Search Results (343)

Background: Once considered a sterile organ, the human stomach is now known to harbor a diverse microbial community that may influence both gastric homeostasis and disease. While extensive research has been conducted worldwide, regional variation in the gastric microbiome remains insufficiently characterized. This study aimed to describe the gastric antrum microbiome of Helicobacter pylori-negative Greek adults using 16S rRNA next-generation sequencing (NGS). Methods: Samples of gastric biopsies were obtained from patients undergoing gastroscopy at a tertiary hospital in Greece. H. pylori infection was excluded through a combination of bacterial culture and patient medical history. The final study group consisted of 9 subjects. Following DNA extraction, the 16S rRNA gene was sequenced on the Ion Torrent™ platform. Bioinformatic processing and statistical analyses were performed using the phyloseq, vegan, and ggplot2 R packages. Microbial composition, relative abundance, and alpha diversity (Shannon and Inverse Simpson indices) were evaluated at the genus level. Results: The gastric microbiome comprised 19 phyla, 150 families, 213 genera, and 391 species. The predominant phyla were Proteobacteria (36.92%), Firmicutes (34.21%), and Bacteroidetes (12.97%). The most prevalent families were Streptococcaceae, Helicobacteraceae, Prevotellaceae, and Pasteurellaceae. At the genus level, Streptococcus (21.71%), Helicobacter (18.39%), and Prevotella (9.99%) accounted for nearly half of the total relative abundance. Alpha diversity indices indicated moderate richness and evenness across samples. Conclusions: The gastric antrum microbiome of H. pylori-negative Greek individuals exhibits substantial taxonomic diversity dominated by Proteobacteria and Firmicutes. The microbial community structure aligns closely with profiles reported in other global populations. These findings provide a reference baseline for future comparative analyses involving H. pylori-positive individuals to better understand microbiome shifts associated with colonization and gastric disease. Full article

Background/Objectives: The gut microbiome plays an important role in the colonization of an individual by Clostridioides difficile and in the development of Clostridioides difficile infection (CDI). The main purpose of this study was to compare the gut microbiomes of patients with CDI and healthy individuals. Methods: We prospectively included 48 individuals: 32 patients with CDI and 16 healthy individuals. Microbiomes were analyzed by sequencing the hypervariable regions of the 16S rRNA gene using an Ion GeneStudio™ S5 System. Further statistical analysis of microbiome data was performed with the open-source programming language R version 3.5.2. Results: Among the CDI patients, Firmicutes and Proteobacteria were the most abundant phyla, while Enterobacteriaceae and Enterococcaceae were the most abundant families. Genus-level analysis showed that Enterococcus was the dominant genus in CDI patients; in contrast, in healthy individuals, Faecalibacterium was the most abundant. The MaAsLin2 tool revealed that members of the family Enterococcaceae and the genus Enterococcus were more abundant in patients with CDI than in healthy individuals. Alpha and beta diversity did not reveal differences between the two study groups. Conclusions: We observed differences in microbiome patterns between healthy individuals and CDI patients that were consistent with the literature. Further studies are needed. Full article

Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) is now the most common liver disease worldwide, with a continuously increasing prevalence. The mechanisms involved in its pathophysiology are numerous and may include metabolic, environmental, and genetic factors. Genome-wide association studies have identified key genetic variants, most notably in PNPLA3, TM6SF2, MBOAT7, GCKR, and HSD17B13. This mini review discusses the mechanisms through which these variants contribute to the disease pathogenesis, an area that remains a rapidly evolving field of research. Beyond improving our understanding of MASLD, the identification of these variants may also aid in the development of targeted pharmacological approaches. We first summarize the major genetic variants associated with MASLD and then present findings from studies exploring how these variants may influence the efficacy of emerging pharmacotherapies. Finally, we examine the therapeutic agents in the field of precision medicine that are currently being tested in clinical trials. These therapeutic opportunities are a promising approach that may provide individualized solutions for this chronic liver disorder that affects a wide range of the population. Full article

Inga edulis Mart. (Fabaceae) is a multipurpose fruit tree widely cultivated in Ecuador. We explored how contrasting cultivation systems are associated with variation in fruit traits and genetic diversity by comparing agroforestry plantations and traditional home gardens. Trees in agroforestry systems exhibited significantly larger pods whereas home-garden populations showed higher levels of genetic diversity. These patterns suggest a potential trade-off between productivity-oriented management and the maintenance of genetic variation, possibly reflecting differences in management practices and seed sourcing. These results highlight the complementary roles of agroforestry and home gardens in the sustainable use and in situ conservation of I. edulis within traditional landscapes. Full article

Alginate is a widely used and versatile biopolymer with an ever-expanding range of applications in the pharmaceutical and biomedical industries. This highlights the importance of developing sustainable and renewable production sources. Conventional extraction methods, although effective, are often energy-intensive and rely on harsh chemicals. In this context, brown algae are a promising alternative due to their abundance and renewability. This study investigated the potential of Saccorhiza polyschides and Sargassum muticum as sources of sodium alginate (SA), thus optimising an extraction process that combines acid treatment with an alkaline step. The extracted biopolymers were characterised using FTIR, H-NMR, STA, SEM/EDX, viscosity measurements, dynamic light scattering, and spectrophotometric assays of residual polyphenols and proteins. The optimised extraction conditions produced yields above 20% of high-purity alginate. When compared with commercial SA, the extracted materials showed comparable quality while relying on a simplified, solvent-reduced protocol that improves process efficiency and reduces the environmental impact. These results demonstrate that S. polyschides and S. muticum are promising, locally available sources of high-quality sodium alginate, and that industrially relevant yields (>20%) can be achieved through an environmentally conscious two-step extraction process. Full article

Background/Objectives: Hypertensive disorders of pregnancy (HDP) remain a major contributor to maternal morbidity and mortality worldwide, yet early-life reproductive factors such as age at menarche have been insufficiently explored in relation to HDP. Therefore, we aimed to evaluate the association between age at menarche and the risk of HDP in a cohort of Mexican pregnant women. Methods: We conducted a retrospective cohort study among 1344 women with singleton pregnancies receiving care at a tertiary hospital in Mexico City in 2024. Age at menarche was categorized as <12, 12–14, and >14 years. HDP diagnoses were extracted from clinical records. Poisson regression with robust variance was used to estimate adjusted risk ratios (RRs). Sensitivity analyses included alternative menarche categorizations and restricted cubic spline models. Counterfactual mediation analyses assessed indirect effects through reconstructed prepregnancy BMI and gestational diabetes. Results: Both early (<12 years) and late (>14 years) menarche were associated with higher HDP risk than the 12–14-year reference (adjusted RR = 1.81; 95% CI 1.42–2.30, and 1.74; 95% CI 1.27–2.38, respectively). Spline models confirmed a U-shaped association. Mediation analyses indicated that prepregnancy BMI did not meaningfully mediate the association for either early or late menarche (<5% mediated). Gestational diabetes explained a modest proportion of the association for early menarche (≈14%), but not for late menarche. Conclusions: Age at menarche showed a robust U-shaped association with HDP, mostly independent of adiposity and gestational diabetes, within the limits of the available measurements. Incorporating pubertal timing into routine reproductive history taking may enhance contextual risk assessment for HDP. Full article

Introduction: Multiple sclerosis (MS) is a chronic autoimmune inflammatory disorder of the central nervous system (CNS) that leads to demyelination of CNS neurons and is influenced by genetic, environmental, and lifestyle factors, including diet and obesity. Methods: This review aims to analyze at the molecular level the relationship between obesity, as a chronic inflammatory condition, and the pathophysiology of MS, as a chronic autoimmune inflammatory disease, in order to understand the complex links between obesity and MS through a search of the PubMed and Google Scholar databases. Discussion: Chronic inflammation and OS are interconnected processes, causing a toxic state, which contributes to the development of CNS neuroinflammation and neuronal damage, resulting in neuronal demyelination and the onset of MS. Adipose tissue is a complex endocrine organ; in addition to being a lipid storage organ, it secretes cytokines and adipokines, which are involved in the regulation of hormones, metabolism, inflammation, and whole-body homeostasis. Obesity triggers chronic low-grade inflammation, disruption of the blood–brain barrier (BBB) and brain metabolism, infiltration of the CNS by immune cells, production of ROS, and generation of oxidative stress (OS). Anti-inflammatory and pro-inflammatory adipokines are also implicated in MS and obesity. Conclusions: Obesity affects MS through common underlying mechanisms and seems to be a modifiable risk factor. Antioxidant and anti-inflammatory compounds with multi-functional characteristics could be additional tools to slow the progression of MS and its promotion through obesity while also offering potential treatment options for both conditions via their multi-targeting characteristics. Full article

Diabetes mellitus (DM) is a complex, heterogeneous, hyperglycemic chronic metabolic disorder. Type 2 diabetes mellitus (T2DM) is characterized by progressive loss of insulin secretion from pancreatic islet β-cells due to IR (insulin resistance), which is a feature of metabolic syndrome (MetS). Chronic hyperglycemia in patients with T2DM in synergy with other metabolic abnormalities causes complications such as diabetic ketoacidosis, osmotic diuresis and hyperglycemic diabetic coma, as well as chronic microvascular and macrovascular complications such as atherosclerotic cardiovascular disease (ASCVD), peripheral artery disease (PAD) and cerebrovascular events, which implicate the formation of reactive species and the promotion of inflammatory pathways. In these events, natural or synthetic antioxidants and minerals seem to have ameliorative effects and may serve as beneficial co-treatment options. In view of these terms, the aim of this study is to investigate the underlying mechanisms of T2DM, its clinical presentation, and its complications. Additionally, the association of the pathogenesis of T2DM and the occurrence of its complications with obesity, chronic inflammation, oxidative stress (OS), insulin resistance (IR), hepatic steatosis, and dyslipidemia is examined, whilst molecular pathways, such as NF-κB and JAK/STAT, are also summarized, under the scope of the effects of several antioxidant compounds and minerals on their progression. The interrelation of T2DM with these conditions, as well as the effects of antioxidant supplementation, seems to be bidirectional, and it is recommended that obese patients be screened for T2DM and adopt lifestyle changes, including exercise, diet modification, and weight loss, in addition to potentially taking multifunctional supplements that offer antioxidant and anti-inflammatory potential. However, many aspects of the protective mechanisms of such antioxidants remain to be elucidated, with more drawbacks in their pharmacokinetic behavior, such as their poor absorption and solubility, waiting to be resolved. Full article

Multidrug resistance (MDR) presents a significant challenge in the treatment of glioblastoma. We evaluated six novel adamantane–sclareol hybrids that integrate a natural labdane diterpene scaffold with an adamantane moiety to address this issue. Compounds 2, 5, and 6 demonstrated the ability to bypass P-glycoprotein (P-gp)-mediated resistance in resistant U87-TxR cells and induced collateral sensitivity, with compound 2 exhibiting the highest selectivity for glioblastoma compared to normal glial cells. Mechanistic studies revealed that compounds 2 and 5 selectively triggered early apoptosis in MDR cells, significantly elevated levels of H₂O₂ and peroxynitrite, and disrupted mitochondrial membrane potential. Additionally, these compounds altered the expression of key genes involved in glutathione (GSH) and thioredoxin (Trx) antioxidant defense systems and increased ASK1 protein levels, indicating the activation of ROS-driven apoptotic signaling. Both compounds inhibited P-gp function, leading to enhanced intracellular accumulation of rhodamine 123 (Rho 123) and synergistically sensitized U87-TxR cells to paclitaxel (PTX). A preliminary Rag1 xenograft study demonstrated that compound 5 effectively suppressed tumor growth without causing significant weight loss. Collectively, these findings position adamantane–sclareol hybrids, particularly compounds 2 and 5, as promising strategies that exploit an MDR-associated reactive oxygen species (ROS) vulnerability, combining selective cytotoxicity, redox disruption, and P-gp modulation to eliminate resistant glioblastoma cells and enhance the efficacy of chemotherapeutics. Full article

Cardiopulmonary resuscitation (CPR) is a vital skill for healthcare professionals, crucial in life-saving situations. More than 80% of cardiac arrest cases occur out of hospital. As the demand for competent CPR practitioners grows, the effectiveness of training methods becomes increasingly important, especially for undergraduate students preparing to enter the healthcare field. The primary objective of our study is to investigate the effectiveness of simulation-based teaching methods and by integrating innovative technologies, such as the OMNI2 simulator, to enhance practitioners’ performance and to improve the precision and objectivity of CPR instruction. A cohort of 144 undergraduate students from the Nursing School Department of the National Kapodistrian University of Athens participated in an 8 h Basic Life Support Seminar. It consisted of a 5 h theoretical instruction followed by 3 h of practical training using the OMNI2 simulator. Each student was tasked to identify cardiac arrest and to perform two cycles of CPR according to the 2021 guidelines. Metrics, including total session time, cycles performed, compression-to-ventilation ratio, compression depth, compressions and ventilations per minute, full recoil, peak inspiratory pressure, and ventilation duration, were measured and compared against the simulator’s preset targets. Statistically significant differences (p < 0.05) were observed for all outcomes. In conclusion, while simulation-based teaching has conventionally been proven effective for CPR proficiency, real-time data collected in this study reveal a disparity between anticipated and actual performance. Our research underscores the necessity of refining instructional methods to enhance skill acquisition, potentially leading to improved patient outcomes in the future. Full article

Propolis is a resinous natural product produced by honeybees from plant exudates and beeswax. Its complex chemical composition varies significantly with geographical origin and seasonal factors. This study aimed to characterize the chemical composition of propolis samples collected from different regions of Latvia using gas chromatography–mass spectrometry (GC-MS). In total, 47 metabolites were identified, with chemical profiles dominated by phenolic acids and their esters—compounds typical of European propolis. Regional variations reflected differences in local vegetation, and two samples exhibited flavonoid constituents indicative of poplar-type botanical sources. The Daugavpils sample, which showed a particularly rich chemical profile, was further fractionated chromatographically, leading to the isolation of twelve metabolites: 2’,4’,6’-trihydroxy-4-methoxy dihydrochalcone, 2’,6’,4-trihydroxy-4’-methoxy dihydrochalcone, 2’,6’-dihydroxy-4,4’-dimethoxy dihydrochalcone, 2’,6’-dihydroxy-4’-methoxy dihydrochalcone, 2’,4’,6’-trihydroxy dihydrochalcone, palmitic acid, benzyl benzoate, cinnamyl cinnamate, pinostrobin, pinostrobin chalcone, pinocembrin, and pinobanksin. Given the limited prior research on Latvian propolis, this study provides valuable insights into its chemical diversity and the influence of regional flora on its composition. Full article

Objectives: We examined how opposing running slopes can modulate interval training effects on aerobic performance and reduction–oxidation (REDOX) determinants. Methods: Fourteen physically active volunteers, assigned to either the Uphill group (UG) or the Downhill group (DG), completed 16 workouts of ten 30-s runs, at either +10% or −10% grade, with a work-to-rest ratio of 1:2 at 90% of their Maximum Aerobic Speed (MAS) over 8 weeks. Maximal oxygen uptake (VO_2max), MAS, Running Economy (RE), time to exhaustion at MAS (Tmax), respiratory exchange ratio (RER), and blood lactate at rest, 5th, and 10th runs were evaluated pre-, mid-, and post-training. Also, REDOX markers [Total Antioxidant Capacity (TAC), Protein Carbonyls (PCs) were assessed in blood samples taken at rest and 3 min post-exercise of the first and last workouts. Results: VO_2max was unchanged in both groups; in the DG, MAS increased (from 14.2 ± 1.7 to 15.0 ± 1.5 km/h, d = 0.43), and post-training RER significantly increased (from 1.06 ± 0.07 to 1.12 ± 0.03). In the last training session, blood lactate levels increased in the UG (from 9.30 ± 2.69 mmοl/L to 13.34 ± 4.64 mmοl/L) but remained low and unchanged in DG (<2 mmοl/L). Post-training, resting TAC decreased in both groups, and the exercise-induced rise in PC levels was attenuated. Conclusions: Despite the brief intervention, VO₂max levels were maintained in both groups, with divergent changes in metabolic, REDOX, and performance indicators; uphill HIIT may serve for enhancing lactate tolerance, while downhill intermittent running may improve running economy. Full article

The aim of the present study was to test the central-periphery hypothesis (CPH) of evolutionary genetics in terms of genetic diversity and differentiation in Alnus glutinosa (L.) Gaertn., 1790 and Picea abies (L.) H. Karst. populations. A total of 18 nuclear SSR loci were used to evaluate genetic diversity and differentiation of two rear-edge populations of each tree species from the south-eastern edges of their distribution ranges in Greece, and two populations of each species from the core distribution area in Lithuania. Peripheral populations of A. glutinosa exhibited high genetic diversity (mean Ar = 7.99, mean He = 0.72) and low genetic differentiation (peripheral and core population F_ST were 0.031 and 0.008, respectively). The genetic diversity values were even higher in the peripheral populations of P. abies (mean Ar = 12.27, mean He = 0.78), while genetic differentiation was also low (peripheral and core population F_ST was 0.013 and 0.011, respectively). Genetic differentiation between the peripheral and core regions was also low (F_ST = 0.038 and G″_ST = 0.262 for A. glutinosa and F_ST = 0.023 and G″_ST = 0.172 for P. abies). Observed heterozygosity was found to be higher in peripheral populations (0.80 on average for alder and 0.84 for spruce) than in core ones (0.72 and 0.83 on average for A. glutinosa and P. abies, respectively). On the other hand, expected heterozygosity was higher in A. glutinosa core populations than in its peripheral ones (0.73 vs. 0.72 on average for core and peripheral alder populations), while spruce populations were less heterozygous in the core area (0.78 vs. 0.75 on average for peripheral and core spruce populations, respectively). These results indicate only partial agreement with CPH. Rear-edge populations showed higher genetic differentiation, while their lower genetic diversity was not significantly different from that of core populations. The investigated rear-edge populations of A. glutinosa and P. abies present valuable genetic reserves of European importance. They show local adaptation and present ample genetic variation, and their effective population size will likely be sufficient for adaptive evolution in the future. Their long-term conservation status should be prioritized. Full article

Background/Objectives: Klebsiella pneumoniae ST258 and ST11 are global high-risk antimicrobial-resistant clones known for their virulence and resistance gene dissemination. This study aims to identify these clones in a Greek tertiary hospital and understand their resistance profiles and transmission dynamics. Methods: In January 2025, we isolated two distinct carbapenem-resistant K. pneumoniae in a Greek tertiary hospital: INT18S from an ICU patient’s bronchioalveolar lavage and INT20U from a urine sample in the emergency unit. Antimicrobial susceptibility testing (via Microscan system) and Whole-Genome Sequencing (WGS) were conducted on both isolates and their genomes were submitted to the NCBI. Results: The INT18S isolate carried the bla_KPC-2 gene and belonged to the ST258 clone. The INT20U isolate carried the bla_NDM-1 gene and belonged to the ST11 clone lineage. Both isolates contained at least one of the extended spectra β-lactamase genes tested (TEM, SHV, OXA-1 and CTX-M group). Conclusions: The co-existence of the high-risk K. pneumoniae clones ST258 and ST11 in different hospital departments increases the risk of resistance gene transfer and suggests potential intra-hospital transmission pathways. Understanding their resistance profiles is critical for guiding treatment strategies and preventing the spread of multidrug-resistant pathogens. Full article

Background: Social media addiction is a growing concern among undergraduates, with nursing students particularly vulnerable as their stressful academic and clinical context may promote excessive use, impaired sleep, and higher depression risk. Therefore, we aimed to evaluate whether sleep disturbance mediates the association between problematic social media use and symptoms of depression among nursing students in Mexico. Methods: We conducted a multicenter, cross-sectional, analytical study using a random sample of 638 nursing students from three Mexican public universities. Between August and December 2024, participants completed validated scales for social media addiction, sleep quality, and depression. Counterfactual causal mediation analysis was performed using logistic regression with robust errors. Results: Sleep disturbance affected 51.7% of students, and 27.5% reported depression. Social media addiction showed a dose–response association with both outcomes. Mediation analysis revealed a total effect on depression (OR = 2.19; 95% CI = 1.45–3.30) and an indirect effect via sleep disturbance (OR = 1.22; 95% CI = 1.01–1.38), explaining 31.4% of the effect. Conclusions: Sleep disturbance partially mediates this association. Interventions addressing digital behavior and sleep hygiene may improve mental health in nursing students. Full article