[Repair of complex wounds on hands after burns or trauma].

Objective: To explore the repair methods and effects of the complex wounds on hands after burns or trauma. Methods: From January 2008 to December 2017, 45 patients (28 males and 17 females, aging 8 to 58 years) with severe hand injuries after burns or trauma combined with deep tissue exposure were admitted to our hospital. Two patients had whole-fingers degloving injuries, 27 patients had dorsal hand injuries, and 16 patients had palmar injuries. After debridement, the area of soft tissue defects was 7 cm×6 cm to 19 cm×12 cm combined with 0.5 cm×0.4 cm to 10.0 cm×4.0 cm of single deep tissue exposure. Different repairing methods were adopted according to the area and location of deep tissue exposure. Five patients with small area exposure were treated with artificial dermis+ vacuum sealing drainage (VSD)+ autogenous skin grafting. Thirty-eight patients with unilateral large area exposure on palm or dorsum were treated with segmented ligation of abdominal thin flaps (with area of 8 cm×7 cm to 15 cm×9 cm). Two patients with bilateral large area exposure in dorsal and palmar hands were treated with modified abdominal bag-shaped delayed thin flaps (with area of 12 cm×5 cm to 12 cm×9 cm and 12 cm×6 cm to 14 cm×9 cm). The donor sites were directly sutured or repaired with intermediate split-thickness skin or adjacent flap. The survival of grafts and flaps was observed, number of operations, wound healing time, and follow-up were recorded. Results: (1) Among the patients receiving artificial dermis+ VSD+ autogenous skin grafting, the wounds of 3 patients were healed after 2 operations, and 2 patients had artificial dermis infection and lysis, and tendon necrosis, which were healed after 3 operations. The wound healing time of 5 patients was 14 to 33 days post injury. During the follow-up of 3 months, the affected hands were in good shape with soft texture and fewer scars, and functional evaluation of hand was good in 3 cases and modest in 2 cases. (2) The patients receiving segmented ligation of abdominal thin flaps all underwent 2 operations without flap necrosis. The wound healing time was 2 to 3 weeks post injury. Thirty-five patients underwent one to six-years' follow-up, which showed that the flaps were in good shape and color with soft texture, and the functional evaluation of hand was excellent in 25 cases, good in 7 cases, and modest in 3 cases. Three patients were lost to follow-up. (3) In the 2 patients receiving modified abdominal bag-shaped delayed thin flaps, all flaps survived after 5 operations, the wounds were healed on post injury day 22 and 24 respectively, the shape and texture of the affected hands was good with no bloated appearance after separating fingers and revision. During the follow-up of 2 years, the functional evaluation of hand was good in 2 cases. Conclusions: For the complex wounds on hands after burns or trauma, if the area of deep tissue exposure is small, artificial dermis+ VSD+ autogenous skin grafting should be adopted, which has good effects. If the area of unilateral deep tissue exposure is large, segmented ligation of abdominal thin flap should be adopted; if the area of bilateral deep tissue exposure is large, modified abdominal bag-shaped delayed thin flap should be adopted. These methods can reduce the number of operations, shorten wound healing time, and obtain good shape and function of hands.

Argininosuccinate lyase in enterocytes protects from development of necrotizing enterocolitis.

Necrotizing enterocolitis (NEC), the most common neonatal gastrointestinal emergency, results in significant mortality and morbidity, yet its pathogenesis remains unclear. Argininosuccinate lyase (ASL) is the only enzyme in mammals that is capable of synthesizing arginine. Arginine has several homeostatic roles in the gut and its deficiency has been associated with NEC. Because enterocytes are the primary sites of arginine synthesis in neonatal mammals, we evaluated the consequences of disruption of arginine synthesis in the enterocytes on the pathogenesis of NEC. We devised a novel approach to study the role of enterocyte-derived ASL in NEC by generating and characterizing a mouse model with enterocyte-specific deletion of Asl (Asl(flox/flox); VillinCre(tg/+), or CKO). We hypothesized that the presence of ASL in a cell-specific manner in the enterocytes is protective in the pathogenesis of NEC. Loss of ASL in enterocytes resulted in an increased incidence of NEC that was associated with a proinflammatory state and increased enterocyte apoptosis. Knockdown of ASL in intestinal epithelial cell lines resulted in decreased migration in response to lipopolysaccharide. Our results show that enterocyte-derived ASL has a protective role in NEC.

Pain, motor and gait assessment of murine osteoarthritis in a cruciate ligament transection model.

OBJECTIVE: The major complaint of Osteoarthritis (OA) patients is pain. However, due to the nature of clinical studies and the limitation of animal studies, few studies have linked function impairment and behavioral changes in OA animal models to cartilage loss and histopathology. Our objective was to study surrogate markers of functional impairment in relation to cartilage loss and pathological changes in a post-traumatic mouse model of OA. METHOD: We performed a battery of functional analyses in a mouse model of OA generated by cruciate ligament transection (CLT). The changes in functional analyses were linked to histological changes graded by OARSI standards, histological grading of synovitis, and volumetric changes of the articular cartilage and osteophytes quantified by phase contrast micro-computed tomography (µCT). RESULTS: OA generated by CLT led to decreased time on rotarod, delayed response on hotplate analysis, and altered gait starting from 4 weeks after surgery. Activity in open field analysis did not change at 4, 8, or 12 weeks after CLT. The magnitude of behavioral changes was directly correlated with higher OARSI histological scores of OA, synovitis in the knee joints, cartilage volume loss, and osteophyte formation. CONCLUSION: Our findings link functional analyses to histological grading, synovitis, comprehensive three-dimensional assessment of cartilage volume and osteophyte formation. This serves as a reference for a mouse model in predicting outcomes of OA treatment.