Search Results (10,343)

High-frequency broadband acoustics can provide fine spatial resolution for near-range fish measurements, but the performance and limitations of beam-position-resolved backscatter measurements require careful evaluation. This proof-of-concept study examined one commercially sourced, dead, previously frozen specimen of each of three cultured fishes: golden pompano (Trachinotus ovatus; 24.4 cm), mandarin fish (Siniperca chuatsi; 29.1 cm), and large yellow croaker (Larimichthys crocea; 31.2 cm). A 650–750 kHz narrow-beam system was referenced to a 10.3 mm tungsten-carbide sphere, and matched-filter pulse compression and 1° stepwise scanning were used to estimate a beam-position-resolved backscatter metric along each body. At broadside incidence, the section-summed backscatter indices were −33.61, −22.45, and −33.07 dB for the T. ovatus, S. chuatsi, and L. crocea specimens, respectively. The section-summed abdominal backscatter index, in the region occupied by the swimbladder in the post-thaw X-ray images, exceeded the arithmetic mean of the head and tail group indices by 9.71 ± 1.84 dB (range: 8.27–11.86 dB). Tailward beam positions fell below the noise floor at approximately 12.5% of the expected scan positions for S. chuatsi and 22.2% for L. crocea. A 15° departure from broadside reduced the section-summed index by 3.73–11.43 dB. Kirchhoff-ray-mode (KRM) simulations based on post-thaw dual-view X-ray geometry were broadly consistent with the specimen-level contrast observed among the preserved specimens, but were 0.92–2.74 dB lower than the corresponding broadside section-summed measurement indices at 700 kHz. These differences are not a quantitative validation because the measured and modeled estimators, frequency weighting, geometry, and tissue parameters were not equivalent. These results demonstrate the feasibility of a calibrated beam-position workflow for preserved specimens, while not establishing live-fish target strength, species benchmarks, or biomass-estimation performance. Full article

In vitro 3D cell culture systems provide a physiologically relevant microenvironment that mimics native tissue architecture. However, establishing functional 3D testicular aggregates in teleosts remains challenging. In this study, we established a novel 3D co-culture aggregate system for olive flounder (Paralichthys olivaceus) primary testicular cells by incorporating the established olive flounder testicular cell (OFT) line. Primary testicular cells alone failed to form 3D aggregates within the first 24 h in ultra-low attachment plates. However, co-culturing with OFT cells rapidly initiated 3D aggregate assembly within 24 h. Furthermore, supplementation with a cocktail of sex hormones and growth factors maintained high cell viability without cytotoxic effects. Notably, quantitative real-time PCR analysis revealed that hormone and growth factor supplementation significantly upregulated the transcript levels of both plzf (2.15-fold) and scp3 (2.34-fold). These results demonstrate that the OFT cell line is essential for facilitating the assembly and incorporation of primary testicular cells into 3D aggregates, while sex hormones and growth factors promote spermatogonial stem cell maintenance and meiotic progression within the aggregates. Overall, this 3D co-culture platform serves as a valuable in vitro tool for fish spermatogonial stem cell research and reproductive biotechnology in aquaculture. Full article

Background/Objectives: Vitamin D deficiency is highly prevalent among children with obesity, but the mechanisms underlying the effectiveness of vitamin D supplementation remain poorly understood. This study examined the expression patterns of VDR-target genes across metabolically diverse tissues and compared these molecular measures with circulating serum 25-hydroxyvitamin D (25OHD), the current clinical marker of vitamin D status. We hypothesized that VDR-pathway gene expression would correlate within metabolically relevant tissues but would not be significantly associated with circulating serum 25OHD levels. Methods: A secondary analysis was performed on blood, intestinal, and visceral and subcutaneous adipose tissue (VAT and SAT, respectively) samples obtained from adolescents with obesity. Subject data included age, gender, race/ethnicity, and BMI. The tissues were analyzed via real-time qPCR to obtain quantitative levels of VDR-target gene expression, which included TLR4, THBD, and VDR in SAT and VAT and TRPV6, S100G, and VDR in intestinal tissue. Blood samples were analyzed for serum 25OHD. Results: Gene expression of THBD, VDR, and TLR4 in SAT and VAT significantly correlated with each other. In intestinal tissue, there was significant correlation between TRPV6, S100G, and VDR. No statistically significant associations were identified between the gene expression levels and serum 25OHD levels. Conclusions: VDR-target gene expression levels correlated with each other across diverse tissues but not with serum 25OHD levels. This discrepancy suggests that circulating 25OHD concentrations may not fully reflect vitamin D action. Full article

Objectives: Advanced 3D volumetry is increasingly utilized to predict postoperative outcomes. It is widely hypothesized that remnant pancreatic volume and progressive atrophy dictate the loss of endocrine function after pancreaticoduodenectomy (PD). This study aims to investigate this anatomical paradigm by evaluating whether 3D volumetric tissue loss or the baseline metabolic load drives new-onset diabetes mellitus (NODM). Materials and Methods: This retrospective study included 159 non-diabetic patients who underwent PD. Preoperative and postoperative (6-month) computed tomography (CT) images were evaluated using Synapse 3D 6.7 version volumetric analysis software to calculate total pancreas volume, remnant volume, and postoperative progressive atrophy rate. All measured volumes were indexed to body weight. Factors associated with NODM were analyzed using multivariate logistic regression and ROC analysis. Results: Postoperative follow-ups revealed that 30.2% (n = 48) of the patients developed NODM. Interestingly, advanced 3D volumetric analysis revealed no significant differences between the diabetic and non-diabetic cohorts regarding body weight-indexed total pancreas volume, preoperative remnant volume, or postoperative progressive atrophy rate (p = 0.475). Instead, multivariate analysis identified the preoperative metabolic load, represented by Body Mass Index (BMI), as the sole independent predictor of NODM (p = 0.006, OR = 1.125), independent of surgical tissue loss. ROC analysis demonstrated a moderate predictive threshold for BMI > 26.5 kg/m² (AUC = 0.644). Conclusions: In this cohort, the anatomical volume and progressive atrophy of the remnant pancreas, despite precise 3D quantification, were not statistically associated with the development of NODM after PD. Postoperative endocrine failure appears to be strongly associated with the patient’s baseline metabolic stress rather than solely the physical extent of surgical tissue loss. These findings suggest that while anatomical tissue preservation remains biologically important, preoperative metabolic risk stratification should be a clinical priority. Full article

Background/Objectives: Shape-memory biodegradable scaffolds (4D scaffolds) represent promising platforms for minimally invasive tissue engineering and localized drug delivery. This study investigated how two different fabrication techniques, electrospinning (ES) and extrusion-based direct ink writing (DIW), influence the structural, thermal, mechanical, shape-memory, and drug-release properties of poly(L-lactide-co-caprolactone) (PLA/PCL 70:30) scaffolds loaded with dexamethasone (DXM). Methods: DXM-loaded PLA/PCL 70:30 scaffolds were fabricated by ES and DIW. The resulting matrices were characterized in terms of morphology, mass, thickness, drug-loading efficiency, thermal properties by differential scanning calorimetry, shape-memory performance, tensile mechanical properties, and in vitro DXM release. Results: Both fabrication techniques produced DXM-loaded matrices with comparable mass and thickness and high loading efficiencies (>82%). Glass transition temperatures ranged between 33 and 39 °C, supporting thermally induced shape recovery under physiologically relevant conditions, while ES processing was associated with higher polymer crystallinity. All scaffolds exhibited shape-memory behavior, with recovery ratios exceeding 90%. ES scaffolds displayed a microporous nanofibrous architecture, whereas DIW scaffolds showed a more open and highly porous structure. These morphological differences were reflected in their mechanical behavior: ES scaffolds exhibited higher tensile strength (up to 16.5 MPa vs. 1.9 MPa) and elongation at break (up to 320% vs. 243%). Drug-release profiles were also fabrication-dependent, with ES scaffolds reaching a plateau at approximately 80% DXM release, whereas DIW scaffolds showed near-complete release within 48 h. Conclusions: Both fabrication approaches preserved the thermoresponsive shape-memory behavior of PLA/PCL 70:30 but generated distinct scaffold architectures that strongly influenced mechanical performance and DXM-release kinetics. Full article

Glycation and reactive carbonyl stress are protein-modifying processes associated with skin aging, but how they alter local tissue mechanics and deformation-prone behavior remains unclear. Here, reconstructed human epidermis (RHE) and three-dimensional (3D) collagen gels were used as epidermal-like and collagen-rich skin surrogate compartments. Nanoindentation mapping showed that accelerated glycation and carbonyl stress increased the effective Young’s modulus and stiffness heterogeneity in both models, with 2.34–5.85-fold increases in the mean modulus and 1.09–1.31-fold increases in normalized neighbor contrast across four treatment–model combinations: glycated RHE, glycated 3D collagen gel, carbonyl-stressed RHE and carbonyl-stressed 3D collagen gel. Nanoindentation-derived stiffness profiles were incorporated into reduced-order virtual bilayer nonlinear post-buckling simulations. Under imposed end-shortening strains of 1%, 5%, and 10%, glycation- and carbonyl-stress-informed bilayers showed increased predicted peak curvature and localized folding index values. Profile-control simulations were then used to separate average stiffening from spatial stiffness variation. Uniform-mean profiles failed to reproduce the curvature localization response, whereas heterogeneity-preserving mean-matched profiles retained elevated curvature-based outputs. These findings suggest that spatial stiffness heterogeneity, rather than stiffening alone, contributes to predicted curvature localization in skin surrogate bilayers. Beyond mechanistic insight, the nanoindentation–simulation workflow may provide a mechanics-based readout for evaluating prospective cosmetic interventions. Full article

Colorectal cancer (CRC) remains a major cause of cancer morbidity and mortality. Immune checkpoint inhibitors (ICIs) have transformed the treatment of microsatellite instability-high/mismatch repair-deficient (MSI-H/dMMR) CRC, yet most CRCs are microsatellite-stable/mismatch repair-proficient (MSS/pMMR) and remain poorly responsive to immunotherapy. MicroRNAs (miRNAs) are well positioned to influence this biology because individual miRNAs can coordinate multiple tumor-intrinsic and microenvironmental programs that shape antitumor immunity. Rather than cataloging miRNAs one by one, this review organizes the evidence around the major barriers that sustain an immune-cold CRC microenvironment: altered checkpoint and costimulatory signaling, defective antigen presentation, impaired effector T-cell access and function, suppressive myeloid and stromal compartments, and extracellular vesicle (EV)-mediated intercellular communication. We also critically assess tissue and circulating miRNA signatures as candidate biomarkers of ICI response and discuss therapeutic approaches based on miRNA mimics, inhibitors, and targeted delivery platforms. The available evidence supports a biologically compelling role for miRNA networks in CRC immune regulation, but clinical translation remains limited by context dependence, delivery, off-target effects, and the lack of treatment-linked validation in CRC cohorts. Full article

Microbial keratitis requires rapid diagnosis to enable timely, pathogen-directed treatment. Corneal confocal microscopy (CCM) is used to quickly diagnose acanthamoeba and fungal keratitis, but it relies on undesirable contact objective lenses, and no supplier has maintained a stable market presence. Here, we present a preliminary investigation of the potential abilities of non-contact optical coherence microscopy (OCM) as an emerging alternative technology. Using an ex vivo porcine corneal infection model, we demonstrate that OCM can produce en face images, similar to CCM, as well as 3D visualizations of fungi hyphae in stromal tissue. Like CCM, bacterial pathogens were too small to directly identify in OCM images. Nevertheless, OCM detected that ex vivo infection induced systematic changes to the stroma that are consistent with the breakdown of keratocyte structure. These proof-of-concept results demonstrate the potential of non-contact OCM for imaging microbial keratitis and support further in vivo evaluation. Full article

Background/Objectives: Dermatosparaxis Ehlers–Danlos syndrome (dEDS) is a rare autosomal recessive connective tissue disorder caused by biallelic pathogenic variants in ADAMTS2, which encodes the primary N-proteinase responsible for fibrillar procollagen processing. Although defective procollagen cleavage is the defining molecular feature of dEDS, how ADAMTS2 deficiency disrupts extracellular matrix (ECM) organization and tissue integrity remains incompletely understood. Here we characterized the structural, molecular, and cellular consequences of a knock-in Adamts2 mouse model harboring a disease-associated variant and assessed its phenotypic and mechanistic resemblance to human dEDS. Methods: We generated Adamts2^Q226* mice carrying a variant analogous to a human dEDS-causing mutation. Skin from homozygous, heterozygous, and control animals was evaluated using histologic, ultrastructural, biochemical, digital pathology, and single-nucleus RNA-sequencing approaches. Pathway enrichment analyses and the computational tool CellChat were used to infer altered molecular programs and changes in intercellular communication. Results: Homozygous knock-in mice exhibited near-complete loss of dermal ADAMTS2 protein expression, impaired type I procollagen processing, disrupted dermal architecture, and irregular hieroglyphic collagen fibrils characteristic of dEDS. Digital pathology demonstrated reduced collagen bulk, diminished assembled and total collagen, increased fine collagen, and loss of mature collagen architecture, with intermediate changes in heterozygous animals. Single-nucleus RNA sequencing identified fibroblasts as the most affected population, with coordinated downregulation of collagen, microfibrillar, and other ECM-associated genes. Pathway analyses implicated altered ECM organization, receptor-linked signaling, cytoskeletal regulation, protein processing, and metabolism, while CellChat inferred widespread reductions in intercellular communication. Conclusions: ADAMTS2 deficiency causes fibroblast-enriched transcriptional remodeling, impaired collagen processing and ECM maturation, and disrupted tissue-wide cellular communication. This model provides a translational platform for studying dEDS pathogenesis and strategies to restore ECM homeostasis. Full article

Magnetic hyperthermia is a promising therapeutic technique in which magnetic nanoparticles (MNPs) generate heat when exposed to a high-frequency alternating magnetic field. The magnetic dipolar interactions between magnetic nanoparticles play an important role in the relaxation dynamics and overall magnetic heating efficiency. In this work, the thermal response of a tumoral tissue was studied considering the dipole–dipole interactions in chain-like nanoparticle assemblies. A 3D space–time model implemented in COMSOL Multiphysics 6.2 is used to investigate the temperature field and thermal damage in tumoral tissue considering magnetic relaxation mechanisms for both (i) parallel and (ii) perpendicular anisotropy configurations with respect to the applied magnetic field. Dipole–dipole interactions significantly modify the effective energy barriers involved in magnetic relaxation mechanisms, when nanoparticles are closely spaced. Interparticle spacing and MNP size are two very important parameters that influence the effective anisotropy barrier and, implicitly, the heating efficiency of magnetic nanoparticles. Moderate dipolar interactions lead to optimal SAR values, while strong interactions reduce heating efficiency due to magnetic locking. This study provides guidelines for the design of magnetic nanoparticles for hyperthermia applications. Full article

Agarose is a thermoreversible, highly biocompatible polysaccharide increasingly used in tissue engineering (TE). Its molecular architecture, optical clarity, tunable mechanics, and chemical inertness make agarose hydrogels attractive scaffolds for generating bioartificial tissues by TE. This review summarizes current knowledge on agarose extraction, purification, structural variants, and physicochemical properties regarding gelation behavior, stiffness, porosity, and bioactivity. We discuss how agarose type and concentration critically determine hydrogel biomechanical and optical performance, influencing cell behavior and in vivo suitability. Although biologically inert, agarose can be functionalized or combined with fibrin, collagen, chitosan, and other biomaterials to enhance cell adhesion, proliferation, and differentiation. Diverse biofabrication approaches—including micromolding, bead production, 3D bioprinting, and de novo assembly of cells, biomaterials and bioactive factors—have enabled the generation of microtissues, organoids, and complex multilayered constructs. Agarose-based biomaterials allowed for the successful generation of bioartificial substitutes of cartilage, bone, adipose tissue, skin, cornea, oral mucosa, and the peripheral nerve, with several fibrin-agarose advanced therapy medicinal products (ATMP) already reaching clinical application, including the skin substitute UGRSKIN, the artificial cornea NANOULCOR and the palate mucosa BIOCLEFT. Together, current evidence positions agarose as a versatile and translationally relevant biomaterial for next-generation TE, warranting further exploration of its potential in additional therapeutic contexts. Full article

Liver tumor segmentation is a significant task in clinical imaging that involves detecting liver tumors and distinguishing them from the surrounding liver tissue in CT scans. Precision segmentation performs important roles in the initial detection of liver cancer, treatment planning, and monitoring disease development, which also supports doctors, facilitating surgeries and radiation therapy more efficiently. Meanwhile, clinical imaging and segmentation algorithms have been enhanced over the years. The currently prevailing state-of-the-art methods still face multiple difficulties, though, in obtaining precision and reliability in their outcomes. Tumors with irregular shapes, variable sizes, and densities similar to those of surrounding tissues often lead to segmentation inaccuracies and potential misdiagnoses. In this work, we tackle these challenges by developing an advanced process for precise liver tumor segmentation by utilizing CT images from the LiTS dataset. The proposed DTARNU-Net was developed, trained, validated, and evaluated exclusively using the Liver Tumor Segmentation (LiTS) benchmark dataset. No experiments were conducted on the 3D-IRCADbI dataset in this study. All quantitative and qualitative results presented in the manuscript correspond to the LiTS dataset. The LiTS dataset contains contrast-enhanced abdominal CT scans with expert-annotated liver and tumor masks. The proposed model was evaluated using patient-level training, validation, and testing partitions (9:2:2 ratio), and all experiments were independently repeated five times. Statistical significance was assessed using paired Student’s t-test (p < 0.05), and the results confirmed that the performance improvements over competing methods are statistically significant. We introduce a novel three-level pre-processing approach that significantly enhances image quality through histogram equalization, noise removal, smoothing, and sharpening. Our approach is embodied in the Dense Tiered Attention Residual Nested U-Net (DTARNU-Net), a sophisticated model combining the strengths of a Siamese network and a nested U-Net architecture. This model incorporates the ACON-ReLU residual convolution block (A-R), which improves recognition accuracy in regions with subtle changes, reducing missed detection. The presented method enhances trait collaboration and spatial data by utilizing the Brownian Motion-based Butterfly Optimization Algorithm (BM-BOA). This algorithm efficiently integrates low-level trait details with high-level semantic data. The Dense Tiered Attention Residual Module (DTSRM) additionally improves these traits to obtain more precise segmentation. The model achieved segmentation robustness of 96.78% for liver segmentation and 97.00% for liver tumor segmentation on the LiTS dataset. These outcomes indicate that the presented method performs better than the prevailing state-of-the-art methods and has the capability to help computer-assisted detection and treatment by furnishing more precise and reliable liver tumor segmentation. Full article

Calcific aortic valve disease (CAVD) is a progressive condition driven by oxidative stress, chronic inflammation, and the osteogenic reprogramming of valvular interstitial cells, leading to hydroxyapatite crystallization. Because tissue non-specific alkaline phosphatase (TNAP) drives phosphate-mediated mineralization, this study evaluated the efficacy of novel TNAP inhibitors as a disease-modifying strategy. Using a vitamin D3-induced CAVD mouse model presenting human-like annular thickening and valvular calcification, we analyzed the therapeutic impact of these inhibitors. TNAP expression was highly elevated in diseased valves; however, inhibitor treatment significantly lowered TNAP levels and attenuated valvular calcification. Notably, the inhibitors suppressed lipid peroxidation and restored antioxidant capacity, significantly regulating GSH, SOD, and CAT levels while decreasing lipid oxidation markers (MDA, 4-HNE, MPO). Furthermore, pro-inflammatory cytokines (IL-1β, TNF-α) and apoptotic markers (cleaved Cas-3, cleaved PARP) were markedly decreased, accompanied by diminished fibrotic and osteogenic remodeling, while maintaining normal bone homeostasis. In conclusion, TNAP inhibition effectively reduces pathological valve calcification by suppressing interconnected oxidative, inflammatory, fibrotic, and osteogenic pathways, positioning it as a promising and safe therapeutic approach for CAVD. Full article

Three-dimensional (3D) printing and bioprinting technologies are increasingly used in tissue engineering and in the development of personalized medical devices with tailored biological and mechanical properties. Despite their advantages, these technologies may involve exposure to chemical compounds with uncertain biological effects, including potential endocrine-disrupting activity. This study aims to evaluate the hormonal activity and cytotoxicity of various materials commonly used for 3D printing technologies, including thermoplastics and synthetic materials (PLA, ABS, PCL, b-TPUe, PVA, PEGDA), and biomaterials (collagen, alginate, hyaluronic acid, agarose, silk fibroin, GelMA, HAMA). Hormonal activity was evaluated using the E-screen assay for estrogenic and anti-estrogenic activity, and the PALM assay for androgenic and anti-androgenic activity. Cytotoxic effects are evaluated by assessing cellular metabolic viability using the MTT assay. No detectable estrogenic, anti-estrogenic, androgenic, or anti-androgenic activity, nor any signs of cytotoxicity, were observed within the experimental conditions analysed. This study represents the first analysis of some specific endocrine-related endpoints of a wide range of 3D printing and bioprinting materials, and should not be interpreted as definitive proof of the complete absence of endocrine activity. Further studies addressing additional toxicological parameters and long-term assessments are required to comprehensively characterize their safety and suitability. Full article

Replicating the complex physiology of human skin in vitro remains a challenge for cutaneous oncology. Although several three-dimensional (3D) skin and melanoma models have been developed, reproducible skin equivalent systems that enable direct and standardized comparisons between healthy and melanoma-containing skin remain valuable experimental tools. This study aimed to optimize and characterize skin equivalents containing either melanocytes or melanoma cells and to evaluate their utility as platforms for investigating melanoma-associated skin biology and UVB-induced responses in vitro. To achieve this, 3D skin equivalents containing fibroblasts, keratinocytes, and either melanocytes or melanoma cells were reconstructed on a polystyrene scaffold to generate healthy (mc) and melanoma (mm) models. Morphological characteristics were compared with clinically verified human tissue sections, and functional responses to UVB irradiation were assessed with a focus on the kynurenine pathway. The models demonstrated a distinct dermal–epidermal architecture and distinguishable melanoma-associated features, including epidermis-confined melanoma cell clusters, in mm constructs. UVB exposure induced differential responses between models, including significant differences in kynurenine pathway regulation. These findings suggest that the developed skin equivalents provide a reproducible in vitro platform for studying melanoma-associated skin biology and treatment-related metabolic responses and may support future mechanistic studies of skin cancer progression. Full article