Search Results (8,616)

Degenerative disc disease (DDD) is a major cause of chronic low back pain (LBP), yet the molecular mechanisms driving disc degeneration and pain remain poorly understood. This study analyzed intervertebral disc (IVD) tissue from 36 young patients (median age = 36.00 [31.00, 42.50] years) with herniated discs and LBP, alongside healthy controls, to investigate changes in the extracellular matrix (ECM) and neurochemical alterations. Disc degeneration was assessed using MRI (Pfirrmann grading) and histology (Sive’s criteria). Histochemical and immunohistochemical methods were used to evaluate aggrecan content, calcification, and the expression of nerve growth factor (NGF), substance P (SP), and S-100 protein. MRI findings included Pfirrmann grades V (30.55%), IV (61.11%), III (5.56%), and II (2.78%). Severe histological degeneration (10–12 points) was observed in three patients. Aggrecan depletion correlated with longer pain duration (r = 0.449, p = 0.031). NGF expression was significantly elevated in degenerated discs (p = 0.0287) and strongly correlated with SP (r = 0.785, p = 5.268 × 10⁻⁹). Free nerve endings were identified in 5 cases. ECM calcification, present in 36.1% of patients, was significantly associated with radiculopathy (r = 0.664, p = 0.005). The observed co-localization of NGF and SP suggests a synergistic role in pain development. These results indicate that in young individuals, aggrecan loss, neurochemical imbalance, and ECM calcification are key contributors to DDD and chronic LBP. Full article

Gaming has evolved into a cultural phenomenon with a global reach, captivating millions of individuals. Nevertheless, little is known about this population. We aim to physiologically characterise the Portuguese gamers, bearing in mind that phase angle (PhA) is a general indicator of health, to check possible correlations between body composition, strength, and nutrition. A sample of 35 male gamers (individuals who play video games) was evaluated for anthropometry; body composition through DXA for whole-body bone mineral content (BMC), fat-free mass (FFM, kg), fat mass, and visceral adipose tissue, and through BIA (bioelectrical impedance analysis) for total body water (TBW), water pools (extracellular water and intracellular water, ICW), and PhA; strength through maximal isometric handgrip strength using a dynamometer; and nutritional intake using a three-day food record. Results show that participants are within reference metrics for all the analysed variables except regarding protein and carbohydrate intake (all values are above and below the Acceptable Macronutrient Distribution Ranges, respectively). A positive correlation was observed between PhA and TBW, ICW, handgrip strength, BMC and FFM, and a negative correlation with fat mass (absolute, percentage and visceral). In conclusion, PhA correlates with body composition variables, which aligns with previous research as a predictor of health and performance. Full article

Alcalase was immobilized–stabilized on carrageenan beads following a previously described protocol. Then, the activities of free and immobilized enzymes were compared using different protein substrates (casein, (CS), bovine serum albumin (BSA), or hemoglobin (HG)) at different pH values and temperatures. The observed activity depended on the substrate protein and enzyme formulation used. The highest enzyme activity could be observed at pHs 5, 7, or 10, depending on the substrate protein and the Alcalase formulation. The effect of the temperature at these pHs on the activity versus the different substrate proteins showed a common pattern. At low temperatures, the immobilized enzyme presented higher (mainly at acidic-neutral pH values and using BSA) or similar specific activity than the free enzyme. At temperatures near the optimal for the free enzyme, it became the most active, while at higher temperatures, the immobilized enzyme recovered the lead, although differences in the optimal temperature were not very significant. This may be explained by the lower mobility of the immobilized–stabilized enzyme. The immobilized enzyme could be much more active than the free enzyme or slightly less active, even using mild conditions, depending on the substrate protein, pH, and temperature used to determine the enzyme activity. Full article

Bone integrity is maintained through continuous remodeling, orchestrated by the coordinated actions of osteocytes, osteoblasts, and osteoclasts. Once considered passive bystanders, osteocytes are now recognized as central regulators of this process, mediating biochemical signaling and mechanotransduction. Malfunctioning osteocytes contribute to serious skeletal disorders such as osteoporosis. Mesenchymal stromal cells (MSCs), multipotent stem cells capable of differentiating into osteoblasts, have emerged as promising agents for bone regeneration, primarily through the paracrine effects of their secreted exosomes. MSC-derived exosomes are nanoscale vesicles enriched with proteins, lipids, and nucleic acids that promote intercellular communication, osteoblast proliferation and differentiation, and angiogenesis. Notably, they deliver osteoinductive microRNAs (miRNAs) that influence osteogenic markers and support bone tissue repair. In vivo investigations validate their capacity to enhance bone regeneration, increase bone volume, and improve biomechanical strength. Additionally, MSC-derived exosomes regulate the immune response, creating pro-osteogenic and pro-angiogenic factors, boosting their therapeutic efficacy. Due to their cell-free characteristics, MSC-derived exosomes offer benefits such as diminished immunogenicity and minimal risk of off-target effects. These properties position them as promising and innovative approaches for bone regeneration, integrating immunomodulatory effects with tissue-specific regenerative capabilities. Full article

Flavonoids constitute a broad class of naturally occurring chemical compounds classified as polyphenols, widely present in various plants, fruits, and vegetables. They share a common flavone backbone, composed of two aromatic rings (A and B) connected by a three-carbon bridge forming a heterocyclic ring (C). One representative flavonoid is chrysin, a compound found in honey, propolis, and passionflower (Passiflora spp.). Chrysin exhibits a range of biological activities, including antioxidant, anti-inflammatory, anticancer, neuroprotective, and anxiolytic effects. Its biological activity is primarily attributed to the presence of hydroxyl groups, which facilitate the neutralization of free radicals and the modulation of intracellular signaling pathways. Cellular uptake of chrysin and other flavonoids occurs mainly through passive diffusion; however, certain forms may be transported via specific membrane-associated carrier proteins. Despite its therapeutic potential, chrysin’s bioavailability is significantly limited due to poor aqueous solubility and rapid metabolism in the gastrointestinal tract and liver, which reduces its systemic efficacy. Ongoing research aims to enhance chrysin’s bioavailability through the development of delivery systems such as lipid-based carriers and nanoparticles. Full article

Transcription factors play crucial roles in regulating gene expression, and any dysregulation in their levels could be involved in cancer progression. The role of androgen receptors (AR) and zinc finger (ZNF) proteins in tumors, like prostate cancer (PC), remains poorly understood. Moreover, due to the multifaceted transcriptional behavior of ARs and ZNFs, their biological role in cancer progression may also depend on the interplay with micro-RNAs (miRNAs). Based on The Cancer Genome Atlas (TCGA) database, we analyzed the expression levels of zinc finger transcripts and ARs in PC. Specifically, exploring their involvement in cancer progression and regulation by miRNAs. The analysis relied on several tools to create a multivariate combination of the original biomarkers to improve their diagnostic efficacy. Multidimensional Scaling (MDS) identified two new dimensions that were entered into a regression analysis to determine the best predictors of overall survival (OS) and disease-free interval (DFI). A combination of both dimensions predicted almost 50% (R² = 0.46) of the original variance of OS. Kaplan–Meier survival analysis also confirmed the significance of these two dimensions regarding the clinical output. This study showed preliminary evidence that several transcription factor expression levels belonging to the zinc family and related miRNAs can effectively predict patients’ overall PC survivability. Full article

Honey is a natural product of honeybees that has been consumed for centuries due to its nutritional value and potential health benefits. Recent scientific research has focused on its antioxidant capacity, which is linked to a variety of bioactive compounds such as phenolic acids, enzymes (e.g., glucose oxidase, catalase), flavonoids, ascorbic acid, carotenoids, amino acids, and proteins. Together, these components work synergistically to neutralize free radicals, regulate antioxidant enzyme activity, and reduce oxidative stress. This review decisively outlines the antioxidant effects of honey and presents compelling clinical and experimental evidence supporting its critical role in preventing diseases associated with oxidative stress. Honey stands out for its extensive health benefits, which include robust protection against cardiovascular issues, notable anticancer and anti-inflammatory effects, enhanced glycemic control in diabetes, immune modulation, neuroprotection, and effective wound healing. As a recognized functional food and dietary supplement, honey is essential for the prevention and adjunct treatment of chronic diseases. However, it faces challenges due to variations in composition linked to climatic conditions, geographical and floral sources, as well as hive management practices. The limited number of large-scale clinical trials further underscores the need for more research. Future studies must focus on elucidating honey’s antioxidant mechanisms, standardizing its bioactive compounds, and examining its synergistic effects with other natural antioxidants to fully harness its potential. Full article

The aim of the present observational study was to evaluate the early effect of free-form essential amino acid (EAA) supplementation on cardiac and muscular performance in elderly patients with chronic heart failure (HF) with reduced ejection fraction (HFrEF) and sarcopenia, as add-on to the optimized medical therapy (OMT) for HF. The present study included 60 elderly Caucasian patients suffering from HFrEF and sarcopenia. At the baseline and at follow-up, all patients underwent complete physical examination with the determination of the main anthropometric and hemodynamic parameters. After 6 months of supplementation with EAAs, we observed significant improvements in the parameters of sarcopenia. In addition, there was a significant improvement in glycol-metabolic parameters, and in inflammatory index as high sensitivity C-reactive protein (hs-CRP). In accordance with these results, significant decreases were observed in circulating levels of oxidative stress biomarkers Nox-2 (p < 0.001) and 8-Isoprostane (p < 0.001), and platelet aggregation biomarkers such as sP-Selectin (p < 0.001) and Gp-VI (p < 0.001). Of particular interest, after 6 months’ follow-up, there was a significant improvement in LVEF and global longitudinal strain (GLS). In conclusion, this study demonstrates that targeted nutritional intervention with EEAAs represents a viable therapeutic strategy for addressing the complex interplay between cardiac dysfunction and skeletal muscle wasting in elderly HF patients. Full article

Flammulina filiformis, one of the most delicious and commercially important mushrooms, demonstrates remarkable adaptability to diverse agricultural wastes. However, it is unclear how different substrates affect the degradation of lignocellulosic biomass and the production of lignocellulolytic enzymes in F. filiformis. In this study, label-free comparative proteomic analysis of F. filiformis cultivated on sugarcane bagasse, cotton seed shells, corn cobs, and glucose substrates was conducted to identify degradation mechanism across various substrates. Label-free quantitative proteomics identified 1104 proteins. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis of protein expression differences were predominantly enriched in energy metabolism and carbohydrate metabolic pathways. Detailed characterization of carbohydrate-active enzymes among the identified proteins revealed glucanase (GH7, A0A067NSK0) as the key enzyme. F. filiformis secreted higher levels of cellulases and hemicellulases on sugarcane bagasse substrate. In the cotton seed shells substrate, multiple cellulases functioned collaboratively, while in the corn cobs substrate, glucanase predominated among the cellulases. These findings reveal the enzymatic strategies and metabolic flexibility of F. filiformis in lignocellulose utilization, providing novel insights for metabolic engineering applications in biotechnology. The study establishes a theoretical foundation for optimizing biomass conversion and developing innovative substrates using targeted enzyme systems. Full article

Background: The influence of hospitalization owing to pneumonia on changes in body composition has not been specifically reported. We conducted a prospective cohort study of patients with community-acquired pneumonia (CAP) requiring hospitalization to test the hypothesis that hospitalization affects body composition. Methods: Sixty-four consecutive patients with CAP were recruited. Body composition was measured within 24 h of admission and 24 h before discharge using bioelectrical impedance analysis. The association between changes in body composition and variables obtained at admission was investigated. Index values were calculated as weight divided by height squared. Results: The mean age of the patients was 76.0 ± 8.7 years (78.1% males). The median length of hospitalization was 12.0 days. Weight, body mass index (BMI), skeletal muscle (SM), SM index, fat-free mass (FFM), and FFM index significantly decreased (p < 0.001 for each), but fat mass (FM) and FM index did not. The serum total protein level was the only independent predictor of the lowest quartile of change in SM index (<−0.4) after adjusting for age and sex (p = 0.004). Conclusions: In summary, weight and BMI significantly decreased during hospitalization in patients with CAP, which was attributed to SM reduction. Patients with low serum total protein levels on admission were at risk of an accelerated decrease in the SM index. Nutritional intervention and rehabilitation are important for these patients. Full article

Background: Antibacterial resistance (ABR) poses a major challenge to global health, with methicillin-resistant Staphylococcus aureus (MRSA) being one of the prominent multidrug-resistant strains. MRSA has developed resistance through the expression of Penicillin-Binding Protein 2a (PBP2a), a key transpeptidase enzyme involved in bacterial cell wall biosynthesis. Objectives: The objective was to design and characterize a novel small-molecule inhibitor targeting PBP2a as a strategy to combat MRSA. Methods: We synthesized a new indole triazole conjugate (ITC) using eco-friendly and click chemistry approaches. In vitro antibacterial tests were performed against a panel of strains to evaluate the ITC antibacterial potential. Further, a series of in silico evaluations like molecular docking, MD simulations, free energy landscape (FEL), and principal component analysis (PCA) using the crystal structure of PBP2a (PDB ID: 4CJN), in order to predict the mechanism of action, binding mode, structural stability, and energetic profile of the 4CJN-ITC complex. Results: The compound ITC exhibited noteworthy antibacterial activity, which effectively inhibited the selected strains. Binding score and energy calculations demonstrated high affinity of ITC for the allosteric site of PBP2a and significant interactions responsible for complex stability during MD simulations. Further, FEL and PCA provided insights into the conformational behavior of ITC. These results gave the structural clues for the inhibitory action of ITC on the PBP2a. Conclusions: The integrated in vitro and in silico studies corroborate the potential of ITC as a promising developmental lead targeting PBP2a in MRSA. This study demonstrates the potential usage of rational drug design approaches in addressing therapeutic needs related to ABR. Full article

The objectives of this study were to prepare whey protein–quercetin–gellan gum conjugates using the pH-shift method and to evaluate the impacts of varying pH values and quercetin concentrations on the interaction mechanisms and functional characteristics of the complexes. Spectroscopic analyses (fluorescence, UV-vis, and FT-IR) revealed that new complexes formed under alkaline conditions. Notably, an increasing quercetin concentration led to a reduction in complex particle size and an increase in the zeta potential value, with these effects being more pronounced under alkaline conditions. The particle size was 425.7 nm, and the zeta potential value was −30.00 mV at a quercetin addition concentration of 15 umol/g protein. Additionally, the complexes formed under alkaline conditions exhibited superior foaming capacity, emulsification properties, and significantly enhanced free radical scavenging activity. The complex’s DPPH and ABTS radical scavenging rates rose by 41.57% and 57.69%, respectively. This study provides theoretical foundations and practical insights for developing protein—polyphenol systems, offering significant implications for the application of quercetin functional foods and supplements in the food science and pharmaceutical industries. Full article

Cell-free biosensors harness the selectivity of cellular machinery without living cells’ constraints, offering advantages in environmental monitoring, medical diagnostics, and biotechnological applications. This review examines recent advances in cell-free biosensor development, highlighting their ability to detect diverse analytes including heavy metals, organic pollutants, pathogens, and clinical biomarkers with high sensitivity and specificity. We analyze technological innovations in cell-free protein synthesis optimization, preservation strategies, and field deployment methods that have enhanced sensitivity, and practical applicability. The integration of synthetic biology approaches has enabled complex signal processing, multiplexed detection, and novel sensor designs including riboswitches, split reporter systems, and metabolic sensing modules. Emerging materials such as supported lipid bilayers, hydrogels, and artificial cells are expanding biosensor capabilities through microcompartmentalization and electronic integration. Despite significant progress, challenges remain in standardization, sample interference mitigation, and cost reduction. Future opportunities include smartphone integration, enhanced preservation methods, and hybrid sensing platforms. Cell-free biosensors hold particular promise for point-of-care diagnostics in resource-limited settings, environmental monitoring applications, and food safety testing, representing essential tools for addressing global challenges in healthcare, environmental protection, and biosecurity. Full article

Community detection in complex networks plays a pivotal role in modern scientific research, including in social network analysis and protein structure analysis. Traditional community detection methods face challenges in integrating heterogeneous multi-source information, capturing global semantic relationships, and adapting to dynamic network evolution. This paper proposes a novel unsupervised multimodal community detection algorithm (UMM) based on fractal iteration. The core idea is to design a dual-channel encoder that comprehensively considers node semantic features and network topological structures. Initially, node representation vectors are derived from structural information (using feature vectors when available, or singular value decomposition to obtain feature vectors for nodes without attributes). Subsequently, a parameter-free graph convolutional encoder (PFGC) is developed based on fractal iteration principles to extract high-order semantic representations from structural encodings without requiring any training process. Furthermore, a semantic–structural dual-channel encoder (DC-SSE) is designed, which integrates semantic encodings—reduced in dimensionality via UMAP—with structural features extracted by PFGC to obtain the final node embeddings. These embeddings are then clustered using the K-means algorithm to achieve community partitioning. Experimental results demonstrate that the UMM outperforms existing methods on multiple real-world network datasets. Full article

Over the past decade, the number and diversity of identified protein post-translational modifications (PTMs) have grown significantly. However, most PTMs occur at relatively low abundance, making selective enrichment of modified peptides essential. To address this, we developed a thermodynamic model describing the free beads enrichment in suspension enrichment process and derived a theoretical relationship between material dosage and analyte recovery. The model predicts a non-linear trend, with enrichment efficiency increasing up to an optimal dosage and declining thereafter—a pattern confirmed by experimental data. We validated the model using centrifugation-based enrichment for glycosylated peptides and magnetic-based enrichment for phosphorylated peptides. In both cases, the results aligned with theoretical predictions. Additionally, the optimal dosage varied among peptides with the same modification type, highlighting the importance of tailoring enrichment strategies. This study provides a solid theoretical and experimental basis for optimizing PTMs enrichment and advancing more sensitive, accurate, and efficient mass spectrometry-based proteomic workflows. Full article