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1.
Nat Commun ; 15(1): 9024, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39424821

RESUMO

Studies on the piezoelectric materials capable of efficiently outputting high electrostrains at low electric fields are driven by the demand for precise actuation in a wide range of applications. Large electrostrains of piezoceramics in operation require high driving fields, which limits their practical application due to undesirable nonlinearities and high energy consumption. Herein, a strategy is developed to enhance the electrostrains of piezoceramics while maintaining low hysteresis by incorporating lead magnesium niobate relaxors into lead zirconate titanium at the morphotropic phase boundary. An ultrahigh inverse piezoelectric coefficient d 33 * of 1380 pm/V with a reduced hysteresis of 11.5% is achieved under a low electric field of 1 kV/mm, outperforming the major lead-based piezoelectric materials. In situ synchrotron X-ray diffraction and domain wall dynamics characterization with sub-microsecond temporal resolution reveal that the outstanding performances originate from facilitated domain wall movement, which in turn is due to reduced lattice distortion and miniaturized domain structures. These findings not only address the pending challenges of effective actuation under reduced driving conditions but also lay the foundation for a more systematic approach to exploring the origin of large electrostrains.

2.
JCI Insight ; 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39405117

RESUMO

Sepsis-induced acute lung injury (ALI) is prevalent in septic patients and has a high mortality rate. Peptidyl arginine deiminase (PADI) 2 and PADI4 play crucial roles in mediating the host's immune response in sepsis, but their specific functions remain unclear. Our study shows that Padi2-/-Padi4-/- double knockout (DKO) improved survival, reduced lung injury, decreased bacterial load in Pseudomonas aeruginosa (PA) pneumonia-induced sepsis mice. Using single-cell RNA sequencing (scRNA-seq), we found that the deletion of Padi2 and Padi4 reduced the Nlrp3+ pro-inflammatory macrophages and fostered Chil3+ myeloid cell differentiation into anti-inflammatory macrophages. Additionally, we observed the regulatory role of NLRP3-Ym1 axis upon DKO, confirmed by Chil3 knockdown and Nlrp3 KO experiments. Thus, eliminating Padi2 and Padi4 enhances the polarization of Ym1+ M2 macrophages by suppressing NLRP3, aiding in inflammation resolution and lung tissue repair. study unveils the PADI2/PADI4-NLRP3-Ym1 pathway as a potential target in treatment of sepsis-induced ALI.

3.
Cancer Biol Med ; 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39297568

RESUMO

Neutrophils, which originate from the bone marrow and are characterized by a segmented nucleus and a brief lifespan, have a crucial role in the body's defense against infections and acute inflammation. Recent research has uncovered the complex roles of neutrophils as regulators in tumorigenesis, during which neutrophils exhibit a dualistic nature that promotes or inhibits tumor progression. This adaptability is pivotal within the tumor microenvironment (TME). In this review, we provide a comprehensive characterization of neutrophil plasticity and heterogeneity, aiming to illuminate current research findings and discuss potential therapeutic avenues. By delineating the intricate interplay of neutrophils in the TME, this review further underscores the urgent need to understand the dual functions of neutrophils with particular emphasis on the anti-tumor effects to facilitate the development of effective therapeutic strategies against cancer.

4.
World J Emerg Med ; 15(5): 333-355, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39290598

RESUMO

In 2009, the World Health Organization included snakebite on the list of neglected tropical diseases, acknowledging it as a common occupational hazard for farmers, plantation workers, and others, causing tens of thousands of deaths and chronic physical disabilities every year. This guideline aims to provide practical information to help clinical professionals evaluate and treat snakebite victims. These recommendations are based on clinical experience and clinical research evidence. This guideline focuses on the following topics: snake venom, clinical manifestations, auxiliary examination, diagnosis, treatments, and prevention.

5.
Biomed Pharmacother ; 180: 117455, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39341076

RESUMO

INTRODUCTION: This study aims to evaluate the therapeutic effects of sodium octanoate (SO), a medium-chain fatty acid salt, on SIMD in a murine model and to explore its underlying mechanisms. METHODS: Male mice were subjected to sepsis models through two methods: intraperitoneal injection of lipopolysaccharide (LPS) and cecal ligation and punction (CLP). Mice received interval doses of SO every 2 hours or 4 hours for a total of six times or three times after LPS treatment. The relationship between SO and G protein-coupled receptor 84 (GPR84) was evaluated through GEO data analysis and molecular docking studies. DBA/2 mice were used to study the role of the GPR84 protein in the SO-mediated protection. Energy metabolomics was utilized to comprehensively assess the impact of SO on the levels of cardiac energy metabolic products in septic mice. histone modification identification techniques were used to further identify the specific sites of histone modification in the hearts of SO-treated septic mice. RESULTS: SO treatment significantly improved myocardial contractile function, restored the oxidative stress imbalance and enhanced the myocardium's resistance to oxidative injury. SO significantly promotes the expression of GPR84. The loss of GPR84 function markedly attenuates the protective effects of SO. SO enhanced myocardial energy metabolism by promoting the synthesis of acetyl-CoA and upregulating genes involved in fatty acid ß-oxidation which were abolished by medium-chain acyl-CoA dehydrogenase (MCAD) knockdown. SO induced histone acetylation, particularly at H3K123 and H3K80. CONCLUSION: Our study demonstrates that SO exerts protective effects against SIMD through both GPR84-mediated anti-inflammatory and antioxidant actions and GPR84-independent enhancement of myocardial energy metabolism, possibly mediated by MCAD.

6.
ACS Appl Mater Interfaces ; 16(39): 52299-52308, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39301663

RESUMO

Herein, the FeS2/TiO2 p-n heterojunction was first utilized as a photoelectrode for the PEC reduction of CO2 to selectively produce ethanol. The FeS2/TiO2 photoelectrode was fabricated through electrochemical anodization, electrodeposition, and vulcanization methods. The impact of the FeS2 loading amount and applied bias on the PEC performance was investigated. The behavior of photocurrent polarity reverse is observed depending on the FeS2 loading amount, which is related to the energy band structure of the semiconductor/electrolyte interface. The active sites for ethanol production were identified on TiO2 nanotubes rather than on the FeS2 surface. Incorporation of FeS2 not only broadened the visible light absorption range but also formed a p-n heterojunction with TiO2. FeS2/TiO2 with an electrodeposition time of 15 min exhibits the highest ethanol yield of 1170 µmol L-1 cm-2 for 3.5 h of reaction under ultraviolet-visible (UV-Vis) illumination at an applied bias of -0.7 V. Compared to TiO2, FeS2/TiO2 showed significantly higher ethanol yield due to its appropriate loading amount of FeS2 and the synergistic effect of strong UV-Vis light absorption and efficient separation and transfer of charge carriers at the p-n junction.

7.
Foods ; 13(17)2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39272620

RESUMO

The ratiometric fluorescent probe UiO-OH@Tb, a zirconium-based MOF functionalized with Tb3+, was synthesized using a hydrothermal method. This probe employs the fluorescence resonance energy transfer (FRET) mechanism between Tb3+ and malachite green (MG) for the double-inverse signal ratiometric fluorescence detection of MG. The probe's color shifts from lime green to blue with an increasing concentration of MG. In contrast, the monometallic MOFs' (UiO-OH) probe shows only blue fluorescence quenching due to the inner filter effect (IFE) after interacting with MG. Additionally, the composite fluorescent probe (UiO-OH@Tb) exhibits superior sensitivity, with a detection limit (LOD) of 0.19 µM, which is significantly lower than that of the monometallic MOFs (25 µM). Moreover, the content of MG can be detected on-site (LOD = 0.94 µM) using the RGB function of smartphones. Hence, the UiO-OH@Tb probe is proven to be an ideal material for MG detection, demonstrating significant practical value in real-world applications.

8.
Materials (Basel) ; 17(17)2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39274649

RESUMO

In this study, we developed well-aligned ZnO nanoflowers coated with poly-10,12-pentacosadiyonic acid (p-PCDA@ZnO) and modified with Pt nanoparticle (Pt/p-PCDA@ZnO) hybrid photoanodes for highly efficient photoelectrochemical (PEC) water splitting. The scanning electron microscope (SEM) image shows that thin films of the p-PCDA layer were well coated on the ZnO nanoflowers and that Pt nanoparticles were on it. The photoelectrochemical characterizations were made under simulated solar irradiation AM 1.5. The current density of the p-PCDA@ZnO and the Pt/p- PCDA@ZnO was 0.227 mA/cm2 and 0.305 mA/cm2, respectively, and these values were three times and four times higher compared to the 0.071 mA/cm2 of the bare ZnO nanoflowers. The UV-visible spectrum showed that the absorbance of coated p-PCDA films was extended in visible light region, which agrees with the enhanced PEC data for p-PCDA@ZnO. Also, adding Pt nanoparticles on top of the films as co-catalysts enhanced the PEC performance of Pt/p-PCDA@ZnO further. This indicates that Pt/p- PCDA@ZnO has a great potential to be implemented in solar water splitting.

9.
Biomed Pharmacother ; 179: 117408, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39244999

RESUMO

BACKGROUND: Ferroptosis is an important type of cell death contributing to myocardial dysfunction induced by whole body ischemia reperfusion following cardiac arrest (CA) and resuscitation. Sulforaphane (SFN), known as the activator of the nuclear factor E2-related factor 2 (Nrf2), has been proven to effectively alleviate regional myocardial ischemia reperfusion injury. The present study was designed to investigate whether SFN could improve post-resuscitation myocardial dysfunction by inhibiting cardiomyocytes ferroptosis and its potential regulatory mechanism. METHODS AND RESULTS: An in vivo pig model of CA and resuscitation was established. Hypoxia/reoxygenation (H/R)-stimulated AC16 cardiomyocytes was constructed as an in vitro model to simulate the process of CA and resuscitation. In vitro experiment, SFN reduced ferroptosis-related ferrous iron, lipid reactive oxygen species, and malondialdehyde, increased glutathione, and further promoted cell survival after H/R stimulation in AC16 cardiomyocytes. Mechanistically, the activation of Nrf2 with the SFN decreased interferon regulatory factor 1 (IRF1) expression, then reduced its binding to the promoter of glutathione peroxidase 4 (GPX4), and finally recovered the latter's transcription after H/R stimulation in AC16 cardiomyocytes. In vivo experiment, SFN reversed abnormal expression of IRF1 and GPX4, inhibited cardiac ferroptosis, and improved myocardial dysfunction after CA and resuscitation in pigs. CONCLUSIONS: SFN could effectively improve myocardial dysfunction after CA and resuscitation, in which the mechanism was potentially related to the inhibition of cardiomyocytes ferroptosis through the regulation of Nrf2/IRF1/GPX4 pathway.


Assuntos
Ferroptose , Fator Regulador 1 de Interferon , Isotiocianatos , Miócitos Cardíacos , Fator 2 Relacionado a NF-E2 , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Transdução de Sinais , Sulfóxidos , Animais , Ferroptose/efeitos dos fármacos , Isotiocianatos/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Sulfóxidos/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Suínos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fator Regulador 1 de Interferon/metabolismo , Fator Regulador 1 de Interferon/genética , Transdução de Sinais/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Linhagem Celular , Parada Cardíaca/tratamento farmacológico , Masculino , Modelos Animais de Doenças
10.
Phys Chem Chem Phys ; 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39120091

RESUMO

Standing at the forefront of energetics research is the exploration of energetic binders. To avoid the traditionally used sensitive explosophores, we present the first reported energetic silicone polymers synthesized from a penta-oxadiazole monomer. These polymers exhibit properties that lie between, or exceed, the thermal properties of inert and commonly used energetic binders.

11.
Materials (Basel) ; 17(16)2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39203288

RESUMO

Titanium carbide (TiC) coatings were prepared on the surface of AlFeCoCrNiCu high-entropy alloy blocks using electro-spark deposition (ESD). The microhardness and corrosion resistance of the TiC coatings prepared under different voltage and capacitance process parameters were studied. The research shows that the maximum microhardness of the TiC coating on sample 4 (working voltage of 20 V, working capacitance of 1000 µF) is 844.98 HV, which is 81.5% higher than the microhardness of the substrate. This is because the deposition energy increases with the increase in voltage, and the adhesion and aggregation between the coating and the substrate are enhanced, increasing the hardness of the coating. It is worth noting that excessive deposition energy can increase surface defects and reduce the microhardness of the coating surface. Electrochemical testing analysis shows that the corrosion current density of the TiC coating is the lowest (9.475 × 10-7 ± 0.06 × 10-7), and the coating impedance is the highest (2.502 × 103 Ω·com2). The absolute phase angle value is the highest (about 72°). The above indicates that the TiC coating prepared with a working voltage of 20 V and a working capacitance of 1000 µF has better microhardness and corrosion resistance.

12.
PLoS One ; 19(8): e0306653, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39146281

RESUMO

As medical education evolves, Problem-Based Learning (PBL) and Case-Based Learning (CBL) methodologies have emerged as vital pedagogical tools. This study aims to delve into the application and effectiveness of a hybrid PBL-CBL approach in clinical teaching for vascular surgery. By conducting a comparative analysis through concrete teaching practices, this research evaluates the impact on students' clinical knowledge retention, advancement in clinical reasoning skills, and proficiency in resolving real-world clinical challenges. The findings reveal that the integrated PBL-CBL methodology substantially enhances learning outcomes in vascular surgery clinical teaching, ultimately fostering significant development in students' comprehensive clinical abilities.


Assuntos
Aprendizagem Baseada em Problemas , Procedimentos Cirúrgicos Vasculares , Humanos , Procedimentos Cirúrgicos Vasculares/educação , Aprendizagem Baseada em Problemas/métodos , Estudantes de Medicina , Competência Clínica , Ensino , Feminino , Masculino , Educação Médica/métodos , Avaliação Educacional , Educação de Graduação em Medicina/métodos
13.
Sci Bull (Beijing) ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39183108

RESUMO

Morpholines are widespread in many biologically and catalytically active agents, thus being an important aim of pharmaceutical and synthetic chemists. However, efficient strategies for the catalytic asymmetric synthesis of chiral morpholines bearing crowded stereogenic centers still remain elusive. Herein, we disclose a Cu-catalyzed asymmetric propargylic amination/desymmetrization strategy to help resolve this challenge. As a result, two kinds of structurally various chiral morpholines bearing rich functional groups and N-α-quaternary stereocenters were produced with high efficiency and selectivity (42 examples, up to 91 % yield, 97:3 er and > 19:1 dr). In addition, a series of transformations were performed to demonstrate the synthetic utility of this methodology. In particular, a hit compound for new antitumor drugs was identified through cellular evaluation. Furthermore, mechanistic investigations reveal that, hydrogen bonding in the key copper-allenylidene intermediate together with π-π stacking aids remote enantioinduction.

14.
Immunology ; 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39183579

RESUMO

Hypoxia plays an important role in the metastasis of hepatocellular carcinoma (HCC). Exosomes have been widely studied as mediators of communication between tumours and immune cells. However, the specific mechanism by which hypoxic HCC cell-derived exosomes suppress antitumor immunity is unclear. Hypoxia scores were determined for The Cancer Genome-Liver Hepatocellular Carcinoma (TCGA-LIHC) dataset patients, and HCC patients in the hyperhypoxic group had a higher degree of M2 macrophage infiltration. Patients in the M2 high-invasion group had a lower probability of survival than those in the low-invasion group. In vivo and in vitro experiments demonstrated that exosomes secreted by hypoxic HCC cells promote M2 macrophage polarization. This polarization induces apoptosis in CD8+ T cells. Additionally, it encourages epithelial-mesenchymal transition (EMT), which increases HCC migration. Exosomal miRNA sequencing revealed that miR-1290 was highly expressed in exosomes secreted by hypoxic HCC cells. Mechanistically, miR-1290 in macrophages inhibited Akt2 while upregulating PD-L1 to promote M2 polarization, induce apoptosis in CD8+ T cells, and enhance EMT in HCC. Animal studies found that the miR-1290 antagomir in combination with the immune checkpoint inhibitor produced better antitumor effects than the monotherapies. In conclusion, the secretion of exosome-derived miR-1290 from HCC cells in a hypoxic environment supported immune escape by HCC cells by promoting M2 macrophage polarization to induce apoptosis in CD8+ T cells and enhance EMT that promoted HCC metastasis. Therefore, miR-1290 is an important molecule in antitumor immunity in HCC, and inhibition of miR-1290 could provide a novel immunotherapeutic approach for HCC treatment.

15.
Acta Biomater ; 186: 185-200, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39103136

RESUMO

Thrombosis and plasma leakage are two of the most frequent dysfunctions of polypropylene (PP) hollow fiber membrane (PPM) used in extracorporeal membrane oxygenation (ECMO) therapy. In this study, a superhydrophilic endothelial membrane mimetic coating (SEMMC) was constructed on polydopamine-polyethyleneimine pre-coated surfaces of the PPM oxygenator and its ECMO circuit to explore safer and more sustainable ECMO strategy. The SEMMC is fabricated by multi-point anchoring of a phosphorylcholine and carboxyl side chained copolymer (PMPCC) and grafting of heparin (Hep) to form PMPCC-Hep interface, which endows the membrane superior hemocompatibility and anticoagulation performances. Furthermore, the modified PPM reduces protein adsorption amount to less than 30 ng/cm2. More significantly, the PMPCC-Hep coated ECMO system extends the anti-leakage and non-clotting oxygenation period to more than 15 h in anticoagulant-free animal extracorporeal circulation, much better than the bare and conventional Hep coated ECMO systems with severe clots and plasma leakage in 4 h and 8 h, respectively. This SEMMC strategy of grafting bioactive heparin onto bioinert zwitterionic copolymer interface has great potential in developing safer and longer anticoagulant-free ECMO systems. STATEMENT OF SIGNIFICANCE: A superhydrophilic endothelial membrane mimetic coating was constructed on surfaces of polypropylene hollow fiber membrane (PPM) oxygenator and its ECMO circuit by multi-point anchoring of a phosphorylcholine and carboxyl side chain copolymer (PMPCC) and grafting of heparin (Hep). The strong antifouling nature of the PMPCC-Hep coating resists the adsorption of plasma bio-molecules, resulting in enhanced hemocompatibility and anti-leakage ability. The grafted heparin on the zwitterionic PMPCC interface exhibits superior anticoagulation property. More significantly, the PMPCC-Hep coating achieves an extracorporeal circulation in a pig model for at least 15 h without any systemic anticoagulant. This endothelial membrane mimetic anticoagulation strategy shows great potential for the development of safer and longer anticoagulant-free ECMO systems.


Assuntos
Materiais Revestidos Biocompatíveis , Oxigenação por Membrana Extracorpórea , Animais , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Heparina/química , Heparina/farmacologia , Humanos , Polipropilenos/química , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Fibrinolíticos/farmacologia , Fibrinolíticos/química , Membranas Artificiais , Adsorção , Trombose/prevenção & controle , Fosforilcolina/química , Fosforilcolina/análogos & derivados , Polímeros/química
16.
Artigo em Inglês | MEDLINE | ID: mdl-39020258

RESUMO

BACKGROUND: A major challenge in prevention and early treatment of acute kidney injury (AKI) is the lack of high-performance predictors in critically ill patients. Therefore, we innovatively constructed U-AKIpredTM for predicting AKI in critically ill patients within 12 h of panel measurement. METHODS: The prospective cohort study included 680 patients in the training set and 249 patients in the validation set. After performing inclusion and exclusion criteria, 417 patients were enrolled in the training set and 164 patients were enrolled in the validation set finally. AKI was diagnosed by Kidney Disease Improving Global Outcomes (KDIGO) criteria. RESULTS: Twelve urinary kidney injury biomarkers (mALB, IgG, TRF, α1MG, NAG, NGAL, KIM-1, L-FABP, TIMP2, IGFBP7, CAF22 and IL-18) exhibited good predictive performance for AKI within 12 h in critically ill patients. U-AKIpredTM, combined with three crucial biomarkers (α1MG, L-FABP and IGFBP7) by multivariate logistic regression analysis, exhibited better predictive performance for AKI in critically ill patients within 12 h than the other twelve kidney injury biomarkers. The area under the curve (AUC) of the U-AKIpredTM, as a predictor of AKI within 12 h, was 0.802 (95% CI: 0.771-0.833, P < 0.001) in the training set and 0.844 (95% CI: 0.792-0.896, P < 0.001) in validation cohort. A nomogram based on the results of the training and validation sets of U-AKIpredTM was developed which showed optimal predictive performance for AKI. The fitting effect and prediction accuracy of U-AKIpredTM was evaluated by multiple statistical indicators. To provide a more flexible predictive tool, the dynamic nomogram (https://www.xsmartanalysis.com/model/U-AKIpredTM) was constructed using a web-calculator. Decision curve analysis (DCA) and a clinical impact curve were used to reveal that U-AKIpredTM with the three crucial biomarkers had a higher net benefit than these twelve kidney injury biomarkers respectively. The net reclassification index (NRI) and integrated discrimination index (IDI) were used to improve the significant risk reclassification of AKI compared with the 12 kidney injury biomarkers. The predictive efficiency of U-AKIpredTM was better than the NephroCheck® when testing for AKI and severe AKI. CONCLUSION: U-AKIpredTM is an excellent predictive model of AKI in critically ill patients within 12 h and would assist clinicians in identifying those at high risk of AKI.

17.
Plant Signal Behav ; 19(1): 2383823, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-39066647

RESUMO

Sophora davidii is a cross-pollinated plant with important ecological protection and medicinal value in China, but its seed yield is low due to backward and nonstandard production technology. Therefore, we divide the flowering period of Sophora davidii into initial, full and final flowering period, measuring the floral morphology, pollen viability, stigma receptivity, nectar volume and nectar concentration, foraging behavior of pollinators, fertilization physiology, seed yield and quality through field observation and indoor testing to explore whether the flowering period affects the floral traits, pollinator behavior and seed production of plants. Our results revealed that the nectar volume, nectar concentration, pollen viability and stigma receptivity at full flowering period were the highest. The single visit time and visit time per flower of Chinese honey bees were the longest in the full flowering period, while the number of transfer, visit frequency and number of touching stigma were the least. The visiting number of the bees was the most and the most active in the full flowering period. The bees pollination not only improved the pollen amount, germination rate, pollen tube length and the ovule number of S. davidii, but also their effect was the most obvious in full flowering period. The principal component analysis showed that pollination by Chinese honey bees during the whole flowering period of S. davidii was the best way to produce seeds. We can conclude that flowering period affects flower traits, foraging behavior of pollinators, seed yield and quality of S. davidii.


Assuntos
Flores , Polinização , Sementes , Polinização/fisiologia , Flores/fisiologia , Animais , Sementes/fisiologia , Sementes/crescimento & desenvolvimento , Abelhas/fisiologia , Néctar de Plantas/metabolismo , Pólen/fisiologia
18.
Nat Commun ; 15(1): 6420, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080278

RESUMO

Re-poling of unexpected partially depoled piezoelectric materials conventionally needs to be first fully depoled through annealing above their Curie temperature to revive piezoelectric performances. Here, we investigated de-poling and re-poling of Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 single crystals under electric fields at room temperature. We found that alternating current electric fields with amplitudes near the coercive field at low frequencies (<10 Hz) can be employed to successfully depolarize poled crystals at room temperature. We also demonstrated a reversible polarization switching process with a relaxor-PbTiO3 single crystal ultrasound transducer without device performance degradations. This experimental observation is supported by phase-field simulation, showing that alternating current electric fields can readily induce de-poling at room temperature, while direct current electric fields induce a transient depoled state only within an uncontrollable short period of time. The findings suggest new strategies for unprecedented in-device tailoring of the polarization states of ferroelectric materials.

19.
Cell Host Microbe ; 32(9): 1536-1551.e6, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39084229

RESUMO

Candida albicans stably colonizes humans but is the leading cause of hospital-acquired fungemia. Traditionally, masking immunogenic moieties has been viewed as a tactic for immune evasion. Here, we demonstrate that C. albicans blocks type I interferon (IFN-I) signaling via translocating an effector protein Cmi1 into host cells. Mechanistically, Cmi1 binds and inhibits TANK-binding kinase 1 (TBK1) to abrogate IFN-regulatory factor 3 (IRF3) phosphorylation, thereby suppressing the IFN-I cascade. Murine infection with a cmi1 mutant displays an exaggerated IFN-I response in both kidneys and bone-marrow-derived macrophages, leading to rapid fungal clearance and host survival. Remarkably, the lack of CMI1 compromises gut commensalism and increases IFN-I response in mouse colonic cells. These phenotypes of cmi1 are rescued by the depletion of IFN-I receptor. This work establishes the importance of TBK1 inhibition in fungal pathogenesis and reveals that a human commensal-pathogenic fungus significantly impacts host immunity during gut colonization and infection via delivering effector proteins into host cells.


Assuntos
Candida albicans , Fator Regulador 3 de Interferon , Macrófagos , Proteínas Serina-Treonina Quinases , Animais , Humanos , Camundongos , Candida albicans/imunologia , Candida albicans/patogenicidade , Candidíase/imunologia , Candidíase/microbiologia , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Interações Hospedeiro-Patógeno , Evasão da Resposta Imune , Fator Regulador 3 de Interferon/metabolismo , Interferon Tipo I/metabolismo , Interferon Tipo I/imunologia , Rim/microbiologia , Rim/imunologia , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos Endogâmicos C57BL , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Simbiose
20.
Mikrochim Acta ; 191(8): 464, 2024 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007936

RESUMO

Rapid and high-sensitive Salmonella detection in milk is important for preventing foodborne disease eruption. To overcome the influence of the complex ingredients in milk on the sensitive detection of Salmonella, a dual-signal reporter red fluorescence nanosphere (RNs)-Pt was designed by combining RNs and Pt nanoparticles. After being equipped with antibodies, the immune RNs-Pt (IRNs-Pt) provide an ultra-strong fluorescence signal when excited by UV light. With the assistance of the H2O2/TMB system, a visible color change appeared that was attributed to the strong peroxidase-like catalytic activity derived from Pt nanoparticles. The IRNs-Pt in conjunction with immune magnetic beads can realize that Salmonella typhimurium (S. typhi) was captured, labeled, and separated effectively from untreated reduced-fat pure milk samples. Under the optimal experimental conditions, with the assay, as low as 50 CFU S. typhi can be converted to detectable fluorescence and absorbance signals within 2 h, suggesting the feasibility of practical application of the assay. Meanwhile, dual-signal modes of quantitative detection were realized. For fluorescence signal detection (emission at 615 nm), the linear correlation between signal intensity and the concentration of S. typhi was Y = 83C-3321 (R2 = 0.9941), ranging from 103 to 105 CFU/mL, while for colorimetric detection (absorbamce at 450 nm), the relationship between signal intensity and the concentration of S. typhi was Y = 2.9logC-10.2 (R2 = 0.9875), ranging from 5 × 103 to 105 CFU/mL. For suspect food contamination by foodborne pathogens, this dual-mode signal readout assay is promising for achieving the aim of convenient preliminary screening and accurate quantification simultaneously.


Assuntos
Colorimetria , Leite , Salmonella typhimurium , Leite/microbiologia , Leite/química , Salmonella typhimurium/isolamento & purificação , Colorimetria/métodos , Animais , Nanopartículas Metálicas/química , Limite de Detecção , Platina/química , Peróxido de Hidrogênio/química , Fluorescência , Nanosferas/química , Microbiologia de Alimentos/métodos , Contaminação de Alimentos/análise , Espectrometria de Fluorescência/métodos
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