Electron Microscopy Research Articles

Quantitative proteomics analysis reveals the pathogenesis of obstructed defecation syndrome caused by abnormal expression of dystrophin

BACKGROUND Obstructed defecation syndrome (ODS) represents the most prevalent form of chronic constipation, affecting a diverse patient population, leading to numerous complications, and imposing a significant burden on healthcare resources. Most ODS patients have insufficient rectal propulsion, but the exact mechanism underlying the pathogenesis of ODS remains unclear. AIM To explore the molecular mechanism underlying the pathogenesis of ODS. METHODS A total of 30 pairs of rectal samples were collected from patients with ODS (ODS group) or grade IV prolapsed hemorrhoids without constipation (control group) for quantitative proteomic and bioinformatic analysis. Subsequently, 50 pairs of paraffin-embedded rectal specimens were selected for immunohistochemistry and immunofluorescence studies to validate the analysis results. Human intestinal smooth cell contractile function experiments and electrophysiological experiments were conducted to verify the physiological functions of target proteins. Cellular ultrastructure was detected using transmission electron microscopy. RESULTS In comparison to the control group, the expression level of dystrophin (DMD) in rectal specimens from ODS patients was markedly reduced. This finding was corroborated using immunohistochemistry and immunofluorescence techniques. The diminished expression of DMD compromised the contractile function of intestinal smooth muscle cells. At the molecular level, nucleoporin protein 153 and L-type voltage-gated calcium channel were found to be overexpressed in intestinal smooth muscle cells exhibiting downregulated DMD expression. Electrophysiological experiments confirmed an excessive influx of calcium ions into these cells. Moreover, vacuolar-like structures which may be associated with excessive calcium influx were observed in the cells by transmission electron microscopy. CONCLUSION Decreased DMD expression in intestinal smooth muscle may upregulate L-type voltage-gated calcium channel expression, leading to excessive calcium influx which may cause a decrease in rectal propulsion, thereby contributing to the pathogenesis of ODS.

Direct method for microscale manipulation at liquid-liquid interfaces in ionic liquid media with real-time electron microscopy observation

A deep understanding of the processes in soft matter systems with liquid-liquid phase boundaries is of particular importance for materials science, chemistry and life sciences. A vast variety of physicochemical techniques have been proposed for the study of interfacial properties of liquid systems. Among them, electron microscopy methods occupy an important place due to the possibility of direct observation of the sample areas of interest with high spatial resolution; however, the harsh conditions of the electron microscope chamber impose significant restrictions on the possibilities of observing and manipulating unprotected liquids and related soft systems. To overcome these difficulties, in this work, we developed a methodology for direct probing of liquid-liquid interfaces with simultaneous control of the process using electron microscopy. Practically relevant liquid mixtures based on vacuum-compatible ionic liquid (IL) with water additives were probed with micrometer accuracy in real time inside an electron microscope chamber, which made it possible to reveal the role of specific ions aggregation and electrostatic phenomena in the stabilization of liquid microdomains. To test the versatility of the proposed approach, the morphology of a typical IL/water mixture was examined using a series of electron microscopes of various configurations, and it was shown that the best level of contrast between two chemically related liquid phases can be obtained in the case of a cold field emission electron source in combination with an in-lens secondary electron detector, regardless of the specific instrument manufacturer.

Dihydrolipoamide acetyltransferase is a key factor mediating adhesion and invasion of host cells by Mycoplasma synoviae.

Mycoplasma synoviae is a significant avian pathogen responsible for chronic respiratory diseases, arthritis, and infectious synovitis in chickens and turkeys. These infections result in substantial economic losses to the global poultry industry. Dihydrolipoamide acetyltransferase (E2) is a multifunctional protein that plays an indispensable role in energy metabolism and redox balance and is also a key virulence factor of various pathogens. In this study, we used the avian pathogen M. synoviae as a model to identify the role of the E2 protein in the colonization and invasion of host cells. First, we prepared the polyclonal antibody of recombinant E2 (rE2) protein and found that the rE2 antibody had a strong complement-activating ability. E2 was found to be distributed in the cytoplasm and cell membrane of M. synoviae by immunoelectron microscopy. E2 localized on the cell membrane is a key factor in the adhesion of M. synoviae and has good immunogenicity. Enzyme-linked immunosorbent assay showed that the binding of rE2 to membrane proteins of chicken embryo fibroblasts (DF-1) was dose-dependent, and antiserum effectively inhibited this binding ability. Furthermore, E2 interacted with various components of the host extracellular matrix (ECM) and promoted the conversion of plasminogen to plasmin through terephthalic acid (tPA). In addition, E2 can enhance the ability of M. synoviae to invade DF-1 cells, which was significantly reduced after treatment with anti-E2 serum. These results indicate that E2 is an adhesion- and invasion-related protein and may be involved in the pathogenesis of M. synoviae, which provides new ideas for studying the pathogenesis of M. synoviae and preparing subunit vaccines.

Qualitative evaluations of reactive microglial heterogeneity in cultured porcine retina.

A late stage of several retinal disorders is retinal detachment, a complication that results in rapid photoreceptor degeneration and synaptic damage. The porcine retina is a favorable in vitro model for studies of the degenerative processes that follow retinal detachment. Photoreceptor degeneration and synaptic injuries develop rapidly in the cultured porcine retina and correlate with resident microglial cell transition into a reactive phenotype. In this in vitro study, we used retinas cultured for five days and analyzed reactive CD11b and Iba1 immunoreactive microglia that localized close to/within the synaptic outer plexiform layer (OPL) and in the outer nuclear layer (ONL). A subpopulation of the CD11b and Iba1immunoreactive microglia also expressed CD68 immunoreactivity on lysosomal membranes or as a diffuse cytoplasmic stain. Some CD68 immunoreactive microglia were juxtaposed to L/M-opsin immunoreactive cone photoreceptors in the ONL. CD11b and Iba immunoelectron microscopy further suggests the presence of a dark microglial phenotype in the degenerating cultured porcine retina. For immunoelectron microscopy, nickel-enhanced diaminobenzidine (DAB) staining resulted in clearly distinguished reaction products in the cytosol of dark microglia.

Investigating the thermal-chemical-mechanical coupling effects on the cracking behavior of machine gun barrel: Microstructural insights

The presence of severe cracks at the inner bore of the gun barrel accelerates the erosion failure, whereas the evolution and failure mechanism of crack tips under the thermal-chemical-mechanical coupling effects needs further investigation. Herein, the elemental distribution, phase structure, and strain surrounding the perpendicular and circumferential cracks in a failed gun barrel were investigated in detail by utilizing scanning electron microscopy (SEM), transmission Kikuchi diffraction (TKD), and transmission electron microscopy (TEM). Results indicated that the perpendicular crack was covered by double continuous layers composed of inner FeO oxides and outer Fe0.96S sulfides. Notably, a high-density precipitation of FeO oxides together with severe lattice distortion and localized amorphization was observed at the crack tip, accelerating the growth of the cracks. For the circumferential crack, the presence of fine recrystallized grains alongside coarsened M23C6 carbides was observed at the crack tip. There was a high level of strain concentration along high-angle grain boundaries at the forefront of the circumferential crack tip, resulting in the cracking along grain boundaries. Furthermore, the models for propagation of perpendicular and circumferential cracks under the thermal-chemical-mechanical coupling effects were proposed respectively.

Ni-In-oxalate nanostructure as electrode materials for high-performance supercapacitors

Energy storage technologies play a crucial role in addressing the intermittent characteristics of renewable energy sources, improving the stability of electrical grids, and decreasing the release of greenhouse gas emissions. In this study, we presented nickel indium oxalate (Ni1-xInxC2O4) as a promising material with potential applications in the field of electrochemical energy storage. The as-prepared Ni-In- oxalate sample was subjected to different physical characterizations, including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Regarding the electrochemical energy storage capability, the Ni1-xInxC2O4 electrode material exhibited a specific capacitance of 835 F g-1 (417.5 C g-1) at 1 A g-1. The incorporation of nickel into the indium oxalate nanoplates enhances their electrochemical performance. The presence of nickel in the nanoplates generated from substrate, improving the overall conductivity of the material and enhances its electrochemical reactions, thus leading to improved energy storage capabilities.

DeepMulticut: Deep Learning of Multicut Problem for Neuron Segmentation From Electron Microscopy Volume.

Superpixel aggregation is a powerful tool for automated neuron segmentation from electron microscopy (EM) volume. However, existing graph partitioning methods for superpixel aggregation still involve two separate stages-model estimation and model solving, and therefore model error is inherent. To address this issue, we integrate the two stages and propose an end-to-end aggregation framework based on deep learning of the minimum cost multicut problem called DeepMulticut. The core challenge lies in differentiating the NP-hard multicut problem, whose constraint number is exponential in the problem size. With this in mind, we resort to relaxing the combinatorial solver-the greedy additive edge contraction (GAEC)-to a continuous Soft-GAEC algorithm, whose limit is shown to be the vanilla GAEC. Such relaxation thus allows the DeepMulticut to integrate edge cost estimators, Edge-CNNs, into a differentiable multicut optimization system and allows a decision-oriented loss to feed decision quality back to the Edge-CNNs for adaptive discriminative feature learning. Hence, the model estimators, Edge-CNNs, can be trained to improve partitioning decisions directly while beyond the NP-hardness. Also, we explain the rationale behind the DeepMulticut framework from the perspective of bi-level optimization. Extensive experiments on three public EM datasets demonstrate the effectiveness of the proposed DeepMulticut.

Biosynthesis of ZnO nanocomposites from Mentha spicata applications of antioxidant, antimicrobial and genotoxicity advances in MCF-7 cell line

This study focuses on enhancing the, Spearmint (Mentha spicata), an aromatic herb indigenous to Europe and Asia, which is valued for its refreshing flavor and potential health benefits. This herb is widely utilized in culinary practices, medicinal applications, and cosmetic formulations. The ethanol extract derived from the M. spicata leaf contains is rich secondary metabolites with various bioactive properties: Specifically, such as tannins, flavonoids, and polyphenols are known for their antioxidant and anti-inflammatory effects, saponins help reduce cholesterol, and alkaloids have analgesic properties. The extract has a total flavonoid content (TFC) of 231.37 ± 2.05 mg GAE/g and a total phenol content (TPC) of 247.32 ± 5.07 mg GAE/g. Zinc oxide (ZnO) nanoparticles were synthesized from this extract and subsequently characterized through various analytical techniques. The absorbance measurement at 437 nm confirmed the successful nanoparticle synthesis. FTIR spectra showed water-related absorption bands at 3330 cm−1 and 3337 cm−1. Scanning electron microscopy (SEM) indicated the presence of spherical nanoparticles of about 25.4 nm, while transmission electron microscopy (TEM) illustrated particles ranging from 20 to 50 nm with high crystallinity and a lattice spacing of 0.297 nm. X-ray diffraction (XRD) analysis confirmed their crystalline structure with distinct Bragg reflections at 39.1°, 46.1°, 68.7°, and 79.2°, which corresponding to (111), (200), (220,311) planes, respectively (JCPDS card no. 01–080-1876). Energy-dispersive X-ray spectroscopy (EDX) confirmed the high purity of the synthesized ZnO nanocrystals. The nanoparticles demonstrated significant antioxidant activity with radical scavenging rates up to 97.33 %, effective antimicrobial properties, and notable anticancer activity, achieving 99.75 % inhibition of MCF-7 cells at 40 μg/mL. These findings highlight the nanoparticles' potential applications in health and medicine.

Synthesis of MnMoO4/α-MoO3 composite materials for supercapacitor

In the quest for developing supercapacitors with enhanced energy density, we have successfully synthesized MnMoO4/MoO3 composite materials tailored for supercapacitor applications. The synthesis process utilized (NH4)6Mo7O24·4H2O and MnCl2·4H2O as precursors. The resulting composite materials were thoroughly characterized using a suite of analytical techniques, including scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction analysis, Brunauer-Emmett-Teller surface area measurements, thermogravimetric analysis, and differential scanning calorimetry. Furthermore, the supercapacitive performance of the MnMoO4/α-MoO3 composite materials was evaluated using cyclic voltammetry and constant current charge–discharge methods. The synthesis yielded an ideal composite material, with low-resistance MnMoO4 seamlessly integrated with high ion-conductive MoO3. At a current density of 3 A/g, the specific capacitance was measured at 1878.7 F/g, achieving an energy density of 260.9 Wh kg−1 and a power density of 1.448 kW kg−1. The composite materials demonstrated significant potential for the production of high-density supercapacitors.

Facile bio-inspired fabrication of AgNPs from Salvia elegans leaf extract and determination of their cytotoxic DNA photocleavage potential

This study introduces a sustainable method for producing silver nanoparticles (AgNPs), focusing on sustainability and environmental protection. The technique includes the use of Salvia elegans aqueous leaf extract as a reducing agent. In addition, the research investigates the dose-dependent degradation of pUC19 DNA by silver nanoparticles, which is facilitated by the generation of singlet oxygen. The presence of S. elegans extract results in significant color changes, going from a colorless state to a dark brown hue, serving as an indication of the synthesis of AgNPs. A range of experimental methods were employed to analyze the biogenic silver nanoparticles, such as UV–visible absorption spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The meticulously produced AgNPs demonstrate a high level of uniformity, featuring a spherical shape and a particle size of 60 nm. DNA photo-cleavage studies show that singlet oxygen plays a crucial role in triggering DNA damage caused by AgNPs indicates their potential as powerful cytotoxic agents specifically aimed at cancer cells. Additional studies are required to clarify the effectiveness and specificity of AgNPs against various cancer cell types to assess their therapeutic potential. The cytotoxic effects of AgNPs, particularly in relation to DNA photocleavage, are of considerable interest in cancer research. This research holds promise for developing novel and sustainable cancer therapies based on the unique properties of biogenic silver nanoparticles.

Hydrolytic instability of laser-ablatively deposited CaSi2 coatings in air and neutral water affects the behavior of bone healing-related cell types

Calcium silicide (CaSi2) instability in humid air or pH-neutral water remains unknown, although the topochemical formation of silicene from CaSi2 in various aqueous phases is a well-known process. Here we report on laser ablation of CaSi2 in the vacuum and ethanol, characterize coatings deposited on titanium substrates with electron microscopy, X-ray photoelectron, Raman, and infrared spectroscopy, and examine the instability of the deposited coatings in humid air and neutral water. We further investigate the behavior of human mesenchymal stromal cells (hMSCs), vascular cells (HUVECS, human umbilical vein endothelial cells), and macrophages (derived from THP-1 cell line) in contact with the deposited coatings submerged in cell culture medium. The observed results indicate that the CaSi2 coatings undergo topochemical conversion to silicene, which is accompanied by hydrolytic reactions leading to inorganic Ca compounds and SiO2, and that the response of all cell types in the hydrolyzed CaSi2 surface domain is negatively affected by the nature of the hydrolytic products. In contrast, cells showed a tendency for enhanced biocompatibility towards the CaSi2 particles ablated in the vacuum. The results suggest that coating approaches can significantly influence cell behavior outcomes.

Antimicrobial effects of peptides from fenugreek and ginger proteins using Fe3O4@PDA-MWCNT conjugated trypsin by improving enzyme stability & applications

Trypsin was immobilized onto a newly formulated nanocomposite (NC) comprising magnetic (Fe3O4) multiwalled carbon nanotubes (MWCNTs) anchored with polydopamine (PDA). The fabricated NC and the NC-bound trypsin were subjected to comprehensive characterization using various biophysical techniques including Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and fluorescence spectroscopy. The NC-bound trypsin exhibited significantly enhanced thermostability and increased tolerance to various organic solvents and denaturants. The enzymatic activity of trypsin was notably augmented through its coupling with the nano support, yielding an effectiveness factor (η) of 2.65. Fenugreek and ginger protein hydrolysates, prepared using both native and NC-bound enzyme, were evaluated for their antimicrobial activities. The analysis revealed that peptides generated by NC-bound trypsin showed higher antimicrobial activity (~ 10) in most cases compared to peptides obtained by using native trypsin. This strategy presents an innovative methodology for the production of potential biopeptides, with the prospect of their incorporation into pharmaceutical and therapeutic sectors through the utilization of NC-bound trypsin in protein hydrolysis.

Direct observation of the evolution behavior of micro to nanoscale precipitates in austenitic heat-resistant steel via electron channeling contrast imaging

Precipitation directly determines the high-temperature properties of the austenitic heat-resistant steels. The precipitations of MX, Z-phase, M23C6 and σ-phase, ranging from micrometers to nanometers, are commonly characterized using the scanning electron microscopy (SEM) and transmission electron microscopy (TEM). However, details of their evolution behavior are still unclear due to the limited SEM resolution using the traditional sampling method and the limited spatial resolution of TEM. In this work, field emission SEM-based electron channel contrast imaging (ECCI) techniques with flexible sampling routes were introduced to observe the precipitation evolution behavior of HR3C steel after aging at 700 °C for 8095 h. We showed that the coarse primary-MX and Z-phase in the as-received steel are relatively stable during aging. The coarse M23C6 and tiny secondary Z-phase dispersions were rapidly formed along the grain/twin boundaries and within dislocation arrays inside the grain interior, respectively. We further found that the M23C6 at grain boundaries would change from continuous to semi-continuous due to the formation of σ-phases, while in twin boundaries, it would become continuous over aging. Moreover, we showed that the σ-phases were in-situ transformed from M23C6 at the grain boundaries via its dissolution, facilitating the nucleation of tiny Z-phase inside the σ-phase grains, and this phenomenon has not been reported so far. We have demonstrated that ECCI with an electrolytic-polishing-based sampling route is effective in revealing multi-scale precipitation with high-throughput efficiency, and it allows the direct observation of the complex behavior of precipitates down to the nanoscale using a bulk sample. This method can be used as an efficient way for the quantitative microstructure study.

Influence of Ti element on the microstructure and crack of modulated WC-strengthened Ni-based alloy coatings by laser cladding

For laser cladding of WC reinforced Ni50A Ni-based alloy coatings can cause cracks and porosity. Cracks and pores will restrict the application and performance of the coating. In order to improve the crack condition of the coating, the influence of alloying element Ti on the crack was investigated by introducing it. Cracks in the coatings were eliminated. When the addition amount of Ti is 3wt%, the morphology and properties of the coating are the best. The phase composition, microstructure, elemental distribution and grain orientation of the coatings were characterised using X-ray Diffractometry (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectrometer (EDS), Electron Backscatter Diffraction (EBSD) and Transmission Electron Microscopy (TEM). The hardness and abrasion resistance of the coatings were tested using microhardness tester and friction tester. The results show that a large number of second phases are present in the coating when Ti particles are not added. The introduction of Ti element disperses the localised stresses in the Ni50A-WC coating. The macroscopic morphology of Ni50A-WC coating was improved. The introduction of Ti reduced the area of the second phase within the coating. The introduction of Ti generated TiC/TiWC2 in situ. However, the introduction of Ti increased the dilution rate and decreased the strength of the coating. Therefore, the microstructure of the coating can be controlled and the macroscopic defects of the coating can be improved by adjusting the addition ratio of Ti elements.

Influence of particle deformation zone (PDZ) size on dynamic recrystallization and precipitation behavior of SiCp/Mg-5Zn material during hot compression

The influence of particle deformation zone (PDZ) size on dynamic recrystallization (DRX) and precipitation behavior of SiCp/Mg-5Zn material was investigated through the hot compression. First, the microstructure and microhardness of matrix in PDZ were characterized for SiCp/Mg after compression at room temperature. Then, the microstructure evolution of SiCp/Mg-5Zn materials with different PDZ size was analyzed by optical microscopy (OM), scanning electron microscopy (SEM), electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) after compressing different strains. The results show that a significant misorientation gradient was formed near the particle for SiCp/Mg after compression at room temperature, but which is smaller than that around the grain boundary. The addition of SiCp can promote DRX nucleation of Mg matrix, but the promotion effect of particles on DRX nucleation is less than that of grain boundaries for SiCp/Mg-5Zn material during the hot compression, which causes a decrease in the DRXed ratio of SiCp/Mg-5Zn material with increasing PDZ size. Moreover, the volume fraction and size of precipitated phase both decrease with increasing the PDZ size. The aim of this work is to provide a strategy to acquire Mg alloys with excellent mechanical performance by regulating the microstructure of Mg matrix.

Development of rare earth doped SiO2/rGO from rice husk for antioxidant, photocatalysis, electrochemical and sensor studies

The present work determines the synthesis of cerium loaded silicon dioxide (Ce-SiO2/rGO) nanocomposite by using reflux method. The Ce-SiO2/rGO was confirmed by using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive (EDAX) techniques. In photodecomposition investigation, Rose Bengal (RB) dye was degraded efficiently using Ce-SiO2/rGO nanocomposite (95 %) at 150 min with follows first order kinetics. The antioxidant property against 2,2-diphenyl-1-picrylhydrazyl (DPPH) was found to be 98 % performance with IC50 value of 488.35 mg/mL. The super capacitance value of Ce-SiO2/rGO was increased compared to that of rGO, SiO2 and SiO2/rGO respectively. The electrochemical reversibility (EO−ER) and diffusion coefficient (D) values were determined using 1 M KCl by cyclic voltammetry method. Ce-SiO2/rGO nanocomposite was used as an electrochemical sensor to detect bee pollen and cow urine. The produced material has superior dye purification, redox behavior, bio-molecule detection, and antioxidative capabilities.

Green synthesis of silver nanoparticles from supercritical CO2 mediated Lagerstroemia speciosa extract: Characterization, antimicrobial and antibiofilm activity

In the current study, optimal supercritical fluid extract (SFE) of Lagerstroemia speciosa (LS) leaves at pressure 29.59 megapascal (MPa), temperature 89.50 ºC and extraction time 53.85 min. was used to extract phenolic compounds for the synthesis of silver nanoparticles (AgNPs). The synthesis was studied for 0-20 hrs. Initially the synthesis of nanoparticles (SFELS-AgNPs) was confirmed using UV -spectroscopy. It demonstrated a maximum surface plasmon resonance at 430 nm. The crystallite dimension of nanoparticles was determined using X-ray diffraction (XRD) (13.47 nm), Transmission electron microscopy (TEM), zeta potential analysis and energy-dispersive X-ray analysis (EDAX) were used to analyze the morphology, surface charge and presence of differential elements in SFELS-AgNPs respectively. Developed nanoparticles revealed antimicrobial activity against two gram-positive viz. Staphylococcus aureus and Bacillus cereus, and three gram-negative bacteria viz. Klebsiella pneumonia, Pseudomonas aeruginosa and Escherichia coli. The nanoparticle showed a minimum inhibitory concentration (MIC) of 64 μg/ml whereas the minimum bactericidal concentration (MBC) 128 μg/ml against K. pneumonia. They significantly inhibited K. pneumonia biofilm formation which was confirmed using scanning electron microscopy (SEM). The results were encouraging compared to the standards drug Chloramphenicol and other controls. The generated nanoparticles have highly effective antimicrobial properties against pathogenic bacteria.

Exploring the mechanism of Ling-Gui-Zhu-Gan decoction in metabolic cardiomyopathy via inhibiting ferroptosis

ObjectiveThis study was to investigate the mechanism of Ling-Gui-Zhu-Gan decoction (LGZGD) in regulating lipid metabolism and thus inhibiting ferroptosis. MethodsUPLC for the determination of the main chemical composition of LGZGD. A HF-induced rat model of metabolic cardiomyopathy was established. Echocardiography was used to detect cardiac function. Serum lipid levels, myocardial injury markers, and lipid peroxidation levels were detected. Pathological changes were detected. Lipid deposition was assessed by oil red O, and the mitochondrial ultrastructure was observed by electron microscopy. Mechanistically, PLIN5, CD36, ATGL, GPX4, ACSL4, FPN1, DRP1, MFF, FIS1, and OPA1 expressions were examined. After PA-induced H9c2 cells established, apoptosis, myocardial injury markers, and lipid peroxidation levels were detected and lipid deposition levels were assessed. The expressions of PLIN5, CD36, ATGL, GPX4, ACSL4 and FPN1 were detected. H9c2 cardiomyocytes with transient knockdown of PLIN5 and overexpression of PLIN5 were constructed and treated with drug administration and modeling, and the apoptosis level was detected by flow cytometry, the levels of lipid peroxidation and ROS were detected by fluorescence, and the protein and gene expressions of ACSL4 and GPX4 were detected. Results The main active components of LGZGD were liquiritin, isoliquiritin, cinnamic acid, cinnamaldehyde, glycyrrhizic acid, and atractylenolide III. LGZGD significantly improved cardiac dysfunction, lowered lipid level and lipid deposition, reduced CK, NT-proBNP and MDA levels, restored SOD levels, and improved inflammatory cell infiltration as well as collagen fiber deposition. LGZGD decreased the expression of PLIN5, CD36, ACSL4, and increased the expression of ATGL, GPX4, and FPN1. LGZGD also decreased the gene expression of DRP1, MFF, FIS1, and increased OPA1 expression. LGZGD significantly ameliorated PA-induced apoptosis, decreased lipid deposition, lowered lipid peroxidation levels and CK level, decreased PLIN5, CD36, and ACSL4 expressions, and increased ATGL, GPX4, and FPN1 expressions. LGZGD reversed cardiomyocyte injury aggravated by transient knockdown of PLIN5, decreased apoptosis levels, lipid peroxidation levels, ROS levels, and ACSL4 expressions, and increased GPX4 expression. LGZGD enhanced cardiomyocyte protection after overexpression of PLIN5, reduced apoptosis levels, lipid peroxidation level and ROS level, decreased ACSL4 expression, and increased GPX4 expression. ConclusionPLIN5 interferes with lipid peroxidation, regulates mitochondrial function, and inhibits HF-induced ferroptosis in cardiomyocytes. LGZGD ameliorates impairment of cardiac structural function in model rats through PLIN5-mediated ferroptosis pathway, and has the effect of preventing metabolic cardiomyopathy.

Polythiophene/Copper Vanadate Nanoribbons and their Electrochemical Sensing Properties for Detecting Benzoic Acid

Background: Excessive intake of benzoic acid may cause serious diseases, including disordered metabolism, abdominal pain, and diarrhea. Hence, it is important to explore a reliable method to determine the quantity of benzoic acid for protecting human health. In this regard, polythiophene/ copper vanadate nanoribbon composites act as electrode materials for the detection of benzoic acid. Objective: The objective of this research was to synthesize polythiophene/copper vanadate nanoribbons via an in-situ polymerization approach and evaluate their electrochemical performance for the detection of benzoic acid. Methods: Polythiophene/copper vanadate nanoribbons were obtained via an in-situ polymerization approach. The obtained composite nanoribbons were analyzed using X-ray diffraction, electron microscopy, Fourier Transform Infrared Spectroscopy, and electrochemical method. Results: Amorphous polythiophene nanoparticles with a size of less than 100 nm were homogeneously attached to the copper vanadate nanoribbons. Electrochemical sensing properties of the polythiophene/ copper vanadate nanoribbons modified electrode for detecting benzoic acid were analyzed using the Cyclic Voltammetry (CV) method. An irreversible CV peak was observed at +0.36 V in 0.1 M KCl solution with 2 mM benzoic acid. The polythiophene/copper vanadate nanoribbons modified electrode indicated a linear range of 0.001-2 mM with the limit of detection (LOD) of 0.29 μM. Conclusion: Polythiophene greatly enhanced the electrochemical sensing properties of copper vanadate nanoribbons. Polythiophene/copper vanadate nanoribbons modified electrode was found to be stable and repeatable owing to the synergistic effect of various components.

Molecularly imprinting polymethacrylamide onto Cu-based metal-organic framework as a pH-sensitive core-shell nanocarrier for potential anti-cancer drug delivery.

Surface molecularly imprinted polymers (MIPs) are an efficient and rapidly advancing approach, increasingly being utilized in drug delivery systems (DDSs). This research involved synthesizing a core-shell structure, consisting of a metal-organic framework (MOF) core and a doxorubicin (DOX) imprinted polymethacrylamide shell, prepared via precipitation polymerization method in green media. The resulting MOF@MIP was utilized as a nanocarrier for DOX delivery, exhibiting high drug loading capacity and pH responsiveness delivery. The materials were characterized using different techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), fourier transform infrared (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS), thermal gravimetric analysis (TGA), and zeta potential (ZP). In vitro studies on DOX loading and release demonstrated that a higher amount of DOX was released in a sustained manner under tumor tissue conditions (pH 5, 41 °C) compared to normal physiological conditions (pH 7.4, 37 °C). Additionally, cytotoxicity evaluations revealed significant cytotoxic effects of DOX-loaded MOF@MIP on MCF-7 cells (IC50: 2 μg/mL). Based on these findings, the synthesized MOF@MIP shows promise as a potential candidate for the development of anticancer therapeutic delivery platforms.