Necroptosis was found in a rat ischemia/reperfusion injury flap model / 中华医学杂志(英文版)

BACKGROUND@#Necroptosis is a new form of cell death that has been identified as a third pathway causing cell death. In this study, necrostatin-1 (Nec-1) was used to determine whether necroptosis exists in a rat ischaemia/reperfusion injury flap model.@*METHODS@#In this study, twenty male Sprague-Dawley rats were divided randomly into two groups: a control group (CTL group) and a Nec-1 group. Each abdominal skin flap underwent 3 h of ischaemia and then reperfusion. Fifteen minutes before and after reperfusion, phosphate buffer saline (PBS) was administered intraperitoneally to the CTL group, while Nec-1 was administered intraperitoneally to the Nec-1 group. Twenty-four hours after reperfusion, the whole flap was divided equally into 54 sections. Flap blood perfusion was measured. One sample was taken randomly from each row. Morphological changes, apoptosis, receptor-interacting protein-1 (RIP-1) expression and caspase-3 activity were observed and detected. The measurements between the two groups were compared with the independent t-test, and a P value of <0.05 was considered statistically significant.@*RESULTS@#Compared to flaps in the CTL group, flaps in the Nec-1 group showed longer survival rates, better blood perfusion and less inflammatory infiltration. The total flap area considered to have survived was 70.88 ± 10.28% in the CTL group, whereas 80.56 ± 5.40% of the area was found to be living in the Nec-1 group (Nec-1 vs. CTL, t = -2.624, P < 0.05). For some rows, there were significant differences in cell apoptosis between the two groups, the apoptosis index (AI) in rows "9 cm", "7 cm", "6 cm" and "5 cm" was significantly lower in the Nec-1 group than that in the CTL group (Nec-1 vs. CTL, P < 0.05). RIP-1 expression was much lower in the Nec-1 group than that in the CTL group in rows "5 cm" to "9 cm" (Nec-1 vs. CTL, P < 0.05). No significant differences in caspase-3 activity were found.@*CONCLUSION@#According to the results, necroptosis was present in a rat abdominal ischaemia/reperfusion injury flap model.

Hyperbaric oxygen therapy improves the effect of keloid surgery and radiotherapy by reducing the recurrence rate / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

OBJECTIVE@#Keloids are exuberant cutaneous scars that form due to abnormal growth of fibrous tissue following an injury. The primary aim of this study was to assess the efficacy and mechanism of hyperbaric oxygen therapy (HBOT) to reduce the keloid recurrence rate after surgical excision and radiotherapy.@*METHODS@#(1) A total of 240 patients were randomly divided into two groups. Patients in the HBOT group (O group) received HBOT after surgical excision and radiotherapy. Patients in the other group were treated with only surgical excision and radiotherapy (K group). (2) Scar tissue from recurrent patients was collected after a second operation. Hematoxylin and eosin (H&E) staining was used to observe keloid morphology. Certain inflammatory factors (interleukin-6 (IL-6), hypoxia-inducible factor-1α (HIF-1α), tumor necrosis factor-α (TNF-α), nuclear factor κB (NF-κB), and vascular endothelial growth factor (VEGF)) were measured using immunohistochemical staining.@*RESULTS@#(1) The recurrence rate of the O group (5.97%) was significantly lower than that of the K group (14.15%), P<0.05. Moreover, patients in the O group reported greater satisfaction than those in the K group (P<0.05). (2) Compared with the recurrent scar tissue of the K group, the expression levels of the inflammatory factors were lower in the recurrent scar tissue of the O group.@*CONCLUSIONS@#Adjunctive HBOT effectively reduces the keloid recurrence rate after surgical excision and radiotherapy by improving the oxygen level of the tissue and alleviating the inflammatory process.