Objective To provide systematic information for deep understanding and improvement of tension-reducing suture of deep layer skin. Methods The related literature over the years was extensively collected and precisely processed to summarize the characteristics and applications of different tension-reducing suture of deep layer skin. Results Throughout the development of plastic surgery, tension-reducing suture of deep layer skin mainly includes vertical mattress suture and its modified styles, horizontal mattress suture and its modified styles, and some special types of suture technique, and each one of them has its own characteristics and is suitable for wounds with different tension and shape. Conclusion Clinically, surgeons need to select appropriate tension-reducing suture techniques according to specific factors such as wound location and tension, so as to fully reduce the tension of the wound, which can achieve good wound healing and prevent the pathological scaring.
Objective To isolate extracellular vesicles (EVs) from the wound-edge skin tissue of type 2 diabetic foot ulcers and to investigate their effect on wound healing in mice. Methods Twenty 8-week-old male db/db mice were used to establish a full-thickness skin defect wound with a diameter of 1.0 cm on the back, and divided into GW4869 (hydrochloride hydrate) group and DMSO group (control group), with 10 mice in each group. The wound healing rate was calculated on days 3, 6, 9, and 12 after injection. HE staining was used to observe epithelialization and inflammatory cell infiltration on days 7 and 12 after injection. Masson staining was used to observe collagen fiber formation. Immunofluorescence staining was used to detect CD206 and interleukin 1β (IL-1β) expressions in wound tissues. Skin tissues from the wound edge of 30 patients with type 2 diabetic foot ulcer were collected for tissue cutting, enzyme dissociation, gradient size exclusion, differential centrifugation combined with ultra-high speed centrifugation to extract tissue EVs (Dia-EVs), which were identified by transmission electron microscopy and particle size analysis. Twenty 8-week-old male C57BL/6 mice were used to establish a full-thickness skin defect wound with a diameter of 1.0 cm on the back, and divided into Dia-EVs group and PBS group, with 10 mice in each group. The wound healing rate was calculated on days 3, 5, 7, 9, and 12 after injection. HE staining was used to observe epithelialization and inflammatory cell infiltration on days 7 and 12 after injection. Masson staining was used to observe collagen fiber formation. Immunofluorescence staining was used to detect CD206 and IL-1β expressions in wound tissues. In vitro experiments were conducted using RAW264.7 cells, which were divided into three groups: the control group [cultured in PRMI 1640 medium containing 10% fetal bovine serum (FBS)], the M1 group [induced with PRMI 1640 medium containing 10%FBS, 200 ng/mL lipopolysaccharide, and 20 ng/mL interferon γ (IFN-γ) for 48 hours], and the Dia-EVs group (treated with PRMI 1640 medium containing 10%FBS and 40 μg/mL Dia-EVs for 48 hours). The expression levels of CD206 and IL-1β in each group of cells were observed. Results In db/db mice experiment, on days 3, 6, 9, and 12 after injection, the wound healing rate of the GW4869 group was significantly faster than that of the DMSO group (P<0.05). On day 7 after injection, inflammatory cell infiltration in the DMSO group was obvious, and the number of inflammatory cells was significantly higher than that in the GW4869 group (P<0.05). Masson staining showed no obvious new collagen formation in either group. On day 12 after injection, HE staining showed that the GW4869 injection group had completed epithelialization without obvious inflammatory cell infiltration, while the DMSO injection group still had a large number of inflammatory cells infiltrating (P<0.05). Moreover, a large amount of new collagen was formed in the GW4869 group, and the collagen volume ratio was significantly greater than that of the DMSO group (P<0.05). On 7 days after injection, no significant CD206 positive expression was observed in either group, but a large amount of IL-1β positive expression was seen. Moreover, the IL-1β relative expression in the DMSO group was significantly more than that in the GW4869 group (P<0.05). On 12 days after injection, CD206 positive expression was observed in the GW4869 group, while no significant expression was seen in the DMSO group (P<0.05); no obvious IL-1β positive expression was found in the GW4869 group, while the DMSO group still had a large amount of IL-1β positive expression (P<0.05). In C57BL/6 mice experiment, on days 3, 5, 7, 9, and 12 after injection, the wound healing rate of the Dia-EVs group was significantly slower than that of the PBS group (P<0.05). On day 7 after injection, inflammatory cell infiltration in the Dia-EVs group was obvious, and the number of inflammatory cells was significantly higher than that in the PBS group (P<0.05). Masson staining showed no obvious new collagen formation in either group. On day 12 after injection, wound defects still existed in both the Dia-EVs group and the PBS group, but the wound area in the PBS group was narrower. The number of inflammatory cells showed no significant difference (P>0.05), while a large amount of new collagen formation was observed in the PBS group, significantly more than that in the Dia-EVs group (P<0.05). Immunofluorescence results showed that on days 7 and 12 after injection, the number of IL-1β-positive cells in the Dia-EVs group was significantly higher than that in the PBS group (P<0.05), while no significant CD206 positive expression was observed in either group (P>0.05). In vitro experimental results showed that there was no significant difference in the relative expression of CD206 among the three groups (P>0.05). The relative expressions of IL-1β in M1 group and Dia-EVs group were significantly higher than that in the control group (P<0.05), but there was no significant difference between the two groups (P>0.05).Conclusion Dia-EVs delay wound healing in mice by inducing M1 polarization of macrophages, inhibiting M2 transformation, and reducing collagen deposition.
ObjectiveBy applying the mutual corroboration in the diagnosis, we aimed to improve the accuracy of preoperative imaging diagnosis, select the appropriate timing of operation and guide the follow-up time for patients with pulmonary nodules.MethodsClinical data of 1 368 patients with pulmonary nodules undergoing surgical treatment in our department from July 2016 to October 2019 were summarized. There were 531 males and 837 females at age of 44 (21-67) years. The intraoperative findings, images and pathology were classified and analyzed. The imaging pathology and pathological changes of pulmonary nodules were shown as a dynamic process through mutual collaboration and interaction.ResultsOf 1 368 patients with pulmonary nodules, 376 (27.5%) were pure ground-glass nodules, 729 (53.3%) were mixed ground-glass nodules and 263 (19.2%) were solid nodules. Among the pure ground-glass nodules, adenocarcinoma in situ (AIS) accounted for the highest proportion (156 patients), followed by microinvasive adenocarcinoma (MIA, 90 patients), atypical adenomatous hyperplasia (AAH, 85 patients), and benign tumors (20 patients). Among mixed ground-glass nodules, 495 patients were invasive adenocarcinoma (IA) and 207 patients of MIA. In solid nodules, patients were characterized by pathology of either IA (213 patients) or benign tumors (50 patients), and no patient was featured by AAH, AIS or MIA.ConclusionThe mutual collaboration and interaction can improve the accuracy of preoperative diagnosis of pulmonary nodules, and it supports the choice of operation timing and the judgment of follow-up time.
