Biology-Basel最新文献

Cardiovascular disease has become the leading cause of death worldwide, underscoring the urgent need for widespread cardiac monitoring, while the Electrocardiogram (ECG) remains the diagnostic gold standard, the complexity of its acquisition limits its long-term feasibility. In contrast, Photoplethysmography (PPG), ubiquitous in wearable devices, is increasingly adopted due to its accessibility. However, synthesizing ECG from PPG poses an intrinsically ill-posed inverse problem. Existing purely data-driven paradigms often neglect underlying biophysical mechanisms, resulting in a lack of physical constraints and interpretability, which renders them prone to generating non-physiological hallucinations. To address this, we propose PhysDiff-LBM, a novel physics-aware framework that incorporates Lattice Boltzmann hemodynamic constraints into a conditional diffusion model. Employing a dual-stream architecture, our framework captures high-frequency morphological details via a cross-attention-guided diffusion model with region-wise adaptability. Synergistically, we physically regularize the ECG synthesis by leveraging the mesoscopic streaming and collision operators of LBM. By forcing the synthesized waveform gradients to evolve consistently with hemodynamic momentum, this mechanism constrains the model to strictly adhere to the fluid dynamic conservation laws governing pulse wave propagation. Experimental results demonstrate that our method achieves superior signal fidelity and exhibits significant advantages in downstream clinical applications.

The genus Meristotheca (Gigartinales, Solieriaceae) comprises edible red algae that are economically important food ingredients in Korea, Japan, and China. In Korea, two species, Meristotheca coacta and Meristotheca papulosa, have been identified, with the latter being predominantly reported. Recently, molecular phylogenetic analysis enabled the identification of Meristotheca pilulaora (Gigartinales; Solieriaceae) on Jeju Island (Korea). In this study, we used a DNA barcoding method to re-examine M. papulosa herbarium specimens deposited at the National Institute of Biological Resources (Incheon, Korea). Specimens were collected from Korean coastal regions between 2009 and 2019. Molecular analyses based on the rbcL and cox1 sequences of the "M. papulosa" herbarium specimens revealed that the specimens were of two other species, M. pilulaora and Gracilaria textorii (Gracilariales; Gracilariaceae). Our work represents a case study for establishing a misidentification at the inter-ordinal level among herbarium specimens without DNA sequence verification. Moreover, we developed a molecular marker for the effective species-level identification of M. pilulaora and G. textorii specimens. The DNA barcoding method provides useful information regarding M. pilulaora distribution and taxonomy.

The vaginal microbiome (VM), a complex and dynamic microbial ecosystem, is now recognized as a central determinant of female reproductive and gynecologic health. Under homeostatic conditions, a Lactobacillus-dominant ecosystem maintains vaginal acidity, provides colonization resistance, and modulates mucosal immunity. Conversely, vaginal dysbiosis-characterized by Lactobacillus depletion and anaerobic or aerobic overgrowth-is associated with infectious vaginitis, increased susceptibility to sexually transmitted infections, and non-infectious conditions such as genitourinary syndrome of menopause. This review provides an integrated overview of the composition, functional characteristics, and host interactions of the VM across health and disease. We highlight major mechanisms by which microbial dysbiosis contributes to disease pathogenesis, including biofilm formation, altered microbial metabolism, and immune dysregulation. In addition, we discuss the translational potential of the VM as a source of diagnostic and prognostic biomarkers and as a target for emerging microbiome-dependent therapeutic strategies. Collectively, current evidence supports the view that vaginal dysbiosis is a heterogeneous and context-dependent state driven by distinct pathogen- and host-related mechanisms, underscoring the importance of prioritizing microbiome restoration rather than pathogen eradication alone.

Intravenous delivery of recombinant adeno-associated virus serotype 9 can lead to reporter activation in cell types beyond the vasculature, but the routes enabling downstream parenchymal labeling remain unclear. Here, we provide a systematic, time-resolved map of parenchymal labeling after a single intravenous dose of rAAV9 encoding Cre recombinase under a ubiquitous promoter in healthy adult Ai9 reporter mice. Following retro-orbital administration, we quantified tdTomato-positive labeling across 25 targets at multiple time points over six months and observed durable reporter activation in several nonvascular parenchymal populations relevant to systemic gene-delivery applications. We also identify a set of parenchymal cell types that are consistently labeled in both this vascularly initiated reporter system and our prior adult VE-cadherin-driven reporter paradigm, supporting a connection to vascular exposure without asserting lineage relationships. These results nominate mechanistic routes for future disambiguation, including viral transcytosis across endothelium, endothelial cell transdifferentiation and extracellular-vesicle-mediated transfer. The dataset and methods provide a reference framework for investigators optimizing systemic delivery and interpreting downstream labeling in vivo.

V. parahaemolyticus has several virulence factors, including thermostable direct hemolysin (TDH), TDH-related hemolysin (TRH), and two separate type III secretion systems (T3SSs), T3SS1 and T3SS2. T3SS1 is responsible for cytotoxicity, primarily through the activity of its effector VP1680. To gain a detailed understanding of the relationship between the amount of effector, its expression timing, and cytotoxicity, a system is required to regulate protein expression levels and timing. In the present study, we developed an effector protein expression system controlled by an arabinose-dependent transcription factor and found that cytotoxicity toward mammalian cells increased in a VP1680-dependent manner. To ensure specific protein degradation, we also established a targeted protein degradation system, including VP0917 (ClpP) and VP0918 (ClpX)-, or VP0917 and VP1014 (ClpA)-mediated degradation of ssrA-tagged proteins (proteins bearing the C-terminal degradation tag encoded by tmRNA). By combining these systems, more than 50% of the targeted protein could be degraded within 20 min. As a byproduct of creating the systems, we obtained an enhanced green fluorescent protein variant that emits strong fluorescence in V. parahaemolyticus. The protein degradation system developed in this study has demonstrated the potential to control intracellular protein levels to a certain extent. Moreover, experimentally controlling intracellular protein levels will allow for a more detailed examination of the relationship between protein quantity and cellular phenotype, potentially overcoming the limitations of the "all-or-nothing" model.

The greater horseshoe bat (Rhinolophus ferrumequinum), which is widely distributed across the temperate regions of China, primarily consists of two major evolutionary lineages: a northeastern (NE) lineage with a hibernation period of 6-8 months and a central-eastern (CE) lineage with a hibernation period of 4-5 months. This study conducted a comparative analysis of liver transcriptomes from these two lineages during the active, torpor, and arousal phases. The results indicated that the CE lineage exhibited a significantly greater number of differentially expressed genes (DEGs) compared to the NE lineage. During the torpor phase, both lineages transitioned from carbohydrate metabolism to lipid metabolism, substantially downregulating genes and pathways associated with amino acid metabolism, and upregulating immune-related genes to maintain essential defense functions. In the arousal phase, both lineages only moderately activated several genes associated with immunity and metabolic regulation to facilitate a rapid return to torpor. Notably, the number of DEGs co-regulated between the two lineages was very limited, and a large number of lineage-specific regulatory genes related to energy and metabolism were identified. This may reflect the adaptability of different bat lineages to the local environment, highlighting the importance of habitat conditions in lineage differentiation. Therefore, hibernation induces substantial transcriptomic reorganization in the liver of R. ferrumequinum, particularly affecting metabolic and immune processes. Distinct geographic lineages exhibit unique hibernation adaptation strategies through the regulation of specific genes and pathways. This study enhances the understanding of the molecular mechanisms underlying hibernation adaptation across different evolutionary lineages of the same species at the transcriptomic level, providing insights into the evolutionary adaptations of animals to environmental changes.

Rearing density influences pig productivity and welfare, but its behavioral and physio-logical effects remain unclear. This study evaluated how increasing space allowance from 0.57 to 0.97 m²/pig affects growth, agonistic behavior, and stress in growing pigs. Seventy-six 12-week-old pigs were allocated to high or low rearing density (HRD: 12 pigs/pen, n = 4 pens; LRD: 7 pigs/pen, n = 4 pens) for 28 days by varying pig numbers within identical pens. Growth performance was recorded weekly, while agonistic behavior was continuously monitored using RGB cameras and detected with a YOLOv8-based model (overall mAP50 = 0.953; aggression = 0.960, ear biting = 0.927, tail biting = 0.972). Ear base temperature was measured at baseline and twice weekly, lesion scores were assessed at trial completion, and blood biochemical parameters were also assessed. Pigs under LRD exhibited higher (p < 0.01) body weight, daily gain, and feed intake, with a lower feed conversion ratio than HRD pigs. Increased space allowance reduced (p < 0.05) agonistic behavior, lesion scores, plasma glucose, free fatty acids, cortisol, and ear base temperature. These findings indicate that increased space allowance improves growth and welfare and demonstrate the value of AI-based behavioral monitoring in pig production systems.

To decipher the molecular response mechanism of melon to saline-alkaline stress, seedlings of the melon cultivar "Xikaixin" were treated with 50 mmol·L^-1 mixed solutions of NaCl and NaHCO₃ at ratios of 1:1, 1:2, and 2:1 to simulate saline-alkaline stress. Transcriptome sequencing of roots (four biological replicates per group, with each replicate consisting of one pot containing four robust seedlings as the experimental unit) yielded 78.98 Gb of clean data (≥6.02 Gb per sample) with Q30 ≥ 96.61% and genome alignment rates of 97.00-98.02%, identifying 588, 686, and 1107 differentially expressed genes (DEGs) in the 1:1, 1:2, and 2:1 groups, respectively. Notably, the 1:1 treatment-mimicking the natural NaCl:NaHCO₃ ratio of saline-alkaline soil in southern Xinjiang-had 588 DEGs with the plant hormone signal transduction pathway as its most significantly enriched pathway, representing the core molecular response of "Xikaixin" to near-natural saline-alkaline stress. DEGs were significantly enriched in 50 pathways categorized into five major classes, with the plant hormone signal transduction pathway showing the highest enrichment across all treatments. A key observation from gene expression patterns is a potential auxin-ABA balance modulation, inferred from the differential expression of annotation-based auxin-related and ABA-related genes/pathways (no direct measurement of hormone levels or signaling was performed): two auxin-related genes (auxin-induced protein gene MELO3C013403 and auxin response factor gene MELO3C004381) were specifically upregulated (≥two fold vs. control) in the high-salt 2:1 group, while ABA-related genes were upregulated and auxin/jasmonic acid/gibberellin-related genes were downregulated in the 1:2 group, indicating a putative cultivar-specific hormone-related gene expression pattern associated with auxin-ABA crosstalk in "Xikaixin" under saline-alkaline stress. In contrast, photosynthesis-antenna protein genes (e.g., MELO3C021567) were significantly downregulated (to 32% of the control) under the 2:1 treatment. RT-qPCR validation confirmed the consistency of these candidate genes' expression with transcriptomic data. Therefore, melon may respond to saline-alkaline stress by regulating the plant hormone signal transduction (especially auxin-ABA balance), photosynthesis, and carbon metabolism pathways. This study provides novel candidate genes and a theoretical basis for the genetic improvement of saline-alkaline-tolerant melon cultivars, with the unique auxin-ABA balance modulation as a key original contribution.

Non-specific lipid transfer proteins (nsLTPs) play a crucial role in lipid transport across membranes, contributing to cellular integrity and structural stability. These proteins are characterized by the presence of eight conserved cysteine residues that form four disulfide bonds and a hydrophobic cavity that is essential for lipid binding and transport. Interactions of nsLTPs with diverse ligands enable them to participate in key biological processes, including signal transduction, protein folding, membrane stabilization, and cell wall organization. Additionally, these proteins are integral to plant responses to abiotic and biotic stresses and to developmental processes, including growth, germination, and flowering. The interaction between nsLTPs and plant signaling molecules activates regulatory networks that modulate stress-responsive gene expression, reinforcing plant resilience under adverse conditions. Despite their functional significance, the evolutionary trajectory, subcellular localization, and regulatory mechanisms governing nsLTP expression remain limited, as reflected in previous reviews on nsLTPs. This review provides a comprehensive analysis of nsLTP evolution, roles in plant defense and signaling, functional diversity, updated subcellular localization, and future research directions based on recent findings.

The identification of species complexes in freshwater snails remains challenging due to limited diagnostic morphological characters and incomplete taxonomic knowledge in many taxa. Within the family Bithyniidae, species have traditionally been classified using shell morphology and genital anatomy to distinguish intraspecific variation from interspecific differences. However, extensive morphological plasticity has hindered reliable species delimitation, and the presence of cryptic diversity further complicates taxonomy. Recent DNA barcoding studies of Hydrobioides have provided evidence of such cryptic diversity, highlighting the need for taxonomic reassessment within the genus. In the present study, we examined morphological variation in Hydrobioides nassa from Thailand in conjunction with mitochondrial DNA sequence data. Molecular phylogenetic analyses based on cytochrome c oxidase subunit I (cox1) sequences revealed three well-supported genetic lineages within H. nassa, accompanied by high levels of pairwise genetic divergence. Morphological comparisons of shell, operculum, and radular characters further supported differentiation among these lineages, although some characters showed overlap. While Hydrobioides has previously been regarded as comprising a single morphologically defined species, our results demonstrate that H. nassa represents a complex of genetically distinct lineages with subtle but consistent morphological differences. This study highlights the importance of integrating molecular approaches with traditional morphological analyses to improve taxonomic resolution and to better understand biodiversity within freshwater snail groups exhibiting cryptic diversity.