Current Approaches to Wound Repair in Burns: How far Have we Come From Cover to Close? A Narrative Review.

Burn injuries are a significant global health concern, with more than 11 million people requiring medical intervention each year and approximately 180,000 deaths annually. Despite progress in health and social care, burn injuries continue to result in socioeconomic burdens for victims and their families. The management of severe burn injuries involves preventing and treating burn shock and promoting skin repair through a two-step procedure of covering and closing the wound. Currently, split-thickness/full-thickness skin autografts are the gold standard for permanent skin substitution. However, deep burns treated with split-thickness skin autografts may contract, leading to functional and appearance issues. Conversely, defects treated with full-thickness skin autografts often result in more satisfactory function and appearance. The development of tissue-engineered dermal templates has further expanded the scope of wound repair, providing scar reductive and regenerative properties that have extended their use to reconstructive surgical interventions. Although their interactions with the wound microenvironment are not fully understood, these templates have shown potential in local infection control. This narrative review discusses the current state of wound repair in burn injuries, focusing on the progress made from wound cover to wound closure and local infection control. Advancements in technology and therapies hold promise for improving the outcomes for burn injury patients. Understanding the underlying mechanisms of wound repair and tissue regeneration may provide new insights for developing more effective treatments in the future.

The Lectin Pathway of the Complement System-Activation, Regulation, Disease Connections and Interplay with Other (Proteolytic) Systems.

The complement system is the other major proteolytic cascade in the blood of vertebrates besides the coagulation-fibrinolytic system. Among the three main activation routes of complement, the lectin pathway (LP) has been discovered the latest, and it is still the subject of intense research. Mannose-binding lectin (MBL), other collectins, and ficolins are collectively termed as the pattern recognition molecules (PRMs) of the LP, and they are responsible for targeting LP activation to molecular patterns, e.g., on bacteria. MBL-associated serine proteases (MASPs) are the effectors, while MBL-associated proteins (MAps) have regulatory functions. Two serine protease components, MASP-1 and MASP-2, trigger the LP activation, while the third component, MASP-3, is involved in the function of the alternative pathway (AP) of complement. Besides their functions within the complement system, certain LP components have secondary ("moonlighting") functions, e.g., in embryonic development. They also contribute to blood coagulation, and some might have tumor suppressing roles. Uncontrolled complement activation can contribute to the progression of many diseases (e.g., stroke, kidney diseases, thrombotic complications, and COVID-19). In most cases, the lectin pathway has also been implicated. In this review, we summarize the history of the lectin pathway, introduce their components, describe its activation and regulation, its roles within the complement cascade, its connections to blood coagulation, and its direct cellular effects. Special emphasis is placed on disease connections and the non-canonical functions of LP components.

Complement MASP-1 Modifies Endothelial Wound Healing.

Endothelial wound-healing processes are fundamental for the maintenance and restoration of the circulatory system and are greatly affected by the factors present in the blood. We have previously shown that the complement protein mannan-binding lectin-associated serine protease-1 (MASP-1) induces the proinflammatory activation of endothelial cells and is able to cooperate with other proinflammatory activators. Our aim was to investigate the combined effect of mechanical wounding and MASP-1 on endothelial cells. Transcriptomic analysis showed that MASP-1 alters the expression of wound-healing-related and angiogenesis-related genes. Both wounding and MASP-1 induced Ca2+ mobilization when applied individually. However, MASP-1-induced Ca2+ mobilization was inhibited when the treatment was preceded by wounding. Mechanical wounding promoted CREB phosphorylation, and the presence of MASP-1 enhanced this effect. Wounding induced ICAM-1 and VCAM-1 expression on endothelial cells, and MASP-1 pretreatment further increased VCAM-1 levels. MASP-1 played a role in the subsequent stages of angiogenesis, facilitating the breakdown of the endothelial capillary network on Matrigel®. Our findings extend our general understanding of endothelial wound healing and highlight the importance of complement MASP-1 activation in wound-healing processes.

SARS-CoV-2 Nucleocapsid Protein Is Not Responsible for Over-Activation of Complement Lectin Pathway.

The nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a viral structural protein that is abundant in the circulation of infected individuals. Previous published studies reported controversial data about the role of the N protein in the activation of the complement system. It was suggested that the N protein directly interacts with mannose-binding lectin-associated serine protease-2 (MASP-2) and stimulates lectin pathway overactivation/activity. In order to check these data and to reveal the mechanism of activation, we examined the effect of the N protein on lectin pathway activation. We found that the N protein does not bind to MASP-2 and MASP-1 and it does not stimulate lectin pathway activity in normal human serum. Furthermore, the N protein does not facilitate the activation of zymogen MASP-2, which is MASP-1 dependent. Moreover, the N protein does not boost the enzymatic activity of MASP-2 either on synthetic or on protein substrates. In some of our experiments, we observed that MASP-2 digests the N protein. However, it is questionable, whether this activity is biologically relevant. Although surface-bound N protein did not activate the lectin pathway, it did trigger the alternative pathway in 10% human serum. Additionally, we detected some classical pathway activation by the N protein. Nevertheless, we demonstrated that this activation was induced by the bound nucleic acid, rather than by the N protein itself.

Five-year prognosis of patients with acute myocardial infarction and out-of-hospital cardiac arrest.

OBJECTIVES: This study aimed to assess the mortality and prognosis of acute myocardial infarction (AMI) patients with out-of-hospital cardiac arrest (OHCA) initially admitted to Department of Anesthesiology and Intensive Care in comparison with patients initially admitted to Cardiac Centre (CC). BACKGROUND: Global acute coronary syndrome (ACS) registries often omit patients with OHCA initially admitted to anaesthesiology and intensive care units. This exclusion may lead to underestimated mortality rates in patients following acute MI worldwide. METHODS: A retrospective analysis was conducted in patients admitted in 2014 to the (Department of Anesthesiology and Intensive Care) at a single center, J.A. Reiman Teaching Hospital in Presov, Slovakia. Survival rates were evaluated in-hospital, at 30 days, and annually over a five-year period. Patients with STEMI and NSTEMI were analyzed separately, particularly during the early in-hospital phase. RESULTS: In the OHCA group, 52% of STEMI patients experienced in-hospital mortality, whereas the CC group reported only 3% mortality. The total hospital mortality for STEMI patients was 6.69%. Among NSTEMI patients in the OHCA group, in-hospital mortality reached 50%, compared to 4.33% in the CC group. The total center mortality for all NSTEMI patients was 6.09%. CONCLUSION: Although the short-term prognosis for MI patients with OHCA is unfavorable, with a 30-day mortality rate of 54.9%, for those who survive the initial 30 days following cardiac arrest and are successfully discharged from the hospital, the long-term prognosis aligns with MI patients without OHCA. In light of these findings, the inclusion of all patients with MI (from both OHCA and CC groups) in global ACS registries could significantly raise in-hospital and 30-day mortality rates (Tab. 3, Fig. 4, Ref. 21).

Absorption and pharmacokinetics of bupivacaine after bilateral topical administration in tonsillar fossae for posttonsillectomy pain relief.

No previous studies have investigated the systemic absorption of bupivacaine when used topically for posttonsillectomy pain. The present study was undertaken to investigate the pharmacokinetics of bupivacaine after administration by a swab in the tonsillar fossae over 4 min after tonsillectomy. Eleven adult patients undergoing elective tonsillectomy were recruited. After removal of both tonsils, each of the two tonsillar fossae was covered with a swab moistened with 2 mL of bupivacaine 5 mg/mL, that is, a total of 20 mg bupivacaine. Blood samples were drawn after 0, 5, 10, 20, 30, 45, and 60 min. Bupivacaine was analyzed with an ultra-high-performance liquid chromatography-tandem mass spectrometry method. The highest single measured bupivacaine serum concentration was 23.2 ng/mL and took place 10 min after drug administration. Mean (±SD) Cmax was 11.4 ± 6.0 ng/mL and mean tmax was 11.3 ± 4.7 min. Mean t1/2 was 31.6 ± 9.3 min. As the toxic concentration threshold has been reported to be in the interval 1500-4500 ng/mL, the concentrations measured were well below 2% of the lowest cited toxic threshold. In conclusion, this study shows that applying 4 mL of bupivacaine 5 mg/mL by a swab in the tonsillar fossae posttonsillectomy yields very low plasma concentrations, suggesting its safe application without any risk of systemic toxic effects.

Detrimental interactions of hypoxia and complement MASP-1 in endothelial cells as a model for atherosclerosis-related diseases.

Both hypoxia and the complement lectin pathway (CLP) are involved in atherosclerosis and atherosclerosis-related stroke and acute myocardial infarction (AMI). We have previously shown that mannose-binding lectin-associated serine protease-1 (MASP-1), the most abundant enzyme of CLP, induces an inflammatory phenotype of endothelial cells (ECs) by cleaving protease activated receptors (PARs). In the absence of data, we aimed to investigate whether hypoxia and MASP-1 interact at the level of ECs, to better understand their role in atherosclerosis-related diseases. Hypoxia attenuated the wound healing ability of ECs, increased ICAM-1 and decreased ICAM-2 expression and upregulated PAR2 gene expression. Hypoxia and MASP-1 increased GROα and IL-8 production, and endothelial permeability without potentiating each other's effects, whereas they cooperatively disrupted vascular network integrity, activated the Ca2+, CREB and NFκB signaling pathways, and upregulated the expression of E-selectin, a crucial adhesion molecule in neutrophil homing. VCAM-1 expression was not influenced either by hypoxia, or by MASP-1. In summary, hypoxia potentiates the effect of MASP-1 on ECs, at least partially by increasing PAR expression, resulting in interaction at several levels, which may altogether exacerbate stroke and AMI progression. Our findings suggest that MASP-1 is a potential drug target in the acute phase of atherosclerosis-related diseases.

Unravelling heterogeneous effects of cancer­associated fibroblasts on poor prognosis markers in breast cancer EM­G3 cell line: In vitro­targeted treatment (anti­IL-6, anti­VEGF-A, anti­MFGE8) based on transcriptomic profiling.

Breast cancer is the most frequently diagnosed cancer in women worldwide. Although dramatically increased survival rates of early diagnosed cases have been observed, late diagnosed patients and metastatic cancer may still be considered fatal. The present study's main focus was on cancer­associated fibroblasts (CAFs) which is an active component of the tumor microenvironment (TME) regulating the breast cancer ecosystem. Transcriptomic profiling and analysis of CAFs isolated from breast cancer skin metastasis, cutaneous basal cell carcinoma, and squamous cell carcinoma unravelled major gene candidates such as IL6, VEGFA and MFGE8 that induced co­expression of keratins­8/­14 in the EM­G3 cell line derived from infiltrating ductal breast carcinoma. Western blot analysis of selected keratins (keratin­8, ­14, ­18, ­19) and epithelial­mesenchymal transition­associated markers (SLUG, SNAIL, ZEB1, E­/N­cadherin, vimentin) revealed specific responses pointing to certain heterogeneity of the studied CAF populations. Experimental in vitro treatment using neutralizing antibodies against IL-6, VEGF­A and MFGE8 attenuated the modulatory effect of CAFs on EM­G3 cells. The present study provided novel data in characterizing and understanding the interactions between CAFs and EM­G3 cells in vitro. CAFs of different origins support the pro­inflammatory microenvironment and influence the biology of breast cancer cells. This observation potentially holds significant interest for the development of novel, clinically relevant approaches targeting the TME in breast cancer. Furthermore, its implications extend beyond breast cancer and have the potential to impact a wide range of other cancer types.