OBJECTIVE: To investigate the effectiveness of delayed replantation of degloving skin preserved at 4℃ in treatment of limb degloving injuries. METHODS: Between October 2020 and October 2023, 12 patients with limb degloving injuries were admitted. All patients had severe associated injuries or poor wound conditions that prevented primary replantation. There were 7 males and 5 females; age ranged from 29 to 46 years, with an average of 39.2 years. The causes of injury included machine entanglement in 6 cases, traffic accidents in 5 cases, and sharp instrument cuts in 1 case. Time from injury to hospital admission was 0.5-3.0 hours, with an average of 1.3 hours. Injury sites included upper limbs in 7 cases and lower limbs in 5 cases. The range of degloving skin was from 5 cm×4 cm to 15 cm×8 cm, and all degloving skins were intact. The degloving skin was preserved at 4℃. After the patient's vital signs became stable and the wound conditions improved, it was trimmed into medium-thickness skin grafts for replantation. The degloving skin was preserved for 3 to 7 days. At 4 weeks after replantation, the viability of the degloving skin grafts was assessed, including color, elasticity, and sensation of pain. The Vancouver Scar Scale (VSS) was used to assess the scars of the skin grafts during follow-up. RESULTS: At 4 weeks after replantation, 8 cases of skin grafts completely survived and the color was similar with normal skin, with a survival rate of 66.67%. The elasticity of skin grafts (R0 value) ranged from 0.09 to 0.85, with an average of 0.55; moderate pain was reported in 4 cases, mild pain in 3 cases, and no pain in 5 cases. All patients were followed up 12 months. Over time, the VSS scores of all 12 patients gradually decreased, with a range of 4-11 at 12 months (mean, 6.8). CONCLUSION For limb degloving injuries that cannot be replanted immediately and do not have the conditions for deep low-temperature freezing preservation, the method of preserving the degloving skin at 4℃ for delayed replantation can be chosen.
Humans ; Male ; Adult ; Replantation/methods* ; Female ; Degloving Injuries/surgery* ; Middle Aged ; Skin Transplantation/methods* ; Treatment Outcome ; Extremities/injuries* ; Time Factors ; Skin/injuries* ; Tissue Preservation/methods*

Objective:To investigate the effect of tourniquet-reperfusion augmented infrared thermography(TRAIRT) on locating the dominant perforator to assist design of free medial sural artery perforator flap.Methods:The data of patients with skin soft tissue defect of upper limb repaired by free medial sural artery perforator flap in Department of Hand Surgery, Ningbo Sixth Hospital from May 2019 to January 2022 were retrospectively analyzed. Color Doppler ultrasonography (CDU) and TRAIRT were used to locate the dominant perforator auxiliary flap design before surgery and after anesthesia. In the TRAIRT video, the hot spot with "early emergence, high brightness and fast expansion" was selected as the advantageous perforator. During the operation, the flap was elevated and transferred to the affected area to cover the defect wound according to the designed mark points, and fixed by the absorbable sutures with an interrupted suturing method, then end-to-end vascular anastomosis was performed successively. The donor area was sutured directly or sutured with full thickness skin grafts depending on the area of the wound. The donor and recipient areas of the flap were observed and the patients’ satisfaction was recorded. The gold standard was the actual location of the perforating vessel found during the operation. Compared with the gold standard, the location of the perforating vessel explored by TRAIRT and CDU was considered to be accurate (positive) if the distance was less than 10 mm. The sensitivity (accurate number of perforators/actual number of perforators during operation ×100%) and positive predictive value (accurate number of perforators/total number of perforators×100%) of the two methods were calculated, expressed as %, and the sensitivity of the two methods was compared by paired χ2 test. Kappa coefficient was used to analyze the consistency of the two methods to detect perforating vessels. The perforator detection time of TRAIRT and CDU were recorded, expressed as Mean±SD, and statistically analyzed by paired sample t-test. Results:A total of 23 patients were included, consisting of 14 males and 9 females, agd 21-70 years old, average age of 43 years old. The wounds were on forearm in 5 cases, wrist in 2 cases, and hand in 16 cases. The wound area was 4.5 cm × 5.5 cm-6.5 cm × 12.0 cm. Intraoperative flap incision area was 5.0 cm × 6.0cm-7.0 cm × 13.0 cm. After operation, 22 cases of flaps survived, 1 case had superficial necrosis at the distal end, which healed after repeated dressing change. The donor area of flaps healed well, with primary suture in 20 cases and full thickness skin grafting in 3 cases. Postoperative follow-up was 5-16 months (mean 8.4 months). The flaps had no bulge, swelling and abrasion. The texture and color were similar to the medial calf skin, and the scars in the donor and recipient areas were not obvious. The patients were satisfied with the recovery. Among the 23 patients, 49 perforators were found by TRAIRT, 50 perforators were found by CDU, and 53 perforators were found intraoperatively. The sensitivity of TRAIRT and CDU was 88.7% (47/53) and 90.6% (48/53), with no significant differences ( P>0.05), and the positive prediction value was 95.9% (47/49) and 96.0% (48/50) respectively. The Kappa coefficient was 0.89, indicating a good consistency between the two methods. The time required for TRAIRT to detect perforators was significantly shorter than that of CDU, with statistical significance [(6.52±2.02) min vs. (17.87±2.49) min, P<0.01]. Conclusion:TRAIRT has a good consistency with CDU in detection of medial sural artery perforator. The application of TRAIRT in designing medial sural artery perforator flap for wound repair is good, and it has advantages of short time taking, simple operation, economy and non-invasiveness.

Objective To investigate the clinical effect of free posterior interosseous artery perforator flap combined with muscle fascia for repairing soft tissue and extensor tendon defect of hand.Methods Fifteen cases of hand skin soft tissue and extensor tendon defect admitted to Ningbo No.6 Hospital from December 2017 to December 2020 were repaired with free posterior interosseous artery perforator flap combined with extensor carpi ulnaris muscle fascia transplantation,and curative effect was observed.Results All flaps survived and patients were followed up for 6-24 months.The texture and thickness of the flap were satisfactory,and the recovery of the finger extension and flexion function were good.The excellent and good rate of hand tendon repair was 66.7%.In three cases with nerve anastomosis,the skin flap sensation recovered to S3.Conclusion The free posterior interosseous artery perforator flap combined with muscle fascia has a good clinical effect in repairing hand skin soft tissue and tendon defect.

Objective:To investigate the effect of tourniquet-reperfusion augmented infrared thermography(TRAIRT) on locating the dominant perforator to assist design of free medial sural artery perforator flap.Methods:The data of patients with skin soft tissue defect of upper limb repaired by free medial sural artery perforator flap in Department of Hand Surgery, Ningbo Sixth Hospital from May 2019 to January 2022 were retrospectively analyzed. Color Doppler ultrasonography (CDU) and TRAIRT were used to locate the dominant perforator auxiliary flap design before surgery and after anesthesia. In the TRAIRT video, the hot spot with "early emergence, high brightness and fast expansion" was selected as the advantageous perforator. During the operation, the flap was elevated and transferred to the affected area to cover the defect wound according to the designed mark points, and fixed by the absorbable sutures with an interrupted suturing method, then end-to-end vascular anastomosis was performed successively. The donor area was sutured directly or sutured with full thickness skin grafts depending on the area of the wound. The donor and recipient areas of the flap were observed and the patients’ satisfaction was recorded. The gold standard was the actual location of the perforating vessel found during the operation. Compared with the gold standard, the location of the perforating vessel explored by TRAIRT and CDU was considered to be accurate (positive) if the distance was less than 10 mm. The sensitivity (accurate number of perforators/actual number of perforators during operation ×100%) and positive predictive value (accurate number of perforators/total number of perforators×100%) of the two methods were calculated, expressed as %, and the sensitivity of the two methods was compared by paired χ2 test. Kappa coefficient was used to analyze the consistency of the two methods to detect perforating vessels. The perforator detection time of TRAIRT and CDU were recorded, expressed as Mean±SD, and statistically analyzed by paired sample t-test. Results:A total of 23 patients were included, consisting of 14 males and 9 females, agd 21-70 years old, average age of 43 years old. The wounds were on forearm in 5 cases, wrist in 2 cases, and hand in 16 cases. The wound area was 4.5 cm × 5.5 cm-6.5 cm × 12.0 cm. Intraoperative flap incision area was 5.0 cm × 6.0cm-7.0 cm × 13.0 cm. After operation, 22 cases of flaps survived, 1 case had superficial necrosis at the distal end, which healed after repeated dressing change. The donor area of flaps healed well, with primary suture in 20 cases and full thickness skin grafting in 3 cases. Postoperative follow-up was 5-16 months (mean 8.4 months). The flaps had no bulge, swelling and abrasion. The texture and color were similar to the medial calf skin, and the scars in the donor and recipient areas were not obvious. The patients were satisfied with the recovery. Among the 23 patients, 49 perforators were found by TRAIRT, 50 perforators were found by CDU, and 53 perforators were found intraoperatively. The sensitivity of TRAIRT and CDU was 88.7% (47/53) and 90.6% (48/53), with no significant differences ( P>0.05), and the positive prediction value was 95.9% (47/49) and 96.0% (48/50) respectively. The Kappa coefficient was 0.89, indicating a good consistency between the two methods. The time required for TRAIRT to detect perforators was significantly shorter than that of CDU, with statistical significance [(6.52±2.02) min vs. (17.87±2.49) min, P<0.01]. Conclusion:TRAIRT has a good consistency with CDU in detection of medial sural artery perforator. The application of TRAIRT in designing medial sural artery perforator flap for wound repair is good, and it has advantages of short time taking, simple operation, economy and non-invasiveness.

The CRISPR-Cas (clustered regularly interspaced short palindromic repeats and CRISPR-associated) system is an "adaptive immune system" found in the genomes of bacteria and archaea which is mediated by RNA and resists foreign nucleic acid invasion.Take advantage of specific recognition of target nucleic acid, CRISPR-Cas system can efficiently edit their target site or accurately regulate gene expression, and now have been developed into a powerful tool for gene editing.According to the different compositions of the effector complex, the system has been divided into two categories: class 1 (type I, type IV, and type III) and class 2 (type II, type V, and type VI).Class 2 system, like the CRISPR-Cas9, is widely used in basic research due to the earliest discovery and best research.However, class 1 has not been maturely developed and utilized though it makes up 90% of the entire CRISPR-Cas system.In this essay, the classification of subtype, the assembly of Cascade complex, the cleavage and degradation mechanism of Cas3, and the application in gene editing of class 1 type I CRISPR-Cas system will be discussed and summarized to provide new ideas and methods for further mechanism studying and application of this category.

Inflammasome is the body of protein complex which is able to identify different stimulation signals and can in‐duce immune and inflammatory responses when it is activated .NLRP3 inflammasome has been extensively studied in the central nervous system .Microglia ,perivascular macrophages and meningeal macrophages express inflammasomes .The occurrence and development of acute brain infection ,aseptic acute brain injury ,Parkinson disease and Alzheimer disease are closely related to inflammasomes .Based on mechanisms exploration of the inflammasome′s role in the central nervous system disorders ,its tar‐get drug research and development will be greatly addressed in the future .