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1.
Proc Natl Acad Sci U S A ; 121(16): e2322415121, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38602918

RESUMEN

Localized deformation and randomly shaped imperfections are salient features of buckling-type instabilities in thin-walled load-bearing structures. However, it is generally agreed that their complex interactions in response to mechanical loading are not yet sufficiently understood, as evidenced by buckling-induced catastrophic failures which continue to today. This study investigates how the intimate coupling between localization mechanisms and geometric imperfections combine to determine the statistics of the pressure required to buckle (the illustrative example of) a hemispherical shell. The geometric imperfections, in the form of a surface, are defined by a random field generated over the nominally hemispherical shell geometry, and the probability distribution of the buckling pressure is computed via stochastic finite element analysis. Monte-Carlo simulations are performed for a wide range of the shell's radius to thickness ratio, as well as the correlation length of the spatial distribution of the imperfection. The results show that over this range, the buckling pressure is captured by the Weibull distribution. In addition, the analyses of the deformation patterns observed during the simulations provide insights into the effects of certain characteristic lengths on the local buckling that triggers global instability. In light of the simulation results, a probabilistic model is developed for the statistics of the buckling load that reveals how the dimensionless radius plays a dual role which remained hidden in previous deterministic analyses. The implications of the present model for reliability-based design of shell structures are discussed.

2.
Nano Lett ; 24(5): 1687-1694, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38253561

RESUMEN

Revealing the in-depth structure-property relationship and designing specific capacity electrodes are particularly important for supercapacitors. Despite many efforts made to tune the composition and electronic structure of cobalt oxide for pseudocapacitance, insight into the [CoO]6 octahedron from the microstructure is still insufficient. Herein, we present a tunable [CoO]6 octahedron microstructure in LiCoO2 by a chemical delithiation process. The c-strained strain of the [CoO]6 octahedron is induced to form higher valence Co ions, and the (003) crystalline layer spacing increases to allow more rapid participation of OH- in the redox reaction. Interestingly, the specific capacity of L0.75CO2 is nearly four times higher than that of LiCoO2 at 10 mA g-1. The enhanced activity originated from the asymmetric strain [CoO]6 octahedra, resulting in enhanced electronic conductivity and Co-O hybridization for accelerated redox kinetics. This finding provides new insights into the modification strategy for pseudocapacitive transition metal oxides.

3.
Mol Cancer ; 23(1): 113, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38802795

RESUMEN

BACKGROUND: The role of circRNAs in hepatocellular carcinoma (HCC) progression remains unclear. CircPIAS1 (circBase ID: hsa_circ_0007088) was identified as overexpressed in HCC cases through bioinformatics analysis. This study aimed to investigate the oncogenic properties and mechanisms of circPIAS1 in HCC development. METHODS: Functional analyses were conducted to assess circPIAS1's impact on HCC cell proliferation, migration, and ferroptosis. Xenograft mouse models were employed to evaluate circPIAS1's effects on tumor growth and pulmonary metastasis in vivo. Bioinformatics analysis, RNA immunoprecipitation, and luciferase reporter assays were utilized to elucidate the molecular pathways influenced by circPIAS1. Additional techniques, including RNA pulldown, fluorescence in situ hybridization (FISH), chromatin immunoprecipitation (ChIP), qPCR, and western blotting, were used to further explore the underlying mechanisms. RESULTS: CircPIAS1 expression was elevated in HCC tissues and cells. Silencing circPIAS1 suppressed HCC cell proliferation and migration both in vitro and in vivo. Mechanically, circPIAS1 overexpression inhibited ferroptosis by competitively binding to miR-455-3p, leading to upregulation of Nuclear Protein 1 (NUPR1). Furthermore, NUPR1 promoted FTH1 transcription, enhancing iron storage in HCC cells and conferring resistance to ferroptosis. Treatment with ZZW-115, an NUPR1 inhibitor, reversed the tumor-promoting effects of circPIAS1 and sensitized HCC cells to lenvatinib. CONCLUSION: This study highlights the critical role of circPIAS1 in HCC progression through modulation of ferroptosis. Targeting the circPIAS1/miR-455-3p/NUPR1/FTH1 regulatory axis may represent a promising therapeutic strategy for HCC.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Carcinoma Hepatocelular , Proliferación Celular , Ferroptosis , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas , MicroARNs , Proteínas de Neoplasias , ARN Circular , Animales , Femenino , Humanos , Masculino , Ratones , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Progresión de la Enfermedad , Ferroptosis/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , MicroARNs/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , ARN Circular/genética , Ensayos Antitumor por Modelo de Xenoinjerto
4.
Br J Cancer ; 130(8): 1356-1364, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38355839

RESUMEN

BACKGROUND: We aimed to redefine Immune checkpoint inhibitors (ICIs)-responsive "hot" TME and develop a corresponding stratification model to maximize ICIs-efficacy in Hepatocellular Carcinoma (HCC). METHODS: Hypoxic scores were designed, and the relevance to immunotherapy responses were validated in pan-cancers through single cell analysis. Multi-omics analysis using the hypoxic scores and immune infiltrate abundance was performed to redefine the ICIs-responsive TME subtype in HCC patients from TCGA (n = 363) and HCCDB database (n = 228). The immune hypoxic stress index (IHSI) was constructed to stratify the ICIs-responsive TME subtype, with exploring biological mechanism in vitro and in vivo. MRI-radiomics models were built for clinical applicability. RESULTS: The hypoxic scores were lower in the dominant cell-subclusters of responders in pan-cancers. The higher immune infiltrate-normoxic (HIN) subtype was redefined as the ICIs-responsive TME. Stratification of the HIN subtype using IHSI effectively identified ICIs-responders in Melanoma (n = 122) and urological cancer (n = 22). TRAF3IP3, the constituent gene of IHSI, was implicated in ICIs-relevant "immune-hypoxic" crosstalk by stimulating MAVS/IFN-I pathway under normoxic condition. MRI-radiomics models assessing TRAF3IP3 with HIF1A expression (AUC > 0.80) screened ICIs-Responders in HCC cohort (n = 75). CONCLUSION: The hypoxic-immune stratification redefined ICIs-responsive TME and provided MRI-Radiomics models for initial ICIs-responders screening, with IHSI facilitating further identification.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/genética , Radiómica , Microambiente Tumoral , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Hipoxia , Imagen por Resonancia Magnética
5.
Cancer Immunol Immunother ; 73(3): 55, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38366287

RESUMEN

BACKGROUND: For patients with unresectable locally advanced esophageal squamous cell carcinoma (ESCC), concurrent chemoradiotherapy (CCRT) is the current standard treatment; however, the prognosis remains poor. Immunotherapy combined with chemotherapy has demonstrated improved survival outcomes in advanced ESCC. Nevertheless, there is a lack of reports on the role of induction immunotherapy plus chemotherapy prior to CCRT for unresectable locally advanced ESCC. Therefore, this study aimed to evaluate the efficacy and safety of induction immunotherapy plus chemotherapy followed by definitive chemoradiotherapy in patients with unresectable locally advanced ESCC. METHODS: This study retrospectively collected clinical data of patients diagnosed with locally advanced ESCC who were treated with radical CCRT between 2017 and 2021 at our institution. The patients were divided into two groups: an induction immunotherapy plus chemotherapy group (induction IC group) or a CCRT group. To assess progression-free survival (PFS) and overall survival (OS), we employed the Kaplan-Meier method after conducting propensity score matching (PSM). RESULTS: A total of 132 patients with unresectable locally advanced ESCC were included in this study, with 61 (45.26%) patients in the induction IC group and 71 (54.74%) patients in the CCRT group. With a median follow-up of 37.0 months, median PFS and OS were 25.2 and 39.2 months, respectively. The patients in the induction IC group exhibited a significant improvement in PFS and OS in comparison with those in the CCRT group (median PFS: not reached [NR] versus 15.9 months, hazard ratio [HR] 0.526 [95%CI 0.325-0.851], P = 0.0077; median OS: NR versus 25.2 months, HR 0.412 [95%CI 0.236-0.719], P = 0.0012). After PSM (50 pairs), both PFS and OS remained superior in the induction IC group compared to the CCRT group (HR 0.490 [95%CI 0.280-0.858], P = 0.011; HR 0.454 [95%CI 0.246-0.837], P = 0.0093), with 2-year PFS rates of 67.6 and 42.0%, and the 2-year OS rates of 74.6 and 52.0%, respectively. Multivariate analysis revealed that lower tumor stage, concurrent chemotherapy using double agents, and induction immunotherapy plus chemotherapy before CCRT were associated with better prognosis. CONCLUSIONS: Our results showed for the first time that induction immunotherapy plus chemotherapy followed by CCRT for unresectable locally advanced ESCC provided a survival benefit with manageable safety profile. More prospective clinical studies should be warranted.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/terapia , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/patología , Estudios Retrospectivos , Estudios Prospectivos , Puntaje de Propensión , Quimioradioterapia/métodos , Inmunoterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
6.
Small ; : e2405514, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39221645

RESUMEN

Rational construction of high-efficiency photoelectrodes with optimized carrier migration to the ideal active sites, is crucial for enhancing solar water oxidation. However, complexity in precisely modulating interface configuration and directional charge transfer pathways retards the design of robust and stable artificial photosystems. Herein, a straightforward yet effective strategy is developed for compact encapsulation of metal oxides (MOs) with an ultrathin non-conjugated polymer layer to modulate interfacial charge migration and separation. By periodically coating highly ordered TiO2 nanoarrays with oppositely charged polyelectrolyte of poly(dimethyl diallyl ammonium chloride) (PDDA), MOs/polymer composite photoanodes are readily fabricated under ambient conditions. It is verified that electrons photogenerated from the MOs substrate can be efficiently extracted by the ultrathin solid insulating PDDA layer, significantly boosting the carrier transport kinetics and enhancing charge separation of MOs, and thus triggering a remarkable enhancement in the solar water oxidation performance. The origins of the unexpected electron-withdrawing capability of such non-conjugated insulating polymer are unambiguously uncovered, and the scenario occurring at the interface of hybrid photoelectrodes is elucidated. The work would reinforce the fundamental understanding on the origins of generic charge transport capability of insulating polymer and benefit potential wide-spread utilization of insulating polymers as co-catalysts for solar energy conversion.

7.
Mol Carcinog ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136583

RESUMEN

Xenotropic and polytropic retrovirus receptor 1 (XPR1) is the only known transporter associated with Pi efflux in mammals, and its impact on tumor progression is gradually being revealed. However, the role of XPR1 in hepatocellular carcinoma (HCC) is unknown. A bioinformatics screen for the phosphate exporter XPR1 was performed in HCC patients. The expression of XPR1 in clinical specimens was analyzed using quantitative real-time PCR, Western blot analysis, and immunohistochemical assays. Knockdown of the phosphate exporter XPR1 was performed by shRNA transfection to investigate the cellular phenotype and phosphate-related cytotoxicity of the Huh7 and HLF cell lines. In vivo tests were conducted to investigate the tumorigenicity of HCC cells xenografted into immunocompromised mice after silencing XPR1. Compared with that in paracancerous tissue, XPR1 expression in HCC tissues was markedly upregulated. High XPR1 expression significantly correlated with poor patient survival. Silencing of XPR1 leads to decreased proliferation, migration, invasion, and colony formation in HCC cells. Mechanistically, knockdown of XPR1 causes an increase in intracellular phosphate levels; mitochondrial dysfunction characterized by reduced mitochondrial membrane potential and adenosine triphosphate levels; increased reactive oxygen species levels; abnormal mitochondrial morphology; and downregulation of key mitochondrial fusion, fission, and inner membrane genes. This ultimately results in mitochondria-dependent apoptosis. These findings reveal the prognostic value of XPR1 in HCC progression and, more importantly, suggest that XPR1 might be a potential therapeutic target.

8.
Mol Phylogenet Evol ; 193: 108023, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38342159

RESUMEN

The Himalaya-Hengduan Mountains (HHM), a renowned biodiversity hotspot of the world, harbors the most extensive habitats for alpine plants with extraordinary high levels of endemism. Although the general evolution pattern has been elucidated, the underlying processes driving spectacular radiations in many species-rich groups remain elusive. Corydalis DC. is widely distributed throughout the Northern Hemisphere containing more than 500 species, with high diversity in HHM and adjacent regions. Using 95 plastid genes, 3,258,640 nuclear single nucleotide polymorphisms (SNPs) and eight single-copy nuclear genes (SCNs) generated from genome skimming data, we reconstructed a robust time-calibrated phylogeny of Corydalis comprising more than 100 species that represented all subgenera and most sections. Molecular dating indicated that all main clades of Corydalis began to diverge in the Eocene, with the majority of extant species in HHM emerged from a diversification burst after the middle Miocene. Global pattern of mean divergence times indicated that species distributed in HHM were considerably younger than those in other regions, particularly for the two most species-rich clades (V and VI) of Corydalis. The early divergence and the recent diversification of Corydalis were most likely promoted by the continuous orogenesis and climate change associated with the uplift of the Qinghai-Tibetan Plateau (QTP). Our study demonstrates the effectivity of phylogenomic analyses with genome skimming data on the phylogeny of species-rich taxa, and sheds lights on how the uplift of QTP has triggered the evolutionary radiations of large plant genera in HHM and adjacent regions.


Asunto(s)
Corydalis , Filogenia , Himalayas , Biodiversidad , Ecosistema , Plantas
9.
Respir Res ; 25(1): 226, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38811960

RESUMEN

BACKGROUND: This study aimed to explore the incidence of occult lymph node metastasis (OLM) in clinical T1 - 2N0M0 (cT1 - 2N0M0) small cell lung cancer (SCLC) patients and develop machine learning prediction models using preoperative intratumoral and peritumoral contrast-enhanced CT-based radiomic data. METHODS: By conducting a retrospective analysis involving 242 eligible patients from 4 centeres, we determined the incidence of OLM in cT1 - 2N0M0 SCLC patients. For each lesion, two ROIs were defined using the gross tumour volume (GTV) and peritumoral volume 15 mm around the tumour (PTV). By extracting a comprehensive set of 1595 enhanced CT-based radiomic features individually from the GTV and PTV, five models were constucted and we rigorously evaluated the model performance using various metrics, including the area under the curve (AUC), accuracy, sensitivity, specificity, calibration curve, and decision curve analysis (DCA). For enhanced clinical applicability, we formulated a nomogram that integrates clinical parameters and the rad_score (GTV and PTV). RESULTS: The initial investigation revealed a 33.9% OLM positivity rate in cT1 - 2N0M0 SCLC patients. Our combined model, which incorporates three radiomic features from the GTV and PTV, along with two clinical parameters (smoking status and shape), exhibited robust predictive capabilities. With a peak AUC value of 0.772 in the external validation cohort, the model outperformed the alternative models. The nomogram significantly enhanced diagnostic precision for radiologists and added substantial value to the clinical decision-making process for cT1 - 2N0M0 SCLC patients. CONCLUSIONS: The incidence of OLM in SCLC patients surpassed that in non-small cell lung cancer patients. The combined model demonstrated a notable generalization effect, effectively distinguishing between positive and negative OLMs in a noninvasive manner, thereby guiding individualized clinical decisions for patients with cT1 - 2N0M0 SCLC.


Asunto(s)
Neoplasias Pulmonares , Metástasis Linfática , Carcinoma Pulmonar de Células Pequeñas , Tomografía Computarizada por Rayos X , Humanos , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/diagnóstico por imagen , Carcinoma Pulmonar de Células Pequeñas/diagnóstico por imagen , Carcinoma Pulmonar de Células Pequeñas/epidemiología , Carcinoma Pulmonar de Células Pequeñas/patología , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Metástasis Linfática/diagnóstico por imagen , Incidencia , Tomografía Computarizada por Rayos X/métodos , Valor Predictivo de las Pruebas , Medios de Contraste , Estadificación de Neoplasias/métodos , Adulto , Ganglios Linfáticos/patología , Ganglios Linfáticos/diagnóstico por imagen , Anciano de 80 o más Años , Radiómica
10.
Artículo en Inglés | MEDLINE | ID: mdl-38530339

RESUMEN

The baijiu fermentation environment hosts a variety of micro-organisms, some of which still remain uncultured and uncharacterized. In this study, the isolation, cultivation and characterization of three novel aerobic bacterial strains are described. The cells of strain REN20T were Gram-negative, strictly aerobic, motile and grew at 26-37 °C, at pH 6.0-9.0 and in the presence of 0-5.0   % (w/v) NaCl. The cells of strain REN29T were Gram-negative, strictly aerobic, motile and grew at 15-30 °C, at pH 6.0-9.0 and in the presence of 0-10.0   % (w/v) NaCl. The cells of strain REN33T were Gram-positive, strictly aerobic, motile and grew at 15-37 °C, at pH 5.0-10.0 and in the presence of 0-7.0   % (w/v) NaCl. The digital DNA-DNA hybridization and average nucleotide identity by orthology values between type strains in related genera and REN20T (20.3-36.8 % and 79.8-89.9  %), REN29T (20.3-36.8  % and 74.5-88.5  %) and REN33T (22.6-48.6  % and 75.8-84.2  %) were below the standard cut-off criteria for the delineation of bacterial species, respectively. Based on polyphasic taxonomy analysis, we propose three new species, Bosea beijingensis sp. nov. (=REN20T=GDMCC 1.2894T=JCM 35118T), Telluria beijingensis sp. nov. (=REN29T=GDMCC 1.2896T=JCM 35119T) and Agrococcus beijingensis sp. nov. (=REN33T=GDMCC 1.2898T=JCM 35164T), which were recovered during cultivation and isolation from baijiu mash.


Asunto(s)
Actinomycetales , Bradyrhizobiaceae , Oxalobacteraceae , Cloruro de Sodio , Filogenia , Análisis de Secuencia de ADN , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Composición de Base , Ácidos Grasos/química , Bacterias Aerobias
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