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.

Background : Our study aimed to screen and explore the expression of inflammatory factors in keloid patients and to investigate how hyperbaric oxygen (HBO) therapy affects the expression levels of interleukin-12p40 (IL-12p40), macrophage inflammatory protein-1b (MIP-1b), platelet-derived growth factor-BB (PDGF-BB), and interleukin-1 receptor antagonist (IL-1Ra).Objective : 30 patients were randomly selected and divided into the following 3 groups: keloid samples from keloid patients treated with HBO therapy (A), keloid samples from keloid patients treated without HBO therapy (B), and normal control skin samples derived from individuals who had no clear scarring (C). Each group included 10 samples.Methods : Inflammatory factors in the keloid tissues were measured with the MILLIPLEX multiplexed Luminex system. Hematoxylin and eosin staining, immunohistochemical staining, and Western blotting were used to observe the morphological differences in different tissues and the expression levels.Results : The expression levels of inflammatory mediators, including IL-12p40, MIP-1b, PDGF-BB, and IL-1Ra, in keloid tissues were significantly different from those in samples of normal skin. Hematoxylin and eosin staining showed significantly greater inflammatory infiltration in keloid tissue. Significantly different expression levels were observed in group A, B, and C.Conclusion : Significantly altered levels of inflammatory factors in the samples from keloid patients were observed, suggesting that formation of a keloid is potentially related to inflammatory responses. HBO therapy could significantly affect the expression levels of IL-12p40, MIP-1b, PDGF-BB, and IL-1Ra, indicating that the effects of HBO therapy are associated with the attenuation of inflammatory responses.Abbreviations: H&E = hematoxylin and eosin, HBO = hyperbaric oxygen, IL-12p40 = interleukin-12p40, IL-1Ra = interleukin-1 receptor antagonist, MIP-1b = macrophage inflammatory protein-1b, PDGF-BB = platelet-derived growth factor-BB.

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Background:Hyperbaric oxygen therapy (HBOT) has been widely used in the clinical setting. In this study, HBOT therapy was evaluated for its ability to ameliorate the epithelial-to-mesenchymal transition (EMT) phenomenon in keloid tissue.Methods:Keloid patients were randomly divided into two groups: keloid patients (K group, 9 patients) and keloid patients receiving HBOT (O group, 9 patients). A third group with normal skin (S group, 9 patients) was established for control. Before HBOT and surgery, a laser Doppler flowmeter was used to measure the keloid blood supply of patients in the O group. Hematoxylin and eosin (H&E) staining was used to observe morphology. E-cadherin, ZO-1, vimentin, fibronectin, vascular endothelial growth factor (VEGF), and hypoxia inducible factor (HIF)-1α were measured by immunofluorescence staining and Western blot analysis. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to evaluate the mRNA expression level of these factors as well.Results:In the O group, keloid blood perfusion was significantly reduced after patients received HBOT. Compared with the K group, lower expression levels of vimentin, vibronectin, VEGF, and HIF-1α were observed in the O group, whereas the expression of E-cadherin and ZO-1 was significantly higher. The mRNA expression of E-cadherin and ZO-1 was also increased after HBOT.Conclusions:The expression levels of factors related to the EMT phenomenon were significantly reversed in keloid patients after they received HBOT, indicating that HBOT may be an effective therapy against the EMT phenomenon in keloid patients.

4-bit absolute-value detector (AVD), as one of the basic implementations of bit arithmetic with logic circuits, can help grab a better understanding about digital integrated circuits. Conventional 4-bit AVDs scheme in a multi-comparator and multiplexers, or need to consider multiple situations of overflow and carry-in, both of which could make the final circuit to be complex, labyrinthine and inefficient in the meantime. In this paper, a new design of 4-bit AVD is proposed, the topology of which includes a 2’s complement calculator and a specially designed logic circuit known as chain carry adder (CCA). The whole circuit is concise and the critical path is rigorously considered to make it as short as possible. The delay is set to 1.5 times its minimum, which is positively corresponding to the length of the critical path, the energy accordingly reaches its lower limit. Gate sizing and Device Voltage (VDD) optimization are proceeded for the exact purpose of proving that the circuit energy is minimized.

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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.

The failure of reconstructive surgeries remains a challenge for plastic surgeons. Ischemia reperfusion (I/R) injury is considered to be one of the major problems in flap surgery. Necroptosis is a recently discovered and caspase-3-independent programed necrosis. Necrostatin-1 (Nec-1) is a specific inhibitor of necroptosis. Reports indicate that Nec-1 provides protection in ischemic models, such as brain, kidney, and heart. The aim of this study is to investigate the influence of Nec-1 on the I/R process in rat abdominal skin flaps. Methods: Twenty male Sprague-Dawley rats, weighing 280-320 g, were randomly divided into three groups. The extended epigastric skin flap (6 cm × 9 cm) of rats was used. Three hours of complete ischemia was performed using a clamp, and the clamp was then removed to reperfusion the flap. Twenty-four hours after the onset of the reperfusion, the rats were assessed for flap survival and perfusion analysis. One sample (1 cm × 1 cm) was taken for H&E, TUNEL, electron microscopy, IHC staining for RIP-1, and ELISA analysis for caspase-3 activity. Results: Compared to the CTL group, the flap in the Nec-1 group showed a higher survival rate and better blood perfusion. In histological observation, skin flap in the Nec-1 group showed less inflammatory infiltration than the CTL group. The AI in the CTL group was higher than that in the Nec-1 group and showed typical morphological changes of apoptotic cells. In IHC study, RIP-1 expression was higher in the CTL group. But there was no significant difference between the two groups in caspase-3 activity detection.