MAVS Lys461 were essential for the physical association between MAVS and ORF7b, and the inhibition of the RLR signaling pathway by ORF7b. MAVSK461/K63 ubiquitination was essential for the RLR signaling regulated by the MAVS-ORF7b complex. ORF7b interfered with the recruitment of tumor necrosis factor receptor-related factor 6 (TRAF6) and the activation of the RLR signaling pathway by MAVS. Furthermore, interfering peptides targeting the ORF7b complex reversed the ORF7b-suppressed MAVS-RLR signaling pathway. The most potent interfering peptide V disrupts the formation of ORF7b tetramers, reverses the levels of the ORF7b-inhibited physical association between MAVS and TRAF6, leading to the suppression of viral growth and infection. Overall, this study provides a mechanism for the suppression of innate immunity by SARS-CoV-2 infection and the mechanism-based approach via interfering peptides to potentially prevent SARS-CoV-2 infection.IMPORTANCEThe pandemic coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and continues to be a threat to public health. It is imperative to understand the biology of SARS-CoV-2 infection and find approaches to prevent SARS-CoV-2 infection and ameliorate COVID-19. Multiple SARS-CoV-2 proteins are known to function on the innate immune response, but the underlying mechanism remains unknown. This study shows that ORF7b inhibits the RIG-I-like receptor (RLR) signaling pathway through the physical association between ORF7b and mitochondrial antiviral-signaling protein (MAVS), impairing the K63-linked MAVS polyubiquitination and its recruitment of tumor necrosis factor receptor-related factor 6 (TRAF6) to MAVS. The most potent interfering peptide V targeting the ORF7b-MAVS complex may reverse the suppression of the MAVS-mediated RLR signaling pathway by ORF7b and prevent viral infection and production. This study may provide new insights into the pathogenic mechanism of SARS-CoV-2 and a strategy to develop new drugs to prevent SARS-CoV-2 infection.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , COVID-19 , SARS-CoV-2 , Transducción de Señal , Animales , Humanos , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Apoptosis , COVID-19/virología , COVID-19/inmunología , COVID-19/metabolismo , Proteína 58 DEAD Box/metabolismo , Células HEK293 , Inmunidad Innata , Interferón beta/metabolismo , Receptores Inmunológicos/metabolismo , SARS-CoV-2/inmunología , SARS-CoV-2/metabolismo , Factor 6 Asociado a Receptor de TNF/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Ubiquitinación , Proteínas Reguladoras y Accesorias Virales/metabolismo , Proteínas Reguladoras y Accesorias Virales/genética
2.
J Cell Physiol ; 239(2): e31170, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38149721

RESUMEN

Osteoarthritis (OA) is one of the most prevalent joint diseases in aged people and characterized by articular cartilage degeneration, synovial inflammation, and abnormal bone remodeling. Recent advances in OA research have clearly shown that OA development is associated with aberrant DNA methylation status of many OA-related genes. As one of most important cartilage degrading proteases in OA, a disintegrin and metalloproteinase with thrombospondin motifs subtype 5 (ADAMTS-5) is activated to mediate cartilage degradation in human OA and experimental murine OA models. The pathological factors and signaling pathways mediating ADAMTS-5 activation during OA development are not well defined and have been a focus of intense research. ADAMTS-5 promoter is featured by CpG islands. So far there have been no reports concerning the DNA methylation status in ADAMTS-5 promoter during OA development. In this study, we sought to investigate DNA methylation status in ADAMTS-5 promoter, the role of DNA methylation in ADAMTS-5 activation in OA, and the underlying mechanisms. The potential for anti-OA intervention therapy which is based on modulating DNA methylation is also explored. Our results showed that DNA methyltransferases 1 (Dnmt1) downregulation-associated ADAMTS-5 promoter demethylation played an important role in ADAMTS-5 activation in OA, which facilitated SPI-1 binding on ADAMTS-5 promoter to activate ADAMTS-5 expression. More importantly, OA pathological phenotype of mice was alleviated in response to Dnmt1-induced DNA methylation of ADAMTS-5 promoter. Our study will benefit not only for deeper insights into the functional role and regulation mechanisms of ADAMTS-5 in OA, but also for the discovery of disease-modifying OA drugs on the basis of ADAMTS-5 via modulating DNA methylation status.


Asunto(s)
Cartílago Articular , Péptidos y Proteínas de Señalización Intercelular , Osteoartritis , Anciano , Animales , Humanos , Masculino , Ratones , Cartílago Articular/metabolismo , Condrocitos/metabolismo , Desmetilación del ADN , Células HEK293 , Ratones Endogámicos C57BL , Osteoartritis/patología , Regiones Promotoras Genéticas/genética
3.
Opt Lett ; 49(3): 678-681, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300088

RESUMEN

Characterizing laser frequency noise is essential for applications including optical sensing and coherent optical communications. Accurate measurement of ultra-narrow linewidth lasers over a wide frequency range using existing methods is still challenging. Here we present a method for characterizing the frequency noise of lasers using a high-finesse plano-concave optical microresonator (PCMR) acting as a frequency discriminator. To enable noise measurements at a wide range of laser frequencies, an array of PCMRs was produced with slight variations of thickness resulting in a series of discriminators operating at a series of periodical frequencies. This method enables measuring the frequency noise over a wide linewidth range (15 Hz to <100 MHz) over the 1440-1630 nm wavelength range. To assess the performance of the method, four different lasers were characterized, and the results were compared to the estimations of a commercial frequency noise analyzer.

4.
Int J Mol Sci ; 25(14)2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39063070

RESUMEN

Plastid retrograde signaling plays a key role in coordinating the expression of plastid genes and photosynthesis-associated nuclear genes (PhANGs). Although plastid retrograde signaling can be substantially compromised by mitochondrial dysfunction, it is not yet clear whether specific mitochondrial factors are required to regulate plastid retrograde signaling. Here, we show that mitochondrial ATP synthase beta-subunit mutants with decreased ATP synthase activity are impaired in plastid retrograde signaling in Arabidopsis thaliana. Transcriptome analysis revealed that the expression levels of PhANGs were significantly higher in the mutants affected in the AT5G08670 gene encoding the mitochondrial ATP synthase beta-subunit, compared to wild-type (WT) seedlings when treated with lincomycin (LIN) or norflurazon (NF). Further studies indicated that the expression of nuclear genes involved in chloroplast and mitochondrial retrograde signaling was affected in the AT5G08670 mutant seedlings treated with LIN. These changes might be linked to the modulation of some transcription factors (TFs), such as LHY (Late Elongated Hypocotyl), PIF (Phytochrome-Interacting Factors), MYB, WRKY, and AP2/ERF (Ethylene Responsive Factors). These findings suggest that the activity of mitochondrial ATP synthase significantly influences plastid retrograde signaling.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Regulación de la Expresión Génica de las Plantas , ATPasas de Translocación de Protón Mitocondriales , Plastidios , Transducción de Señal , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , ATPasas de Translocación de Protón Mitocondriales/metabolismo , ATPasas de Translocación de Protón Mitocondriales/genética , Plastidios/metabolismo , Plastidios/genética , Mitocondrias/metabolismo , Plantones/genética , Plantones/metabolismo , Mutación , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Lincomicina/farmacología , Perfilación de la Expresión Génica
5.
Int J Mol Sci ; 25(5)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38473801

RESUMEN

Epidermal cells are the main avenue for signal and material exchange between plants and the environment. Leaf epidermal cells primarily include pavement cells, guard cells, and trichome cells. The development and distribution of different epidermal cells are tightly regulated by a complex transcriptional regulatory network mediated by phytohormones, including jasmonic acid, and transcription factors. How the fate of leaf epidermal cells is determined, however, is still largely unknown due to the diversity of cell types and the complexity of their regulation. Here, we characterized the transcriptional profiles of epidermal cells in 3-day-old true leaves of Arabidopsis thaliana using single-cell RNA sequencing. We identified two genes encoding BASIC LEUCINE-ZIPPER (bZIP) transcription factors, namely bZIP25 and bZIP53, which are highly expressed in pavement cells and early-stage meristemoid cells. Densities of pavement cells and trichome cells were found to increase and decrease, respectively, in bzip25 and bzip53 mutants, compared with wild-type plants. This trend was more pronounced in the presence of jasmonic acid, suggesting that these transcription factors regulate the development of trichome cells and pavement cells in response to jasmonic acid.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Ciclopentanos , Oxilipinas , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico , Células Epidérmicas , Factores de Transcripción , Hojas de la Planta , Tricomas , Análisis de Secuencia de ARN , Regulación de la Expresión Génica de las Plantas
6.
BMC Nurs ; 23(1): 255, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38649929

RESUMEN

BACKGROUND: Poor nurse-patient relationship poses an obstacle to care delivery, jeopardizing patient experience and patient care outcomes. Measuring nurse-patient relationship is challenging given its multi-dimensional nature and a lack of well-established scales. PURPOSE: This study aimed to develop a multi-dimensional scale measuring nurse-patient relationship in China. METHODS: A preliminary scale was constructed based on the existing literature and Delphi consultations with 12 nursing experts. The face validity of the scale was tested through a survey of 45 clinical nurses. This was followed by a validation study on 620 clinical nurses. Cronbach's α, content validity and known-group validity of the scale were assessed. The study sample was further divided into two for Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA), respectively, to assess the construct validity of the scale. RESULTS: The Nurse-Patient Relationship Scale (NPRS) containing 23 items was developed and validated, measuring five dimensions: nursing behavior, nurse understanding and respect for patient, patient misunderstanding and mistrust in nurse, communication with patient, and interaction with patient. The Cronbach's α of the NPRS ranged from 0.725 to 0.932, indicating high internal consistency. The CFA showed excellent fitness of data into the five-factor structure: χ2/df = 2.431, GFI = 0.933, TLI = 0.923, CFI = 0.939, IFI = 0.923, RMSEA = 0.070. Good content and construct validity are demonstrated through expert consensus and psychometric tests. CONCLUSION: The NPRS is a valid tool measuring nurse-patient relationship in China.

7.
BMC Oral Health ; 24(1): 754, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38951770

RESUMEN

OBJECTIVES: This study investigated the effectiveness of a deep convolutional neural network (CNN) in diagnosing and staging caries lesions in quantitative light-induced fluorescence (QLF) images taken by a self-manufactured handheld device. METHODS: A small toothbrush-like device consisting of a 400 nm UV light-emitting lamp with a 470 nm filter was manufactured for intraoral imaging. A total of 133 cases with 9,478 QLF images of teeth were included for caries lesion evaluation using a CNN model. The database was divided into development, validation, and testing cohorts at a 7:2:1 ratio. The accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUC) were calculated for model performance. RESULTS: The overall caries prevalence was 19.59%. The CNN model achieved an AUC of 0.88, an accuracy of 0.88, a specificity of 0.94, and a sensitivity of 0.64 in the validation cohort. They achieved an overall accuracy of 0.92, a sensitivity of 0.95 and a specificity of 0.55 in the testing cohort. The model can distinguish different stages of caries well, with the best performance in detecting deep caries followed by intermediate and superficial lesions. CONCLUSIONS: Caries lesions have typical characteristics in QLF images and can be detected by CNNs. A QLF-based device with CNNs can assist in caries screening in the clinic or at home. TRIAL REGISTRATION: The clinical trial was registered in the Chinese Clinical Trial Registry (No. ChiCTR2300073487, Date: 12/07/2023).


Asunto(s)
Caries Dental , Redes Neurales de la Computación , Fluorescencia Cuantitativa Inducida por la Luz , Humanos , Caries Dental/diagnóstico , Caries Dental/diagnóstico por imagen , Femenino , Fluorescencia Cuantitativa Inducida por la Luz/instrumentación , Masculino , Adulto , Sensibilidad y Especificidad , Persona de Mediana Edad , Adolescente , Adulto Joven , Curva ROC
8.
Int Nurs Rev ; 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38191960

RESUMEN

AIM: This study tested the mediating role of the nurse-patient relationship and self-rated health in the effect of emotional labour on turnover intention among nurses in China. BACKGROUND: The underlying mechanism behind the effect of emotional labour on turnover intention remains inadequately understood. INTRODUCTION: Nurses with a high level of emotional labour are predisposed to experiencing poor health and tension in their relationships with patients, which may increase turnover intention. METHODS: A cross-sectional survey of 527 nurses in a public tertiary hospital in Qiqihar, located in China's Heilongjiang province, was conducted. Emotional labour and turnover intention were assessed using existing validated scales containing multiple items, while the nurse-patient relationship and self-rated health were assessed using single items, respectively. Baron and Kenny's causal steps and the Karlson/Holm/Breen method were adopted to test the mediating effects of the nurse-patient relationship and self-rated health in the association between emotional labour and turnover intention after adjusting for variations in sociodemographic and job characteristics. RESULTS: Emotional labour was positively associated with turnover intention. Self-rated poor health and a disharmonious nurse-patient relationship partially mediated the positive effect of emotional labour on turnover intention. CONCLUSIONS: Emotional labour significantly affects the turnover intention of nurses working in public tertiary hospitals in China, and this effect is partially mediated by self-rated health and the nurse-patient relationship. IMPLICATIONS FOR NURSING PRACTICE AND NURSING POLICY: Giving more attention to nurses' negative emotions and work attitudes is crucial. Developing comprehensive strategies for enhancing nurses' emotional management ability, promoting their physical and psychological well-being, and improving nurse-patient relationship to reduce nurses' turnover.

9.
Mikrochim Acta ; 191(1): 60, 2023 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-38153646

RESUMEN

A new fluorescence sensing strategy has been developed. Four bimetallic nanoclusters, gold/silver, gold/copper, gold/molybdenum and gold/cobalt, were prepared using bovine serum albumin (BSA) as a reducing and stabilizing agent. The fluorescence properties of four nanoclusters were explored by solid-state UV and XPS. The gold/silver nanoclusters (BSA-Au/Ag NCs) with the best ratiometric fluorescence properties for gallic acid (GA) in plants were selected to realize the sensitive detection of GA. GA affected the conformation of BSA, thereby disrupting the luminescent environment of the nanoclusters, resulting in a pronounced fluorescence quenching at 566 nm. The ratiometric fluorescence signal (I566/I453) was used for trace detection of GA in plants. It has a wide response range of 1.25-40.0 µM and a low detection limit of 45.27 nM. GA was detected at 19.49 µM in the plant extract, and the spiked recoveries ranged from 96.09 to 104.6%. In addition, due to the non-toxic and biocompatible properties of BSA, BSA-Au/Ag NCs have also been validated for fluorescence imaging of plant tissues. It realized the comparison of GA content in different parts of plants and the difference of GA content in plants after abiotic stress. Therefore, the developed strategy offers potential application for the analytical study of active substances in plants.


Asunto(s)
Ácido Gálico , Oro , Nanopartículas del Metal , Plantas , Plata , Ácido Gálico/análisis , Imagen Óptica , Albúmina Sérica Bovina , Plantas/química
10.
Sci Rep ; 14(1): 14614, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918598

RESUMEN

Among various non-contact direct ink writing techniques, aerosol jet printing (AJP) stands out due to its distinct advantages, including a more adaptable working distance (2-5 mm) and higher resolution (~ 10 µm). These characteristics make AJP a promising technology for the precise customization of intricate electrical functional devices. However, complex interactions among the machine, process, and materials result in low controllability over the electrical performance of printed lines. This significantly affects the functionality of printed components, thereby limiting the broad applications of AJP. Therefore, a systematic machine learning approach that integrates experimental design, geometrical features extraction, and non-parametric modeling is proposed to achieve printing quality optimization and electrical resistivity prediction for the printed lines in AJP. Specifically, three classical convolutional neural networks (CNNs) architectures are compared for extracting representative features of printed lines, and an optimal operating window is identified to effectively discriminate better line morphology from inferior printed line patterns within the design space. Subsequently, three representative non-parametric machine learning techniques are employed for resistivity modeling. Following that, the modeling performances of the adopted machine learning methods were systematically compared based on four conventional evaluation metrics. Together, these aspects contribute to optimizing the printed line morphology, while simultaneously identifying the optimal resistivity model for accurate predictions in AJP.

11.
Medicine (Baltimore) ; 103(31): e39153, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39093744

RESUMEN

BACKGROUND: WD repeat domain 43 (WDR43) is a protein component that encodes WD-repeats and is involved in ribosome biogenesis. However, little is known about the role of WDR43 in cancer prognosis and immune modulation. METHODS: In this study, we analyzed the expression and prognostic significance of WDR43 in pan-cancer using the Cancer Genome Atlas, the Genotype-Tissue Expression, and the Human Protein Atlas. We also examined the differential expression of WDR43 in liver hepatocellular carcinoma (LIHC) and adjacent tissues of 48 patients using immunohistochemistry. Additionally, we investigated the correlation between WDR43 and clinical characteristics, gene alterations, tumor mutation burden, microsatellite instability, mismatch repair, tumor microenvironment, immune infiltrating cells, and immune-related genes using bioinformatics methods. Gene set enrichment analysis was conducted, and potential biological mechanisms were identified. RESULTS: Immunohistochemistry staining showed that WDR43 was overexpressed in LIHC among 48 patients. Upregulation of WDR43 was associated with unfavorable prognosis, including overall survival in various types of cancer such as LIHC, uterine corpus endometrial cancer, head and neck squamous cell carcinoma, and pancreatic adenocarcinoma. Differential expression of WDR43 was significantly correlated with microsatellite instability, mismatch repair, and immune cell infiltration. Gene ontology annotation analysis revealed that these genes were significantly enriched in immune-related functions, including immune response, immune regulation, and signaling pathways. CONCLUSION: We conducted a thorough investigation of the clinical features, phases of tumor development, immune infiltration, gene mutation, and functional enrichment analysis of WDR43 in various types of cancer. This research offers valuable insight into the significance and function of WDR43 in clinical therapy.


Asunto(s)
Biomarcadores de Tumor , Humanos , Pronóstico , Femenino , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Masculino , Inestabilidad de Microsatélites , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/mortalidad , Microambiente Tumoral/inmunología , Microambiente Tumoral/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/mortalidad , Persona de Mediana Edad , Inmunohistoquímica , Neoplasias/inmunología , Neoplasias/genética , Neoplasias/patología , Regulación Neoplásica de la Expresión Génica , Linfocitos Infiltrantes de Tumor/inmunología
12.
Sci Total Environ ; 912: 169356, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38110091

RESUMEN

As the pursuit of "carbon neutrality" gains momentum, the emphasis on low-carbon solutions, emphasizing energy conservation and resource reuse, has introduced fresh challenges to conventional wastewater treatment approaches. Precisely evaluating carbon emissions in urban water supply and drainage systems, wastewater treatment plants, and establishing carbon-neutral operating models has become a pivotal concern in the future of wastewater treatment. Regrettably, limited research has been devoted to carbon accounting and the development of carbon-neutral strategies for wastewater treatment. In this review, to facilitate comprehensive carbon accounting, we initially recognizes direct and indirect carbon emission sources in the wastewater treatment process. We then provide an overview of several major carbon accounting methods and propose a carbon accounting framework. Furthermore, we advocate for a systemic perspective, highlighting that achieving carbon neutrality in wastewater treatment extends beyond the boundaries of wastewater treatment plants. We assess current technical measures both within and outside the plants that contribute to achieving carbon-neutral operations. Encouraging the application of intelligent algorithms for the multifaceted monitoring and control of wastewater treatment processes is paramount. Supporting resource and energy recycling is also essential, as is recognizing the benefits of synergistic wastewater treatment technologies. We advocate a systematic, multi-level planning approach that takes into account a wide range of factors. Our goal is to offer valuable insights and support for the practical implementation of water environment management within the framework of carbon neutrality, and to advance sustainable socio-economic development and contribute to a more environmentally responsible future.

13.
Sci Rep ; 14(1): 15766, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982175

RESUMEN

Mining stress induces deformation and fracture of the overlaying rock, which will result in water filling the separation layer if the aquifer finds access to abscission space along the fracture channels. Accurate detection is crucial to prevent water hazards induced by water-bearing fractures. The 3-D time-domain finite-difference method with Yee's grid was adopted to calculate full-space transient electromagnetic response; meanwhile, a typical geologic and geophysical model with a water-bearing block in an separation layer was built according to regional tectonics and stratigraphic developments. By using numerical simulation, the induced voltage and apparent resistivity for both vertical and horizontal components were acquired, and then an approximate inversion was carried out based on the "smoke ring" theory. The results indicate that the diffusion velocity of induced voltage is significantly affected by the water-bearing body in the fracture, and the horizontal velocity of induced voltage is lower than the vertical one. The induced voltage curves indicate that the horizontal response to an anomaly body is stronger than the vertical one, leading to a high apparent resistivity resolution of conductivity contrast and separation layer boundary in the horizontal direction. The results of 3-D simulation making use of a measured data model also demonstrate that the horizontal component of apparent resistivity can reflect the electrical structure in a better way; however, its ability to recognize the concealed and fine conductor is rather weak. Accordingly, the observation method or numerical interpolation method needs to be further improved for data processing and interpretation.

14.
Polymers (Basel) ; 16(11)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38891397

RESUMEN

An experimental device fixed with a laser displacement sensor was assembled to investigate the rebound behaviors and damping mechanism of rubber balls prepared with ethylene-propylene-diene monomer (EPDM)/chlorinated butyl rubber (CIIR) blends. The result showed that a prediction model was proposed to characterize the damping capacity by using the rebound height of the rubber balls. The lower rebound height corresponded to better damping capacity. A modified equation relating to the rebound height has been obtained from the theoretical derivation on the basis of the dynamic mechanical analysis, showing that the rebound height was affected by the deformation frequency, the external excitation, and the nature of rubber blends. Furthermore, the energy dissipation rate (EDR), defined by the ratio of the height loss to the rebound time, was proposed to further characterize the damping capacity. The EDR value was shown to be highest for the pure CIIR and lowest for the pure EPDM, exhibiting a decreasing trend with the increase in EPDM content in the rubber blends. It can be expected that the damping capacity of the EPDM/CIIR blends decreases with the decrease in external excitation, the conclusion of which plays a key role in the formulation design of viscoelastic damping rubber materials.

15.
Oncol Lett ; 27(2): 60, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38192670

RESUMEN

Cell surface markers are most widely used in the study of cancer stem cells (CSCs). However, cell surface markers that are safely and stably expressed in CSCs have yet to be identified. Colonic CSCs express leukocyte CD14. CD14 binding to the ligand lipopolysaccharide (LPS) is involved in the inflammatory response via the Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88) signaling pathway. TLR4 and MyD88 have been reported to promote the proliferation, metastasis and tumorigenicity of colon cancer cells, which is consistent with the characteristics of CSCs. In the present study, the proposed experimental method to detect cell proliferation, metastasis and tumorigenesis was used to confirm that, under LPS stimulation, CD14 promoted the proliferation, migration and tumorigenesis of colonic CSCs via the TLR4/MyD88 signaling pathway. Cell Counting Kit-8 and 5-ethynyl-2'-deoxyuridine assays were used to assess the proliferation and migration of the cells. Colony formation and nude mouse xenograft assays were used to assess the capacity of cells to form tumors. Using western blotting and reverse transcription-quantitative PCR, the mRNA and protein levels of CD14, TLR4 and MyD88 were examined. It was confirmed that CD14 promoted the proliferation, metastasis and tumorigenesis of colon CSCs in response to LPS stimulation via the TLR4/MyD88 signaling pathway, and CD14+ colon cancer cells were successfully isolated and sorted. According to the results of proliferation assay, it was determined that CD14 regulated the LPS-induced proliferation of colon CSCs. CD14, TLR4 and MyD88 protein and mRNA expression was upregulated in colon CSCs in response to LPS stimulation. This indicates a potential novel target for colon CSC-related studies.

16.
Int Immunopharmacol ; 140: 112831, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39111149

RESUMEN

Chronic hepatitis B virus (HBV) infection continues to be a prominent cause of liver fibrosis and end-stage liver disease in China, necessitating the development of effective therapeutic strategies. This study investigated the potential of targeting TGR5 to alleviate liver fibrosis by impeding the activation of hepatic stellate cells (HSCs), which play a pivotal role in fibrotic progression. Using the human hepatic stellate cell line LX-2 overexpressing hepatitis B virus X protein (HBX), this study revealed that TGR5 activation through INT-777 inhibits HBX-induced LX-2 cell activation, thereby ameliorating liver fibrosis, which is associated with the attenuation of mitochondrial fission and introduces a novel regulatory pathway in liver fibrosis. Additional experiments with mitochondrial fission inducers and inhibitors confirm the crucial role of mitochondrial dynamics in TGR5-mediated effects. In vivo studies using TGR5 knockout mice substantiate these findings, demonstrating exacerbated fibrosis in the absence of TGR5 and its alleviation with the mitochondrial fission inhibitor Mdivi-1. Overall, this study provides insights into TGR5-mediated regulation of liver fibrosis through the modulation of mitochondrial fission in HSCs, suggesting potential therapeutic strategies for liver fibrosis intervention.

17.
Microbiol Spectr ; 12(4): e0341023, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38376366

RESUMEN

The nucleocapsid protein of SARS-CoV-2 plays significant roles in viral assembly, immune evasion, and viral stability. Due to its immunogenicity, high expression levels during COVID-19, and conservation across viral strains, it represents an attractive target for antiviral treatment. In this study, we identified and characterized a single-stranded DNA aptamer, N-Apt17, which effectively disrupts the liquid-liquid phase separation (LLPS) mediated by the N protein. To enhance the aptamer's stability, a circular bivalent form, cb-N-Apt17, was designed and evaluated. Our findings demonstrated that cb-N-Apt17 exhibited improved stability, enhanced binding affinity, and superior inhibition of N protein LLPS; thus, it has the potential inhibition ability on viral replication. These results provide valuable evidence supporting the potential of cb-N-Apt17 as a promising candidate for the development of antiviral therapies against COVID-19.IMPORTANCEVariants of SARS-CoV-2 pose a significant challenge to currently available COVID-19 vaccines and therapies due to the rapid epitope changes observed in the viral spike protein. However, the nucleocapsid (N) protein of SARS-CoV-2, a highly conserved structural protein, offers promising potential as a target for inhibiting viral replication. The N protein forms complexes with genomic RNA, interacts with other viral structural proteins during virion assembly, and plays a critical role in evading host innate immunity by impairing interferon production during viral infection. In this investigation, we discovered a single-stranded DNA aptamer, designated as N-Apt17, exhibiting remarkable affinity and specificity for the N protein. Notably, N-Apt17 disrupts the liquid-liquid phase separation (LLPS) of the N protein. To enhance the stability and molecular recognition capabilities of N-Apt17, we designed a circular bivalent DNA aptamer termed cb-N-Apt17. In both in vivo and in vitro experiments, cb-N-Apt17 exhibited increased stability, enhanced binding affinity, and superior LLPS disrupting ability. Thus, our study provides essential proof-of-principle evidence supporting the further development of cb-N-Apt17 as a therapeutic candidate for COVID-19.


Asunto(s)
COVID-19 , Proteínas de la Nucleocápside , Humanos , SARS-CoV-2/genética , ADN de Cadena Simple/farmacología , Vacunas contra la COVID-19 , Antivirales/farmacología
18.
Biosens Bioelectron ; 248: 115998, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38176254

RESUMEN

The release of isoprene by plants is considered to be an adaptation to the environment. Herein, a highly selective coumarin fluorescent probe (DMIC) was designed for detecting isoprene. When isoprene came into contact with the maleimide of DMIC, an electrophilic addition process took place. The powerful push-pull effect of DMIC was disrupted. Simultaneously, intramolecular charge transfer was initiated. This enabled DMIC to achieve rapid detection of isoprene within 5 min. Furthermore, excellent linearity was observed in the concentration range of 1-560 ppm (R2 = 0.996). A limit of detection is 1.6 ppm. DMIC was applied to in vitro studies of plant release of liberated isoprene. By monitoring the release of isoprene from different tree species throughout the day, the dynamics of isoprene release from plants throughout the day have been successfully revealed. In addition, the release of isoprene varied considerably among different tree species. In particular, the biocompatibility of DMIC allowed for the in vivo detection of isoprene using fluorescence imaging. The results successfully revealed the dynamics of isoprene release in plants under stress. The amount of isoprene that a plant produced increased with the severity of the stress it experienced. This suggested that the level of isoprene content in plants could be used as a preliminary indicator of the physiological health status of plants. This research demonstrates great potential for clarifying signal transduction in biological systems. It provided ideas for further understanding the biology of isoprene.


Asunto(s)
Técnicas Biosensibles , Butadienos , Plantas , Hemiterpenos , Cumarinas
19.
Front Cell Infect Microbiol ; 14: 1415885, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38846351

RESUMEN

Corona Virus Disease 2019 (COVID-19) is a highly prevalent and potent infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Until now, the world is still endeavoring to develop new ways to diagnose and treat COVID-19. At present, the clinical prevention and treatment of COVID-19 mainly targets the spike protein on the surface of SRAS-CoV-2. However, with the continuous emergence of SARS-CoV-2 Variants of concern (VOC), targeting the spike protein therapy shows a high degree of limitation. The Nucleocapsid Protein (N protein) of SARS-CoV-2 is highly conserved in virus evolution and is involved in the key process of viral infection and assembly. It is the most expressed viral structural protein after SARS-CoV-2 infection in humans and has high immunogenicity. Therefore, N protein as the key factor of virus infection and replication in basic research and clinical application has great potential research value. This article reviews the research progress on the structure and biological function of SARS-CoV-2 N protein, the diagnosis and drug research of targeting N protein, in order to promote researchers' further understanding of SARS-CoV-2 N protein, and lay a theoretical foundation for the possible outbreak of new and sudden coronavirus infectious diseases in the future.


Asunto(s)
COVID-19 , Proteínas de la Nucleocápside de Coronavirus , Fosfoproteínas , SARS-CoV-2 , SARS-CoV-2/genética , Humanos , Proteínas de la Nucleocápside de Coronavirus/genética , Proteínas de la Nucleocápside de Coronavirus/química , Proteínas de la Nucleocápside de Coronavirus/metabolismo , COVID-19/virología , COVID-19/diagnóstico , Fosfoproteínas/metabolismo , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo , Glicoproteína de la Espiga del Coronavirus/química , Proteínas de la Nucleocápside/metabolismo , Proteínas de la Nucleocápside/genética
20.
Sci Rep ; 14(1): 2074, 2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38267565

RESUMEN

We explored the effect of 3 mg/kg of caffeine supplementation on the cognitive ability and shooting performance of elite e-sports players. Nine e-sports players who had received professional training in e-sports and had won at least eighth place in national-level e-sports shooting competitions. After performing three to five familiarization tests, we employed a single blind, randomized crossover design to divide participants into caffeine trial (CAF) and placebo trial (PL). The CAF trial took capsules with 3 mg/kg of caffeine, whereas the PL trial took a placebo capsule. After a one-hour rest, the Stroop task, the visual search ability test, and the shooting ability test were conducted. The CAF trial's performance in the Stroop task in terms of congruent condition (P = 0.023) and visual search reaction time with 20 items (P = 0.004) was significantly superior to those of the PL trial. In the shooting test, the CAF trial's kill ratio (P = 0.020) and hit accuracy (P = 0.008) were significantly higher, and the average time to target (P = 0.001) was significantly shorter than those of the PL trial. Caffeine supplementation significantly improves e-sports players' reaction times and shooting performance.


Asunto(s)
Cafeína , Cognición , Humanos , Estudios Cruzados , Cafeína/farmacología , Método Simple Ciego , Suplementos Dietéticos
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