ABSTRACT
Objective:To explore the clinical application of free chimeric medial femoral condyle osteofascial free flap (CMFCOF) in the treatment of traumatic composite bone and soft tissue defect of hand and foot.Methods:Between January, 2015 and March, 2020, 8 patients with traumatic composite bone and soft tissue defect in hand and foot were treated with CMFCOF. Of the 8 patients, there were 6 males and 2 females, with an average age of 41 (range, 24 to 56) years. The causes of injury included 3 of traffic accident, 3 of machine crush and 2 of crush. Two cases had proximal phalanx defect, 3 with metacarpal bone and 3 with metatarsal bone. The time between injury to the flap repair were 2 to 120 (mean, 84) days. The size of bone defect ranged from 2.0 cm×1.2 cm×1.2 cm to 4.4 cm× 3.0 cm×2.3 cm. The soft tissue defect ranged from 2.0 cm×1.4 cm to 5.6 cm×4.5 cm. All bone defects were on the diaphysis, without involvement of joints. Two cases had tendon defect. According to the defect of bone and soft tissue, the CMFCOF was prepared and skin graft was performed on the surface of its fascial flap.Results:The average time of flap harvesting was 53(52-96) minutes. All donor sites were directly closed. All flaps and skin grafts achieved stage I survival. All patients entered 9-16 months of follow-up, with an average of 14.5 months. The average healing time of bone was 7.5 (range, 6-10) weeks. At the last follow-up review, all flaps were not thinned. The function of donor site was restored well, without weight bearing disorder and paraesthesia in the anterior patella area. According to the trial standard of Digit Function Evaluation of the Hand Surgery Society of Chinese Medical Association, 3 patients were rated as excellent, 1 was good and 1 was fair. According to the Maryland foot evaluation criteria, 3 patients were rated as excellent for recovered with normal weight-bearing walking.Conclusion:CMFCOF can achieve satisfactory results in repairing composite bone and soft tissue defect of hand or foot. The flap has the advantages in simple operation, high quality of bone and concealed donor site.
ABSTRACT
Objective To study the role of protective antigen(PA)and N-terminal segment of lethal factor (LFn)in the entrance of EGFP(enhanced green fluorescent protein)into HeLa cells. Methods The DNA fragments encoding LFn and EGFP were amplified,respectively,and cloned into the plasmid pET-21 a(+)one after another to construct a recombinant plasmid pET-LFn-EGFP. The plasmid was txansformed into BL21 cells to express LFn-EGFP protein under the induction of IPTG. The protein was purified by Ni chelating chromatography. After incubation with LFn-EGFP in the presence of PA or not, the HeLa cells were analyzed by flow cytometry or laser confocal microscopy. Results The fusion protein LFn-EGFP was purified by over 90% homogeneity and retained the ability of LF to bind with PA when incubated with J774A.1 macrophage cells,and could get into HeLa cells. Conclusion The LFn-EGFP could enter the HeLa cells in a PA independent pathway. But PA could help more LFn-EGFP molecules enter into HeLa cells.