Transmission Electron Microscopy Examination Research Articles

Improved photocatalytic activity triggered by UV light, as well as electrochemical sensing characteristics of MgO nanoparticles

ABSTRACT The current study’s objective was to investigate the potential applications of synthesised magnesium oxide nanoparticles (MgO NPs) as green fuel through solution combustion with leaves of tulsi (holy basil). The end product was further calcined for 3 h at 800°C to produce a well-crystalline nanomaterial. Transmission electron microscopy (TEM) examinations indicated a typical crystallite size of approximately 52 nm, determined by applying Scherer’s formula. The results from the scanning electron microscope (SEM) revealed a morphology that is clumped, puffy, and porous. The energy band gap (Eg) values for MgO NPs were determined to be 4.31 eV using DRS data, verifying the semiconductor behaviour of the NPs. Degradation experiments were conducted on two dyes, Fast Blue (FB) and Fast Orange (FO), exposed to UV light for 90 minutes. Under UV light, the photocatalytic degradation of FO (80.35%) and FB (80.5%) reached their maximum. A graphite paste electrode was used for cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and sensor investigations. The cyclic CVs of the MgO NPs-modified graphite paste electrode in 0.1 M NaOH were scanned at 10 to 50 mV/s to determine the specific capacitance values of 250.3 Fg−1. Based on the acquired EIS data, the MgO NPs used as the electrode displayed pseudocapacitive capacitor characteristics. Further, the proposed sensor was employed to determine the Pb2+ and Li+ ions in water and showed sensitivity in the order of 0.005 and 0.006 A. Therefore, MgO NPs synthesised via green solution combustion may have excellent applications as photocatalysts and electrochemical sensors.

Is it really descemetocele? Morphology of extremely thin membrane that remained after severe corneal melting: a case report.

The aim of this study was to report transmission electron microscopic findings of a case with whole corneal descemetocele following infective corneal ulcer for the first time in literature. A 72-year-old male patient presented with infective corneal ulcer. After resolution of the infection, corneoscleral transplantation was performed. The excised very thin corneal membrane was processed for transmission electron microscopic examination. Transmission electron microscopic examination of the specimen revealed many layered structures that consisted of two different types of cells. The first type consisted of lighter staining polygonal cells, while the second consisted of elongated cells with relatively dense staining. All cells were connected with a large number of gap or adherens junctions with intercalation of the cell membranes of adjacent cells. A haphazard distribution of cytoplasmic microfilaments were also observed in all of the cell types. There was no evidence of the presence of endothelial cells throughout the specimen. There was also no evidence of Descemet membrane presence except for a small part adjacent to iris tissue that contained some melanosomes. Although we clinically diagnosed descemetocele, Descemet membrane was not present at the electron microscopic level, and thus, the expression "descemetocele" is inappropriate.

Metallic and metallic oxide nanoparticles toxicity primarily targets the mitochondria of hepatocytes and renal cells.

Nanoparticles (NPs) are utilized in various applications, posing potential risks to human health, tissues, cells, and macromolecules. This study aimed to investigate the ultrastructural alterations in hepatocytes and renal tubular cells induced by metallic and metal oxide NPs. Adult healthy male Wistar albino rats (Rattus norvegicus) were divided into 6 (n = 7) control and 6 treated groups (n = 7). The rats in the treated groups exposed daily to silver NPs, gold NPs, zinc oxide NPs, silicon dioxide NPs, copper oxide NPs, and ferric oxide NPs for 35 days. The members of the control group for each corresponding NPs received the respective vehicle. Liver and kidney tissue blocks from all rats were processed for Transmission Electron Microscopy (TEM) examinations. The hepatocytes and renal tubular cells of all NPs-treated rats demonstrated mitochondrial ultrastructural alterations mainly cristolysis, swelling, membrane disruption, lucent matrices, matrices lysis, and electron-dense deposits. However, other organelles demonstrated injury but to a lesser extent in the form of shrunken nuclei, nuclear membrane indentation, endoplasmic reticulum fragmentation, cellular membranes enfolding, brush border microvilli disruption, lysosomal hyperplasia, ribosomes dropping, and peroxisome formation. One may conclude from the findings that the hepatocytes and the renal tubular cells mitochondria are the main targets for nanoparticles toxicity ending in mitochondrial disruption and cell injury. Further studies taking into account the relation of mitochondrial ultrastructural damage with a weakened antioxidant defense system induced by chronic exposure to nanomaterials are needed.

Angelica sinensis polysaccharides ameliorate 5-FU-induced stress anemia via promoting extramedullary erythroblastic island central macrophage-mediated erythroid differentiation

BackgroundChronic anemia, especially chemotherapy-induced anemia, is a common and intractable symptom. Puzzlingly, the conventional anemic treatment may lead to various side effects, and the mechanism of stress anemia remains unclear. MethodsHere, peripheral blood, histopathological and transmission electron microscopical examination, colony forming test, flow cytometry, and qRT-PCR assay were used to investigate the effects of Angelia sinensis polysaccharide (ASP), one main active ingredient of Chinese herb medicine Angelica sinensis, on ameliorating 5-fluorouracil (5-FU)-induced stress anemia. ResultsWe found that intraperitoneal injection to a C57BL/6J mouse ASP 100 mg/kg per day for consecutive 10 days or 14 days, remarkably accelerated the recovery of RBC, hemoglobin, and hematocrit in blood. ASP alleviated 5-FU-caused impairment of bone marrow cell and BFU-E enumeration. Meanwhile, ASP antagonized 5-FU promoting extramedullary erythropoiesis in the spleen, inducing splenomegaly due to stress erythroblastic islands, and occurrence of megakaryocytes and hematopoietic precursors in splenic colonies. ASP increased splenic stress BFU-E enumeration, driving BFU-E differentiation towards Pro-E and end-stage erythroblasts. Furthermore, ASP increased the number of F4/80+VCAM-1+ splenic erythroblastic island central macrophages, upregulating genetic expression of EPOR, Emp, VCAM-1, Hmox-1, Trf, TfR1, Fpn1, Spi-C, DNase2a, Tim4, MertK, and Klf1 in splenocytes. ConclusionsOur findings indicate that the possible mechanism of chemotherapy-induced anemia is related to stress erythroid maturation arrest. Whereas, ASP may promote stress erythroid differentiation via elevated EPO sensitivity in extramedullary hematopoietic organs and enhanced macrophage-mediated adhesion, iron homeostasis and transfer, and nuclear engulfment, which may represent a promising therapeutic strategy.

A Novel Technique for Corneal Transepithelial Electrical Resistance Measurement in Mice.

We developed a technique that can measure corneal transepithelial electrical resistance (TER) in mice, which was used for evaluating corneal toxicity induced by ophthalmic drugs. We used a tissue culture well and its insert to mount the mouse globe and separated the cornea from the rest of the globe to enable corneal TER measurements to be taken. The explanted mouse eyes were divided into groups, and the corneal epithelia were exposed to different concentrations of BAC. Half of these eyes were fixed for transmission electron microscopy (TEM) examination and the other for ZO-1 immunohistochemical (IHC) evaluation. After exposure to control, 0.1%, 0.2%, and 0.5% BAC, the TER was 100 ± 0%, 91 ± 14%, 83 ± 13%, and 34 ± 12% of the pre-exposure TER at 1 min, respectively, with a statistically significant decrease in the 0.5% group. After 3 min, the TER showed a statistically significant decrease in the 0.2% and 0.5% groups. The TEM examinations showed a loss of epithelial tight junctions between superficial cells in the 0.2% and 0.5% groups. The IHC examination showed decreased ZO-1 staining of the corneal epithelium of the same groups as compared to the control. To the best of our knowledge, we succeeded in developing an innovative technique for corneal TER measurement in mice.

A HRTEM-EDS-SAED Study of Precipitates in Mg-Zn-Zr Alloy

In this study, aging heat treatment was performed on extruded Mg-Zn-Zr alloy. Aging was performed on as-extruded samples at 180°C for 1-2-4-8 and 24 hours. Microhardness tests were made to obtain the aging curve. Detailed transmission electron microscopy (TEM) examinations such as selected area electron diffraction (SAED), energy dispersive spectrometry (EDS), and high resolution transmission electron microscopy (HRTEM) were used to investigate the microstructure, second phases, and precipitates. Size, type, and morphologies of second phases and precipitates were studied aided by advanced transmission electron microscopy techniques. With the help of hardness test results peak aged condition was found to be 8 hour aging. TEM examinations were detailed for the 8-hour aged sample. It was observed that the precipitates responsible for age hardening were MgZn2. Moreover, the majority of these precipitates were β’1 phase.

Formation of the crust on the surface of cold-climate aeolian quartz grains – A nano-scale study

Sand-sized quartz grains selected from sediments of a Pleistocene inland dune (eastern Poland) were subjected to a series of laboratory analyses, including grain-size distribution, morphoscopy analysis, microtextural analysis using scanning electron microscope (SEM) and nanostructural analysis using transmission electron microscope (TEM). The results indicate the presence of a crust on the surface of all of the studied quartz grains and a surprisingly low number of aeolian-induced mechanical microtextures. The TEM examination identifies illite-smectite assemblages as the main component of the crust, accompanied by amorphous silica, local accumulation of Fe, K, Ca, Mg oxides, and mineral particles (quartz, K-feldspar, chlorite). The thickness of the crust reaches approx. 0.1–0.2 μm and varies from the minimum on micro-protrusions up to the maximum in micro-cavities. Here, we present a new theory on the origin of the crust observed on the surface of cold-climate aeolian quartz grains. We postulate that the crust is formed within a near-surface saltation layer during active aeolian transport of sand-sized grains and clay-sized particles operating under cold-climate conditions. The development of abrasion features and the formation of the crust are interpreted here to occur simultaneously and continuously during the aeolian transport. The formation of the crust results from specific properties of aeolian transport (i.e. self-induced electrification and electrification mechanisms of quartz grains) and the quartz grains themselves (i.e. grain shape and surface microtopography).

LASIS-Assisted Copper Nanoparticle Synthesis and Characterization, along with UV-Visible Spectroscopy

This study investigates the creation of copper nanoparticles (CuNPs) using chemical reduction and laser ablation in liquid (LASIS). UV-visible spectroscopy is used to examine the optical characteristics of the nanoparticles created by these techniques. The purpose of the study is to compare the stability, efficacy, and particle size of CuNPs produced using different techniques. When comparing the LASIS method to the chemical reduction process, Transmission Electron Microscopy (TEM) examination revealed that the former produced smaller and more uniform nanoparticles. This work demonstrates the effectiveness of both synthesis techniques, with LASIS clearly outperforming the other in the production of superior CuNPs with more control over particle size and dispersion. A thorough explanation of the chemical reduction method and LASIS used in the synthesis of copper nanoparticles is provided, and UV-visible spectroscopy is used to characterize the resulting particles.

Anatomical, Histological and Transmission Electron Microscopic Examination of Liver in Chinese Goose (Anser cygnoides)

Background: The liver, the main organ in the continuity of energy supply, is the largest gland in the body. The liver, which has functions such as cleansing the body from toxins, synthesizing bile, secreting the synthesized bile and regulating metabolism, acts as an endocrine and exocrine gland. The liver is a complex organ that processes the digested and absorbed substances, stores them for the benefit of other organs or transfers them to the circulatory system, thus creating a transition zone between the digestive system and the circulatory system. The aim of this study is to examine the Chinese goose (Anser cygnoides) liver Anatomically, Histologically and by Transmission Electron Microscopy (TEM). Methods: In this study Chinese geese (Anser cygnoides) were procured from a private farm in Aksaray, 6 females and 6 males, were utilized. Result: Tissue samples were examined under a light microscope with Hematoxylin Eosin (HE) staining method. Histologically, it was observed that the liver in Chinese goose (Anser cygnoides) did not have the typical lobule structure, consisted of many lobules and the interlobular septum was thin. Hepatocytes were oval and centrally located and merged to form remark cords and these remark cords were separated by sinusoids. Kupffer cells were present. Lymph nodules were intensely observed in the examined tissues. Bile duct, arteria hepatica and vena porta forming the Kiernan’s space were found. It was determined that each unit with the vena centralis was similar to the lobule structure. Healthy mitochondrial structures and heterochromatic-appearing hepatocytes and Kupffer cells were observed electron microscopically. The nucleus of the hepatocyte was round and euchromatic, the nuclear membrane was healthy and intact and the nucleolus was centrally located. The cytoplasm contained a very small number of small vacuoles. It was observed that the cytoplasm was homogeneously distributed. Mitochondria were normal in appearance, with regular double membranes and healthy cristae. A very prominent bile duct and a healthy endoplasmic reticulum structure were observed.

Microstructure and mechanical behavior in a spherical L12 nanoprecipitates strengthened Ni35Co27.5Cr27.5Al5Ti5 high-entropy alloy fabricated by direct casting and heat treatment

Intricate thermomechanical processing (TMP) including casting, homogenization, cold rolling, annealing and aging, has been widely used to achieve L12-strengthened CoCrNi-based medium- and high-entropy alloys (MEAs/HEAs). However, a large number of parts are usually manufactured by direct casting. We fabricated a non-equiatomic Ni35Co27.5Cr27.5Al5Ti5 HEA consisting of spherical L12 nanoprecipitates and FCC matrix using casting, homogenization and aging. Notably, both the homogenized and aged Ni35Co27.5Cr27.5Al5Ti5 HEA samples exhibit equiaxed grains, with the latter showcasing uniformly distributed spherical L12 nanoprecipitates in the FCC matrix. The average size and volume fraction of these nanoprecipitates in the aged HEA are ∼10.9 nm and ∼41.9 vol%, respectively. Mechanical testing reveals remarkable improvements in the aged HEA, with a yield strength of ∼916 MPa, an ultimate tensile strength of ∼1220 MPa, and a total elongation of ∼21.5 %. The observed enhancement is primarily attributed to precipitation strengthening mechanism. Digital image correlation (DIC) analysis of tensile deformation demonstrates uniform strain distribution in both the homogenized and aged HEA samples. In addition, electron channeling contrast imaging (ECCI) and transmission electron microscopy (TEM) examinations unveil a complex interplay of deformation mechanisms, including multiple planar slip, dislocation shearing coherent L12 precipitates, superpartials, stacking fault (SF) networks, and Lomer-Cottrell (L-C) locks. These mechanisms collectively impede dislocation motion, thereby contributing to the excellent strain-hardening ability and outstanding strength-ductility synergy of the HEA.

Histochemical and ultrastructural evaluation of myopic corneal lenticules based on refractive error.

This study aimed to investigate cell degeneration, apoptosis, and ultrastructural differences in refractive lenticules (RL) obtained using small incision lenticule extraction (SMILE) compared with spherical equivalence (SE) refraction values. This study included 84 eyes from 42 patients. Patients were divided into two groups according to the SE values: those with values below 4 diopters (D) (Group 1) and above 4 diopters (D) (Group 2). Patients who did not belong to the same SE group were excluded from the study. One RL obtained from each patient was separated for light microscopy and immunohistochemical examinations, and another for transmission electron microscopy (TEM) examinations. Caspase-3 for apoptosis and alpha-smooth muscle actin (α-SMA) for cell degeneration were evaluated using immunohistochemical examinations. Histological analyses showed that the density of collagen fibres was greater in Group 1 than in Group 2. Glycoaminoglycan and glycoprotein staining intensities were also higher in Group 1. TEM observations showed that Group 1 had intact cell and nuclear membranes, peripheral heterochromatin, and large nuclei, while Group 2 showed heterochromatin condensation and fragmentation, increased intracellular vacuoles, and loss of cytoplasm. Immunohistochemical analyses revealed that α-SMA and caspase-3 were significantly higher in Group 2 than in Group 1 (p < 0.001 and p < 0.001, respectively). Cell degeneration and apoptosis were significantly more common in the RLs with high SE values after SMILE surgery. The tissue response induced by surgery was more severe in the RLs with high SE values. This should be considered when reusing RLs.

Characterization of Salmonella phage of the genus Kayfunavirus isolated from sewage infecting clinical strains of Salmonella enterica.

The emergence of multi-drug resistance in Salmonella, causing food-borne infections, is a significant issue. With over 2,600 serovars in in Salmonella sp., it is crucial to identify specific solutions for each serovar. Phage therapy serves as an alternate treatment option. In this study, vB_SalP_792 phage was obtained from sewage, forming plaques in eight out of 13 tested clinical S. enterica isolates. Transmission electron microscopy (TEM) examination revealed a T7-like morphotype. The phage was characterized by its stability, life cycle, antibiofilm, and lytic ability in food sources. The phage remains stable throughout a range of temperatures (-20 to 70°C), pH levels (3-11), and in chloroform and ether. It also exhibited lytic activity within a range of MOIs from 0.0001 to 100. The life cycle revealed that 95% of the phages attached to their host within 3 min, followed by a 5-min latent period, resulting in a 50 PFU/cell burst size. The vB_SalP_792 phage genome has a dsDNA with a length of 37,281 bp and a GC content of 51%. There are 42 coding sequences (CDS), with 24 having putative functions and no resistance or virulence-related genes. The vB_SalP_792 phage significantly reduced the bacterial load in the established biofilms and also in egg whites. Thus, vB_SalP_792 phage can serve as an effective biocontrol agent for preventing Salmonella infections in food, and its potent lytic activity against the clinical isolates of S. enterica, sets out vB_SalP_792 phage as a successful candidate for future in vivo studies and therapeutical application against drug-resistant Salmonella infections.

Syzygium aromaticum-mediated green synthesis of iron oxide nanoparticles for efficient heavy metal removal from aqueous solutions

The current study focused on the environmentally friendly synthesis of iron oxide nanoparticles (IONPs) using ferric nitrate Fe(NO3)3 9H2O as a precursor and aqueous Syzygium aromaticum (clove) extract as a reducing agent. Several analytical methods, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and ultraviolet–visible (UV–Vis.) spectroscopy, were used to confirm the synthesized iron oxide nanoparticles. These procedures were carried out to learn more about the surface shape and chemical composition of the produced iron oxide nanoparticles. The mean size of iron nanoparticles was determined by TEM examination to be 4.7 nm. The characterization revealed that the primary component of iron nanoparticles was magnetite when the Syzygium aromaticum extract was utilized as a reducing agent for Fe3+. For application, synthesized material was used to remove the harmful Cr (VI) ions from an aqueous solution. The batch adsorption approach was utilized to maximize the effects of significant elements such as pH, adsorbent dose, treatment duration, and initial Cr (VI) ions concentration to achieve the highest removal of Cr (VI) ions. The experimental adsorption data were fitted using various isotherm and kinetic adsorption models.

Tailoring perovskite ceramics for improved structure, vibrational behaviors and radiation protection: The role of lanthanum in PbTiO3

This study investigates the characteristics of lanthanum (La)-doped lead titanate (PbLaxTi(1-3x/4)O3 where, x = 0.0, 0.02, 0.04, 0.06, 0.08, and 0.1), a type of perovskite ceramic. It specifically focuses on analyzing its structure, vibrational properties, and efficacy in shielding against radiation. The prepared samples are investigated by X-ray diffraction (XRD), which clarified that the small doping of La (x ≤ 0.06) produced the required phase, and increasing the La doping (x > 0.06) produced nonrequired phases (secondary phase). Also, increasing the La doping converted the crystal symmetry from tetragonal to cubic, which was confirmed by the tetragonality raio (c/a) calculations. Also, the samples are investigated by Fourier transform infrared (FTIR) spectroscopy to confirm the XRD results. Transmission electron microscopy (TEM) examination clarified that the prepared samples were in the nanoscale range with a maximum crystallite size value of around 70 nm. In addition, the shielding effectiveness of all the prepared samples was theoretically evaluated using the Phy-X/PDS program by considering characteristics such as the linear attenuation coefficient (GLAC), mean free path (GMFP), transmission factor (TF), and radiation protection efficiency (RPE). Increasing the La concentration increases the theoretical density to 4.98 gm/cm3 at x = 0.1, leading to low TF and GMFP values and high GLAC values. This produces samples with high attenuation to radiation and high shielding effectiveness.

Temperature‐Induced Structural Evolution and Magnetism in Self‐Intercalated V1+xSe2 Nanoplates

Abstract2D van der Waals (vdW) magnets provide the ideal platform for studying magnetism at low dimensions, where the magnetic properties can be further tuned by intercalating magnetic species and manipulating their stoichiometry and local atomic configuration. However, achieving stoichiometric intercalated 2D magnets necessitates precise control of growth parameters to avoid local compositional variations, which fosters phase coexistence that significantly impacts magnetic properties. Here a comprehensive scanning transmission electron microscopy (STEM) examination of the structural evolution in chemical vapor deposition (CVD)‐grown self‐intercalated V1+xSe2 nanoplates is shown, exploring their response to annealing temperature variations and the subsequent influence on magnetic properties. By combining ex situ and in situ post‐growth annealing, the rearrangement of intercalants is directly observed at the interlayer and identify a structural phase transition of the nanodomains embedded in the VSe2 matrix from V3Se4 to a V5Se8 structure occurring at ≈250 °C. The interlayer reconstruction is manifested by a positive‐to‐negative cross‐over in the magnetoresistance and an upturn in resistivity at low temperatures. The results provide new ways for tailoring 2D vdW magnets through post‐growth thermal annealing.

Regulatory role of Prunus mume DAM6 on lipid body accumulation and phytohormone metabolism in the dormant vegetative meristem.

Bud dormancy is a crucial process in the annual growth cycle of woody perennials. In Rosaceae fruit tree species, DORMANCY-ASSOCIATED MADS-box (DAM) transcription factor genes regulating bud dormancy have been identified, but their molecular roles in meristematic tissues have not been thoroughly characterized. In this study, molecular and physiological analyses of transgenic apple plants overexpressing the Japanese apricot DAM6 gene (PmDAM6) and Japanese apricot cultivars and F1 individuals with contrasting dormancy characteristics revealed the metabolic pathways controlled by PmDAM6. Our transcriptome analysis and transmission electron microscopy examination demonstrated that PmDAM6 promotes the accumulation of lipid bodies and inhibits cell division in the dormant vegetative meristem by down-regulating the expression of lipid catabolism genes (GDSL ESTERASE/LIPASE and OIL BODY LIPASE) and CYCLIN genes, respectively. Our findings also indicate PmDAM6 promotes abscisic acid (ABA) accumulation and decreases cytokinin (CTK) accumulation in vegetative buds by up-regulating the expression of the ABA biosynthesis gene ARABIDOPSIS ALDEHYDE OXIDASE and the CTK catabolism gene CYTOKININ DEHYDROGENASE, while also down-regulating the expression of the CTK biosynthesis genes ISOPENTENYL TRANSFERASE (IPT) and CYP735A. Additionally, PmDAM6 modulates gibberellin (GA) metabolism by up-regulating GA2-OXIDASE expression and down-regulating GA3-OXIDASE expression. Furthermore, PmDAM6 may also indirectly promote lipid accumulation and restrict cell division by limiting the accumulation of CTK and GA in buds. In conclusion, using our valuable genetic platform, we clarified how PmDAM6 modifies diverse cellular processes, including lipid catabolism, phytohormone (ABA, CTK, and GA) biosynthesis and catabolism, and cell division, in the dormant vegetative meristem.

Transmission Electron Microscopy and Dynamic Light Scattering-Fundamental Perspective

Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS) are fundamental tools in nanotechnology and materials science, providing information about the structural and dynamic properties of nanomaterials and colloidal systems. This review provides a thorough examination of TEM and DLS, beginning with a discussion of their fundamental principles. It discusses the interaction of electron beams in TEM and the dynamics of scattered light in DLS, followed by an examination of instrumentation and experimental setups, including recent advances for increased resolution and sensitivity. The article then discusses the numerous applications of TEM and DLS in nanomaterial characterization. It includes analyses of nanoparticle size, shape, morphology, and distribution, as well as research into colloidal system dynamics such as nanoparticle aggregation, diffusion, and stability. The review concludes with a forward-looking perspective on emerging trends and future directions in nanomaterial characterization. It emphasizes the potential of TEM and DLS to overcome current challenges and advance our understanding of nanoscale phenomena. Overall, this comprehensive review provides researchers and practitioners with a solid understanding of the TEM and DLS principles, methodologies, and applications, as well as valuable fundamental insights.

Characterization and therapeutic potential of chitosan‐zinc oxide nanostructured particles synthesized using crab shell derived biopolymer

AbstractThe development of novel drug candidates for treating microbial infections and cancer turns into a challenging task. The biopolymer‐based nanomaterials have gained popularity for their effective roles in the pharmaceutical sector. The present investigation aims to valorize crab shell wastes to extract chitosan. The obtained (chitosan) biomass was utilized to synthesize chitosan‐zinc oxide nanoparticles (Ch‐ZnO‐NPs). The nanomaterial characterization was achieved by a variety of physicochemical techniques including UV, Fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), elemental analysis, and High‐resolution transmission electron microscopic (HR‐TEM) examination. The synthesized nanomaterials have a particle size range of 35–80 nm and are more stable with a zeta potential value of (−40.78) mv. Additionally, the designed nanomaterials were utilized to evaluate the biological efficiency. The minimal inhibitory concentration value of Ch‐ZnO‐NPs was observed as 10 μg/mL. The designed nanomaterials significantly reduced the growth of Vibrio alginolyticus and Bacillus cereus and inhibited biofilm formation. The synthesized Ch‐ZnO‐NPs unveiled cytotoxic effects on A549 cells with an IC50 (half‐maximal inhibitory concentration) of 20 μg/mL. Furthermore, substantial increase in cell death was noticed in A549 cells treated with Ch‐ZnO‐NPs. Consequently, this investigation concludes that Ch‐ZnO‐NPs may act as a biomedicine.

Modulation of autophagy affected tumorigenesis induced by the envelope glycoprotein of JSRV

Ovine pulmonary adenocarcinoma (OPA), caused by the jaagsiekte sheep retrovirus (JSRV), is a chronic, progressive, and contagious lung tumor that seriously affects sheep production. It also represents a valuable animal model for several human lung adenocarcinomas. However, little is known about the role of autophagy in OPA tumorigenesis. Here, Western blotting combined with transmission electron microscopy examination and Cyto-ID dye staining was employed for evaluation of changes of autophagic levels. The results of the present study showed that expression of the autophagy marker proteins Beclin-1 and LC3 was decreased in OPA lung tissues, as well as in cells overexpressing the envelope glycoprotein of JSRV (JSRV Env). Reduced numbers of autophagosomes were also observed in cells overexpressing JSRV Env, although assessment of autophagic flux showed that JSRV Env overexpression did not block the formation of autophagosomes, suggesting increased degradation of autolysosomes. Last, mouse xenograft experiments indicated that inhibition of autophagy by 3-methyladenine suppressed both tumor growth and the epithelial-to-mesenchymal transition. In conclusion, JSRV, through JSRV Env, takes advantage of the autophagy process, leading to the development of OPA.

Intraocular pressure across the lifespan of Tg-MYOCY437H mice

Transgenic C57BL/6 mice expressing human myocilinY437 (Tg-MYOCY437H) are a well-established model for primary open-angle glaucoma (POAG). While the reduced trabecular meshwork (TM) cellularity due to severe endoplasmic reticulum (ER) stress has been characterized as the etiology of this model, there is a limited understanding of how glaucomatous phenotypes evolve over the lifespan of Tg-MyocY437H mice. In this study, we compiled the model's intraocular pressure (IOP) data recorded in our laboratory from 2017 to 2023 and selected representative eyes to measure the outflow facility (Cr), a critical parameter indicating the condition of the conventional TM pathway. We found that Tg-MYOCY437H mice aged 4−12 months exhibited significantly higher IOPs than age-matched C57BL/6 mice. Notably, a decline in IOP was observed in Tg-MYOCY437H mice at 17−24 months of age, a phenomenon not attributable to the gene dosage of mutant myocilin. Measurements of the Cr of Tg-MYOCY437H mice indicated that the age-related IOP reduction was not a result of ongoing TM damage. Instead, Hematoxylin and Eosin staining, immunohistochemistry analysis, and transmission electron microscopic examination revealed that this reduction might be induced by degenerations of the non-pigmented epithelium in the ciliary body of aged Tg-MYOCY437H mice. Overall, our findings provide a comprehensive profile of mutant myocilin-induced ocular changes over the Tg-MYOCY437H mouse lifespan and suggest a specific temporal window of elevated IOP that may be ideal for experimental purposes.