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1.
Cell Death Dis ; 15(7): 485, 2024 Jul 06.
Article in English | MEDLINE | ID: mdl-38971772

ABSTRACT

The discovery of novel oncotargets for glioma is of immense significance. We here explored the expression patterns, biological functions, and underlying mechanisms associated with ORC6 (origin recognition complex 6) in glioma. Through the bioinformatics analyses, we found a significant increase in ORC6 expression within human glioma tissues, correlating with poorer overall survival, higher tumor grade, and wild-type isocitrate dehydrogenase status. Additionally, ORC6 overexpression is detected in glioma tissues obtained from locally-treated patients and across various primary/established glioma cells. Further bioinformatics scrutiny revealed that genes co-expressed with ORC6 are enriched in multiple signaling cascades linked to cancer. In primary and immortalized (A172) glioma cells, depleting ORC6 using specific shRNA or Cas9-sgRNA knockout (KO) significantly decreased cell viability and proliferation, disrupted cell cycle progression and mobility, and triggered apoptosis. Conversely, enhancing ORC6 expression via a lentiviral construct augmented malignant behaviors in human glioma cells. ORC6 emerged as a crucial regulator for the expression of key oncogenic genes, including Cyclin A2, Cyclin B2, and DNA topoisomerase II (TOP2A), within glioma cells. Silencing or KO of ORC6 reduced the mRNA and protein levels of these genes, while overexpression of ORC6 increased their expression in primary glioma cells. Bioinformatics analyses further identified RBPJ as a potential transcription factor of ORC6. RBPJ shRNA decreased ORC6 expression in primary glioma cells, while its overexpression increased it. Additionally, significantly enhanced binding between the RBPJ protein and the proposed ORC6 promoter region was detected in glioma tissues and cells. In vivo experiments demonstrated a significant reduction in the growth of patient-derived glioma xenografts in the mouse brain subsequent to ORC6 KO. ORC6 depletion, inhibited proliferation, decreased expression of Cyclin A2/B2/TOP2A, and increased apoptosis were detected within these ORC6 KO intracranial glioma xenografts. Altogether, RBPJ-driven ORC6 overexpression promotes glioma cell growth, underscoring its significance as a promising therapeutic target.


Subject(s)
Cell Proliferation , Gene Expression Regulation, Neoplastic , Glioma , Origin Recognition Complex , Animals , Humans , Male , Mice , Apoptosis/genetics , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Brain Neoplasms/metabolism , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Cyclin A2/metabolism , Cyclin A2/genetics , Cyclin B2/metabolism , Cyclin B2/genetics , DNA Topoisomerases, Type II/metabolism , DNA Topoisomerases, Type II/genetics , Glioma/genetics , Glioma/pathology , Glioma/metabolism , Mice, Nude , Origin Recognition Complex/metabolism , Origin Recognition Complex/genetics
2.
Angew Chem Int Ed Engl ; : e202410046, 2024 Jul 20.
Article in English | MEDLINE | ID: mdl-39032152

ABSTRACT

Fast-charging capability and calendar life are critical metrics in rechargeable batteries, especially in silicon-based batteries that are susceptible to sluggish Li+ desolvation kinetics and HF-induced corrosion. No existing electrolyte simultaneously tackles both these pivotal challenges. Here we report a microscopically heterogeneous covalent organic nanosheet (CON) colloid electrolyte for extremely fast-charging and long-calendar-life Si-based lithium-ion batteries. Theoretical calculations and operando Raman spectroscopy reveal the fundamental mechanism of the multiscale noncovalent interaction, which involves the mesoscopic CON attenuating the microscopic Li+-solvent coordination, thereby expediting the Li+ desolvation kinetics. This electrolyte design enables extremely fast-charging capabilities of the full cell, both at 8C (83.1% state of charge) and 10C (81.3% state of charge). Remarkably, the colloid electrolyte demonstrates record-breaking cycling performance at 10C (capacity retention of 92.39% after 400 cycles). Moreover, benefiting from the robust adsorption capability of mesoporous CON towards HF and water, a notable improvement is observed in the calendar life of the full cell. This study highlights the role of microscopically heterogeneous colloid electrolytes in enhancing the fast-charging capability and calendar life of Si-based Li-ion batteries. Our work offers fresh perspectives on electrolyte design with multiscale interactions, providing insightful guidance for the development of alkali-ion/metal batteries operating under harsh environments.

3.
BMC Geriatr ; 24(1): 595, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38992589

ABSTRACT

BACKGROUND: Atypical chronic myeloid leukemia (aCML) is a highly aggressive type of blood cancer that falls under the category of myelodysplastic/myeloproliferative neoplasms (MDS/MPN). In the fifth edition of the WHO classification of tumors, this category has been renamed MDS/MPN with neutrophilia. Although eosinophilia is commonly observed in blood cancers, it is rarely seen in aCML. CASE PRESENTATION: This study presents a case of aCML that was diagnosed six years after the patient developed eosinophilia. The patient had undergone tests to rule out other primary and secondary diseases, but the eosinophilia remained unexplained. Treatment with corticosteroids and hydroxyurea had proven ineffective. Six years later, the patient experienced an increase in white blood cells, primarily neutrophils. After ruling out other possible diagnoses, a combination of morphologic and molecular genetic findings led to the diagnosis of aCML. The patient responded well to treatment with azacitidine. CONCLUSIONS: This study summarizes the current state of aCML diagnosis and management and discusses the possible connection between eosinophilia and aCML.


Subject(s)
Eosinophilia , Humans , Eosinophilia/diagnosis , Eosinophilia/complications , Male , Leukemia, Myeloid, Chronic, Atypical, BCR-ABL Negative/diagnosis , Leukemia, Myeloid, Chronic, Atypical, BCR-ABL Negative/drug therapy , Time Factors , Aged
4.
Nat Commun ; 15(1): 5736, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38982049

ABSTRACT

Excessive exercise is an etiological factor of intervertebral disc degeneration (IVDD). Engineered extracellular vesicles (EVs) exhibit excellent therapeutic potential for disease-modifying treatments. Herein, we fabricate an exercise self-powered triboelectric-responsive microneedle (MN) assay with the sustainable release of optogenetically engineered EVs for IVDD repair. Mechanically, exercise promotes cytosolic DNA sensing-mediated inflammatory activation in senescent nucleus pulposus (NP) cells (the master cell population for IVD homeostasis maintenance), which accelerates IVDD. TREX1 serves as a crucial nuclease, and disassembly of TRAM1-TREX1 complex disrupts the subcellular localization of TREX1, triggering TREX1-dependent genomic DNA damage during NP cell senescence. Optogenetically engineered EVs deliver TRAM1 protein into senescent NP cells, which effectively reconstructs the elimination function of TREX1. Triboelectric nanogenerator (TENG) harvests mechanical energy and triggers the controllable release of engineered EVs. Notably, an optogenetically engineered EV-based targeting treatment strategy is used for the treatment of IVDD, showing promising clinical potential for the treatment of degeneration-associated disorders.


Subject(s)
Extracellular Vesicles , Intervertebral Disc Degeneration , Needles , Nucleus Pulposus , Optogenetics , Intervertebral Disc Degeneration/therapy , Intervertebral Disc Degeneration/metabolism , Extracellular Vesicles/metabolism , Animals , Nucleus Pulposus/metabolism , Optogenetics/methods , Optogenetics/instrumentation , Humans , Phosphoproteins/metabolism , Phosphoproteins/genetics , Cellular Senescence , Exodeoxyribonucleases/metabolism , Exodeoxyribonucleases/genetics , Rats , DNA Damage , Mice , Male , Disease Models, Animal , Rats, Sprague-Dawley
5.
Inorg Chem ; 63(28): 12764-12773, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38950312

ABSTRACT

Cobalt (Co)-based materials have been widely investigated as hopeful noble-metal-free alternatives for the oxygen evolution reaction (OER) in alkaline electrolytes, which is crucial for generating hydrogen by water electrolysis. Herein, cobalt-based telluride particles with good electronic conductivity as anodic electrocatalysts were prepared under vacuum by the solid-state strategy, which display remarkable activities toward the OER. Nickel (Ni) and iron (Fe) codoped cobalt telluride (NiFe-CoTe) exhibits an overpotential of 321 mV to achieve a current density of 10 mA cm-2 and a Tafel slope of 51.8 mV dec-1, outperforming the performances of CoTe, CoTe2, and IrO2. According to the DFT calculation, the adsorbed hydroxyl-assisted adsorbate evolution mechanism was proposed for the OER process of NiFe-CoTe, which reveals the synergetic effect toward OER induced by codoping of the Ni and Fe atoms. This work proposes a rational strategy to prepare cobalt-based tellurides as efficient OER catalysts in alkaline electrolytes, providing a new strategy to prepare and regulate metal-based tellurides for catalysis and beyond.

6.
Nat Plants ; 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-39014153

ABSTRACT

Heterochromatic condensates (chromocenters) are critical for maintaining the silencing of heterochromatin. It is therefore puzzling that the presence of chromocenters is variable across plant species. Here we reveal that variations in the plant heterochromatin protein ADCP1 confer a diversity in chromocenter formation via phase separation. ADCP1 physically interacts with the high mobility group protein HMGA to form a complex and mediates heterochromatin condensation by multivalent interactions. The loss of intrinsically disordered regions (IDRs) in ADCP1 homologues during evolution has led to the absence of prominent chromocenter formation in various plant species, and introduction of IDR-containing ADCP1 with HMGA promotes heterochromatin condensation and retrotransposon silencing. Moreover, plants in the Cucurbitaceae group have evolved an IDR-containing chimaera of ADCP1 and HMGA, which remarkably enables formation of chromocenters. Together, our work uncovers a coevolved mechanism of phase separation in packing heterochromatin and silencing retrotransposons.

7.
J Immunother Cancer ; 12(6)2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38925680

ABSTRACT

BACKGROUND: The majority of anti-programmed cell-death 1 (PD-1) monoclonal antibodies (mAbs) use S228P mutation IgG4 as the structural basis to avoid the activation of immune cells or complement. However, little attention has been paid to the Fc-Fc interactions between IgG4 and other IgG Fc fragments that could result in adverse effects. Fc-null IgG1 framework is a potential safer alternative to avoid the undesirable Fc-Fc interactions and Fc receptor binding derived effects observed with IgG4. This study provides a comprehensive evaluation of anti-PD-1 mAbs of these two frameworks. METHODS: Trastuzumab and rituximab (both IgG1), wildtype IgG1 and IgG4 were immobilized on nitrocellulose membranes, coated to microplates and biosensor chips, and bound to tumor cells as targets for Fc-Fc interactions. Wildtype IgG1 and IgG4, anti-PD-1 mAb nivolumab (IgG4 S228P), penpulimab (Fc-null IgG1), and tislelizumab (Fc-null IgG4 S228P-R409K) were assessed for their binding reactions to the immobilized IgG proteins and quantitative kinetic data were obtained. To evaluate the effects of the two anti-PD-1 mAbs on immune responses mediated by trastuzumab and rituximab in the context of combination therapy, we employed classic immune models for antibody-dependent cellular cytotoxicity, antibody-dependent cellular phagocytosis, and complement dependent cytotoxicity. Tumor-bearing mouse models, both wildtype and humanized, were used for in vivo investigation. Furthermore, we also examined the effects of IgG1 and IgG4 on diverse immune cell populations RESULTS: Experiments demonstrated that wildtype IgG4 and nivolumab bound to immobilized IgG through Fc-Fc interactions, diminishing antibody-dependent cell-mediated cytotoxicity and phagocytosis reactions. Quantitative analysis of kinetic parameters suggests that nivolumab and wildtype IgG4 exhibit comparable binding affinities to immobilized IgG1 in both non-denatured and denatured states. IgG4 exerted inhibitory effects on various immune cell types. Wildtype IgG4 and nivolumab both promoted tumor growth in wildtype mouse models. Conversely, wildtype IgG1, penpulimab, and tislelizumab did not show similar adverse effects. CONCLUSIONS: Fc-null IgG1 represents a safer choice for anti-PD-1 immunotherapies by avoiding both the adverse Fc-Fc interactions and Fc-related immune inhibitory effects of IgG4. Fc-null IgG4 S228P-R409K and Fc-null IgG1 displayed similar structural properties and benefits. This study contributes to the understanding of immunotherapy resistance and the advancement of safer immune therapies for cancer.


Subject(s)
Immunoglobulin G , Immunotherapy , Immunoglobulin G/immunology , Animals , Mice , Humans , Immunotherapy/methods , Immunoglobulin Fc Fragments/pharmacology , Female , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Programmed Cell Death 1 Receptor/metabolism
8.
Adv Mater ; : e2403961, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38830614

ABSTRACT

In recent years, conjugated polymers have received widespread attention due to their characteristic advantages of light weight, favorable solution processability, and structural modifiability. Among various conjugated polymers, fluorinated ones have developed rapidly to achieve high-performance n-type or ambipolar polymeric semiconductors. The uniqueness of fluorinated conjugated polymers contains the high coplanarity of their structures, lower frontier molecular orbital energy levels, and strong nonbonding interactions. In this review, first the fluorinated building blocks, including fluorinated benzene and thiophene rings, fluorinated B←N bridged units, and fluoroalkyl side chains are summarized. Subsequently, different synthetic methods of fluorinated conjugated polymers are described, with a special focus on their respective advantages and disadvantages. Then, with these numerous fluorinated structures and appropriate synthetic methods bear in mind, the properties and applications of the fluorinated conjugated polymers, such as cyclopentadithiophene-, amide-, and imide-based polymers, and B←N embedded polymers, are systematically discussed. The introduction of fluorine atoms can further enhance the electron-deficiency of the backbone, influencing the charge carrier transport performance. The promising fluorinated conjugated polymers are applied widely in organic field-effect transistors, organic solar cells, organic thermoelectric devices, and other organic opto-electric devices. Finally, the outlook on the challenges and future development of fluorinated conjugated polymers is systematically discussed.

9.
ACS Omega ; 9(24): 25429-25447, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38911814

ABSTRACT

Ultrawide bandgap (UWBG) semiconductors, including Ga2O3, diamond, Al x Ga1-x N/AlN, featuring bandgaps greater than 4.4 eV, hold significant promise for solar-blind ultraviolet photodetection, with applications spanning in environmental monitoring, chemical/biological analysis, industrial processes, and military technologies. Over recent decades, substantial strides in synthesizing high-quality UWBG semiconductors have facilitated the development of diverse high-performance solar-blind photodetectors (SBPDs). This review comprehensively examines recent advancements in UWBG semiconductor-based SBPDs across various device architectures, encompassing photoconductors, metal-semiconductor-metal photodetectors, Schottky photodiodes, p-n (p-i-n) photodiodes, phototransistors, etc., with a systematic introduction and discussion of their operational principles. The current state of device performance for SBPDs employing these UWBG semiconductors is evaluated across different device configurations. Finally, this review outlines key challenges to be addressed, aiming to steer future research endeavors in this critical domain.

11.
J Hazard Mater ; 475: 134920, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38880047

ABSTRACT

Dibutyl phthalate (DBP) as a plasticizer has been widely used in the processing of plastic products. Nevertheless, these DBP additives have the potential to be released into the environment throughout the entire life cycle of plastic products. Herein, the leaching behavior of DBP from PVC microplastics (MPs) in freshwater and seawater and its potential risks were investigated. The results show that the plasticizer content, UV irradiation, and hydrochemical conditions have a great influence on the leaching of DBP from the MPs. The release of DBP into the environment increases proportionally with higher concentrations of additive DBP in MPs, particularly when it exceeds 15 %. The surface of MPs undergoes accelerated oxidation and increased hydrophilicity under UV radiation, thereby facilitating the leaching of DBP. Through 30 continuous leaching experiments, the leaching of DBP from MPs in freshwater and seawater can reach up to 12.28 and 5.42 mg g-1, respectively, indicating that MPs are a continuous source of DBP pollution in the aquatic environment. Moreover, phthalate pollution index (PPI) indicates that MPs can significantly increase DBP pollution in marine environment through land and sea transport processes. Therefore, we advocate that the management of MPs waste containing DBP be prioritized in coastal sustainable development.

12.
Nat Commun ; 15(1): 3870, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38719875

ABSTRACT

Micro-thermoelectric coolers are emerging as a promising solution for high-density cooling applications in confined spaces. Unlike thin-film micro-thermoelectric coolers with high cooling flux at the expense of cooling temperature difference due to very short thermoelectric legs, thick-film micro-thermoelectric coolers can achieve better comprehensive cooling performance. However, they still face significant challenges in both material preparation and device integration. Herein, we propose a design strategy which combines Bi2Te3-based thick film prepared by powder direct molding with micro-thermoelectric cooler integrated via phase-change batch transfer. Accurate thickness control and relatively high thermoelectric performance can be achieved for the thick film, and the high-density-integrated thick-film micro-thermoelectric cooler exhibits excellent performance with maximum cooling temperature difference of 40.6 K and maximum cooling flux of 56.5 W·cm-2 at room temperature. The micro-thermoelectric cooler also shows high temperature control accuracy (0.01 K) and reliability (over 30000 cooling cycles). Moreover, the device demonstrates remarkable capacity in power generation with normalized power density up to 214.0 µW · cm-2 · K-2. This study provides a general and scalable route for developing high-performance thick-film micro-thermoelectric cooler, benefiting widespread applications in thermal management of microsystems.

13.
Proc Natl Acad Sci U S A ; 121(21): e2319519121, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38753508

ABSTRACT

Transforming smallholder farms is critical to global food security and environmental sustainability. The science and technology backyard (STB) platform has proved to be a viable approach in China. However, STB has traditionally focused on empowering smallholder farmers by transferring knowledge, and wide-scale adoption of more sustainable practices and technologies remains a challenge. Here, we report on a long-term project focused on technology scale-up for smallholder farmers by expanding and upgrading the original STB platform (STB 2.0). We created a formalized and standardized process by which to engage and collaborate with farmers, including integrating their feedback via equal dialogues in the process of designing and promoting technologies. Based on 288 site-year of field trials in three regions in the North China Plain over 5 y, we find that technologies cocreated through this process were more easily accepted by farmers and increased their crop yields and nitrogen factor productivity by 7.2% and 28.1% in wheat production and by 11.4% and 27.0% in maize production, respectively. In promoting these technologies more broadly, we created a "one-stop" multistakeholder program involving local government agencies, enterprises, universities, and farmers. The program was shown to be much more effective than the traditional extension methods applied at the STB, yielding substantial environmental and economic benefits. Our study contributes an important case study for technology scale-up for smallholder agriculture. The STB 2.0 platform being explored emphasizes equal dialogue with farmers, multistakeholder collaboration, and long-term investment. These lessons may provide value for the global smallholder research and practitioners.


Subject(s)
Agriculture , China , Agriculture/methods , Farmers , Humans , Crops, Agricultural/growth & development , Cooperative Behavior , Zea mays/growth & development , Sustainable Development , Conservation of Natural Resources/methods , Triticum/growth & development , Crop Production/methods
14.
BMC Cancer ; 24(1): 570, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38714987

ABSTRACT

BACKGROUND: Gastric cancer (GC) is one of the most prevalent malignant tumors worldwide and is associated with high morbidity and mortality rates. However, the specific biomarkers used to predict the postoperative prognosis of patients with gastric cancer remain unknown. Recent research has shown that the tumor microenvironment (TME) has an increasingly positive effect on anti-tumor activity. This study aims to build signatures to study the effect of certain genes on gastric cancer. METHODS: Expression profiles of 37 T cell-related genes and their TME characteristics were comprehensively analyzed. A risk signature was constructed and validated based on the screened T cell-related genes, and the roles of hub genes in GC were experimentally validated. RESULTS: A novel T cell-related gene signature was constructed based on CD5, ABCA8, SERPINE2, ESM1, SERPINA5, and NMU. The high-risk group indicated lower overall survival (OS), poorer immune efficacy, and higher drug resistance, with SERPINE2 promoting GC cell proliferation, according to experiments. SERPINE2 and CXCL12 were significantly correlated, indicating poor OS via the Youjiang cohort. CONCLUSIONS: This study identified T cell-related genes in patients with stomach adenocarcinoma (STAD) for prognosis estimation and proposed potential immunotherapeutic targets for STAD.


Subject(s)
Adenocarcinoma , Biomarkers, Tumor , Stomach Neoplasms , Tumor Microenvironment , Stomach Neoplasms/genetics , Stomach Neoplasms/immunology , Stomach Neoplasms/pathology , Stomach Neoplasms/mortality , Humans , Tumor Microenvironment/immunology , Tumor Microenvironment/genetics , Adenocarcinoma/genetics , Adenocarcinoma/immunology , Adenocarcinoma/pathology , Prognosis , Biomarkers, Tumor/genetics , Gene Expression Regulation, Neoplastic , T-Lymphocytes, Regulatory/immunology , Gene Expression Profiling , Male , Female
15.
PLoS One ; 19(5): e0303148, 2024.
Article in English | MEDLINE | ID: mdl-38753690

ABSTRACT

BACKGROUND: As a geriatric syndrome, sarcopenia has a high prevalence in the old population and represents an impaired state of health with adverse health outcomes. A strong clinical interest in its relationship with venous thromboembolism (VTE), which is a complex trait disease with a heterogeneous annual incidence rate in different countries, has emerged. The relationship between sarcopenia and venous thromboembolism has been reported in observational studies but the causality from sarcopenia to VTE remained unclarified. We aimed to assess the causal effect of sarcopenia on the risk of VTE with the two-sample Mendelian randomization (MR) method. METHODS: Two sets of single-nucleotide polymorphisms (SNPs), derived from two published genome-wide association study (GWAS) meta-analyses and genetically indexing muscle weakness and lean muscle mass separately, were pooled into inverse variance weighted (IVW), weighted median and MR-Egger analyses. RESULTS: No evidence was found for the causal effect of genetically predicted muscle weakness (IVW: OR = 0.90, 95% CI = 0.76-1.06, p = 0.217), whole body lean mass (IVW: OR = 1.01, 95% CI = 0.87-1.17, p = 0.881) and appendicular lean mass (IVW: OR = 1.13, 95% CI = 0.82-1.57, p = 0.445) on the risk of VTE. However, both genetically predicted whole-body lean mass and appendicular lean mass can causally influence diabetes mellitus (IVW of whole-body lean mass: OR = 0.87, 95% CI = 0.78-0.96, p = 0.008; IVW of appendicular lean mass: OR = 0.71, 95% CI = 0.54-0.94, p = 0.014) and hypertension (IVW of whole-body lean mass: OR = 0.92, 95% CI = 0.87-0.98, p = 0.007; IVW of appendicular lean mass: OR = 0.84, 95% CI = 0.73-0.96, p = 0.013). CONCLUSIONS: Genetically predicted sarcopenia does not causally influence VTE directly, but it might still have an indirect effect on VTE incidence via diabetes mellitus and hypertension.


Subject(s)
Genome-Wide Association Study , Mendelian Randomization Analysis , Polymorphism, Single Nucleotide , Sarcopenia , Venous Thromboembolism , Humans , Sarcopenia/genetics , Sarcopenia/epidemiology , Sarcopenia/complications , Venous Thromboembolism/genetics , Venous Thromboembolism/etiology , Venous Thromboembolism/epidemiology , Risk Factors
16.
J Craniofac Surg ; 2024 May 17.
Article in English | MEDLINE | ID: mdl-38758539

ABSTRACT

Hemimasticatory spasm (HMS) combined with hemifacial atrophy is a rare clinical entity with an unclear etiology. The authors report a 58-year-old female suffering from HMS and hemifacial atrophy, which performed microvascular decompression plus partial resection of the trigeminal nerve motor root, which is the first report in worldwide. The vascular compression of the trigeminal nerve motor root was found in surgery, the authors completed the aforementioned surgical method. The symptoms of HMS disappeared after surgery but recurred after 8 months.

17.
J Colloid Interface Sci ; 671: 344-353, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38815371

ABSTRACT

In view of a catalyst layer (CL) with low-Pt causing higher local transport resistance of O2 (Rlocal), we propose a multi-study methodology that combines CO poisoning, the limiting current density method, and electrochemical impedance spectroscopy to reveal how real CL interfaces dominate Rlocal. Experimental results indicate that the ionomer is not evenly distributed on the catalyst surface, and the uniformity of ionomer distribution does not show a positive correlation with the ionomer content. When the ionomer coverage on the supported catalyst surface is below 20 %, the ECSA is only 10 m2·g-1, and the ionomer coverage on the supported catalyst surface reaches 60 %, the ECSA is close to 40 m2·g-1. The ECSA has a positive correlation with ionomer coverage. Because the ECSA is measured by CO poisoning, it can be inferred that the platinum contacted with ionomer can generate effective active sites. Furthermore, a more uniform distribution of ionomer can create additional proton transport channels and reduce the distance for oxygen transport from the catalyst layer bulk to the active sites. A higher ECSA and a shorter distance for oxygen transport will reduce the Rlocal, leading to better performance.

18.
Anal Chem ; 96(16): 6158-6169, 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38602477

ABSTRACT

Raman spectroscopy has been widely used for label-free biomolecular analysis of cells and tissues for pathological diagnosis in vitro and in vivo. AI technology facilitates disease diagnosis based on Raman spectroscopy, including machine learning (PCA and SVM), manifold learning (UMAP), and deep learning (ResNet and AlexNet). However, it is not clear how to optimize the appropriate AI classification model for different types of Raman spectral data. Here, we selected five representative Raman spectral data sets, including endometrial carcinoma, hepatoma extracellular vesicles, bacteria, melanoma cell, diabetic skin, with different characteristics regarding sample size, spectral data size, Raman shift range, tissue sites, Kullback-Leibler (KL) divergence, and significant Raman shifts (i.e., wavenumbers with significant differences between groups), to explore the performance of different AI models (e.g., PCA-SVM, SVM, UMAP-SVM, ResNet or AlexNet). For data set of large spectral data size, Resnet performed better than PCA-SVM and UMAP. By building data characteristic-assisted AI classification model, we optimized the network parameters (e.g., principal components, activation function, and loss function) of AI model based on data size and KL divergence etc. The accuracy improved from 85.1 to 94.6% for endometrial carcinoma grading, from 77.1 to 90.7% for hepatoma extracellular vesicles detection, from 89.3 to 99.7% for melanoma cell detection, from 88.1 to 97.9% for bacterial identification, from 53.7 to 85.5% for diabetic skin screening, and mean time expense of 5 s.


Subject(s)
Spectrum Analysis, Raman , Spectrum Analysis, Raman/methods , Humans , Female , Endometrial Neoplasms/pathology , Endometrial Neoplasms/diagnosis , Endometrial Neoplasms/chemistry , Machine Learning , Melanoma/pathology , Melanoma/diagnosis , Melanoma/classification , Extracellular Vesicles/chemistry , Support Vector Machine , Bacteria/classification , Bacteria/isolation & purification , Artificial Intelligence
19.
Angew Chem Int Ed Engl ; 63(25): e202403949, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38613188

ABSTRACT

Quasi-solid polymer electrolyte (QPE) lithium (Li)-metal battery holds significant promise in the application of high-energy-density batteries, yet it suffers from low ionic conductivity and poor oxidation stability. Herein, a novel self-built electric field (SBEF) strategy is proposed to enhance Li+ transportation and accelerate the degradation dynamics of carbon-fluorine bond cleavage in LiTFSI by optimizing the termination of MXene. Among them, the SBEF induced by dielectric Nb4C3F2 MXene effectively constructs highly conductive LiF-enriched SEI and CEI stable interfaces, moreover, enhances the electrochemical performance of the QPE. The related Li-ion transfer mechanism and dual-reinforced stable interface are thoroughly investigated using ab initio molecular dynamics, COMSOL, XPS depth profiling, and ToF-SIMS. This comprehensive approach results in a high conductivity of 1.34 mS cm-1, leading to a small polarization of approximately 25 mV for Li//Li symmetric cell after 6000 h. Furthermore, it enables a prolonged cycle life at a high voltage of up to 4.6 V. Overall, this work not only broadens the application of MXene for QPE but also inspires the great potential of the self-built electric field in QPE-based high-voltage batteries.

20.
Research (Wash D C) ; 7: 0350, 2024.
Article in English | MEDLINE | ID: mdl-38585329

ABSTRACT

Intervertebral disc degeneration (IVDD) is a prevalent cause of low back pain and a leading contributor to disability. IVDD progression involves pathological shifts marked by low-grade inflammation, extracellular matrix remodeling, and metabolic disruptions characterized by heightened glycolytic pathways, mitochondrial dysfunction, and cellular senescence. Extensive posttranslational modifications of proteins within nucleus pulposus cells and chondrocytes play crucial roles in reshaping the intervertebral disc phenotype and orchestrating metabolism and inflammation in diverse contexts. This review focuses on the pivotal roles of phosphorylation, ubiquitination, acetylation, glycosylation, methylation, and lactylation in IVDD pathogenesis. It integrates the latest insights into various posttranslational modification-mediated metabolic and inflammatory signaling networks, laying the groundwork for targeted proteomics and metabolomics for IVDD treatment. The discussion also highlights unexplored territories, emphasizing the need for future research, particularly in understanding the role of lactylation in intervertebral disc health, an area currently shrouded in mystery.

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