Search Results (1,045)

Staphylococcus aureus, particularly methicillin-resistant S. aureus (MRSA), remains a leading cause of skin and soft tissue infections (SSTIs) worldwide. Patients with renal edema, including those with nephrotic syndrome and chronic kidney disease (CKD), and critical illness, are particularly susceptible because of barrier dysfunction, immune impairment, and altered antimicrobial pharmacokinetics. This narrative review examines the mechanisms linking renal edema to increased susceptibility to cutaneous S. aureus infection and discusses their diagnostic and therapeutic implications. Three interconnected pathophysiological pathways appear central to this susceptibility: disruption of the cutaneous barrier, nephrotic and uremic immune dysfunction, and impaired lymphatic immune surveillance. These abnormalities facilitate bacterial colonization, and invasion, while S. aureus further exploits the renal host through adhesins, toxins, biofilm formation, and immune-evasion mechanisms. The review also highlights the challenges of managing severe staphylococcal infections in patients with kidney disease and critical illness, where augmented renal clearance, expanded volume of distribution, extracorporeal renal support, and fluctuating renal function may substantially influence antimicrobial exposure. Current management requires early recognition, source control, individualized antimicrobial selection, renal-adapted dosing, therapeutic drug monitoring, and antimicrobial stewardship. Although emerging anti-virulence and immunomodulatory strategies show promise, most remain at the preclinical or early translational stage. Overall, renal edema should be regarded as a biologically active modifier of host–pathogen interactions that contributes to increased susceptibility to cutaneous S. aureus infection across the spectrum of kidney disease. Full article

Background/Objectives: Sinonasal osteomas are benign, slow-growing tumors that are typically asymptomatic and incidentally detected. However, in rare cases, they may present with atypical and potentially serious complications involving other sinonasal, orbital, or intracranial structures. This review aims to synthesize these unusual manifestations and to highlight the underlying mechanisms, diagnostic challenges, and management implications. Methods: A narrative review of the literature was conducted, focusing on reported cases of sinonasal osteomas with rare or complicated presentations. Studies were analyzed with emphasis on clinical features, imaging findings, pathophysiological mechanisms, and treatment strategies. Results: Unusual presentations of sinonasal osteomas are primarily driven by sinus obstruction, progressive expansion, and skull-base erosion. These processes may result in complications such as pneumocephalus, intracranial mucoceles, cerebrospinal fluid leaks, orbital compression, and secondary infections. Clinical manifestations are often nonspecific, including headache, seizures, visual disturbances, or focal neurological deficits, which may delay diagnosis. High-resolution computed tomography is essential for identifying the osseous lesion and associated bone changes, while magnetic resonance imaging is critical for assessing soft-tissue involvement and intracranial extension. Management is individualized, with surgical resection indicated in most symptomatic or complicated cases, using endoscopic, open, or combined approaches. Conclusions: Although rare, atypical manifestations of sinonasal osteomas can result in significant morbidity. A mechanism-based understanding, supported by appropriate imaging, is essential for accurate diagnosis and timely management. Increased clinical awareness is crucial to improving outcomes in these uncommon but clinically significant cases. Full article

Background: Congenital fibular deficiency is a rare longitudinal deficiency of the lower extremity associated with limb-length discrepancy, ankle and foot deformity, soft-tissue imbalance, and functional impairment. Reconstruction may be challenging because bone healing, regenerate maturation, and mechanical stability can be less predictable in selected patients. Case Presentation: A man with congenital fibular deficiency developed chronic distal tibial nonunion after corrective osteotomy at another institution. The nonunion persisted for four years, and the patient presented to our hospital with inability to bear weight and wheelchair dependence. A comprehensive salvage strategy was performed, including Achilles tendon lengthening using the Vulpius technique, removal of retained fixation material, debridement and refreshment of the nonunion site, negative bacteriological cultures, autologous cancellous iliac bone grafting, acute shortening and compression of the docking site, circular external fixation, proximal tibial osteotomy, and gradual lengthening. Low-intensity pulsed ultrasound was applied postoperatively as an adjunctive biological stimulus. Results: Bone union was achieved, and the external fixator was removed approximately one year after surgery. A total lengthening of 78 mm was achieved. At 12-year follow-up, the AOFAS ankle-hindfoot score was 90, ankle range of motion was 5° dorsiflexion and 40° plantarflexion, and the JOA knee score was 95. The patient walked independently without assistive devices and continued to work. Mild residual varus deformity of the proximal tibia was present, but the patient reported no knee pain, ankle pain, or ankle instability, and radiographs showed no progressive osteoarthritic changes. Conclusions: In selected patients with congenital fibular deficiency and chronic nonunion after previous treatment, durable limb salvage may be achieved using an individualized strategy that addresses both biological and mechanical factors. Full article

Crayfish with cyan soft-carapace and red hard-carapace differ considerably in market value. To investigate the causes underlying this difference in shell color, we selected 120 healthy Procambarus clarkii of similar size (9–10 cm), equally divided by shell color and sex. Muscle quality, pigment deposition, and DGAT2 mRNA expression were compared between the two shell-color types. The results showed that: (1) Muscle hardness was significantly higher in red hard-carapace crayfish than in cyan soft-carapace crayfish (p < 0.05), whereas no significant difference in muscle elasticity was observed among groups (p > 0.05). (2) A significant interaction between shell color and sex influenced crude fat and ash content (p < 0.05). Crude fat content was higher in red hard-carapace crayfish, and ash content was highest in male red hard-carapace crayfish, significantly exceeding that in male cyan soft-carapace crayfish (p < 0.05). (3) Moisture and crude protein content were not significantly affected by the interaction between shell color and sex (p > 0.05), with no notable differences across groups. (4) The contents of astaxanthin, lutein, and β-carotene in the shell were significantly influenced by the interaction between sex and shell color (p < 0.05). Astaxanthin was lowest in female cyan soft-carapace crayfish, and lutein was highest in male red hard-carapace crayfish, and β-carotene showed no significant differences. (5) DGAT2 mRNA expression was highest in hepatic tissue across all groups (p < 0.05). In gonads, expression was higher in ovaries of cyan soft-carapace crayfish and in testes of red hard-carapace crayfish (p < 0.05). (6) DGAT2 mRNA expression in the inner membrane, muscle, and intestine was significantly affected by the interaction between shell color and sex (p < 0.05), with specific expression patterns varying among tissues and groups. These findings indicate that shell color and sex interact to influence nutritional composition, carotenoid profile, and gene expression, providing insights into the mechanisms of body color formation and its physiological correlates. Full article

Introduction: Otorrhagia is an uncommon finding in forensic practice and is classically associated with skull base fractures, temporal bone trauma, or barotraumatic events. However, the literature suggests that ear bleeding may also rarely occur in deaths due to neck compression, including strangulation and hanging. Case Presentation: We report the case of a man died by hanging. External examination revealed an oblique ligature mark on the neck, conjunctival petechiae, and bilateral otorrhagia. At autopsy, no fractures of the skull vault or skull base were identified. Otoscopic examination showed bilateral tympanic membrane laceration. Internal examination of the neck disclosed small hemorrhagic infiltrates in the perithyroid muscles and prevertebral soft tissues, as well as bilateral carotid intimal tears consistent with Amussat’s sign. Moreover, a unilateral lesion involving the petrous portion of the temporal bone was observed. The distinctive feature of this case is the association of bilateral otorrhagia, bilateral tympanic membrane laceration, and unilateral petrous bone erosion in the absence of skull base fracture. Histology showed visceral congestion, pulmonary overdistension with rupture of interalveolar septa, cerebral edema, myocardial fiber fragmentation and trabecular remodeling and areas of necrosis of the bone fragment sampled from the right petrous temporal bone. Death was attributed to mechanical asphyxia due to hanging. Conclusions: This case suggests that bilateral otorrhagia in hanging may result from the combined effects of impaired cervico-cephalic venous drainage and pressure changes transmitted to the middle ear during forceful respiratory efforts. The pre-existing unilateral petrous bone lesion may have acted as a local predisposing factor, although its etiology and actual contribution cannot be established with certainty. Otoscopic examination should therefore be regarded as a potentially useful adjunct in selected cases, particularly for documenting auricular findings and supporting differential diagnosis. Full article

Viscous effects play an important role in the mechanical characterization of soft biological tissues under high-strain-rate loading. Accurate modeling of these behaviors is important for impact biomechanics, injury prediction, and crash safety analysis, in which biological tissues may experience high-strain-rate deformation. To describe the dynamic mechanical responses of soft tissues, a reliable constitutive framework is therefore needed to represent the dynamic response of soft tissues under high-strain-rate loading. The objective of this study is to develop and evaluate a viscohyperelastic constitutive framework for describing the dynamic compressive responses of multiple soft tissues. The proposed formulation is constructed within a continuum mechanics framework, in which the viscous contribution is expressed using objective invariant functions, namely $J_2$, $J_6$, and $J_7$. The developed analytical formulations are calibrated against high-strain-rate experimental data from different soft biological tissues, namely porcine meniscus, bovine liver, and ovine brain tissues. To find the material model parameters, genetic algorithm optimization is used to identify the material parameters and assess the robustness of the fitting procedure. In order to assess the robustness of the proposed constitutive framework across different loading rates, a multi-objective optimization strategy is used to calibrate the model parameters by fitting multiple strain-rate-dependent responses at the same time. This approach enables the model predictive capability to be evaluated over a range of high-strain-rate conditions. These results show that the proposed framework can reasonably describe the nonlinear and rate-dependent mechanical responses of different soft tissues under dynamic compression. Full article

Traumatic brain injury (TBI) presents a mechanically sensitive and pharmacologically complex environment in which therapeutic delivery remains challenging. Bigels may offer a formulation strategy for incorporating therapeutics with differing physicochemical properties while providing soft, viscoelastic matrices with properties that may be relevant to neural delivery applications. This study evaluated the in vitro formulation feasibility of a biphasic stearate organogel–methylcellulose/gelatin bigel as a mechanically compliant biphasic vehicle for localized delivery of neurotherapeutic agents. Bigels were fabricated by hot emulsification and genipin crosslinking to generate hydrogel-dominant dual-phase systems. Hydrogel:organogel formulations of 95:5 (BG1) and 85:15 (BG2) showed storage moduli of approximately 250 Pa and 200 Pa, respectively, and compressive Young’s moduli of 0.39 and 0.70 kPa, within reported ranges for soft brain tissue. Stress relaxation confirmed viscoelastic behaviour, while minimal oil leakage (<0.2%) indicated phase stability. BG1 showed 52% porosity, pore sizes of 1.8–22 µm, and approximately 14% weight gain. Drug release followed Weibull kinetics (R² = 0.99–0.999), with nicotinamide showing faster release and N-acetylcysteine and TPGS showing more sustained release. Both unloaded and drug-loaded bigels maintained >70% PC12 cell viability. These findings support the formulation feasibility of biphasic bigels as mechanically compliant vehicles capable of accommodating therapeutics with differing physicochemical properties and exhibiting differential release behaviour. Further studies are required to evaluate degradation, tissue interactions, retention, and therapeutic performance in advanced in vitro and in vivo models. Full article

Soybean (Glycine max) is an important model crop for studying plant functional genes, such as the NAC transcription factor (TF) gene family. The NAC transcription factor (TF) family is one of the largest plant-specific TF families and plays critical roles in plant growth, development, and stress responses. In this study, we performed a pan-genome-wide analysis of NAC genes using 29 soybean genomes. A total of 5051 NAC genes were identified and clustered into 245 orthologous gene groups (OGGs), including 58 core, 88 soft-core, 32 shell, and 67 cloud groups. Based on phylogenetic relationships, the representative NAC OGGs were assigned to 18 subfamilies, 17 of which contained soybean NAC genes. Gene duplication analysis indicated that whole-genome duplication (WGD)/segmental duplication was the predominant driver of NAC family expansion, accounting for 90.88% of duplication events. Approximately 39.30% of NAC genes carried at least one intact transposable element (TE) within 2 kb upstream or downstream regions. NAC genes with copy number variation (CNV) harbored more nearby TEs than non-CNV genes (1.54 vs. 1.31 TEs per gene), and dispensable NAC genes contained more nearby TEs than core NAC genes (1.59 vs. 1.33 TEs per gene). These results indicate a significant association between local TE abundance and NAC gene CNV or dispensability. Selection pressure analysis showed that dispensable NAC genes had higher Ka, Ks, and Ka/Ks values than core genes, suggesting relatively relaxed evolutionary constraints. Expression profiling across six tissues revealed distinct transcriptional patterns among NAC subfamilies. Structurally conserved subfamilies generally showed broader expression, whereas structurally divergent subfamilies displayed greater expression variability. Regulatory network and Gene Ontology (GO) enrichment analyses suggested that conserved subfamilies were mainly associated with stress responses, while divergent subfamilies were related to cell wall regulation, signal transduction, and ion homeostasis. Further analysis of Wm82 drought RNA-seq data prioritized several putative drought-responsive NAC candidates, including Glyma.16G043200, Glyma.06G248900, Glyma.07G050600, Glyma.12G206900, and Glyma.18G261300. Overall, these findings elucidate the mechanisms of expansion and the functional divergence of the NAC gene family at the soybean pan-genome level, providing a theoretical basis for understanding NAC gene evolution and facilitating future crop improvement. Full article

Introduction: Several Enterobacterales species harboring New Delhi metallo-β-lactamase (NDM-1) have been reported worldwide. Among them is Providencia stuartii (P. stuartii), an emerging pathogen in nosocomial infections. Objective: This study aimed to perform the clinical and genomic characterization of NDM-1-producing P. stuartii isolates recovered from hospitalized patients during the COVID-19 pandemic in Southern Brazil. Materials and Methods: A retrospective observational study was conducted between April and September 2021 at a Brazilian teaching hospital. Fifty P. stuartii isolates were identified, and carbapenem-resistant isolates underwent phenotypic and molecular characterization. Genetic relatedness was assessed by Enterobacterial Repetitive Intergenic Consensus PCR (ERIC-PCR), and selected isolates were subjected to whole-genome sequencing using the Illumina NextSeq platform to determine sequence types, resistance genes, virulence determinants, and plasmid content. Statistical analyses were performed using SPSS version 20.0. Results: Among the 50 isolates, 21 (42%) harbored the blaNDM-1 gene. Most isolates were recovered from tracheal aspirates (57.2%), followed by blood (23.8%), urine (9.5%), and skin and soft tissue samples (9.5%). Significant associations were observed between NDM-1-producing isolates and SARS-CoV-2 infection (p = 0.013), central venous catheter use (p = 0.012), mechanical ventilation (p = 0.006), hemodialysis (p = 0.033), previous antimicrobial exposure, and mortality (p = 0.021). Genomic analysis revealed the presence of blaNDM-1, blaOXA-1, and multiple resistance determinants associated with aminoglycosides, fluoroquinolones, macrolides, tetracyclines, and folate pathway inhibitors. ERIC-PCR demonstrated low genetic variability among isolates, suggesting possible clonal dissemination within the hospital environment. Conclusions: This study reports the emergence of NDM-1-producing P. stuartii during the COVID-19 pandemic in a Brazilian teaching hospital. The low genetic variability among isolates and the multidrug-resistant profile highlight the potential for nosocomial dissemination and reinforce the importance of genomic surveillance and infection control strategies. Full article

Background: Craniofacial growth is regulated by a complex interaction of genetic, functional, and systemic metabolic factors. Mechanical loading generated during mastication plays a fundamental role in mandibular development through bone modeling and remodeling mechanisms. In contrast, Type I diabetes mellitus is associated with impaired bone metabolism, which may compromise skeletal growth. Although the independent effects of functional loading and metabolic disorders on bone tissue have been widely investigated, their combined influence on mandibular development remains insufficiently understood. Objective: This study primarily aimed to evaluate the effect of Type I diabetes mellitus on mandibular growth in growing rats and, secondarily, to assess the impact of dietary consistency (hard versus soft food) on mandibular development under diabetic and non-diabetic conditions, as well as determine whether diabetes modifies the mandibular adaptive response to increased masticatory loading. Materials and Methods: An experimental animal study was conducted using twenty-four male Wistar rats aged one month. The animals were randomly allocated into four groups according to metabolic status (control or diabetic) and dietary consistency (hard or soft diet). Type I diabetes mellitus was experimentally induced in the relevant groups using streptozotocin. All animals underwent cone beam computed tomography (CBCT) scanning at baseline (Day 1) and at the end of the experimental period (Day 28). Linear measurements were obtained using specialized software following euthanasia. Two-way ANOVA was used to evaluate the effects of diabetes, diet, and their interaction, using appropriate post hoc tests for multiple comparisons. Categorical variables were analyzed using the chi-square test. A p-value < 0.05 was considered statistically significant. Results: Longitudinal morphometric analysis demonstrated that Type I diabetes mellitus significantly impaired mandibular growth. Diabetic animals exhibited reduced growth rates and smaller final mandibular dimensions compared with controls. Hard diet intake significantly enhanced mandibular development in control animals, reflecting a strong adaptive response to increased functional loading. However, this osteogenic response was markedly attenuated in diabetic rats. Under soft-diet conditions, differences between control and diabetic groups were diminished, indicating that reduced mechanical stimulation limits adaptive growth responses. Significant interaction effects between diabetes and dietary consistency were observed in several morphometric parameters, particularly those related to mandibular body length, ramus height, and condylar position. Conclusions: Type I diabetes mellitus exerts a detrimental effect on mandibular growth in growing rats and compromises the adaptive response of craniofacial structures to mechanical loading. Although a hard diet functions as a potent osteogenic stimulus, its growth-promoting effect is substantially reduced in the presence of metabolic dysfunction. Full article

Self-healing biomaterials have attracted significant attention due to their ability to restore structural integrity, extend material lifetime, and reduce maintenance costs without external intervention. In this study, Polyvinyl Alcohol/Graphene Oxide/Eggshell Particle (PVA/GO/ESP) composite hydrogels were synthesized via a freeze–thawing method and characterized using XRD, SEM/EDS, and FTIR analyses. The effect of ESP incorporation on the self-healing and mechanical properties of the hydrogels was systematically investigated. Tensile test results demonstrated that incorporation of 1 wt% ESP improved the tensile strength up to 0.326 MPa while maintaining high strain capacity. Healing efficiency values calculated from recovered tensile strength showed approximately 69%, 47%, and 67% recovery for PVA/GO, PVA/GO/ESP (0.5%), and PVA/GO/ESP (1%) hydrogels, respectively. The developed hydrogels demonstrated rapid self-healing behavior at room temperature without external stimuli. These findings suggest that ESP-reinforced PVA/GO hydrogels may serve as promising candidates for future biomaterial and soft tissue engineering studies. The developed hydrogels demonstrated enhanced tensile strength, rapid self-healing behavior, and promising swelling properties, indicating their potential use in soft tissue engineering and biomaterial applications. Full article

The vitreous body is not only a transparent filling material of the posterior segment; it is a soft, hydrated, and biologically active matrix that supports structural, optical, and biochemical homeostasis. Vitrectomy therefore leaves a functional deficit that current substitutes only partly address. Intraocular gases, silicone oils, and perfluorocarbon liquids remain essential surgical tools, but they mainly provide mechanical tamponade and do not reproduce native viscoelasticity, diffusion control, or protection against oxidative and inflammatory stress. This review considers vitreous replacement as a functional biomaterials challenge. We discuss native vitreous physiology, the limitations of present tamponade agents, and emerging bioengineered substitutes designed to create a more physiological intravitreal environment. Particular attention is given to hydrogel and polymer-based systems, especially hyaluronic acid-based and in situ crosslinked platforms, which are being developed to combine optical clarity, injectability, soft mechanical support, controlled degradation, and favorable tissue interaction. We also emphasize the need for standardized preclinical testing of swelling, enzymatic stability, drug diffusion, rheology, and long-term biocompatibility. Although next-generation materials may move the field beyond passive space filling, manufacturing reproducibility, regulatory validation, chronic safety, and cautious early-phase trials remain major translational barriers. Full article

Background: Severe jaw atrophy (Cawood and Howell Class V–VI) often renders conventional endosseous implantation unfeasible due to the lack of medullary bone and vascularization. This study presents a digital workflow for customized subperiosteal implants designed to eliminate bone segmentation errors and ensure optimal passive fit. Methods: Two clinical cases of severe atrophy—a full-arch maxillary rehabilitation and a unilateral partial rehabilitation—were treated using a prosthetic-driven CAD/CAM workflow. Key innovations included densitometric mapping using Hounsfield Units (HU) to identify high-mineralization zones (+1200 to +1800 HU) for strategic screw fixation. Intraoperatively, cobalt–chrome osteoplasty guides and PMMA check-templates were utilized to validate bone segmentation accuracy in vivo and regularize the cortical base. Results: The protocol achieved high precision with a monitored alignment deviation of 0.2 mm. At the 2-year follow-up, clinical and radiographic evaluations (CBCT) confirmed the total absence of gaps at the bone–implant interface. No signs of peri-implantitis, osteolysis, or progressive bone loss were observed, and soft tissues remained stable and healthy. Discussion: Success was driven by the rigorous management of the bone–implant interface and the use of preparatory surgical devices to bridge the gap between digital planning and surgical reality. The mechanical stability achieved through divergent fixation vectors prevented stress shielding by converting shear forces into compression, stimulating basal bone density according to Wolff’s Law. Conclusions: The standardized digital workflow and the use of preparatory surgical devices in this preliminary study showed that complex rehabilitations can be performed with favorable short-term outcomes. While this approach reduces surgical time and biological stress, further prospective studies are required to confirm its clinical predictability and define next-generation subperiosteal implants as a valid alternative for the management of severely atrophic cases. Full article

Scaffolds designed for mechanically demanding soft tissue engineering applications should integrate mechanical support, efficient mass transfer, and good cellular compatibility. This work presents a one-pot method based on “radical-free click chemistry + carbodiimide coupling” to produce a double-network (DN) PEG–alginate cryogel. The PEG network is formed by a Michael addition reaction between thiol-based crosslinker and 8-arm PEG-acrylate. The second network is covalently crosslinked through EDC/NHS-mediated coupling of carboxyl groups in alginate and adipic acid dihydrazide (AAD). The subsequent freezing and gelation of the gel precursor at sub-zero temperatures results in an ice templated cryogel with an interconnected macroporous network. These cryogels demonstrate high elasticity, compressive modulus and rapid swelling equilibrium in aqueous environments, as well as controlled degradation under physiological conditions. Compared to the classical Ca²⁺ ion crosslinking systems, the covalent linking of the alginate in the double-network cryogel shows advantages in mechanical and structural stability. In addition, it is cell-compatible and allows culture of mesenchymal stem cells (MSCs) with homogeneous infiltration. Furthermore, the double-network cryogels supports chondrogenic differentiation of MSCs upon treatment with chondrogenic media or macrophage-conditioned media for a short period of time. These results indicate that crosslinking chemistry and polymer composition can be used to modulate the balance between mechanical performance and degradation behavior, while maintaining cytocompatibility and an interconnected macroporous network, thereby providing a scaffold design strategy for applications that require coordinated mechanical support and mass transfer, such as cartilage-related tissue engineering. Full article

Background: Modern warfare has introduced novel mechanisms of injury, particularly drone-induced blast trauma, resulting in complex craniomaxillofacial injuries. These injuries differ substantially from typical ballistic wounds and require adapted surgical strategies. This study was conducted to evaluate the clinical characteristics, management approaches, and long-term outcomes of midfacial blast injuries. Methods: A retrospective analytical study was conducted on 41 patients with drone-induced midfacial blast injuries treated at a tertiary referral center in Armenia following the 2020 Nagorno-Karabakh War. All patients underwent surgical management after initial stabilization and were followed for 5 years. Clinical outcomes, complications, and reconstructive needs were assessed. Results: All patients presented with comminuted midfacial fractures, which were frequently associated with polytrauma (87.8%). Burns were observed in 82.9% of cases. Surgical management included radical debridement and early definitive osteosynthesis using titanium fixation systems. No cases of postoperative osteomyelitis, bone sequestration, or implant failure were observed during the 5-year follow-up period. Patients with extensive soft tissue defects, particularly nasal and lip amputations, required multiple reconstructive procedures. Long-term follow-up revealed progressive soft tissue thinning over titanium meshes, especially in the zygomatico-orbital region, necessitating secondary interventions such as lipofilling. Conclusions: Drone-induced midfacial blast injuries represent a distinct and severe form of trauma. Early definitive reconstruction following adequate debridement was associated with favorable outcomes. However, soft tissue reconstruction remains challenging and often requires staged procedures. Long-term follow-up is essential to manage delayed complications and optimize aesthetic outcomes. Full article