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1.
Nature ; 600(7888): 279-284, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34837071

RESUMEN

Confocal microscopy1 remains a major workhorse in biomedical optical microscopy owing to its reliability and flexibility in imaging various samples, but suffers from substantial point spread function anisotropy, diffraction-limited resolution, depth-dependent degradation in scattering samples and volumetric bleaching2. Here we address these problems, enhancing confocal microscopy performance from the sub-micrometre to millimetre spatial scale and the millisecond to hour temporal scale, improving both lateral and axial resolution more than twofold while simultaneously reducing phototoxicity. We achieve these gains using an integrated, four-pronged approach: (1) developing compact line scanners that enable sensitive, rapid, diffraction-limited imaging over large areas; (2) combining line-scanning with multiview imaging, developing reconstruction algorithms that improve resolution isotropy and recover signal otherwise lost to scattering; (3) adapting techniques from structured illumination microscopy, achieving super-resolution imaging in densely labelled, thick samples; (4) synergizing deep learning with these advances, further improving imaging speed, resolution and duration. We demonstrate these capabilities on more than 20 distinct fixed and live samples, including protein distributions in single cells; nuclei and developing neurons in Caenorhabditis elegans embryos, larvae and adults; myoblasts in imaginal disks of Drosophila wings; and mouse renal, oesophageal, cardiac and brain tissues.


Asunto(s)
Aprendizaje Profundo , Microscopía Confocal/métodos , Microscopía Confocal/normas , Animales , Caenorhabditis elegans/citología , Caenorhabditis elegans/embriología , Caenorhabditis elegans/crecimiento & desarrollo , Línea Celular Tumoral , Drosophila melanogaster/citología , Drosophila melanogaster/crecimiento & desarrollo , Humanos , Discos Imaginales/citología , Ratones , Mioblastos/citología , Especificidad de Órganos , Análisis de la Célula Individual , Fijación del Tejido
2.
Circ Res ; 135(1): 26-40, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38747181

RESUMEN

BACKGROUND: Calcium (Ca2+) uptake by mitochondria occurs via the mitochondrial Ca2+ uniporter. Mitochondrial Ca2+ uniporter exists as a complex, regulated by 3 MICU (mitochondrial Ca2+ uptake) proteins localized in the intermembrane space: MICU1, MICU2, and MICU3. Although MICU3 is present in the heart, its role is largely unknown. METHODS: We used CRISPR-Cas9 to generate a mouse with global deletion of MICU3 and an adeno-associated virus (AAV9) to overexpress MICU3 in wild-type mice. We examined the role of MICU3 in regulating mitochondrial calcium ([Ca2+]m) in ex vivo hearts using an optical method following adrenergic stimulation in perfused hearts loaded with a Ca2+-sensitive fluorophore. Additionally, we studied how deletion and overexpression of MICU3, respectively, impact cardiac function in vivo by echocardiography and the molecular composition of the mitochondrial Ca2+ uniporter complex via Western blot, immunoprecipitation, and Blue native-PAGE analysis. Finally, we measured MICU3 expression in failing human hearts. RESULTS: MICU3 knock out hearts and cardiomyocytes exhibited a significantly smaller increase in [Ca2+]m than wild-type hearts following acute isoproterenol infusion. In contrast, heart with overexpression of MICU3 exhibited an enhanced increase in [Ca2+]m compared with control hearts. Echocardiography analysis showed no significant difference in cardiac function in knock out MICU3 mice relative to wild-type mice at baseline. However, mice with overexpression of MICU3 exhibited significantly reduced ejection fraction and fractional shortening compared with control mice. We observed a significant increase in the ratio of heart weight to tibia length in hearts with overexpression of MICU3 compared with controls, consistent with hypertrophy. We also found a significant decrease in MICU3 protein and expression in failing human hearts. CONCLUSIONS: Our results indicate that increased and decreased expression of MICU3 enhances and reduces, respectively, the uptake of [Ca2+]m in the heart. We conclude that MICU3 plays an important role in regulating [Ca2+]m physiologically, and overexpression of MICU3 is sufficient to induce cardiac hypertrophy, making MICU3 a possible therapeutic target.


Asunto(s)
Proteínas de Unión al Calcio , Calcio , Ratones Noqueados , Mitocondrias Cardíacas , Proteínas de Transporte de Membrana Mitocondrial , Miocitos Cardíacos , Animales , Femenino , Humanos , Masculino , Ratones , Calcio/metabolismo , Canales de Calcio/metabolismo , Canales de Calcio/genética , Señalización del Calcio , Proteínas de Unión al Calcio/metabolismo , Proteínas de Unión al Calcio/genética , Cardiomegalia/metabolismo , Cardiomegalia/genética , Proteínas de Transporte de Catión/metabolismo , Proteínas de Transporte de Catión/genética , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/genética , Ratones Endogámicos C57BL , Mitocondrias Cardíacas/metabolismo , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Proteínas de Transporte de Membrana Mitocondrial/genética , Miocitos Cardíacos/metabolismo
3.
Hepatology ; 79(1): 118-134, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37594323

RESUMEN

BACKGROUND AND AIM: Baveno VII workshop recommends the use of preemptive TIPS (p-TIPS) in patients with cirrhosis and acute variceal bleeding (AVB) at high- risk of treatment failure. However, the criteria defining "high-risk" have low clinical accessibility or include subjective variables. We aimed to develop and externally validate a model for better identification of p-TIPS candidates. APPROACH AND RESULTS: The derivation cohort included 1554 patients with cirrhosis and AVB who were treated with endoscopy plus drug (n = 1264) or p-TIPS (n = 290) from 12 hospitals in China between 2010 and 2017. We first used competing risk regression to develop a score for predicting 6-week and 1-year mortality in patients treated with endoscopy plus drugs, which included age, albumin, bilirubin, international normalized ratio, white blood cell, creatinine, and sodium. The score was internally validated with the bootstrap method, which showed good discrimination (6 wk/1 y concordance-index: 0.766/0.740) and calibration, and outperformed other currently available models. In the second stage, the developed score was combined with treatment and their interaction term to predicate the treatment effect of p-TIPS (mortality risk difference between treatment groups) in the whole derivation cohort. The estimated treatment effect of p-TIPS varied substantially among patients. The prediction model had good discriminative ability (6 wk/1 y c -for-benefit: 0.696/0.665) and was well calibrated. These results were confirmed in the validation dataset of 445 patients with cirrhosis with AVB from 6 hospitals in China between 2017 and 2019 (6-wk/1-y c-for-benefit: 0.675/0.672). CONCLUSIONS: We developed and validated a clinical prediction model that can help to identify individuals who will benefit from p-TIPS, which may guide clinical decision-making.


Asunto(s)
Várices Esofágicas y Gástricas , Derivación Portosistémica Intrahepática Transyugular , Humanos , Várices Esofágicas y Gástricas/etiología , Pronóstico , Modelos Estadísticos , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/prevención & control , Cirrosis Hepática/etiología , Derivación Portosistémica Intrahepática Transyugular/efectos adversos
4.
Nano Lett ; 24(13): 3866-3873, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38442405

RESUMEN

The low wear resistance of macroscale graphene coatings does not match the ultrahigh mechanical strength and chemical inertness of the graphene layer itself; however, the wear mechanism responsible for this issue at low mechanical stress is still unclear. Here, we demonstrate that the susceptibility of the graphene monolayer to wear at its atomic step edges is governed by the mechanochemistry of frictional interfaces. The mechanochemical reactions activated by chemically active SiO2 microspheres result in atomic attrition rather than mechanical damage such as surface fracture and folding by chemically inert diamond tools. Correspondingly, the threshold contact stress for graphene edge wear decreases more than 30 times to the MPa level, and mechanochemical wear can be described well with the mechanically assisted Arrhenius-type kinetic model, i.e., exponential dependence of the removal rate on the contact stress. These findings provide a strategy for improving the antiwear of graphene-based materials by reducing the mechanochemical interactions at tribological interfaces.

5.
Nano Lett ; 24(23): 6858-6864, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38808664

RESUMEN

Mechanochemical strategies are widely used in various fields, ranging from friction and wear to mechanosynthesis, yet how the mechanical stress activates the chemical reactions at the electronic level is still open. We used first-principles density functional theory to study the rule of the stress-modified electronic states in transmitting mechanical energy to trigger chemical responses for different mechanochemical systems. The electron density redistribution among initial, transition, and final configurations is defined to correlate the energy evolution during reactions. We found that stress-induced changes in electron density redistribution are linearly related to activation energy and reaction energy, indicating the transition from mechanical work to chemical reactivity. The correlation coefficient is defined as the term "interface reactivity coefficient" to evaluate the susceptibility of chemical reactivity to mechanical action for material interfaces. The study may shed light on the electronic mechanism of the mechanochemical reactions behind the fundamental model as well as the mechanochemical phenomena.

6.
Apoptosis ; 29(1-2): 103-120, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37875647

RESUMEN

Disulfidoptosis and ferroptosis are two distinct programmed cell death pathways that have garnered considerable attention due to their potential as therapeutic targets. However, despite their significance of these pathways, the role of disulfidoptosis-related ferroptosis genes in hepatocellular carcinoma (HCC) remains unclear. In this study, we employed a comprehensive approach that utilized various sophisticated techniques such as Pearson analysis, differential analysis, uniCox regression, lasso, ranger, and multivariable Cox regression to develop the disulfidoptosis-related ferroptosis (DRF) score. We then classified patients with HCC into high- and low-score groups to examine the association between the DRF score and various outcomes, including prognosis, functional enrichment, immune infiltration, immunotherapy, TACE sensitivity, drug sensitivity, and single-cell level function. Finally, we conducted in vitro experiments to validate the function of KIF20A. Our analysis revealed that KIF20A, G6PD, SLC7A11, and SLC2A1 were integral to constructing the DRF score. Our findings showed that patients with low DRF scores had significantly better prognoses and were more responsive to immunotherapy, TACE, and chemotherapy than those with high DRF scores. Based on our results obtained from bulk RNA-seq, single-cell RNA-seq, and in vitro experiments, we identified the cell cycle pathway as the primary distinguished factor between high-score and low-score groups. This study sheds light on the contribution of disulfidoptosis-related ferroptosis genes to the development and progression of HCC. The information gleaned from this study can be leveraged to improve our understanding of their potential as therapeutic targets for HCC treatment.


Asunto(s)
Carcinoma Hepatocelular , Ferroptosis , Neoplasias Hepáticas , Humanos , Apoptosis , Carcinoma Hepatocelular/genética , Ferroptosis/genética , Neoplasias Hepáticas/genética , Aprendizaje Automático
7.
Biochem Biophys Res Commun ; 709: 149809, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38552555

RESUMEN

Hyperuricemia is a chronic metabolic disease caused by purine metabolism disorder. And several gene loci and transporter proteins that associated with uric acid transport functions have been identified. Retinol Dehydrogenase 12 (RDH12), recognized for its role in safeguarding photoreceptors, and our study investigated the potential impact of Rdh12 mutations on other organs and diseases, particularly hyperuricemia. We assessed Rdh12 mRNA expression levels in various tissues and conducted serum biochemical analyses in Rdh12-/- mice. Compared with the wild type, significant alterations in serum uric acid levels and kidney-related biochemical indicators have been revealed. Then further analysis, including quantitative RT-PCR of gene expression in the liver and kidney, highlighted variations in the expression levels of specific genes linked to hyperuricemia. And renal histology assessment exposed mild pathological lesions in the kidneys of Rdh12-/- mice. In summary, our study suggests that Rdh12 mutations impact not only retinal function but also contribute to hyperuricemia and renal disease phenotypes in mice. Our finding implies that individuals with Rdh12 mutations may be prone to hyperuricemia and gout, emphasizing the significance of preventive measures and regular examinations in daily life.


Asunto(s)
Hiperuricemia , Ratones , Animales , Hiperuricemia/genética , Ácido Úrico , Oxidorreductasas de Alcohol/genética , Oxidorreductasas de Alcohol/metabolismo , Fenotipo
8.
Cancer Cell Int ; 24(1): 173, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760774

RESUMEN

BACKGROUND: Drug resistance poses a significant challenge in cancer treatment, particularly as a leading cause of therapy failure. Cisplatin, the primary drug for lung adenocarcinoma (LUAD) chemotherapy, shows effective treatment outcomes. However, the development of resistance against cisplatin is a major obstacle. Therefore, identifying genes resistant to cisplatin and adopting personalized treatment could significantly improve patient outcomes. METHODS: By examining transcriptome data of cisplatin-resistant LUAD cells from the GEO database, 181 genes associated with cisplatin resistance were identified. Using univariate regression analysis, random forest and multivariate regression analyses, two prognostic genes, E2F7 and FAM83A, were identified. This study developed a prognostic model utilizing E2F7 and FAM83A as key indicators. The Cell Counting Kit 8 assay, Transwell assay, and flow cytometry were used to detect the effects of E2F7 on the proliferation, migration, invasiveness and apoptosis of A549/PC9 cells. Western blotting was used to determine the effect of E2F7 on AKT/mTOR signaling pathway. RESULTS: This study has pinpointed two crucial genes associated with cisplatin resistance, E2F7 and FAM83A, and developed a comprehensive model to assist in the diagnosis, prognosis, and evaluation of relapse risk in LUAD. Analysis revealed that patients at higher risk, according to these genetic markers, had elevated levels of immune checkpoints (PD-L1 and PD-L2). The prognostic and diagnosis values of E2F7 and FAM83A were further confirmed in clinical data. Furthermore, inhibiting E2F7 in lung cancer cells markedly reduced their proliferation, migration, invasion, and increased apoptosis. In vivo experiments corroborated these findings, showing reduced tumor growth and lung metastasis upon E2F7 suppression in lung cancer models. CONCLUSION: Our study affirms the prognostic value of a model based on two DEGs, offering a reliable method for predicting the success of tumor immunotherapy in patients with LUAD. The diagnostic and predictive model based on these genes demonstrates excellent performance. In vitro, reducing E2F7 levels shows antitumor effects by blocking LUAD growth and progression. Further investigation into the molecular mechanisms has highlighted E2F7's effect on the AKT/mTOR signaling pathway, underscoring its therapeutic potential. In the era of personalized medicine, this DEG-based model promises to guide clinical practice.

9.
Intern Med J ; 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38465389

RESUMEN

BACKGROUND: Famine exposure in childhood is proven to be associated with multiple chornic disease in adult but has not been studied with chronic kidney disease (CKD). AIMS: This study was conducted to identify the relationship between famine exposure during infancy and childhood - specifically, the Chinese famine of 1959-1961 - and the risk of adult-onset chronic kidney disease (CKD) among Chinese individuals. METHODS: This study included 2937 individuals from the Qingdao Diabetes Prevention Program. They were stratified by birth year into infancy-exposed (1956-1958), childhood-exposed (1950-1955) and unexposed (1963-1971) groups. The estimated glomerular filtration rate (eGFR) was calculated using the Chronic Kidney Disease Epidemiology Collaboration equation. CKD was defined as an eGFR of <90 mL/min/1.73 m2 . RESULTS: The mean eGFR values for the infancy-exposed and childhood-exposed groups were 107.23 ± 12.53 and 103.23 ± 12.44 mL/min/1.73 m2 , respectively, both of which were lower than that of the unexposed group (114.82 ± 13.39 mL/min/1.73 m2 ; P < 0.05). In the crude model, the odds ratio (OR) for CKD was 2.00 (95% confidence interval (CI): 1.39-2.88) in the infancy-exposed group and 2.92 (95% CI: 2.17-3.93) in the childhood-exposed group. Further adjustments for urban/rural residence, body mass index, age, current smoking, type 2 diabetes, systolic blood pressure, diastolic blood pressure and total cholesterol did not significantly alter the association between famine exposure and CKD. The corresponding ORs were 1.71 (95% CI: 1.17-2.50) and 2.48 (95% CI: 1.81-3.40) for the infancy-exposed and childhood-exposed groups respectively. CONCLUSIONS: Famine exposure during infancy and childhood is associated with a long-term decline in eGFR and an increased adult-onset CKD risk. Early intervention for high-risk individuals may mitigate the risk of adult-onset CKD.

10.
Nano Lett ; 23(19): 8842-8849, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37729549

RESUMEN

Wear of sliding contacts causes device failure and energy costs; however, the microscopic principle in activating wear of the interfaces under stress is still open. Here, the typical nanoscale wear, in the case of silicon against silicon dioxide, is investigated by single-asperity wear experiments and density functional theory calculations. The tests demonstrate that the wear rate of silicon in ambient air increases exponentially with stress and does not obey classical Archard's law. Series calculations of atomistic wear reactions generally reveal that the mechanical stress linearly drives the electron transfer to activate the sequential formation and rupture of interfacial bonds in the atomistic wear process. The atomistic wear model is thus resolved by combining the present stress-driven electron transfer model with Maxwell-Boltzmann statistics. This work may advance electronic insights into the law of nanoscale wear for understanding and controlling wear and manufacturing of material surfaces.

11.
J Am Chem Soc ; 145(9): 5536-5544, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36811399

RESUMEN

It is well-known that the electron nature of a solid in contact plays a predominant role in determining the many properties of the contact systems, but the general rules of electron coupling that govern interfacial friction remain an open issue for the surface/interface community. Here, density functional theory calculations were used to investigate the physical origins of friction of solid interfaces. It was found that interfacial friction can be inherently traced back to the electronic barrier to the change in the contact configuration of the joints in slip due to the resistance of energy level rearrangement leading to electron transfer, which applies for various interface types ranging from van der Waals, metallic, and ionic to covalent joints. The variation of the electron density accompanying contact conformation changes along the sliding pathways is defined to track the frictional energy dissipation process occurring in slip. The results demonstrate that the frictional energy landscapes evolve synchronously with responding charge density evolution along sliding pathways, yielding an explicitly linear dependence of frictional dissipation on electronic evolution. The correlation coefficient enables us to interpret the fundamental concept of shear strength. The present charge evolution model thereby provides insights into the classic hypothesis that the friction force scales with the real contact area. This may shed light on the intrinsic origin of friction at the electronic level, opening the way to the rational design of nanomechanical devices as well as the understanding of the natural faults.

12.
Mol Carcinog ; 62(9): 1355-1368, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37212487

RESUMEN

The global burden of hepatocellular carcinoma (HCC) as a preeminent etiology of cancer-related mortalities sheds light on the imperative necessity for a more profound comprehension of its fundamental biological mechanisms. In this context, the precise function of the 26S proteasome non-ATPase regulatory subunit 11 (PSMD11) in HCC remains equivocal. To address this vital knowledge gap, we interrogated the cancer genome atlas, genotype-tissue expression, International cancer genome consortium, gene expression omnibus, the cancer cell line encyclopedia, and tumor immune single-cell hub databases to evaluate the expression pattern of PSMD11, further confirmed by reverse-transcription quantitative polymerase chain reaction (RT-qPCR) in LO2, MHCC-97H, HepG2, and SMMC7721 cell lines. Additionally, we meticulously assessed the clinical significance and prognostic value of PSMD11, while also exploring its potential molecular mechanisms in HCC. Our findings demonstrated that PSMD11 was highly expressed in HCC tissues, correlating with pathologic stage and histologic grade, thereby conferring a poor prognosis. Mechanistically, PSMD11 appears to exert its tumorigenic effects through the modulation of tumor metabolism-related pathways. Impressively, low PSMD11 expression was associated with increased immune effector cell infiltration, heightened responsiveness to molecular targeted drugs such as dasatinib, erlotinib, gefitinib, and imatinib, as well as reduced somatic mutation rate. Additionally, we demonstrated that PSMD11 might modulate HCC development through intricate interactions with cuproptosis-related genes ATP7A, DLAT, and PDHA1. Our comprehensive analyses collectively suggest that PSMD11 represents a promising therapeutic target in HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Pronóstico , Complejo de la Endopetidasa Proteasomal
13.
Eur Radiol ; 33(12): 8669-8681, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37368105

RESUMEN

OBJECTIVES: This study aimed to investigate the efficacy and safety of transarterial chemoembolization (TACE) plus camrelizumab, a monoclonal antibody targeting programmed death-1, and apatinib for patients with intermediate and advanced hepatocellular carcinoma (HCC) in a real-world setting. METHODS: A total of 586 HCC patients treated with either TACE plus camrelizumab and apatinib (combination group, n = 107) or TACE monotherapy (monotherapy group, n = 479) were included retrospectively. Propensity score matching analysis was used to match patients. The overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and safety in the combination group were described in comparison to monotherapy. RESULTS: After propensity score matching (1:2), 84 patients in the combination group were matched to 147 patients in the monotherapy group. The median age was 57 years and 71/84 (84.5%) patients were male in the combination group, while the median age was 57 years with 127/147 (86.4%) male in the monotherapy group. The median OS, PFS, and ORR in the combination group were significantly higher than those in the monotherapy group (median OS, 24.1 vs. 15.7 months, p = 0.008; median PFS, 13.5 vs. 7.7 months, p = 0.003; ORR, 59.5% [50/84] vs. 37.4% [55/147], p = 0.002). On multivariable Cox regression, combination therapy was associated with significantly better OS (adjusted hazard ratio [HR], 0.41; 95% confidence interval [CI], 0.26-0.64; p < 0.001) and PFS (adjusted HR, 0.52; 95% CI, 0.37-0.74; p < 0.001). Grade 3 or 4 adverse events occurred in 14/84 (16.7%) and 12/147 (8.2%) in the combination and monotherapy groups, respectively. CONCLUSIONS: TACE plus camrelizumab and apatinib showed significantly better OS, PFS, and ORR versus TACE monotherapy for predominantly advanced HCC. CLINICAL RELEVANCE STATEMENT: Compared with TACE monotherapy, TACE plus immunotherapy and molecular targeted therapy showed better clinical efficacy for predominantly advanced HCC patients, with a higher incidence of adverse events. KEY POINTS: • This propensity score-matched study demonstrates that TACE plus immunotherapy and molecular targeted therapy have a longer OS, PFS, and ORR compared with TACE monotherapy in HCC. • Grade 3 or 4 adverse events occurred in 14/84 (16.7%) patients treated with TACE plus immunotherapy and molecular targeted therapy compared with 12/147 (8.2%) patients in the monotherapy group, while no grade 5 adverse events were observed in all cohorts.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Humanos , Masculino , Persona de Mediana Edad , Femenino , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Antineoplásicos/uso terapéutico , Quimioembolización Terapéutica/efectos adversos , Puntaje de Propensión , Estudios Retrospectivos
14.
J Nanobiotechnology ; 21(1): 221, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37438800

RESUMEN

Breast cancer bone metastasis has become a common cancer type that still lacks an effective treatment method. Although epigenetic drugs have demonstrated promise in cancer therapy, their nontargeted accumulation and drug resistance remain nonnegligible limiting factors. Herein, we first found that icaritin had a strong synergistic effect with an epigenetic drug (JQ1) in the suppression of breast cancer, which could help to relieve drug resistance to JQ1. To improve tumor-targeted efficacy, we developed a hypoxia-cleavable, RGD peptide-modified poly(D,L-lactide-co-glycolide) (PLGA) nanoparticle (termed ARNP) for the targeted delivery of JQ1 and icaritin. The decoration of long cleavable PEG chains can shield RGD peptides during blood circulation and reduce cellular uptake at nonspecific sites. ARNP actively targets breast cancer cells via an RGD-αvß3 integrin interaction after PEG chain cleavage by responding to hypoxic tumor microenvironment. In vitro and in vivo assays revealed that ARNP exhibited good biodistribution and effectively suppressed primary tumor and bone metastasis. Meanwhile, ARNP could alleviate bone erosion to a certain extent. Furthermore, ARNP significantly inhibited pulmonary metastasis secondary to bone metastasis. The present study suggests that ARNP has great promise in the treatment of breast cancer and bone metastasis due to its simple and practical potential.


Asunto(s)
Neoplasias Óseas , Nanomedicina , Humanos , Preparaciones Farmacéuticas , Distribución Tisular , Neoplasias Óseas/tratamiento farmacológico , Epigénesis Genética , Microambiente Tumoral
15.
Nano Lett ; 22(14): 6018-6025, 2022 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-35695465

RESUMEN

Atomically thin two-dimensional (2D) materials are excellent candidates for utilization as a solid lubricant or additive at all length scales from macro-scale mechanical devices to micro/nano-electromechanical systems (MEMS/NEMS). In such applications, wear resistance of ultrathin 2D materials is critical for sustained lubrication performance. Here, we investigated the wear of fluorinated graphene (FG) nanosheets deposited on silicon surfaces using atomic force microscopy (AFM) and discovered that the wear resistance of FG improves as the FG thickness decreases from 4.2 to 0.8 nm (corresponding to seven layers to single layer) and the surface energy of the substrate underneath the FG nanosheets increases. On the basis of density function theory (DFT) calculations, the negative correlation of wear resistance to FG thickness and the positive correlation to substrate surface energy could be explained with the degree of interfacial charge transfer between FG and substrate which affects the strength of FG adhesion to the substrate.

16.
Nano Lett ; 22(11): 4410-4420, 2022 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-35575719

RESUMEN

Tumor-associated macrophages (TAMs) are a promising therapeutic target for cancers, but achieving multitarget therapy of TAMs is still challenging. Here, we develop a protein-crowned micelle system for targeted and synergistic TAM reprogramming to enhance cancer treatment. The doxorubicin-loaded micelles with a hemoglobin crown (Hb-DOXM) can bind with endogenous plasma haptoglobin to realize specific M2-type TAM targeting. Under the tumor hypoxic and acidic environments, Hb-DOXM can responsively release O2 and DOX to reduce the recruitment of TAMs by hypoxia remission and release DOX to kill M2-type TAMs and cancer cells. To reprogram TAMs adequately, the TAM-modulating drug celecoxib is further encapsulated (Hb-DOXM@Cel) to repolarize M2-type TAMs. The targeted and synergistic TAM reprogramming by Hb-DOXM@Cel can remodel the tumor microenvironment (TME) to an immunostimulatory microenvironment and augment the antitumor effect of cytotoxic T lymphocyte, thus strongly enhancing the DOX-based chemotherapy. The protein-crowned micelle strategy presents a targeted and synergistic TAM therapy tool for enhanced cancer treatment.


Asunto(s)
Neoplasias , Macrófagos Asociados a Tumores , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Humanos , Inmunoterapia , Micelas , Neoplasias/tratamiento farmacológico , Microambiente Tumoral
17.
Hepatology ; 73(4): 1478-1493, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32706906

RESUMEN

BACKGROUND AND AIMS: Optimal candidates for early transjugular intrahepatic portosystemic shunt (TIPS) in patients with Child-Pugh B cirrhosis and acute variceal bleeding (AVB) remain unclear. This study aimed to test the hypothesis that risk stratification using the Chronic Liver Failure Consortium Acute Decompensation score (CLIF-C ADs) may be useful to identify a subgroup at high risk of mortality or further bleeding that may benefit from early TIPS in patients with Child-Pugh B cirrhosis and AVB. APPROACH AND RESULTS: We analyzed the pooled individual data from two previous studies of 608 patients with Child-Pugh B cirrhosis and AVB who received standard treatment between 2010 and 2017 in China. The concordance index values of CLIF-C ADs for 6-week and 1-year mortality (0.715 and 0.708) were significantly better than those of active bleeding at endoscopy (0.633 [P < 0.001] and 0.556 [P < 0.001]) and other prognostic models. With X-tile software identifying an optimal cutoff value, patients were categorized as low risk (CLIF-C ADs <48), intermediate risk (CLIF-C ADs 48-56), and high risk (CLIF-C ADs >56), with a 5.6%, 16.8%, and 25.4% risk of 6-week death, respectively. Nevertheless, the performance of CLIF-C ADs for predicting a composite endpoint of 6-week death or further bleeding was not satisfactory (area under the receiver operating characteristics curve [AUC], 0.588). A nomogram incorporating components of CLIF-C ADs and albumin, platelet, active bleeding, and ascites significantly improved the prediction accuracy (AUC, 0.725). CONCLUSIONS: In patients with Child-Pugh B cirrhosis and AVB, risk stratification using CLIF-C ADs identifies a subgroup with high risk of death that may derive survival benefit from early TIPS. With improved prediction accuracy for 6-week death or further bleeding, the data-driven nomogram may help to stratify patients in randomized trials. Future external validation of these findings in patients with different etiologies is required.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada , Várices Esofágicas y Gástricas/epidemiología , Várices Esofágicas y Gástricas/cirugía , Hemorragia Gastrointestinal/epidemiología , Hemorragia Gastrointestinal/cirugía , Cirrosis Hepática/epidemiología , Derivación Portosistémica Intrahepática Transyugular/métodos , Proyectos de Investigación , Enfermedad Aguda/epidemiología , Adulto , Anciano , China/epidemiología , Comorbilidad , Várices Esofágicas y Gástricas/mortalidad , Femenino , Estudios de Seguimiento , Hemorragia Gastrointestinal/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Nomogramas , Pronóstico , Estudios Prospectivos , Estudios Retrospectivos , Medición de Riesgo , Resultado del Tratamiento
18.
Langmuir ; 38(38): 11699-11706, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36109854

RESUMEN

The definition of atomic-scale contact is a very ambiguous issue owing to the discrete atomic arrangement, which hinders the development of contact theory and nano-tribological techniques. In this work, we studied the atomic-scale contact area and their correlations with friction force based on three distinct contact definitions (interatomic distance, force, and interfacial chemical bonds) by performing large-scale atomistic simulations on a typical ball-on-disk contact model. In the simulations, the measured contact areas defined by interatomic distance, force, and interfacial chemical bonds (referred as to Adist, Aforce, and Abond, respectively) are not equivalent at all, while we interestingly clarify that only Adist is consistent with the one calculated by continuum Hertz contact mechanics, and moreover, only Abond is proportional to the friction force indicating that Abond is the dominant one for determining materials' frictional behaviors. The above fundamental insights into the atomic-scale contact problems are useful to deeply understand the origins of tribological phenomena and contribute to the further prediction of atomic-scale friction.

19.
Eur Radiol ; 32(9): 5799-5810, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35381853

RESUMEN

OBJECTIVES: Objective response rate (ORR) under mRECIST criteria after transarterial chemoembolization (TACE) is a well-perceived surrogate endpoint of overall survival (OS). However, its optimal time point remains controversial and may be influenced by tumor burden. We aim to investigate the surrogacy of initial/best ORR in relation to tumor burden. METHODS: A total of 1549 eligible treatment-naïve patients with unresectable hepatocellular carcinoma (HCC), Child-Pugh score ≤ 7, and performance status score ≤ 1 undergoing TACE between January 2010 and May 2016 from 17 academic hospitals were retrospectively analyzed. Based on "six-and-twelve" criteria, tumor burden was graded as low, intermediate, and high if the sum of the maximum tumor diameter and tumor number was ≤ 6, > 6 but ≤ 12, and > 12, respectively. RESULTS: Both initial and best ORRs interacted with tumor burden. Initial and best ORRs could equivalently predict and correlate with OS in low (adjusted HR, 2.55 and 2.95, respectively, both p < 0.001; R = 0.84, p = 0.035, and R = 0.97, p = 0.002, respectively) and intermediate strata (adjusted HR, 1.81 and 2.22, respectively, both p < 0.001; R = 0.74, p = 0.023, and R = 0.9, p = 0.002, respectively). For high strata, only best ORR exhibited qualified surrogacy (adjusted HR, 2.61, p < 0.001; R = 0.70, p = 0.035), whereas initial ORR was not significant (adjusted HR, 1.08, p = 0.357; R = 0.22, p = 0.54). CONCLUSIONS: ORR as surrogacy of OS is associated with tumor burden. For patients with low/intermediate tumor burden, initial ORR should be preferred in its early availability upon similar sensitivity, whereas for patients with high tumor burden, best ORR has optimal sensitivity. Timing of OR assessment should be tailored according to tumor burden. KEY POINTS: • This is the first study utilizing individual patient data to comprehensively analyze the surrogacy of ORR with a long follow-up period. • Optimal timing of ORR assessment for predicting survival should be tailored according to tumor burden. • For patients with low and intermediate tumor burden, initial ORR is optimal for its timeliness upon similar sensitivity with best ORR. For patients with high tumor burden, best ORR has optimal sensitivity.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/patología , Humanos , Neoplasias Hepáticas/patología , Estudios Retrospectivos , Carga Tumoral
20.
Int J Mol Sci ; 23(9)2022 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-35563098

RESUMEN

Liver cancer is one of the most prevalent cancers in humans. Hepatocytes normally undergo dedifferentiation after the onset of hepatocellular carcinoma, which in turn facilitates the progression of cancer. Although the process of hepatocellular carcinoma dedifferentiation is of significant research and clinical value, the cellular and molecular mechanisms underlying it are still not fully characterized. We constructed a zebrafish liver cancer model based on overexpression of the oncogene krasG12V to investigate the hepatocyte dedifferentiation in hepatocellular carcinoma. We found that, after hepatocarcinogenesis, hepatocytes dedifferentiated and the Notch signaling pathway was upregulated in this progress. Furthermore, we found that inhibition of the Notch signaling pathway or deficiency of sox9b both prevented hepatocyte dedifferentiation following hepatocellular carcinoma induction, reducing cancer metastasis and improving survival. In conclusion, we found that hepatocytes undergo dedifferentiation after hepatocarcinogenesis, a process that requires Notch signaling and likewise the activation of Sox9.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Carcinogénesis/metabolismo , Carcinoma Hepatocelular/metabolismo , Hepatocitos/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo
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