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1.
Nature ; 619(7970): 624-631, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37344596

RESUMEN

Loss of the Y chromosome (LOY) is observed in multiple cancer types, including 10-40% of bladder cancers1-6, but its clinical and biological significance is unknown. Here, using genomic and transcriptomic studies, we report that LOY correlates with poor prognoses in patients with bladder cancer. We performed in-depth studies of naturally occurring LOY mutant bladder cancer cells as well as those with targeted deletion of Y chromosome by CRISPR-Cas9. Y-positive (Y+) and Y-negative (Y-) tumours grew similarly in vitro, whereas Y- tumours were more aggressive than Y+ tumours in immune-competent hosts in a T cell-dependent manner. High-dimensional flow cytometric analyses demonstrated that Y- tumours promote striking dysfunction or exhaustion of CD8+ T cells in the tumour microenvironment. These findings were validated using single-nuclei RNA sequencing and spatial proteomic evaluation of human bladder cancers. Of note, compared with Y+ tumours, Y- tumours exhibited an increased response to anti-PD-1 immune checkpoint blockade therapy in both mice and patients with cancer. Together, these results demonstrate that cancer cells with LOY mutations alter T cell function, promoting T cell exhaustion and sensitizing them to PD-1-targeted immunotherapy. This work provides insights into the basic biology of LOY mutation and potential biomarkers for improving cancer immunotherapy.


Asunto(s)
Linfocitos T CD8-positivos , Deleción Cromosómica , Cromosomas Humanos Y , Escape del Tumor , Neoplasias de la Vejiga Urinaria , Animales , Humanos , Ratones , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Cromosomas Humanos Y/genética , Proteómica , Microambiente Tumoral/inmunología , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/inmunología , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/terapia , Escape del Tumor/genética , Escape del Tumor/inmunología , Perfilación de la Expresión Génica , Genómica , Pronóstico , Sistemas CRISPR-Cas , Edición Génica , Técnicas In Vitro , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Citometría de Flujo , Inmunoterapia
2.
Brief Bioinform ; 25(5)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39171986

RESUMEN

During the drug discovery and design process, the acid-base dissociation constant (pKa) of a molecule is critically emphasized due to its crucial role in influencing the ADMET (absorption, distribution, metabolism, excretion, and toxicity) properties and biological activity. However, the experimental determination of pKa values is often laborious and complex. Moreover, existing prediction methods exhibit limitations in both the quantity and quality of the training data, as well as in their capacity to handle the complex structural and physicochemical properties of compounds, consequently impeding accuracy and generalization. Therefore, developing a method that can quickly and accurately predict molecular pKa values will to some extent help the structural modification of molecules, and thus assist the development process of new drugs. In this study, we developed a cutting-edge pKa prediction model named GR-pKa (Graph Retention pKa), leveraging a message-passing neural network and employing a multi-fidelity learning strategy to accurately predict molecular pKa values. The GR-pKa model incorporates five quantum mechanical properties related to molecular thermodynamics and dynamics as key features to characterize molecules. Notably, we originally introduced the novel retention mechanism into the message-passing phase, which significantly improves the model's ability to capture and update molecular information. Our GR-pKa model outperforms several state-of-the-art models in predicting macro-pKa values, achieving impressive results with a low mean absolute error of 0.490 and root mean square error of 0.588, and a high R2 of 0.937 on the SAMPL7 dataset.


Asunto(s)
Redes Neurales de la Computación , Termodinámica , Descubrimiento de Drogas/métodos
3.
Brief Bioinform ; 25(1)2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-38145946

RESUMEN

Metabolic plasticity enables cancer cells to meet divergent demands for tumorigenesis, metastasis and drug resistance. Landscape analysis of tumor metabolic plasticity spanning different cancer types, in particular, metabolic crosstalk within cell subpopulations, remains scarce. Therefore, we proposed a new in-silico framework, termed as MMP3C (Modeling Metabolic Plasticity by Pathway Pairwise Comparison), to depict tumor metabolic plasticity based on transcriptome data. Next, we performed an extensive metabo-plastic analysis of over 6000 tumors comprising 13 cancer types. The metabolic plasticity within distinct cell subpopulations, particularly interplay with tumor microenvironment, were explored at single-cell resolution. Ultimately, the metabo-plastic events were screened out for multiple clinical applications via machine learning methods. The pilot research indicated that 6 out of 13 cancer types exhibited signs of the Warburg effect, implying its high reliability and robustness. Across 13 cancer types, high metabolic organized heterogeneity was found, and four metabo-plastic subtypes were determined, which link to distinct immune and metabolism patterns impacting prognosis. Moreover, MMP3C analysis of approximately 60 000 single cells of eight breast cancer patients unveiled several metabo-plastic events correlated to tumorigenesis, metastasis and immunosuppression. Notably, the metabolic features screened out by MMP3C are potential biomarkers for diagnosis, tumor classification and prognosis. MMP3C is a practical cross-platform tool to capture tumor metabolic plasticity, and our study unveiled a core set of metabo-plastic pairs among diverse cancer types, which provides bases toward improving response and overcoming resistance in cancer therapy.


Asunto(s)
Neoplasias de la Mama , Transcriptoma , Humanos , Femenino , Reproducibilidad de los Resultados , Carcinogénesis , Transformación Celular Neoplásica , Microambiente Tumoral
5.
Nature ; 573(7772): 96-101, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31462779

RESUMEN

The viscoelasticity of the crosslinked semiflexible polymer networks-such as the internal cytoskeleton and the extracellular matrix-that provide shape and mechanical resistance against deformation is assumed to dominate tissue mechanics. However, the mechanical responses of soft tissues and semiflexible polymer gels differ in many respects. Tissues stiffen in compression but not in extension1-5, whereas semiflexible polymer networks soften in compression and stiffen in extension6,7. In shear deformation, semiflexible polymer gels stiffen with increasing strain, but tissues do not1-8. Here we use multiple experimental systems and a theoretical model to show that a combination of nonlinear polymer network elasticity and particle (cell) inclusions is essential to mimic tissue mechanics that cannot be reproduced by either biopolymer networks or colloidal particle systems alone. Tissue rheology emerges from an interplay between strain-stiffening polymer networks and volume-conserving cells within them. Polymer networks that soften in compression but stiffen in extension can be converted to materials that stiffen in compression but not in extension by including within the network either cells or inert particles to restrict the relaxation modes of the fibrous networks that surround them. Particle inclusions also suppress stiffening in shear deformation; when the particle volume fraction is low, they have little effect on the elasticity of the polymer networks. However, as the particles become more closely packed, the material switches from compression softening to compression stiffening. The emergence of an elastic response in these composite materials has implications for how tissue stiffness is altered in disease and can lead to cellular dysfunction9-11. Additionally, the findings could be used in the design of biomaterials with physiologically relevant mechanical properties.


Asunto(s)
Fenómenos Biomecánicos , Biopolímeros/química , Recuento de Células , Matriz Extracelular/metabolismo , Fibrina/metabolismo , Tejido Adiposo/citología , Tejido Adiposo/metabolismo , Animales , Coagulación Sanguínea , Línea Celular , Elasticidad , Eritrocitos/citología , Fibrina/química , Fibroblastos/citología , Glioma/patología , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Modelos Biológicos , Ratas , Ratas Sprague-Dawley , Reología
6.
Proc Natl Acad Sci U S A ; 119(15): e2116718119, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35394874

RESUMEN

Cells can sense and respond to mechanical forces in fibrous extracellular matrices (ECMs) over distances much greater than their size. This phenomenon, termed long-range force transmission, is enabled by the realignment (buckling) of collagen fibers along directions where the forces are tensile (compressive). However, whether other key structural components of the ECM, in particular glycosaminoglycans (GAGs), can affect the efficiency of cellular force transmission remains unclear. Here we developed a theoretical model of force transmission in collagen networks with interpenetrating GAGs, capturing the competition between tension-driven collagen fiber alignment and the swelling pressure induced by GAGs. Using this model, we show that the swelling pressure provided by GAGs increases the stiffness of the collagen network by stretching the fibers in an isotropic manner. We found that the GAG-induced swelling pressure can help collagen fibers resist buckling as the cells exert contractile forces. This mechanism impedes the alignment of collagen fibers and decreases long-range cellular mechanical communication. We experimentally validated the theoretical predictions by comparing the intensity of collagen fiber alignment between cellular spheroids cultured on collagen gels versus collagen­GAG cogels. We found significantly lower intensities of aligned collagen in collagen­GAG cogels, consistent with the prediction that GAGs can prevent collagen fiber alignment. The role of GAGs in modulating force transmission uncovered in this work can be extended to understand pathological processes such as the formation of fibrotic scars and cancer metastasis, where cells communicate in the presence of abnormally high concentrations of GAGs.


Asunto(s)
Comunicación Celular , Matriz Extracelular , Glicosaminoglicanos , Fenómenos Biomecánicos , Fenómenos Fisiológicos Celulares , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Fibrosis , Glicosaminoglicanos/metabolismo , Humanos , Neoplasias
7.
BMC Genomics ; 25(1): 67, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233751

RESUMEN

BACKGROUND: Rye (Secale cereale), one of the drought and cold-tolerant crops, is an important component of the Triticae Dumortier family of Gramineae plants. Basic helix-loop-helix (bHLH), an important family of transcription factors, has played pivotal roles in regulating numerous intriguing biological processes in plant development and abiotic stress responses. However, no systemic analysis of the bHLH transcription factor family has yet been reported in rye. RESULTS: In this study, 220 bHLH genes in S. cereale (ScbHLHs) were identified and named based on the chromosomal location. The evolutionary relationships, classifications, gene structures, motif compositions, chromosome localization, and gene replication events in these ScbHLH genes are systematically analyzed. These 220 ScbHLH members are divided into 21 subfamilies and one unclassified gene. Throughout evolution, the subfamilies 5, 9, and 18 may have experienced stronger expansion. The segmental duplications may have contributed significantly to the expansion of the bHLH family. To systematically analyze the evolutionary relationships of the bHLH family in different plants, we constructed six comparative genomic maps of homologous genes between rye and different representative monocotyledonous and dicotyledonous plants. Finally, the gene expression response characteristics of 22 ScbHLH genes in various biological processes and stress responses were analyzed. Some candidate genes, such as ScbHLH11, ScbHLH48, and ScbHLH172, related to tissue developments and environmental stresses were screened. CONCLUSIONS: The results indicate that these ScbHLH genes exhibit characteristic expression in different tissues, grain development stages, and stress treatments. These findings provided a basis for a comprehensive understanding of the bHLH family in rye.


Asunto(s)
Genoma de Planta , Secale , Secale/genética , Filogenia , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/química , Factores de Transcripción/metabolismo , Regulación de la Expresión Génica de las Plantas
8.
J Am Chem Soc ; 146(19): 13326-13335, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38693621

RESUMEN

A key challenge in the search of new materials capable of singlet fission (SF) arises from the primary energy conservation criterion, i.e., the energy of the triplet exciton has to be half that of the singlet (E(S1) ≥ 2E(T1)), which excludes most photostable organic materials from consideration and confines the design strategy to materials with low energy triplet states. One potential way to overcome this energy requirement and improve the triplet energy is to enable a SF channel from higher energy ("hot") excitonic states (Sn) in a process called activated SF. Herein, we demonstrate that efficient activated SF is achieved in a rylene imide-based derivative acenaphth[l, 2-a]acenaphthylene diimide (AADI). This process is enabled by an increase in the energy gap to greater than 1.0 eV between the S3 and S1 states due to the incorporation of an antiaromatic pentalene unit, which leads to the emergence of anti-Kasha properties in the isolated molecule. Transient spectroscopy studies show that AADI undergoes ultrafast SF from higher singlet excited states in thin film, with excitation wavelength-dependent SF yields. The SF yield of ∼200% is observed upon higher energy excitation, and long-lived free triplets persist on the µs time scale suggesting that AADI can be used in SF-enhanced devices. Our results suggest that enlarging the Sn-S1 energy gap is an effective way to turn on the activated SF channel and shed light on the development of novel, stable SF materials with high triplet energies.

9.
Breast Cancer Res ; 26(1): 70, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654332

RESUMEN

BACKGROUND: Basal-like breast cancer (BLBC) is the most aggressive subtype of breast cancer due to its aggressive characteristics and lack of effective therapeutics. However, the mechanism underlying its aggressiveness remains largely unclear. S-adenosylmethionine decarboxylase proenzyme (AMD1) overexpression occurs specifically in BLBC. Here, we explored the potential molecular mechanisms and functions of AMD1 promoting the aggressiveness of BLBC. METHODS: The potential effects of AMD1 on breast cancer cells were tested by western blotting, colony formation, cell proliferation assay, migration and invasion assay. The spermidine level was determined by high performance liquid chromatography. The methylation status of CpG sites within the AMD1 promoter was evaluated by bisulfite sequencing PCR. We elucidated the relationship between AMD1 and Sox10 by ChIP assays and quantitative real-time PCR. The effect of AMD1 expression on breast cancer cells was evaluated by in vitro and in vivo tumorigenesis model. RESULTS: In this study, we showed that AMD1 expression was remarkably elevated in BLBC. AMD1 copy number amplification, hypomethylation of AMD1 promoter and transcription activity of Sox10 contributed to the overexpression of AMD1 in BLBC. AMD1 overexpression enhanced spermidine production, which enhanced eIF5A hypusination, activating translation of TCF4 with multiple conserved Pro-Pro motifs. Our studies showed that AMD1-mediated metabolic system of polyamine in BLBC cells promoted tumor cell proliferation and tumor growth. Clinically, elevated expression of AMD1 was correlated with high grade, metastasis and poor survival, indicating poor prognosis of breast cancer patients. CONCLUSION: Our work reveals the critical association of AMD1-mediated spermidine-eIF5A hypusination-TCF4 axis with BLBC aggressiveness, indicating potential prognostic indicators and therapeutic targets for BLBC.


Asunto(s)
Neoplasias de la Mama , Proliferación Celular , Factor 5A Eucariótico de Iniciación de Traducción , Regulación Neoplásica de la Expresión Génica , Lisina/análogos & derivados , Factores de Iniciación de Péptidos , Proteínas de Unión al ARN , Espermidina , Factor de Transcripción 4 , Humanos , Femenino , Neoplasias de la Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Factores de Iniciación de Péptidos/metabolismo , Factores de Iniciación de Péptidos/genética , Ratones , Animales , Espermidina/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Factor de Transcripción 4/metabolismo , Factor de Transcripción 4/genética , Línea Celular Tumoral , Regiones Promotoras Genéticas , Adenosilmetionina Descarboxilasa/metabolismo , Adenosilmetionina Descarboxilasa/genética , Movimiento Celular/genética , Metilación de ADN , Pronóstico , Factores de Transcripción SOXE/metabolismo , Factores de Transcripción SOXE/genética
10.
Small ; : e2405276, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39092684

RESUMEN

Halide perovskites are of great interest due to their exceptional optical and optoelectronic properties. However, thermal conductivity of many halide perovskites remains unexplored. In this study, an ultralow lattice thermal conductivity κL (0.24 W m-1 K-1 at 300 K) is reported and its weak temperature dependence (≈T-0.27) in an all-inorganic vacancy-ordered halide perovskite, Cs3Bi2Br9. The intrinsically ultralow κL can be attributed to the soft low-lying phonon modes with strong anharmonicity, which have been revealed by combining experimental heat capacity and Raman spectroscopy measurements, and first-principles calculations. It is shown that the highly anharmonic phonons originate from the Bi 6s2 lone pair expression with antibonding states of Bi 6s and Br 4p orbitals driven by the dynamic BiBr6 octahedral distortion. Theoretical calculations reveal that these low-energy phonons are mostly contributed by large Br motions induced dynamic distortion of BiBr6 octahedra and large Cs rattling motions, verified by the synchrotron X-ray pair distribution function analysis. In addition, the weak temperature dependence of κL can be traced to the wave-like tunneling of phonons, induced by the low-lying phonon modes. This work reveals the strong anharmonicity and wave-like tunneling of low-energy phonons for designing efficient vacancy-ordered halide perovskites with intrinsically low κL.

11.
Phys Rev Lett ; 133(3): 036003, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39094159

RESUMEN

This work reports on the emergence of quantum Griffiths singularity (QGS) associated with the magnetic field induced superconductor-metal transition (SMT) in unconventional Nd_{0.8}Sr_{0.2}NiO_{2} infinite layer superconducting thin films. The system manifests isotropic SMT features under both in-plane and perpendicular magnetic fields. Importantly, after scaling analysis of the isothermal magnetoresistance curves, the obtained effective dynamic critical exponents demonstrate divergent behavior when approaching the zero-temperature critical point B_{c}^{*}, identifying the QGS characteristics. Moreover, the quantum fluctuation associated with the QGS can quantitatively explain the upturn of the upper critical field around zero temperature for both the in-plane and perpendicular magnetic fields in the phase boundary of SMT. These properties indicate that the QGS in the Nd_{0.8}Sr_{0.2}NiO_{2} superconducting thin film is isotropic. Moreover, a higher magnetic field gives rise to a metallic state with the resistance-temperature relation R(T) exhibiting lnT dependence among the 2-10 K range and T^{2} dependence of resistance below 1.5 K, which is significant evidence of Kondo scattering. The interplay between isotropic QGS and Kondo scattering in the unconventional Nd_{0.8}Sr_{0.2}NiO_{2} superconductor can illustrate the important role of rare region in QGS and help to uncover the exotic superconductivity mechanism in this system.

12.
Reprod Biol Endocrinol ; 22(1): 88, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080633

RESUMEN

OBJECTIVE: The objective of this retrospective cohort study is to investigate the impact of monitoring serum estradiol (E2) levels before progesterone administration within hormone replacement therapy (HRT) on pregnancy outcomes in women undergoing frozen-thawed embryo transfer (FET). METHODS: Analyzed HRT-FET cycles conducted at a reproductive center from 2017 to 2022. Serum E2 levels were measured prior to progesterone administration. Multivariate stratified and logistic regression analyses were performed on 26,194 patients grouped according to terciles of serum E2 levels before progesterone administration. RESULTS: The clinical pregnancy rate (CPR) and live birth rate (LBR) exhibited a gradual decline with increasing serum E2 levels across the three E2 groups. Even after controlling for potential confounders, including female age, body mass index, infertility diagnosis, cycle category, number of embryos transferred, fertilization method, indication for infertility, and endometrial thickness, both CPR and LBR persistently showed a gradual decrease as serum E2 levels increased within the three E2 groups. The same results were obtained by multivariate logistic regression analysis. CONCLUSIONS: This large retrospective study indicates that elevated serum E2 levels before progesterone administration during HRT-FET cycles are associated with reduced CPR and LBR post-embryo transfer. Therefore, it is advisable to monitor serum E2 levels and adjust treatment strategies accordingly to maximize patient outcomes.


Asunto(s)
Criopreservación , Transferencia de Embrión , Estradiol , Terapia de Reemplazo de Hormonas , Resultado del Embarazo , Índice de Embarazo , Progesterona , Humanos , Femenino , Embarazo , Transferencia de Embrión/métodos , Estradiol/sangre , Progesterona/sangre , Estudios Retrospectivos , Adulto , Terapia de Reemplazo de Hormonas/métodos , Resultado del Embarazo/epidemiología , Fertilización In Vitro/métodos , Nacimiento Vivo/epidemiología
13.
Pediatr Res ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961163

RESUMEN

BACKGROUND: We sought to evaluate renal stiffness in children with hematuria and/or proteinuria using shear wave elastography (SWE) and to investigate the clinical value of renal stiffness in children with hematuria and/or proteinuria. METHODS: According to the results of urinary occult blood and urinary protein tests, 349 pediatric patients were categorized into one of four groups: pure hematuria (HU), pure proteinuria (PU), concomitant hematuria and proteinuria (HUPU), or control (non-HUPU). Patient demographic data, laboratory test results, and renal ultrasound data were collected. RESULTS: There were significant differences in cortical/medullary elasticity among the four groups (the most sensitive cutoff value between HU and PU was 1.72) (P < 0.05). We found that hematuria and proteinuria interacted with renal cortical elasticity (P < 0.05) but that hematuria and proteinuria did not interact with renal medullary elasticity or cortical/medullary elasticity (P > 0.05). Renal elasticity values correlated with sex, age, body surface area, body mass index, qualitative urinary protein, urine N-acetyl-ß-D-glucosaminidase, 24-hour urinary protein quantity, renal volume, and renal cortical thickness (P < 0.05). CONCLUSIONS: SWE can be used to detect changes in renal stiffness in children with hematuria and/or proteinuria. SWE is beneficial for the early detection of glomerular disease in children with abnormal urine test results. IMPACT: This study evaluated the utility of shear wave elastography for the assessment of renal elasticity in pediatric patients presenting with hematuria and/or proteinuria. Children with pure proteinuria had significantly higher renal cortical/medullary elasticity values than those with pure hematuria. An interaction effect between hematuria and proteinuria on renal cortical stiffness was observed. Shear wave elastography can be used as a tool to assess early renal injury in children with urinalysis abnormalities.

14.
J Org Chem ; 89(16): 11671-11681, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39096319

RESUMEN

2-Alkyl chromanone scaffold has become prominent in pharmaceuticals and natural compounds. Consequently, devising robust strategies for synthesizing 2-alkyl chromanones remains crucial. Here, multicomponent reactions were employed to synthesize 2-alkyl chromanones containing an oxazole moiety using 3-formylchromones, amines, and N-propargylamides as reactants. This method utilizes readily available feedstocks with a catalytic amount of Zn(OTf)2 and exhibits an impressive substrate scope compared to existing methods. Importantly, the synthesized compounds demonstrated highly selective anticancer activity against the DU145 cell line.


Asunto(s)
Antineoplásicos , Cromonas , Ácidos de Lewis , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Humanos , Cromonas/química , Cromonas/farmacología , Cromonas/síntesis química , Línea Celular Tumoral , Ácidos de Lewis/química , Estructura Molecular , Ensayos de Selección de Medicamentos Antitumorales , Proliferación Celular/efectos de los fármacos , Catálisis , Relación Estructura-Actividad
15.
Inorg Chem ; 63(27): 12572-12581, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38924490

RESUMEN

The kinetics of electrocatalytic reactions are closely related to the number and intrinsic activity of the active sites. Open active sites offer easy access to the substrate and allow for efficient desorption and diffusion of reaction products without significant hindrance. Metal-organic frameworks (MOFs) with open active sites show great potential in this context. To increase the density of active sites, trimesic acid was utilized as a ligand to anchor more Ni sites and in situ construct the nickel foam-loaded Ni-based trimesic MOF electrocatalyst (Ni-TMA-MOF/NF). When tested as an electrocatalyst for benzyl alcohol oxidation, Ni-TMA-MOF/NF exhibited lower overpotential and superior durability compared to Ni foam-loaded Ni-based terephthalic MOF electrocatalyst (Ni-PTA-MOF/NF) and Ni(OH)2 nanosheet array (Ni(OH)2/NF). Ni-TMA-MOF/NF required only a low potential of 1.65 V to achieve a high current density of 400 mA cm-2. Even after 40000 s of electrocatalytic oxidation at 1.5 V, Ni-TMA-MOF/NF maintained a current density of 175 mA cm-2 with ∼68% retention, showing its potential for benzyl alcohol oxidation. Through a combination of experimental and theoretical investigations, it was found that Ni-TMA-MOF/NF displayed superior electrocatalytic activity due to an optimized electron structure with high-valence Ni species and a high density of active sites, enabling long-term stable operation at high current densities. This study provides a new perspective on the design of electrocatalysts for benzyl alcohol oxidation.

16.
Macromol Rapid Commun ; 45(1): e2300241, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37548255

RESUMEN

Singlet fission (SF) is a spin-allowed process in which a higher-energy singlet exciton is converted into two lower-energy triplet excitons via a triplet pair intermediate state. Implementing SF in photovoltaic devices holds the potential to exceed the Shockley-Queisser limit of conventional single-junction solar cells. Although great progress has been made in exploiting the underlying mechanism of SF over the past decades, the scope of materials capable of SF, particularly polymeric materials, remains poor. SF-capable polymer is one of the most potential candidates in the implementation of SF into devices due to their distinct superiorities in flexibility, solution processability and self-assembly behavior. Notably, recent advancements have demonstrated high-performance SF in isolated donor-acceptor (D-A) copolymer chains. This review provides an overview of recent progress in the development of SF-capable polymeric materials, with a significant focus on elucidating the mechanisms of SF in polymers and optimizing the design strategies for SF-capable polymers. Additionally, the paper discusses the challenges encountered in this field and presents future perspectives. It is expected that this comprehensive review will offer valuable insights into the design of novel SF-capable polymeric materials, further advancing the potential for SF implementation in photovoltaic devices.


Asunto(s)
Polímeros
17.
Environ Res ; 248: 118305, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38307183

RESUMEN

Chlorinated polyfluorinated ether sulfonate (F-53B), a substitute of perfluorooctane sulfonic acid (PFOS), has attracted significant attention for its link to hepatotoxicity and enterotoxicity. Nevertheless, the underlying mechanisms of F-53B-induced enterohepatic toxicity remain incompletely understood. This study aimed to explore the role of F-53B exposure on enterohepatic injury based on the gut microbiota, pathological and molecular analysis in mice. Here, we exposed C57BL/6 mice to F-53B (0, 4, 40, and 400 µg/L) for 28 days. Our findings revealed a significant accumulation of F-53B in the liver, followed by small intestines, and feces. In addition, F-53B induced pathological collagen fiber deposition and lipoid degeneration, up-regulated the expression of fatty acid ß-oxidation-related genes (PPARα and PPARγ, etc), while simultaneously down-regulating pro-inflammatory genes (Nlrp3, IL-1ß, and Mcp1) in the liver. Meanwhile, F-53B induced ileal mucosal barrier damage, and an up-regulation of pro-inflammatory genes and mucosal barrier-related genes (Muc1, Muc2, Claudin1, Occludin, Mct1, and ZO-1) in the ileum. Importantly, F-53B distinctly altered gut microbiota compositions by increasing the abundance of Akkermansia and decreasing the abundance of Prevotellaceae_NK3B31_group in the feces. F-53B-altered microbiota compositions were significantly associated with genes related to fatty acid ß-oxidation, inflammation, and mucosal barrier. In summary, our results demonstrate that F-53B is capable of inducing hepatic injury, ileitis, and gut microbiota dysbiosis in mice, and the gut microbiota dysbiosis may play an important role in the F-53B-induced enterohepatic toxicity.


Asunto(s)
Microbioma Gastrointestinal , Ileítis , Ratones , Animales , Disbiosis , Pez Cebra/metabolismo , Ratones Endogámicos C57BL , Hígado , Ácidos Grasos/metabolismo
18.
J Chem Phys ; 160(16)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38666791

RESUMEN

Photoinduced symmetry-breaking charge separation (SB-CS) has been extensively observed in various oligomers and aggregates, which holds great potential for robust artificial solar energy conversion systems. It attaches great importance to the precise manipulation of interchromophore electronic coupling in realizing efficient SB-CS. The emerging studies on SB-CS suggested that it could be realized in null-excitonic aggregates, and a long-lived SB-CS state was observed, which offers an advanced platform and has gathered immense attention in the SB-CS field. Here, we unveiled the null-exciton coupling induced ultrafast SB-CS in a rigid polycyclic aromatic hydrocarbon framework, triperyleno[3,3,3]propellane triimides (TPPTI), in which three chromophores were attached through a nonconjugated bridge. Through a combination of theoretical calculations and steady-state absorption results, we demonstrated that this nonconjugated TPPTI possesses negligible exciton coupling. Increased solvent polarity was found to significantly enhance state mixing between local excited and charge transfer states. Using transient absorption spectroscopy, ultrafast SB-CS was observed in highly polar dimethylformamide, facilitated by a selective hole-transfer coupling and a favorable charge separation free energy (ΔGCS). Additionally, the rate ratio between SB-CS and charge recombination was at least high to 1800 in dimethylformamide. This investigation provides profound insights into the role of null-exciton coupling in dominating ultrafast SB-CS in multichromophoric systems.

19.
Differentiation ; 131: 82-88, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37178555

RESUMEN

The development of the hyoid bone is a complex process that involves the coordination of multiple signaling pathways. Previous studies have demonstrated that disruption of the hedgehog pathway in mice results in a series of structural malformations. However, the specific role and critical period of the hedgehog pathway in the early development of the hyoid bone have not been thoroughly characterized. In this study, we treated pregnant ICR mice with the hedgehog pathway inhibitor vismodegib by oral gavage in order to establish a model of hyoid bone dysplasia. Our results indicate that administration of vismodegib at embryonic days 11.5 (E11.5) and E12.5 resulted in the development of hyoid bone dysplasia. We were able to define the critical periods for the induction of hyoid bone deformity through the use of a meticulous temporal resolution. Our findings suggest that the hedgehog pathway plays a crucial role in the early development of the hyoid bone. Additionally, our research has established a novel and easily established mouse model of synostosis in the hyoid bone using a commercially available pathway-selective inhibitor.


Asunto(s)
Enfermedades del Desarrollo Óseo , Proteínas Hedgehog , Femenino , Embarazo , Ratones , Animales , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Hueso Hioides/metabolismo , Ratones Endogámicos ICR , Desarrollo Embrionario
20.
Ecotoxicol Environ Saf ; 281: 116659, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38964060

RESUMEN

Chronic Kidney Disease (CKD), closely linked to environmental factors, poses a significant public health challenge. This study, based on 529 triple-repeated measures from key national environmental pollution area and multiple gene-related public databases, employs various epidemiological and bioinformatics models to assess the impact of combined heavy metal exposure (Chromium [Cr], Cadmium [Cd], and Lead [Pb]) on early renal injury and CKD in the elderly. Introducing the novel Enviro-Target Mendelian Randomization method, our research explores the causal relationship between metals and CKD. The findings indicate a positive correlation between increased levels of metal and renal injury, with combined exposure caused renal damage more significantly than individual exposure. The study reveals that metals primarily influence CKD development through oxidative stress and metal ion resistance pathways, focusing on three related genes (SOD2, MPO, NQO1) and a transcription factor (NFE2L2). Metals were found to regulate oxidative stress levels in the body by increasing the expression of SOD2, MPO, NQO1, and decreasing NFE2L2, leading to CKD onset. Our research establishes a new causal inference framework linking environmental pollutants-pathways-genes-CKD, assessing the impact and mechanisms of metal exposure on CKD. Future studies with more extensive in vitro evidence and larger population are needed to validate.


Asunto(s)
Cadmio , Contaminantes Ambientales , Análisis de la Aleatorización Mendeliana , Metales Pesados , Estrés Oxidativo , Insuficiencia Renal Crónica , Humanos , Metales Pesados/toxicidad , Insuficiencia Renal Crónica/inducido químicamente , Insuficiencia Renal Crónica/epidemiología , Estrés Oxidativo/efectos de los fármacos , Anciano , Cadmio/toxicidad , Contaminantes Ambientales/toxicidad , Plomo/toxicidad , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa/genética , NAD(P)H Deshidrogenasa (Quinona)/genética , Factor 2 Relacionado con NF-E2/genética , Exposición a Riesgos Ambientales/efectos adversos , Masculino , Femenino , Cromo/toxicidad , Riñón/efectos de los fármacos
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