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1.
Cell ; 175(1): 40-42, 2018 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-30241614

RESUMEN

Although there is much focus on the impact of mutations on structured protein domains, less is known about their impact on unstructured regions. In this issue, Meyer et al. demonstrate that mutations resulting in the emergence of new short linear peptide motifs within intrinsically disordered protein regions can cause human genetic diseases by gain of function.


Asunto(s)
Mutación con Ganancia de Función , Péptidos , Humanos , Mutación
2.
Genes Dev ; 35(21-22): 1510-1526, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34593603

RESUMEN

Cleavage and polyadenylation factor (CPF/CPSF) is a multiprotein complex essential for mRNA 3' end processing in eukaryotes. It contains an endonuclease that cleaves pre-mRNAs, and a polymerase that adds a poly(A) tail onto the cleaved 3' end. Several CPF subunits, including Fip1, contain intrinsically disordered regions (IDRs). IDRs within multiprotein complexes can be flexible, or can become ordered upon interaction with binding partners. Here, we show that yeast Fip1 anchors the poly(A) polymerase Pap1 onto CPF via an interaction with zinc finger 4 of another CPF subunit, Yth1. We also reconstitute a fully recombinant 850-kDa CPF. By incorporating selectively labeled Fip1 into recombinant CPF, we could study the dynamics of Fip1 within the megadalton complex using nuclear magnetic resonance (NMR) spectroscopy. This reveals that a Fip1 IDR that connects the Yth1- and Pap1-binding sites remains highly dynamic within CPF. Together, our data suggest that Fip1 dynamics within the 3' end processing machinery are required to coordinate cleavage and polyadenylation.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Poliadenilación , Precursores del ARN/metabolismo , ARN Mensajero/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Factores de Escisión y Poliadenilación de ARNm/genética , Factores de Escisión y Poliadenilación de ARNm/metabolismo
3.
PLoS Pathog ; 20(3): e1012130, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38551978

RESUMEN

Classical Swine Fever (CSF), caused by the Classical Swine Fever Virus (CSFV), inflicts significant economic losses on the global pig industry. A key factor in the challenge of eradicating this virus is its ability to evade the host's innate immune response, leading to persistent infections. In our study, we elucidate the molecular mechanism through which CSFV exploits m6A modifications to circumvent host immune surveillance, thus facilitating its proliferation. We initially discovered that m6A modifications were elevated both in vivo and in vitro upon CSFV infection, particularly noting an increase in the expression of the methyltransferase METTL14. CSFV non-structural protein 5B was found to hijack HRD1, the E3 ubiquitin ligase for METTL14, preventing METTL14 degradation. MeRIP-seq analysis further revealed that METTL14 specifically targeted and methylated TLRs, notably TLR4. METTL14-mediated regulation of TLR4 degradation, facilitated by YTHDF2, led to the accelerated mRNA decay of TLR4. Consequently, TLR4-mediated NF-κB signaling, a crucial component of the innate immune response, is suppressed by CSFV. Collectively, these data effectively highlight the viral evasion tactics, shedding light on potential antiviral strategies targeting METTL14 to curb CSFV infection.


Asunto(s)
Adenina , Virus de la Fiebre Porcina Clásica , Peste Porcina Clásica , Animales , Virus de la Fiebre Porcina Clásica/genética , Inmunidad Innata , Porcinos , Receptor Toll-Like 4
4.
J Virol ; 98(2): e0199423, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38240591

RESUMEN

Following the successful control of poliovirus, the re-emergence of respiratory enterovirus D68 (EV-D68), a prominent non-polio enterovirus, has become a serious public health concern worldwide. Host innate immune responses are the primary defense against EV-D68 invasion; however, the mechanism underlying viral evasion of the antiviral activity of interferons (IFN) remains unclear. In this study, we found that EV-D68 inhibited type I IFN signaling by cleaving signal transducer and activator of transcription 1 (STAT1), a crucial factor in cellular responses to interferons and other cytokines. We observed that the prototype and circulating EV-D68 strains conserved their ability to induce STAT1 cleavage and attenuate IFN signal transduction. Further investigation revealed that EV-D68 3C protease cleaves STAT1 at the 131Q residue. Interestingly, not all enterovirus-encoded 3C proteases exhibited this ability. EV-D68 and poliovirus 3C proteases efficiently induced STAT1 cleavage; whereas, 3C proteases from EV-A71, coxsackievirus A16, and echoviruses did not. STAT1 cleavage also abolished the nuclear translocation capacity of STAT1 in response to IFN stimulation to activate downstream signaling elements. Overall, these results suggest that STAT1, targeted by viral protease 3C, is utilized by EV-D68 to subvert the host's innate immune response.IMPORTANCEEnterovirus D68 (EV-D68) has significantly transformed over the past decade, evolving from a rare pathogen to a potential pandemic pathogen. The interferon (IFN) signaling pathway is an important defense mechanism and therapeutic target for the host to resist viral invasion. Previous studies have reported that the EV-D68 virus blocks or weakens immune recognition and IFN production in host cells through diverse strategies; however, the mechanisms of EV-D68 resistance to IFN signaling have not been fully elucidated. Our study revealed that EV-D68 relies on its own encoded protease, 3C, to directly cleave signal transducer and activator of transcription 1 (STAT1), a pivotal transduction component in the IFN signaling pathway, disrupting the IFN-mediated antiviral response. Previous studies on human enteroviruses have not documented direct cleavage of the STAT1 protein to evade cellular immune defenses. However, not all enteroviral 3C proteins can cleave STAT1. These findings highlight the diverse evolutionary strategies different human enteroviruses employ to evade host immunity.


Asunto(s)
Proteasas Virales 3C , Enterovirus Humano D , Interferón Tipo I , Transducción de Señal , Humanos , Proteasas Virales 3C/metabolismo , Antígenos Virales/metabolismo , Antivirales/farmacología , Cisteína Endopeptidasas/metabolismo , Enterovirus Humano D/fisiología , Interacciones Huésped-Patógeno , Evasión Inmune , Inmunidad Innata , Interferón Tipo I/metabolismo , Péptido Hidrolasas/metabolismo , Proteolisis , Factor de Transcripción STAT1/metabolismo , Proteínas Virales/metabolismo
5.
J Virol ; 98(2): e0190923, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38289118

RESUMEN

Pyroptosis, a pro-inflammatory programmed cell death, has been implicated in the pathogenesis of coronavirus disease 2019 and other viral diseases. Gasdermin family proteins (GSDMs), including GSDMD and GSDME, are key regulators of pyroptotic cell death. However, the mechanisms by which virus infection modulates pyroptosis remain unclear. Here, we employed a mCherry-GSDMD fluorescent reporter assay to screen for viral proteins that impede the localization and function of GSDMD in living cells. Our data indicated that the main protease NSP5 of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) blocked GSDMD-mediated pyroptosis via cleaving residues Q29 and Q193 of GSDMD. While another SARS-CoV-2 protease, NSP3, cleaved GSDME at residue G370 but activated GSDME-mediated pyroptosis. Interestingly, respiratory enterovirus EV-D68-encoded proteases 3C and 2A also exhibit similar differential regulation on the functions of GSDMs by inactivating GSDMD but initiating GSDME-mediated pyroptosis. EV-D68 infection exerted oncolytic effects on human cancer cells by inducing pyroptotic cell death. Our findings provide insights into how respiratory viruses manipulate host cell pyroptosis and suggest potential targets for antiviral therapy as well as cancer treatment.IMPORTANCEPyroptosis plays a crucial role in the pathogenesis of coronavirus disease 2019, and comprehending its function may facilitate the development of novel therapeutic strategies. This study aims to explore how viral-encoded proteases modulate pyroptosis. We investigated the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and respiratory enterovirus D68 (EV-D68) proteases on host cell pyroptosis. We found that SARS-CoV-2-encoded proteases NSP5 and NSP3 inactivate gasdermin D (GSDMD) but initiate gasdermin E (GSDME)-mediated pyroptosis, respectively. We also discovered that another respiratory virus EV-D68 encodes two distinct proteases 2A and 3C that selectively trigger GSDME-mediated pyroptosis while suppressing the function of GSDMD. Based on these findings, we further noted that EV-D68 infection triggers pyroptosis and produces oncolytic effects in human carcinoma cells. Our study provides new insights into the molecular mechanisms underlying virus-modulated pyroptosis and identifies potential targets for the development of antiviral and cancer therapeutics.


Asunto(s)
Endopeptidasas , Enterovirus Humano D , Interacciones Microbiota-Huesped , Virus Oncolíticos , Piroptosis , SARS-CoV-2 , Humanos , Línea Celular Tumoral , COVID-19/metabolismo , COVID-19/terapia , COVID-19/virología , Endopeptidasas/genética , Endopeptidasas/metabolismo , Enterovirus Humano D/enzimología , Enterovirus Humano D/genética , Infecciones por Enterovirus/metabolismo , Infecciones por Enterovirus/virología , Gasderminas/antagonistas & inhibidores , Gasderminas/genética , Gasderminas/metabolismo , Viroterapia Oncolítica , Virus Oncolíticos/enzimología , Virus Oncolíticos/genética , SARS-CoV-2/enzimología , SARS-CoV-2/genética , Proteínas Virales/genética , Proteínas Virales/metabolismo
6.
Brief Bioinform ; 24(6)2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37930031

RESUMEN

Reconstructing the full-length sequence of extrachromosomal circular DNA (eccDNA) from short sequencing reads has proved challenging given the similarity of eccDNAs and their corresponding linear DNAs. Previous sequencing methods were unable to achieve high-throughput detection of full-length eccDNAs. Herein, a novel algorithm was developed, called Full-Length eccDNA Detection (FLED), to reconstruct the sequence of eccDNAs based on the strategy that combined rolling circle amplification and nanopore long-reads sequencing technology. Seven human epithelial and cancer cell line samples were analyzed by FLED and over 5000 full-length eccDNAs were identified per sample. The structures of identified eccDNAs were validated by both Polymerase Chain Reaction (PCR) and Sanger sequencing. Compared to other published nanopore-based eccDNA detectors, FLED exhibited higher sensitivity. In cancer cell lines, the genes overlapped with eccDNA regions were enriched in cancer-related pathways and cis-regulatory elements can be predicted in the upstream or downstream of intact genes on eccDNA molecules, and the expressions of these cancer-related genes were dysregulated in tumor cell lines, indicating the regulatory potency of eccDNAs in biological processes. The proposed method takes advantage of nanopore long reads and enables unbiased reconstruction of full-length eccDNA sequences. FLED is implemented using Python3 which is freely available on GitHub (https://github.com/FuyuLi/FLED).


Asunto(s)
ADN Circular , ADN , Humanos , ADN/genética , Reacción en Cadena de la Polimerasa , Línea Celular
7.
Nano Lett ; 24(18): 5420-5428, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38666707

RESUMEN

Artificial intelligence has surged forward with the advent of generative models, which rely heavily on stochastic computing architectures enhanced by true random number generators with adjustable sampling probabilities. In this study, we develop spin-orbit torque magnetic tunnel junctions (SOT-MTJs), investigating their sigmoid-style switching probability as a function of the driving voltage. This feature proves to be ideally suited for stochastic computing algorithms such as the restricted Boltzmann machines (RBM) prevalent in pretraining processes. We exploit SOT-MTJs as both stochastic samplers and network nodes for RBMs, enabling the implementation of RBM-based neural networks to achieve recognition tasks for both handwritten and spoken digits. Moreover, we further harness the weights derived from the preceding image and speech training processes to facilitate cross-modal learning from speech to image generation. Our results clearly demonstrate that these SOT-MTJs are promising candidates for the development of hardware accelerators tailored for Boltzmann neural networks and other stochastic computing architectures.

8.
Biochem Biophys Res Commun ; 706: 149747, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38479243

RESUMEN

Nobiletin is a natural flavonoid found in citrus fruits with beneficial effects, including anti-inflammatory, anti-cancer and anti-oxidation effects. The aim of this study was to investigate whether nobiletin improves mitochondrial function in porcine oocytes and examine the underlying mechanism. Oocytes enclosed by cumulus cells were cultured in TCM-199 for 44 h with 0.1% dimethyl sulfoxide (control), or supplemented with 5, 10, 25, and 50 µM of nobiletin (Nob5, Nob10, Nob25, and Nob50, respectively). Oocyte maturation rate was significantly enhanced in Nob10 (70.26 ± 0.45%) compared to the other groups (control: 60.12 ± 0.47%; Nob5: 59.44 ± 1.63%; Nob25: 63.15 ± 1.38%; Nob50: 46.57 ± 1.19%). The addition of nobiletin reduced the levels of reactive oxygen species and increased glutathione levels. Moreover, Nob10 promoted mitochondrial biogenesis by upregulating the protein levels of sirtuin 1 (SIRT1) and peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC-1α). This resulted in an increase in the number of active mitochondria, mitochondrial DNA copy number, mitochondrial membrane potential, and ATP production, thereby enhancing mitochondrial function. The protein level of p53 decreased, followed by the phosphorylation of B-cell lymphoma 2, suggesting a reduction in mitochondria-mediated apoptosis in the Nob10 group. Additionally, the release of cytochrome c from the mitochondria was significantly diminished along with a decrease in the protein expression of caspase 3. Thus, nobiletin has a great potential to promote the in vitro maturation of porcine oocytes by suppressing oxidative stress and promoting mitochondrial function through the upregulation of the SIRT1/PGC-1α signaling pathway.


Asunto(s)
Flavonas , Mitocondrias , Sirtuina 1 , Animales , Porcinos , Sirtuina 1/metabolismo , Mitocondrias/metabolismo , Transducción de Señal , Oocitos/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo
9.
BMC Plant Biol ; 24(1): 219, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38532379

RESUMEN

BACKGROUND: Drought is considered the main environmental factor restricting apple production and thus the development of the apple industry. Rootstocks play an important role in enhancing the drought tolerance of apple plants. Studies of the physiology have demonstrated that 'ZC9-3' is a strong drought-resistant rootstock, whereas 'Jizhen-2' is a weak drought-resistant rootstock. However, the metabolites in these two apple rootstock varieties that respond to drought stress have not yet been characterized, and the molecular mechanisms underlying their responses to drought stress remain unclear. RESULTS: In this study, the physiological and molecular mechanisms underlying differences in the drought resistance of 'Jizhen-2' (drought-sensitive) and 'ZC9-3' (drought-resistant) apple rootstocks were explored. Under drought stress, the relative water content of the leaves was maintained at higher levels in 'ZC9-3' than in 'Jizhen-2', and the photosynthetic, antioxidant, and osmoregulatory capacities of 'ZC9-3' were stronger than those of 'Jizhen-2'. Metabolome analysis revealed a total of 95 and 156 differentially accumulated metabolites in 'Jizhen-2' and 'ZC9-3' under drought stress, respectively. The up-regulated metabolites in the two cultivars were mainly amino acids and derivatives. Transcriptome analysis revealed that there were more differentially expressed genes and transcription factors in 'ZC9-3' than in 'Jizhen-2' throughout the drought treatment. Metabolomic and transcriptomic analysis revealed that amino acid biosynthesis pathways play key roles in mediating drought resistance in apple rootstocks. A total of 13 metabolites, including L-α-aminoadipate, L-homoserine, L-threonine, L-isoleucine, L-valine, L-leucine, (2S)-2-isopropylmalate, anthranilate, L-tryptophan, L-phenylalanine, L-tyrosine, L-glutamate, and L-proline, play an important role in the difference in drought resistance between 'ZC9-3' and 'Jizhen-2'. In addition, 13 genes encoding O-acetylserine-(thiol)-lyase, S-adenosylmethionine synthetase, ketol-acid isomeroreductase, dihydroxyacid dehydratase, isopropylmalate isomerase, branched-chain aminotransferase, pyruvate kinase, 3-dehydroquinate dehydratase/shikimate 5-dehydrogenase, N-acetylglutamate-5-P-reductase, and pyrroline-5-carboxylate synthetase positively regulate the response of 'ZC9-3' to drought stress. CONCLUSIONS: This study enhances our understanding of the response of apple rootstocks to drought stress at the physiological, metabolic, and transcriptional levels and provides key insights that will aid the cultivation of drought-resistant apple rootstock cultivars. Especially, it identifies key metabolites and genes underlying the drought resistance of apple rootstocks.


Asunto(s)
Malus , Malus/genética , Sequías , Perfilación de la Expresión Génica , Metabolómica , Metaboloma , Aminoácidos , Estrés Fisiológico , Regulación de la Expresión Génica de las Plantas
10.
Small ; 20(29): e2309863, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38368256

RESUMEN

Research on flexible thermoelectric (TE) materials has typically focused on conducting polymers and conducting polymer-based composites. However, achieving TE properties comparable in magnitude to those exhibited by their inorganic counterparts remains a formidable challenge. This study focuses on the synthesis of silver selenide (Ag2Se) nanomaterials using solvothermal methods and demonstrates a significant enhancement in their TE properties through the synergistic dual doping of sulfur and copper. Flexible TE thin films demonstrating excellent flexibility are successfully fabricated using vacuum filtration and hot-pressing techniques. The resulting thin films also exhibited outstanding TE performance, with a high Seebeck coefficient (S = -138.5 µV K-1) and electrical conductivity (σ = 1.19 × 105 S m-1). The record power factor of 2296.8 µW m-1 K-2 at room temperature is primarily attributed to enhanced carrier transport and interfacial energy filtration effects in the composite material. Capitalizing on these excellent TE properties, the maximum power output of flexible TE devices reached 1.13 µW with a temperature difference of 28.6 K. This study demonstrates the potential of Ag2Se-based TE materials for flexible and efficient energy-harvesting applications.

11.
Metab Eng ; 83: 172-182, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38648878

RESUMEN

Microbial bioengineering is a growing field for producing plant natural products (PNPs) in recent decades, using heterologous metabolic pathways in host cells. Once heterologous metabolic pathways have been introduced into host cells, traditional metabolic engineering techniques are employed to enhance the productivity and yield of PNP biosynthetic routes, as well as to manage competing pathways. The advent of computational biology has marked the beginning of a novel epoch in strain design through in silico methods. These methods utilize genome-scale metabolic models (GEMs) and flux optimization algorithms to facilitate rational design across the entire cellular metabolic network. However, the implementation of in silico strategies can often result in an uneven distribution of metabolic fluxes due to the rigid knocking out of endogenous genes, which can impede cell growth and ultimately impact the accumulation of target products. In this study, we creatively utilized synthetic biology to refine in silico strain design for efficient PNPs production. OptKnock simulation was performed on the GEM of Saccharomyces cerevisiae OA07, an engineered strain for oleanolic acid (OA) bioproduction that has been reported previously. The simulation predicted that the single deletion of fol1, fol2, fol3, abz1, and abz2, or a combined knockout of hfd1, ald2 and ald3 could improve its OA production. Consequently, strains EK1∼EK7 were constructed and cultivated. EK3 (OA07△fol3), EK5 (OA07△abz1), and EK6 (OA07△abz2) had significantly higher OA titers in a batch cultivation compared to the original strain OA07. However, these increases were less pronounced in the fed-batch mode, indicating that gene deletion did not support sustainable OA production. To address this, we designed a negative feedback circuit regulated by malonyl-CoA, a growth-associated intermediate whose synthesis served as a bypass to OA synthesis, at fol3, abz1, abz2, and at acetyl-CoA carboxylase-encoding gene acc1, to dynamically and autonomously regulate the expression of these genes in OA07. The constructed strains R_3A, R_5A and R_6A had significantly higher OA titers than the initial strain and the responding gene-knockout mutants in either batch or fed-batch culture modes. Among them, strain R_3A stand out with the highest OA titer reported to date. Its OA titer doubled that of the initial strain in the flask-level fed-batch cultivation, and achieved at 1.23 ± 0.04 g L-1 in 96 h in the fermenter-level fed-batch mode. This indicated that the integration of optimization algorithm and synthetic biology approaches was efficiently rational for PNP-producing strain design.


Asunto(s)
Ingeniería Metabólica , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Simulación por Computador , Técnicas de Silenciamiento del Gen , Terpenos/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
12.
Reproduction ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39051904

RESUMEN

Among the family of GPCR kinases (GRKs) that regulate receptor phosphorylation and signaling termination, G-protein coupled receptor kinase 2 (GRK2) binds to HSP90 in response to hypoxia or other stresses. In the present study, we investigated the effects of GRK2 knockdown and inhibition on porcine embryonic development from the zygote stage. Immunofluorescence and western blotting were used to determine the localization and expression, respectively, of GRK2 and related proteins. First, GRK2 and p-GRK2 were expressed in both the cytoplasm and membrane and co-localized with HSP90 on the membrane. The mRNA level of GRK2 increased until the 8C- morula stage, suggesting that GRK2 may play an essential role during the early development of the porcine embryos. GRK2 knockdown reduced porcine embryo development capacity and led to significantly decreased blastocyst quality. In addition, inhibition of GRK2 also induced poor ability of embryo development at early stage, indicating that GRK2 is critical for embryonic cleavage in pigs. Knockdown and inhibition of GRK2 reduced HSP90 expression and AKT activation and cAMP levels. Additionally, GRK2 deficiency increased LC3 expression, suggesting enhanced autophagy during embryo development. In summary, we showed that GRK2 binds to HSP90 on the membrane to regulate embryonic cleavage and AKT activation during embryonic development in pigs.

13.
Org Biomol Chem ; 22(24): 4978-4986, 2024 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-38832762

RESUMEN

Ganoderma lucidum, a fungus used in traditional Chinese medicine, is known for its medicinal value attributed to its active components called Ganoderma triterpenoids (GTs). However, the limited isolation rate of these GTs has hindered their potential as promising drug candidates. Therefore, it is imperative to achieve large-scale preparation of GTs. In this study, four GTs were effectively synthesised from lanosterol. The antitumor activity of these GTs was evaluated in vivo. Endertiin B exhibited potent inhibitory activity against breast cancer cells (9.85 ± 0.91 µM and 12.12 ± 0.95 µM). Further investigations demonstrated that endertiin B significantly upregulated p21 and p27 and downregulated cyclinD1 expression, arresting the cell cycle at the G0/G1 phase and inducing apoptosis by decreasing BCL-2 and increasing BAX and BAK levels. Additionally, endertiin B was found to reduce the expression of proteins associated with the PI3K-AKT signaling pathway. To summarize, endertiin B effectively inhibited cell proliferation by blocking the cell cycle and inducing apoptosis through the PI3K-AKT pathway.


Asunto(s)
Antineoplásicos , Apoptosis , Proliferación Celular , Reishi , Triterpenos , Triterpenos/farmacología , Triterpenos/química , Triterpenos/síntesis química , Triterpenos/aislamiento & purificación , Reishi/química , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Proliferación Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Animales , Ratones , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Relación Estructura-Actividad , Femenino , Ciclo Celular/efectos de los fármacos , Estructura Molecular
14.
Environ Sci Technol ; 58(2): 1109-1118, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38164899

RESUMEN

Hygroscopic growth of adsorbed water films on clay particles underlies a number of environmental science questions, from the air quality and climate impacts of mineral dust aerosols to the hydrology and mechanics of unsaturated soils and sedimentary rocks. Here, we use molecular dynamics (MD) simulations to establish the relation between adsorbed water film thickness (h) and relative humidity (RH) or disjoining pressure (Π), which has long been uncertain due to factors including sensitivity to particle shape, surface roughness, and aqueous chemistry. We present a new MD simulation approach that enables precise quantification of Π in films up to six water monolayers thick. We find that the hygroscopicity of phyllosilicate mineral surfaces increases in the order mica < K-smectite < Na-smectite. The relationship between Π and h on clay surfaces follows a double exponential decay with e-folding lengths of 2.3 and 7.5 Å. The two decay length scales are attributed to hydration repulsion and osmotic phenomena in the electrical double layer (EDL) at the clay-water interface.


Asunto(s)
Minerales , Silicatos , Agua , Arcilla , Agua/química , Humectabilidad
15.
J Clin Nurs ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38887147

RESUMEN

AIM: The study was aimed at exploring the current scope of hospital to home transitional care programmes for stroke survivors. BACKGROUND: Stroke survivors face the dilemma of solving many complex problems that leave survivors at high risk for readmission as they discharge from hospital. The transitional care model has proved to be effective in reducing readmissions and mortality, thereby improving health outcomes and enhancing patient satisfaction for survivors with stroke. DESIGN: A scoping review. METHODS: Conducted in accordance with the Joanna Briggs Institute (JBI) Methodology for Scoping Reviews. DATA SOURCES: A comprehensive search was conducted in nine databases, including PubMed, Web of Science, Cochrane Library, EMBASE, CINAHL, Medline, China Knowledge Net-work, Wanfang Database and China Biomedical Literature Database (SinoMed) from January 2014 to June 2023. RESULTS: Title and abstract screening was performed on 10,171 articles resulting in 287 articles for full-text screening. Full-text screening yielded 49 articles that met inclusion criteria. CONCLUSION: This study identified transitional care programmes for stroke survivors, as well as areas for future consideration to be explored in more depth to help improve transitional care for stroke survivors as they transition from hospital to home. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: This study demonstrates that multidisciplinary collaboration becomes an integral part of the transitional care model for stroke survivors, which provides comprehensive and precise medical care to them. REPORTING METHOD: PRISMA checklist for scoping reviews. PATIENT AND PUBLIC CONTRIBUTION: No patient or public contribution was part of this study.

16.
J Environ Manage ; 364: 121472, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38879968

RESUMEN

Aquaculture systems are expected to act as potential hotspots for nitrous oxide (N2O) emissions, largely attributed to substantial nutrient loading from aquafeed applications. However, the specific patterns and contributions of N2O fluxes from these systems to the global emissions inventory are not well characterized due to limited data. This study investigates the patterns of N2O flux across 127 freshwater systems in China to elucidate the role of aquaculture ponds and lakes/reservoirs in landscape N2O emission. Our findings show that the average N2O flux from aquaculture ponds was 3.63 times higher (28.73 µg N2O m-2 h-1) than that from non-aquaculture ponds. Additionally, the average N2O flux from aquaculture lakes/reservoirs (15.65 µg N2O m-2 h-1) increased 3.05 times compared to non-aquaculture lakes/reservoirs. The transition from non-aquaculture to aquaculture practices has resulted in a net annual increase of 7589 ± 2409 Mg N2O emissions in China's freshwater systems from 2003 to 2022, equivalent to 20% of total N2O emissions from China's inland water. Particularly, the robust negative regression relationship between N2O emission intensity and water area suggests that small ponds are hotspots of N2O emissions, a result of both elevated nutrient concentrations and more vigorous biogeochemical cycles. This indicates that N2O emissions from smaller aquaculture ponds are larger per unit area compared to equivalent larger water bodies. Our findings highlight that N2O emissions from aquaculture systems can not be proxied by those from natural water bodies, especially small water bodies exhibiting significant but largely unquantified N2O emissions. In the context of the rapid global expansion of aquaculture, this underscores the critical need to integrate aquaculture into global assessments of inland water N2O emissions to advance towards a low-carbon future.


Asunto(s)
Acuicultura , Óxido Nitroso , Óxido Nitroso/análisis , China , Lagos , Monitoreo del Ambiente
17.
BMC Nurs ; 23(1): 226, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38566069

RESUMEN

BACKGROUND: Education has been recognised as necessary in forming and internalising professional values. The system and instructors' content in existing educational institutions focus on developing students' knowledge, skills and practices. Still, the development of values has yet to achieve significant effects, leading to a crisis in students' professional identity. AIMS: To construct a professional values growth theory for undergraduate nursing students and develop a corresponding education framework. METHODS: Through the review, some databases(PubMed、CINAHL、Web of Science、Wiley and Google Scholars)were searched using a systematic search strategy to collect relevant literature on professional values education. Based on the nursing professional values growth theory (Li and Li, Nursing Ethics In press, 2022), a theory of professional values growth of nursing undergraduates was developed using the method of theory derivation. Two rounds of expert meetings were conducted to review and revise an education framework of professional values of nursing undergraduates derived from that theory. FINDINGS: A total of 10 studies were included. The contents of two themes were analysed: theories and models and the current status of the professional values development of nursing students. The resulting professional values growth theory for undergraduate nursing students consists of five parts: key aspects, decisive opportunities, drivers, embodiment (humanistic sentiments, moral emotions), and outcomes. A total of five experts in the relevant fields were invited to this study. After two rounds of expert meetings, an education framework for undergraduate nursing students was finally developed, which consists of four parts: education objectives, education process and content, environment and conditions, and evaluation. CONCLUSION: The education framework developed in this study has practical implications for the development of professional values of undergraduate nursing students, providing educational strategies and methods for the growth and internalisation of professional values of undergraduate nursing students.

18.
BMC Nurs ; 23(1): 466, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982439

RESUMEN

BACKGROUND: Academic resilience is a crucial concept for nursing students to cope with academic challenges. Currently, there is significant variation in the description of the concept attributes of academic resilience among nursing students, which impedes the advancement of academic research. Therefore, it is essential to establish a clear definition of the concept of academic resilience for nursing students. PURPOSE: The purpose of this paper is to report the results of concept analysis of academic resilience of nursing students. METHODS: The Rodgers evolutionary concept analysis was employed to test the attributes, antecedents, consequences and related concepts of academic resilience of nursing students. Walker and Avant's method was utilized to construct a model case and provide empirical referents. RESULTS: The findings indicate that the attributes of nursing students' academic resilience include self-efficacy, self-regulation and recovery, and the antecedents include internal factors and external environmental factors. The consequences include adaptability, career maturity, adversity quotient level, probability of academic success, a sense of belonging to school and low levels of psychological distress. CONCLUSION: The systematic understanding of academic resilience among nursing students provides a pathway for nursing educators and students to enhance academic resilience, promote academic success, and establish a foundation for the training of more qualified nurses.

19.
Nurs Ethics ; : 9697330241266772, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39045912

RESUMEN

BACKGROUND: The formation of nursing professional values is crucial to the development of the nursing profession, but it is influenced by various factors. The process of shaping nursing professional values in different growth contexts has been overlooked. In order to establish professional values in the context of Chinese nursing, it is necessary to investigate the evolution of nursing professional values throughout history. PURPOSE: To develop a theory of professional values growth from a nursing context. Design: This study adopted a grounded theory approach from Strauss and Corbin. PARTICIPANTS: From November 2021 to March 2022, a total of 33 participants were included. METHODS: Data were collected using a semi-structured interview over telephone or online or face to face and were analysed using open, axial, and selective coding, with the help of MAXQDA 2020. ETHICAL CONSIDERATIONS: The research was approved by the Ethics Committee of the China Medical University. All participants signed the informed consent and agreed to be interviewed before the study. FINDINGS: The study has developed a theoretical construct of nursing professional values growth that consists of five dimensions: key aspects, decisive opportunities, drivers, embodiment, and shaping outcomes. And key aspects include four subcategories (the initial stage, the consciousness stage, the core stage, and the action stage). Decisive opportunities come from organisations and individuals. Drivers consist of social culture and self-trait, and embodiment covers two subcategories (humanism and ethical emotions). The last dimension is shaping outcomes, which consists of three subcategories (maintaining the original intention, professionalism, and instilling professional values). DISCUSSION: The theory demonstrates the individual development process of nursing professional values in different interactive contexts, the context of its interaction with social and personal values is revealed, and the dynamics and mechanisms of the formation of personal psychological qualities in professional values from a nursing context are discovered. CONCLUSIONS: This theory reveals the mechanisms that shape nursing professional values and can provide guidance for the growth of nursing students' professional values.

20.
J Cell Physiol ; 238(7): 1592-1604, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37204013

RESUMEN

Y-box binding protein 1 (YBX1) is a member of the family of DNA- and RNA-binding proteins that play crucial roles in multiple aspects, including RNA stabilization, translational repression, and transcriptional regulation; however, its roles in embryo development remain less known. In this study, to investigate the function of YBX1 and its mechanism of action in porcine embryo development, YBX1 was knocked down by microinjecting YBX1 siRNA at the one-cell stage. YBX1 is located in the cytoplasm during embryonic development. The mRNA level of YBX1 was increased from the four-cell stage to the blastocyst stage but was significantly decreased in YBX1 knockdown embryos compared with the control. Moreover, the percentage of blastocysts was decreased following YBX1 knockdown compared with the control. Defecting YBX1 expression increased maternal gene mRNA expression and decreased zygotic genome activation (ZGA) gene mRNA expression and histone modification owing to decreased levels of N6-methyladenosine (m6A) writer N6-adenosine-methyltransferase 70 kDa subunit (METTL3) and reader insulin-like growth factor 2 mRNA-binding protein (IGF2BP1). In addition, IGF2BP1 knockdown showed that YBX1 regulated the ZGA process through m6A modification. In conclusion, YBX1 is essential for early embryo development because it regulates the ZGA process.


Asunto(s)
Proteínas de Unión al ADN , Desarrollo Embrionario , Cigoto , Animales , Adenosina/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Porcinos , Cigoto/metabolismo , Proteínas de Unión al ADN/metabolismo
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