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1.
Int J Biol Macromol ; : 134363, 2024 Jul 30.
Article in English | MEDLINE | ID: mdl-39089556

ABSTRACT

Acetyl-coenzyme A carboxylase (ACC) and diacylglycerol acyltransferase 2 (DGAT2) are recognized as potential therapeutic targets for nonalcoholic fatty liver disease (NAFLD). Inhibitors targeting ACC and DGAT2 have exhibited the capacity to reduce hepatic fat in individuals afflicted with NAFLD. However, there are no reports of dual inhibitors targeting ACC and DGAT2 for the treatment of NAFLD. Here, we aimed to identify potential dual inhibitors of ACC and DGAT2 using an integrated in silico approach. Machine learning-based virtual screening of commercial molecule databases yielded 395,729 hits, which were subsequently subjected to molecular docking aimed at both the ACC and DGAT2 binding sites. Based on the docking scores, nine compounds exhibited robust interactions with critical residues of both ACC and DGAT2, displaying favorable drug-like features. MDs unveiled the substantial impact of these compounds on the conformational dynamics of the proteins. Furthermore, binding free energy assessments highlighted the notable binding affinities of specific compounds (V003-8107, G340-0503, Y200-1700, E999-1199, V003-6429, V025-4981, V006-1474, V025-0499, and V021-8916) to ACC and DGAT2. The compounds proposed in this study, identified using a multifaceted computational strategy, warrant experimental validation as potential dual inhibitors of ACC and DGAT2, with implications for the future development of novel drugs targeting NAFLD.

2.
Nat Mater ; 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-39134650

ABSTRACT

Hexagonal boron nitride (hBN) has emerged as a promising protection layer for dielectric integration in the next-generation large-scale integrated electronics. Although numerous efforts have been devoted to growing single-crystal hBN film, wafer-scale ultraflat hBN has still not been achieved. Here, we report the epitaxial growth of 4 in. ultraflat single-crystal hBN on Cu0.8Ni0.2(111)/sapphire wafers. The strong coupling between hBN and Cu0.8Ni0.2(111) suppresses the formation of wrinkles and ensures the seamless stitching of parallelly aligned hBN domains, resulting in an ultraflat single-crystal hBN film on a wafer scale. Using the ultraflat hBN as a protective layer, we integrate the wafer-scale ultrathin high-κ dielectrics onto two-dimensional (2D) materials with a damage-free interface. The obtained hBN/HfO2 composite dielectric exhibits an ultralow current leakage (2.36 × 10-6 A cm-2) and an ultrathin equivalent oxide thickness of 0.52 nm, which meets the targets of the International Roadmap for Devices and Systems. Our findings pave the way to the synthesis of ultraflat 2D materials and integration of future 2D electronics.

3.
Addict Behav ; 158: 108127, 2024 Aug 06.
Article in English | MEDLINE | ID: mdl-39127026

ABSTRACT

OBJECTIVE: This systematic review aims to assess the feasibility, acceptability, and efficacy of exercise-based interventions in reducing craving levels among individuals with drug dependency. METHODS: This study included randomized controlled trials that investigated the effects of exercise on craving levels in individuals with drug dependence. We searched for relevant literature in PubMed, Web of Science, EMbase, The Cochrane Library, CNKI, China Biomedicine, Wanfang, and VIP databases from their inception until July 2024. Two researchers independently reviewed the literature. The quality of the studies was assessed using the PEDro scale, and the GRADE profiler software was utilized to evaluate the strength of the evidence. A qualitative synthesis was performed to describe the findings. RESULTS: We included 26 studies involving a total of 1381 participants, with 787 in the experimental group and 594 in the control group. These studies were mainly conducted in China, the United States, and the United Kingdom, and were published mostly after 2018. The participants had typically been dependent on drugs for more than 5 years. The review found that exercise interventions were feasible and well-accepted, and effectively reduced drug cravings. Among the 26 studies, 22 showed positive outcomes in reducing cravings. The type of exercise appears to be a crucial factor. Aerobic exercises were more effective than resistance exercises. Out of 18 studies that included aerobic exercises, 17 reported significant reductions in cravings. In contrast, among the 4 studies that included resistance exercises, 3 did not find a significant impact on cravings. CONCLUSION: Exercise is highly feasible and acceptable, significantly contributing to the reduction of drug cravings among individuals with drug dependency. The specific type of exercise appears to be a key determinant of the intervention's effectiveness. Aerobic exercises were more effective than resistance exercises. The evidence supporting these findings is of high quality, with an average score of 6.92 on the PEDro scale. OTHERS: The research was supported by the Shanghai Key Laboratory of Human Performance, with the project number 11DZ2261100. Registration details can be found on PROSPEO under the number CRD42024525700 at www.crd.york.ac.uk.

4.
Nat Commun ; 15(1): 6542, 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39095352

ABSTRACT

Phosphorus pentamers (cyclo-P5) are unstable in nature but can be synthesized at the Ag(111) surface. Unlike monolayer black phosphorous, little is known about their electronic properties when in contact with metal electrodes, although this is crucial for future applications. Here, we characterize the atomic structure of cyclo-P5 assembled on Ag(111) using atomic force microscopy with functionalized tips and density functional theory. Combining force and tunneling spectroscopy, we find that a strong charge transfer induces an inward dipole moment at the cyclo-P5/Ag interface as well as the formation of an interface state. We probe the image potential states by field-effect resonant tunneling and quantify the increase of the local change of work function of 0.46 eV at the cyclo-P5 assembly. Our experimental approach suggest that the cyclo-P5/Ag interface has the characteristic ingredients of a p-type semiconductor-metal Schottky junction with potential applications in field-effect transistors, diodes, or solar cells.

5.
Macromol Rapid Commun ; : e2400458, 2024 Jul 29.
Article in English | MEDLINE | ID: mdl-39072838

ABSTRACT

The molecular structure of the polymer PM6 is elaborately modified through random copolymerization by incorporating simple units of either difluoro-substituted thiophene (2FT) or dicyano-substituted thiophene (2CNT). The incorporation of the 2FT unit significantly enhanced the coplanarity of the random copolymers, leading to improved molecular crystallinity, whereas the introduction of the 2CNT unit featured the opposite effect. Thanks to the optimized morphology resembling a fiber-like interpenetrating network structure, the organic solar cells based on PM6-10%2FT:IT4F showed higher and more balanced charge mobilities, achieving a power conversion efficiency (PCE) of 12.65%, which is comparable to that of PM6-based devices. For comparison, the 2CN-series random copolymers-based devices exhibited lower PCEs of ˂12%. Interestingly, a superior PCE close to 19.0% is achieved in PM6:L8-BO:PM6-20%2CN based ternary device due to the significant improvement in open-circuit voltage. This work demonstrates that the crystallinity of donor polymers can be enhanced by introducing simple structural units to strengthen the coplanarity of the backbone, thereby achieving an optimized morphology that promotes favorable charge transport.

7.
Drug Des Devel Ther ; 18: 3157-3173, 2024.
Article in English | MEDLINE | ID: mdl-39071813

ABSTRACT

Background: Tumor-Node-Metastasis (TNM) stage of gastric cancer (GC) is one of the main factors affecting clinical outcome. The aim of this study was to explore the targets related to TNM stage of GC, and screening natural bioactive drug. Methods: RNA sequencing data of the TCGA-STAD cohort were downloaded from UCSC database. Genes associated with TNM staging were identified by weighted gene co-expression network analysis (WGCNA). Univariate Cox regression, least absolute shrinkage and selection operator (LASSO), extreme gradient boosting (Xgboost), random forest (RF) and cytohubba plug-in of cytoscope were applied to screen hub genes. Natural bioactive ingredients were available from the HERB database. Molecular docking was used to evaluate the binding activity of active ingredients to the hub protein. CCK-8, flow cytometry, transwell and Western blot assays were used to analyze the effects of diosgenin on GC cells. Results: 898 TNM-related genes were screened out through WGCNA. Three genes associated with GC progression/prognosis were identified, including nuclear receptor subfamily 3 group C member 2 (NR3C2), solute carrier family 1 member 5 (SLC1A5) and FAT atypical cadherin 1 (FAT1) based on the machine learning algorithms and hub co-expression network analysis. Diosgenin had good binding activity with SLC1A5. SLC1A5 was highly expressed in GC and was closely associated with tumor stage, overall survival and immune infiltration of GC patients. Diosgenin could inhibit cell viability and invasive ability, promote apoptosis and induce cell cycle arrest in G0/G1 phase. In addition, diosgenin promoted cleaved caspase 3 expression and inhibited Ki67, cyclin D1, p-S6K1, and SLC1A5 expression levels, while the mTORC1 activator (MHY1485) reversed this phenomenon. Conclusion: For the first time, this work reports diosgenin may inhibit the activation of mTORC1 signaling through targeting SLC1A5, thereby inhibiting the malignant behaviors of GC cells.


Subject(s)
Cell Proliferation , Diosgenin , Mechanistic Target of Rapamycin Complex 1 , Molecular Docking Simulation , Stomach Neoplasms , Stomach Neoplasms/drug therapy , Stomach Neoplasms/pathology , Stomach Neoplasms/metabolism , Humans , Cell Proliferation/drug effects , Mechanistic Target of Rapamycin Complex 1/metabolism , Mechanistic Target of Rapamycin Complex 1/antagonists & inhibitors , Diosgenin/pharmacology , Diosgenin/chemistry , Apoptosis/drug effects , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Disease Progression , Drug Screening Assays, Antitumor , Minor Histocompatibility Antigens/metabolism , Minor Histocompatibility Antigens/genetics , Dose-Response Relationship, Drug , Tumor Cells, Cultured
8.
Sensors (Basel) ; 24(14)2024 Jul 11.
Article in English | MEDLINE | ID: mdl-39065881

ABSTRACT

Addressing the limitations of current railway track foreign object detection techniques, which suffer from inadequate real-time performance and diminished accuracy in detecting small objects, this paper introduces an innovative vision-based perception methodology harnessing the power of deep learning. Central to this approach is the construction of a railway boundary model utilizing a sophisticated track detection method, along with an enhanced UNet semantic segmentation network to achieve autonomous segmentation of diverse track categories. By employing equal interval division and row-by-row traversal, critical track feature points are precisely extracted, and the track linear equation is derived through the least squares method, thus establishing an accurate railway boundary model. We optimized the YOLOv5s detection model in four aspects: incorporating the SE attention mechanism into the Neck network layer to enhance the model's feature extraction capabilities, adding a prediction layer to improve the detection performance for small objects, proposing a linear size scaling method to obtain suitable anchor boxes, and utilizing Inner-IoU to refine the boundary regression loss function, thereby increasing the positioning accuracy of the bounding boxes. We conducted a detection accuracy validation for railway track foreign object intrusion using a self-constructed image dataset. The results indicate that the proposed semantic segmentation model achieved an MIoU of 91.8%, representing a 3.9% improvement over the previous model, effectively segmenting railway tracks. Additionally, the optimized detection model could effectively detect foreign object intrusions on the tracks, reducing missed and false alarms and achieving a 7.4% increase in the mean average precision (IoU = 0.5) compared to the original YOLOv5s model. The model exhibits strong generalization capabilities in scenarios involving small objects. This proposed approach represents an effective exploration of deep learning techniques for railway track foreign object intrusion detection, suitable for use in complex environments to ensure the operational safety of rail lines.

9.
J Transl Med ; 22(1): 604, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38951906

ABSTRACT

BACKGROUND: Triple-negative breast cancer (TNBC) is a recurrent, heterogeneous, and invasive form of breast cancer. The treatment of TNBC patients with paclitaxel and fluorouracil in a sequential manner has shown promising outcomes. However, it is challenging to deliver these chemotherapeutic agents sequentially to TNBC tumors. We aim to explore a precision therapy strategy for TNBC through the sequential delivery of paclitaxel and fluorouracil. METHODS: We developed a dual chemo-loaded aptamer with redox-sensitive caged paclitaxel for rapid release and non-cleavable caged fluorouracil for slow release. The binding affinity to the target protein was validated using Enzyme-linked oligonucleotide assays and Surface plasmon resonance assays. The targeting and internalization abilities into tumors were confirmed using Flow cytometry assays and Confocal microscopy assays. The inhibitory effects on TNBC progression were evaluated by pharmacological studies in vitro and in vivo. RESULTS: Various redox-responsive aptamer-paclitaxel conjugates were synthesized. Among them, AS1411-paclitaxel conjugate with a thioether linker (ASP) exhibited high anti-proliferation ability against TNBC cells, and its targeting ability was further improved through fluorouracil modification. The fluorouracil modified AS1411-paclitaxel conjugate with a thioether linker (FASP) exhibited effective targeting of TNBC cells and significantly improved the inhibitory effects on TNBC progression in vitro and in vivo. CONCLUSIONS: This study successfully developed fluorouracil-modified AS1411-paclitaxel conjugates with a thioether linker for targeted combination chemotherapy in TNBC. These conjugates demonstrated efficient recognition of TNBC cells, enabling targeted delivery and controlled release of paclitaxel and fluorouracil. This approach resulted in synergistic antitumor effects and reduced toxicity in vivo. However, challenges related to stability, immunogenicity, and scalability need to be further investigated for future translational applications.


Subject(s)
Aptamers, Nucleotide , Delayed-Action Preparations , Drug Liberation , Fluorouracil , Nucleolin , Paclitaxel , Phosphoproteins , RNA-Binding Proteins , Triple Negative Breast Neoplasms , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/pathology , Aptamers, Nucleotide/pharmacology , Aptamers, Nucleotide/chemistry , Humans , Paclitaxel/therapeutic use , Paclitaxel/pharmacology , Cell Line, Tumor , Animals , Female , Fluorouracil/pharmacology , Fluorouracil/therapeutic use , RNA-Binding Proteins/metabolism , Phosphoproteins/metabolism , Oligodeoxyribonucleotides/pharmacology , Oligodeoxyribonucleotides/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Mice, Nude , Xenograft Model Antitumor Assays , Cell Proliferation/drug effects , Oxidation-Reduction/drug effects , Mice, Inbred BALB C
10.
Sensors (Basel) ; 24(13)2024 Jul 08.
Article in English | MEDLINE | ID: mdl-39001189

ABSTRACT

The identification of safflower filament targets and the precise localization of picking points are fundamental prerequisites for achieving automated filament retrieval. In light of challenges such as severe occlusion of targets, low recognition accuracy, and the considerable size of models in unstructured environments, this paper introduces a novel lightweight YOLO-SaFi model. The architectural design of this model features a Backbone layer incorporating the StarNet network; a Neck layer introducing a novel ELC convolution module to refine the C2f module; and a Head layer implementing a new lightweight shared convolution detection head, Detect_EL. Furthermore, the loss function is enhanced by upgrading CIoU to PIoUv2. These enhancements significantly augment the model's capability to perceive spatial information and facilitate multi-feature fusion, consequently enhancing detection performance and rendering the model more lightweight. Performance evaluations conducted via comparative experiments with the baseline model reveal that YOLO-SaFi achieved a reduction of parameters, computational load, and weight files by 50.0%, 40.7%, and 48.2%, respectively, compared to the YOLOv8 baseline model. Moreover, YOLO-SaFi demonstrated improvements in recall, mean average precision, and detection speed by 1.9%, 0.3%, and 88.4 frames per second, respectively. Finally, the deployment of the YOLO-SaFi model on the Jetson Orin Nano device corroborates the superior performance of the enhanced model, thereby establishing a robust visual detection framework for the advancement of intelligent safflower filament retrieval robots in unstructured environments.

11.
Nat Commun ; 15(1): 5848, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38992071

ABSTRACT

Atomic sawtooth surfaces have emerged as a versatile platform for growth of single-crystal van der Waals layered materials. However, the mechanism governing the formation of single-crystal atomic sawtooth metal (copper or gold) films on hard substrates (tungsten or molybdenum) remains a puzzle. In this study, we aim to elucidate the formation mechanism of atomic sawtooth metal films during melting-solidification process. Utilizing molecular dynamics, we unveil that the solidification of the liquid copper initiates at a high-index tungsten facet with higher interfacial energy. Subsequent tungsten facets follow energetically favourable pathways of forming single-crystal atomic sawtooth copper film during the solidification process near melting temperature. Formation of atomic sawtooth copper film is guaranteed with a film thickness exceeding the grain size of polycrystalline tungsten substrate. We further demonstrate the successful growth of centimeter-scale single-crystal monolayer hexagonal boron nitride films on atomic sawtooth copper films and explore their potential as efficient oxygen barrier.

12.
ACS Chem Neurosci ; 15(15): 2936-2953, 2024 Aug 07.
Article in English | MEDLINE | ID: mdl-39073874

ABSTRACT

Amyloid-ß (Aß) is a peptide that undergoes self-assembly into amyloid fibrils, which compose the hallmark plaques observed in Alzheimer's disease (AD). TAR DNA-binding protein 43 (TDP-43) is a protein with mislocalization and aggregation implicated in amyotrophic lateral sclerosis and other neurodegenerative diseases. Recent work suggests that TDP-43 may interact with Aß, inhibiting the formation of amyloid fibrils and worsening AD pathology, but the molecular details of their interaction remain unknown. Using all-atom discrete molecular dynamics simulations, we systematically investigated the direct molecular interaction between Aß and TDP-43. We found that Aß monomers were able to bind near the flexible nuclear localization sequence of the N-terminal domain (NTD) of TDP-43, adopting ß-sheet rich conformations that were promoted by the interaction. Furthermore, Aß associated with the nucleic acid binding interface of the tandem RNA recognition motifs of TDP-43 via electrostatic interactions. Using the computational peptide array method, we found the strongest C-terminal domain interaction with Aß to be within the amyloidogenic core region of TDP-43. With experimental evidence suggesting that the NTD is necessary for inhibiting Aß fibril growth, we also simulated the NTD with an Aß40 fibril seed. We found that the NTD was able to strongly bind the elongation surface of the fibril seed via extensive hydrogen bonding and could also diffuse along the lateral surface via electrostatic interactions. Our results suggest that TDP-43 binding to the elongation surface, thereby sterically blocking Aß monomer addition, is responsible for the experimentally observed inhibition of fibril growth. We conclude that TDP-43 may promote Aß toxicity by stabilizing the oligomeric state and kinetically delaying fibril maturation.


Subject(s)
Amyloid beta-Peptides , Amyloid , DNA-Binding Proteins , Molecular Dynamics Simulation , Amyloid beta-Peptides/metabolism , DNA-Binding Proteins/metabolism , Humans , Amyloid/metabolism , Protein Binding , Alzheimer Disease/metabolism
13.
Immun Inflamm Dis ; 12(7): e1338, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38990142

ABSTRACT

BACKGROUND: Human immunodeficiency virus (HIV) infection is an important risk factor for Coronavirus Disease 2019 (COVID-19), but data on the prevalence of COVID-19 among people living with HIV (PLWH) is limited in low-income countries. Our aim was to assess the seroprevalence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) specific antibodies and associated factors among PLWH in Sierra Leone. METHODS: We conducted a cross-sectional survey of PLWH aged 18 years or older in Sierra Leone between August 2022 and January 2023. Participants were tested for SARS-CoV-2 antibodies using a rapid SARS-CoV-2 antibody (immunoglobulin M/immunoglobulin G [IgG]) kits. Stepwise logistic regression was used to explore factors associated with SARS-CoV-2 antibody seroprevalence with a significance level of p < .05. RESULTS: In our study, 33.4% (1031/3085) participants had received a COVID-19 vaccine, and 75.7% were SARS-CoV-2 IgG positive. Higher IgG seroprevalence was observed in females (77.2% vs. 71.4%, p = .001), adults over 60 years (88.2%), those with suppressed HIV RNA (80.7% vs. 51.7%, p < .001), antiretroviral therapy (ART)-experienced individuals (77.9% vs. 44.6%, p < .001), and vaccinated participants (80.7% vs. 73.2%, p < .001). Patients 60 years or older had the highest odds of IgG seroprevalence (adjusted odds ratio [aOR] = 2.73, 95% CI = 1.68-4.65). Female sex (aOR = 1.28, 95%CI = 1.05-1.56), COVID-19 vaccination (aOR = 1.54, 95% CI = 1.27-1.86), and ART (aOR = 2.20, 95% CI = 1.56-3.11) increased the odds, whereas HIV RNA ≥ 1000 copies/mL (aOR = 0.32, 95% CI = 0.26-0.40) reduced the odds of IgG seroprevalence. CONCLUSIONS: We observed a high seroprevalence of SARS-CoV-2 antibody among PLWH in Sierra Leone. We recommend the introduction of targeted vaccination for PLWH with a high risk of severe COVID-19, especially those with an unsuppressed HIV viral load.


Subject(s)
Antibodies, Viral , COVID-19 , HIV Infections , Immunoglobulin G , SARS-CoV-2 , Humans , Male , Female , COVID-19/epidemiology , COVID-19/immunology , COVID-19/blood , Sierra Leone/epidemiology , Seroepidemiologic Studies , Adult , HIV Infections/epidemiology , HIV Infections/immunology , HIV Infections/drug therapy , HIV Infections/virology , Middle Aged , SARS-CoV-2/immunology , Cross-Sectional Studies , Antibodies, Viral/blood , Immunoglobulin G/blood , Young Adult , Risk Factors , Adolescent , Aged , COVID-19 Vaccines/immunology
14.
Cell Biosci ; 14(1): 87, 2024 Jun 29.
Article in English | MEDLINE | ID: mdl-38951864

ABSTRACT

BACKGROUND: Zinc finger SWIM-type containing 4 (ZSWIM4) is a zinc finger protein with its function largely uncharacterized. In this study, we aimed to investigate the role of ZSWIM4 in gastrointestinal stromal tumors (GISTs). RESULTS: We found that ZSWIM4 expression is inhibited by the predominantly mutated protein KIT in GISTs, while conversely, ZSWIM4 inhibits KIT expression and downstream signaling. Consistent with the observation, ZSWIM4 inhibited GIST cell survival and proliferation in vitro. RNA sequencing of GISTs from KITV558A/WT mice and KITV558A/WT/ZSWIM4-/- mice showed that loss of ZSWIM4 expression increases the expression of circadian clock pathway member BMAL1 which contributes to GIST cell survival and proliferation. In addition, we found that KIT signaling increases the distribution of ZSWIM4 in the nucleus of GIST cells, and which is important for its inhibition of KIT and BMAL1. In agreement with the results in vitro, the in vivo studies showed that ZSWIM4 deficiency increases the tumorigenesis of GISTs in KITV558A/WT mice. CONCLUSIONS: Taken together, our results revealed that the entry of ZSWIM4 to the nucleus is important for its inhibition of KIT and BMAL1, ultimately attenuating GIST tumorigenesis. The results provide a novel insight in the understanding of signal transduction in GISTs and lay strong theoretical basis for the advancement of GIST treatment.

15.
Small ; : e2404274, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38966895

ABSTRACT

In this work, a highly accurate neural network potential (NNP) is presented, named PtNNP, and the exploration of the reconstruction of the Pt(001) surface and its vicinal surfaces with it. Contrary to the most accepted understanding of the Pt(001) surface reconstruction, the study reveals that the main driving force behind Pt(001) quasi-hexagonal reconstruction is not the surface stress relaxation but the increased coordination number of the surface atoms resulting in stronger intralayer binding in the reconstructed surface layer. In agreement with experimental observations, the optimized supercell size of the reconstructed Pt(001) surface contains (5 × 20) unit cells. Surprisingly, the reconstruction of the vicinal Pt(001) surfaces leads to a smooth shell-like surface layer covering the whole surface and diminishing sharp step edges.

16.
Small ; : e2404104, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38953403

ABSTRACT

Polyimide aerogels have been extensively used in thermal protection domain because they possess a combination of intrinsic characteristics of aerogels and unique features of polyimide. However, polyimide aerogels still suffer significant thermally induced shrinkage at temperatures above 200 °C, restricting their application at high temperature. Here, a novel "double-phase-networking" strategy is proposed for fabricating a lightweight and mechanically robust polyimide hybrid aerogel by forming silica-zirconia-phase networking skeletons, which possess exceptional dimensional stability in high-temperature environments and superior thermal insulation. The rational mechanism responsible for the formation of double-phase-networking aerogel is further explained, generally attributing to chemical crosslinking reactions and supramolecular hydrogen bond interactions derived from the main chains of polyimide and silane/zirconia precursor/sol. The as-prepared aerogels exhibit excellent high-temperature (270 °C) dimensional stability (5.09% ± 0.16%), anti-thermal-shock properties, and low thermal conductivity. Moreover, the hydrophobic treatment provides aerogels high water resistance with water contact angle of 136.9°, further suggestive of low moisture content of 3.6% after exposure to 70 °C and 85% relative humidity for 64 h. The proposed solution for significantly enhancing high-temperature dimensional stability and thermal insulation provides a great supporting foundation for fabricating high-performance organic aerogels as thermal protection materials in aerospace.

17.
J Chem Inf Model ; 64(13): 5303-5316, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38921060

ABSTRACT

The coexistence of amyloid-ß (Aß) and human islet amyloid polypeptide (hIAPP) in the brain and pancreas is associated with an increased risk of Alzheimer's disease (AD) and type 2 diabetes (T2D) due to their coaggregation and cross-seeding. Despite this, the molecular mechanisms underlying their interaction remain elusive. Here, we systematically investigated the cross-talk between Aß and hIAPP using atomistic discrete molecular dynamics (DMD) simulations. Our results revealed that the amyloidogenic core regions of both Aß (Aß10-21 and Aß30-41) and hIAPP (hIAPP8-20 and hIAPP22-29), driving their self-aggregation, also exhibited a strong tendency for cross-interaction. This propensity led to the formation of ß-sheet-rich heterocomplexes, including potentially toxic ß-barrel oligomers. The formation of Aß and hIAPP heteroaggregates did not impede the recruitment of additional peptides to grow into larger aggregates. Our cross-seeding simulations demonstrated that both Aß and hIAPP fibrils could mutually act as seeds, assisting each other's monomers in converting into ß-sheets at the exposed fibril elongation ends. The amyloidogenic core regions of Aß and hIAPP, in both oligomeric and fibrillar states, exhibited the ability to recruit isolated peptides, thereby extending the ß-sheet edges, with limited sensitivity to the amino acid sequence. These findings suggest that targeting these regions by capping them with amyloid-resistant peptide drugs may hold potential as a therapeutic approach for addressing AD, T2D, and their copathologies.


Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Diabetes Mellitus, Type 2 , Islet Amyloid Polypeptide , Molecular Dynamics Simulation , Alzheimer Disease/metabolism , Diabetes Mellitus, Type 2/metabolism , Islet Amyloid Polypeptide/chemistry , Islet Amyloid Polypeptide/metabolism , Humans , Amyloid beta-Peptides/metabolism , Amyloid beta-Peptides/chemistry , Protein Aggregates
18.
Science ; 384(6700): 1100-1104, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38843317

ABSTRACT

One-dimensional transition metal dichalcogenides exhibiting an enhanced bulk photovoltaic effect have the potential to exceed the Shockley-Queisser limit efficiency in solar energy harvest within p-n junction architectures. However, the collective output of these prototype devices remains a challenge. We report on the synthesis of single-crystalline WS2 ribbon arrays with defined chirality and coherent polarity through an atomic manufacturing strategy. The chirality of WS2 ribbon was defined by substrate couplings into tunable armchair, zigzag, and chiral species, and the polarity direction was determined by the ribbon-precursor interfacial energy along a coherent direction. A single armchair ribbon showed strong bulk photovoltaic effect and the further integration of ~1000 aligned ribbons with coherent polarity enabled upscaling of the photocurrent.

19.
Int J Biol Sci ; 20(8): 3061-3075, 2024.
Article in English | MEDLINE | ID: mdl-38904010

ABSTRACT

Renal fibrosis is the common pathway in the progression of chronic kidney disease (CKD). Acyloxyacyl hydrolase (AOAH) is expressed in various phagocytes and is highly expressed in proximal tubular epithelial cells (PTECs). Research shows that AOAH plays a critical role in infections and chronic inflammatory diseases, although its role in kidney injury is unknown. Here, we found that AOAH deletion led to exacerbated kidney injury and fibrosis after folic acid (FA) administration, which was reversed by overexpression of Aoah in kidneys. ScRNA-seq revealed that Aoah-/- mice exhibited increased subpopulation of CD74+ PTECs, though the percentage of total PTECs were decreased compared to WT mice after FA treatment. Additionally, exacerbated kidney injury and fibrosis seen in Aoah-/- mice was attenuated via administration of methyl ester of (S, R)-3-(4-hydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid (ISO-1), an inhibitor of macrophage inhibition factor (MIF) and CD74 binding. Finally, AOAH expression was found positively correlated with estimated glomerular filtration rate while negatively correlated with the degree of renal fibrosis in kidneys of CKD patients. Thus, our work indicates that AOAH protects against kidney injury and fibrosis by inhibiting renal tubular epithelial cells CD74 signaling pathways. Targeting kidney AOAH represents a promising strategy to prevent renal fibrosis progression.


Subject(s)
Carboxylic Ester Hydrolases , Macrophages , Animals , Mice , Macrophages/metabolism , Carboxylic Ester Hydrolases/metabolism , Carboxylic Ester Hydrolases/genetics , Humans , Antigens, Differentiation, B-Lymphocyte/metabolism , Antigens, Differentiation, B-Lymphocyte/genetics , Renal Insufficiency, Chronic/metabolism , Mice, Inbred C57BL , Male , Histocompatibility Antigens Class II/metabolism , Folic Acid/metabolism , Kidney Tubules/metabolism , Kidney Tubules/pathology , Fibrosis/metabolism , Mice, Knockout , Epithelial Cells/metabolism
20.
Adv Sci (Weinh) ; : e2401634, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38888507

ABSTRACT

Radiation enteritis is the most common complication of pelvic radiotherapy, but there is no effective prevention or treatment drug. Apoptotic T cells and their products play an important role in regulating inflammation and maintaining physiological immune homeostasis. Here it is shown that systemically infused T cell-derived apoptotic extracellular vesicles (ApoEVs) can target mice irradiated intestines and alleviate radiation enteritis. Mechanistically, radiation elevates the synthesis of intestinal 2'3' cyclic GMP-AMP (cGAMP) and activates cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) proinflammatory pathway. After systemic infusion of ApoEVs, the ectonucleotide pyrophosphatase phosphodiesterase 1 (ENPP1) enriches on the surface of ApoEVs hydrolyze extracellular cGAMP, resulting in inhibition of the cGAS-STING pathway activated by irradiation. Furthermore, after ApoEVs are phagocytosed by phagocytes, ENPP1 on ApoEVs hydrolyzed intracellular cGAMP, which serves as an intracellular cGAMP hydrolyzation mode, thereby alleviating radiation enteritis. The findings shed light on the intracellular and extracellular hydrolysis capacity of ApoEVs and their role in inflammation regulation.

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