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1.
BMJ Open ; 14(5): e083228, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38772899

RESUMEN

INTRODUCTION: Patients with liver cancer are susceptible to experiencing a decline in muscle mass and function, which can lead to physical frailty and have a negative impact on prognosis. However, there is currently a lack of physical activity interventions specifically tailored for these patients. Therefore, we have developed a modular multimodal hospital-home chain physical activity rehabilitation programme (3M2H-PARP) designed specifically for patients with liver cancer undergoing transarterial chemoembolisation (TACE). We aim to validate the effectiveness and feasibility of this programme through a randomised controlled trial (RCT). METHODS AND ANALYSIS: 3M2H-PARP RCT will compare a 12-week, modular, multimodal physical activity rehabilitation programme that includes supervised exercise in a hospital setting and self-management exercise at home. The programmes consist of aerobic, resistance, flexibility and balance exercise modules, and standard survivorship care in a cohort of liver cancer survivors who have undergone TACE. The control group will receive standard care. A total of 152 participants will be randomly assigned to either the 3M2H-PARP group or the control group. Assessments will be conducted at three time points: baseline, after completing the intervention and a 24-week follow-up visit. The following variables will be evaluated: liver frailty index, Functional Assessment of Cancer Therapy-Hepatobiliary subscale, Cancer Fatigue Scale, Pittsburgh Sleep Quality Index, Hospital Anxiety and Depression Scale and physical activity level. After the completion of the training programme, semi-structured interviews will be conducted with participants from the 3M2H-PARP group to investigate the programme's impact on their overall well-being. SPSS V.26.0 software will be used for statistical analyses. ETHICS AND DISSEMINATION: Ethical approval has been granted by the Jiangnan University School of Medicine Research Ethics Committee. The findings will be disseminated through publication in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: ChiCTR2300076800.


Asunto(s)
Terapia por Ejercicio , Neoplasias Hepáticas , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Terapia por Ejercicio/métodos , Neoplasias Hepáticas/rehabilitación , Calidad de Vida , Quimioembolización Terapéutica/métodos , Femenino , Ejercicio Físico , Masculino
2.
ACS Appl Mater Interfaces ; 16(11): 13729-13744, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38457643

RESUMEN

Current electrocatalysts for oxygen evolution reaction (OER) are either expensive (such as IrO2, RuO2) or/and exhibit high overpotential as well as sluggish kinetics. This article reports mesoporous earth-abundant iron (Fe)-nitrogen (N) doped carbon electrocatalysts with iron clusters and closely surrounding Fe-N4 active sites. Unique to this work is that the mechanically stable mesoporous carbon-matrix structure (79 nm in pore size) with well-dispersed nitrogen-coordinated Fe single atom-cluster is synthesized via rapid thermal annealing (RTA) within only minutes using a self-assembled bottlebrush block copolymer (BBCP) melamine-formaldehyde resin composite template. The resulting porous structure and domain size can be tuned with the degree of polymerization of the BBCP backbone, which increases the electrochemically active surface area and improves electron transfer and mass transport for an effective OER process. The optimized electrocatalyst shows a required potential of 1.48 V (versus RHE) to obtain the current density of 10 mA/cm2 in 1 M KOH aqueous electrolyte and a small Tafel slope of 55 mV/decade at a given overpotential of 250 mV, which is significantly lower than recently reported earth-abundant electrocatalysts. Importantly, the Fe single-atom nitrogen coordination environment facilitates the surface reconstruction into a highly active oxyhydroxide under OER conditions, as revealed by X-ray photoelectron spectroscopy and in situ Raman spectroscopy, while the atomic clusters boost the single atoms reactive sites to prevent demetalation during the OER process. Density functional theory (DFT) calculations support that the iron nitrogen environment and reconstructed oxyhydroxides are electrocatalytically active sites as the kinetics barrier is largely reduced. This work has opened a new avenue for simple, rapid synthesis of inexpensive, earth-abundant, tailorable, mechanically stable, mesoporous carbon-coordinated single-atom electrocatalysts that can be used for renewable energy production.

3.
Liver Int ; 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38506430

RESUMEN

BACKGROUND & AIMS: Many systematic reviews explore the association of non-alcoholic fatty liver disease (NAFLD) with mortality, but none of them explores sex-based differences in detail. We aimed to assess whether NAFLD is associated with cause-specific mortality, all-cause mortality, and cancer incidence in both men and women. METHODS: The PubMed, Embase, and Medline databases were searched from inception through April 2023 for eligible studies. We separately pooled relative risks (RRs) for men and women using a random effects model. Subsequently, the RRs and 95% CIs (confidence intervals) in each study were used to calculate the women-to-men ratio of RRs (RRR). Furthermore, subgroup analyses were performed to explore the robustness of outcomes. The random-effects model was employed to conduct sensitivity analyses to determine the impact of specific studies on the overall findings. RESULTS: The meta-analysis included nine cohort studies comprising 557 614 patients with NAFLD were chosen. Women were 44% more likely than men to get cancer among those with NAFLD (RRR: 1.44; 95% CI: 1.02-2.04; p = .039). However, no sex-related differences were observed between NAFLD and all-cause mortality (RRR: 1.06; 95% CI: 0.56-2.01; p = .861), liver-related mortality (RRR: 1.06; 95% CI: 0.02-69.82; p = .977), cardiovascular mortality (RRR: 1; 95% CI: 0.65-1.53; p = .987) and liver cancer (RRR: 0.76; 95% CI: 0.43-1.36; p = .36). CONCLUSIONS: There may be sex variations between NAFLD and the risk of cancer, with the connection being stronger in females than in males.

4.
J Am Chem Soc ; 146(12): 8598-8606, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38465613

RESUMEN

This study outlines the preparation and characterization of a unique superlattice composed of indium oxide (In2O3) vertex-truncated nano-octahedra, along with an exploration of its response to high-pressure conditions. Transmission electron microscopy and scanning transmission electron microscopy were employed to determine the average circumradius (15.2 nm) of these vertex-truncated building blocks and their planar superstructure. The resilience and response of the superlattice to pressure variations, peaking at 18.01 GPa, were examined using synchrotron-based wide-angle X-ray scattering (WAXS) and small-angle X-ray scattering (SAXS) techniques. The WAXS data revealed no phase transitions, reinforcing the stability of the 2D superlattice composed of random layers in alignment with a p31m planar symmetry as discerned by SAXS. Notably, the SAXS data also unveiled a pressure-induced, irreversible translation of octahedra and ligand interaction occurring within the random layer. Through our examination of these pressure-sensitive behaviors, we identified a distinctive translation model inherent to octahedra and observed modulation of the superlattice cell parameter induced by pressure. This research signifies a noteworthy advancement in deciphering the intricate behaviors of 2D superlattices under a high pressure.

5.
Small ; 20(11): e2305746, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37941496

RESUMEN

Redox-induced interconversions of metal oxidation states typically result in multiple phase boundaries that separate chemically and structurally distinct oxides and suboxides. Directly probing such multi-interfacial reactions is challenging because of the difficulty in simultaneously resolving the multiple reaction fronts at the atomic scale. Using the example of CuO reduction in H2 gas, a reaction pathway of CuO → monoclinic m-Cu4 O3 → Cu2 O is demonstrated and identifies interfacial reaction fronts at the atomic scale, where the Cu2 O/m-Cu4 O3 interface shows a diffuse-type interfacial transformation; while the lateral flow of interfacial ledges appears to control the m-Cu4 O3 /CuO transformation. Together with atomistic modeling, it is shown that such a multi-interface transformation results from the surface-reaction-induced formation of oxygen vacancies that diffuse into deeper atomic layers, thereby resulting in the formation of the lower oxides of Cu2 O and m-Cu4 O3 , and activate the interfacial transformations. These results demonstrate the lively dynamics at the reaction fronts of the multiple interfaces and have substantial implications for controlling the microstructure and interphase boundaries by coupling the interplay between the surface reaction dynamics and the resulting mass transport and phase evolution in the subsurface and bulk.

6.
Sci Adv ; 9(44): eadh5565, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37910618

RESUMEN

The microscopic mechanisms underpinning the spontaneous surface passivation of metals from ubiquitous water have remained largely elusive. Here, using in situ environmental electron microscopy to atomically monitor the reaction dynamics between aluminum surfaces and water vapor, we provide direct experimental evidence that the surface passivation results in a bilayer oxide film consisting of a crystalline-like Al(OH)3 top layer and an inner layer of amorphous Al2O3. The Al(OH)3 layer maintains a constant thickness of ~5.0 Å, while the inner Al2O3 layer grows at the Al2O3/Al interface to a limiting thickness. On the basis of experimental data and atomistic modeling, we show the tunability of the dissociation pathways of H2O molecules with the Al, Al2O3, and Al(OH)3 surface terminations. The fundamental insights may have practical significance for the design of materials and reactions for two seemingly disparate but fundamentally related disciplines of surface passivation and catalytic H2 production from water.

7.
Nano Lett ; 23(8): 3476-3483, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37040582

RESUMEN

This study demonstrates an atomic composition manipulation on Pt-Ni nano-octahedra to enhance their electrocatalytic performance. By selectively extracting Ni atoms from the {111} facets of the Pt-Ni nano-octahedra using gaseous carbon monoxide at an elevated temperature, a Pt-rich shell is formed, resulting in an ∼2 atomic layer Pt-skin. The surface-engineered octahedral nanocatalyst exhibits a significant enhancement in both mass activity (∼1.8-fold) and specific activity (∼2.2-fold) toward the oxygen reduction reaction compared with its unmodified counterpart. After 20,000 potential cycles of durability tests, the surface-etched Pt-Ni nano-octahedral sample shows a mass activity of 1.50 A/mgPt, exceeding the initial mass activity of the unetched counterpart (1.40 A/mgPt) and outperforming the benchmark Pt/C (0.18 A/mgPt) by a factor of 8. DFT calculations predict this improvement with the Pt surface layers and support these experimental observations. This surface-engineering protocol provides a promising strategy for developing novel electrocatalysts with improved catalytic features.

8.
Proc Natl Acad Sci U S A ; 120(13): e2215189120, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-36943886

RESUMEN

The Mars-van Krevelen mechanism is the foundation for oxide-catalyzed oxidation reactions and relies on spatiotemporally separated redox steps. Herein, we demonstrate the tunability of this separation with peroxide species formed by excessively adsorbed oxygen, thereby modifying the catalytic activity and selectivity of the oxide. Using CuO as an example, we show that a surface layer of peroxide species acts as a promotor to significantly enhance CuO reducibility in favor of H2 oxidation but conversely as an inhibitor to suppress CuO reduction against CO oxidation. Together with atomistic modeling, we identify that this opposite effect of the peroxide on the two oxidation reactions stems from its modification on coordinately unsaturated sites of the oxide surface. By differentiating the chemical functionality between lattice oxygen and peroxide, these results are closely relevant to a wide range of catalytic oxidation reactions using excessively adsorbed oxygen to activate lattice oxygen and tune the activity and selectivity of redox sites.

9.
J Am Chem Soc ; 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36763977

RESUMEN

Noncatalytic gas-solid reactions are a large group of heterogeneous reactions that are usually assumed to occur irreversibly because of the strong driving force to favor the forward direction toward the product formation. Using the example of Ni oxidation into NiO with CO2, herein, we demonstrate the existence of the reverse element that results in the NiO reduction from the countering effect of the gaseous product of CO. Using in situ electron microscopy observations and atomistic modeling, we show that the oxidation process occurs via preferential CO2 adsorption along step edges that results in step-flow growth of NiO layers, and the presence of Ni atoms on the flat NiO surface promotes the nucleation of NiO layers. Simultaneously, the NiO reduction happens via preferential step-edge adsorption of CO that leads to the receding motion of atomic steps, and the presence of Ni vacancies in the NiO surface facilitates the CO-adsorption-induced surface pitting. Temperature and CO2 pressure effect maps are constructed to illustrate the spatiotemporal dynamics of the competing NiO redox reactions. These results demonstrate the rich gas-solid surface reaction dynamics induced by the coexisting forward and reverse reaction elements and have practical applicability in manipulating gas-solid reactions via controlling the gas environment or atomic structure of the solid surface to steer the reaction toward the desired direction.

10.
ACS Appl Mater Interfaces ; 15(1): 963-972, 2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36537553

RESUMEN

The ε-LiVOPO4 cathode for Li-ion batteries has attracted wide attention with its multivalent electronic states and improved discharge capacity of over 300 mAh/g. Oxygen loss stands as a potential cause for structural degradations of the ε-LiVOPO4 cathode and its derivatives but has been barely studied. Through in situ environmental transmission electron microscopy, we probe lattice oxygen loss and the associated structural degradations by spatially and temporally resolving the atomic-scale structural dynamics and phase transformation pathways in ε-LiVOPO4. We demonstrate that the mild oxygen loss at 400 °C induces a topotactic phase transformation of ε-LiVOPO4 → α-Li3V2(PO4)3 in the particle surface via a nucleation and growth mechanism, leading to the formation of a core-shell configuration. The phase transformation can be reversed by switching to an oxidizing environment, in which the α-Li3V2(PO4)3 is reoxidized to ε-LiVOPO4. By contrast, oxygen loss at higher temperatures of 500 and 600 °C results in a high concentration of oxygen vacancies that subsequently induces irreversible structural damages including lattice amorphization and formation of nanocavities. This work illustrates the fundamental mechanisms governing the structural failure of oxide cathodes and underlines possible strategies to overcome such issues by exploiting environmental constraints.

11.
ACS Appl Mater Interfaces ; 14(34): 38795-38806, 2022 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-35972398

RESUMEN

The surface of the layered transition metal oxide cathode plays an important role in its function and degradation. Modification of the surface structure and chemistry is often necessary to overcome the debilitating effect of the native surface. Here, we employ a chemical reduction method using CaI2 to modify the native surface of single-crystalline layered transition metal oxide cathode particles. High-resolution transmission electron microscopy shows the formation of a conformal cubic phase at the particle surface, where the outmost layer is enriched with Ca. The modified surface significantly improves the long-term capacity retention at low rates of cycling, yet the rate capability is compromised by the impeded interfacial kinetics at high voltages. The lack of oxygen vacancy generation in the chemically induced surface phase transformation likely results in a dense surface layer that accounts for the improved electrochemical stability and impeded Li-ion diffusion. This work highlights the strong dependence of the electrode's (electro)chemical stability and intercalation kinetics on the surface structure and chemistry, which can be further tailored by the chemical reduction method.

12.
Nature ; 607(7920): 708-713, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35896645

RESUMEN

Most engineering materials are based on multiphase microstructures produced either through the control of phase equilibria or by the fabrication of different materials as in thin-film processing. In both processes, the microstructure relaxes towards equilibrium by mismatch dislocations (or geometric misfit dislocations) across the heterophase interfaces1-5. Despite their ubiquitous presence, directly probing the dynamic action of mismatch dislocations has been unachievable owing to their buried nature. Here, using the interfacial transformation of copper oxide to copper as an example, we demonstrate the role of mismatch dislocations in modulating oxide-to-metal interfacial transformations in an intermittent manner, by which the lateral flow of interfacial ledges is pinned at the core of mismatch dislocations until the dislocation climbs to the new oxide/metal interface location. Together with atomistic calculations, we identify that the pinning effect is associated with the non-local transport of metal atoms to fill vacancies at the dislocation core. These results provide mechanistic insight into solid-solid interfacial transformations and have substantial implications for utilizing structural defects at buried interfaces to modulate mass transport and transformation kinetics.

13.
J Phys Chem Lett ; 13(24): 5597-5604, 2022 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-35700476

RESUMEN

Using ambient-pressure X-ray photoelectron spectroscopy and Auger electron spectroscopy to monitor the reduction of Cu2O in H2, we identify the formation of an intermediate, oxygen-deficient Cu2O phase and its progressive inward growth into the deeper region of the oxide. Complemented by atomistic modeling, we show that the oxygen-deficient Cu2O formation occurs via molecular H2 adsorption at the Cu2O surface, which results in the loss of lattice oxygen from the formation of H2O molecules that desorb spontaneously from the oxide surface. The resulting oxygen-deficient Cu2O is a stable intermediate that persists before the Cu2O is fully reduced to metallic Cu. The oxygen vacancy-induced charge of the coordinating Cu atoms results in a satellite feature in Cu LMM, which can be used as a fingerprint to identify nonstoichiometry in oxides and local charge transfer induced by the nonstoichiometry.

14.
BMJ Open ; 12(5): e054158, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35580965

RESUMEN

INTRODUCTION: Osteoporosis (OP) is a prevalent skeletal disease with high mortality and morbidity, followed by acute and chronic back pain, severe spinal deformity and dysfunction. First-line drugs for OP work through antiresorptive or anabolic mechanisms. Although with good efficacy, these drugs still have certain limitations in clinical application due to delivery routes, medication cycles and cost issues. Nowadays, statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) appear to be potentially promising drugs for OP. Despite the controversy, previous studies have shown the efficacy of statins in treating OP. Other studies have further indicated that the therapeutic effect of OP in statin-treated patients is dose dependent. However, scientists have not yet reached a consensus on the use of statins for the treatment or which statin to choose first. This study aims to review the literature, ascertaining the relative efficacy and safety of statins for patients with OP using a Bayesian network meta-analysis. METHODS AND ANALYSIS: We will systematically search the following databases: MEDLINE, EMBASE, Web of Science, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, Wanfang Database, China Science and Technology Journal Database, Chinese BioMedical Literature Database and preprint servers to include randomised controlled trials that compare different statins for treating OP. Primary outcomes are the incidence of overall fractures and bone mineral density changes. Secondary outcomes contain adverse effects and bone turnover markers. All items of this review will comply with the Cochrane Handbook, and the quality of evidence will be evaluated by Grading of Recommendations Assessment, Development and Evaluation. A traditional pairwise meta-analysis and the Bayesian network meta-analysis will be performed to compare the efficacy of different statins. ETHICS AND DISSEMINATION: Ethical approval is not required since this is a protocol study for meta-analyses. Results will be submitted to a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42021242619. SEARCH DATES: From database inception to February 2022.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas , Osteoporosis , Teorema de Bayes , Densidad Ósea , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Metaanálisis como Asunto , Metaanálisis en Red , Osteoporosis/tratamiento farmacológico , Revisiones Sistemáticas como Asunto
15.
Proc Natl Acad Sci U S A ; 119(14): e2117899119, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35344429

RESUMEN

SignificanceDynamically understanding the microscopic processes governing ordering transformations has rarely been attained. The situation becomes even more challenging for nanoscale alloys, where the significantly increased surface-area-to-volume ratio not only opens up a variety of additional freedoms to initiate an ordering transformation but also allows for kinetic interplay between the surface and bulk due to their close proximity. We provide direct evidence of the microscopic processes controlling the ordering transformation through the surface-bulk interplay in Pt-Fe nanoalloys and new features rendered by variations in alloy composition and chemical stimuli. These results provide a mechanistic detail of ordering transformation phenomena which are widely relevant to nanoalloys as chemical ordering occurs in most multicomponent materials under suitable environmental bias.

16.
Front Public Health ; 10: 835286, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35284367

RESUMEN

Osteoporosis is alarming problem due to aggravation of global aging, especially in China. Osteoporotic fracture (OF) is one of the most severe consequents of osteoporosis. Many previous studies found that environmental factors had adverse effects on human health. Cold temperature was associated with OF and bone metabolism in prior observational and experimental researches. However, few studies had been conducted on the acute effect of low temperature and OF. Data on daily meteorological factors and hospitalizations for OF were collected from Wuhan, China, between January 1, 2017 to December 24, 2019. Apparent temperature (AT), comprehensively considered a variety of environmental factors, was calculated by ambient temperature, relative humidity and wind speed. A generalized linear regression model combined with distributed lag non-linear regression model (DLNM) with quasi-Poisson link was used to explore the association between AT and the number of hospitalizations for OF. Subgroup analyses stratified by gender, age and the history of fracture were applied for detecting susceptible people. The exposure-response curve of AT and OF were generally U-shaped with lowest point at 25.8°C. The significant relationship of AT-OF existed only in cold effect (-2.0 vs. 25.8°C) while not in warm effect (37.0 vs. 25.8°C). Statistically significant risks of OF for cold effects were only found in females [RR = 1.12 (95%CI: 1.02, 1.24) at lag 2 day], aged <75 years old [RR = 1.18 (95%CI: 1.04, 1.33) and 1.17 (95%CI: 1.04, 1.33) at lag 2 and 3 days, respectively] and people with history of fracture [RR = 1.39 (95%CI: 1.02, 1.90) and 1.27 (95%CI: 1.05, 1.53) at lag 1 and 2 days, respectively]. The significant associations of AT on OF were only found in cold effect. The females, people aged <75 years and people with history of fracture possibly appeared to be more vulnerable. Public health departments should pay attention to the negative effect of cold AT and take measures in time.


Asunto(s)
Osteoporosis , Fracturas Osteoporóticas , Anciano , Frío , Femenino , Hospitalización , Humanos , Osteoporosis/epidemiología , Fracturas Osteoporóticas/epidemiología , Temperatura
17.
J Phys Chem Lett ; 13(10): 2396-2403, 2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35257576

RESUMEN

Identifying the atomic structure and formation mechanism of intermediates during chemical transformations is challenging because of their short-lived nature. With a combination of microscopic and spectroscopic measurements and first-principles calculations, herein we report the formation of a metastable intermediate Cu-O/OH superstructure during the reaction of hydrogen with oxygen-covered Cu(110). This superstructure resembles the parent c(6 × 2)-O phase and can be termed as c(6 × 2)-(4O+2OH) with OH groups occupying the missing Cu sites between isolated Cu atoms. Using atomistic calculations, we elucidate the reaction pathways leading to the c(6 × 2)-(4O+2OH) formation via both molecular and dissociative H2 adsorption. These results demonstrate the complex surface dynamics resulting from the parallel reaction pathways and may open up the possibility of directing the reaction dynamics by deliberately manipulating transient surface structure and composition.

18.
Chem Rev ; 122(6): 5641-5681, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35025511

RESUMEN

Layered lithium transition metal oxides derived from LiMO2 (M = Co, Ni, Mn, etc.) have been widely adopted as the cathodes of Li-ion batteries for portable electronics, electric vehicles, and energy storage. Oxygen loss in the layered oxides is one of the major factors leading to cycling-induced structural degradation and its associated fade in electrochemical performance. Herein, we review recent progress in understanding the phenomena of oxygen loss and the resulting structural degradation in layered oxide cathodes. We first present the major driving forces leading to the oxygen loss and then describe the associated structural degradation resulting from the oxygen loss. We follow this analysis with a discussion of the kinetic pathways that enable oxygen loss, and then we address the resulting electrochemical fade. Finally, we review the possible approaches toward mitigating oxygen loss and the associated electrochemical fade as well as detail novel analytical methods for probing the oxygen loss.

19.
Front Endocrinol (Lausanne) ; 12: 729565, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34790166

RESUMEN

Background: Despite extensive research, the papillary thyroid carcinoma (PTC) ecosystem is poorly characterized and, in particular, locoregional progression. Available evidence supports that single-cell transcriptome sequencing (Sc-RNA seq) can dissect tumor ecosystems. Methods: Tissue samples from one PTC patient, including matched primary tumor (Ca), lymph node (LN) metastasis, and paracancerous tissue (PCa), were subjected to Sc-RNA seq with 10×Genomics. Dual-label immunofluorescence and immunohistochemistry were used to confirm the existence of cell subtypes in a separate cohort. Results: 11,805 cell transcriptomes were profiled, cell landscapes of PTC were composed of malignant follicular epithelial cells (MFECs), CD8+ and CD4+ T cells, B cells, vascular endothelial cells, fibroblasts and cancer-associated fibroblasts (CAFs). Between Ca and LN ecosystems, the proportions of MFEC and interstitial cells were similar, less than 1/25(229/6,694, 361/3,895), while the proportion of normal follicular epithelial cells (NFECs) and interstitial cells was > 2 in PCa (455/171). NFECs in PCa formed a separate cluster, while MFECs in Ca and LN exhibited a profound transcriptional overlap, and the interstitial cells among these samples had an overall concordance in their identity and representation, albeit with some distinctions in terms of the cell percentage per subset. A fraction of the B cell subpopulation in Ca expressed inhibitory receptors, while their respective ligand genes were clearly transcribed in T cell and malignant epithelial cell clusters, while some CD8+ T cells in both Ca and LN produced high levels of inhibitory receptors whose respective ligands were overexpressed in some CD4+ T cells. Three CAF subtypes in Ca and LN were identified, which may be due to mutual transitions. Conclusions: Our data provide new insights into the PTC ecosystem and highlight the differences in ecosystems in PTC progression, which updates our understanding of PTC biology and will improve individualized patient treatment.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Regulación Neoplásica de la Expresión Génica , Análisis de la Célula Individual/métodos , Cáncer Papilar Tiroideo/patología , Neoplasias de la Tiroides/patología , Transcriptoma , Biomarcadores de Tumor/genética , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/patología , Fibroblastos Asociados al Cáncer/metabolismo , Fibroblastos Asociados al Cáncer/patología , Estudios de Cohortes , Células Endoteliales/metabolismo , Células Endoteliales/patología , Femenino , Humanos , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/patología , Persona de Mediana Edad , Pronóstico , Cáncer Papilar Tiroideo/genética , Cáncer Papilar Tiroideo/metabolismo , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/metabolismo
20.
J Phys Chem Lett ; 12(39): 9547-9556, 2021 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-34570978

RESUMEN

Reducibility is key for the use of bulk metal oxides in chemical transformations involving redox reactions, but probing microscopic processes of oxide reduction is challenging. This is because the insulating nature of bulk oxides restricts ion and electron spectroscopic measurements of oxide surfaces. Herein, using a combination of environmental transmission electron microscopy and atomistic modeling, we report direct in situ atomic-scale observations of the surface and subsurface dynamics and show that the hydrogen-induced CuO reduction occurs through the receding motion of Cu-O/Cu bilayer steps at the surface, the formation of the partially reduced CuO superstructure by the self-ordering of O vacancies in the subsurface, and the collapse of Cu-O layers in the bulk. All these substeps can be traced back to the progressively increased concentration and activity of O vacancies in the surface and subsurface of the oxide, thereby leading to the self-accelerated oxide reduction. These results demonstrate the microscopic details that may have a broader applicability in modulating various redox processes.

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