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1.
Polymers (Basel) ; 16(17)2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39274022

RESUMEN

Rare earth and transition metal ion-doped CaZnOS has garnered significant attention for its exceptional mechanoluminescence (ML) performance under mild mechanical stimuli and its capability for multicolor emissions. Since powdered phosphors are not directly usable, they require encapsulation within with polymers to create stable structures. This study investigates Mn2+-doped CaZnOS (CaZnOS:Mn2+) as the ML phosphor, optimizing its performance by varying the Mn2+ content, resulting in bright orange-red emissions from the d-d transitions of the Mn2+ activator. A quantum efficiency of 59.08% was achieved through the self-sensitization of the matrix lattice and energy transfer to the Mn2+ luminescent centers. The enhancement in ML due to Mn2+ doping is attributed to the reduced trap depth and increased trap concentration. Encapsulation with four polymers-PDMS, PU, SIL, and RTV-2-was explored to further optimize ML performance. Among these, PDMS provides the best ML output and sensitivity, owing to its slightly cross-linked structure and good triboelectric properties. The optimized CaZnOS:0.03Mn2+/PDMS composite, featuring excellent flexibility and recoverability, shows great potential for applications in anti-counterfeiting encryption, stress sensors, and wearable devices.

2.
EMBO J ; 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39294473

RESUMEN

Activation of the Toll-like receptor 4 (TLR4) by bacterial endotoxins in macrophages plays a crucial role in the pathogenesis of sepsis. However, the mechanism underlying TLR4 activation in macrophages is still not fully understood. Here, we reveal that upon lipopolysaccharide (LPS) stimulation, lysine acetyltransferase CBP is recruited to the TLR4 signalosome complex leading to increased acetylation of the TIR domains of the TLR4 signalosome. Acetylation of the TLR4 signalosome TIR domains significantly enhances signaling activation via NF-κB rather than IRF3 pathways. Induction of NF-κB signaling is responsible for gene expression changes leading to M1 macrophage polarization. In sepsis patients, significantly elevated TLR4-TIR acetylation is observed in CD16+ monocytes combined with elevated expression of M1 macrophage markers. Pharmacological inhibition of HDAC1, which deacetylates the TIR domains, or CBP play opposite roles in sepsis. Our findings highlight the important role of TLR4-TIR domain acetylation in the regulation of the immune responses in sepsis, and we propose this reversible acetylation of TLR4 signalosomes as a potential therapeutic target for M1 macrophages during the progression of sepsis.

3.
Int J Biol Macromol ; 278(Pt 2): 134812, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39163954

RESUMEN

The molecular mechanism of the formation of protein corona by the interaction of gold nanorods (AuNRs) with fibrinogen and transferrin was studied by spectroscopic methods and molecular docking. Studies have shown that AuNRs can be used as quencher to quench the fluorescence of fibrinogen/transferrin. The quenching mechanism mainly comes from static quenching. Fibrinogen has two different binding sites on the longitudinal and the transverse plane of AuNRs respectively, while transferrin has only one binding site on the surface of AuNRs. The adsorption process conforms to Freundlich adsorption isotherm and the pseudo-second-order reaction. The chemisorption is the rate-limiting step. Fibrinogen/transferrin may be a component of the "hard corona" because they bind AuNRs with high binding affinity. The formation of protein corona leads to a decrease in the hydrophobicity of the microenvironment around transferrin tryptophan (Trp) residues and an increase in the hydrophobicity of the microenvironment around fibrinogen/transferrin tyrosine (Tyr) residues, affecting the tertiary and secondary structure of fibrinogen/transferrin. Molecular docking can clearly see the specific amino acid residues of fibrinogen and transferrin adsorbed on AuNRs, and verify the experimental results.


Asunto(s)
Fibrinógeno , Oro , Simulación del Acoplamiento Molecular , Nanotubos , Unión Proteica , Corona de Proteínas , Transferrina , Oro/química , Transferrina/química , Transferrina/metabolismo , Nanotubos/química , Fibrinógeno/química , Fibrinógeno/metabolismo , Corona de Proteínas/química , Corona de Proteínas/metabolismo , Adsorción , Sitios de Unión , Interacciones Hidrofóbicas e Hidrofílicas , Humanos
4.
Plant J ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39167634

RESUMEN

As a dynamic and reversible post-transcriptional marker, N6-methyladenosine (m6A) plays an important role in the regulation of biological functions, which are mediated by m6A pathway components including writers (MT-A70, FIP37, VIR and HAKAI family), erasers (ALKBH family) and readers (YTH family). There is an urgent need for a comprehensive analysis of m6A pathway components across species at evolutionary levels. In this study, we identified 4062 m6A pathway components from 154 plant species including green algae, utilizing large-scale phylogenetic to explore their origin and evolution. We discovered that the copy number of writers was conserved among different plant lineages, with notable expansions in the ALKBH and YTH families. Synteny network analysis revealed conserved genomic contexts and lineage-specific transpositions. Furthermore, we used Direct RNA Sequencing (DRS) to reveal the Poly(A) length (PAL) and m6A ratio profiles in six angiosperms species, with a particular focus on the m6A pathway components. The ECT1/2-Poeaece4 sub-branches (YTH family) with unique genomic contexts exhibited significantly higher expression level than genes of other ECT1/2 poeaece sub-branches (ECT1/2-Poeaece1-3), accompanied by lower m6A modification and PAL. Besides, conserved m6A sites distributed in CDS and 3'UTR were detected in the ECT1/2-Poaceae4, and the dual-luciferase assay further demonstrated that these conserved m6A sites in the 3'UTR negatively regulated the expression of Firefly luciferase (LUC) gene. Finally, we developed transcription factor regulatory networks for m6A pathway components, using yeast one-hybrid assay demonstrated that PheBPC1 could interact with the PheECT1/2-5 promoter. Overall, this study presents a comprehensive evolutionary and functional analysis of m6A pathway components and their modifications in plants, providing a valuable resource for future functional analysis in this field.

5.
Int J Biol Macromol ; 277(Pt 2): 134238, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39084434

RESUMEN

Polydopamine has gained considerable attention in the biomaterial domain owing to its excellent biocompatibility, antioxidant activity, photothermal effect and adhesion property. Herein, copper sulfide (Cu2-xS) wrapped in mesoporous polydopamine (MPDA) was synthesized through in-situ polymerization, followed by the surface modification with cationic polyethyleneimine (PEI). The mussel-inspired MPDA matrix successfully prevented the oxidation and agglomeration of Cu2-xS nanoparticles, and regulated the release of copper ions and reactive oxygen species (ROS) levels. Surface-modified PEI endow MPDA@Cu2-xS with positive charges, facilitating their rapid contact with negatively charged bacteria through electrostatic interactions. The pH-dependent Cu+/Cu2+ release and NIR-responsive ROS generation were confirmed using molecular probes and electron spin resonance (ESR). The MPDA@Cu2-xS/PEI showed significantly enhanced antibacterial activity and reduced cytotoxicity for NIH3T3 cells. Under NIR irradiation (1.0 W/cm2, 10 min), germicidal efficiency against Escherichia coli (E. coli) and Staphyloccocus aureus (S. aureus) could reach 100 % and 99.94 %, respectively. The exceptional antibacterial activities of MPDA@Cu2-xS/PEI was mainly attributed to the synergistic photothermal effect, controlled release of copper ions and ROS generation, as well as electrostatic interaction. More importantly, the MPDA@Cu2-xS/PEI composite exhibited excellent biocompatibility and biosafety. Overall, this organic/inorganic hybrid holds great potential as a promising candidate for wound treatment.


Asunto(s)
Antibacterianos , Cobre , Escherichia coli , Indoles , Nanocompuestos , Polímeros , Especies Reactivas de Oxígeno , Staphylococcus aureus , Cobre/química , Cobre/farmacología , Indoles/química , Indoles/farmacología , Nanocompuestos/química , Polímeros/química , Polímeros/farmacología , Animales , Ratones , Antibacterianos/farmacología , Antibacterianos/química , Escherichia coli/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Staphylococcus aureus/efectos de los fármacos , Células 3T3 NIH , Porosidad , Rayos Infrarrojos , Sulfuros/química , Sulfuros/farmacología
6.
Oncol Rep ; 52(4)2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39054956

RESUMEN

Following the publication of this article, an interested reader drew to the authors' attention that the flow cytometric (FCM) plots in Fig. 2A on p. 2278 showing the 'Dasatinib' and 'CA­4' experiments were duplicates of each other. After having re­examined their original data, and due to the overall similarity of the data, the authors have realized that these data were inadvertently assembled incorrectly in the figure. They realize that they also made a further mistake regarding the writing of the ratios of mitochondrial membrane­depolarized HO­8910 cells for these FCM plots (essentially, these were written the wrong way around): The percentage of mitochondrial membrane­depolarized HO­8910 cells should have been written as 22.50% for the dasatinib­treated cells (the centre­left FCM plot) and 15.71% for the CA­4­treated cells (centre­right plot). A revised version of Fig. 2 now showing alternative data for the FCM experiments shown in Fig. 2A, is shown on the next page. Note that the errors made in terms of assembling the data in Fig. 2A did not greatly affect either the results or the conclusions reported in this paper, and all the authors agree with the publication of this corrigendum. The authors regret that these errors went unnoticed prior to the publication of their article, and are grateful to the Editor of Oncology Reports for granting them this opportunity to publish a corrigendum. Furthermore, they apologize to the readership for any inconvenience caused. [Oncology Reports 29: 2275­2282, 2013; DOI: 10.3892/or.2013.2405].

7.
Virol Sin ; 39(4): 587-599, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38823782

RESUMEN

Herpesviruses antagonize host antiviral responses through a myriad of molecular strategies culminating in the death of the host cells. Pseudorabies virus (PRV) is a significant veterinary pathogen in pigs, causing neurological sequalae that ultimately lead to the animal's demise. PRV is known to trigger apoptotic cell death during the late stages of infection. The virion host shutdown protein (VHS) encoded by UL41 plays a crucial role in the PRV infection process. In this study, we demonstrate that UL41 inhibits PRV-induced activation of inflammatory cytokine and negatively regulates the cGAS-STING-mediated antiviral activity by targeting IRF3, thereby inhibiting the translocation and phosphorylation of IRF3. Notably, mutating the conserved amino acid sites (E192, D194, and D195) in the RNase domain of UL41 or knocking down UL41 inhibits the immune evasion of PRV, suggesting that UL41 may play a crucial role in PRV's evasion of the host immune response during infection. These results enhance our understanding of how PRV structural proteins assist the virus in evading the host immune response.


Asunto(s)
Herpesvirus Suido 1 , Evasión Inmune , Factor 3 Regulador del Interferón , FN-kappa B , Herpesvirus Suido 1/inmunología , Herpesvirus Suido 1/genética , Factor 3 Regulador del Interferón/metabolismo , Factor 3 Regulador del Interferón/genética , Animales , Porcinos , FN-kappa B/metabolismo , FN-kappa B/genética , FN-kappa B/inmunología , Humanos , Interferones/inmunología , Interferones/metabolismo , Interferones/genética , Seudorrabia/virología , Seudorrabia/inmunología , Línea Celular , Interacciones Huésped-Patógeno/inmunología , Proteínas Virales/genética , Proteínas Virales/metabolismo , Proteínas Virales/inmunología , Células HEK293 , Fosforilación , Transporte de Proteínas
8.
Polymers (Basel) ; 16(11)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38891414

RESUMEN

In order to study the microscopic reaction mechanism and kinetic model of Al/PTFE, a reactive force field (ReaxFF) was used to simulate the interface model of the Al/PTFE system with different oxide layer thicknesses (0 Å, 5 Å, 10 Å), and the thermochemical behavior of Al/PTFE at different heating rates was analyzed by simultaneous thermal analysis (TG-DSC). The results show that the thickness of the oxide layer has a significant effect on the reaction process of Al/PTFE. In the system with an oxide layer thickness of 5 Å, the compactness of the oxide layer changes due to thermal rearrangement, resulting in the diffusion of reactants (fluorine-containing substances) through the oxide layer into the Al core. The reaction mainly occurs between the oxide layer and the Al core. For the 10 Å oxide layer, the reaction only exists outside the interface of the oxide layer. With the movement of the oxygen ions in the oxide layer and the Al atoms in the Al core, the oxide layer moves to the Al core, which makes the reaction continue. By analyzing the reaction process of Al/PTFE, the mechanism function of Al/PTFE was obtained by combining the shrinkage volume model (R3 model) and the three-dimensional diffusion (D3 model). In addition, the activation energy of Al/PTFE was 258.8 kJ/mol and the pre-exponential factor was 2.495 × 1015 min-1. The research results have important theoretical significance and reference value for the in-depth understanding of the microscopic chemical reaction mechanism and the quantitative study of macroscopic energy release of Al/PTFE reactive materials.

9.
mSphere ; 9(6): e0023624, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38757961

RESUMEN

Mammalian orthoreovirus (MRV) outer capsid protein σ3 is a multifunctional protein containing a double-stranded RNA-binding domain, which facilitates viral entry and assembly. We reasoned that σ3 has an innate immune evasion function. Here, we show that σ3 protein localizes in the mitochondria and interacts with mitochondrial antiviral signaling protein (MAVS) to activate the intrinsic mitochondria-mediated apoptotic pathway. Consequently, σ3 protein promotes the degradation of MAVS through the intrinsic caspase-9/caspase-3 apoptotic pathway. Moreover, σ3 protein can also inhibit the expression of the components of the RNA-sensing retinoic acid-inducible gene (RIG)-like receptor (RLR) signaling pathway to block antiviral type I interferon responses. Mechanistically, σ3 inhibits RIG-I and melanoma differentiation-associated gene 5 expression is independent of its inhibitory effect on MAVS. Overall, we demonstrate that the MRV σ3 protein plays a vital role in negatively regulating the RLR signaling pathway to inhibit antiviral responses. This enables MRV to evade host defenses to facilitate its own replication providing a target for the development of effective antiviral drugs against MRV. IMPORTANCE: Mammalian orthoreovirus (MRV) is an important zoonotic pathogen, but the regulatory role of its viral proteins in retinoic acid-inducible gene-like receptor (RLR)-mediated antiviral responses is still poorly understood. Herein, we show that MRV σ3 protein co-localizes with mitochondrial antiviral signaling protein (MAVS) in the mitochondria and promotes the mitochondria-mediated intrinsic apoptotic pathway to cleave and consequently degrade MAVS. Furthermore, tryptophan at position 133 of σ3 protein plays a key role in the degradation of MAVS. Importantly, we show that MRV outer capsid protein σ3 is a key factor in antagonizing RLR-mediated antiviral responses, providing evidence to better unravel the infection and transmission mechanisms of MRV.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Proteínas de la Cápside , Orthoreovirus de los Mamíferos , Transducción de Señal , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas de la Cápside/metabolismo , Proteínas de la Cápside/genética , Humanos , Orthoreovirus de los Mamíferos/genética , Animales , Apoptosis , Proteína 58 DEAD Box/metabolismo , Proteína 58 DEAD Box/genética , Mitocondrias/metabolismo , Inmunidad Innata , Ratones , Evasión Inmune , Células HEK293 , Receptores Inmunológicos/metabolismo , Helicasa Inducida por Interferón IFIH1/metabolismo , Helicasa Inducida por Interferón IFIH1/genética , Línea Celular , Interacciones Huésped-Patógeno
10.
Virol J ; 21(1): 107, 2024 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-38720392

RESUMEN

Natural immunity is the first defense line of the host immune system, which plays a significant role in combating foreign pathogenic microorganisms. The IFN-ß (interferon-beta) signaling pathway, being a typical example of innate immunity, plays a vital function. This study aimed to elucidate the function of pseudorabies virus (PRV) UL38 protein (unique long region 38) in suppressing the activation of the IFN-ß signaling pathway. The findings from our study indicate that the PRV UL38 protein effectively hampers the activation of IFN-ß by poly (dA: dT) (poly(deoxyadenylic-deoxythymidylic)) and 2'3'-cGAMP (2'-3'-cyclic GMP-AMP). Furthermore, UL38 exhibits spatial co-localization with STING (stimulator of interferon genes) and effectively hinders STING dimerization. Subsequently, STING was downgraded to suppress the production of IFN-ß and ISGs (interferon stimulated genes). Immunoprecipitation analysis revealed that the interaction between UL38 and STING, which subsequently initiated the degradation of STING via selective autophagy mediated by TOLLIP (toll interacting protein). To summarize, this research elucidates the function of UL38 in counteracting the cGAS (cGAMP synthase)-STING-induced IFN-ß pathway. The PRV UL38 protein may attenuate the activation of IFN-ß as a means of regulating the virus's persistence in the host.


Asunto(s)
Autofagia , Herpesvirus Suido 1 , Interferón beta , Proteínas de la Membrana , Nucleotidiltransferasas , Transducción de Señal , Animales , Humanos , Línea Celular , Células HEK293 , Herpesvirus Suido 1/fisiología , Herpesvirus Suido 1/inmunología , Interacciones Huésped-Patógeno , Inmunidad Innata , Interferón beta/metabolismo , Interferón beta/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/metabolismo , Nucleotidiltransferasas/metabolismo , Nucleotidiltransferasas/genética , Seudorrabia/virología , Seudorrabia/metabolismo , Seudorrabia/inmunología , Proteínas Virales/metabolismo , Proteínas Virales/genética , Porcinos , Mesocricetus
11.
Small Methods ; : e2400183, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38647122

RESUMEN

Improving the wide-temperature operation of rechargeable batteries is crucial for boosting the adoption of electric vehicles and further advancing their application scope in harsh environments like deep ocean and space probes. Herein, recent advances in electrolyte solvation chemistry are critically summarized, aiming to address the long-standing challenge of notable energy diminution at sub-zero temperatures and rapid capacity degradation at elevated temperatures (>45°C). This review provides an in-depth analysis of the fundamental mechanisms governing the Li-ion transport process, illustrating how these insights have been effectively harnessed to synergize with high-capacity, high-rate electrodes. Another critical part highlights the interplay between solvation chemistry and interfacial reactions, as well as the stability of the resultant interphases, particularly in batteries employing ultrahigh-nickel layered oxides as cathodes and high-capacity Li/Si materials as anodes. The detailed examination reveals how these factors are pivotal in mitigating the rapid capacity fade, thereby ensuring a long cycle life, superior rate capability, and consistent high-/low-temperature performance. In the latter part, a comprehensive summary of in situ/operational analysis is presented. This holistic approach, encompassing innovative electrolyte design, interphase regulation, and advanced characterization, offers a comprehensive roadmap for advancing battery technology in extreme environmental conditions.

12.
Spectrochim Acta A Mol Biomol Spectrosc ; 314: 124231, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38574610

RESUMEN

Hypochlorous acid (HClO), as an essential reactive oxygen species (ROS) in biological systems, plays a pivotal role in processes of physiology and pathology. Abnormal fluctuations in HClO concentration can lead to various diseases, such as inflammation, cardiovascular diseases, and neurodegeneration. Therefore, developing an approach to rapidly and sensitively quantify ClO- content is vital to biomedicine development and bioassays. Herein, we fabricated a novel "turn-on" label-free fluorescence DNA probe to specifically detect hypochlorite ion (ClO-) based on G-quadruplex formation. To this end, we designed a G-rich signal DNA sequence (S-DNA) and a block DNA sequence (B-DNA), followed by the introduction of ClO--responsive phosphorothioate (PS) into B-DNA. In the absence of ClO-, B-DNA hybridized with S-DNA, preventing G-quadruplex formation from S-DNA; this resulted in the relatively low fluorescence intensity of ThT. Once ClO- was added, the hydrolysis between PS and ClO- split the B-DNA into two fragments, resulting in B-DNA breaking away from S-DNA, allowing G-quadruplex formation from S-DNA and increasing the fluorescence intensity of ThT. Using this method, we can detect ClO- without the interference of additional reactive oxygen species. The detection limit of ClO- was as low as 10 nM. Furthermore, this method facilitates the detection of ClO- within the tissues of rats with stress-induced hypertension.


Asunto(s)
Benzotiazoles , Técnicas Biosensibles , ADN Forma B , G-Cuádruplex , Hipertensión , Humanos , Colorantes Fluorescentes , ADN , Técnicas Biosensibles/métodos , Ácido Hipocloroso
13.
Mol Immunol ; 170: 131-143, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38663254

RESUMEN

Mammalian reovirus (MRV) is a non-enveloped, gene segmented double-stranded RNA (dsRNA) virus. It is an important zoonotic pathogen that infects many mammals and vertebrates that act as natural hosts and causes respiratory and digestive tract diseases. Studies have reported that RIG-I and MDA5 in the innate immune cytoplasmic RNA-sensing RIG-like receptor (RLR) signaling pathway can recognize dsRNA from MRV and promote antiviral type I interferon (IFN) responses. However, the mechanism by which many MRV-encoded proteins evade the host innate immune response remains unclear. Here, we show that exogenous µ1 protein promoted the proliferation of MRV in vitro, while knockdown of MRV µ1 protein expression by shRNA could impair MRV proliferation. Specifically, µ1 protein inhibited MRV or poly(I:C)-induced IFN-ß expression, and attenuated RIG-I/MDA5-mediated signaling axis transduction during MRV infection. Importantly, we found that µ1 protein significantly decreased IFN-ß mRNA expression induced by MDA5, RIG-I, MAVS, TBK1, IRF3(5D), and degraded the protein expression of exogenous MDA5, RIG-I, MAVS, TBK1 and IRF3 via the proteasomal and lysosomal pathways. Additionally, we show that µ1 protein can physically interact with MDA5, RIG-I, MAVS, TBK1, and IRF3 and attenuate the RIG-I/MDA5-mediated signaling cascades by blocking the phosphorylation and nuclear translocation of IRF3. In conclusion, our findings reveal that MRV outer capsid protein µ1 is a key factor in antagonizing RLRs signaling cascades and provide new strategies for effective prevention and treatment of MRV infection.


Asunto(s)
Proteínas de la Cápside , Proteína 58 DEAD Box , Factor 3 Regulador del Interferón , Helicasa Inducida por Interferón IFIH1 , Orthoreovirus de los Mamíferos , Receptores Inmunológicos , Transducción de Señal , Animales , Humanos , Transporte Activo de Núcleo Celular , Núcleo Celular/metabolismo , Proteína 58 DEAD Box/metabolismo , Células HEK293 , Inmunidad Innata/inmunología , Factor 3 Regulador del Interferón/metabolismo , Interferón beta/metabolismo , Interferón beta/inmunología , Helicasa Inducida por Interferón IFIH1/metabolismo , Helicasa Inducida por Interferón IFIH1/genética , Orthoreovirus de los Mamíferos/inmunología , Orthoreovirus de los Mamíferos/fisiología , Fosforilación , Proteínas Serina-Treonina Quinasas , Infecciones por Reoviridae/inmunología , Transducción de Señal/inmunología , Proteínas Virales/metabolismo , Proteínas de la Cápside/metabolismo
14.
Environ Pollut ; 346: 123587, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38367695

RESUMEN

The turbocharged Miller cycle strategy is studied to improve the power density of diesel engines and reduce emissions. A thermodynamic model and a 1D simulation model of turbocharged diesel engine are established. Results show that the introduction of the Miller cycle reduces the thermal efficiency under naturally aspirated conditions because of the low effective compression ratio, whereas it increases the thermal efficiency under a turbocharged condition owing to the energy recovered by the turbocharger. Under restricted combustion pressure and fixed intake mass, the thermal efficiency first increases and then decreases with increasing Miller cycle ratio, and the peaks occur at approximately 30%-50%. The gain of isochoric combustion ratio overlaps the loss of effective compression ratio due to the Miller cycle on the lower side, whereas it reverses on the higher side. With maximum and equal intake mass, the maximum power initially increases and subsequently decreases with increasing Miller cycle ratio, reaching a peak at 40%. Under a fixed isochoric combustion ratio, the thermal efficiency first increases and then decreases with increasing intake mass, and the optimum intake mass corresponding to the highest thermal efficiency decreases with increasing Miller cycle ratio. The lower the restricted combustion pressure is, the higher the gain in power and thermal efficiency by the Miller cycle strategy. Based on the calculation of the 1D model validated using a practical engine, the power can be increased from 41.6 kW/L to 100 kW/L while the brake thermal efficiency can be increased from 34.98% into 38.55% by increasing the Miller cycle ratio from 19% to 30% and the combustion pressure from 17.7 MPa to 35 MPa. With the application of the supercharged Miller cycle, when the Miller cycle ratio is 30% and the power intensity is increased from 60 kW/L to 100 kW/L, NOx decreases by 32.4%, CO decreases by 28%, showing a tendency to decrease and then stabilize, and HC increases by 5.3%. When the power is 80 kW/L and the Miller cycle ratio is increased from 10% to 30%, NOx decreases by 8.6%, CO decreases by 2%, and HC increases by 0.04%.


Asunto(s)
Gasolina , Emisiones de Vehículos , Termodinámica , Biocombustibles , Monóxido de Carbono/análisis
15.
Viruses ; 16(2)2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38399950

RESUMEN

Histone H1.2 is a member of the linker histone family, which plays extensive and crucial roles not only in the regulation of chromatin dynamics, cell cycle, and cell apoptosis, but also in viral diseases and innate immunity response. Recently, it was discovered that H1.2 regulates interferon-ß and inhibits influenza virus replication, whereas its role in other viral infections is poorly reported. Here, we first found the up-regulation of H1.2 during Encephalomyocarditis virus (EMCV) infection, implying that H1.2 was involved in EMCV infection. Overexpression of H1.2 inhibited EMCV proliferation, whereas knockdown of H1.2 showed a significant promotion of virus infection in HEK293T cells. Moreover, we demonstrated that overexpression of H1.2 remarkably enhanced the production of EMCV-induced type I interferon, which may be the crucial factor for H1.2 proliferation-inhibitory effects. We further found that H1.2 up-regulated the expression of the proteins of the MDA5 signaling pathway and interacted with MDA5 and IRF3 in EMCV infection. Further, we demonstrated that H1.2 facilitated EMCV-induced phosphorylation and nuclear translocation of IRF3. Briefly, our research uncovers the mechanism of H1.2 negatively regulating EMCV replication and provides new insight into antiviral targets for EMCV.


Asunto(s)
Virus de la Encefalomiocarditis , Histonas , Humanos , Células HEK293 , Inmunidad Innata , Helicasa Inducida por Interferón IFIH1/genética , Transducción de Señal , Replicación Viral
16.
BMC Womens Health ; 24(1): 6, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38166898

RESUMEN

Breast cancer (BC) is a prominent cause of cancer incidence and mortality around the world. Disulfidptosis, a type of cell death, can induce tumor cell death. The purpose of this study was to analyze the potential impact of disulfidptosis-related genes (DRGs) on the prognosis and immune infiltration features of BC. Based on DRGs, we conducted an unsupervised clustering analysis on gene expression data of BC in TCGA-BRCA dataset and identified two BC subtypes, cluster1 and cluster2, with cluster1 showing a higher likelihood of favorable survival. Through immune analysis, we found that cluster1 had lower proportions of infiltration in immune-related cells, including aDCs, DCs, NK_cells, Th2_cells, and Treg. Based on the immunophenoscore (IPS) results, we inferred that cluster1 might benefit more from immune checkpoint inhibitors targeting CTLA-4 and PD1. Targeted small molecule prediction results showed that patients with cluster2 BC might respond better to antagonistic small molecule compounds, including clofazimine, lenalidomide, and epigallocatechin. Differentially expressed genes between the two subtypes were found to be enriched in signaling pathways related to steroid hormone biosynthesis, ovarian steroidogenesis, and neutrophil extracellular trap formation, according to enrichment analyses. In conclusion, this study identified BC subtypes based on DRGs so as to help predict patient prognosis and provide valuable tools for guiding clinical management and precise treatment of BC patients.


Asunto(s)
Neoplasias de la Mama , Inhibidores de Puntos de Control Inmunológico , Inmunoterapia , Femenino , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/terapia , Análisis por Conglomerados , Pronóstico , Expresión Génica
17.
Cell Death Dis ; 15(1): 57, 2024 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-38228583

RESUMEN

Osteosarcoma (OS) is a highly aggressive form of bone cancer that predominantly affects adolescents and young adults. In this study, we have undertaken an investigation into the potential anti-OS cell activity of IMT1 (inhibitor of mitochondrial transcription 1), a first-in-class inhibitor of RNA polymerase mitochondrial (POLRMT). IMT1 exhibited a profound inhibitory effect on cell survival, proliferation, cell cycle progression, and migration in primary and immortalized OS cells. Furthermore, this POLRMT inhibitor elicited apoptosis in the OS cells, without, however, inducing cytotoxicity in human osteoblasts or osteoblastic cells. IMT1 disrupted mitochondrial functions in OS cells, resulting in mitochondrial depolarization, oxidative injury, lipid peroxidation, and ATP reduction in OS cells. Silencing POLRMT using targeted shRNA closely mimicked the actions of IMT1 and exerted potent anti-OS cell activity. Importantly, IMT1's effectiveness was diminished in POLRMT-silenced OS cells. Subsequent investigations revealed that IMT1 suppressed the activation of the Akt-mammalian target of rapamycin (mTOR) cascade in OS cells. IMT1 treatment or POLRMT silencing in primary OS cells led to a significant reduction in Akt1-S6K-S6 phosphorylation. Conversely, it was enhanced upon POLRMT overexpression. The restoration of Akt-mTOR activation through the introduction of a constitutively active S473D mutant Akt1 (caAkt1) mitigated IMT1-induced cytotoxicity in OS cells. In vivo, oral administration of IMT1 robustly curtailed the growth of OS xenografts in nude mice. Furthermore, IMT1 suppressed POLRMT activity, impaired mitochondrial function, repressed Akt-mTOR activation, and induced apoptosis within xenograft tissues. Collectively, these findings underscore the potent growth-inhibitory effects attributed to IMT1 via targeted POLRMT inhibition. The utilization of this POLRMT inhibitor carries substantial therapeutic promise in the context of OS treatment.


Asunto(s)
Neoplasias Óseas , Osteosarcoma , Animales , Ratones , Adolescente , Adulto Joven , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratones Desnudos , Línea Celular Tumoral , Serina-Treonina Quinasas TOR/metabolismo , Osteosarcoma/genética , Sirolimus/farmacología , Apoptosis , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/metabolismo , Proliferación Celular , Mitocondrias/metabolismo , Mamíferos , ARN Polimerasas Dirigidas por ADN
18.
Front Pharmacol ; 14: 1123945, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37663258

RESUMEN

Objective: The effect of oxygen therapy on the prognosis of chronic obstructive pulmonary disease (COPD) with nocturnal hypoxemia (NOD) has been controversial. Therefore, this study systematically evaluated the relevant literature and included it into randomized controlled studies for meta-analysis to evaluate the efficacy and prognosis. Methods: We searched PubMed, EMBASE, web of science, Cochrane, China HowNet and Wanfang database for the literature on the prognosis of COPD patients with simple NOD from the establishment of the database to 30 June 2022. The outcome indicators were death and aggravation of the disease. The efficacy evaluation measures were pulmonary function and arterial blood gas results. The publication bias and heterogeneity of the included studies were evaluated. Results: A total of 621 patients from 5 studies were included in this meta-analysis, and there was no publication bias in the included studies. The total mortality of long-term oxygen therapy (LTOT) in COPD patients with simple NOD in oxygen therapy group (RR = 1.04; 95% CI: 0.81-1.33, p = 0.77), mortality (RR = 0.87; 95% CI: 0.58-1.31, p = 0.50), risk of progression to LTOT events (RR = 1.07; 95% CI: 0.76-1.51, p = 0.71). PaO2 in patients with COPD and simple NOD in oxygen therapy group was higher than that in non-oxygen therapy group (mean difference (MD) = 13.47; 95% CI: 3.49-23.46, p = 0.008), the decrease of PaCO2 level was not statistically significant (MD = -10.05; 95% CI: -26.36-6.27, p = 0.23). Conclusion: Oxygen therapy can improve the prognosis of blood oxygen partial pressure in COPD patients with simple NOD, but oxygen therapy has no significant effect on the survival rate, controlling the progression of the disease to LTOT and reducing the partial pressure of carbon dioxide.

19.
Polymers (Basel) ; 15(18)2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37765558

RESUMEN

Covalent organic frameworks (COFs) have gained considerable attention due to their highly conjugated π-skeletons, rendering them promising candidates for the design of light-emitting materials. In this study, we present two vinylene-linked COFs, namely, VL-COF-1 and VL-COF-2, which were synthesized through the Knoevenagel condensation of 2,4,6-trimethyl-1,3,5-triazine with terephthalaldehyde or 4,4'-biphenyldicarboxaldehyde. Both VL-COF-1 and VL-COF-2 exhibited excellent chemical and thermal stability. The presence of vinylene linkages between the constituent building blocks in these COFs resulted in broad excitation and emission properties. Remarkably, the designed VL-COFs demonstrated bright emission, fast fluorescence decay, and high stability, making them highly attractive for optoelectronic applications. To assess the potential of these VL-COFs in practical devices, we fabricated white-light-emitting diodes (WLEDs) coated with VL-COF-1 and VL-COF-2. Notably, the WLEDs coated with VL-COF-1 achieved high-quality white light emission, closely approximating standard white light. The promising performance of VL-COF-coated WLEDs suggests the feasibility of utilizing COF materials for stable and efficient lighting applications.

20.
Int J Biol Macromol ; 253(Pt 4): 127074, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37769767

RESUMEN

In this work, four structurally similar flavonols (galangin, kaempferol, quercetin and myricetin) were coated on the surface of (11-mercaptoundecyl)-N,N,N-trimethylammonium bromide (MUTAB)­gold nanoparticles (AuNPs) by two-step phase transfer and self-assembly, and the cationic MUTAB- AuNPs coated with flavonols (flavonol-MUTAB-AuNPs) were designed. Free radical scavenging and antibacterial experiments show that flavonol-MUTAB-AuNPs greatly improve the scavenging effect on DPPH, hydroxyl and superoxide anion radicals, and significantly enhance the inhibition effect on Staphylococcus aureus and Escherichia coli compared with flavonols and AuNPs. Then γ-globulin, fibrinogen, trypsin and pepsin were selected as representative proteins and their interaction with flavonol-MUTAB-AuNPs were investigated by various spectroscopic techniques. The fluorescence quenching mechanism of these four proteins by flavonol-MUTAB-AuNPs is static quenching. The binding constants Ka between them are in the range of 103 to 106. The interaction between them is endothermic, entropy-driven spontaneous process, and the main non-covalent force is the hydrophobic interaction. The effect of flavonol-MUTAB-AuNPs on the structure of the four proteins were investigated using UV-vis absorption spectra, synchronous fluorescence spectra and circular dichroism spectra. These results offer important insights into the essence of the interaction between flavonol-MUTAB-AuNPs and γ-globulin/fibrinogen/trypsin/pepsin. They will contribute to the development of safe and effective flavonol-MUTAB-AuNPs in biomedical fields.


Asunto(s)
Oro , Nanopartículas del Metal , Oro/química , Antioxidantes/farmacología , Antioxidantes/química , Pepsina A , Tripsina , Nanopartículas del Metal/química , Flavonoles/química , Antibacterianos/farmacología , Fibrinógeno , gammaglobulinas
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