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Bifidobacterium animalis Subspecies lactis CECT 8145 Affects Markers of Metabolic Health in Dogs During Weight Gain and Weight Loss
No full textThis study explored the effects of Bifidobacterium animalis subspecies lactis CECT 8145 (B. animalis CECT 8145)—in both live probiotic and heat-treated postbiotic form—on metabolic health and digestion in male and female Labrador Retrievers during weight gain and loss. The study consisted of two, seven-week phases: weight gain (200% maintenance energy intake; Phase (1) and weight loss (100% maintenance energy requirement for ideal weight; Phase (2), separated by a 2-week washout period. In each phase, forty-five adult Labrador Retrievers (1.6–12.5 years) were randomly assigned to daily supplementation with live B. animalis CECT 8145 probiotic (PRO, n = 15), heat-treated B. animalis CECT 8145 postbiotic (POST, n = 15), or placebo control (CON, n = 15). Body weight, body condition score, fecal quality and food consumption were monitored throughout the study, and body composition, fecal, and blood samples were analyzed at the beginning and end of each phase. Digestibility was evaluated at the end of each phase. Post-prandial glucose responses were affected by intervention during weight loss, with a 6% reduction in the area under the curve (AUC) in POST compared to CON dogs (p = 0.035). Glucagon was decreased in females supplemented with POST (p = 0.0014), while POST males showed increased glucagon-like peptide-1 (GLP-1) compared to CON (p = 0.016) during weight gain. Serum GGT levels decreased, within the normal reference range, in POST compared to CON dogs during weight gain (post hoc p = 0.041). Fecal isovalerate was also reduced and fat digestibility increased (p = 0.026) in POST compared to CON (p = 0.018) during weight gain. There was a significant association between the group and gastric inhibitory polypeptide (GIP), with a decrease in GIP in POST over time (p = 0.030), and glucagon tended to be decreased in POST compared to CON (p = 0.073). Overall, these findings suggest supplementation with postbiotic B. animalis CECT 8145 may improve certain markers of Labrador retrievers’ metabolic health
Age Structure, Growth Parameters, and Otolith Traits of Two Species of the Genus Trachurus in the Central Mediterranean
No full textThe Atlantic horse mackerel (Trachurus trachurus) and the Mediterranean horse mackerel (T. mediterraneus) are two commercially important species whose biological traits remain insufficiently studied in the Central Mediterranean Sea. This study examines their age, growth pattern, and, for the first time, otolith morphology in both species in the Eastern Ionian Sea. The intercept of the weight–length relationship was a = 0.00599 (95% CI = 0.0050–0.0072) for T. trachurus and a = 0.00801 (95% CI = 0.0072–0.0089) for T. mediterraneus, and the slope was b = 3.121 (95% CI: 3.058–3.183) and b = 2.994 (95% CI: 2.957–3.031), respectively. Age was estimated by counting annual growth increments, visible as alternating opaque and clear bands along the axis of the left sagittal otolith from the core to the posterior margin. Von Bertalanffy growth parameters were estimated as L∞ = 34.65 cm, k = 0.31 year−1, and t0= −1.11 years for T. trachurus and L∞ = 35.98 cm, k = 0.23 year−1, and to = −1.60 years for T. mediterraneus. Otolith morphometrics showed significantly higher values (ANOVA, p-value < 0.05) in T. mediterraneus for all morphometric variables, except one, indicating larger and wider otoliths than those of T. trachurus, which can be a tool to distinguish the two species. A strong correlation was observed between the total length of the body and otolith metrics in both species. This study enhanced our scientific knowledge on the studied species’ life history traits and provides information for further ecological and stock assessment studies
Copper-Induced Thyroid Disruption and Oxidative Stress in Schizopygopsis younghusbandi Larvae
No full textIn recent years, heavy metal emissions in Lhasa have been increasing, which has an impact on the local water environment. The negative effects of copper (Cu2+) on aquatic ecosystems have attracted much attention, as even low concentrations of Cu2+ can exert toxic effects on aquatic organisms. However, the impact of Cu2+ on native fish species from the Lhasa River remains poorly understood. In this study, Schizopygopsis younghusbandi (S. younghusbandi) larvae were exposed to Cu2+ at concentrations of 0. 5, 5, 50, and 500 μg/L for 7 or 14 days to evaluate its toxic effects on thyroid function and the antioxidant system. The results indicate that whole-body total thyroxine (T4) and triiodothyronine (T3) levels were significantly decreased following Cu2+ exposure. This decrease was accompanied by a marked increase in dio1 and dio2 gene expression and decreased expression of thyroid hormone synthesis genes (nis, tg, ttf1 and pax8) after exposure to Cu2+. Furthermore, the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione reductase (GR) and the content of lipid peroxidation were increased, while the content of glutathione (GSH) was decreased. In addition, the survival rates and body lengths of S. younghusbandi larvae were significantly reduced following 7- and 14-day Cu2+ exposure. The Integrated Assessment of Biomarker Response (IBR) analysis further revealed dose- and time-dependent effects of Cu2+ on the larvae. In conclusion, the findings demonstrate that Cu2+ exposure induced disruption of thyroid endocrine and antioxidant systems and caused developmental toxicity in S. younghusbandi larvae
Molecular and Cellular Mechanisms Underlying Domoic Acid-Induced Neurotoxicity and Therapeutic Drugs: A Comprehensive Review
No full textDomoic acid (DA) is a neurotoxic terpenoid compound produced by certain marine algae. It accumulates through the food web and poses a significant threat to humans and animals by selectively targeting hippocampal neurons, leading to neuronal degeneration, necrosis, and subsequent memory impairment. The primary mechanism involves its potent agonism at glutamate receptors, which induces excessive calcium influx, resulting in excitotoxic cell swelling and death. Recent studies have further elucidated the critical role of downstream oxidative stress and other pathogenic factors in DA-induced neurotoxicity. These insights into its multifaceted mechanism have paved the way for novel therapeutic strategies, highlighting promising directions for future treatment development
Patterns and Drivers of Mountain Meadow Communities Along an Altitudinal Gradient on the Southern Slope of Wutai Mountain, Northern China
No full textUnderstanding how plant community characteristics and soil properties vary along altitudinal gradients is essential for ecosystem conservation, restoration, and for predicting ecosystem responses to global environmental change. This study investigated altitudinal patterns and their potential drivers in mountain meadow communities on the southern slope of Wutai Mountain, Northern China. Community characteristics and soil physicochemical properties were measured along an altitudinal gradient ranging from 1800 to 3000 m a.s.l. Most community characteristics exhibited clear altitudinal trends. Species richness, Shannon–Wiener index, Simpson index, aboveground biomass and average plant height all declined significantly with increasing altitude. In contrast, vegetation cover showed a unimodal pattern, initially decreasing and then increasing at higher elevations. Soil physicochemical properties also varied significantly along the altitudinal gradient and were closely associated with changes in community characteristics. Variation partitioning analysis revealed that environmental factors, including altitude and soil properties, explained 71.9% of the total variation in mountain meadow communities. Altitude alone contributed more to community variation than soil factors, indicating its dominant role in shaping community structure. Nevertheless, specific soil properties, particularly soil depth, soil bulk density and soil pH, also exerted significant influences on community characteristics. Overall, our results demonstrate that altitude is a key driver of both vegetation and soil variation in mountain meadows on the southern slope of Wutai Mountain. In addition to altitudinal effects, soil physicochemical properties should be considered when developing conservation and management strategies for mountain meadow ecosystems
Biologic Augmentation for Meniscus Repair: A Narrative Review
No full textMeniscal preservation is increasingly recognized as a critical determinant of long-term knee joint health, yet successful repair remains challenging due to the meniscus’s limited intrinsic healing capacity. The adult meniscus is characterized by restricted vascularity, low cellularity, a dense extracellular matrix, complex biomechanical loading, and a hostile post-injury intra-articular inflammatory environment—factors that collectively impair meniscus healing, particularly in the avascular zones. Over the past several decades, a wide range of biologic augmentation strategies have been explored to overcome these barriers, including synovial abrasion, fibrin clot implantation, marrow stimulation, platelet-derived biologics, cell-based therapies, scaffold coverage, and emerging biologic and biophysical interventions. This review summarizes the biological basis of meniscal healing, critically evaluates current and emerging biologic augmentation techniques, and integrates these approaches within a unified framework of vascular, cellular, matrix, biomechanical, and immunologic targets. Understanding and modulating the cellular and molecular mechanisms governing meniscal degeneration and repair may enable the development of more effective, mechanism-driven strategies to improve healing outcomes and reduce the risk of post-traumatic osteoarthritis
Identification of a Chlorophyll-Deficient Mutant in Maize Associated with Exogenous Vector Insertion
No full textLeaf color mutants are commonly characterized by altered chlorophyll content and aberrant chloroplast development, making them valuable models for investigating photosynthetic mechanisms and chloroplast biogenesis. In this study, an albino mutant was isolated from a population of transgenic maize breeding lines. Genetic analysis indicated that the mutant phenotype is inherited in a Mendelian manner and is controlled by a single nuclear locus. This was supported by a χ2 test performed on the T2 generation, which confirmed a segregation ratio consistent with 3:1 (176:68, χ2 = 1.07 < χ20.05 = 3.84, p > 0.05). Microscopic examination revealed the absence of normally developed chloroplasts in mutant cells. Further expression analysis of chloroplast genes via Northern blotting and quantitative real-time PCR (qRT-PCR) suggested that the mutation impairs the regulation of plastid-encoded polymerase (PEP)-dependent chloroplast gene expression. Notably, PCR-based co-segregation analysis indicated that the mutant phenotype is associated with the entire inserted vector sequence, rather than a point mutation or a small genomic deletion. In conclusion, this paper reports the isolation and phenotypic characterization of an etiolated mutant from a transgenic maize breeding population, including comparative ultrastructural analysis of chloroplasts, co-segregation validation, and chloroplast gene expression profiling. These results enhance our understanding of the physiological and molecular mechanisms underlying chlorophyll-deficient mutations in plants
Computational Study of Hybrid Propeller Configurations
No full textThis study presents the first computational investigation of hybrid propeller configurations that combine toroidal and conventional blade geometries. Using Delayed Detached Eddy Simulation (DDES) with the Shear Stress Transport (SST) k−ω model for flow analysis and the Ffowcs Williams and Hawkings (FW–H) formulation for aeroacoustic prediction, five hybrid propeller designs were evaluated: a baseline model and four variants with modified loop-element spacing. The results show that the V-Gap-S configuration achieves the highest figure of merit (FM), producing over 10% improvement in propeller performance relative to the baseline, while also exhibiting the lowest turbulence kinetic energy (TKE) levels across multiple radial planes. Aeroacoustic analysis reveals quadrupole-like directivity for primary tonal noise, primarily driven by blade tip–vortex interactions, with primary tonal noise strongly correlated with thrust. Broadband noise and overall sound pressure level (OASPL) exhibited dipole-like patterns, influenced by propeller torque and FM, respectively. Comparisons of surface pressure, vorticity, and time derivatives of acoustic pressure further elucidate the mechanisms linking blade spacing to aerodynamic loading and noise generation. The results demonstrate that aerodynamic performance and aeroacoustics are strongly coupled and that meaningful noise reduction claims require performance conditions to be matched
Transcriptome-Wide Profiling of RNA M6A Modifications in Soybean Reveals Shared and Specific Mechanisms of Resistance to Viral and Bacterial Infections
No full textBacterial and viral diseases significantly reduce soybean (Glycine max) yield and quality. RNA modifications, particularly N6-methyladenosine (m6A), are increasingly recognized as having a regulatory role in plant–pathogen interactions, but the m6A methylome of soybean during viral and bacterial infection has not yet been characterized. Here, we performed transcriptome sequencing and MeRIP-seq (methylated RNA immunoprecipitation followed by high-throughput sequencing) of soybean leaves infected with Soybean mosaic virus (SMV) and/or Pseudomonas syringae pv. glycinea (Psg). In general, m6A peaks were highly enriched near stop codons and in 3′-UTR regions of soybean transcripts, and m6A methylation was negatively correlated with transcript abundance. Multiple genes showed differential methylation between infected and control plants: 1122 in Psg-infected plants, 539 in SMV-infected plants, and 2269 in co-infected plants; 195 (Psg), 84 (SMV), and 354 (Psg + SMV) of these transcripts were both differentially methylated and differentially expressed. Interestingly, viral infection was predominantly associated with hypermethylation and downregulation, whereas bacterial infection was predominantly associated with hypomethylation and upregulation. GO and KEGG enrichment analysis revealed shared processes likely affected by changes in m6A methylation during bacterial and viral infection, including ATP-dependent RNA helicase activity, RNA binding, and endonuclease activity, as well as specific processes affected by only one pathogen. Our findings shed light on the role of m6A modifications during pathogen infection and highlight potential targets for epigenetic editing to increase the broad-spectrum disease resistance of soybean
Adenovector 26 Encoded RSV Prefusion F Protein (Ad26.RSV.preF) Does Not Predispose to Enhanced Respiratory Disease in Preclinical Rodent Models
No full textBackground/objectives: RSV is a major cause of mortality in infants, and despite recent progress to prevent RSV in the very young, an RSV vaccine for this population is still highly warranted. Clinical studies in infants in the 1960s using formalin-inactivated RSV (FI-RSV) led to life-threatening enhanced respiratory disease (ERD). Therefore, a thorough safety assessment of RSV vaccine candidates intended for RSV seronegative infants is crucial. Methods: Prior to clinical pediatric development of Ad26.RSV.preF, an adenovirus type 26 vector-encoding RSV F protein stabilized in its prefusion conformation, predisposition to ERD was extensively assessed in cotton rat and mouse models. Results: Cotton rats intramuscularly immunized with a wide dose range of Ad26.RSV.preF, including low and sub-protective vaccine doses, and challenged with vaccine homologous RSV A2 or heterologous RSV B Wash 18537, did not show signs of predisposition to ERD. Histopathology scores for alveolitis, peribronchiolitis, interstitial pneumonia, and perivasculitis after challenge were significantly lower for Ad26.RSV.preF-immunized cotton rats compared to FI-RSV-immunized cotton rats and comparable to or lower than scores in cotton rats intranasally pre-exposed to RSV prior to challenge to mimic natural repeated infection. These results were observed in animals with or without viral replication in the lung after RSV challenge, in the presence or absence of vaccine-induced antibodies. Similar results were observed in mice, where more extensive assessment of mono- and polymorphonuclear cell alveolitis, mucus cell hyperplasia, and mucus accumulation was performed. Conclusions: Based on these extensive analyses, we conclude that there are no indications of ERD predisposition after Ad26.RSV.preF vaccination in rodent models, irrespective of the vaccine dose, challenge virus strain, or presence of viral replication in the lung. These results are crucial for the pediatric development of this vaccine