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1.
Nat Mater ; 23(7): 944-950, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38783106

RESUMEN

Thin-film materials with large electromechanical responses are fundamental enablers of next-generation micro-/nano-electromechanical applications. Conventional electromechanical materials (for example, ferroelectrics and relaxors), however, exhibit severely degraded responses when scaled down to submicrometre-thick films due to substrate constraints (clamping). This limitation is overcome, and substantial electromechanical responses in antiferroelectric thin films are achieved through an unconventional coupling of the field-induced antiferroelectric-to-ferroelectric phase transition and the substrate constraints. A detilting of the oxygen octahedra and lattice-volume expansion in all dimensions are observed commensurate with the phase transition using operando electron microscopy, such that the in-plane clamping further enhances the out-of-plane expansion, as rationalized using first-principles calculations. In turn, a non-traditional thickness scaling is realized wherein an electromechanical strain (1.7%) is produced from a model antiferroelectric PbZrO3 film that is just 100 nm thick. The high performance and understanding of the mechanism provide a promising pathway to develop high-performance micro-/nano-electromechanical systems.

2.
Nat Mater ; 23(7): 898-904, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38622325

RESUMEN

A magnon is a collective excitation of the spin structure in a magnetic insulator and can transmit spin angular momentum with negligible dissipation. This quantum of a spin wave has always been manipulated through magnetic dipoles (that is, by breaking time-reversal symmetry). Here we report the experimental observation of chiral spin transport in multiferroic BiFeO3 and its control by reversing the ferroelectric polarization (that is, by breaking spatial inversion symmetry). The ferroelectrically controlled magnons show up to 18% modulation at room temperature. The spin torque that the magnons in BiFeO3 carry can be used to efficiently switch the magnetization of adjacent magnets, with a spin-torque efficiency comparable to the spin Hall effect in heavy metals. Utilizing such controllable magnon generation and transmission in BiFeO3, an all-oxide, energy-scalable logic is demonstrated composed of spin-orbit injection, detection and magnetoelectric control. Our observations open a new chapter of multiferroic magnons and pave another path towards low-dissipation nanoelectronics.

3.
Am J Pathol ; 194(8): 1458-1477, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38777148

RESUMEN

Idiopathic pulmonary fibrosis, a fatal interstitial lung disease, is characterized by fibroblast activation and aberrant extracellular matrix accumulation. Effective therapeutic development is limited because of incomplete understanding of the mechanisms by which fibroblasts become aberrantly activated. Here, we show aldehyde dehydrogenase 2 (ALDH2) in fibroblasts as a potential therapeutic target for pulmonary fibrosis. A decrease in ALDH2 expression was observed in patients with idiopathic pulmonary fibrosis and bleomycin-treated mice. ALDH2 deficiency spontaneously induces collagen accumulation in the lungs of aged mice. Furthermore, young ALDH2 knockout mice exhibited exacerbated bleomycin-induced pulmonary fibrosis and increased mortality compared with that in control mice. Mechanistic studies revealed that transforming growth factor (TGF)-ß1 induction and ALDH2 depletion constituted a positive feedback loop that exacerbates fibroblast activation. TGF-ß1 down-regulated ALDH2 through a TGF-ß receptor 1/Smad3-dependent mechanism. The subsequent deficiency in ALDH2 resulted in fibroblast dysfunction that manifested as impaired mitochondrial autophagy and senescence, leading to fibroblast activation and extracellular matrix production. ALDH2 overexpression markedly suppressed fibroblast activation, and this effect was abrogated by PTEN-induced putative kinase 1 (PINK1) knockdown, indicating that the profibrotic effects of ALDH2 are PINK1- dependent. Furthermore, ALDH2 activated by N-(1,3-benzodioxol-5-ylmethyl)-2,6-dichlorobenzamide (Alda-1) reversed the established pulmonary fibrosis in both young and aged mice. In conclusion, ALDH2 expression inhibited the pathogenesis of pulmonary fibrosis. Strategies to up-regulate or activate ALDH2 expression could be potential therapies for pulmonary fibrosis.


Asunto(s)
Aldehído Deshidrogenasa Mitocondrial , Bleomicina , Senescencia Celular , Fibroblastos , Ratones Noqueados , Mitocondrias , Animales , Fibroblastos/metabolismo , Fibroblastos/patología , Aldehído Deshidrogenasa Mitocondrial/metabolismo , Aldehído Deshidrogenasa Mitocondrial/genética , Aldehído Deshidrogenasa Mitocondrial/deficiencia , Ratones , Mitocondrias/metabolismo , Mitocondrias/patología , Humanos , Bleomicina/toxicidad , Bleomicina/efectos adversos , Factor de Crecimiento Transformador beta1/metabolismo , Ratones Endogámicos C57BL , Masculino , Fibrosis Pulmonar Idiopática/patología , Fibrosis Pulmonar Idiopática/metabolismo , Fibrosis Pulmonar Idiopática/genética , Fibrosis Pulmonar/patología , Fibrosis Pulmonar/metabolismo , Fibrosis Pulmonar/genética , Transducción de Señal , Pulmón/patología , Pulmón/metabolismo
4.
BMC Cancer ; 24(1): 208, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38360584

RESUMEN

BACKGROUND: Despite the known association between healthy lifestyles and reduced risk of breast cancer, it remains unclear whether systemic inflammation, as a consequence of unhealthy lifestyles, may mediate the association. METHODS: A cohort study of 259,435 female participants in the UK Biobank was conducted to estimate hazard ratio (HR) for breast cancer according to 9 inflammation markers using Cox regression models. We further estimated the percentage of total association between healthy lifestyle index (HLI) and breast cancer that is mediated by these inflammation markers. RESULTS: During 2,738,705 person-years of follow-up, 8,889 cases of breast cancer were diagnosed among 259,435 women in the UK Biobank cohort. Higher level of C-reactive protein (CRP), systemic immune-inflammation index (SII), CRP-to-albumin Ratio (CAR), CRP-to-lymphocyte Ratio (CLR), monocyte-to-HDL-c ratio (MHR), and neutrophil-to-HDL-c ratio (NHR) were associated with increased breast cancer risk, while a higher lymphocyte-to-monocyte ratio (LMR) was associated with a lower risk. The inverse association between HLI and breast cancer was weakly mediated by CRP (8.5%), SII (1.71%), CAR (8.66%), CLR (6.91%), MHR (6.27%), and NHR (7.33%). When considering individual lifestyle factors, CRP and CAR each mediated 16.58% and 17.20%, respectively, of the associations between diet score and breast cancer risk, while the proportion mediated for physical activity and breast cancer were 12.13% and 11.48%, respectively. Furthermore, MHR was found to mediate 13.84% and 12.01% of the associations between BMI, waist circumference, and breast cancer. CONCLUSION: The association of HLI and breast cancer is weakly mediated by the level of inflammation, particularly by CRP and CAR. Systemic inflammatory status may be an intermediate in the biological pathway of breast cancer development.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/etiología , Estudios de Cohortes , Análisis de Mediación , Inflamación/complicaciones , Proteína C-Reactiva/análisis , Estilo de Vida Saludable
5.
J Thromb Thrombolysis ; 57(1): 67-81, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37940761

RESUMEN

BACKGROUND: Accumulating evidence links the echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) rearrangement to venous thromboembolism (VTE) in non-small cell lung cancer (NSCLC) patients. However, the corresponding mechanisms remain unclear. METHOD: High-throughput sequencing analysis of H3122 human ALK-positive NSCLC cells treated with ALK inhibitor/ dimethyl sulfoxide (DMSO) was performed to identify coagulation-associated differential genes between EML4-ALK fusion protein inhibited cells and control cells. Sequentially, we confirmed its expression in NSCLC patients' tissues and in the plasma of a subcutaneous xenograft mouse model. An inferior vena cava (IVC) ligation model was used to assess clot formation potential. Additionally, pathways involved in tissue factor (TF) regulation were explored in ALK-positive cell lines H3122 and H2228. Statistical significance was determined by Student t-test and one-way ANOVA using SPSS. RESULTS: Sequencing analysis identified a significant downregulation of TF after inhibiting EML4-ALK fusion protein activity in H3122 cells. In clinical NSCLC cases, TF expression was increased especially in ALK-positive NSCLC tissues. Meanwhile, H3122 and H2228 with high TF expression exhibited shorter plasma clotting time and higher TF activity versus ALK-negative H1299 and A549 in cell culture supernatant. Mice bearing H2228 tumor showed a higher concentration of tumor-derived TF and TF activity in plasma and the highest adjusted IVC clot weights. Limiting EML4-ALK protein phosphorylation downregulated extracellular regulated protein kinases 1/2 (ERK1/2)-activating the protein-1(AP-1) signaling pathway and thus attenuated TF expression. CONCLUSION: EML4-ALK fusion protein may enhance venous thrombogenicity by regulating coagulation factor TF expression. There was potential involvement of the pERK1/2-AP-1 pathway in this process.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Animales , Ratones , Neoplasias Pulmonares/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Quinasa de Linfoma Anaplásico/genética , Quinasa de Linfoma Anaplásico/uso terapéutico , Tromboplastina/genética , Factor de Transcripción AP-1/uso terapéutico , Proliferación Celular , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/análisis , Proteínas de Fusión Oncogénica/metabolismo
6.
Eur Arch Otorhinolaryngol ; 281(8): 4191-4199, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38700538

RESUMEN

OBJECTIVE: Identifying the biomarkers for uncontrolled chronic rhinosinusitis (CRS) is important for directing treatment decisions. Eosinophilia has been reported to be involved in the poor disease control of CRS and mucus eosinophil-derived neurotoxin (EDN) is potentially a biomarker of intense eosinophil activation. This study aimed to assess the relationship between mucus EDN levels, disease severity, and degree of CRS control. METHODS: A total of 150 adult patients with CRS and 25 healthy controls were prospectively enrolled. The nasal mucus and tissue specimens were collected to analyze EDN levels. Disease severity was assessed by Lund-Mackay score and 22-item Sino-Nasal Outcome Test (SNOT-22) score. Five CRS symptom severities during the prior month (nasal blockage, rhinorrhoea/postnasal drip, facial pain/pressure, smell, sleep disturbance or fatigue), use of rescue medications in the last six months, and the presence of diseased mucosa on nasal endoscopy were obtained. Consistent with the European Position Paper on Rhinosinusitis and Nasal Polyps 2020 CRS control criteria, uncontrolled CRS was defined as meeting at least three items. RESULTS: 40% of patients with CRS presented with uncontrolled status. Patients with uncontrolled CRS had significantly higher nasal mucus EDN levels (P = 0.010), percentage of blood eosinophil (P = 0.015), SNOT-22 score (P < 0.001), Lund-Mackay score (P = 0.008), and a more eosinophilic dominant phenotype of CRS (P < 0.001) than patients with controlled CRS. Furthermore, mucus EDN levels were positively correlated with blood eosinophils (r = 0.541, P = 0.005), SNOT-22 score (r = 0.460, P = 0.021), and Lund-Mackay score (r = 0.387, P = 0.039). Mucus EDN levels were the significant parameter related to uncontrolled CRS in multivariable analysis after adjusting for patient demographics and comorbidities (odds ratio = 1.323; P = 0.004). CONCLUSIONS: Mucus EDN levels may be a potential biomarker for identifying the CRS control status.


Asunto(s)
Biomarcadores , Neurotoxina Derivada del Eosinófilo , Moco , Rinitis , Sinusitis , Humanos , Sinusitis/complicaciones , Sinusitis/metabolismo , Rinitis/metabolismo , Rinitis/complicaciones , Masculino , Femenino , Enfermedad Crónica , Persona de Mediana Edad , Adulto , Moco/metabolismo , Neurotoxina Derivada del Eosinófilo/metabolismo , Biomarcadores/metabolismo , Estudios Prospectivos , Estudios de Casos y Controles , Índice de Severidad de la Enfermedad , Mucosa Nasal/metabolismo , Prueba de Resultado Sino-Nasal , Anciano , Rinosinusitis
7.
Small ; 19(32): e2303214, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37170674

RESUMEN

It remains a challenge to develop efficient noble metal-free electrocatalysts for the oxygen reduction reaction (ORR) in various renewable energy systems. Single atom catalysts have recently drawn great attention as promising candidates both due to their high activity and their utmost atom utilization for electrocatalytic ORR. Herein, the synthesis of an efficient ORR electrocatalyst that is composed of N-doped mesoporous carbon and a high density (4.05 wt%) of single Fe atoms via pyrolysis Fe-conjugated polymer is reported. Benefiting from the abundant atomic Fe-N4 sites on its conductive, mesoporous carbon structures, this material exhibits an excellent electrocatalytic activity for ORR, with positive onset potentials of 0.93 and 0.98 V in acidic and alkaline media, respectively. Its electrocatalytic performance for ORR is also comparable to that of Pt/C (20 wt%) in both media. Furthermore, it electrocatalyzes the reaction almost fully to H2 O (or barely to H2 O2 ). Additionally, it is durable and tolerates the methanol crossover reaction well. Furthermore, a proton exchange membrane fuel cell and a zinc-air battery assembled using it on their cathode deliver high maximum power densities (320 and 91 mW cm-2 , respectively). Density functional theory calculation reveals that the material's decent electrocatalytic performance for ORR is due to its atomically dispersed Fe-N4 sites.

8.
J Transl Med ; 21(1): 166, 2023 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-36864526

RESUMEN

BACKGROUND: N6-methyladenosine (m6A) modification has been recognized to play fundamental roles in the development of autoimmune diseases. However, the implication of m6A modification in myasthenia gravis (MG) remains largely unknown. Thus, we aimed to systematically explore the potential functions and related immune characteristics of m6A regulators in MG. METHODS: The GSE85452 dataset with MG and healthy samples was downloaded from Gene Expression Omnibus (GEO) database. m6A modification regulators were manually curated. The targets of m6A regulators were obtained from m6A2Target database. The differential expressed m6A regulators in GSE85452 dataset were identified by "limma" package and were validated by RT-PCR. Function enrichment analysis of dysregulated m6A regulators was performed using "clusterProfiler" package. Correlation analysis was applied for analyzing the relationships between m6A regulators and immune characteristics. Unsupervised clustering analysis was used to identify distinct m6A modification subtypes. The differences between subtypes were analyzed, including the expression level of all genes and the enrichment degree of immune characteristics. Weighted gene co-expression network analysis (WGCNA) was conducted to obtain modules associated with m6A modification subtypes. RESULTS: We found that CBLL1, RBM15 and YTHDF1 were upregulated in MG samples of GSE85452 dataset, and the results were verified by RT-PCR in blood samples from19 MG patients and 19 controls. The targeted genes common modified by CBLL1, RBM15, and YTHDF1 were mainly enriched in histone modification and Wnt signaling pathway. Correlation analysis showed that three dysregulated m6A regulators were closely associated with immune characteristics. Among them, RBM15 possessed the strongest correlation with immune characteristics, including CD56dim natural killer cell (r = 0.77, P = 0.0023), T follicular helper cell (r = - 0.86, P = 0.0002), Interferon Receptor (r = 0.78, P = 0.0017), and HLA-DOA (r = 0.64, P = 0.0200). Further two distinct m6A modification patterns mediated by three dysregulated m6A regulators was identified. Bioinformatics analysis found that there were 3029 differentially expressed genes and different immune characteristics between two m6A modification patterns. Finally, WGCNA analysis obtained a total of 12 modules and yellow module was the most positively correlated to subtype-2. CONCLUSION: Our findings suggested that m6A RNA modification had an important effect on immunity molecular mechanism of MG and provided a new perspective into understanding the pathogenesis of MG.


Asunto(s)
Miastenia Gravis , Humanos , Miastenia Gravis/genética , Adenosina , Análisis por Conglomerados , Biología Computacional , Bases de Datos Factuales , Ubiquitina-Proteína Ligasas
9.
Phys Rev Lett ; 130(26): 266801, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37450818

RESUMEN

[BaTiO_{3}]_{m}/[BaZrO_{3}]_{n} (m, n=4-12) superlattices are used to demonstrate the fabrication and deterministic control of an artificial relaxor. X-ray diffraction and atomic-resolution imaging studies confirm the production of high-quality heterostructures. With decreasing BaTiO_{3} layer thickness, dielectric measurements reveal systematically lower dielectric-maximum temperatures, while hysteresis loops and third-harmonic nonlinearity studies suggest a transition from ferroelectriclike to relaxorlike behavior driven by tuning the random-field strength. This system provides a novel platform for studying the size effect and interaction length scale of the nanoscale-polar structures in relaxors.


Asunto(s)
Compuestos de Bario , Temperatura
10.
Ann Allergy Asthma Immunol ; 130(3): 317-324.e1, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35870756

RESUMEN

BACKGROUND: Eosinophils have been reported to be involved in the pathogenesis of olfactory fluctuation in chronic rhinosinusitis (CRS). Galectin-10 is more frequently associated with type 2 inflammation and potentially a sign of intense eosinophil activation. OBJECTIVE: To explore olfactory cleft mucus and olfactory mucosa galectin-10 level and its association with olfactory dysfunction (OD) in CRS. METHODS: We prospectively enrolled 50 patients with CRS and 15 healthy controls. Olfactory cleft mucus and superior turbinate biopsy specimens were collected to analyze galectin-10 levels and quantify tissue eosinophils. Psychophysical olfactory testing, olfactory cleft endoscopy scale, and olfactory cleft computed tomography scores were obtained. The predictability of galectin-10 levels for OD in patients with CRS was analyzed by multivariable logistic regression analysis. RESULTS: Both olfactory cleft mucus and olfactory mucosa galectin-10 levels in patients with CRS with OD were significantly higher than those in patients with CRS without OD (all P < .001). Mucus galectin-10 levels were positively correlated with tissue eosinophils (r = 0.541, P = 0.002), olfactory cleft endoscopy scale (r = 0.498, P = 0.006), and olfactory cleft computed tomography scores (r = 0.432, P = 0.019) in patients with CRS. Mucus galectin-10 levels were negatively correlated threshold, discrimination, and identification (r = -0.589,  P = 0.001), olfactory threshold (r = -0.522, P = 0.003), olfactory discrimination (r = -0.488, P = 0.007), and olfactory identification (r = -0.466, P = 0.011) scores. After adjusting for patient demographics and comorbidities, mucus galectin-10 levels were significantly associated with OD in patients with CRS (odds ratio, 1.299; P = .008). Mucus galectin-10 levels greater than 8.975 ng/mL were the best predictor of OD in CRS. CONCLUSION: Olfactory cleft mucus galectin-10 is highly associated with OD in CRS.


Asunto(s)
Pólipos Nasales , Trastornos del Olfato , Rinitis , Sinusitis , Humanos , Trastornos del Olfato/etiología , Olfato/fisiología , Enfermedad Crónica , Sinusitis/complicaciones , Moco , Galectinas
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