Electron Microscopy Research Articles

Sustainable Removal of Phenol from Aqueous Media by Activated Carbon Valorized from Polyethyleneterephthalate (PET) Plastic Waste

PET, one of the most commonly used plastics, presents significant environmental challenges due to its non-biodegradable nature. To address this, we developed a sustainable method to convert PET waste into high-performance activated carbon via chemical activation with phosphoric acid (H3PO4). The produced activated carbon was analyzed utilizing X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), nitrogen adsorption/desorption (BET), energy-dispersive X-ray (EDX), and Raman spectroscopy. The activated carbon produced had a macroporous architecture with a substantial surface area, pore diameter, and pore volume of 655.59 m2/g, 3.389 nm, and 0.120 cm3/g, respectively. The adsorption isotherm of activated carbon for phenol conformed to the Langmuir model, signifying single-layer adsorption with a maximal capacity of 114.94 mg/g, while the kinetic adsorption adhered to the second-order model at an optimal pH of 7. The study highlights the sustainable benefits of mitigating plastic waste pollution while producing a cost-effective and eco-friendly adsorbent for water treatment applications. This research underscores the potential for recycling PET waste into valuable materials for environmental remediation.

High AC field-induced polarization switching unraveled in frequency domain: Enhanced dielectric responses in lanthanum-doped Pb(Ni1/3Nb2/3)O3-Pb(Zr,Ti)O3 relaxor-ferroelectrics

In this study, we delve into the complex dielectric behaviors of lanthanum (La)-doped PNN-PZT relaxor-ferroelectric ceramics under the influence of high AC fields. Our approach involves a meticulous design of dielectric measurements to scrutinize the decoupling phenomenon between local polarization oscillation and global polarization switching. Remarkably, the application of high AC fields (>0.5 kV/mm) causes a dramatic increase in the dielectric permittivity (2x), alongside pronounced frequency dispersion (>65 °C) and a permittivity hump below Tm in 7% La-doped relaxor compositions. For relaxor-ferroelectric ceramics doped with lower La (<=5%) that are featured with tweed-like submicron domains as imaged in in situ transmission electron microscopy, the significantly enhanced dielectric permittivity and dielectric loss (>1) are induced under high AC fields (<0.5 kV/mm). A comparative study with a polarization loop in the time domain under various AC fields and DC bias demonstrates that the dielectric anomaly in the frequency domain is associated with global polarization switching, co-existing with polarization oscillation mechanism in various domains. This frequency domain method reveals threshold AC fields (0.25–0.5 kV/mm) above which polarization switching occurs in relaxor-FE compositions at elevated temperatures, complements the dynamic behaviors of P–E hysteresis, and cautions the control of AC fields in dealing with relaxor-ferroelectric materials for advanced electronic applications.

Water hyacinth conversion to biochar for soil nutrient enhancement in improving agricultural product

The conversion of water hyacinth into biochar offers a sustainable solution to mitigate its proliferation and enhances its potential as a soil amendment for agriculture. This study examined the physicochemical properties of water hyacinth biochar (WHBC) and its impact on soil fertility. Water hyacinth (Eichhornia crassipes) was pyrolyzed at 300 °C for 40 minute with restricted airflow (2–3 m/s), producing biochar with desirable properties and a yield of 44.6%. WHBC exhibited a pH of 8.11 ± 0.91, electrical conductivity of 18.70 ± 1.15 mS/cm, and nutrient contents including TN (0.69 ± 0.10%), TP (8.80 ± 0.01%), OC (13.95 ± 0.65%), C/N ratio (20.22 ± 0.95), S (0.34 ± 0.03%), and metallic nutrients (Ca, Mg, K). Heavy metals (Fe, Mn, Cu, Ni, Cd, Pb, Cr, Zn) were within permissible limits for biochar. Soil amended with 2500 kg/ha WHBC (BC2) produced comparable Teff crop yields (fresh mass: 1191.67 ± 428.44 g, dry mass: 700.00 ± 248.34 g, grain yield: 95.00 ± 39.69 g) to those with mineral fertilizers and mixed amendments. Fourier Transform Infrared (FTIR) and Scanning Electron Microscopy (SEM) revealed significant structural changes in WHBC, enhancing its pore structure and surface morphology. These results demonstrate the potential of WHBC as an effective soil amendment to improve agricultural sustainability and soil fertility.

Unraveling 3d Transition Metal (Ni, Co, Mn, Fe, Cr, V) Ions Migration in Layered Oxide Cathodes: A Pathway to Superior Li-Ion and Na-Ion Battery Cathodes.

Li-ion and Na-ion batteries are promising systems for powering electric vehicles and grid storage. Layered 3d transition metal oxides AxTMO2 (A = Li, Na; TM = 3d transition metals; 0<x≤2) have drawn extensive attention as cathode materials due to their exceptional energy densities. However, they suffer from several technical challenges caused by crystal structure degradation associated with TM ions migration, such as poor cycling stability, inferior rate capability, significant voltage hysteresis, and serious voltage decay. Aiming to tackle these challenges, this review provides an in-depth discussion and comprehensive understanding of the TM ions migration behaviors in AxTMO2. First, the key thermodynamics and kinetics that impact TM ions migration are discussed, covering ionic radius, electronic configuration, crystal structure arrangement, and migration energy barrier. In particular, details are provided regarding the universal and specific migration characteristics of Ni, Co, Mn, Fe, Cr, and V ions in layered cathode materials. Subsequently, the impacts of these migrations on electrochemical performance are emphasized in terms of the fundamental science behind technical issues, and strategies to modulate TM ions migration for advanced cathode materials development are summarized. Besides, characterization techniques for probing the TM ions migration are present, like neutron diffraction (ND), scanning transmission electron microscopy (STEM), nuclear magnetic resonance (NMR), and others. Finally, future directions in this regard are comprehensively concluded. This review offers valuable insights into the basic design of advanced layered oxide cathode materials for Li-ion and Na-ion batteries.

Influence of Photoemission Geometry on Timing and Efficiency in 4D Ultrafast Electron Microscopy.

Broader adoption of 4D ultrafast electron microscopy (UEM) for the study of chemical, materials, and quantum systems is being driven by development of new instruments as well as continuous improvement and characterization of existing technologies. Perhaps owing to the still-high barrier to entry, the full range of capabilities of laser-driven 4D UEM instruments has yet to be established, particularly when operated at extremely low beam currents (~fA). Accordingly, with an eye on beam stability, we have conducted particle tracing simulations of unconventional off-axis photoemission geometries in a UEM equipped with a thermionic-emission gun. Specifically, we have explored the impact of experimentally adjustable parameters on the time-of-flight (TOF), the collection efficiency (CE), and the temporal width of ultrashort photoelectron packets. The adjustable parameters include the Wehnelt aperture diameter (DW), the cathode set-back position (Ztip), and the position of the femtosecond laser on the Wehnelt aperture surface relative to the optic axis (Rphoto). Notable findings include significant sensitivity of TOF to DW and Ztip, as well as non-intuitive responses of CE and temporal width to varying Rphoto. As a means to improve accessibility, practical implications and recommendations are emphasized wherever possible.

Development of Novel Monolithic Catalyst for BTEX Catalytic Oxidation Using 3D Printing Technology

Four differently shaped monolithic catalyst supports were made using 3D printing technology. Two catalytically active mixed oxides, MnFeOx and MnCuOx, were applied to the monolithic supports using the impregnation technique. Catalysts were characterized using an adhesion test, field emission scanning electron microscopy, X-ray diffraction, and Raman spectroscopy in a manner similar to the density functional theory model. Excellent mechanical stability of the catalyst layer was obtained, with catalyst mass loss under 2% after 30 min of ultrasound exposure. SEM analysis revealed that the catalyst layer was rough but homogeneous in appearance and ~6 μm thick. The presence of double oxides—FeMnO3 and CuMn2O4—as well as single oxides of Mn, Fe, and Cu was established via XRD and Raman spectroscopy. Additional theoretical calculations of Raman spectra for FeMnO3 and CuMn2O4 were performed in order to aid in the interpretation of Raman spectra. The catalytic activity of the prepared catalysts for the catalytic oxidation of a gaseous mixture of benzene, toluene, ethylbenzene, and o-xylene (BTEX) was investigated. The monolithic support with the most complex shape and, consequently, the greatest surface area proved to enable the highest efficiency, while both catalysts performed well having similar conversions.

Correlation Between Conductivity and Oxygen Evolution Reaction Activity in Perovskite Oxides CaMnO3-δ, Ca0.5Sr0.5MnO3-δ and SrMnO3-δ

The perovskite oxides CaMnO3-δ, Ca0.5Sr0.5MnO3-δ, and SrMnO3-δ were synthesized in air using a solid-state method, and their structural, electrical, and electrocatalytic properties were studied in relation to their oxygen evolution reaction (OER) performance. Iodometric titration showed δ values of 0.05, 0.05, and 0.0, respectively, indicating that Mn is predominantly in the 4+ oxidation state across all materials, consistent with prior reports. Detailed characterization was performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), iodometric titration, and variable-temperature conductivity measurements. Four-point probe DC measurements revealed that CaMnO3-δ (δ = 0.05) has a semiconductive behavior over a temperature range from 25 °C to 300 °C, with its highest conductivity attributed to polaron activity. Cyclic voltammetry (CV) in 0.1 M KOH was employed to assess OER catalytic performance, which correlated with room-temperature conductivity. CaMnO3-δ exhibited superior catalytic activity, followed by Ca0.5Sr0.5MnO3-δ and SrMnO3-δ, demonstrating that increased conductivity enhances OER performance. The conductivity trend, CaMnO3-δ &gt; Ca0.5Sr0.5MnO3-δ &gt; SrMnO3-δ, aligns with OER activity, underscoring a direct link between electronic transport properties and catalytic efficiency within this series.

Evaluation of the Effect of Different Universal Adhesives on Remineralized Enamel by Shear Bond Strength and Fe-SEM/EDX Analysis

The aim of this study is to evaluate the shear bond strength of different universal adhesives applied to intact, demineralized, and remineralized enamel surfaces with total-etch and self-etch modes and to examine the effect of universal adhesives on the Ca/P mineral atomic and mass ratios of these enamel with FE-SEM/EDX (Field Emission Scanning Electron Microscopy with Energy Dispersive X-Ray Spectroscopy) analysis. For this study, 264 bovine incisors were used. Samples in the demineralized and remineralized groups were kept in demineralization solution at 37 °C for 96 h to make an artificial initial carious lesion. After demineralization, half of the demineralized samples were remineralized with MI Paste Plus. For shear bond strength (n = 144) and FE-SEM/EDX analysis (n = 120), G-Premio Bond and Clearfil S3 Bond Universal were applied on enamel surfaces with total-etch and self-etch modes, and bond strength samples were restored with resin composite. All samples were tested. The results were evaluated statistically by a three-way ANOVA test. The shear bond strength of the remineralized enamel showed high bond strength values comparable to intact enamel for universal adhesive systems. The Ca/P mineral atomic and mass ratios in remineralized enamel showed higher values than demineralized enamel, similar to intact enamel for universal adhesive systems. Initial carious lesion surfaces are unsuitable enamel surfaces for restoration. The remineralization of this surface layer before adhesive procedures may positively affect bond strength.

Crystal growth, structural phase transitions and optical gap evolution of FAPb(Br1-xClx)3 hybrid perovskites (FA: formamidinium ion, CH(NH2)2+)

Chemically tuned organic–inorganic hybrid halide perovskites based on bromide and chloride anions CH(NH2)2Pb(Br1−xClx)3 (CH(NH2)2+: formamidinium ion, FA) have been crystallized and investigated by neutron powder diffraction (NPD), single crystal X-ray diffraction (SCXRD), scanning electron microscopy (SEM) and UV–vis spectroscopy. FAPbBr3 and FAPbCl3 experience successive phase transitions upon cooling, lowering the symmetry from cubic to orthorhombic phases; however, these transitions are not observed for the mixed halide phases, probably due to compositional disorder. The band-gap engineering brought about by the chemical doping of FAPb (Br1-xClx)3 perovskites (x = 0.0, 0.33, 0.5, 0.66 and 1.0) can be controllably tuned: the gap progressively increases with the concentration of Cl− ions from 2.17 to 2.91 eV at room temperature, presenting a nonlinear behavior. This study provides an improved understanding of the structural and optical properties of these appealing hybrid perovskites.

Microstructure and Mechanical Behavior of Magnetron Co-Sputtering MoTaN Coatings

In recent years, there have been important developments in the refractory metal nitride coatings used for versatile applications, such as MoN, TaN, NbN, etc. Engineered approaches, including the deposition method, microstructure control, structural design, and the addition of functional elements, are put into practice for the promotion of coating characteristics. This study focuses on the microstructure and mechanical properties of ternary molybdenum tantalum nitride, MoTaN, coatings. MoTaN was deposited using a reactive radio frequency (r.f.) magnetron co-sputtering system with Mo/Ta target input power modulation control. The effects of composition and microstructure variations on its mechanical properties, including its hardness, elastic modulus, and wear behavior, were investigated. In general, the MoTaN coatings exhibited a columnar polycrystalline microstructure with MoN(111), Mo2N(111), Mo2N(200), TaN(200), and TaN(220) phases and orientations based on X-ray diffraction analysis. The addition of Ta triggered the transition of the primary orientation of Mo2N(111) into Mo2N(200). Transmission electron microscopy was utilized to analyze the transformation of the multiphase structure and changes in the grain size in terms of the Ta addition. According to nanoindentation and wear resistance analyses, superior hardness, elastic modulus, H/E, H3/E2, and wear-resistance values were identified for the MoTaN coatings with 6.8 to 10.4 at.% Ta, and a maximum hardness of 18.0 GPa was found for the MoTaN coating deposited at an input power of Mo/Ta = 150/100 W/W. An optimized hardness of 18.0 GPa and an elastic modulus of 220.7 GPa were obtained. The adjustment of the input power during deposition played a critical role in determining the overall performance of the MoTaN co-sputtering coatings. The MoTaN coating with optimized mechanical properties is attributed to its multiphase microstructure and fine columnar grain size of less than 30 nm.

Lattice Multislice Algorithm for Fast Simulation of Scanning Transmission Electron Microscopy Images.

We introduce a new approach to the numerical simulation of Scanning Transmission Electron Microscopy images. The Lattice Multislice Algorithm takes advantage of the fact that the electron waves passing through the specimen have limited bandwidth and therefore can be approximated very well by a low-dimensional linear space spanned by translations of a well-localized function. Just like in the PRISM algorithm recently published by C. Ophus, we utilize the linearity of the Schrödinger equation but perform the approximations with functions that are well localized in real space instead of Fourier space. This way, we achieve a similar computational speedup as PRISM, but at a much lower memory consumption and reduced numerical error due to avoiding virtual copies of the probe waves interfering with the result. Our approach also facilitates faster recomputations if local changes are made to the specimen such as changing a single atomic column.

"Theory of Pore Conflation" and "Shubhjyot's equation" in the treatment of Brilliant green dye-contaminated water using Jamun leaves biochar

This study investigates the adsorption of Brilliant Green (BG) dye onto biochar derived from Syzygium cumini (Jamun) leaves (JLB). Biochar was produced via pyrolysis at 800 °C and examined employing various methods, including Scanning electron microscopy (SEM–EDX), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) analysis, Raman spectroscopy, Zeta potential and X-ray photoelectron spectroscopy (XPS). The optimum parameters for BG dye adsorption, determined by batch adsorption studies, were a temperature of 80 °C, an initial dye concentration of 500 mg L−1, a contact period of 30 min, and an agitation speed of 400 RPM. The maximum adsorption capacity of JLB for BG was 243.90 mg g−1. It was found that the adsorption process adhered to the Freundlich isotherm model and pseudo-second-order kinetics, revealing heterogeneous adsorption with chemisorption. A novel "Theory of Pore Conflation" was proposed to explain enhanced adsorption at higher temperatures, supported by SEM and FTIR analyses. Additionally, a new equation termed "Shubhjyot's equation" was introduced to account for time dependency in adsorption capacity calculations. The thermodynamic analysis demonstrated that the process is endothermic and spontaneous. Isopropanol was the most effective organic solvent for desorption studies, demonstrating biochar regeneration potential for up to five cycles. Phytotoxicity and cyto-genotoxicity assessments demonstrated the environmental safety of JLB compared to BG dye. The use of JLB production offers a way to repurpose agricultural waste, contributing to circular economy principles. This extensive study demonstrates JLB's promise as an effective, economical, and environmentally safe adsorbent for wastewater treatment that eliminates textile dyes.Graphical

Targeted Activation of OGG1 Inhibits Paraptosis in Lens Epithelial Cells of Early Age-Related Cortical Cataract.

To investigate potential modes of programmed cell death in the lens epithelial cells (LECs) of patients with early age-related cortical cataract (ARCC) and to explore early-stage intervention strategies. Anterior lens capsules were collected from early ARCC patients for comprehensive analysis. Ultrastructural examination of LECs was performed using transmission electron microscopy. Cell death-associated protein markers were quantified via Western blot analysis, including those for paraptosis (ALIX, GRP78), apoptosis (cleaved caspase 3 and caspase 9), pyroptosis (N-GSDMD), and ferroptosis (GPX4). Intracellular vesicle-organelle colocalization was assessed through immunofluorescence. OGG1 protein expression and activity were evaluated through multiple methods, including Western blot, laser micro-irradiation, and immunofluorescence. The therapeutic potential of the OGG1 activator TH10785 on paraptosis was investigated using an ex vivo rat lens model. Morphologic changes revealed significant endoplasmic reticulum (ER) swelling in ARCC patient LECs, with no characteristic apoptotic features. Paraptosis-related proteins exhibited significant alterations, while other cell death pathway markers (apoptosis, pyroptosis, and ferroptosis) remained unchanged. In the reactive oxygen species-induced paraptosis model, vesicular structures showed exclusive colocalization with ER-specific fluorescence. Elevated levels of the DNA damage marker 7,8-dihydro-8-oxoguanine were observed concurrent with decreased OGG1 activity. The OGG1 activator TH10785 showed efficacy in suppressing LECs paraptosis in ex vivo rat lens cultures. Paraptosis was identified in the LECs of patients with early ARCC. TH10785 activates OGG1 to suppress paraptosis in LECs, suggesting a novel therapeutic approach for early ARCC intervention.

Solid-State Reaction Synthesis of CoSb2O6-Based Electrodes Towards Oxygen Evolution Reaction in Acidic Electrolytes: Effects of Calcination Time and Temperature

Mitigating global warming necessitates transitioning from fossil fuels to alternative energy carriers like hydrogen. Efficient hydrogen production via electrocatalysis requires high-performance, stable anode materials for the oxygen evolution reaction (OER) to support the hydrogen evolution reaction (HER) at the cathode. Developing noble metal-free electrocatalysts is therefore crucial, particularly for acidic electrolytes, to avoid reliance on scarce and expensive metals such as Ir and Ru. This study investigates a low-cost, solvent-free solid-state synthesis of CoSb2O6, focusing on the influence of calcination time and temperature. Six samples were prepared and characterized using powder X-ray diffraction (PXRD), energy-dispersive X-ray spectroscopy (EDX), Brunauer–Emmett–Teller (BET) analysis, field-emission scanning electron microscopy (FESEM), and electrochemical techniques. A non-pure CoSb2O6 phase was observed across all samples. Electrochemical testing revealed good short-term stability; however, all samples exhibited Tafel slopes exceeding 200 mV dec−1 and overpotentials greater than 1 V. The sample calcined at 600 °C for 6 h showed the best performance, with the lowest Tafel slope and overpotential, attributed to its high CoSb2O6 content and maximized {110} facet exposure. This work highlights the role of calcination protocols in developing Co-based OER catalysts and offers insights for enhancing their electrocatalytic properties.

Green Synthesis of Zinc Oxide Nanoparticles Including Rosehip (Rosa canina L.) Seed Extract: Evaluation of Its Characterization and Bioactivity Properties.

The use of bioactive compounds in plants as reducing, stabilizing, and capping agents in nanoparticle manufacturing is an exceptionally eco-friendly approach. This work used rosehip seed extract, acquired by automatic solvent extraction, in the microwave-assisted green production of zinc oxide nanoparticles (ZnO NPs). The total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity of the extracted materials and nanoparticles (NPs) were assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. The ideal synthesis parameters were established as 25mL of extract, pH 12, 360W of microwave power, and a metal salt concentration of 0.05M for a duration of 7min. The characterization of the ZnO NPs synthesized under these conditions was performed using x-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy with energy-dispersive x-ray analysis (SEM-EDX), dynamic light scattering (DLS), zeta potential measurements, and UV-Vis spectrophotometry. High-purity, nano-sized, antioxidant ZnO NPs were manufactured using an ecologically friendly, sustainable, and ecological technique.

Biodiesel Production from Animal Fats Using Blast Furnace Geopolymer Heterogeneous Catalyst: Optimisation and Kinetic Study

Abstract Biodiesel is a sustainable fuel alternative that is typically produced through a transesterification process that primarily employs homogeneous catalysts. However, they generate significant amounts of wastewater and are often non-\recyclable. This study aims to investigate the application of heterogeneous blast furnace slag geopolymer catalyst for biodiesel production from animal fat. Central composite design was employed to optimise the transesterification process, considering four key variables: the methanol-to-oil ratio (20–50 wt.%), reaction time (3–7 h), reaction temperature (30–70 °C) and catalyst-to-oil ratio (3–15 wt.%). The heterogeneous geopolymer catalyst was characterised using Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction. These analyses confirmed the geopolymerisation of the blast furnace slag and revealed no modifications to the geopolymer structure following the transesterification reaction. RSM optimisation resulted in 97.436% biodiesel yield, which was achieved at a constant stirring rate of 450 RPM, a reaction time of 6.254 h, a catalyst ratio of 9.996 wt.%, a methanol-to-animal fat ratio of 33.435 wt.%, and a reaction temperature of 50.509 °C, which was experimentally validated. The transesterification process followed pseudo-first-order reaction kinetics, with an activation energy of 43.76 kJ/mol. These findings demonstrate the potential of animal fat as a low-cost feedstock for biodiesel production catalysed by blast furnace slag geopolymer, offering a more sustainable and environmentally friendly alternative to traditional homogeneous catalysts.

A guide to CNN-based dense segmentation of neuronal EM images.

Large-scale reconstitution of neuronal circuits from volumetric electron microscopy images is a remarkable research goal in neuroanatomy. However, the large-scale reconstruction is a result of automatic segmentation using convolutional neural networks (CNNs), which is still challenging for general researchers to perform. This review focuses on two representative CNNs for dense neuronal segmentation: flood-filling networks (FFN) and local shape descriptors (LSD)-predicting U-Net (LSD network). It outlines their basic mechanisms, requirements, and output segmentation using author's example segmentation. The FFN excels in segmenting long axons, and the LSD network is adept at segmenting myelinated axons. The choice between FFN and LSD depends on the target, as neither is universally superior. A common limitation of FFN and LSD is the easy detachment of thin spines from parent dendrites, which is fundamentally unavoidable. The author also introduces CNNs proposed to mitigate this issue. As CNN-based automated segmentation can take months, researchers need to be aware of the selection of an appropriate CNN, required computer resources, and fundamental limitations. This review serves as a guide for such dense neuronal segmentation.

Deapioplatycodin D inhibits glioblastoma cell proliferation by inducing BNIP3L-mediated incomplete mitophagy

Deapioplatycodin D (DPD) is a triterpenoid saponin natural compound isolated from the Chinese herb Platycodon grandiflorum that has antiviral and antitumor properties. This study aimed to investigate the effects of DPD on glioblastoma (GBM) cells and to determine its intrinsic mechanism of action. Using a CCK8 assay, it was found that DPD significantly inhibited the growth of GBM cells. DPD-treated GBM cells contained swollen and degenerated mitochondria with empty vesicular bilayer membrane-like autophagic vesicle structures in the periphery of the mitochondria under transmission electron microscopy. DPD activated autophagy in GBM cells and induced a blockage of autophagic flux in the late stage. Transcriptomics identified differences in mitophagy-related genes, and analysis of the levels of the corresponding proteins indicated that mitophagy in GBM cells was induced mainly through BNIP3L. Increased expression of BNIP3L disrupts the Bcl-2-Beclin-1 complex, thereby releasing Beclin-1 and activating autophagy. Autophagy was inhibited after silencing of BNIP3L and overexpression of Bcl-2 in GBM cells, and the growth inhibitory effect of DPD was significantly reduced. This result demonstrated that DPD induces mitophagy in GBM cells through BNIP3L. Finally, activation of incomplete mitophagy in GBM cells by DPD through BNIP3L in vivo was demonstrated by establishing a mouse subcutaneous xenograft tumor model. In this study, in vitro and in vivo experiments established that DPD inhibited GBM cell growth by inducing BNIP3L-mediated incomplete mitophagy, which provides an experimental basis for studying new treatments of GBM.Graphical

Morphological and Anatomical Deformities of Hirudo verbana, Carena 1820 (Annelida, Hirudinea) After Feeding: Light and Electron Microscopic Analysis.

Leeches are widely used as model organisms in scientific studies and medical treatments. Medical leeches are hematophagous parasites that usually feed on the blood of their hosts. Some leeches show deformities, usually after feeding. This causes both medical and economic losses as it reduces the effectiveness of leeches in cultivation and medical treatment. The aim of this study was to investigate the effects of morphological deformations after feeding in Hirudo verbana, Carena 1820 (Annelida, Hirudinea), an important species in medical leech treatments. For this purpose, both histopathological and scanning electron microscopy examinations of starved and fed leeches were performed. The causes of deformities in medical leeches were found to be due to overfeeding, which caused cracks on the intestinal surface and therefore deterioration of the tissues. It is also thought that the immunological agents in the fed blood destroyed the medical leech tissue in these regions. In addition, it was determined that the cellular structure of the shaped blood elements stored in the cavity after feeding was preserved for a long time (months) without deterioration. It is certain that revealing the mechanism by which this occurs will inspire the preservation of blood for a long time in blood transfusion.

Incorporation of recombinant proteins into extracellular vesicles by Lactococcus cremoris

Extracellular vesicles (EVs) are nanosized lipid bilayer particles released by various cellular organisms that carry an array of bioactive molecules. EVs have diagnostic potential, as they play a role in intercellular interspecies communication, and could be applied in drug delivery. In contrast to mammalian cell-derived EVs, the study of EVs from bacteria, particularly Gram-positive bacteria, received less research attention. This study aimed to investigate the production of EVs by lactic acid bacterium Lactococcus cremoris NZ9000 and to examine the impact of recombinant protein expression on their formation and protein content. Four different recombinant proteins were expressed in L. cremoris NZ9000, in different forms of expression and combinations, and the produced EVs were isolated using the standard ultracentrifugation method. The presence of vesicular structures (50–200 nm) in the samples was confirmed by transmission electron microscopy and by flow cytometry using membrane-specific stain. Mass spectrometry analyses confirmed the presence of recombinant proteins in the EVs fraction, with amounts ranging from 13.17 to 100%, highlighting their significant incorporation into the vesicles, together with intrinsic L. cremoris NZ9000 proteins that were either more abundant in the cytoplasm (ribosomal proteins, metabolic enzymes) or present in the membrane. The presence of the most abundant lactococcal proteins in EVs fraction suggests that protein cargo-loading of EVs in L. cremoris NZ9000 is not regulated. However, our data suggests that L. cremoris NZ9000 genetically engineered to express recombinant proteins can produce EVs containing these proteins in scalable manner. As L. cremoris NZ9000 is considered safe bacterium, EVs from L. cremoris NZ9000 could have several advantages over EVs from other bacteria, implying possible biotechnological applications, e.g. in therapeutic protein delivery.