Inflammation-Responsive Hydrogel Accelerates Diabetic Wound Healing through Immunoregulation and Enhanced Angiogenesis.

Angiogenesis is a prominent component during the highly regulated process of wound healing. The application of exogenous vascular endothelial growth factor (VEGF) has shown considerable potential in facilitating angiogenesis. However, its effectiveness is often curtailed due to chronic inflammation and severe oxidative stress in diabetic wounds. Herein, an inflammation-responsive hydrogel incorporating Prussian blue nanoparticles (PBNPs) is designed to augment the angiogenic efficacy of VEGF. Specifically, the rapid release of PBNPs from the hydrogel under inflammatory conditions effectively alleviates the oxidative stress of the wound, therefore reprogramming the immune microenvironment to preserve the bioactivity of VEGF for enhanced angiogenesis. In vitro and in vivo studies reveal that the PBNPs and VEGF co-loaded hydrogel is biocompatible and possesses effective anti-inflammatory properties, thereby facilitating angiogenesis to accelerate the wound healing process in a type 2 diabetic mouse model.

Computed tomography image fusion, Coaxial guidewire technique, Fast intraprocedural cortisol testing technique improves success rate and decreases radiation exposure, procedure time, and contrast use for adrenal vein sampling.

BACKGROUND: Adrenal vein sampling (AVS) is recommended for discriminating patients with unilateral primary aldosteronism from bilateral disease. However, it is a technically demanding procedure that is markedly underused. We developed a computed tomography image fusion, coaxial guidewire technique, fast intraprocedural cortisol testing (CCF) technique to improve AVS success rate, which combines CT image fusion, coaxial guidewire technique, and fast intraprocedural cortisol testing. OBJECTIVE: To evaluate the effectiveness and safety of the AVS--CCF technique. METHODS: We retrospectively evaluated 105 patients who undervent AVS from June 2016 to October 2020. There were 51 patients in the AVS--CCF group and 54 patients in the AVS group. We compared two groups with technical success rate, procedure time, radiation exposure, volume of contrast medium, and complications (adrenal vein rupture, dissection, infarction, or thrombosis; intraglandular or periadrenal hematoma; and contrast-induced nephropathy). RESULTS: The technical success rate was higher for AVS--CCF than for AVS without CCF (98 vs. 83.3% for bilateral adrenal veins, P = 0.016). AVS--CCF was associated with a shorter procedure time (63.6 ±â€Š24.6 vs. 94.8 ±â€Š40.8 min, P < 0.001), shorter fluoroscopy time (15.6 ±â€Š12.6 vs. 20.4 ±â€Š15.0 min, P = 0.043), and lower contrast medium volume (25.10 ±â€Š21.82 vs. 44.1 ±â€Š31.0 ml, P < 0.001). There were no significant differences between groups with respect to the time for cannulating the left or right adrenal vein or the peak skin radiation dose. Adrenal vein rupture occurred in 14 patients and intraglandular hematoma in 1 patient. CONCLUSION: The CCF technique during AVS not only contributed to improved technical success rates but also associated with decreased procedure time, radiation exposure, and contrast medium volume.

ASMq protects against early burn wound progression in rats by alleviating oxidative stress and secondary mitochondria­associated apoptosis via the Erk/p90RSK/Bad pathway.

Burn wounds present an evolutionary progression, in which the initial wound tissue deepens and expands following thermal injury. Progressive tissue damage in the zone of stasis may worsen burn injury, which is associated with oxidative stress and secondary apoptosis, and worsen the prognosis of patients with burn wounds. The mitochondrial apoptotic pathway is involved in receiving oxidative signals and regulating tissue apoptosis. Previously, Abnormal Savda Munziq (ASMq), a natural compound of traditional Uyghur Medicine, which includes ten types of herb, has been reported to exhibit a number of effects, including anti­inflammatory, antioxidative and anti­apoptotic activities. The present study demonstrated that ASMq protected against early burn wound progression following thermal injury in rats; this effect may be mediated by its ability to attenuate oxidative stress­induced mitochondria­associated apoptosis. The present study may provide a novel therapeutic method to prevent early burn wound progression following burn injury.

Rare Skin Fistulas Relating to Ascending Colonic Carcinoma: An Unusual Mode of Revelation.

Chronic or nonhealing wounds is a complex disease influenced by a multitude of factors, such as infection, ischemia, malnutrition, and diabetes and infrequently relates to retroperitoneal carcinoma. We present a case of an adenocarcinoma of ascending colon in a 68-year-old male who had lumbago and waist fistulas with retroperitoneal abscesses preceding other signs or symptoms of colonic malignancy. Supplemental information regarding the diagnosis and treatment of nonhealing wounds and colon carcinoma has also been included in the report. Adenocarcinoma of ascending colon is rarely associated with nonhealing wounds; nevertheless, it should be considered in cases with long-term healing complications. Precise diagnostic deliberation is crucial in the management and treatment of all chronic and long-term nonhealing lesions, and appropriately performed biopsies are essential to determine whether malignancy is the primary cause.

Astaxanthin protects against early burn-wound progression in rats by attenuating oxidative stress-induced inflammation and mitochondria-related apoptosis.

Burn-wound progression can occur in the initial or peri-burn area after a deep burn injury. The stasis zone has a higher risk of deterioration mediated by multiple factors but is also considered salvageable. Astaxanthin (ATX), which is extracted from some marine organisms, is a natural compound with a strong antioxidant effect that has been reported to attenuate organ injuries caused by traumatic injuries. Hence, we investigated the potential effects of ATX on preventing early burn-wound progression. A classic "comb" burn rat model was established in this study for histological and biological assessments, which revealed that ATX, particularly higher doses, alleviated histological deterioration in the stasis zone. Additionally, we observed dose-dependent improvements in oxidative stress and the release of inflammatory mediators after ATX treatment. Furthermore, ATX dose-dependently attenuated burn-induced apoptosis in the wound areas, and this effect was accompanied by increases in Akt and Bad phosphorylation and a downregulation of cytochrome C and caspase expression. In addition, the administration of Ly 294002 further verified the effect of ATX. In summary, we demonstrated that ATX protected against early burn-wound progression in a rat deep-burn model. This protection might be mediated by the attenuation of oxidative stress-induced inflammation and mitochondria-related apoptosis.

The progress and challenges for dermal regeneration in tissue engineering.

Wound healing is an inherent response resulting in the restoration of tissue integrity. It is a complex process involving cell migration, proliferation, differentiation, apoptosis, and the synthesis and remodeling of the extracellular matrix (ECM). The dermal tissue is an important component of skin that acts as a connecting link between the epidermis and hypodermis. The appearance of scars and contractures after autologous split-thickness skin transplantation or single epidermis diaphragm transplantation for full skin defects indicates that the dermal tissue plays an important role in skin regeneration. Theoretically, dermis cannot regenerate like the liver, bone and epidermis after being destroyed by burns or avulsion. Scarring is hard to avoid during the process of natural healing. However, if the dermis could be reconstructed perfectly, this would be a breakthrough in the methods used for wound healing. In this review, we summarize recent research about dermal regeneration and discuss the probability of advances in the field. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1208-1218, 2017.

Polyurethane membrane/knitted mesh-reinforced collagen-chitosan bilayer dermal substitute for the repair of full-thickness skin defects via a two-step procedure.

The advent of dermal substitutes provides a revolutionary strategy for the repair and reconstruction of deep skin defects. Dermal substitutes form a regenerative template that provides the porous structure and mechanical support necessary to guide cell migration, deposition of the extracellular matrix (ECM) and angiogenesis. Commercially available dermal substitutes, particularly collagen-based dermal scaffolds, are widely used in clinical practice. However, the poor mechanical properties of collagen-based dermal scaffolds compromise their biological effects, as well as the repair outcomes. Here, we describe a bilayer dermal substitute prepared by integrating a hybrid dermal scaffold with a polyurethane (PU) membrane to obtain a PU membrane/knitted mesh-reinforced collagen-chitosan bilayer dermal substitute (PU-PLGAm/CCS). The morphology of PU-PLGAm/CCS was investigated and, to characterize the effects of PU-PLGAm/CCS on tissue regeneration, dermal substitutes were transplanted to repair full-thickness skin wounds in Sprague-Dawley rats using a two-step surgical procedure. These results were then compared with those obtained using the PELNAC™ Artificial Dermis. In the weeks after the first operation, wound changes were analysed based on macroscopic observations, and tissue specimens were harvested for histology, immunohistochemistry, immunofluorescence real-time quantitative PCR, and Western blotting analysis. Following the second operation (i.e., transplantation of split-thickness skin grafts), the repair outcomes were investigated based on the mechanical strength and ECM expression. PU-PLGAm/CCS significantly inhibited wound contracture, promoted angiogenesis, and facilitated the ordered arrangement of neotissue, such that the repair outcomes were improved in the PU-PLGAm/CCS group compared with the PELNAC™ group. In conclusion, the favourable microstructure and structural stability of dermal substitutes facilitated tissue regeneration. PU-PLGAm/CCS achieved a balance between porous structure, biocompatibility and mechanical properties for dermal regeneration by integrating the advantages of biological and synthetic biomaterials, which demonstrates its potential for skin tissue engineering.

Astaxanthin attenuates early acute kidney injury following severe burns in rats by ameliorating oxidative stress and mitochondrial-related apoptosis.

Early acute kidney injury (AKI) is a devastating complication in critical burn patients, and it is associated with severe morbidity and mortality. The mechanism of AKI is multifactorial. Astaxanthin (ATX) is a natural compound that is widely distributed in marine organisms; it is a strong antioxidant and exhibits other biological effects that have been well studied in various traumatic injuries and diseases. Hence, we attempted to explore the potential protection of ATX against early post burn AKI and its possible mechanisms of action. The classic severe burn rat model was utilized for the histological and biochemical assessments of the therapeutic value and mechanisms of action of ATX. Upon ATX treatment, renal tubular injury and the levels of serum creatinine and neutrophil gelatinase-associated lipocalin were improved. Furthermore, relief of oxidative stress and tubular apoptosis in rat kidneys post burn was also observed. Additionally, ATX administration increased Akt and Bad phosphorylation and further down-regulated the expression of other downstream pro-apoptotic proteins (cytochrome c and caspase-3/9); these effects were reversed by the PI3K inhibitor LY294002. Moreover, the protective effect of ATX presents a dose-dependent enhancement. The data above suggested that ATX protects against early AKI following severe burns in rats, which was attributed to its ability to ameliorate oxidative stress and inhibit apoptosis by modulating the mitochondrial-apoptotic pathway, regarded as the Akt/Bad/Caspases signalling cascade.