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PubMed2026

Quantifying the combined effects of semi-closed terrain and monsoon on PM2.5 and O3 pollution aggregation in the North China Plain.

The North China Plain (NCP) and its surrounding regions represent one of the key priority areas for air pollution control. As anthropogenic emissions decline significantly, the effect of terrain and meteorology on air pollution pattern has become increasingly prominent, particularly given the NCP's unique semi-closed terrain and East Asian monsoon dynamics. However, quantitative characterization of terrain-dominated blocking effects remains unexplored. Here we quantitatively assess the blocking effects of mountains and terrain-coupled meteorological factors on air pollutant dispersion. We find the NCP on the eastern side of the Taihang Mountains showed high PM2.5 and O3 pollution levels, with winter PM2.5 and summer O3 high-value zones showing opposite north-south aggregation patterns. PM2.5 and O3 concentrations were highest in plains, followed by platforms, hills, and finally mountains. Within the 120-km buffer zones of the typical mountains in the NCP and its surrounding regions, PM2.5 and O3 concentrations increased initially with altitude but then decreased markedly above a threshold altitude. Above the threshold altitude, mountain blocking effects became dominant. The effective blocking altitudes of typical mountains in the NCP and its surrounding regions ranged between 22 and 929 m for winter PM2.5 pollution, and between 19 and 1060 m for summer O3 pollution. The Terrain-Wind Close Index indicates that the terrain-coupled East Asian monsoon showed stronger blocking effects on PM2.5 dispersion in southern NCP during winter and on O3 diffusion in northern NCP during summer, matching observed high-pollution zones. This study offers key insights for regional joint air pollution mitigation strategies, as well as regional pollution assessment.

Particulate Matter↗

PubMed2026

Herbicolin A, an antifungal lipopeptide produced by Pantoea agglomerans APC 4211 is a promising biocontrol agent against food spoilage fungi.

Fungal contamination of food with yeast and molds is associated with major economic losses due to spoilage and also poses health risks in the form of mycotoxin production. The strain Pantoea agglomerans APC 4211 isolated from leaves of Ilex aquifolium (holly tree) has broad spectrum antifungal activity against a variety of food spoilage fungi. Genomic analysis of the strain confirmed the presence of biosynthetic gene clusters potentially encoding for the enzymatic machinery required for the production of the antifungal lipopeptide herbicolin A. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) analysis of the cell-free supernatant (CFS) confirmed the presence of molecular masses corresponding to herbicolin A (1300.8 Da), and herbicolin B (1138 Da). Purified herbicolin A has desirable properties for biotechnological applications, including potent antifungal activity against a range of spoilage fungi, thermal stability and resistance to proteases. The lipopeptide has low cytotoxicity against epithelial cell lines and has minimum inhibitory concentrations (MICs) lower than those of some commercial antifungal drugs (0.2-2.5 mg/L). In a model dairy system (10% skim milk), herbicolin A demonstrated excellent solubility and stability, effectively eliminating Aspergillus niger and Penicillium notatum at a concentration of 5 mg/L. Overall, the study determines herbicolin's A spectrum against food spoilage organisms and examines potential applications in food. In conclusion, herbicolin A is a potent, naturally occurring antifungal agent with the potential to be applied as a biopreservative in food systems, providing a safe, clean-label, and efficient compound for synthetic preservatives replacement.

Pantoea↗

PubMed2026

Contemporary surgical decision-making for hallux valgus and hallux rigidus in Switzerland: A national cross-sectional survey using standardized clinical scenarios.

BACKGROUND: Surgical management of hallux valgus and hallux rigidus is influenced by deformity severity, surgeon training, and evolving techniques. Previous surveys in Australia (2012), Switzerland (2015), and Israel (2023) using identical hypothetical cases demonstrated marked regional differences and a recent rise in minimally invasive Chevron-Akin (MICA). Whether these advances have altered contemporary Swiss practice remains unclear. METHODS: An electronic survey replicating the original questionnaire was distributed to members of the Swiss Foot and Ankle Society. Three standardized clinical cases were presented: mild hallux valgus, severe hallux valgus, and hallux valgus et rigidus. Respondents selected nonoperative versus operative management and specified procedures and fixation methods. Demographics, subspecialty training, and surgical volume were recorded. Current results were compared with prior Swiss data to assess temporal change. RESULTS: Eighty surgeons completed the survey (94% foot and ankle specialists). For mild hallux valgus, 87.7% recommended surgery; Scarf osteotomy remained most common (49.4%), followed by Chevron (21.0%) and Minimally Invasive Hallux Valgus correction (14.8%). Minimally Invasive adopters were predominantly mid-career (83% aged 41-50), high-volume surgeons. For severe hallux valgus, 95.1% favoured surgery; MTPJ arthrodesis was preferred (50.6% isolated; 11.1% with Lapidus), while Minimally Invasive Hallux Valgus correction was rarely chosen (2.5%). In hallux valgus et rigidus, 96% selected MTPJ fusion, most commonly plate-and-screw fixation (45.1%). Compared with 2015, fixation strategies evolved, yet procedure selection remained largely unchanged. CONCLUSION: Despite global expansion of minimally invasive bunion surgery, Swiss surgeons continue to favour established open techniques, particularly Scarf osteotomy and fusion-based strategies. Adoption of MIS remains limited and concentrated among high-volume, mid-career specialists, indicating a cautious national diffusion pattern. LEVEL OF EVIDENCE: IV, survey study.

Hallux Valgus↗

PubMed2026

Introgression shapes the genomic conflict landscape of Malus, providing evidence for a reticulate backbone in a woody crop lineage.

Phylogenomic discordance is widespread across plants, but its evolutionary significance is often obscured when conflict is treated primarily as analytical noise rather than as evidence of underlying processes. In woody lineages in particular, incomplete lineage sorting, introgression, and genome duplication can interact over long timescales to produce complex genomic histories that are not adequately summarized by a strictly bifurcating tree. Here, we use Malus as a model woody genus to investigate how these processes structure conflict across a genus-scale, accession-based phylogenomic framework. Using broad taxon sampling, hundreds of nuclear loci, plastid genomes, and genome-wide SNP summaries, we reconstruct a robust nuclear backbone for sampled Malus lineages and evaluate where discordance is concentrated and which processes best explain it. Nuclear analyses resolve eight major clades, whereas conflict is non-random and localized to recurrent hotspots rather than evenly distributed across the tree. Cytonuclear discordance is similarly concentrated, especially around Clade H, represented by sampled accessions of M. tschonoskii, where localized plastid-nuclear disagreement is consistent with candidate plastid capture or organellar introgression. Multiple complementary analyses further indicate that the strongest conflict is not explained by ILS alone, but instead reflects lineage-structured introgression, while polyploid complexes represent additional localized sources of evolutionary complexity. Together, these results provide evidence for a reticulate genomic backbone in Malus and show how integrating nuclear, plastid, and genome-wide conflict analyses can help distinguish background discordance from process-specific signals in woody plant radiations. Several lineage-level reticulation hypotheses identified here should now be tested with broader population-level sampling and curated reference accessions.

Malus↗

PubMed2026

Muscle mechanical and architectural adaptations in response to different endurance training modalities in older adults.

INTRODUCTION: This study examined the effects of various cycling endurance training modalities, matched for total workload, on muscle mechanical and architectural characteristics in older adults. METHODS: Fifty healthy participants (25 females, 59-79 yrs) were randomly assigned to five age and sex matched groups: one control and four workload-matched training groups (moderate-intensity continuous, heavy-intensity continuous, high-intensity interval, and heavy-intensity continuous in eccentric cycling). Training consisted of three weekly sessions over 8 weeks, with evaluations conducted at the beginning and end of the intervention with maximal voluntary isometric contractions at five different knee angles (90, 75, 60, 45, 30°) and maximal concentric and eccentric isokinetic contractions at five different knee angular velocities (45, 90, 150, 210, 250°/s). Maximum voluntary isometric torque (Tmax) and optimal knee angle (KAopt) were obtained from the isometric contractions; eccentric torque (Tecc) and maximum concentric knee angular velocity (Vmax) were obtained from the isokinetic contractions. The muscle architecture of vastus lateralis (VL) at rest (muscle thickness, pennation angle, and fascicle length) was investigated as well. RESULTS: No statistical differences were detected between groups or time points in VL architecture, in KAopt and in Vmax. A main effect of time was observed for Tmax (p < 0.001, η2p = 0.458) and Tecc (p = 0.002, η2p = 0.191) in all the investigated training groups. The within-group comparisons indicate significant increases in Tmax in the training groups, but not in the control group. CONCLUSIONS: Commonly applied endurance exercises improve muscle mechanical capacity (Tmax and Tecc) in older adults, with no structural (architectural) muscle remodelling, when matched for workload.

Humans↗

PubMed2026

Magnesium administration for vasospasm prevention in acute aneurysmal SAH: a multicenter randomized controlled trial.

Aneurysmal subarachnoid hemorrhage (aSAH) is associated with significant morbidity and mortality, with cerebral vasospasm (CV) and delayed cerebral ischemia (DCI) being the primary contributors to poor outcomes. Magnesium sulfate (MgSO₄) has demonstrated neuroprotective and vasodilatory properties in preclinical models. This study aimed to evaluate the effect of targeted serum magnesium (Mg) maintenance on CV and exploratory clinical outcomes following aSAH. We conducted a prospective, multicenter, single-blind RCT across four neurocritical care units in Korea between 2019 and 2024. A total of 121 aSAH patients were randomized to receive either IV MgSO₄or placebo within six hours of admission. Mg was infused to maintain serum concentrations between 2.0 and 3.0 mg/dL for 14 days. The primary outcome was incidence of CV assessed by transcranial doppler. Secondary outcomes included DCI, ICU and hospital length of stay, modified rankin scale (mRS) at 30 days. There was no significant difference in overall CV incidence; however, the Mg group demonstrated significantly lower mean flow velocity and Lindegaard ratio on days 4-9, indicating reduced vasospasm severity. In exploratory multivariable analyses, a median serum Mg concentration > 2.5 mg/dL during the first 14 hospital days was independently associated with lower risks of CV and DCI. No significant differences were found in mRS scores, ICU and hospital stay, or serious adverse events between groups. Early targeted Mg administration improved TCD-derived hemodynamic markers during the peak vasospasm window; however, it did not significantly reduce CV incidence, DCI, ICU or hospital stay, or 30-day functional outcome.

Humans↗

PubMed2026

Interface-dependent V. parahaemolyticus biofilm under varying temperatures, media, and oxygen conditions: implications for seafood safety.

Vibrio parahaemolyticus biofilms play a critical role in pathogen persistence in marine and seafood-processing environments, where oxygen availability, temperature, and surface interfaces vary widely. This study investigated biofilm development by three strains on partially submerged stainless-steel coupons under gas-liquid-wall (GLW) and fully submerged (SM) interfaces. Viable cell counts (log₁₀CFU/cm2) along with normalized protein concentration per viable cell (nProt) and normalized polysaccharide concentration per viable cell (nPol) were measured, under aerobic and anaerobic conditions across a temperature range of 15-30 °C, using tryptic soy broth with 3% NaCl (TSB) and seawater-based medium (SW). GLW biofilms consistently exhibited higher cell counts (6.4-7.3 log₁₀CFU/cm2) compared to SM biofilms (5.9-6.3 log₁₀CFU/cm2), suggesting that enhanced oxygen diffusion promotes bacterial proliferation. Conversely, SM biofilms exhibited significantly higher nProt and nPol levels (p < 0.001), indicating increased production of the extracellular polymeric substance (EPS) matrix under low-oxygen, high-nutrient conditions. Microscopy and three-dimensional surface plot analyses revealed relatively uniform biofilm layers at the GLW interface, whereas SM biofilms formed heterogeneous, tower-like structures. EPS production was further influenced by medium composition, oxygen, and temperature. SM biofilms grown in SW exhibited significantly higher nProt and nPol than those in TSB under aerobic conditions (p < 0.001), indicating enhanced matrix stabilization. Under anaerobic conditions at 15 °C, nProt and nPol were higher, whereas under aerobic conditions, peak nProt and nPol occurred at elevated temperatures. These findings highlight a trade-off between bacterial growth and matrix production and provide insight into biofilm adaptation and persistence in seafood-processing environments. These insights may help develop improved biofilm control and seafood safety management.

Biofilms↗

PubMed2026

Micro- and nanoplastics-induced neurotoxicity: a CNS-centered, evidence-graded adverse outcome pathway framework based on systematic weight-of-evidence assessment.

Micro- and nanoplastics (MPs/NPs) are ubiquitous anthropogenic particulate pollutants posing emerging threats to human neurological health. Severe heterogeneity in particle physicochemical properties, environmental aging status, exposure paradigms and experimental platforms has created persistent mechanistic uncertainties in MP/NP neurotoxicology, hindering reliable hazard characterization and risk translation. Here, we systematically consolidate empirical toxicological evidence and construct a dedicated central nervous system (CNS)-targeted adverse outcome pathway (AOP) network integrated with rigorous weight-of-evidence (WoE) grading to elucidate the hierarchical, particle-specific toxic cascades underlying MP/NP-induced neural injury. Our synthesis overturns the conventional linear toxicity paradigm, demonstrating that MPs/NPs trigger neurotoxicity via a complex multi-input mechanistic network. We definitively establish oxidative stress as a robust early convergent key event-rather than a universal molecular initiating event-orchestrating ROS overproduction, lipid peroxidation, mitochondrial dysfunction, and neuroinflammation to propagate neuronal damage. This core module is driven by five distinct particulate upstream triggers: particle-biomolecule interfacial perturbation, corona-facilitated cellular internalization, plastic-associated chemical leaching, aging-derived free radical reactivity, and gut-borne systemic neurotoxic signaling. Downstream pathogenic outcomes encompass glial overactivation, neurotransmitter dyshomeostasis, autophagy-lysosome dysfunction, metabolic reprogramming, regulated neuronal cell death, and behavioral impairments. Tiered WoE analysis confirms strong validation for early oxidative/inflammatory cascades, moderate support for gut-brain axis crosstalk and intracellular trafficking disruption, and nascent evidence for synaptic dysfunction and neurodegeneration-linked proteostatic defects. Extrapolation to human health risk remains constrained by the frequent use of high-dose exposure paradigms, limited validated data on internal dosimetry in the human brain, discrepancies between effective concentrations in experimental models and environmentally relevant human tissue burdens, and insufficient causal validation of distal adverse outcomes. We highlight key research priorities including aged mixed-particle exposure systems, leachate-controlled assays, quantitative internal dose evaluation, and mechanistic intervention verification. This evidence-stratified AOP framework resolves longstanding mechanistic ambiguities in particulate neurotoxicity, providing a standardized, causality-based foundation for future mechanistic exploration and health risk assessment of global plastic pollution.

Adverse outcome pathway↗

PubMed2026

Immunomodulatory effects of palm-derived tocotrienol-rich fraction in healthy volunteers following influenza vaccination: A randomised clinical trial.

Most studies on vitamin E and immunity have focused on tocopherols, but the tocotrienol-rich fraction (TRF) from palm oil may exert stronger immunomodulatory effects. This study investigated the effect of various TRF doses on the immune response to influenza immunisation in healthy adults. We hypothesized daily supplementation with lower doses of TRF can boost immune response to the influenza vaccine in healthy Individuals. In a double-blind placebo-controlled trial, 150 participants (≥18 years) were randomised to receive placebo or TRF (50, 100, 200, or 400 mg) daily for 2 months, with vaccination on day 28. Blood samples collected on days 0, 28, and 56 were analyzed for humoral and cellular immunity, antioxidant status, and plasma concentrations of vitamin E. TRF significantly augmented anti-influenza antibody production across all doses, with the 400 mg group exhibiting the highest titers. A selective Th1-type immune response was observed, characterized by significant IFN-γ production upon restimulation in all TRF-supplemented groups compared with placebo. Plasma IL-12 was elevated in the highest dose, whereas the amount of EBI3 produced increased across a broader range of doses compared to placebo. TRF supplementation was associated with increased antioxidant enzyme activities and stable malondialdehyde activity. Elevated α-tocopherol concentrations observed, primarily at higher doses. Supplementation with TRF can enhance immune response to influenza immunisation by modulating humoral, Th1 responses and improving antioxidant status. Critically, antibody production increased similarly across all TRF doses, suggesting that lower doses may offer a cost-effective strategy for supporting humoral immunity, while higher doses provide broader immunomodulatory benefits.

Humans↗

PubMed2026

Muscle Massage Adding Capacitive Resistive Electric Transfer Therapy in Active or Sham Condition for Post-Exercise Recovery in Athletes: A Crossover Clinical Trial.

The increasing demands of elite sports reduce recovery time, impair performance, and increase injury risk. Efficient lactate transport is essential for postexercise recovery. Capacitive resistive electric transfer (CRET) therapy enhances deep tissue heating, induces vasodilation, and promotes circulation. To evaluate whether adding active CRET to a standardized muscle recovery massage, compared with the same massage plus sham CRET, influences indicators of muscle recovery following a maximal anaerobic effort test. A randomized, single-blind, sham-controlled, and crossover clinical trial was conducted in 25 athletes. Participants completed four visits and, after the maximal power and anaerobic capacity test (Wingate test), received a standardized muscle recovery massage combined with either active CRET or sham CRET. Blood lactate levels, muscle oxygenation, muscle thickness, echogenicity, knee extension force, and muscle activity were assessed before and after the test, after treatment, and 24 hours later. Compared with massage plus sham CRET, massage plus active CRET was associated with lower blood lactate concentration at 60 min postexercise (p = 0.029). Ultrasound-derived muscle thickness and echogenicity also differed between conditions at several time points (p < 0.05). However, no significant differences were observed in Wingate test performance, force, muscle activity, and oxygenation between conditions. In athletes performing repeated Wingate exercise, adding active CRET to massage was associated with lower blood lactate concentration at 60 min postexercise and with differences in ultrasound-derived muscle thickness and echogenicity compared with sham CRET plus massage. However, these between-condition differences were not accompanied by clear short-term functional recovery benefits. TRIAL REGISTRATION: NCT06906146.

Humans↗

PubMed2028

Parental son preference in childhood and sex differences in the risk of cardiovascular disease in middle-aged and older adults.

INTRODUCTION: Sex differences in cardiovascular disease (CVD) risk are examined through biological and clinical factors, with less attention to early-life social exposures. This study examined associations of childhood parental son preference with CVD risk, sex differences, and mediation by modifiable risk factors. METHODS: This cohort analysis included China Health and Retirement Longitudinal Study participants aged ≥45 years without baseline CVD. Parental son preference was assessed retrospectively in 2014; incident CVD was self-reported physician-diagnosed heart disease or stroke through 2020. Sampling-weighted, community-clustered Cox models estimated adjusted hazard ratios (aHRs) and 95% CIs. Sex was prespecified as an effect modifier; mediation by 13 risk factors used inverse-odds-ratio weighting. Data were collected from 2011 to 2020 and analyzed from 2025 to 2026. RESULTS: Among 8,079 participants (mean age, 57.5 years; 4,216 women [52.2%]), 1,820 (22.5%) reported parental son preference. Son preference was associated with higher CVD risk overall (aHR 1.23 [95% CI 1.04, 1.46]) and among women (aHR 1.25 [95% CI 1.03, 1.53]); among men, the estimate was 1.16 (95% CI 0.87, 1.56), with limited heterogeneity by sex (ratio of aHRs 1.06 [95% CI 0.72, 1.58]). Among women, risk was concentrated in the highest paternal (aHR 1.47 [95% CI 1.14, 1.90]) and maternal (aHR 1.50 [95% CI 1.12, 1.99]) preference categories. Modifiable risk factors mediated 5.8% (95% CI 1.9%, 9.7%) of the association among women, mainly through socioeconomic and psychosocial factors. CVD risk was highest with both son preference and high risk-factor burden overall (aHR 1.97 [95% CI 1.43, 2.73]) and among women (aHR 2.23 [95% CI 1.61, 3.10]). CONCLUSIONS: Parental son preference was associated with higher incident CVD risk, with the largest estimates in the highest paternal or maternal categories among women. Modifiable risk factors explained a modest proportion, supporting life-course cardiovascular prevention that considers sex-differentiated childhood environments alongside risk-factor modification.

cardiovascular disease↗

PubMed2026

Genomic diversity and thermal niches of Aspergillus molds disrupting rind formation of surface-ripened cheeses.

Filamentous fungi play important roles in the development of surface-ripened cheese microbial communities and contribute to the aesthetics and flavors of these products. Much is known about the diversity and ecology of desirable cheese fungi, but our understanding of the natural history of cheese spoilage molds is limited. The goal of this work was to characterize the genomic diversity of Aspergillus species contaminating artisan cheeses and to identify how the abiotic environment of cheese (the substrate itself and temperature) may constrain the growth of Aspergillus. Comparative genomics identified two main species of Aspergillus, A. westerdijkiae and A. ostianus, as the spoilage molds across three different facilities in the Northeastern United States that experienced contamination events. Multiple genomic types of A. westerdijkiae were found across the different cheese production facilities, indicating that these contamination events are not caused by a single clonal strain. All A. westerdijkiae isolates produced ochratoxin A, but concentrations varied greatly across strains. RNA-sequencing of A. westerdijkiae on nutrient-rich lab media (malt extract agar) versus cheese curd agar identified a suite of pathways enriched in expression on cheese, including degradation of amino and fatty acids. Experiments measuring growth over a range of temperatures identified that spoilage Aspergillus species have a higher optimal growth temperature compared to desirable fungal species in cheese rinds and are outcompeted by Penicillium species at temperatures lower than 15°C. Global fungal metabarcoding databases suggest that A. westerdijkiae is not normally found in natural habitats of the Northeastern United States, and it may be introduced to this region.IMPORTANCEOver the past decade, disruptive contamination events of Aspergillus spoilage molds have occurred at cheese production facilities in Massachusetts, Connecticut, and Vermont in the United States, causing aesthetic, flavor, and potential safety issues. Our work highlights independent introductions of different strains of A. westerdijkiae into multiple cheese facilities and suggests that temperature could be used to control the abundance of Aspergillus spoilage molds. Based on our analysis of the global distribution of A. westerdijkiae, it is not invading cheese facilities from local fungal populations and may be a contaminant in materials used for cheese production.

Aspergillus↗

PubMed2026

Pharmacokinetics and Safety of Nerandomilast in Healthy Volunteers.

BACKGROUND AND OBJECTIVES: Nerandomilast, a preferential phosphodiesterase 4B inhibitor, is approved for idiopathic pulmonary fibrosis and progressive pulmonary fibrosis in some countries. The objective of this study was to evaluate the safety and pharmacokinetics of nerandomilast in healthy volunteers through single- and multiple-rising-dose studies, and a human mass balance study evaluating absorption, distribution, metabolism, and excretion. METHODS: Healthy participants received oral nerandomilast doses ranging from 0.02 mg to 24 mg in the single-rising-dose trial, 1 mg or 6 mg twice daily for 14 days in the multiple-rising-dose trial, and a single oral dose of 18 mg [14C]-labeled nerandomilast in the mass balance trial. In each trial, pharmacokinetic blood samples were collected for determination of nerandomilast plasma concentrations. In the mass balance study, urine, feces, and blood samples were collected, and [14C]-radioactivity was quantified from these matrices. All pharmacokinetic parameters were calculated via noncompartmental analysis. RESULTS: Nerandomilast was rapidly absorbed postadministration, with peak plasma concentrations occurring between 0.5 and 1.25 h postdose before declining in a multiphasic manner. Nerandomilast exposure increased dose proportionally following single- and multiple-dose administrations. Steady state was reached by day 7 after twice-daily dosing with up to 1.69-fold drug accumulation. Following a single oral dose administration of [14C]nerandomilast, 58.0% and 36.4% of radioactivity was excreted in feces and urine, respectively. Of the administered dose, 11.9% was excreted as unchanged parent compound in urine. Nerandomilast safety was acceptable across all three studies and nerandomilast was well tolerated in healthy participants. CONCLUSIONS: Nerandomilast exhibited rapid oral absorption, multiphasic elimination profile, dose-proportional exposure, and was excreted via urine and feces. TRIAL REGISTRATION: NCT01594515 (registered 2012-05-07), NCT01835899 (registered 2013-04-11), and NCT04771286 (registered 2021-02-23).

Humans↗

PubMed2026

Spermidine and melatonin ameliorate heat stress-induced decline in sheep semen quality.

Heat stress impairs reproductive performance in sheep through endocrine disruption and oxidative stress. This study evaluated the protective effects of spermidine (SPD) and melatonin (MT) supplementation on semen quality in Dorper rams during summer. Twenty-four rams were randomly assigned to a control group, an SPD group (5 mg/kg, dietary supplementation), or an MT group (60 mg, subcutaneous implantation) and treated for 60 days. The temperature-humidity index (THI) was monitored throughout the experimental period. Compared with the control group, MT significantly reduced serum cortisol concentration on day 30 (P < 0.05), whereas no significant differences were observed at the other sampling time points. Serum testosterone, spermidine, and melatonin concentrations remained unchanged throughout the study (P > 0.05). SPD supplementation significantly increased ejaculate volume on day 35 and sperm motility on day 42 (P < 0.05), whereas MT did not significantly affect these parameters. Neither treatment reduced the overall sperm abnormality rate. However, both SPD and MT significantly decreased the proportion of acephalic and decaudated sperm on day 56 (P < 0.05). Neither treatment significantly affected pregnancy rate, delivery rate, or the expression of PMFBP1 and SUN5 proteins in semen (P > 0.05). Regarding oxidative stress, MT significantly downregulated CAT protein expression (P < 0.05), whereas SPD significantly reduced MDA content and SOD1 protein expression (P < 0.05); MT showed similar but non-significant trends for these two markers (P > 0.05). Collectively, these findings demonstrate that SPD and MT exert distinct protective effects against heat stress, with SPD improving selected semen quality traits and both treatments reducing sperm head-tail separation, although these benefits did not translate into improved reproductive performance.

Animals↗

PubMed2026

Phenotypic, physiological and transcriptomic analysis of graded salt stress responses in Pyrus betulifolia Bunge and functional characterization of the hub gene PbSTY46.

Pyrus betulifolia Bunge is a salt‑tolerant rootstock for pear, but its salt‑tolerance mechanisms remain largely unknown. In this study, P. betulifolia seedlings were subjected to graded NaCl stress at concentrations of 0 (CK), 50 (T1), 100 (T2), and 200 (T3) mM. We integrated phenotypic observation, physiological assessment, transcriptomic profiling, and functional gene validation to systematically elucidate its salt tolerance mechanisms. Salt stress inhibited seedling growth and root traits in a concentration-dependent manner, and T3 caused the most severe damage. Osmotic solutes responded differentially: soluble sugars peaked under T2, while proline peaked under T3. Antioxidant enzymes showed tissue-specific biphasic responses and declined after prolonged T3 stress. Meanwhile, chlorophyll and photosynthesis decreased, whereas anthocyanin increased, indicating a metabolic shift from photosynthesis to photoprotection. Transcriptome analysis revealed distinct responses depending on stress intensity: mild stress induced membrane lipid remodeling, moderate stress activated circadian rhythm and hormone signaling, and severe stress enhanced phenylpropanoid biosynthesis and thiamine metabolism. Gene Set Enrichment Analysis (GSEA) further highlighted progressive enrichment of phenylpropanoid biosynthesis, heme binding, and oxidoreductase activity. Weighted Gene Co‑expression Network Analysis (WGCNA) identified a blue module significantly positively correlated with root traits, from which the hub gene PbSTY46 was identified. Functional validation via overexpression, loss‑of‑function mutants, and pharmacological interventions (MeJA/DIECA) confirmed that PbSTY46 acts through JA signaling to enhance antioxidant enzyme activities and thereby confer salt tolerance. Collectively, P. betulifolia adopts a "survival‑first" strategy that coordinates growth arrest, osmotic homeostasis, and ROS scavenging. These findings establish PbSTY46 as a key regulator that links JA signaling to antioxidant defense. Thus, PbSTY46 represents a promising candidate for marker‑assisted breeding of salt‑tolerant pear cultivars.

Salt Stress↗

PubMed2026

The effects of nitrate and nitrite supplementation on mitochondrial respiration in permeabilized muscle fibres in young healthy adults.

Nitric oxide (NO) is a direct regulator of mitochondrial respiration. Nitrate (NO3-) and nitrite (NO2-) are good sources of NO, but whether their effects on mitochondrial respiration differ between in vivo and in vitro administration remains unclear. In Study 1, 8 participants consumed NO3- -rich beetroot juice (BR) (∼12.8 mmol NO3-) and NO3- -depleted placebo beetroot juice (PL) (∼0.08 mmol NO3-) acutely and chronically for 2 weeks in a randomised, double-blind, crossover design. A substrate-uncoupler-inhibitor titration (SUIT) protocol was used to assess mitochondrial respiration using high-resolution respirometry (oxygen tension: ∼200-450 μM) in permeabilized muscle fibres. In Study 2, skeletal muscle samples were collected from 11 participants. In a randomised, crossover design, different doses (0, 1.5, and 3.0 μM) of sodium nitrite (NaNO2) were administered to permeabilized muscle fibres. Mitochondrial respiration was measured using the same SUIT protocol under lower oxygen tension (∼50-200 μM). Although muscle NO3- concentration significantly increased after both acute and chronic BR supplementation, mitochondrial respiration and exercise performance did not differ between PL and BR in either condition. Similarly, absolute oxygen flux across different respiratory states were not different between different doses of NaNO2. However, the leak control ratio, reflecting the degree of uncoupling of mitochondrial respiration, was significantly higher with 3.0 μM NaNO2 administration (0.12 ± 0.05) compared to 0 μM NaNO2 administration (0.09 ± 0.04, P = 0.03). These findings, involving both in vivo and in vitro administration approaches, albeit in the presence of relatively high oxygen concentrations, suggest that neither NO3- nor NO2- improves mitochondrial respiration, at least in young healthy adults.

Humans↗

PubMed2026

Prognostic effect of serum glial fibrillary acidic protein and neurofilament light chain for predicting progression independent of relapse activity in multiple sclerosis: A systematic review.

BACKGROUND: Progression independent of relapse activity (PIRA) is increasingly appreciated as one of the important factors contributing to disability accumulation in MS. sGFAP and sNfL could represent markers reflecting two separate biological processes related to relapse-independent progression in MS. OBJECTIVE: To perform a systematic review of the literature on blood GFAP and/or NfL measured in relation to PIRA or other similar relapse-independent progression endpoints in people with MS. METHODS: PubMed, Scopus, and Web of Science databases were searched from inception to 1 June 2026. The eligible studies were original human studies measuring blood GFAP and/or NfL concentrations in serum, plasma, or any other type of blood-derived material and assessing PIRA, PIRMA, CDP/CDW without relapses, relapse-free EDSS progression, non-inflammatory progression, or comparable relapse-independent disability worsening outcomes. Methodological quality was assessed according to the Newcastle-Ottawa scale and the QUIPS instrument for bias detection in the body of evidence on prognostic factors. Due to heterogeneity of outcomes, biomarker measurements and effect estimates, results were synthesized qualitatively rather than quantitatively. RESULTS: After removing duplicates, 1206 records were screened, followed by full-text review of 120 reports. A total of 18 reports were included. Overall, sGFAP was associated more frequently with PIRA or PIRA-like disability progression, particularly in cohorts with suppressed or limited overt inflammatory activity. Evidence for sNfL was more variable and context-dependent: several studies reported associations with PIRA-like or relapse-independent disability worsening when acute inflammatory activity was absent, suppressed, or analytically separated, whereas other studies reported negative or inconclusive findings. Negative or inconclusive results were reported by several articles, particularly when broad outcomes were evaluated or the study population was small. CONCLUSION: Blood GFAP and NfL give complementary but non-interchangeable information concerning PIRA in MS patients. The existing evidence base does not allow us to perform meta-analysis because of heterogeneity in terms of outcomes, standardization of biomarkers, and treatment context. Further prospective investigations with uniform criteria will be necessary for their use as biomarkers of PIRA in clinical settings.

Humans↗

PubMed2026

Intraspecific variation in Bothrops neuwiedi snake venom: Influence of age and sex.

Snake venom is a complex mixture of molecules and is subject to intraspecific variations due to the influence of abiotic and/or biotic factors, one of which is the animal's ontogeny. Some studies have already shown the influence of age on the composition and properties of snake venom, but these variations are not uniform, and each species may exhibit a specific pattern of variation. Therefore, this study aimed to analyze the influence of age on the venom of Bothrops neuwiedi, using 5 age groups, differentiating between males and females. To this end, we analyzed the protein profile of these venoms (using SDS-PAGE, HPLC, and proteomic analyses); enzymatic activities (PLA2, LAAO, and proteolytic activities); coagulant activity, in vivo assays (MDH; LD50 and ED50), and immunorecognition tests (Western blotting and ELISA). Protein profile analysis showed that males exhibited a gradual increase in SVMP and PLA2 concentrations. Both sexes showed a decrease in CTL concentration and a loss of PLA2 activity, which occurred more gradually in males. Proteolytic activity did not show clear ontogenetic differences, but both sexes showed activity peaks in the 2-year-old and senile groups, with females exhibiting higher proteolytic activity than males. Regarding LAAO activity, it increased in males and decreased in females. Although the LD50 did not show age-dependent differences, the venom from the 1-year-old group took longer to cause death in mice but showed a higher hemorrhagic activity than seniles. Furthermore, more antivenom was needed to neutralize the venom from the 1-year-old group than the venom from the senile group; despite this, immunorecognition tests did not show significant ontogenetic variations. In conclusion, the venom of the snake B. neuwiedi undergoes ontogenetic variations with certain sexual differences, showing some peculiarities that have not been found in ontogenetic analyses of other species of the same genus.

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