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1.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36575566

RESUMO

Recent developments of deep learning methods have demonstrated their feasibility in liver malignancy diagnosis using ultrasound (US) images. However, most of these methods require manual selection and annotation of US images by radiologists, which limit their practical application. On the other hand, US videos provide more comprehensive morphological information about liver masses and their relationships with surrounding structures than US images, potentially leading to a more accurate diagnosis. Here, we developed a fully automated artificial intelligence (AI) pipeline to imitate the workflow of radiologists for detecting liver masses and diagnosing liver malignancy. In this pipeline, we designed an automated mass-guided strategy that used segmentation information to direct diagnostic models to focus on liver masses, thus increasing diagnostic accuracy. The diagnostic models based on US videos utilized bi-directional convolutional long short-term memory modules with an attention-boosted module to learn and fuse spatiotemporal information from consecutive video frames. Using a large-scale dataset of 50 063 US images and video frames from 11 468 patients, we developed and tested the AI pipeline and investigated its applications. A dataset of annotated US images is available at https://doi.org/10.5281/zenodo.7272660.


Assuntos
Inteligência Artificial , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Fluxo de Trabalho
2.
Nano Lett ; 24(17): 5206-5213, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38647212

RESUMO

Single Atoms Catalysts (SACs) have emerged as a class of highly promising heterogeneous catalysts, where the traditional bottom-up synthesis approaches often encounter considerable challenges in relation to aggregation issues and poor stability. Consequently, achieving densely dispersed atomic species in a reliable and efficient manner remains a key focus in the field. Herein, we report a new facile electrochemical knock-down strategy for the formation of SACs, whereby the metal Zn clusters are transformed into single atoms. While a defect-rich substrate plays a pivotal role in capturing and stabilizing isolated Zn atoms, the feasibility of this novel strategy is demonstrated through a comprehensive investigation, combining experimental and theoretical studies. Furthermore, when studied in exploring for potential applications, the material prepared shows a remarkable improvement of 58.21% for the Li+ storage and delivers a capacity over 300 Wh kg-1 after 500 cycles upon the transformation of Zn clusters into single atoms.

3.
Gut ; 73(4): 668-681, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-37973365

RESUMO

OBJECTIVES: Chronic hepatitis B (CHB) caused by HBV infection greatly increases the risk of liver cirrhosis and hepatocellular carcinoma. Hepatitis B surface antigen (HBsAg) plays critical roles in the pathogenesis of CHB. HBsAg loss is the key indicator for cure of CHB, but is rarely achieved by current approved anti-HBV drugs. Therefore, novel anti-HBV strategies are urgently needed to achieve sustained HBsAg loss. DESIGN: We developed multiple chimeric antigen receptors (CARs) based on single-chain variable fragments (scFvs, namely MA18/7-scFv and G12-scFv), respectively, targeting HBV large and small envelope proteins. Their impacts on HBsAg secretion and HBV infection, and the underlying mechanisms, were extensively investigated using various cell culture models and HBV mouse models. RESULTS: After secretory signal peptide mediated translocation into endoplasmic reticulum (ER) and secretory pathway, MA18/7-scFv and CARs blocked HBV infection and virion secretion. G12-scFv preferentially inhibited virion secretion, while both its CAR formats and crystallisable fragment (Fc)-attached versions blocked HBsAg secretion. G12-scFv and G12-CAR arrested HBV envelope proteins mainly in ER and potently inhibited HBV budding. Furthermore, G12-scFv-Fc and G12-CAR-Fc strongly suppressed serum HBsAg up to 130-fold in HBV mouse models. The inhibitory effect lasted for at least 8 weeks when delivered by an adeno-associated virus vector. CONCLUSION: CARs possess direct antiviral activity, besides the well-known application in T-cell therapy. Fc attached G12-scFv and G12-CARs could provide a novel approach for reducing circulating HBsAg.


Assuntos
Hepatite B Crônica , Hepatite B , Neoplasias Hepáticas , Receptores de Antígenos Quiméricos , Camundongos , Animais , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B/genética , Retículo Endoplasmático/metabolismo
4.
BMC Genomics ; 25(1): 74, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38233778

RESUMO

BACKGROUND: Plant growth-regulating factors (GRFs) and GRF-interacting factors (GIFs) interact with each other and collectively have important regulatory roles in plant growth, development, and stress responses. Therefore, it is of great significance to explore the systematic evolution of GRF and GIF gene families. However, our knowledge and understanding of the role of GRF and GIF genes during plant evolution has been fragmentary. RESULTS: In this study, a large number of genomic and transcriptomic datasets of algae, mosses, ferns, gymnosperms and angiosperms were used to systematically analyze the evolution of GRF and GIF genes during the evolution of plants. The results showed that GRF gene first appeared in the charophyte Klebsormidium nitens, whereas the GIF genes originated relatively early, and these two gene families were mainly expanded by segmental duplication events after plant terrestrialization. During the process of evolution, the protein sequences and functions of GRF and GIF family genes are relatively conservative. As cooperative partner, GRF and GIF genes contain the similar types of cis-acting elements in their promoter regions, which enables them to have similar transcriptional response patterns, and both show higher levels of expression in reproductive organs and tissues and organs with strong capacity for cell division. Based on protein-protein interaction analysis and verification, we found that the GRF-GIF protein partnership began to be established in pteridophytes and is highly conserved across different terrestrial plants. CONCLUSIONS: These results provide a foundation for further exploration of the molecular evolution and biological functions of GRF and GIF genes.


Assuntos
Desenvolvimento Vegetal , Plantas , Evolução Molecular , Filogenia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética
5.
BMC Plant Biol ; 24(1): 127, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383299

RESUMO

BACKGROUND: Root system architecture (RSA) exhibits significant genetic variability and is closely associated with drought tolerance. However, the evaluation of drought-tolerant cotton cultivars based on RSA in the field conditions is still underexplored. RESULTS: So, this study conducted a comprehensive analysis of drought tolerance based on physiological and morphological traits (i.e., aboveground and RSA, and yield) within a rain-out shelter, with two water treatments: well-watered (75 ± 5% soil relative water content) and drought stress (50 ± 5% soil relative water content). The results showed that principal component analysis identified six principal components, including highlighting the importance of root traits and canopy parameters in influencing drought tolerance. Moreover, the systematic cluster analysis was used to classify 80 cultivars into 5 categories, including drought-tolerant cultivars, relatively drought-tolerant cultivars, intermediate cultivars, relatively drought-sensitive cultivars, and drought-sensitive cultivars. Further validation of the drought tolerance index showed that the yield drought tolerance index and biomass drought tolerance index of the drought-tolerant cultivars were 8.97 and 5.05 times higher than those of the drought-sensitive cultivars, respectively. CONCLUSIONS: The RSA of drought-tolerant cultivars was characterised by a significant increase in average length-all lateral roots, a significant decrease in average lateral root emergence angle and a moderate root/shoot ratio. In contrast, the drought-sensitive cultivars showed a significant decrease in average length-all lateral roots and a significant increase in both average lateral root emergence angle and root/shoot ratio. It is therefore more comprehensive and accurate to assess field crop drought tolerance by considering root performance.


Assuntos
Secas , Gossypium , Gossypium/genética , Fenótipo , Água , Solo
6.
Small ; 20(12): e2307902, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37950404

RESUMO

A rational design of sulfur host is the key to conquering the"polysulfide shuttle effects" by accelerating the polysulfide conversion. Since the process involves solid-liquid-solid multistep phase transitions, purposely-engineered heterostructure catalysts with various active regions for catalyzing conversion steps correspondingly are beneficial to promote the overall conversion process. However, the functionalities of the materials surface and interface in heterostructure catalysts remain unclear. In this work, an Mo2C/MoC catalyst with abundant Mo2C surface-interface-MoC surface tri-active-region is developed by in situ converting the MoZn-metal organic framework. The experimental and simulation studies demonstrate the interface can catch long-chain polysulfides and promote their conversion. Instead, the Mo2C and MoC tend to accommodate the short-chain polysulfide and accelerate their conversion and the Li2S dissociation. Benefitting from the high catalytic ability, the Li-S battery assembled with the Mo2C/MoC-S cathode shows more discrete redox reactions and delivers a high initial capacity of 1603.6 mAh g-1 at 1 C charging-discharging rate, which is over twofolds of the one assembled using individual hosts, and 80.4% capacity can be maintained after 1000 cycles at 3 C rate. This work has demonstrated a novel synergy between the interface and material surface, which will help the future design of high-performance Li-S batteries.

7.
Small ; : e2402528, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38845027

RESUMO

The crystal structure and phase stability of a host lattice plays an important role in efficient upconversion phenomena. In stable hosts, lanthanides doping should not generally change the crystal structure of the host itself. But when phase of a system drastically changes after lanthanide doping resulting in multiple phases, accurate identification of upconverting phase remains a challenge. Herein, an attempt to synthesize lanthanide-doped NiMoO4 by microwave hydrothermal method produced MoO3/Yb2Mo4O15/NiMoO4 micro-nano composite upconversion phosphor. A combined approach of density functional theory (DFT) calculations and single-particle-level upconversion imaging has been employed to elucidate the phase stability of different phases and upconversion properties within the composite. Through single-particle-level imaging under 980 nm excitation, an unprecedented resolution in visualizing individual emitting and non-emitting regions within the composite has been achieved, thereby allowing to accurately assign the Yb2Mo4O15 as a sole upconversion emitting phase in the composite. Result of the DFT calculation further shows that the Yb2Mo4O15 phase is the most thermodynamically preferred over other lanthanide-doped phases in the composite. This comprehensive understanding not only advances the knowledge of upconversion emission from composite materials but also holds promise for tailoring optical properties of materials for various applications, including bioimaging, sensing, and photonics, where controlled light emission is crucial.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38713298

RESUMO

PURPOSE: The unsatisfactory efficacy of PD-L1 antibodies in glioblastoma (GBM) is largely due to the temporal and spatial heterogeneity of PD-L1 expression. Molecular imaging can enhance understanding of the tumor immune microenvironment and guide immunotherapy. However, highly sensitive imaging agents capable of effectively visualizing PD-L1 heterogeneity are limited. This study introduces a novel PET tracer, offering improved imaging of PD-L1 heterogeneity in GBM xenografts, with a comparative analysis to [18F]AlF-NOTA-WL12. METHODS: [18F]AlF-NOTA-PCP2 was synthesized with high purity and its affinity for PD-L1 was characterized using surface plasmon resonance (SPR) and cell binding assays. Its specificity for PD-L1 was evaluated both in vitro using various cell lines and in vivo with GBM xenograft models in NOD/SCID mice. PET/CT imaging was conducted to evaluate the tracer's biodistribution, pharmacokinetics, and ability to quantify tumoral spatial heterogeneity of PD-L1 expression. A focused comparative analysis between [18F]AlF-NOTA-PCP2 and [18F]AlF-NOTA-WL12 was conducted, examining binding affinity, biodistribution, pharmacokinetics, and imaging effectiveness in GBM xenografts. Additionally, human radiation dosimetry estimates compared the safety profiles of both tracers. RESULTS: [18F]AlF-NOTA-PCP2 demonstrated high radiochemical purity (> 95%) and a strong affinity for PD-L1, comparable to [18F]AlF-NOTA-WL12. In vitro and in vivo studies confirmed its specificity for PD-L1, with increased uptake in PD-L1 expressing cells and tumors. Toxicological profiles indicated no significant abnormalities in serum biochemical indicators or major organ tissues. MicroPET/CT imaging showed [18F]AlF-NOTA-PCP2's effectiveness in visualizing PD-L1 expression levels and spatial heterogeneity in GBM xenografts. Comparative studies revealed [18F]AlF-NOTA-PCP2's improved pharmacokinetic properties, including higher tumor-to-blood ratios and lower nonspecific liver uptake, as well as reduced radiation exposure compared to [18F]AlF-NOTA-WL12. CONCLUSION: [18F]AlF-NOTA-PCP2 distinguishes itself as an exceptionally sensitive PET/CT tracer, adept at non-invasively and accurately quantifying PD-L1 expression and its spatial heterogeneity in tumors, especially in GBM. Its favorable pharmacokinetic properties, safety profile, and high affinity for PD-L1 highlight its potential for enhancing the precision of cancer immunotherapy and guiding individualized treatment strategies. While promising, its clinical translation, especially in brain imaging, necessitates further validation in clinical trials.

9.
Eur J Nucl Med Mol Imaging ; 51(4): 1109-1120, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38030744

RESUMO

PURPOSE: Radiation-induced lung injury (RILI) is a severe side effect of radiotherapy (RT) for thoracic malignancies and we currently lack established methods for the early detection of RILI. In this study, we synthesized a new tracer, [18F]AlF-NOTA-QHY-04, targeting C-X-C-chemokine-receptor-type-4 (CXCR4) and investigated its feasibility to detect RILI. METHODS: An RILI rat model was constructed and scanned with [18F]AlF-NOTA-QHY-04 PET/CT and [18F]FDG PET/CT periodically after RT. Dynamic, blocking, autoradiography, and histopathological studies were performed on the day of peak uptake. Fourteen patients with radiation pneumonia, developed during or after thoracic RT, were subjected to PET scan using [18F]AlF-NOTA-QHY-04. RESULTS: The yield of [18F]AlF-NOTA-QHY-04 was 28.5-43.2%, and the specific activity was 27-33 GBq/µmol. [18F]AlF-NOTA-QHY-04 was mainly excreted through the kidney. Significant increased [18F]AlF-NOTA-QHY-04 uptake in the irradiated lung compared with that in the normal lung in the RILI model was observed on day 6 post-RT and peaked on day 14 post-RT, whereas no apparent uptake of [18F]FDG was shown on days 7 and 15 post-RT. MicroCT imaging did not show pneumonia until 42 days post-RT. Significant intense [18F]AlF-NOTA-QHY-04 uptake was confirmed by autoradiography. Immunofluorescence staining demonstrated expression of CXCR4 was significantly increased in the irradiated lung tissue, which correlated with results obtained from hematoxylin-eosin and Masson's trichrome staining. In 14 patients with radiation pneumonia, maximum standardized uptake values (SUVmax) were significantly higher in the irradiated lung compared with those in the normal lung. SUVmax of patients with grade 2 RILI was significantly higher than that of patients with grade 1 RILI. CONCLUSION: This study indicated that [18F]AlF-NOTA-QHY-04 PET/CT imaging can detect RILI non-invasively and earlier than [18F]FDG PET/CT in a rat model. Clinical studies verified its feasibility, suggesting the clinical potential of [18F]AlF-NOTA-QHY-04 as a PET/CT tracer for early monitoring of RILI.


Assuntos
Lesão Pulmonar , Lesões por Radiação , Pneumonite por Radiação , Humanos , Ratos , Animais , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluordesoxiglucose F18 , Lesão Pulmonar/diagnóstico por imagem , Lesão Pulmonar/etiologia , Tomografia por Emissão de Pósitrons/métodos , Pulmão/diagnóstico por imagem , Receptores CXCR4
10.
Artigo em Inglês | MEDLINE | ID: mdl-39133307

RESUMO

PURPOSE: This prospective study aims to evaluate the value of [18F]AlF-NOTA-fibroblast activation protein inhibitor (FAPI)-04 positron emission tomography-computed tomography (PET/CT) in predicting molecular subtypes of breast cancer. METHODS: The study consecutively recruited patients suspected of having breast cancer from a single center who were prospectively enrolled from July 2023 to May 2024 and underwent [18F]AlF-NOTA-FAPI-04 PET/CT. This study compared the differences in tracer uptake among breast cancers with different adverse prognostic factors and molecular subtypes. The classification performance for each molecular subtype of breast cancer was assessed using a receiver operating characteristic (ROC) curve. RESULTS: Fifty-three participants (mean age, 51 ± 11 years; 52 females) were evaluated. Breast cancer lesions with adverse prognostic factors showed higher tracer uptake. The five different molecular subtypes exhibited varying levels of uptake. The luminal A and luminal B (HER2-negative) subtypes had relatively low uptake, while the luminal B (HER2-positive), HER2-positive, and triple-negative subtypes had relatively high uptake. ROC analysis identified the max standardized uptake value (SUVmax) as a significant classifier (AUC = 0.912, P = 0.0005) for the luminal A subtype, with 100% sensitivity and 83% specificity. For predicting the luminal B (HER2-negative) subtype, SUVmax had an AUC of 0.770 (P = 0.0015). SUVmax, with an AUC of 0.781 (P = 0.003), was used to identify the triple-negative subtype tumors, resulting in a sensitivity of 100% and specificity of 51%. Lastly, the ROC curve showed the cut-off 15.40 (AUC = 0.921, P < 0.0001) could classify luminal A & luminal B (HER2-negative), and luminal B (HER2-positive) & HER2-positive & triple-negative, yielding a sensitivity of 94% and specificity of 79%. CONCLUSION: The uptake of [18F]AlF-NOTA-FAPI-04 is significantly correlated with the molecular subtypes of breast cancer, and [18F]AlF-NOTA-FAPI-04 PET/CT is a potential tool for noninvasive identification of luminal A subtypes and guidance of FAP-targeted therapies.

11.
FASEB J ; 37(11): e23214, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37773768

RESUMO

Atg2 is a key gene in autophagy formation and plays an important role in regulating aging progress. Exercise is an important tool to resist oxidative stress in cells and delay muscle aging. However, the relationship between exercise and the muscle Atg2 gene in regulating skeletal muscle aging remains unclear. Here, overexpression or knockdown of muscle Atg2 gene was achieved by constructing the AtgUAS/MhcGal4 system in Drosophila, and these flies were also subjected to an exercise intervention for 2 weeks. The results showed that both overexpression of Atg2 and exercise significantly increased the climbing speed, climbing endurance, cardiac function, and lifespan of aging flies. They also significantly up-regulated the expression of muscle Atg2, AMPK, Sirt1, and PGC-1α genes, and they significantly reduced muscle malondialdehyde and triglyceride. These positive benefits were even more pronounced when the two were combined. However, the effects of Atg2 knockdown on skeletal muscle, heart, and lifespan were reversed compared to its overexpression. Importantly, exercise ameliorated age-related changes induced by Atg2 knockdown. Therefore, current results confirmed that both overexpression of muscle Atg2 and exercise delayed age-related deteriorations of skeletal muscle, the heart function, and lifespan, and exercise could also reverse age-related changes induced by Atg2 knockdown. The molecular mechanism is related to the overexpression of the Atg2 gene and exercise, which increase the activity of the AMPK/Sirt1/PGC-1α pathway, oxidation and antioxidant balance, and lipid metabolism in aging muscle.


Assuntos
Proteínas de Drosophila , Condicionamento Físico Animal , Animais , Masculino , Humanos , Sirtuína 1/genética , Sirtuína 1/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Drosophila/metabolismo , Músculo Esquelético/metabolismo , Condicionamento Físico Animal/fisiologia , Terapia por Exercício , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Proteínas Relacionadas à Autofagia/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo
12.
Mol Pharm ; 21(3): 1515-1525, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38291578

RESUMO

Immune checkpoint inhibitors (ICIs) are a powerful treatment modality for various types of cancer. The effectiveness of ICIs is intimately connected to the binding status of antibodies to receptors. However, validated means to accurately evaluate target specificity and predict antibody efficacy in vivo are lacking. A novel peptide-based probe called Al[18F]F-NOTA-PCP1 was developed and validated for its specificity to PD-L1 in A549, U87MG, GL261, and GL261-iPDL1 cell lines, as well as in xenograft models. Then the probe was used in PET/CT scans to determine the binding status of PD-L1 antibodies (atezolizumab, avelumab, and durvalumab) in U87MG xenograft model mice. Moreover, Al[18F]F-NOTA-PCP1 was used to evaluate the impact of different treatment times and doses. Al[18F]F-NOTA-PCP1 PET/CT can be used to evaluate the interaction between PD-L1 and antibodies to determine the effectiveness of immunotherapy. By quantifying target engagement, the probe has the potential to predict the efficacy of immunotherapy and optimize the dose and treatment schedules for PD-L1 immunotherapy. This imaging agent could be a valuable tool in guiding personalized treatment strategies and improving cancer patient outcomes.


Assuntos
Compostos Heterocíclicos com 1 Anel , Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Animais , Camundongos , Antígeno B7-H1/metabolismo , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Peptídeos
13.
Arch Virol ; 169(5): 88, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565755

RESUMO

Transcription of the covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) is subject to dual regulation by host factors and viral proteins. MicroRNAs (miRNAs) can regulate the expression of target genes at the post-transcriptional level. Systematic investigation of miRNA expression in HBV infection and the interaction between HBV and miRNAs may deepen our understanding of the transcription mechanisms of HBV cccDNA, thereby providing opportunities for intervention. miRNA sequencing and real-time quantitative PCR (qRT-PCR) were used to analyze miRNA expression after HBV infection of cultured cells. Clinical samples were analyzed for miRNAs and HBV transcription-related indicators, using qRT-PCR, enzyme-linked immunoassay (ELISA), and Western blot. miRNA mimics or inhibitors were used to study their effects on the HBV life cycle. The target genes of miR-3188 and their roles in HBV cccDNA transcription were also identified. The expression of 10 miRNAs, including miR-3188, which was significantly decreased after HBV infection, was measured in clinical samples from patients with chronic HBV infection. Overexpression of miR-3188 inhibited HBV transcription, whereas inhibition of miR-3188 expression promoted HBV transcription. Further investigation confirmed that miR-3188 inhibited HBV transcription by targeting Bcl-2. miR-3188 is a key miRNA that regulates HBV transcription by targeting the host protein Bcl-2. This observation provides insights into the regulation of cccDNA transcription and suggests new targets for anti-HBV treatment.


Assuntos
Hepatite B Crônica , Hepatite B , MicroRNAs , Humanos , DNA Circular/genética , DNA Viral/genética , DNA Viral/metabolismo , Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Transcrição Viral , Replicação Viral/genética
14.
Environ Res ; 252(Pt 2): 118904, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38614203

RESUMO

CH4 serves as an important greenhouse gas, yet limited knowledge is available in global and regional CH4 cycling, particularly in widely distributed karst terrain. In this study, we investigated an upland in Puding Karst Ecosystem Research Station, and explored CH4 concentration and/or flux in atmosphere, soil and cave using a closed static chamber method and an eddy covariance system. Meanwhile, we monitored atmospheric temperature, precipitation, temperature and wind velocity in the cave entrance. The results demonstrated that atmospheric CH4 and actual soil CH4 fluxes in the source area of eddy covariance system were -0.19 ± 8.64 nmols-1m-2 and -0.16 nmols-1m-2 respectively. The CH4 concentrations in Shawan Cave exhibited 10 âˆ¼ 100-fold lower than that of the external atmosphere. CH4 oxidation rate dominated by methane-oxidizing bacteria was 1.98 nmols-1m-2 in Shawan Cave when it combined with temperature difference between cave and external atmosphere. Therefore, CH4 sink in global karst subterranean spaces was estimated at 106.2 Tg CH4 yr-1. We supplemented an understanding of CH4 cycling paths and fluxes in karst terrain, as well as CH4 sinks in karst subterranean space. Further works require to establish a karst ecosystem observation network to conduct long-term integrated studies on CH4 fluxes regarding atmosphere, soils, plants and caves.


Assuntos
Atmosfera , Cavernas , Metano , Solo , Metano/análise , Metano/metabolismo , Atmosfera/química , Solo/química , Monitoramento Ambiental/métodos , Microbiologia do Solo , Poluentes Atmosféricos/análise
15.
Nano Lett ; 23(23): 11026-11033, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38010147

RESUMO

The demand for large electromechanical performance in lead-free polycrystalline piezoelectric thin films is driven by the need for compact, high-performance microelectromechanical systems (MEMS) based devices operating at low voltages. Here we significantly enhance the electromechanical response in a polycrystalline lead-free oxide thin film by utilizing lattice-defect-induced structural inhomogeneities. Unlike prior observations in mismatched epitaxial films with limited low-frequency enhancements, we achieve large electromechanical strain in a polycrystalline (K,Na)NbO3 film integrated on silicon. This is achieved by inducing self-assembled Nb-rich planar faults with a nonstoichiometric composition. The film exhibits an effective piezoelectric coefficient of 565 pm V-1 at 1 kHz, surpassing those of lead-based counterparts. Notably, lattice defect growth is substrate-independent, and the large electromechanical response is extended to even higher frequencies in a polycrystalline film. Improved properties arise from unique lattice defect morphology and frequency-dependent relaxation behavior, offering a new route to remarkable electromechanical response in polycrystalline thin films.

16.
Int J Mol Sci ; 25(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38203736

RESUMO

Lung cancer is one of the most common and intractable malignancies. It is associated with low survival rates despite existing treatments, indicating that new and more effective therapies are urgently needed such as the chimeric antigen receptor-T (CAR-T) cell immunotherapy. The cell-surface glucose-regulated protein 78 (csGRP78) is expressed in various hematological malignancies and solid tumor cells including lung cancer in response to cancer-related endoplasmic reticulum stress, while GRP78 is restricted to inside the normal cells. Here, we detected the prominent expression of csGRP78 in both lung cancer cell lines, A549 and H1299, as well as cancer stemlike cells derived from A549 by immunofluorescence. Next, a csGRP78-targeted CAR was constructed, and the transduced CAR-T cells were tested for their potency to kill the two lung cancer cell lines and derived stemlike cells, which was correlated with specific interferon γ release in vitro. Finally, we found that csGRP78 CAR-T cells also efficiently killed both lung cancer cells and cancer stemlike cells, resulting into the elimination of tumor xenografts in vivo, neither with any evidence of relapse after 63 days of tumor clearance nor any detrimental impact on other body organs we examined. Our study reveals the capacity of csGRP78 as a therapeutic target and offers valuable insight into the development of csGRP78 CAR-T cells as potential therapy for lung cancer.


Assuntos
Neoplasias Pulmonares , Receptores de Antígenos Quiméricos , Humanos , Neoplasias Pulmonares/terapia , Xenoenxertos , Chaperona BiP do Retículo Endoplasmático , Recidiva Local de Neoplasia , Proteínas de Membrana , Glucose , Linfócitos T
17.
Angew Chem Int Ed Engl ; 63(3): e202313791, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38050643

RESUMO

The blend nanomorphology of electron-donor (D) and -acceptor (A) materials is of vital importance to achieving highly efficient organic solar cells. Exogenous additives especially aromatic additives are always needed to further optimize the nanomorphology of blend films, which is hardly compatible with industrial manufacture. Herein, we proposed a unique approach to meticulously modulate the aggregation behavior of NFAs in both crystal and thin film nanomorphology via self-regulation effect. Nonfullerene acceptor Z9 was designed and synthesized by tethering phenyl groups on the inner side chains of the Y6 backbone. Compared with Y6, the tethered phenyl groups participated in the molecular aggregation via the π-π stacking of phenyl-phenyl and phenyl-2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (IC-2F) groups, which induced 3D charge transport with phenyl-mediated super-exchange electron coupling. Moreover, ordered molecular packing with suitable phase separation was observed in Z9-based blend films. High power conversion efficiencies (PCEs) of 19.0 % (certified PCE of 18.6 %) for Z9-based devices were achieved without additives, indicating the great potential of the self-regulation strategy in NFA design.

18.
Angew Chem Int Ed Engl ; 63(16): e202314796, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38391058

RESUMO

Zinc-air batteries (ZABs) have attracted considerable attention for their high energy density, safety, low noise, and eco-friendliness. However, the capacity of mechanically rechargeable ZABs was limited by the cumbersome procedure for replacing the zinc anode, while electrically rechargeable ZABs suffer from issues including low depth of discharge, zinc dendrite and dead zinc formation, and sluggish oxygen evolution reaction, etc. To address these issues, we report a hybrid redox-mediated zinc-air fuel cell (HRM-ZAFC) utilizing 7,8-dihydroxyphenazine-2-sulfonic acid (DHPS) as the anolyte redox mediator, which shifts the zinc oxidation reaction from the electrode surface to a separate fuel tank. This approach decouples fuel feeding and electricity generation, providing greater operation flexibility and scalability for large-scale power generation applications. The DHPS-mediated ZAFC exhibited a superior peak power density of 0.51 W/cm2 and a continuous discharge capacity of 48.82 Ah with ZnO as the discharge product in the tank, highlighting its potential for power generation.

19.
Small ; 19(41): e2303226, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37312403

RESUMO

A cross-linking strategy can result in a three-dimensional network of interconnected chains for the copolymers, thereby improving their mechanical performance. In this work, a series of cross-linked conjugated copolymers, named PC2, PC5, and PC8, constructed with different ratios of monomers are designed and synthesized. For comparison, a random linear copolymer, PR2 is also synthesized based on the similar monomers. When blended with Y6 acceptor, the cross-linked polymers PC2, PC5, and PC8-based polymer solar cells (PSCs) achieve superior power conversion efficiencies (PCEs) of 17.58%, 17.02%, and 16.12%, respectively, which are higher than that (15.84%) of the random copolymer PR2-based devices. Moreover, the PCE of PC2:Y6-based flexible PSC retains ≈88% of the initial efficiency value after 2000 bending cycles, overwhelming the PR2:Y6-based device with the remaining 12.8% of the initial PCE. These results demonstrate that the cross-linking strategy is a feasible and facile approach to developing high-performance polymer donors for the fabrication of flexible PSCs.

20.
J Transl Med ; 21(1): 493, 2023 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-37481592

RESUMO

BACKGROUND: Glioblastoma (GBM) is recognized as among the most aggressive forms of brain tumor. Patients typically present with a five-year survival rate of less than 6% with traditional surgery and chemoradiotherapy, which calls for novel immunotherapies like chimeric antigen receptor T (CAR-T) cells therapy. In response to endoplasmic reticulum (ER) stress in multiple tumor cells including GBM, the glucose-regulated protein 78 (GRP78) expression increases and the protein is partially translocated to the cell surface, while it is restricted to the cytoplasm and the nucleus in normal cells. METHODS: In this study, to target the cell surface GRP78 (csGRP78), CAR-T cells based on its binding peptide were generated. In vitro two GBM cell lines and glioma stem cells (GSCs) were used to confirm the localization of csGRP78 and the cytotoxicity of the CAR-T cells. In vivo a GBM xenograft model was used to assess the killing activity and the safety of the CAR-T cells. RESULTS: We confirmed the localization of csGRP78 at the cell surface of two GBM cell lines (U-251MG and U-87MG) and in GSCs. Co-culture experiments revealed that the CAR-T cells could specifically kill the GBM tumor cells and GSCs with specific IFN-γ release. Furthermore, in the tumor xenograft model, the CAR-T cells could decrease the number of GSCs and significantly suppress tumor cell growth. Importantly, we found no obvious off-target effects or T cell infiltration in major organs following systemic administration of these cells. CONCLUSIONS: The csGRP78 targeted CAR-T cells efficiently kill GBM tumor cells and GSCs both in vitro and in vivo, and ultimately suppress the xenograft tumors growth without obvious tissue injuries. Therefore, our study demonstrates that csGRP78 represents a valuable target and the csGRP78-targeted CAR-T cells strategy is an effective immunotherapy against GBM.


Assuntos
Glioblastoma , Glioma , Receptores de Antígenos Quiméricos , Humanos , Animais , Glioblastoma/terapia , Proteínas de Membrana , Chaperona BiP do Retículo Endoplasmático , Células-Tronco Neoplásicas , Modelos Animais de Doenças
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