Early Identification of Acute Lung Injury in a Porcine Model of Hemorrhagic Shock

Omega-3 polyunsaturated fatty acids alleviates lung injury mediated by post-hemorrhagic shock mesenteric lymph

Severe hemorrhage-induced acute lung injury (ALI) remains the major contributor to critical patient mortality and is associated with posthemorrhagic shock mesenteric lymph (PHSML) return. Omega-3 polyunsaturated fatty acids (ω-3 PUFAs) play overall protection on acute hemorrhage, but a reliable mechanism needs to be identified. The aims of this study were to investigate the role of ω-3 PUFAs in alleviating ALI and whether is related to the endotoxin contained in PHSML. Mesenteric lymph was harvested from rats subjected to hemorrhagic shock (hemorrhage-induced hypotension of 40 ± 2 mmHg for 90 min plus by resuscitation) or sham shock. The effect of ω-3 PUFAs on pulmonary function, water content, morphology, and LBP, CD14, TNF-α, and IL-6 levels were observed in rats subjected to hemorrhagic shock, while the effect of PHSML intravenous infusion on the beneficial effect of ω-3 PUFAs also was investigated. In addition, the effect of ω-3 PUFAs on the endotoxin contents in mesenteric lymph were detected. Hemorrhagic shock-induced ALI was characterized by increased functional residual capacity (FRC), lung resistance (RI), inspiratory capacity (IC), respiratory frequency, water contents and structural damage, along with increases in LBP, IL-6, and TNF-α. ω-3 PUFAs treatment reduced FRC, RI, IC, frequency, water contents, LBP, IL-6, TNF-α, and alleviated morphological damage. In contrast, PHSML infusion abolished the advantageous effects of ω-3 PUFAs on the above indices and CD14. Furthermore, the endotoxin level of PHSML was significantly enhanced, but declined following ω-3 PUFAs administration. These findings together suggested that treatment with ω-3 PUFAs ameliorates hemorrhagic shock-induced ALI, which is associated with reduced endotoxin contained in PHSML.

A Bio-Inorganic Hybrid Hemostatic Gauze for Effective Control of Fatal Emergency Hemorrhage in "Platinum Ten Minutes"

Death from massive hemorrhage represents a global problem. It is a challenging task to design hemostatic materials with significant efficacy, good biocompatibility, reliable safety, and high stability. In this study, we demonstrate an effective bio-inorganic hybrid hemostat fabricated by stepwise procedures of on-site growth of zeolite gauze and immobilization of trypsin on the zeolite gauze. The as-synthesized hybrid hemostat catalyzes the transition of prothrombin-to-thrombin and exhibits excellent procoagulant performance in the both normal plasma and FX-deficient plasma. The hemostatic treatment of junctional femoral artery rupture in the porcine model confirms that this hybrid hemostat manifests itself with superior hemostatic performance over commercial hemostatic dressings, in terms of a reduced time to hemostasis and blood loss. The stability of the hybrid hemostat is validated through high temperature and violent shaking evaluation. This bio-inorganic hybrid hemostat displays high procoagulant activity, low cytotoxicity, and extended shelf life which may achieve the "Platinum Ten Minutes" rescue in battlefield and traffic accident medicine.

Video laryngoscope-guided urethral catheterization in female minipigs

OBJECTIVE

The objective of this work was to anatomically locate the urethral orifice in female minipigs and describe the use of video laryngoscopes in urethral catheterization.

METHODS

Urethral catheterization guided by a video laryngoscope was attempted in 16 adult female Bama minipigs. The anatomical location of urethral orifices, operating time and complications (mucosal edema and bleeding in the vaginal vestibule, and the numbers of red blood cells (RBCs) and white blood cells (WBCs) in mid-stream urine samples) were recorded.

RESULTS

The anatomical location of the urethral orifice: the depth of the urethral orifice in female Bama minipigs was 4.2 ± 1.2 cm; all the urethral orifices were covered by mucosal folds of the vaginal vestibule. In the supine position, the orifice of the urethra at 9-12 and 1-3 o'clock accounted for 6.25%, 6.25%, 18.75%, 50%, 12.5%, 6.25% and 6.25%, respectively. All animals were successfully catheterized and the operating time was 9.0 (6.0-12.8) min. Complications: no bleeding in the vaginal vestibule was observed; the incidence of mucosal edema was 12.5%, all of which were mild; of urine samples collected 1 h after catheterization, 12.5% were found to contain RBCs and no RBCs were detected 6 h after catheterization; no WBCs were detected 1 h or 6 h after catheterization.

CONCLUSIONS

The urethral orifice of female minipigs was located deep in the vagina at variable clock directions and was unexceptionally covered by mucosal folds. Applying a video laryngoscope in urethral catheterization allowed quick and accurate exposure of the urethral orifice and minimal operational injury in female minipigs.

The pig as a medical model for acquired respiratory diseases and dysfunctions: An immunological perspective

By definition no model is perfect, and this also holds for biology and health sciences. In medicine, murine models are, and will be indispensable for long, thanks to their reasonable cost and huge choice of transgenic strains and molecular tools. On the other side, non-human primates remain the best animal models although their use is limited because of financial and obvious ethical reasons. In the field of respiratory diseases, specific clinical models such as sheep and cotton rat for bronchiolitis, or ferret and Syrian hamster for influenza and Covid-19, have been successfully developed, however, in these species, the toolbox for biological analysis remains scarce. In this view the porcine medical model is appearing as the third, intermediate, choice, between murine and primate. Herein we would like to present the pros and cons of pig as a model for acquired respiratory conditions, through an immunological point of view. Indeed, important progresses have been made in pig immunology during the last decade that allowed the precise description of immune molecules and cell phenotypes and functions. These progresses might allow the use of pig as clinical model of human respiratory diseases but also as a species of interest to perform basic research explorations.