Search Results (12,551)

Mitochondria are the energy factories of a cell and mitochondrial morphology, quantity, membrane potential, and DNA copy number can change depending on metabolic requirements and/or genetic defects. Different mutations in mitochondrial DNA might affect mitochondrial morphology and membrane potential differently. In this study we investigated mitochondrial morphology and membrane potential in vitro in mesoangioblast-derived human myotubes harboring a pathogenic mtDNA mutation and analyzed mitochondrial behavior following fusion with healthy mesoangioblasts. Myotubes were differentiated in vitro from mesoangioblasts obtained from two mitochondrial myopathy patients, M02 (96% m.3271T>C) and M11 (73% m.3291T>C), and from a functionally healthy male control, M06 (3% m.3243A>G). On day 5 of differentiation, healthy male mesoangioblasts (mM06) were added to mutant myotube cultures to allow cell fusion. On day 11, mitochondrial morphology and membrane potential were assessed by three-dimensional live-cell imaging using spinning disk confocal microscopy with tetramethylrhodamine methyl ester (TMRM). Following live imaging, cells were fixed and subjected to Y-chromosome fluorescence in situ hybridization (FISH), enabling identification and retrospective analysis of hybrid (i.e., fused with male control mesoangioblasts) and non-hybrid (i.e., not fused with these control mesoangioblasts) myotubes within the same imaging fields. Quantitative image analysis at the level of individual myotubes revealed that, when normalized to sarcoplasmic volume, mitochondrial volume, object number, and membrane potential did not differ between mutant and control myotubes despite heteroplasmy levels exceeding 70%. Fusion of healthy mM06 mesoangioblasts did not impair myotube formation and resulted in redistribution of mitochondrial content without an increase in mitochondrial object number, consistent with integration of donor mitochondria into the existing mitochondrial network. Across conditions, mitochondrial parameters were strongly influenced by myotube size, underscoring the importance of accounting for biological variation when quantifying mitochondrial features. Together, these findings demonstrate that high mtDNA mutation loads do not necessarily alter mitochondrial morphology or membrane potential under standard in vitro differentiation conditions and provide mechanistic insight into mitochondrial behavior following mesoangioblast fusion in human myotubes. Fusion of healthy mesoangioblasts supports integration of donor mitochondria into the existing network without compromising myogenesis, consistent with mitochondrial mixing rather than replacement. Full article

To address the challenges of zwitterionic dissociation and steric hindrance in the esterification of α-aromatic amino acids, this study prepared the solid superacid catalyst SO₄²⁻/TiO₂/HZSM-5 (STH) and its plasma-modified derivative SO₄²⁻/TiO₂/HZSM-5 (STH-RF) via an aging-impregnation method. Systematic characterization revealed that plasma modification optimizes the crystal morphology and particle dispersion of the catalyst, while also achieving pore clearance and an increase in the specific surface area. Furthermore, it gradationally enhances acidic properties by increasing the abundance of strong acid and Lewis acid sites, and promotes uniform loading and stable bonding of the SO₄²⁻ active component. Performance evaluation using the synthesis of L-phenylalanine methyl ester as a model reaction demonstrated that STH-RF exhibits optimal catalytic activity, affording a product yield of 85.7%, which is significantly higher than that of unmodified STH (19%) and the homogeneous catalyst H₂SO₄ (63%). This superior performance originates from a “structure–acidity” synergistic effect, combining the thermodynamic advantage of a lower energy barrier for the rate-determining step (12.6 Kcal·mol⁻¹) with efficient kinetics under optimal process conditions (1.0 MPa, 2000 rpm, 170 °C). Moreover, STH-RF maintained a yield above 80% after four consecutive reaction cycles, indicating excellent stability. This work provides a novel catalytic system for the green and efficient synthesis of highly hindered α-amino acid derivatives, holding significant theoretical and practical implications. Full article

Electro slag remelting steel is a technology of tertiary metallurgy that can be used in the production of special structural steels where high purity is required to influence the quality of the final products. This work deals with the evolution of steel purity comparing vacuum degassing (VD) and electro slag remelting (ESR) technologies in terms of the chemical composition of non-metallic inclusions and their morphology. The present work primarily studies the creep behavior of special structural steel at two different initial material states (VD and ESR steel) tested in the range from 450 to 650 °C. A rather unique plastometric experimental methodology of accelerated creep testing, which consists of a slow plastic deformation of a material under long-term stress at an elevated temperature, was used to study the behavior of the prepared specimens. The results show that, after remelting the steel, there was an increase in micropurity due to a reduction in the average size and, in particular, a reduction in the maximum size of non-metallic inclusions. The results of creep behavior show a particular difference at 600 °C, where ESR steel shows higher relaxation phase stress values as well as higher creep strength factor values compared with VD steel. Full article

Anatomical variations of the caudal ventral lamina of the sixth cervical vertebra (C6), referred to as equine caudal cervical morphologic variations (ECCMV), and radiographic modelling of the caudal cervical articular process joints (APJ) are commonly identified in sport horses, yet their interrelationship and relevance for athletic performance remain controversial. This retrospective observational study aimed to determine the prevalence of ECCMV and APJ modelling in a clinically sound warmblood sport horse population, to evaluate a potential association and to assess if ECCMV affects competition performances. Records of 200 warmbloods, presented for pre-purchase examination between 2020 and 2024 were reviewed: the predominant breed was Hanoverian (n = 131), followed by Oldenburg (n = 27) and Holsteiner (n = 22), including 127 geldings, 61 mares and 12 stallions with a median age of 5. ECCMV was diagnosed on latero-lateral radiographs if the caudal ventral lamina of C6 was uni- or bilaterally absent, and APJ modelling at C6/C7 was graded as either normal or mild or moderate to severe. Competition placings and lifetime earnings of each horse were collected from the German National Equestrian Federation database. ECCMV was found in 30% of horses and APJ modelling in 32.5% (mild 26.5%, moderate/severe 6%). There was no significant association between the presence of ECCMV, APJ alterations and competition results, but horses with ECCMV were less likely to exhibit radiographic changes in the adjacent APJ compared to those with a normal C6 morphology (23.3% vs. 36.4%). In conclusion, ECCMV is a common anatomical variation in clinically sound warmbloods, neither predisposing them to APJ modelling nor limiting athletic performance. Full article

Taurine is a free amino acid with various effects, such as developing the nervous system, an immune function, an antioxidative effect, enhancing muscle and cardiovascular function, and reducing fatigue. In this study, we investigated the effect of taurine supplementation on ischemic neuronal damage in the hippocampus of gerbils. Taurine (150 mg/kg) was orally administered to gerbils before and after induction of transient ischemia. Histologically, we examined surviving and degenerating neurons by neuronal nuclei immunostaining and fluoro-jade C (FJC) staining. Gliosis was morphologically confirmed by GFAP and Iba1 immunostaining. Compared to the ischemia and pre-treated gerbils, pre- and post-taurine supplementation was neuroprotective by maintaining higher number of mature NeuN-immunoreactive neurons and reducing neuronal death (FJC-stained cells) in the hippocampal CA1 region. Additionally, the ischemia-induced reactive astrocytosis and microgliosis was significantly mitigated by long-term taurine treatment in the gerbil hippocampus. Furthermore, we confirmed that pre- and post-taurine supplementation downregulated ischemia-mediated induction in the MAPK cascade, such as ERK, JNK, and p38, which are involved in oxidative stress, inflammation, apoptosis, and cell differentiation, and this treatment upregulated an ischemia-mediated reduction in antioxidants such as SOD2, GPX4, and anti-apoptotic factor Bcl-2 in the gerbil hippocampus. Pre- and post-taurine supplementation also downregulated again the ischemic injury-mediated activation of transcriptional factor NFkβ, an important gene expression regulator, especially in the inflammatory response, and pro-apoptotic factor Bax in the gerbil hippocampus. Our present results suggest that pre- and post-taurine supplementation has potential in neuroprotection against ischemia-induced neuronal death and glial activation by attenuating oxidative stress and apoptosis. Full article

The extraction of hydrogen sulfide (H₂S) from gases is essential in numerous industrial applications to safeguard human safety, preserve equipment, and mitigate environmental harm. In these circumstances, zeolites are crucial for the extraction of H₂S from these gases. This study reports, for the first time, the synthesis of 13X zeolite from Angren kaolin using an optimized, fully autoclave-free fusion/hydrothermal route. This method enables 13X crystallization under atmospheric pressure, greatly improving process safety, cost-efficiency, and scalability. The impact of the NaOH ratio on kaolin synthesis was investigated. Thereafter, these samples were analyzed utilizing XRD, SEM, EDS, and BET techniques to evaluate their crystalline structures, surface morphologies, and textural properties. The adsorption of H₂S from natural gas was performed using both synthetic and commercial samples in a custom-designed laboratory-scale adsorption machine. The results demonstrated that the synthesized zeolite designated as 13X-III, with a high NaOH ratio, displayed an adsorption capacity higher than that of commercially available 13X molecular sieves (C13X). The synthesized 13X efficiently removed H₂S from various gases containing H₂S, such as biogas, refinery gases, and natural gas. Full article

Kaolin is an abundant, low-cost filler for elastomeric compounds. The kaolin used here is primarily kaolinite, chemically clean, and contains a fine particle population. Although agglomeration is evident, it can be mitigated by appropriate physical processing and, when desired, by chemical coupling. This study evaluates kaolin in natural rubber (NR) and examines how adding bis(triethoxysilylpropyl) tetrasulfide (TESPT) during mixing affects filler–matrix compatibility, viscoelastic response, cure stability, and mechanical performance. Kaolin was structurally and morphologically characterized, and the compounds were prepared in a closed mixer coupled to a torque rheometer under controlled dispersion conditions. Part 1 assessed NR with kaolin without a coupling agent, and Part 2 assessed the NR–kaolin with TESPT added during mixing (0.5 and 5 phr). Small-amplitude oscillatory shear (SAOS) was used to probe viscoelastic behavior, while oscillating disk rheometry (ODR) and tensile tests quantified cure and mechanical properties. In Part 1, kaolin increased NR stiffness in SAOS and raised the 100% and 300% moduli by about 40% and 50%, respectively, relative to the unfilled NR compound, while reducing cure reversion from 30% to 10% at 150 °C. In Part 2, TESPT produced a threshold-like response: 0.5 phr caused only minor changes, whereas 5 phr led to pronounced stiffening and cure stabilization. At 5 phr, a low-frequency plateau in G′ below 0.1 Hz with no G′–G″ crossover was observed, accompanied by higher M_H and ΔM in ODR and reversion suppressed to 1% after 30 min. These trends indicate the formation of a more connected filler-rubber network, promoted by TESPT-assisted interfacial coupling/adhesion, while also reflecting the ability of TESPT (tetrasulfide) to contribute sulfur and modify the curing chemistry. Mechanically, kaolin produced marked stiffness increases, with the 100% and 300% moduli increasing by an additional 9% and 36%, respectively, at 5 phr TESPT. At the same time, ultimate tensile strength remained lower than that of neat NR, and elongation at break decreased slightly. Overall, adding TESPT during mixing enhances interfacial coupling and network connectivity and, at higher loading, also influences cure chemistry, yielding higher modulus and strongly improved reversion resistance without increasing ultimate tensile strength relative to neat NR. Full article

This study describes the clinical and genetic features of Meesmann epithelial corneal dystrophy (MECD) in two unrelated families and reports new genotype–phenotype associations. Ten patients from a Lebanese family (n = 4) (Family 1) and a Spanish family (n = 6) (Family 2) underwent ophthalmologic evaluation, in vivo confocal microscopy (IVCM), anterior segment optical coherence tomography (AS-OCT) with epithelial thickness mapping (ET-map), and targeted next-generation sequencing (NGS) using a custom-designed 133-gene panel associated with anterior segment dystrophies. In Family 1, a novel homozygous KRT12 c.1181T>C (p.Leu394Pro) variant was identified in the symptomatic proband and his clinically asymptomatic brother, while both parents, who were first cousins, were heterozygous for this nucleotide variant. The proband also carried the heterozygous KRT3 c.250C>T (p.Arg84Trp) variant, which has been previously reported but, to our knowledge, has not been described in co-occurrence until now. In addition, the proband showed a complex phenotype with signs of MECD and epithelial basal membrane alterations consistent with epithelial basement membrane dystrophy (EBMD). In Family 2, four affected members carried the KRT3 c.1492G>A (p.Glu498Lys) variant in heterozygosity, which has been previously described. The elderly members affected showed typical signs of MECD and EBMD. To our knowledge, these concomitant alterations have not been previously described with genetical confirmation. In conclusion, this study provides the first evidence that the co-occurrence of variants in two Meesmann corneal dystrophy-associated genes (KRT3 and KRT12) can jointly account for the disease phenotype. We also highlight the association of MECD with EBMD in both families. Characterization using IVCM and AS-OCT ET-Map provides a deeper understanding of the morphological changes and phenotypic variability in MECD, confirming the utility of this multimodal imaging approach for diagnosis and management. Full article

Black currants (Ribes nigrum L.) and their hybrid berries are distinguished by their exceptionally high content levels of anthocyanin and vitamin C, major phytochemicals with health-promoting properties. This study was designed to substantially reduce the HPLC runtime required for black currant anthocyanin analysis and clarify how key determinants, including morphological traits (berry size and peel proportion), genetic variation across 12 cultivars, and cryogenic milling, affect anthocyanin accumulation and quantification. A rapid HPLC protocol was developed that achieves the high-resolution separation of four major and eight minor anthocyanins in black currant within a 10 min run, enabling efficient, high-throughput analysis, very important in long-term breeding programs due to the large number of genotypes. Cryogenic grinding substantially enhanced the extraction yield and reproducibility relative to just blending. Using the improved extraction and analysis method, a set of anthocyanin content-related morphologic berry traits was systematically evaluated, providing information directly relevant to future phenotyping and breeding efforts. Smaller black currant berries generally have higher total anthocyanin content than larger berries, and these morphological attributes are tightly linked to the genotype. Although a higher peel proportion was related to higher anthocyanin content within genotype, there was no global trend, and anthocyanin contents were similar in different size berry peels. Full article

The physiological relevance of in vitro models is limited because conventional two-dimensional cell culture systems are unable to replicate the structural and functional complexity of native tissues. Extracellular matrix (ECM)-mimetic hydrogels have become important platforms for tissue engineering applications. This work developed hybrid hydrogels that mimic important biochemical and mechanical characteristics of cardiac tissue by combining decellularized bovine pericardium-derived (dBP) ECM, gellan gum (GG), and spermine (SPM). Although dBP offers tissue-specific biological cues, processing compromises its mechanical integrity. This limitation was overcome by adding GG, whose ionic gelation properties were optimized using DMEM and SPM. The hydrogels’ mechanical, biological, physicochemical, and structural characteristics were all evaluated. Under physiologically simulated conditions, the formulations showed quick gelation and long-term stability; scanning electron microscopy revealed an interconnected, ECM-like porous microarchitecture. While uniaxial compression testing provided Young’s modulus values comparable to native myocardium, rheological analysis revealed a concentration-dependent increase in storage modulus with increasing SPM content. H9C2 cardiomyoblasts were used in cytocompatibility studies to confirm that cell viability, morphology, and cytoskeletal organization were all preserved. All of these findings support the potential application of dBP−GG−SPM hydrogels in advanced in vitro cardiac models by showing that they successfully replicate important characteristics of cardiac ECM. Full article

Interfacial reactions between Sn-based solders and Au/Pd/Ni metallization were investigated at 260 °C, with particular emphasis on the effects of Pd and Sn thicknesses. Au/Pd/Ni substrates with Pd layers of approximately 70 nm, 200 nm, and 1 µm were reacted with Sn layers of about 50, 20, and 10 µm. Additionally, Sn-Pd and Sn-3Ag-Pd solders containing 0.1–1 wt.% Pd were reacted with Ni substrates. In the Sn/Au/Pd/Ni reactions, rapid dissolution of the Pd layer and partial Ni dissolution at the early stage promoted the formation of large amounts of faceted (Pd,Ni)Sn₄. With increasing reaction time, continuous Ni diffusion enriched the interfacial region, leading to the nucleation and growth of Ni₃Sn₄. Once the Ni solubility limit in (Pd,Ni)Sn₄ was exceeded, this phase gradually transformed into the thermodynamically more stable Ni₃Sn₄. In addition to phase evolution, Pd was found to significantly influence the interfacial grain morphology. Minor Pd additions enhanced the Ni₃Sn₄ nucleation, resulting in refined and columnar grains. In the Sn-Pd/Ni reactions, low Pd contents led to the rapid replacement of (Pd,Ni)Sn₄ by Ni₃Sn₄, whereas higher Pd contents significantly enhanced the stability and interfacial retention of (Pd,Ni)Sn₄. These results reveal that increasing Pd thickness or Pd content in the solder significantly enhances the stability of (Pd,Ni)Sn₄, whereas reducing Sn thickness markedly accelerates interfacial reactions and phase transformation. The experimental observations can be consistently interpreted using a local interfacial equilibrium hypothesis based on the Sn-Pd-Ni phase diagram. Full article

Clonorchis sinensis and Metagonimus spp. are prevalent parasites in Korea, and accurate diagnosis is essential because treatment dosages differ between infections. However, their eggs are morphologically similar under light microscopy, making differentiation difficult and dependent on examiner expertise. To address this limitation, we evaluated an artificial intelligence (AI)-based automated microscope solution for the simultaneous detection and discrimination of both parasites. Microscopic images from 170 stool samples were analyzed using an AI system based on You Only Look Once version 5. The annotated dataset comprised 9455 egg images (6494 C. sinensis and 2961 Metagonimus spp.), randomly divided at the slide/patient level into training (6862), validation (1301), and test (1292) sets. Diagnostic performance was evaluated using mean average precision, confusion matrix analysis, and correlation with conventional microscopy. The model achieved a classification accuracy of up to 97.8%. C. sinensis showed higher recall and F1 scores, whereas Metagonimus spp. showed higher precision and specificity. Species identification showed complete concordance with conventional microscopy, and egg quantification was strongly correlated. These results indicate that the proposed AI system may serve as a supportive diagnostic tool comparable to conventional microscopy. Full article

This study aimed to explore the effect of doubled CO₂ concentration (d[CO₂]) on the modulation of root morphological structure, leaf potassium (K)/sodium (Na) ratio, and nutrient stoichiometry, as well as water use efficiency (WUE) of a C₄ maize (Zea mays L.) in response to soil drought and salinity. C₄ maize was grown in two atmospheric CO₂ concentrations of 400 and 800 ppm (a[CO₂] and d[CO₂]), subjected to two soil water regimes (well-watered and drought stress) and two soil salinity levels (0 and 100 mM NaCl pot⁻¹ (non-salt and salt stress)). The results indicated that soil drought increased maize root tissue density and specific root length. Both d[CO₂] and salt stress reduced leaf phosphorus (P) and K concentrations; conversely, drought stress enhanced leaf nitrogen (N) and K concentrations. The lower specific leaf area, but greater specific leaf N and N/K under soil drought, was amplified by salt stress. In contrast, d[CO₂] promoted leaf carbon (C)/N and C/K. Notably, d[CO₂] combined with soil drought enhanced leaf K/Na under salt stress. Moreover, d[CO₂] ameliorated the adverse impacts of soil drought and salinity on root morphology in terms of enlarged root length and root surface area, contributing to superior leaf C, N, and K use efficiency and consequently improved C₄ maize plant dry mass and WUE. These findings would provide essential knowledge to elevate salt tolerance and achieve optimal nutrient homeostasis and WUE in C₄ maize, adapting to future drier and more saline soils under a CO₂-enriched scenario. Full article

Soil salinization and alkalinization critically constrain alfalfa (Medicago sativa L.) productivity, yet the regulatory mechanisms underlying its responses to salt–alkali stress are not fully understood. In this study, the alfalfa variety “Zhongmu No. 1” was used as experimental material. The seeds were subjected to salt stress (75 mM NaCl), alkali stress (15 mM NaHCO₃), and combined salt–alkali stress (50 mM NaCl + 5 mM NaHCO₃) in dishes, with ddH₂O serving as the control (CK). After 7 days of germination, the seedlings were transferred to a hydroponic system containing Hoagland nutrient solution supplemented with the corresponding treatments. Following 32 days of stress exposure, leaf and root tissue samples were collected for morphological and physiological measurements, as well as mRNA and miRNA sequencing analyses. Physiological assays revealed significant growth inhibition and increased electrolyte leakage under stress conditions. Transcriptome profiling identified over 5000 common differentially expressed genes (DEGs) in both leaves and roots under stress conditions, mainly enriched in pathways related to “iron ion binding”, “flavonoid biosynthesis”, “MAPK signaling”, and “alpha-Linolenic acid metabolism”. MiRNA sequencing detected 453 miRNAs, including 188 novel candidates, with several differentially expressed miRNAs (DEMs) exhibiting tissue- and stress-specific patterns. Integrated analysis revealed 147, 81, and 140 negatively correlated miRNA–mRNA pairs across three treatment groups, highlighting key regulatory modules in hormone signaling and metabolic pathways. Notably, in the ethylene and abscisic acid signaling pathways, ERF (XLOC_006645) and PP2C (MsG0180000476.01) were found to be regulated by miR5255 and miR172c, respectively, suggesting a post-transcriptional layer of hormonal control. DEM target genes enrichment pathway analyses also identified stress-specific regulation of “Fatty acid degradation”, “Galactose metabolism”, and “Fructose and mannose metabolism”. qRT-PCR validation confirmed the expression trends of selected DEGs and DEMs. Collectively, these findings reveal the complexity of miRNA–mRNA regulatory networks in alfalfa’s response to salt–alkali stress and provide candidate regulators for breeding stress-resilient cultivars. Full article

The green sunfish, Lepomis cyanellus, is a common centrarchid that has been previously reported to harbor several myxosporeans. In May 2022, six L. cyanellus were collected from the Caddo River, Montgomery County, Arkansas, USA, and had their gills, gall bladders, urinary bladders, fins, integument, other major organs, and musculature examined for myxosporeans. A single individual was found to harbor a new species of Myxobolus infecting the soft dorsal fin. A qualitative and quantitative morphological description was based on fresh plasmodia and myxospores. Elliptoid to obovoid myxospores of Myxobolus picassoi sp. n. are asymmetrical, 12.2 µm long × 9.1 µm wide, with two broadly pyriform to broadly ovoid subequal polar capsules. Molecular data consisted of a 2042 base pair sequence of the partial small subunit rRNA gene (SSU). Phylogenetic analysis revealed that M. picassoi sp. n. is a member of a clade of myxosporean species that predominately infect centrarchid sunfishes from North America. This is the fifth report of a Myxobolus from L. cyanellus, but the first report of a species infecting the soft dorsal fin. This article was registered in the Official Register of Zoological Nomenclature (ZooBank) as urn:lsid:zoobank.org:pub:146D21D1-E416-41C7-A1F6-8AB2AC6D9260. Full article