Liver transplantation (LT) has become a standard treatment for end-stage liver diseases, and graft injury is intricately associated with poor prognosis. Granzyme B (GZMB) plays a vital role in natural killer (NK) cell biology, but whether NK-derived GZMB affects graft injury remains elusive. Through the analysis of single-cell RNA-sequencing data obtained from human LT grafts and the isolation of lymphocytes from mouse livers following ischemia-reperfusion injury (IRI), we demonstrated that 2NK cells with high expression of GZMB are enriched in patients and mice. Both systemically and liver-targeted depletion of NK cells led to a notable reduction in GZMB⁺ cell infiltration, subsequently resulting in diminished graft injury. Notably, the reconstitution of Il2rg ^-/- Rag2 ^-/- mice with purified Gzmb-KO NK cells demonstrated superior outcomes compared to those with wild-type NK cells. Crucially, global knockout of GZMB and pharmacological inhibition exhibited remarkable improvements in liver function in both mouse IRI and rat LT models. Moreover, a phosphorylated derivative of FDA-approved vidarabine was identified as an effective inhibitor of mouse GZMB activity by molecular dynamics, which could provide a potential avenue for therapeutic intervention. Therefore, targeting NK cell-derived GZMB during the LT process suggests potential therapeutic strategies to improve post-transplant outcomes.

Background: Clinical dexamethasone (DEX) treatment or stress in bovines results in extensive physiological changes with prominent hyperglycemia and neutrophils dysfunction. Objectives: To elucidate the effects of DEX treatment in vivo on cellular energy status and the underlying mechanism in circulating neutrophils. Methods: We selected eight-month-old male bovines and injected DEX for 3 consecutive days (1 time/d). The levels of glucose, total protein (TP), total cholesterol (TC), and the proinflammatory cytokines interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α in blood were examined, and we then detected glycogen and adenosine triphosphate (ATP) content, phosphofructosekinase-1 (PFK1) and glucose-6-phosphate dehydrogenase (G6PDH) activity, glucose transporter (GLUT)1, GLUT4, sodium/glucose cotransporter (SGLT)1 and citrate synthase (CS) protein expression and autophagy levels in circulating neutrophils. Results: DEX injection markedly increased blood glucose, TP and TC levels, the Ca 2+ /P 5+ ratio and the neutrophil/lymphocyte ratio and significantly decreased blood IL-1β, IL-6 and TNF-α levels. Particularly in neutrophils, DEX injection inhibited p65-NFκB activation and elevated glycogen and ATP contents and SGLT1, GLUT1 and GR expression while inhibiting PFK1 activity, enhancing G6PDH activity and CS expression and lowering cell autophagy levels. Conclusions DEX induced neutrophils glucose uptake by enhancing SGLT1 and GLUT1 expression and the transformation of energy metabolism from glycolysis to pentose phosphate pathway (PPP)-tricarboxylic acid (TCA) cycle. This finding gives us a new perspective on deeper understanding of clinical anti-inflammatory effects of DEX on bovine.

Objective: To provide clinical guidance for clinical selection, through retrospective analysis for the advantages and disadvantages of superficial iliac circumflex artery and lateral circumflex femoral artery perforator flap in wound repair. Methods: From July 2016 to January 2018, 89 cases were repaired with superficial iliac circumflex artery or lateral femoral circumflex artery perforator flap, including 32 cases of superficial circumflex iliac artery perforator flap, 18 cases of upper limb, 6 cases of face and neck, and 8 cases of lower extremity. There were 52 cases of lateral circumflex femoral artery perforator flap, 21 cases of upper limb, 2 cases of neck, 3 cases of trunk, 26 cases of lower extremity, 5 cases of superficial circumflex iliac artery perforator flap combined with lateral femoral circumflex artery perforator flap, 3 cases of upper limb and 2 cases of lower extremity. The perforators of superficial circumflex iliac artery or (and) lateral circumflex femoral artery were detected by portable Doppler flow detector before operation. According to the wound size, the superficial circumflex artery perforator flap or (and) lateral circumflex femoral artery perforator flap was or (were) designed and resected. End-to-end or end-to-side anastomosis was performed in vascular pedicle. In the combined resection group, the end-to-end or end-to-side anastomosis of the perforator of the lateral circumflex thigh artery was performed, and the pedicled part of the superficial circumflex iliac artery was used for supercharging. Results: All the flaps survived successfully except one combined flap had tip necrosis on the superficial iliac circumflex artery perforator flap part. and healed after 2 weeks of dressing change. Venous crisis occurred on the first day after operation of superficial iliac circumflex artery perforator flap in 1 case.10 cases of lateral femoral circumflex artery perforator flap were slightly bloated and 3 cases returned to hospital for secondary thinning. All the flaps were soft in texture, satisfactory in shape and function, and numbed in the small area of the donor region of the perforator flap of lateral femoral circumflex artery in the early stage. All the patients had no severe complications after follow-up. Conclusions The perforator flap of superficial iliac circumflex artery and lateral femoral circumflex artery are ideal donor areas for wound repair. The perforator flap of superficial iliac circumflex artery is preferred for small area wound, hand wound and small bone defect. Lateral circumflex femoral perforator flap is suitable for all trunk and limbs with large or complex wounds.

Objective: To investigate the effects of free mini-flap on tibial side of third toe on repairing skin and soft tissue defect of finger pulp at the end of finger. Methods: From August 2013 to May 2017, 18 patients with skin and soft tissue defect of finger pulp at the end of finger were admitted to our unit, with 12 men and 6 women aged 16 to 54 years. As the skin and soft tissue defect sites, there were 3 cases of thumb, 8 cases of index finger, 4 cases of middle finger, and 3 cases of ring finger. The area of defects ranged from 2.0 cm×1.4 cm to 3.5 cm×2.4 cm. Free mini-flaps on tibial side of third toes were designed according to area and shape of defects, and the length and width of flaps were 0.1 to 0.2 cm longer than the length and width of the defects, respectively. The area of flaps ranged from 2.1 cm×1.5 cm to 3.7 cm×2.6 cm. The end-to-end anastomosis of subcutaneous veins of flaps and superficial veins of the finger-palm side or superficial dorsal digital vein, the end-to-end tension-free anastomosis of the base metatarsal arteries on tibial side of third toe and proper digital arteries of recipient finger were performed. Besides, anastomosis of base metatarsal nerve on tibial side of third toe and proper digital nerve of recipient finger was performed. The donor sites on feet were sutured directly or repaired with full-thickness skin grafts on medial upper leg of the same side. The survival of flaps after operation and the follow-up of patients were observed. Results: All flaps survived well, with good blood supply. Among the 18 patients, 2 patients lost to follow-up, and 16 patients were followed up for 4 to 36 months. The shape and texture of flaps were good. After reconstruction, finger pulps at the end of finger were plump, with fingerprint. Function of the finger restored well, and the two-point discriminatory distances of flaps were 5 to 10 mm. The donor sites on feet of 14 patients healed after the operation, the other 2 patients had necrosis on edge and central area of skin grafts, and the necrotic area healed after dressing change. The skin graft areas on feet were wear-resistant, with slight damage to donor sites and did not influence shoes wearing and walking. Besides, patients did not feel uncomfortable. Conclusions Skin and soft tissue defects of finger pulp at the end of finger repaired by free mini-flaps on tibial side of third toe are with good shape and slight damage to donor sites, and the operation is simple. It is worthy of popularization and application in clinic.

Objective: To explore the clinical effects of heel lateral flap in repair of skin and soft tissue defects at posterior heel region. Methods: From September 2007 to April 2016, 24 patients (17 males and 7 females, aged 16-70 years) with skin and soft tissue defects at posterior heel region were admitted to our department. The size of skin and soft tissue defects after debridement ranged from 3.0 cm×2.0 cm to 5.0 cm×4.0 cm. The defects were repaired with heel lateral flaps, with size ranging from 3.5 cm×2.5 cm to 6.0 cm×5.0 cm. The flaps were transferred to the donor sites through the loose subcutaneous tunnel. The donor site was repaired by full-thickness skin graft collected from inguinal region. The survival of flaps and the follow-up of patients were observed. Results: All flaps of 24 patients survived successfully. The recipient sites and donor sites were all healed. The patients all had follow-up of 6 to 24 months. At the last follow-up, the flaps were in good shape, with nearly normal color and soft texture. There were 6 cases of grade S3 sensation and 16 cases of grade S3⁺ sensation. The distance of two-point discrimination of flaps ranged from 6 to 11 mm. The lateral foot skin grafts healed well, and the skin of the lateral foot was numb in the range of 4.0 cm×2.0 cm to 9.0 cm×3.0 cm. Conclusions Heel lateral flap can not only repair the skin and soft tissue defects in the posterior region, but also reconstruct the sensory function of the posterior region. It is an ideal method to repair the skin and soft tissue defects in the posterior region.

Objective: To explore the effect of the perforator flap of the proper digital artery on the ulnar or radial side of the finger in the treatment of webbed scar contracture of the same finger in child. Methods: From January 2012 to January 2016, 26 children who were treated with dressing change after burn of finger and then had webbed scar contracture along with growth and development were hospitalized in our unit, involving a total of 50 fingers. There were 14 males and 12 females among the children aged from 2 to 14 years. After the scar was dissected and released, the wound area ranged from 1.6 cm×1.0 cm to 5.0 cm×2.6 cm. The perforator flap of the proper digital artery of the ulnar or radial side of the same finger was used to repair the wound. The flap area ranged from 1.8 cm×1.0 cm to 4.6 cm×1.8 cm. The donor sites were sutured directly. The residual wounds in donor and recipient sites were repaired by full-thickness skin graft collected from inguinal area/adjacent area or adjacent perforator flap. The postoperative development and function of the fingers were followed up and observed. The range of motion of the fingers was evaluated according to the Chinese Medical Association Hand Surgery Society′s upper limb functional evaluation trial standard, the Kantor Scar Cosmesis Assessment and Rating Scale was used to score the scar of finger, and the latest data were recorded. Results: The flaps and skin grafts survived successfully after operation. The patients were followed up for 6 to 24 months. The perforator flaps of the proper digital artery on the ulnar or radial side of the finger survived well at the latest follow-up, with good color and texture and a two-point discrimination distance of 9 to 12 mm. There was no contracture of the fingers, a little pigmentation in the skin graft area, no flexion deformity of the fingers, no lateral bending of the fingers to the flap-harvesting side, and no scar contracture at the webs of the fingers. Compared with that of healthy side, the development of finger was not obviously abnormal. The range of motion of the fingers was excellent in 38 fingers and good in 12 fingers, and the scar score of the fingers was 2-3 points in 31 fingers, 4-7 points in 15 fingers, and 8-10 points in 4 fingers. Conclusions The efficacy of perforator flap of the proper digital artery of the ulnar or radial side of finger in the treatment of the webbed scar contracture of the same finger in child is reliable, with high postoperative survival rate of the flap, better color and texture, and fewer complications, which can avoid the risk of re-contracture of the finger in a short period after operation, and does not affect the growth and development of the finger.

Objective: To explore the feasibility of preoperative designing for anterolateral femoral flap using three longitudinal and five transversal strategy. Methods: From September 2015 to January 2017, 71 patients (73 pieces) were treated using anterolateral thigh flap in the Affiliated Hospital of Zunyi Medical University. There were 48 males and 23 females, with the age of (36±18) years. The three longitudinal and five transversal designing was performed before operation. Portable Doppler ultrasound was used to detect the piercing-out position (P point) of perforators in Ⅰ, Ⅱ, Ⅲ, Ⅳ areas. The diameter, direction and length (lower subcutaneous segment of perforators) of perforators after leaving piercing-out position were observed during the operation. The piercing-in positions on superficial fascia and the dermis were observed. Results: The data of 71 adults (73 legs) were evaluated. Before and during the operation, all the perforations were found in Ⅰ, Ⅱ, Ⅲ and Ⅳ areas. The number of perforators in region Ⅰ was 1.32±0.33, with the diameter of perforator at the piercing-out position was (0.79±0.13) mm. The length of subfascial segment of perforators was (1.54±0.97) cm, and the direction was oblique superolateral. The number of perforators in Ⅱ region was 1.21±0.53, with the diameter of perforator at the piercing-out position was (0.63±0.13) mm. The length of subfascial segment of perforators was (2.25±0.54) cm, and the direction was oblique inferoanterior. The distance form piercing-in position to line L was (0.84±0.42) cm. The number of perforators in the Ⅲ area was 2.22±0.49, with the diameter of perforators at the piercing-out position was (0.53±0.12) mm. The length of subfascial segment of perforator was (1.96±0.44) cm, and the direction was oblique inferoanterior. The distance between piercing-in positions to line L was (0.74±0.51) cm. The number of perforators in region Ⅳ was 1.41±0.72, with the length of subfascial segment of perforators was (1.22±0.45) cm and the direction was oblique inferolateral. There were 27 cases with oblique perforators, accounting for 37% of the total number of thighs. Conclusions This three longitudinal and five transversal designing is helpful to detect the expenditure point in the anterolateral femoral region, and is assistant to skin flap designing.

Objective To investigate the clinical effect of relaying reversed peroneal artery perforator flaps in repairing skin and soft tissue defects at ankle and donor site.Methods A retrospective case series study was conducted on the clinical data of 23 cases of skin and soft tissue defects at ankle and donor site from September 2015 to May 2017.There were 16 males and seven females,with an average age of 35 years (range,18-69 years).The soft tissue defects of ankle ranged from 4.0 cm ×4.0 cm to 11.0 cm × 7.0 cm.The distal perforator flap of the peroneal artery was firstly cut and used to repair the soft tissue defect of the ankle.The proximal perforator flap of the peroneal artery was used to repair the first donor site,and the second donor site was directly sutured at stage Ⅰ.The perforator flap area ranges of the distal and the proximal perforator of the peroneal artery were 6.0 cm ×5.0 cm to 14.0 cm × 8.0 cm and 7.5 cm × 4.0 cm to 14.0 cm × 5.0 cm,respectively.The shape of recipient area and donor area were observed.The clinical effects were evaluated by American Orthopedic Foot and Ankle Association (AOFAS) score and Weber two-point discrimination test.Results All patients were followed up for 6-19 months (mean,12 months).One case had partial necrosis of distal skin of ankle flap after operation and recovered 2 weeks after dressing change.All the other flaps survived smoothly in the first stage.The first donor site had no sunken area or rupture.Some linear scar remained at the second donor site,which did not affect the overall appearance.The flaps were smooth in appearance,good in texture,and close to normal color.The AOFAS score of the foot was 95-98 points,and the distance of two-point discrimination of flaps ranged from 8 to 10 mm.Conclusions The relaying reversed peroneal artery perforator flap has abundant blood supply,and the operation site is located at the lateral crural region,without sacrificing the main artery.It can improve the appearance and function of the first donor area while repairing the soft tissue defect of the ankle.

Objective To prospectively summary the piercing-out position,direction,length and piercing-in position of perforator,and investigate the feasibility of preoperative design and optimization of the anterolateral thigh flap and its clinical application.Methods All 58 cases of anterolateral thigh flaps were designed and taken from the lateral thigh area from January,2014 to January,2016.Portable Doppler ultrasound was used before an operation to detect the piercing-out position (point P) of perforators.The direction and length (lower subcutaneous segment of perforators) of perforators after leaving piercing-out position were observed during the operation.And the piercing-in positions (point P') on superficial fascia and the dermis were observed.Based on this,we added line B (anterior superior spine-lateral femoral epicondyle) and line C (anterior superior spine-the middle point of superior border of patella) in the lateral and anterior side of original ilium-patella line in the thigh (line A),respectively.Results All perforators found in 58 cases before and during the operations were located on line A or between line A and line B.No perforators were found between line A and line C.Perforators walked toward the anterior medial side after leaving the muscle membrane.The perforator vascular subcutaneous segment (distance between point P and point P') was (2.02±0.23) cm.There was rectus muscle branch in the descending branch of lateral femoral circumflex artery,while no rectus muscle cutaneous branch was seen.20 cases were designed by one-line method,12 cases were designed by two-line method,while 26 cases were designed by three-line method.Conclusion Advanced three-line method is beneficial to detect of the perforators on the anterior thigh lateral region and to reduce the intraoperative injury perforator vessels at the puncture point.Clinical application of the anterior lateral thigh flap is simple and reliable.

Objective To investigate the application of anterolateral thigh (ALT) free flap preserving multiple perforators descending from lateral circumflex femoral artery (LCFA) in reconstruction of complex defects of children extremities.Methods From January,2016 to January,2017,7 children admitted with soft tissue defects were reconstructed with ALT free flap preserving multiple perforitors descending from LCFA.According to body surface projection and distribution patterns of perforators descending from LCFA,preoperative portable Doppler was used to localize these perforators.Fascia lata harvest was spared for those without ligament and articular joint reconstruction.Defects and fascia lata was closed primarily.All patients were followed up at regular intervals.Results Follow-up period was 3-9 months(mean,6.5 months.Follow-up methods include on-site follow-up,wechat follow-up,telephone follow-up,etc.).The color of ALT flaps was normal.The texture of ALT flap was good.The linear scar in donor sites was found.The paresthesia around incision in donor sites was complained of.Postoperative appearance and function of injured limbs was satisfactory.Conclusion Design of Unipaddled or multipaddled ALT free flap with multiple perforators descending from LCFA is flexible.Perforators are thick and consistent.ALT flap with multiple perforators descending from LCFA is an ideal one to be used in reconstruction of complex soft tissue defects.