BACKGROUND: Hemorrhagic shock is well documented as a leading cause of preventable fatalities among military casualties. During military operations plasma can be transfused while waiting for whole blood. This study was conducted to assess the safety and efficacy of two new freeze-dried plasma formulations in a porcine model of traumatic hemorrhagic shock.
METHODS: In the face of species-specific transfusion, transfusible blood products were derived from porcine sources. The efficacy of three lyophilized plasma (LP) formulations was evaluated: lyophilized plasma (LP), concentrated lyophilized plasma (CLP), and platelet-rich concentrated lyophilized plasma (PCLP). Pigs were subjected to multi-trauma and hemorrhagic shock. Ninety minutes post-shock induction, the animals were treated with one of the three lyophilized products. Monitoring included systolic blood pressure and cardiac output. Point-of-care and laboratory diagnostic tests were used to assess renal function, real-time hemostasis (ROTEM), and coagulation. Histological examinations of kidney, lung, and muscle tissues were conducted 4 h after shock induction.
RESULTS: CLP and PCLP significantly improved systolic blood pressure and cardiac output and positively influenced base excess, creatinine, various ROTEM, and coagulation markers compared with standard LP without histologic modification. No adverse effect was associated with the transfusion of any of the plasma products throughout the experimental procedures.
CONCLUSIONS: Both CLP and PCLP exhibit promising therapeutic potential for managing hemorrhagic shock in scenario where whole blood supplies are limited. However, the distinct physiological and coagulation characteristics of the swine model necessitate further investigation using humanized preclinical models to fully understand their clinical applicability and constraints.

Introduction: Wound therapies are capable of modulating the complex molecular signaling profile of tissue regeneration. However traditional, bulk tissue analysis results in nonspecific expressional profiles and diluted signaling that lacks temporal-spatial information. Methods: An acute incisional porcine wound model was developed in the context of negative pressure wound therapy (NPWT). Dressing materials were inserted into wounds with or without NPWT exposure and evaluated over 8-hours. Upon wound explantation, tissue was stratified and dissected into the epidermis, dermis, or subcutaneous layer, or left undissected as a bulk sample and all groups processed for RNAseq. RNAseq of stratified layers provided spatial localization of expressional changes within defined tissue regions, including angiogenesis, inflammation, and matrix remodeling. Results: Different expressional profiles were observed between individual tissue layers relative to each other within a single wound group and between each individual layer relative to bulk analysis. Tissue stratification identified unique differentially expressed genes within specific layers of tissue that were hidden during bulk analysis, as well as amplification of weak signals and/or inversion of signaling between two layers of the same wound, suggesting that two layers of skin can cancel out signaling within bulk analytical approaches. Discussion: The unique wound stratification and spatial RNAseq approach in this study provides a new methodology to observe expressional patterns more precisely within tissue that may have otherwise not been detectable. Together these experimental data offer novel insight into early expressional patterns and genomic profiles, within and between tissue layers, in wound healing pathways that could potentially help guide clinical decisions and improve wound outcomes.

Accurate intraoperative assessment of organ perfusion is a pivotal determinant in preserving organ function e.g. during kidney surgery including partial nephrectomy or kidney transplantation. Hyperspectral imaging (HSI) has great potential to objectively describe and quantify this perfusion as opposed to conventional surrogate techniques such as ultrasound flowmeter, indocyanine green or the subjective eye of the surgeon. An established live porcine model under general anesthesia received median laparotomy and renal mobilization. Different scenarios that were measured using HSI were (1) complete, (2) gradual and (3) partial malperfusion. The differences in spectral reflectance as well as HSI oxygenation (StO2) between different perfusion states were compelling and as high as 56.9% with 70.3% (± 11.0%) for \"physiological\" vs. 13.4% (± 3.1%) for \"venous congestion\". A machine learning (ML) algorithm was able to distinguish between these perfusion states with a balanced prediction accuracy of 97.8%. Data from this porcine study including 1300 recordings across 57 individuals was compared to a human dataset of 104 recordings across 17 individuals suggesting clinical transferability. Therefore, HSI is a highly promising tool for intraoperative microvascular evaluation of perfusion states with great advantages over existing surrogate techniques. Clinical trials are required to prove patient benefit.

Wound healing is a complex process that is still not fully understood despite extensive research. To address this, we aimed to design and characterize a standardized porcine model for the evaluation of wound healing, dressings, cell therapies, and pharmaceutical agents. Using a standardized approach, we examined the wound healing process in 1.2 mm-deep dermatome wounds at defined positions in 11 female pigs. Unlike previous studies that have only described/analyzed selected punch biopsies, we performed and described histological analyses along the complete wound length using quantitative morphometric methods. All animals remained fully healthy following surgery and showed no signs of infection. Our histopathological evaluation using a predetermined grading score and quantitative manual morphometry demonstrated the impact of different tissue sampling methods, sampling sites, and residual dermis thickness on wound healing. Our study presents a reproducible model for wound healing evaluation and demonstrates the usefulness of porcine models for assessing dermal and epidermal wound healing. The use of histological analyses over the complete wound length provides advantages over previous studies, leading to the possibility of a deeper understanding of the wound healing process. This model could potentially facilitate future research on novel wound dressings and local wound healing therapies.

Traumatic brain injury (TBI), a significant global health issue, is affecting ∼69 million annually. To better understand TBI\'s impact on brain function and assess the efficacy of treatments, this study uses a novel temporal-spatial cross-group approach with a porcine model, integrating resting-state functional magnetic resonance imaging (rs-fMRI) for temporal and arterial spin labeling for spatial information. Our research used 18 four-week-old pigs divided into three groups: TBI treated with saline (SLN, n = 6), TBI treated with fecal microbial transplant (FMT, n = 6), and a sham group (sham, n = 6) with only craniectomy surgery as the baseline. By applying machine learning techniques-specifically, independent component analysis and sparse dictionary learning-across seven identified resting-state networks, we assessed the temporal and spatial correlations indicative of treatment efficacy. Both temporal and spatial analyses revealed a consistent increase of correlation between the FMT and sham groups in the executive control and salience networks. Our results are further evidenced by a simulation study designed to mimic the progression of TBI severity through the introduction of variable Gaussian noise to an independent rs-fMRI dataset. The results demonstrate a decreasing temporal correlation between the sham and TBI groups with increasing injury severity, consistent with the experimental results. This study underscores the effectiveness of the methodology in evaluating post-TBI treatments such as the FMT. By presenting comprehensive experimental and simulated data, our research contributes significantly to the field and opens new paths for future investigations into TBI treatment evaluations.

Background/Objectives: Cadaveric models have traditionally been a mainstay of dental and medical education worldwide since their inception. In Australia, educators at dental schools were among the first to use cadaveric porcine heads in formal teaching in oral surgery. This practice has since fallen out of favour in most modern dental curricula. The aim of this pilot study was to determine the utility of cadaveric porcine models for oral surgery training from a student perspective (Griffith University, Gold Coast, Australia). Methods: Thirty participants who were all third-year dental students attended a two-hour session comprising a 30 min lecture followed by a 90 min practical workshop. The lecture outlined the steps and supervision of students during the practical and was provided by a consultant maxillofacial surgeon. At the conclusion of the workshop, participants were asked to anonymously complete a printed questionnaire with eight questions related to their experience. Results: Prior to the workshop, two-thirds (61%) of participants felt that they had been taught the surgical procedure for raising mucoperiosteal flaps adequately in their dental school curriculum during their third year, although only 43% of students had assisted specialty residents in raising a mucoperiosteal flap and 14% reported having performed the procedure themselves. Almost all students (96%) agreed that the porcine model was useful for their dental education and that they would practice the exercise using the model again if provided with the opportunity. The questionnaire had a 93.33% completion rate. Conclusions: This pilot study indicates that porcine heads present a useful, low-cost adjunct in the learning of basic oral surgical procedures.

UNASSIGNED: The standard treatment for preventing rejection in vascularized composite allotransplantation (VCA) currently relies on systemic immunosuppression, which exposes the host to well-known side effects. Locally administered immunosuppression strategies have shown promising results to bypass this hurdle. Nevertheless, their progress has been slow, partially attributed to a limited understanding of the essential mechanisms underlying graft rejection. Recent discoveries highlight the crucial involvement of innate immune components, such as neutrophil extracellular traps (NETs), in organ transplantation. Here we aimed to prolong graft survival through a tacrolimus-based drug delivery system and to understand the role of NETs in VCA graft rejection.
UNASSIGNED: To prevent off-target toxicity and promote graft survival, we tested a locally administered tacrolimus-loaded on-demand drug delivery system (TGMS-TAC) in a multiple MHC-mismatched porcine VCA model. Off-target toxicity was assessed in tissue and blood. Graft rejection was evaluated macroscopically while the complement system, T cells, neutrophils and NETs were analyzed in graft tissues by immunofluorescence and/or western blot. Plasmatic levels of inflammatory cytokines were measured using a Luminex magnetic-bead porcine panel, and NETs were measured in plasma and tissue using DNA-MPO ELISA. Lastly, to evaluate the effect of tacrolimus on NET formation, NETs were induced in-vitro in porcine and human peripheral neutrophils following incubation with tacrolimus.
UNASSIGNED: Repeated intra-graft administrations of TGMS-TAC minimized systemic toxicity and prolonged graft survival. Nevertheless, signs of rejection were observed at endpoint. Systemically, there were no increases in cytokine levels, complement anaphylatoxins, T-cell subpopulations, or neutrophils during rejection. Yet, tissue analysis showed local infiltration of T cells and neutrophils, together with neutrophil extracellular traps (NETs) in rejected grafts. Interestingly, intra-graft administration of tacrolimus contributed to a reduction in both T-cellular infiltration and NETs. In fact, in-vitro NETosis assessment showed a 62-84% reduction in NETs after stimulated neutrophils were treated with tacrolimus.
UNASSIGNED: Our data indicate that the proposed local delivery of immunosuppression avoids off-target toxicity while prolonging graft survival in a multiple MHC-mismatch VCA model. Furthermore, NETs are found to play a role in graft rejection and could therefore be a potential innovative therapeutic target.

BACKGROUND: Significant research has been devoted to developing noninvasive approaches to neuromonitoring. Clinical validation of such approaches is often limited, with minimal data available in the clinically relevant elevated ICP range.
METHODS: To allow ultrasound-guided placement of an intraventricular catheter and to perform simultaneous long-duration ICP and ultrasound recordings of cerebral blood flow, we developed a large unilateral craniectomy in a swine model. We also used a microprocessor-controlled actuator for intraventricular saline infusion to reliably and reversibly manipulate ICP according to pre-determined profiles.
RESULTS: The model was reproducible, resulting in over 80 hours of high-fidelity, multi-parameter physiological waveform recordings in twelve animals, with ICP ranging from 2 to 78 mmHg. ICP elevations were reversible and reproducible according to two predetermined profiles: a stepwise elevation up to an ICP of 30-35 mmHg and return to normotension, and a clinically significant plateau wave. Finally, ICP was elevated to extreme levels of greater than 60 mmHg, simulating extreme clinical emergency.
METHODS: Existing methods for ICP monitoring in large animals typically relied on burr-hole approaches for catheter placement. Accurate catheter placement can be difficult in pigs, given the thickness of their skull. Additionally, ultrasound is significantly attenuated by the skull. The open cranium model overcomes these limitations.
CONCLUSIONS: The hemicraniectomy model allowed for verified placement of the intraventricular catheter, and reversible and reliable ICP manipulation over a wide range. The large dural window additionally allowed for long-duration recording of cerebral blood flow velocity from the middle cerebral artery.

BACKGROUND: Implementing a robotic system for minimally invasive surgical procedures necessitates a comprehensive training regimen. This involves not only mastering the technological aspects of the robotic system but also enhancing surgical proficiency in manipulating robotic instruments. Furthermore, procedural expertise in specific surgeries is critical. Minimally invasive inguinal hernia repair is particularly suitable as an initial procedure for human application. The development of a comprehensive training model for this type of repair is a crucial element of such an educational pathway.
METHODS: Anatomical dissections were carried out on pigs to assess both the similarities and differences between pig and human anatomy. A structured minimally invasive inguinal hernia repair was performed to determine the suitability of the porcine inguinal region for training purposes.
RESULTS: A detailed anatomical description of the porcine inguinal region is outlined, to provide a framework for assessing the critical view of the porcine myopectineal orifice. By integrating the human \'ten golden rules\' for safe and effective minimally invasive inguinal hernia repair, the standardized porcine integrated robotic inguinal hernia training (SPIRIT) model describes a step-by-step approach to practice surgical techniques in a realistic setting.
CONCLUSIONS: The SPIRIT model is designed to be a well-structured training model for minimally invasive inguinal hernia repair and incorporates the specific surgical steps as encountered in a human patient.

BACKGROUND: The purpose of this study was to investigate a therapeutic approach targeting the inflammatory response and consequent remodeling from ischemic myocardial injury.
RESULTS: Coronary thrombus aspirates were collected from patients at the time of ST-segment-elevation myocardial infarction and subjected to array-based proteome analysis. Clinically indistinguishable at myocardial infarction (MI), patients were stratified into vulnerable and resilient on the basis of 1-year left ventricular ejection fraction and death. Network analysis from coronary aspirates revealed prioritization of tumor necrosis factor-α signaling in patients with worse clinical outcomes. Infliximab, a tumor necrosis factor-α inhibitor, was infused intravenously at reperfusion in a porcine MI model to assess whether infliximab-mediated immune modulation impacts post-MI injury. At 3 days after MI (n=7), infliximab infusion increased proregenerative M2 macrophages in the myocardial border zone as quantified by immunofluorescence (24.1%±23.3% in infliximab versus 9.29%±8.7% in sham; P<0.01). Concomitantly, immunoassays of coronary sinus samples quantified lower troponin I levels (41.72±7.34 pg/mL versus 58.11±10.75 pg/mL; P<0.05) and secreted protein analysis revealed upregulation of injury-modifying interleukin-2, -4, -10, -12, and -18 cytokines in the infliximab-treated cohort. At 4 weeks (n=12), infliximab treatment resulted in significant protective influence, improving left ventricular ejection fraction (53.9%±5.4% versus 36.2%±5.3%; P<0.001) and reducing scar size (8.31%±10.9% versus 17.41%±12.5%; P<0.05).
CONCLUSIONS: Profiling of coronary thrombus aspirates in patients with ST-segment-elevation MI revealed highest association for tumor necrosis factor-α in injury risk. Infliximab-mediated immune modulation offers an actionable pathway to alter MI-induced inflammatory response, preserving contractility and limiting adverse structural remodeling.