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1.
Nature ; 605(7909): 325-331, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35418683

RESUMEN

Cellular reprogramming can manipulate the identity of cells to generate the desired cell types1-3. The use of cell intrinsic components, including oocyte cytoplasm and transcription factors, can enforce somatic cell reprogramming to pluripotent stem cells4-7. By contrast, chemical stimulation by exposure to small molecules offers an alternative approach that can manipulate cell fate in a simple and highly controllable manner8-10. However, human somatic cells are refractory to chemical stimulation owing to their stable epigenome2,11,12 and reduced plasticity13,14; it is therefore challenging to induce human pluripotent stem cells by chemical reprogramming. Here we demonstrate, by creating an intermediate plastic state, the chemical reprogramming of human somatic cells to human chemically induced pluripotent stem cells that exhibit key features of embryonic stem cells. The whole chemical reprogramming trajectory analysis delineated the induction of the intermediate plastic state at the early stage, during which chemical-induced dedifferentiation occurred, and this process was similar to the dedifferentiation process that occurs in axolotl limb regeneration. Moreover, we identified the JNK pathway as a major barrier to chemical reprogramming, the inhibition of which was indispensable for inducing cell plasticity and a regeneration-like program by suppressing pro-inflammatory pathways. Our chemical approach provides a platform for the generation and application of human pluripotent stem cells in biomedicine. This study lays foundations for developing regenerative therapeutic strategies that use well-defined chemicals to change cell fates in humans.


Asunto(s)
Diferenciación Celular , Reprogramación Celular , Células Madre Pluripotentes Inducidas , Linaje de la Célula , Humanos , Células Madre Pluripotentes Inducidas/citología
2.
J Cell Mol Med ; 28(8): e18247, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38520212

RESUMEN

Malignant melanoma (MM) is a highly aggressive and deadly form of skin cancer, primarily caused by recurrence and metastasis. Therefore, it is crucial to investigate the regulatory mechanisms underlying melanoma recurrence and metastasis. Our study has identified a potential targeted regulatory relationship between LINC02202, miR-526b-3p and XBP1 in malignant melanoma. Through the regulation of the miR-526b-3p/XBP1 signalling pathway, LINC02202 may play a role in tumour progression and immune infiltration and inhibiting the expression of LINC02202 can increase the efficacy of immunotherapy for melanoma. Our findings shed light on the impact of LINC02202/XBP1 on the phenotype and function of malignant melanoma cells. Furthermore, this study provides a theoretical foundation for the development of novel immunotherapy strategies for malignant melanoma.


Asunto(s)
Melanoma , MicroARNs , Neoplasias Cutáneas , Humanos , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/patología , MicroARNs/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Línea Celular Tumoral , Neoplasias Cutáneas/genética , Sistemas de Liberación de Medicamentos , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Proteína 1 de Unión a la X-Box/genética , Proteína 1 de Unión a la X-Box/metabolismo
3.
J Am Chem Soc ; 146(9): 6199-6208, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38394360

RESUMEN

A reliable solid electrolyte interphase (SEI) on the metallic Zn anode is imperative for stable Zn-based aqueous batteries. However, the incompatible Zn-ion reduction processes, scilicet simultaneous adsorption (capture) and desolvation (repulsion) of Zn2+(H2O)6, raise kinetics and stability challenges for the design of SEI. Here, we demonstrate a tandem chemistry strategy to decouple and accelerate the concurrent adsorption and desolvation processes of the Zn2+ cluster at the inner Helmholtz layer. An electrochemically assembled perforative mesopore SiO2 interphase with tandem hydrophilic -OH and hydrophobic -F groups serves as a Janus mesopores accelerator to boost a fast and stable Zn2+ reduction reaction. Combining in situ electrochemical digital holography, molecular dynamics simulations, and spectroscopic characterizations reveals that -OH groups capture Zn2+ clusters from the bulk electrolyte and then -F groups repulse coordinated H2O molecules in the solvation shell to achieve the tandem ion reduction process. The resultant symmetric batteries exhibit reversible cycles over 8000 and 2000 h under high current densities of 4 and 10 mA cm-2, respectively. The feasibility of the tandem chemistry is further evidenced in both Zn//VO2 and Zn//I2 batteries, and it might be universal to other aqueous metal-ion batteries.

4.
Proc Natl Acad Sci U S A ; 118(14)2021 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-33785600

RESUMEN

The contraction of heart cells is controlled by the intermolecular signaling between L-type Ca2+ channels (LCCs) and ryanodine receptors (RyRs), and the nanodistance between them depends on the interaction between junctophilin-2 (JPH2) in the sarcoplasmic reticulum (SR) and caveolin-3 (CAV3) in the transversal tubule (TT). In heart failure, decreased expression of JPH2 compromises LCC-RyR communication leading to deficient blood-pumping power. In the present study, we found that JPH2 and CAV3 transcription was concurrently regulated by serum response factor (SRF) and myocardin. In cardiomyocytes from torpid ground squirrels, compared with those from euthermic counterparts, myocardin expression was up-regulated, which boosted both JPH2 and CAV3 expression. Transmission electron microscopic imaging showed that the physical coupling between TTs and SRs was tightened during hibernation and after myocardin overexpression. Confocal Ca2+ imaging under the whole-cell patch clamp condition revealed that these changes enhanced the efficiency of LCC-RyR intermolecular signaling and fully compensated the adaptive down-regulation of LCCs, maintaining the power of heart contraction while avoiding the risk of calcium overload during hibernation. Our finding not only revealed an essential molecular mechanism underlying the survival of hibernating mammals, but also demonstrated a "reverse model of heart failure" at the molecular level, suggesting a strategy for treating heart diseases.


Asunto(s)
Señalización del Calcio , Hibernación , Miocitos Cardíacos/metabolismo , Animales , Caveolinas/genética , Caveolinas/metabolismo , Células Cultivadas , Acoplamiento Excitación-Contracción , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas Nucleares/sangre , Proteínas Nucleares/metabolismo , Sciuridae , Transactivadores/sangre , Transactivadores/metabolismo
5.
J Environ Manage ; 352: 120049, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38232592

RESUMEN

Gallium arsenide (GaAs) is the most widely used second-generation semiconductor material. However, a large amount of GaAs scrap is generated at various stages of the GaAs wafer production process. Volatile GaAs clusters are inevitably generated during the process of GaAs vacuum thermal decomposition, resulting in lower purity of the recovered arsenic and the loss of gallium. In this study, thermodynamic analysis and dynamics simulation were combined to discuss the possibility of separating GaAs clusters and arsenic from a microscopic perspective. A vacuum thermal decomposition-directional condensation recovery process for GaAs scrap was proposed. By properly adjusting the separation parameters such as heating temperature, holding time and raw material size, high purity of gallium (99.99%) and arsenic (99.5%) were directly recovered under a system pressure of 1 Pa, heating temperature of 1323 K, holding time of 3 h, and GaAs scrap size of 2.5 cm. GaAs clusters were also recovered in powder form. The problem of difficult separation of GaAs clusters from arsenic was effectively solved by this method, and the purity of recovered arsenic was greatly improved. No additives are required and no waste liquid or gas emission in the whole process. The complexity of subsequent arsenic purification operations and the threat of arsenic containing waste to the environment were reduced as well.


Asunto(s)
Arsénico , Arsenicales , Galio
6.
Angew Chem Int Ed Engl ; 63(20): e202402987, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38436516

RESUMEN

Zinc-based aqueous batteries (ZABs) are attracting extensive attention due to the low cost, high capacity, and environmental benignity of the zinc anode. However, their application is still hindered by the undesired zinc dendrites. Despite Zn-surface modification being promising in relieving dendrites, a thick separator (i.e. glass fiber, 250-700 µm) is still required to resist the dendrite puncture, which limits volumetric energy density of battery. Here, we pivot from the traditional interphase plus extra separator categories, proposing an all-in-one ligand buffer layer (ca. 20 µm) to effectively modulate the Zn2+ transfer and deposition behaviors proved by in situ electrochemical digital holography. Experimental characterizations and density functional theory simulations further reveal that the catechol groups in the buffer layer can accelerate the Zn2+ reduction reaction (ZRR) through the electron-donating p-π conjugation effect, decreasing the negative charge in the coordination environment. Without extra separators, the elaborated system endows low polarization below 28.2 mV, long lifespan of 4950 h at 5 mA cm-2 in symmetric batteries, and an unprecedented volumetric energy density of 99.2 Wh L-1 based on the whole pouch cells. The concomitantly "separator-free" and "dendrite-free" conjugation effect with an accelerated ZRR process could foster the progression of metallic anodes and benefit energetic aqueous batteries.

7.
Circulation ; 145(15): 1154-1168, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35317609

RESUMEN

BACKGROUND: Cardiac ischemia/reperfusion (I/R) injury has emerged as an important therapeutic target for ischemic heart disease, the leading cause of morbidity and mortality worldwide. At present, there is no effective therapy for reducing cardiac I/R injury. CaMKII (Ca2+/calmodulin-dependent kinase II) plays a pivotal role in the pathogenesis of severe heart conditions, including I/R injury. Pharmacological inhibition of CaMKII is an important strategy in the protection against myocardial damage and cardiac diseases. To date, there is no drug targeting CaMKII for the clinical therapy of heart disease. Furthermore, at present, there is no selective inhibitor of CaMKII-δ, the major CaMKII isoform in the heart. METHODS: A small-molecule kinase inhibitor library and a high-throughput screening system for the kinase activity assay of CaMKII-δ9 (the most abundant CaMKII-δ splice variant in human heart) were used to screen for CaMKII-δ inhibitors. Using cultured neonatal rat ventricular myocytes, human embryonic stem cell-derived cardiomyocytes, and in vivo mouse models, in conjunction with myocardial injury induced by I/R (or hypoxia/reoxygenation) and CaMKII-δ9 overexpression, we sought to investigate the protection of hesperadin against cardiomyocyte death and cardiac diseases. BALB/c nude mice with xenografted tumors of human cancer cells were used to evaluate the in vivo antitumor effect of hesperadin. RESULTS: Based on the small-molecule kinase inhibitor library and screening system, we found that hesperadin, an Aurora B kinase inhibitor with antitumor activity in vitro, directly bound to CaMKII-δ and specifically blocked its activation in an ATP-competitive manner. Hesperadin functionally ameliorated both I/R- and overexpressed CaMKII-δ9-induced cardiomyocyte death, myocardial damage, and heart failure in both rodents and human embryonic stem cell-derived cardiomyocytes. In addition, in an in vivo BALB/c nude mouse model with xenografted tumors of human cancer cells, hesperadin delayed tumor growth without inducing cardiomyocyte death or cardiac injury. CONCLUSIONS: Here, we identified hesperadin as a specific small-molecule inhibitor of CaMKII-δ with dual functions of cardioprotective and antitumor effects. These findings not only suggest that hesperadin is a promising leading compound for clinical therapy of cardiac I/R injury and heart failure, but also provide a strategy for the joint therapy of cancer and cardiovascular disease caused by anticancer treatment.


Asunto(s)
Insuficiencia Cardíaca , Daño por Reperfusión Miocárdica , Neoplasias , Animales , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Insuficiencia Cardíaca/patología , Humanos , Indoles , Isquemia/metabolismo , Ratones , Ratones Desnudos , Daño por Reperfusión Miocárdica/patología , Miocitos Cardíacos/metabolismo , Neoplasias/patología , Ratas , Sulfonamidas
8.
J Am Chem Soc ; 145(44): 24284-24293, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37888942

RESUMEN

Zinc metal-based aqueous batteries (ZABs) offer a sustainable, affordable, and safe energy storage alternative to lithium, yet inevitable dendrite formation impedes their wide use, especially under long-term and high-rate cycles. How the battery can survive after dendrite formation remains an open question. Here, we pivot from conventional Zn dendrite growth suppression strategies, introducing proactive dendrite-digesting chemistry via a mesoporous Ti3C2 MXene (MesoTi3C2)-wrapped polypropylene separator. Spectroscopic characterizations and electrochemical evaluation demonstrate that MesoTi3C2, acting as an oxidant, can revive the formed dead Zn0 dendrites into electroactive Zn2+ ions through a spontaneous redox process. Density functional theory reveals that the abundant edge-Ti-O sites in our MesoTi3C2 facilitate high oxidizability and electron transfer from Zn0 dendrites compared to their in-plane counterparts. The resultant asymmetrical cell demonstrates remarkable ultralong cycle life of 2200 h at a practical current of 5 mA cm-2 with a low overpotential (<50 mV). The study reveals the unexpected edge effect of mesoporous MXenes and uncovers a new proactive dendrite-digesting chemistry to survive ZABs, albeit with inevitable dendrite formation.

9.
EMBO Rep ; 22(7): e52481, 2021 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-34121311

RESUMEN

Receptor activator of NF-κB ligand (RANKL) is essential for osteoclast formation and bone remodeling. Nevertheless, the cellular source of RANKL for osteoclastogenesis has not been fully uncovered. Different from peripheral adipose tissue, bone marrow (BM) adipose lineage cells originate from bone marrow mesenchymal stromal cells (BMSCs). Here, we demonstrate that adiponectin promoter-driven Cre expression (AdipoqCre ) can target bone marrow adipose lineage cells. We cross the AdipoqCre mice with ranklfl/fl mice to conditionally delete RANKL from BM adipose lineage cells. Conditional deletion of RANKL increases cancellous bone mass of long bones in mice by reducing the formation of trabecular osteoclasts and inhibiting bone resorption but does not affect cortical bone thickness or resorption of calcified cartilage. AdipoqCre ; ranklfl/fl mice exhibit resistance to estrogen deficiency and rosiglitazone (ROS)-induced trabecular bone loss but show bone loss induced by unloading. BM adipose lineage cells therefore represent an essential source of RANKL for the formation of trabecula osteoclasts and resorption of cancellous bone during remodeling under physiological and pathological conditions. Targeting bone marrow adiposity is a promising way of preventing pathological bone loss.


Asunto(s)
Resorción Ósea , Osteoclastos , Tejido Adiposo , Animales , Médula Ósea , Células de la Médula Ósea , Resorción Ósea/genética , Diferenciación Celular , Ratones
10.
Skin Res Technol ; 29(6): e13321, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37357644

RESUMEN

BACKGROUND: Cutaneous squamous cell carcinoma (CSCC) is a severe malignancy derived from the skin. Mounting evidence suggests that circular RNAs (circRNAs) participate in diverse biological functions in human cancers, containing CSCC. However, the biological functions and underlying mechanism of hsa_circ_0005085 in CSCC have not been clearly studied. METHODS: Expression levels of hsa_circ_0005085, microRNA-186-5p (miR-186-5p), and Laminin subunit gamma 1 (LAMC1) were detected by reverse transcription-quantitative polymerase chain reaction. Cell counting kit-8 assay, colony formation assay, and 5-Ethynyl-2'-deoxyuridine assay were used to assess cell proliferation. Transwell assay was conducted to detect cell migration and invasion. Cell apoptosis was analyzed by flow cytometry. Protein expression of LAMC1, E-cadherin, Snail, and slug were assessed using western blot assay. Using bioinformatics software, the binding between miR-186-5p and hsa_circ_0005085 or LAMC1 was predicted, followed by verification using a dual-luciferase reporter and RNA-Immunoprecipitation. The mouse xenograft model was established to investigate the role of hsa_circ_0005085 in vivo. RESULTS: Hsa_circ_0005085 level was downregulated in CSCC tissues and cells. Overexpression of hsa_circ_0005085 inhibited cell proliferation, migration, invasion, epithelial-mesenchymal transition (EMT), and promoted cell apoptosis in CSCC. MiR-186-5p could restore the effect of hsa_circ_0005085 overexpression on CSCC cells, and the knockdown of LAMC1 reversed the regulation of the miR-186-5p inhibitor. In mechanism, hsa_circ_0005085 served as a sponge for miR-186-5p to regulate LAMC1 expression. Overexpression of hsa_circ_0005085 reduced growth of tumor via miR-186-5p/LAMC1 axis in vivo. CONCLUSION: In our study, hsa_circ_0005085 might inhibit CSCC development by targeting the miR-186-5p/LAMC1 axis, which might provide a promising therapeutic target for CSCC.


Asunto(s)
Carcinoma de Células Escamosas , MicroARNs , Neoplasias Cutáneas , Animales , Humanos , Ratones , Vendajes , Carcinoma de Células Escamosas/genética , Proliferación Celular , Modelos Animales de Enfermedad , MicroARNs/genética , Neoplasias Cutáneas/genética
11.
Allergol Immunopathol (Madr) ; 51(5): 23-28, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37695226

RESUMEN

BACKGROUND: One of the common adverse reactions in patients with pressure ulcers (PU) is sepsis, which is mainly related to microbial infections caused by pathogenic organisms. The activation of nuclear factor kappa-B (NF-κB) frequently occurs in conjunction with pathogenic microbial infections. Proline-serine-threonine-phosphatase-interacting protein 2 (PSTPIP2) is closely related to inflammatory disorders. The role and mechanism of PSTPIP2 in sepsis because of pressure ulcers is unclear. In this study, we discovered that PSTPIP2 was lowly expressed in peripheral blood of patients with sepsis induced by pressure ulcers. METHODS: Peripheral blood was collected from 20 patients with sepsis due to pressure ulcers and 10 healthy controls, and the expression of PSTPIP2 in peripheral blood was discovered by polymerase chain reaction and Western blot analysis. Information on the clinical characteristics of patients was summarized, and the expression data of PSTPIP2 were correlated with the patients' acute physiology and chronic health evaluation (APACHE) II score, sequential organ failure assessment (SOFA) score, and C-reactive protein (CRP) and procalcitonin (PCT) scores by Spearman's correlation analysis. One of the main mediators of Gram-negative sepsis is lipopolysaccharide (LPS). In order to establish an in vitro sepsis model, THP-1 cells were treated with LPS, and the cells were transfected with PSTPIP2. Contents of interleukin 6 (IL-6), interleukin 1ß (IL-1ß), and tumor necrosis factor-α (TNF-α) in each group of cells were detected by enzyme-linked--immunosorbent serologic assay, and NF-κB-related proteins were detected by Western blot analysis. RESULTS: When compared to healthy controls, the peripheral blood of patients with pressure sepsis had lower PSTPIP2 expression, which had a negative correlation with the APACHE II, SOFA, CRP, and PCT scores. LPS-induced THP-1 cells expressed less PSTPIP2 than the untreated control cells, and PSTPIP2 transfection decreased IL-6, IL-1ß, and TNF-α levels and inhibited the activation of NF-κB pathway. CONCLUSION: PSTPIP2 is associated with disease severity in patients with pressure ulcer sepsis and has anti-inflammatory effects.


Asunto(s)
Úlcera por Presión , Sepsis , Humanos , Antiinflamatorios , Proteína C-Reactiva , Interleucina-6 , Lipopolisacáridos , FN-kappa B , Gravedad del Paciente , Factor de Necrosis Tumoral alfa
12.
J Am Chem Soc ; 144(26): 11767-11777, 2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35731994

RESUMEN

Constructing hierarchical three-dimensional (3D) mesostructures with unique pore structure, controllable morphology, highly accessible surface area, and appealing functionality remains a great challenge in materials science. Here, we report a monomicelle interface confined assembly approach to fabricate an unprecedented type of 3D mesoporous N-doped carbon superstructure for the first time. In this hierarchical structure, a large hollow locates in the center (∼300 nm in diameter), and an ultrathin monolayer of spherical mesopores (∼22 nm) uniformly distributes on the hollow shells. Meanwhile, a small hole (4.0-4.5 nm) is also created on the interior surface of each small spherical mesopore, enabling the superstructure to be totally interconnected. Vitally, such interconnected porous supraparticles exhibit ultrahigh accessible surface area (685 m2 g-1) and good underwater aerophilicity due to the abundant spherical mesopores. Additionally, the number (70-150) of spherical mesopores, particle size (22 and 42 nm), and shell thickness (4.0-26 nm) of the supraparticles can all be accurately manipulated. Besides this spherical morphology, other configurations involving 3D hollow nanovesicles and 2D nanosheets were also obtained. Finally, we manifest the mesoporous carbon superstructure as an advanced electrocatalytic material with a half-wave potential of 0.82 V (vs RHE), equivalent to the value of the commercial Pt/C electrode, and notable durability for oxygen reduction reaction (ORR).

13.
Small ; 18(6): e2103345, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34862723

RESUMEN

Aqueous zinc-ion batteries are a low-cost and safe energy storage system, but suffer from detrimental side reactions and Zn dendrites due to the strong interactions between Zn2+ and water molecules in the electrolytes, and random Zn2+ deposition on the anode surface. Here, an electrolyte involving a dual-functional additive of polyethylene glycol (PEG) to bypass these issues is reported. The electrolyte can not only tailor the solvation sheath of Zn2+ but also enable favorably oriented deposition of Zn2+ on the anode surface. The dendrite-free Zn anode in Zn//Zn cells is obtained with high Columbic efficiency (98.8%) and long cycling lifespan (1500 h), six times longer than that of electrolyte without PEG at 0.25 mA cm-2 . What is more, the excellent cycling stability of the prepared batteries (Zn//V2 O5 ·1.6 H2 O) suggests that the developed tailoring strategy may propel a promising pathway for stabilizing Zn metal anodes.


Asunto(s)
Polietilenglicoles , Zinc , Suministros de Energía Eléctrica , Electrodos , Electrólitos
14.
Neuroimmunomodulation ; 29(1): 44-54, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34518486

RESUMEN

INTRODUCTION: Glioma is the most aggressive and malignant type of tumors among primary intracranial tumors. miR-433-3p has been verified to be correlated with the formation and progression of many types of cancers. METHODS: In this study, the effects of miR-433-3p and AJUBA on the proliferation, migration, and invasion of glioma and the molecular mechanisms were investigated. We analyzed bioinformatics databases and conducted cell biology experiments to determine that compared with adjacent tissue and normal cells, the expression level of miR-433-3p in glioma tissue and cells was lower, while the expression level of AJUBA was higher. Overexpressing miR-433-3p could significantly inhibit the proliferation, migration, and invasion of glioma cells and promote cell apoptosis. RESULTS: In addition, after overexpressing miR-433-3p and AJUBA, it was found that overexpressing AJUBA could attenuate the inhibitory effect of overexpressing miR-433-3p on the proliferation, migration, and invasion of glioma cells, which suggested that miR-433-3p regulated the biological function of glioma by downregulating AJUBA expression. CONCLUSION: These results proved that miR-433-3p could target to inhibit the expression of AJUBA, thus inhibiting the biological function and malignant progression of glioma.


Asunto(s)
Neoplasias Encefálicas , Glioma , Proteínas con Dominio LIM , MicroARNs , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Glioma/genética , Glioma/metabolismo , Glioma/patología , Humanos , Proteínas con Dominio LIM/biosíntesis , Proteínas con Dominio LIM/genética , Proteínas con Dominio LIM/metabolismo , MicroARNs/genética , MicroARNs/metabolismo
15.
Angew Chem Int Ed Engl ; 61(4): e202114612, 2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-34797581

RESUMEN

Li-CO2 batteries are explored as promising power systems to alleviate environmental issues and to implement space applications. However, sluggish cathode kinetics of CO2 reduction/evolution result in low round-trip efficiency and poor cycling stability of the fabricated energy-storage devices. Herein, we design a heterostructued photocathode comprising carbon nanotube and carbon nitride to accelerate cathode reactions of a Li-CO2 battery under illumination. Benefiting from the unique defective structure of carbon nitride and favorable interfacial charge transfer, the photocathode effectively harvests ultraviolet-visible light to generate abundant photoexcited carriers and coordinates energetic photoelectrons/holes to participate in the discharge/charge reactions, leading to efficient photo-energy utilization in decreasing reaction barriers and enhancing thermodynamic reversibility of Li-CO2 battery. The resulting battery delivers a high round-trip efficiency of 98.8 % (ultralow voltage hysteresis of 0.04 V) and superior cycling stability (86.1 % efficiency retention after 100 cycles).

16.
Small ; 17(25): e2100902, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34028987

RESUMEN

Aqueous zinc-ion batteries (AZIBs) are regarded as one of the most promising alternative technology to lithium-ion batteries on account of their low flammability and cost-benefits. Among various cathode materials in AZIBs, environment-friendly and sustainable organic electrode materials stand out owing to their structural diversity and tunability. However, their limited rate capability and cycle stability remain the obstacles to their further application in AZIBs. Herein, a mixed cathode design strategy including polymerization and carbon materials hybridization is adopted to assemble high-rate and durable AZIBs. Specifically, a polymer/graphene composite cathode with active carbonyls and secondary amine moieties is prepared to construct high-performance aqueous Zn-organic batteries. Furthermore, a hybrid energy storage mechanism involving dual-ion mechanism is confirmed by various ex situ characterization techniques, providing promising battery chemistry. Thus, this work opens up a new path to high performance AZIBs through a rational cathode design.

17.
Circ Res ; 124(9): 1350-1359, 2019 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-30836825

RESUMEN

RATIONALE: ßARs (ß-adrenergic receptors) are prototypical GPCRs (G protein-coupled receptors) that play a pivotal role in sympathetic regulation. In heart cells, ß1AR signaling mediates a global response, including both l-type Ca2+ channels in the sarcolemma/T tubules and RyRs (ryanodine receptors) in the SR (sarcoplasmic reticulum). In contrast, ß2AR mediates local signaling with little effect on the function of SR proteins. OBJECTIVE: To investigate the signaling relationship between ß1ARs and ß2ARs. METHOD AND RESULTS: Using whole-cell patch-clamp analyses combined with confocal Ca2+ imaging, we found that the activation of compartmentalized ß2AR signaling was able to convert the ß1AR signaling from global to local mode, preventing ß1ARs from phosphorylating RyRs that were only nanometers away from sarcolemma/T tubules. This offside compartmentalization was eliminated by selective inhibition of ß2AR, GRK2 (GPCR kinase-2), ßarr1 (ß-arrestin-1), and phosphodiesterase-4. A knockin rat model harboring mutations of the last 3 serine residues of the ß1AR C terminus, a component of the putative ßarr1 binding site and GRK2 phosphorylation site, eliminated the offside compartmentalization conferred by ß2AR activation. CONCLUSIONS: ß2AR stimulation compartmentalizes ß1AR signaling into nanoscale local domains in a phosphodiesterase-4-dependent manner by targeting the C terminus of ß1ARs. This finding reveals a fundamental negative feed-forward mechanism that serves to avoid the cytotoxicity of circulating catecholamine and to sharpen the transient ß1AR response of sympathetic excitation.


Asunto(s)
Receptores Adrenérgicos beta 1/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Adrenérgicos/farmacología , Animales , Células Cultivadas , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 4/metabolismo , Masculino , Mutación , Miocitos Cardíacos/citología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Fosforilación/efectos de los fármacos , Ratas , Ratas Transgénicas , Receptores Adrenérgicos beta 1/química , Receptores Adrenérgicos beta 1/genética , Receptores Adrenérgicos beta 2/genética , Sarcolema/efectos de los fármacos , Sarcolema/metabolismo , Retículo Sarcoplasmático/efectos de los fármacos , Retículo Sarcoplasmático/metabolismo , Transducción de Señal/efectos de los fármacos
18.
Cell Biol Int ; 45(6): 1202-1210, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33501754

RESUMEN

Oncolytic viruses (OV) have shown excellent safety and efficacy in preclinical and clinical studies. Influenza A virus (IAV) is considered a promising oncolytic virus. In this report, we generated a recombinant influenza virus expressing an immune checkpoint blockade agent targeting CTLA4. Using reverse genetics, a recombinant influenza virus, termed rFlu-CTLA4, encoding the heavy chain of a CTLA4 antibody on the PB1 segment and the light chain of the CTLA4 antibody on the PA segment was produced. RFlu-CTLA4 could replicate to high titers, and antibodies were produced in the allantoic fluid of infected eggs. Furthermore, the selective cytotoxicity of the virus was higher in various hepatocellular carcinoma cancer cell lines than in the normal cell line L02 in vitro, as indicated by MTS assays. More importantly, in a subcutaneous H22 mouse hepatocarcinoma model, intratumoral injections of rFlu-CTLA4 inhibited the growth of treated tumors and increased the overall survival of mice compared with injections of the PR8 virus. Taken together, these results warrant further exploration of this novel recombinant influenza virus for its potential use as a single or combination agent for cancer immunotherapy.


Asunto(s)
Antígeno CTLA-4/inmunología , Inmunoterapia/métodos , Virus de la Influenza A/inmunología , Neoplasias/terapia , Viroterapia Oncolítica/métodos , Virus Oncolíticos/inmunología , Animales , Células Hep G2 , Humanos , Ratones , Ratones Endogámicos BALB C
19.
Macromol Rapid Commun ; 42(2): e2000481, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33047435

RESUMEN

This work reports on the transition of a polyamide ultrathick wall microtubes to microvesicles through self-assembly. An amphiphilic polyamide is synthesized first by the solution polycondensation of sodium isophthalate-5-sulfonate (SIPA) and poly(propylene glycol) bis(2-aminopropyl ether) 2000. Then, its self-assembly in aqueous solution is investigated through direct hydration. The size and morphology of the self-assemblies is investigated by transmission electron microscope (TEM), scanning electron microscope (SEM), atomic force microscope (AFM), and optical microscope (OM) measurements. The result shows that the as-prepared polyamide first self-assembles to thick walled tubes, then these tubes can gradually evolve to ultrathick wall microvesicles with an unusually thick membrane above 330 nm. Both the transition pathway and the mechanism are investigated in micromicroscopy. Most importantly, the microvesicles show great thermal and chemical stability. The novel superstable self-assembly structures as well as the transition mechanism presented here offer a promising perspective for the application in the scope of the biological membrane movements and nanoelectromechanics in medical devices.


Asunto(s)
Nylons
20.
BMC Musculoskelet Disord ; 22(1): 794, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34525991

RESUMEN

BACKGROUND: In scoliosis corrective surgery, total blood loss is composed of visible blood loss, including intraoperative haemorrhage and drainage, and hidden blood loss in which blood extravasates into the tissues and accumulates in the surgical field. The purpose of this study was to investigate hidden blood loss (HBL) and its potential risk factors in adolescent idiopathic scoliosis patients undergoing posterior spinal fusion surgery and elucidate the influence of HBL on the necessity for postoperative blood transfusion. METHODS: We retrospectively studied adolescent idiopathic scoliosis patients undergoing posterior spine fusion for adolescent idiopathic scoliosis from January 2014 to December 2018 at our hospital. The patients' demographics, blood loss-related parameters, surgeries and blood loss data were extracted. The association between patient characteristics and HBL was analyzed by Pearson or Spearman correlation analyses. Multivariate linear regression analysis was used to determine independent risk factors associated with HBL. Binary logistic regression analysis was used to analyze the influence of HBL on the necessity for postoperative blood transfusion. RESULTS: A total of 765 patients, of whom 128 were male and 637 were female (age range 10-18 years), were included in this study. The mean volume of HBL was 693.5 ± 473.4 ml, accounting for 53.9 % of the total blood loss. The multivariate linear regression analysis revealed that preoperative Hct (p = 0.003) and allogeneic blood transfusion (p < 0.001) were independent risk factors for HBL, while tranexamic acid (p = 0.003) was negatively correlated with HBL. Binary logistic regression analysis showed that HBL > 850 ml (P < 0.001, OR: 8.845, 95 % CI: 5.806-13.290) was an independent risk factor for the necessity for postoperative blood transfusion. CONCLUSIONS: Substantial HBL occurred in adolescent idiopathic scoliosis patients undergoing posterior spinal fusion surgeries. Allogeneic blood transfusion and preoperative Hct were independent risk factors for HBL, while tranexamic acid was negatively related to HBL. HBL and its influencing factors should be considered when planning perioperative transfusion management. Patients with HBL greater than 850 ml should be closely monitored in cases of postoperative anaemia. LEVEL OF EVIDENCE: Level III.


Asunto(s)
Cifosis , Escoliosis , Fusión Vertebral , Adolescente , Pérdida de Sangre Quirúrgica , Niño , Femenino , Humanos , Masculino , Estudios Retrospectivos , Escoliosis/diagnóstico por imagen , Escoliosis/cirugía , Fusión Vertebral/efectos adversos
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