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1.
Chin Med J (Engl) ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38721807

RESUMO

BACKGROUND: The ability to generate functional hepatocytes without relying on donor liver organs holds significant therapeutic promise in the fields of regenerative medicine and potential liver disease treatments. Clustered regularly interspaced short palindromic repeats (CRISPR) activator (CRISPRa) is a powerful tool that can conveniently and efficiently activate the expression of multiple endogenous genes simultaneously, providing a new strategy for cell fate determination. The main purpose of this study is to explore the feasibility of applying CRISPRa for hepatocyte reprogramming and its application in the treatment of mouse liver fibrosis. METHOD: The differentiation of mouse embryonic fibroblasts (MEFs) into functional induced hepatocyte-like cells (iHeps) was achieved by utilizing the CRISPRa synergistic activation mediator (SAM) system, which drove the combined expression of three endogenous transcription factors-Gata4, Foxa3, and Hnf1a-or alternatively, the expression of two transcription factors, Gata4 and Foxa3. In vivo, we injected adeno-associated virus serotype 6 (AAV6) carrying the CRISPRa SAM system into liver fibrotic Col1a1-CreER; Cas9fl/fl mice, effectively activating the expression of endogenous Gata4 and Foxa3 in fibroblasts. The endogenous transcriptional activation of genes was confirmed using real-time quantitative polymerase chain reaction (RT-qPCR) and RNA-seq, and the morphology and characteristics of the induced hepatocytes were observed through microscopy. The level of hepatocyte reprogramming in vivo is detected by immunofluorescence staining, while the improvement of liver fibrosis is evaluated through Sirius red staining, alpha-smooth muscle actin (α-SMA) immunofluorescence staining, and blood alanine aminotransferase (ALT) examination. RESULTS: Activation of only two factors, Gata4 and Foxa3, via CRISPRa was sufficient to successfully induce the transformation of MEFs into iHeps. These iHeps could be expanded in vitro and displayed functional characteristics similar to those of mature hepatocytes, such as drug metabolism and glycogen storage. Additionally, AAV6-based delivery of the CRISPRa SAM system effectively induced the hepatic reprogramming from fibroblasts in mice with live fibrosis. After 8 weeks of induction, the reprogrammed hepatocytes comprised 0.87% of the total hepatocyte population in the mice, significantly reducing liver fibrosis. CONCLUSION: CRISPRa-induced hepatocyte reprogramming may be a promising strategy for generating functional hepatocytes and treating liver fibrosis caused by hepatic diseases.

2.
Sensors (Basel) ; 24(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38732987

RESUMO

Full waveform inversion (FWI) is recognized as a leading data-fitting methodology, leveraging the detailed information contained in physical waveform data to construct accurate, high-resolution velocity models essential for crosshole surveys. Despite its effectiveness, FWI is often challenged by its sensitivity to data quality and inherent nonlinearity, which can lead to instability and the inadvertent incorporation of noise and extraneous data into inversion models. To address these challenges, we introduce the scale-aware edge-preserving FWI (SAEP-FWI) technique, which integrates a cutting-edge nonlinear anisotropic hybrid diffusion (NAHD) filter within the gradient computation process. This innovative filter effectively reduces noise while simultaneously enhancing critical small-scale structures and edges, significantly improving the fidelity and convergence of the FWI inversion results. The application of SAEP-FWI across a variety of experimental and authentic crosshole datasets clearly demonstrates its effectiveness in suppressing noise and preserving key scale-aware and edge-delineating features, ultimately leading to clear inversion outcomes. Comparative analyses with other FWI methods highlight the performance of our technique, showcasing its ability to produce images of notably higher quality. This improvement offers a robust solution that enhances the accuracy of subsurface imaging.

3.
Chin Clin Oncol ; 13(2): 20, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38711180

RESUMO

BACKGROUND: The ideal treatment for giant cell tumor of bone (GCTB) is still controversial. Various surgical adjuvants have been introduced following intralesional curettage to improve local control rates. However, findings from relevant studies are inconsistent, and no consensus has been reached. The purpose of this study is to determine what intraoperative adjuvant is effective in decreasing the recurrence of GCTB. METHODS: We performed a systematic review and meta-analysis of articles published in the PubMed and Embase electronic databases which assessed the recurrence rate of GCTB following intralesional curettage with or without various surgical adjuvants. Two authors independently evaluated all publications. Meta-analysis was performed with Stata/MP (Version 17.0, StataCorp LLC, TX, USA) and Review Manager (RevMan, Version 5.4.1, The Cochrane Collaboration, 2020). Pooled risk ratio (RR) was used for analysis, with P values less than 0.05 considered statistically significant. RESULTS: Twenty-four studies involving 2,579 patients were included in this analysis. The overall recurrence rates for patients treated with or without high-speed burring (HSB) are 11.9% (26/218) and 47.7% (92/193), respectively. The pooled RR for tumor recurrence is 0.33 (95% CI: 0.22 to 0.49, P<0.001). In the meanwhile, the overall recurrence rates for patients treated with or without chemical adjuvants are 23.5% (77/328) and 26.1% (73/280), respectively, with a pooled RR of 0.84 (95% CI: 0.63 to 1.10, P=0.89). Additionally, the overall recurrence rates for patients treated with or without polymethyl methacrylate (PMMA) are 20.4% (205/1,006) and 33.4% (314/939), respectively, with a pooled RR of 0.59 (95% CI: 0.50 to 0.69, P<0.001). CONCLUSIONS: Intraoperative application of HSB or PMMA has an additional antitumor effect, while the use of phenol or H2O2 fails to make any significant difference (PROSPERO: CRD42022344262).


Assuntos
Neoplasias Ósseas , Curetagem , Tumor de Células Gigantes do Osso , Humanos , Tumor de Células Gigantes do Osso/cirurgia , Curetagem/métodos , Neoplasias Ósseas/cirurgia , Neoplasias Ósseas/patologia
4.
Stem Cell Res Ther ; 15(1): 137, 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38735979

RESUMO

Scar tissue is the inevitable result of repairing human skin after it has been subjected to external destructive stimuli. It leads to localized damage to the appearance of the skin, accompanied by symptoms such as itching and pain, which reduces the quality of life of the patient and causes serious medical burdens. With the continuous development of economy and society, there is an increasing demand for beauty. People are looking forward to a safer and more effective method to eliminate pathological scarring. In recent years, adipose-derived stem cells (ADSCs) have received increasing attention from researchers. It can effectively improve pathological scarring by mediating inflammation, regulating fibroblast proliferation and activation, and vascular reconstruction. This review focuses on the pathophysiological mechanisms of hypertrophic scarring, summarizing the therapeutic effects of in vitro, in vivo, and clinical studies on the therapeutic effects of ADSCs in the field of hypertrophic scarring prevention and treatment, the latest application techniques, such as cell-free therapies utilizing ADSCs, and discussing the advantages and limitations of ADSCs. Through this review, we hope to further understand the characterization of ADSC and clarify the effectiveness of its application in hypertrophic scarring treatment, so as to provide clinical guidance.


Assuntos
Tecido Adiposo , Cicatriz Hipertrófica , Humanos , Cicatriz Hipertrófica/terapia , Cicatriz Hipertrófica/metabolismo , Cicatriz Hipertrófica/patologia , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Células-Tronco/metabolismo , Células-Tronco/citologia , Secretoma/metabolismo , Animais , Transplante de Células-Tronco/métodos
5.
Artigo em Inglês | MEDLINE | ID: mdl-38743551

RESUMO

The widespread usage of high-definition screens on edge devices stimulates a strong demand for efficient image restoration algorithms. The way of caching deep learning models in a look-up table (LUT) is recently introduced to respond to this demand. However, the size of a single LUT grows exponentially with the increase of its indexing capacity, which restricts its receptive field and thus the performance. To overcome this intrinsic limitation of the single-LUT solution, we propose a universal method to construct multiple LUTs like a neural network, termed MuLUT. Firstly, we devise novel complementary indexing patterns, as well as a general implementation for arbitrary patterns, to construct multiple LUTs in parallel. Secondly, we propose a re-indexing mechanism to enable hierarchical indexing between cascaded LUTs. Finally, we introduce channel indexing to allow cross-channel interaction, enabling LUTs to process color channels jointly. In these principled ways, the total size of MuLUT is linear to its indexing capacity, yielding a practical solution to obtain superior performance with the enlarged receptive field. We examine the advantage of MuLUT on various image restoration tasks, including super-resolution, demosaicing, denoising, and deblocking. MuLUT achieves a significant improvement over the single-LUT solution, e.g., up to 1.1dB PSNR for super-resolution and up to 2.8dB PSNR for grayscale denoising, while preserving its efficiency, which is 100× less in energy cost compared with lightweight deep neural networks. Our code and trained models are publicly available at https://github.com/ddlee-cn/MuLUT.

6.
Clin Mol Hepatol ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623614

RESUMO

Background/Aims: Non-alcoholic fatty liver disease (NAFLD) has become an increasingly important health challenge, with a substantial rise linked to changing lifestyles and global obesity. Ursolic acid, a natural pentacyclic triterpenoid, has been explored for its potential therapeutic effects. Given its multifunctional bioactive properties, this research further revealed the pharmacological mechanisms of ursolic acid on NAFLD. Methods: Drug target chips and bioinformatics analysis were combined in this study to explore the potential therapeutic effects of ursolic acid on NAFLD. Molecular docking simulations, surface plasmon resonance analyses, pull-down experiments, and co-immunoprecipitation assays were used to verify the direct interactions. Gene knockdown mice were generated, and high-fat diets were used to validate drug efficacy. Furthermore, initial CD4+ T cells were isolated and stimulated to demonstrate our findings. Results: In this study, the multifunctional extracellular matrix phosphorylated glycoprotein secreted phosphoprotein 1 (SPP1) was investigated, highlighting its capability to induce Th17 cell differentiation, amplifying inflammatory cascades, and subsequently promoting the evolution of NAFLD. In addition, this study revealed that in addition to the canonical TGF-ß/IL-6 cytokine pathway, SPP1 can directly interact with ITGB1 and CD44, orchestrating Th17 cell differentiation via their joint downstream ERK signaling pathway. Remarkably, ursolic acid intervention notably suppressed the protein activity of SPP1, suggesting a promising avenue for ameliorating the immunoinflammatory trajectory in NAFLD progression. Conclusions: Ursolic acid could improve immune inflammation in NAFLD by modulating SPP1-mediated Th17 cell differentiation via the ERK signaling pathway, which is orchestrated jointly by ITGB1 and CD44, emerging as a linchpin in this molecular cascade.

7.
Materials (Basel) ; 17(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38673205

RESUMO

The exceptional corrosion resistance and combined physical and chemical self-cleaning capabilities of superhydrophobic photocatalytic coatings have sparked significant interest among researchers. In this paper, we propose an economical and eco-friendly superhydrophobic epoxy resin coating that incorporates SiO2@CuO/HDTMS nanoparticles modified with Hexadecyltrimethoxysilane (HDTMS). The application of superhydrophobic coatings effectively reduces the contact area between the metal surface and corrosive media, leading to a decreased corrosion rate. Additionally, the incorporation of nanomaterials, exemplified by SiO2@CuO core-shell nanoparticles, improves the adhesion and durability of the coatings on aluminum alloy substrates. Experimental data from Tafel curve analysis and electrochemical impedance spectroscopy (EIS) confirm the superior corrosion resistance of the superhydrophobic modified aluminum alloy surface compared to untreated surfaces. Estimations indicate a significant reduction in corrosion rate after superhydrophobic treatment. Furthermore, an optical absorption spectra analysis of the core-shell nanoparticles demonstrates their suitability for photocatalytic applications, showcasing their potential contribution to enhancing the overall performance of the coated surfaces. This research underscores the promising approach of combining superhydrophobic properties with photocatalytic capabilities to develop advanced surface modification techniques for enhanced corrosion resistance and functional properties in diverse industrial settings.

8.
Comput Biol Med ; 175: 108437, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38669732

RESUMO

Gastric cancer (GC), characterized by its inconspicuous initial symptoms and rapid invasiveness, presents a formidable challenge. Overlooking postoperative intervention opportunities may result in the dissemination of tumors to adjacent areas and distant organs, thereby substantially diminishing prospects for patient survival. Consequently, the prompt recognition and management of GC postoperative recurrence emerge as a matter of paramount urgency to mitigate the deleterious implications of the ailment. This study proposes an enhanced feature selection model, bRSPSO-FKNN, integrating boosted particle swarm optimization (RSPSO) with fuzzy k-nearest neighbor (FKNN), for predicting GC. It incorporates the Runge-Kutta search, for improved model accuracy, and Gaussian sampling, enhancing the search performance and helping to avoid locally optimal solutions. It outperforms the sophisticated variants of particle swarm optimization when evaluated in the CEC 2014 test suite. Furthermore, the bRSPSO-FKNN feature selection model was introduced for GC recurrence prediction analysis, achieving up to 82.082 % and 86.185 % accuracy and specificity, respectively. In summation, this model attains a notable level of precision, poised to ameliorate the early warning system for GC recurrence and, in turn, advance therapeutic options for afflicted patients.


Assuntos
Recidiva Local de Neoplasia , Neoplasias Gástricas , Neoplasias Gástricas/patologia , Humanos , Algoritmos , Distribuição Normal
9.
Int J Biol Macromol ; 267(Pt 2): 131588, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38615860

RESUMO

Dietary selenium (Se) supplementation has recently received increasing attention; however, Selenium nanoparticles (SeNPs) exhibit poor stability and tend to aggregate in aqueous solution. Therefore, enhancing the stability of SeNPs and their effective delivery to plants remain challenging. In this study, sodium alginate (SA) and lysozyme (LZ) were reacted via the wet-heat Maillard reaction (MR) to obtain amphiphilic alginate-based polymers (SA-LZ). Alkyl glycosides (APG) were introduced into SA-LZ to enhance the deposition of SeNPs in leaves. Thus, a renewable and degradable polysaccharide-based material (SA-LZ/APG) loaded with Se formed an amphiphilic alginate-based-based shell with a Se core. Notably, the encapsulation of SeNPs into a polysaccharide base (SA-LZ/APG) increased the stabilization of SeNPs and resulted in orange-red, zero-valent, monoclinic and spherical SeNPs with a mean diameter of approximately 43.0 nm. In addition, SA-LZ/APG-SeNPs reduced the interfacial tension of plant leaves and increased the Se content of plants compared to the blank group. In vitro studies have reported that SA-LZ/APG-SeNPs and SA-LZ-SeNPs have significantly better clearance of DDPH and ABTS than that of APG-SeNPs. Thus, we believe that SA-LZ/APG is a promising smart delivery system that can synergistically enhance the stability of SeNPs in aqueous solutions and improve the bioavailability of Se nutrient solutions.


Assuntos
Alginatos , Glicosídeos , Nanopartículas , Selênio , Alginatos/química , Selênio/química , Nanopartículas/química , Glicosídeos/química , Folhas de Planta/química , Muramidase/química , Tensoativos/química , Estabilidade de Medicamentos
10.
Heliyon ; 10(5): e26368, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38434380

RESUMO

Pyruvate kinase deficiency is a rare hereditary erythrocyte enzyme disease caused by mutations in the pyruvate kinase liver and red blood cell gene. The clinical presentations of pyruvate kinase deficiency are significantly heterogeneous, ranging from just mild anemia to hemolytic crisis or even death. The proband in our study was a 2-year-old girl for severe skin and scleral icterus with progressive aggravation. We collected the family's data for further analysis. Whole exome genome sequencing of the pedigree revealed a novel compound heterozygous mutation, c.1097del (p.P366Lfs*12) and c.1493G > A (p.R498H), in the pyruvate kinase liver and red blood cell gene. Furthermore, molecular dynamics simulations were employed to uncover differences between the wild type and mutant pyruvate kinase liver and red blood cell proteins, focusing on structural stability, protein flexibility, secondary structure, and overall conformation. The combined bioinformatic tools were also utilised to assess the effects of the missense mutation on protein function. Thereafter, wild type and mutant plasmids were constructed and transfected into 293T cells, and Western blot assay was conducted to validate the impact of the mutations on the expression of pyruvate kinase liver and red blood cell protein. The data presented in our study enriches the genotype database and provides evidence for genetic counseling and molecular diagnosis of pyruvate kinase deficiency.

11.
Carbohydr Polym ; 334: 121892, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553196

RESUMO

High quantum yield polysaccharide-based materials are significative for the dynamic anti-counterfeiting, while that are limited by weak fluorescence. However, natural polysaccharides with weak fluorescence are not suitable for anti-counterfeiting. Herein, alginate derivatives (SA-PBA) exhibiting aggregation-induced emission with high-quantum yields were synthesized by grafting phenylboronic acid (PBA) onto a sodium alginate (SA) chain. As the concentration increases, polymer assembly can be induced to form more compact soft colloidal aggregates, which enhances the fluorescence properties of alginate derivatives by introducing B â† N coordination bonds in the hydrophobic microregions. Interestingly, the clustered aggregates of SA-PBA can be dynamically controlled by pH, realizing the reversible adjustment of fluorescence. The corresponding mechanism is revealed by the combination of coarse-grained simulations and experiments. It is found that SA-PBA uses a hydrophobic driving force and hydrogen bond interaction to self-assemble in an aqueous solution and promote fluorescence emission. Moreover, the fluorescence quantum yield of SA-PBA can reach 14.4 % and can be reversibly altered by tuning soft colloidal microstructures. Therefore, a reversible information encryption system of SA-PBA is developed for anti-counterfeiting. This work shed some light on how to design novel anti-counterfeit materials based on natural polysaccharides and optimize the dynamic fluorescence conditions.

13.
J Med Chem ; 67(6): 4804-4818, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38466231

RESUMO

Proteolysis-targeting chimera (PROTAC) is a powerful technology that can effectively trigger the degradation of target proteins. The intricate interplay among various factors leads to a heterogeneous drug response, bringing about significant challenges in comprehending drug mechanisms. Our study applied data-independent acquisition-based mass spectrometry to multidimensional proteome profiling of PROTAC (DIA-MPP) to uncover the efficacy and sensitivity of the PROTAC compound. We profiled the signal transducer and activator of transcription 3 (STAT3) PROTAC degrader in six leukemia and lymphoma cell lines under multiple conditions, demonstrating the pharmacodynamic properties and downstream biological responses. Through comparison between sensitive and insensitive cell lines, we revealed that STAT1 can be regarded as a biomarker for STAT3 PROTAC degrader, which was validated in cells, patient-derived organoids, and mouse models. These results set an example for a comprehensive description of the multidimensional PROTAC pharmacodynamic response and PROTAC drug sensitivity biomarker exploration.


Assuntos
Proteoma , Fator de Transcrição STAT3 , Animais , Camundongos , Humanos , Proteoma/metabolismo , Proteólise , Fator de Transcrição STAT3/metabolismo , Linhagem Celular , Biomarcadores/metabolismo
14.
Microorganisms ; 12(3)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38543537

RESUMO

Calf intestines are colonized by rich and complex microbial communities, playing a crucial role in animal physiology, metabolism, nutrition, and immune function. In this study, we provide insight into the composition of fecal microbial bacteria and fungi, respectively, as well as the cross-kingdom interactions. We investigated the intestinal microbiota of different breeds of calves by characterizing the bacterial and fungal communities in the rectal feces of Holstein calves and German Simmental × Holstein cross F1 generation (GXH) using 16S rRNA and ITS amplicon sequencing techniques. PICRUSt2 (version 2.2.0) were used to determine microbial diversity and function and explore the reasons why Holstein calves are more susceptible to diarrhea. The results revealed no significant difference in the diversity of fecal microbiota among the groups (p > 0.05). We identified Firmicutes, Bacteroidetes, and Proteobacteria as the dominant bacterial phyla in the fecal bacterial communities of the two breeds of calves. Ascomycota and Basidiomycota play important roles in the fungal community but differ in relative abundance. Bacteroides was the dominant genus at the group level for calf fecal microbiota in both breeds. The relative abundance of Prevotella, Escherichia-Shigella, Peptostreptococcus, and Butyricicoccus was higher in Holstein calves, and the relative abundance of Faecalibacterium, Megamonas, Butyricicoccus, and Alloprevotella was lower than GXH group. Aspergillus and Cladosporium were the dominating genera of fecal fungi in both groups of calves. LEfSe analysis revealed 33 different bacteria and 23 different fungi between the two groups, with more differential strains found in GXH. In addition, the feces fungi-bacteria interkingdom interactions varied among breeds. Thus, the composition and structure of bacterial and fungal communities in calf feces varied by breed, indicating a potential association between breed and microbial communities. We also found differences in the network between bacterial-fungal kingdoms. We explain the reasons for Holstein calves being more prone to diarrhea. This indicated that breed makes differences in calf diarrhea rates by influencing gut microbial composition and interactions.

15.
Quant Imaging Med Surg ; 14(3): 2514-2527, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38545041

RESUMO

Background: Heart failure with preserved ejection fraction (HFpEF) is a highly prevalent progressive disease accompanied by poor quality of life, high utilization of medical resources, morbidity, and mortality. However, the role of left ventricular (LV) systolic dysfunction has yet to be well elaborated despite the preservation of the LV ejection fraction. This study aimed to explore the diagnostic value of speckle-tracking stratified strain combined with myocardial work (MW) measurement in evaluating LV systolic dysfunction in patients with HFpEF. Methods: A total of 125 study consecutive individuals, 64 HFpEF patients, and 61 controls were prospectively enrolled in the Fourth Affiliated Hospital of Harbin Medical University. In addition to the conventional echocardiographic parameters, LV stratified strain and MW parameters were statistically compared between the HFpEF and control groups. The global longitudinal strain (GLS) of the subendocardium, myocardium, and subepicardium (GLSendo, GLSmyo, and GLSepi); the transmural gradient (ΔGLS); the global myocardial work index (GWI), global myocardial work efficiency (GWE), global myocardial constructive work (GCW), and the global myocardial wasted work (GWW) were included. Area under the receiver operating characteristic curve analysis was used to evaluate the diagnostic performance of these univariate and multivariable logistic models in detecting impaired LV systolic function in HFpEF. Ten-fold cross-validation was used to evaluate the generalizability of the predictive model. Results: Stratified strains values showed a gradient decline from GLSendo to GLSepi in both control and HFpEF patients. Compared with the control group, HFpEF patients had a significantly reduced GLSepi, GLSmyo, GLSendo, ΔGLS, GWI, GWE, and GCW and a significantly increased GWW (all P<0.001). In the derivation set, the optimal logistic model (combined stratified strain and MW variables) demonstrated the highest performance in predicting LV systolic function impairment in HFpEF patients. The best-performing model with a mean area under the curve (AUC) of 0.966 [95% confidence interval (CI): 0.88 to 1] accessed by 10-fold cross-validation. In the validation set, the AUC of the optimal logistic model was 0.933 (95% CI: 0.85 to 1), the sensitivity was 87%, and the specificity was 93%. Conclusions: Both speck-tracking stratified strain and MW measurement may sensitively detect impairment of LV myocardial function at an early stage for patients with HFpEF. Combining the two techniques may improve the quality of HFpEF diagnosis and may provide a reference value for the early diagnosis of HFpEF in the future.

16.
Anal Chem ; 96(10): 4023-4030, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38412242

RESUMO

Fluorescent DNA nanosensors have been widely used due to their unique advantages, among which the near-infrared (NIR) imaging mode can provide deeper penetration depth and lower biological background for the nanosensors. However, efficient NIR quenchers require ingenious design, complex synthesis, and modification, which severely limit the development of NIR DNA nanosensors. Label-free strategies based on G-quadruplex (G4) and NIR G4 dyes were first introduced into in situ extracellular imaging, and a novel NIR sensing strategy for the specific detection of extracellular targets is proposed. The strategy avoids complex synthesis and site-specific modification by controlling the change of the NIR signal through the formation of a G4 nanostructure. A light-up NIR DNA nanosensor based on potassium ion (K+)-sensitive G4 chain PS2.M was constructed to verify the strategy. PS2.M forms a stable G4 nanostructure in the presence of K+ and activates the NIR G4 dye CSTS, thus outputting NIR signals. The nanosensor can rapidly respond to K+ with a linear range of 5-50 mM and has good resistance to interference. The nanosensor with cholesterol can provide feedback on the changes in extracellular K+ concentration in many kinds of cells, serving as a potential tool for the study of diseases such as epilepsy and cancer, as well as the development of related drugs. The strategy can be potentially applied to the NIR detection of a variety of extracellular targets with the help of functional DNAs such as aptamer and DNAzyme.


Assuntos
Corantes Fluorescentes , Nanoestruturas , Corantes Fluorescentes/química , DNA/química , Potássio/química
17.
Sensors (Basel) ; 24(3)2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38339555

RESUMO

The zero-velocity update (ZUPT) algorithm is a pivotal advancement in pedestrian navigation accuracy, utilizing foot-mounted inertial sensors. Its key issue hinges on accurately identifying periods of zero-velocity during human movement. This paper introduces an innovative adaptive sliding window technique, leveraging the Fourier Transform to precisely isolate the pedestrian's gait frequency from spectral data. Building on this, the algorithm adaptively adjusts the zero-velocity detection threshold in accordance with the identified gait frequency. This adaptation significantly refines the accuracy in detecting zero-velocity intervals. Experimental evaluations reveal that this method outperforms traditional fixed-threshold approaches by enhancing precision and minimizing false positives. Experiments on single-step estimation show the adaptability of the algorithm to motion states such as slow, fast, and running. Additionally, the paper demonstrates pedestrian trajectory localization experiments under a variety of walking conditions. These tests confirm that the proposed method substantially improves the performance of the ZUPT algorithm, highlighting its potential for pedestrian navigation systems.

18.
Int J Mol Med ; 53(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38362962

RESUMO

Phospholipids (PLs) are principle constituents of biofilms, with their fatty acyl chain composition significantly impacting the biophysical properties of membranes, thereby influencing biological processes. Recent studies have elucidated that fatty acyl chains, under the enzymatic action of lyso­phosphatidyl­choline acyltransferases (LPCATs), expedite incorporation into the sn­2 site of phosphatidyl­choline (PC), profoundly affecting pathophysiology. Accumulating evidence suggests that alterations in LPCAT activity are implicated in various diseases, including non­alcoholic fatty liver disease (NAFLD), hepatitis C, atherosclerosis and cancer. Specifically, LPCAT3 is instrumental in maintaining systemic lipid homeostasis through its roles in hepatic lipogenesis, intestinal lipid absorption and lipoprotein secretion. The liver X receptor (LXR), pivotal in lipid homeostasis, modulates cholesterol, fatty acid (FA) and PL metabolism. LXR's capacity to modify PL composition in response to cellular sterol fluctuations is a vital mechanism for protecting biofilms against lipid stress. Concurrently, LXR activation enhances LPCAT3 expression on cell membranes and elevates polyunsaturated PL levels. This activation can ameliorate saturated free FA effects in vitro or endoplasmic reticulum stress in vivo due to lipid accumulation in hepatic cells. Pharmacological interventions targeting LXR, LPCAT and membrane PL components could offer novel therapeutic directions for NAFLD management. The present review primarily focused on recent advancements in understanding the LPCAT3 signaling pathway's role in lipid metabolism related to NAFLD, aiming to identify new treatment targets for the disease.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptores X do Fígado/metabolismo , Fígado/metabolismo , Metabolismo dos Lipídeos , Fosfolipídeos/metabolismo , Ácidos Graxos/metabolismo , Transdução de Sinais , Colina/metabolismo , 1-Acilglicerofosfocolina O-Aciltransferase/metabolismo , 1-Acilglicerofosfocolina O-Aciltransferase/farmacologia
19.
Oncogene ; 43(13): 944-961, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38351345

RESUMO

Metastasis causes most cancer-related deaths, and the role and mechanism of periostin (POSTN) in the metastasis of hepatocellular carcinoma (HCC) remain undiscovered. In this study, DEN and HTVi HCC models were performed in hepatic-specific Postn ablation and Postn knock-in mouse to reveal the role of POSTN in HCC metastasis. Furthermore, POSTN was positively correlated with circulating EPCs level and promoted EPC mobilization and tumour infiltration. POSTN also mediated the crosstalk between HCC and EPCs, which promoted metastasis ability and upregulated CD36 expression in HCC through indirect crosstalk. Chemokine arrays further revealed that hepatic-derived POSTN induced elevated CCL2 expression and secretion in EPCs, and CCL2 promoted prometastatic traits in HCC. Mechanistic studies showed that POSTN upregulated CCL2 expression in EPCs via the αvß3/ILK/NF-κB pathway. CCL2 further induced CD36 expression via the CCR2/STAT3 pathway by directly binding to the promoter region of CD36. Finally, CD36 was verified to have a prometastatic role in vitro and to be correlated with POSTN expression, metastasis and recurrence in HCC in clinical samples. Our findings revealed that crosstalk between HCC and EPCs is mediated by periostin/CCL2/CD36 signalling which promotes HCC metastasis and emphasizes a potential therapeutic strategy for preventing HCC metastasis.


Assuntos
Antígenos CD36 , Carcinoma Hepatocelular , Quimiocina CCL2 , Células Progenitoras Endoteliais , Neoplasias Hepáticas , Periostina , Animais , Camundongos , Carcinoma Hepatocelular/patologia , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Neoplasias Hepáticas/patologia , Transdução de Sinais/genética , Microambiente Tumoral/genética , Quimiocina CCL2/metabolismo , Antígenos CD36/metabolismo
20.
Int J Antimicrob Agents ; 63(5): 107124, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38412930

RESUMO

For successful viral propagation within infected cells, the virus needs to overcome the cellular integrated stress response (ISR), triggered during viral infection, which, in turn, inhibits general protein translation. This paper reports a tactic employed by viruses to suppress the ISR by upregulating host cell polyribonucleotide nucleotidyltransferase 1 (PNPT1). The propagation of adenovirus, murine cytomegalovirus and hepatovirus within their respective host cells induces PNPT1 expression. Notably, when PNPT1 is knocked down, the propagation of all three viruses is prevented. Mechanistically, the inhibition of PNPT1 facilitates the relocation of mitochondrial double-stranded RNAs (mt-dsRNAs) to the cytoplasm, where they activate RNA-activated protein kinase (PKR). This activation leads to eukaryotic initiation factor 2α (eIF2α) phosphorylation, resulting in the suppression of translation. Furthermore, by scrutinizing the PNPT1 recognition element and screening 17,728 drugs and bioactive compounds approved by the US Food and Drug Administration, lanatoside C was identified as a potent PNPT1 inhibitor. This compound impedes the propagation of adenovirus, murine cytomegalovirus and hepatovirus, and suppresses production of the severe acute respiratory syndrome coronavirus-2 spike protein. These discoveries shed light on a novel strategy to impede pan-viral propagation by activating the host cell mt-dsRNA-PKR-eIF2α signalling axis.


Assuntos
eIF-2 Quinase , Humanos , Animais , eIF-2 Quinase/metabolismo , eIF-2 Quinase/antagonistas & inibidores , eIF-2 Quinase/genética , Antivirais/farmacologia , Muromegalovirus/fisiologia , Muromegalovirus/efeitos dos fármacos , Camundongos , Fator de Iniciação 2 em Eucariotos/metabolismo , Replicação Viral/efeitos dos fármacos , RNA de Cadeia Dupla/genética , Adenoviridae/genética , Adenoviridae/efeitos dos fármacos , Fosforilação , SARS-CoV-2/efeitos dos fármacos
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