Effects of expanded frontal-parietal pedicled flap in reconstructing cervical scar contracture deformity in children after burns / 中华烧伤杂志

Objective: To explore the effects of expanded frontal-parietal pedicled flap in reconstructing cervical scar contracture deformity in children after burns. Methods: A retrospective observational study was conducted. From January 2015 to December 2020, 18 male children with cervical scar contracture deformity after burns who met the inclusion criteria were admitted to Zhengzhou First People's Hospital, aged 4 to 12 years, including 10 cases with degree Ⅱ cervical scar contracture deformity and 8 cases with degree Ⅲ scar contracture deformity, and were all reconstructed with expanded frontal-parietal pedicled flap. The surgery was performed in 3 stages. In the first stage, a cylindrical skin and soft tissue expander (hereinafter referred to as expander) with rated capacity of 300 to 500 mL was placed in the frontal-parietal region. The expansion time was 4 to 6 months with the total normal saline injection volume being 2.1 to 3.0 times of the rated capacity of expander. In the second stage, expander removal, scar excision, contracture release, and flap transfer were performed, with the flap areas of 18 cm×9 cm to 23 cm×13 cm and the secondary wound areas of 16 cm×8 cm to 21 cm×11 cm after scar excision and contracture release. After 3 to 4 weeks, in the third stage, the flap pedicle was cut off and restored. The rated volume of placed expander, total normal saline injection volume, type of vascular pedicle of flap, survival of flap and reconstruction of scar after the second stage surgery were recorded. The neck range of motion and cervico-mental angle were measured before surgery and one-year after surgery. The appearance of neck, occurrence of common complications in the donor and recipient sites of children, and satisfaction of children's families for treatment effects were followed up. Data were statistically analyzed with paired sample t test. Results: All the patients successfully completed the three stages of operation. The rated volume of implanted expander was 300 mL in 6 children, 400 mL in 9 children, and 500 mL in 3 children, with the volume of normal saline injection being 630 to 1 500 mL. The type of vascular pedicle of flap was double pedicle in 13 cases and was single pedicle in 5 cases. All the flaps in 17 children survived well, and the secondary wounds after neck scar excision and contracture release were all reconstructed in one procedure. In one case, the distal blood supply of the single pedicled flap was poor after the second stage surgery, with necrosis of about 2.5 cm in length. The distal necrotic tissue was removed on 10 days after the operation, and the wound was completely closed after the flap was repositioned. In the follow-up of 6 months to 3 years post operation, the cervical scar contracture deformity in 18 children was corrected without recurrence. The flap was not bloated, the texture was soft, and the appearances of chin and neck were good. The range of motion of cervical pre-buckling, extension, left flexion, and right flexion, and cervico-mental angle in one year after operation were improved compared with those before operation (with t values of 43.10, 22.64, 27.96, 20.59, and 88.42, respectively, P<0.01). The incision in the frontal donor site was located in the hairline, the scar was slight and concealed. No complication such as cranial depression was observed in expander placement site, and the children's families were satisfied with the result of reconstruction. Conclusions: Application of expanded frontal-parietal pedicled flap in reconstructing the cervical scar contracture deformity in children after burns can obviously improve the appearance and function of neck, with unlikely recurrence of postoperative scar contractures, thus it is an ideal method of reconstruction.

Immune response of HBsAg gene-modified dendritic cell-based vaccine in HepG2. 2. 15 hepatocellular carcinoma cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the cytotoxic T lymphocyte (CTL) response induced by dendritic cells (DC) transduced with recombinant adenovirus vector bearing hepatitis B virus surface antigen (HBsAg) gene in hepatocellular carcinoma HepG2. 2. 15 cells in vitro.</p><p><b>METHODS</b>Full length HBsAg cDNAs were subcloned into pIND vector, followed by being cloned into pShuttle vector. The HBsAg gene fragments resulted from the pShuttle-S digested with PI-Sce and I-Ceu were linked to the linear adeno-X virus DNA. After packaged with HEK293 cells, the adenovirus expression vector was obtained. Then the recombinant adenovirus expression plasmid AdVHBsAg was transfected into human monocyte-derived dendritic cells, to construct AdVHBsAg hepatocarcinoma tumor vaccine. The effectiveness of transfection was detected by Western blot. Surface molecules of AdVHBsAg-DC were detected by FACS. Autologous T cell proliferation stimulated by AdVHBsAg-DC was detected by 3H-TdR assay. Cytotoxic CTL activity induced by AdVHBsAg-DC in vitro was detected by LDH assay.</p><p><b>RESULTS</b>HBsAg gene in the inserted DNA of AdVHBsAg was confirmed by PCR, and predictive fragments proved by restriction enzyme digestion analysis were exhibited. Cell pathological changes appear after 10 days HEK293 cells transfected AdVHBsAg. Western blot analysis showed that HBV surface antigen gene was expressed in transfected DC, indicating that the transfection was effective. AdVHBsAg-DC was able to upregulate CD1a, CD11c, CD80, CD86 and HLA-DR. Autologus T cell proliferation induced by AdVHBsAg-DCs was significantly higher than that in DC control group and LacZ-DC group (P < 0.05). AdVHBsAg-DC activated CTL presented the specific killer ability to the hepatocellular carcinoma cells expressing HBsAg.</p><p><b>CONCLUSION</b>DC transduced with recombinant adenovirus HBsAg can express HBV-related hepatocellular carcinoma antigen (HBsAg), and AdVHBsAg-DC can induce potent immune response against HBsAg-positive hepatocellular carcinoma cells in vitro.</p>

Effect of vacuum-assisted closure on the expression of urokinase-type plasminogen activator and urokinase-type plasminogen activator receptor in acute and chronic wounds healing / 中华整形外科杂志

<p><b>OBJECTIVE</b>To study the effect of vacuum-assisted closure (V.A.C) on the expression of Urokinase-type plasminogen activator (uPA) and Urokinase-type plasminogen activator receptor(uPAR) protein in margin tissue of pigs with acute wounds and patients with chronic wounds.</p><p><b>METHODS</b>Acute wounds were created on the two side of five male pigs' back, the experiment wounds on one side received V. A. C treatment and the control side received traditional treatment. Punch biopsies were taken from margin tissue of the wounds in 0, 1, 3, 6, 9, 12, 18, 25 days after the V.A.C treatment. The uPA and uPAR positive cells were stained with immunohistochemical technique . Six human chronic wounds were also treated with the V. A. C treatment, and the samples of extravasate from those wounds were collected in 0, 1, 3, 5, 7 days after the treatment, and the levels of uPA and uPAR expression were examined by enzyme-linked immunosorbent assay (ELISA).</p><p><b>RESULTS</b>The expression of uPA and uPAR protein in margin tissues of pigs with acute wounds increased and peaked in 3 days after the treatment with V. A. C, then it presented rapidly downtrend, but the expression and staining in the experiment group were obviously higher than that of the control group. In the six chronic wounds, the high level expression of uPA and uPAR protein was decreased after the treatment with V. A. C.</p><p><b>CONCLUSION</b>The V. A. C may increase the expression of uPA and uPAR protein in acute wound keratinocytes and decrease the high expression of uPA and uPAR in chronic wounds.</p>

Effect of vacuum-assisted closure on the expression of proto-oncogenes and its significance during wound healing / 中华整形外科杂志

<p><b>OBJECTIVE</b>To study the effects of VAC on starting the process of wound healing and decreasing apoptosis.</p><p><b>METHODS</b>To examine the variations in expression of proto-oncogenes c-myc, c-jun and Bcl-2 in pig wound model with acute full-thickness skin defect and human chronic wounds by immunohistochemistry, calculate the numbers of expressive positive cells and the labelling index (LI), and observe the process of wound healing.</p><p><b>RESULTS</b>(1) In pig experiment, the wound in experimental group was very clean and without obvious exudates, many neoepiderm and granulation tissue rapidly appeared or formed after 6 days, and healed completely by the 25th day. On the contrary, in the wound of control group, more exudates and blood crust could be seen and fewer neoepiderm and granulation tissue appeared after 6 days and was healed by 30th day. Immediately after the wound was created, the expression of c-myc, c-jun and Bcl-2 was lower and mainly situated in nucleus or cytoplasma of the basilar cells. After the wound was created in control group, or after starting the VAC treatment in experimental group, their expression rapidly and obviously increased, the distribution of the positive cells also became enlarged, but the amount of expression decreased rapidly after the expressive peak have reached. In the successive 12 days following the wound was created, the expression of c-myc, c-jun and Bcl-2 in the experimental group was constantly higher than that of the control group. (2) In human chronic wounds, there wasn't obvious secretions and more healthy granulation tissue was rapidly formed after VAC treatment. The expression of c-jun was mainly located in cytoplasma of basilar cells of epithelium, dermal fibroblasts and inflammatory cells, and the positive cell and labelling index obviously decreased. The expression of c-myc and Bcl-2 was mainly in cytoplasma of basilar cells, but the amount of expression and the labelling index became obviously increased after VAC treatment.</p><p><b>CONCLUSIONS</b>VAC could rapidly start the healing course of the pig' s acute skin wound and human chronic wound, decrease apoptosis of the reparative cells, so as to accelerate wound healing.</p>

Influence of vacuum-assisted closure technique on expression of Bcl-2 and NGF/NGFmRNA during wound healing / 中华整形外科杂志

<p><b>OBJECTIVE</b>To explore the influence of vacuum-assisted closure technique (VAC) on expression of Bcl-2 and NGF during wound healing.</p><p><b>METHODS</b>Eighty Sprague-Dawley rats were randomly divided into 4 groups with 20 rats of each. Group T was the experimental group; group C1, C2 and C3 were the control groups. In group T and group C1, capsaicin was injected subcutaneously to the back of the rats to destroy the sensory nerve. VAC was employed to the wound of the rats in group T and C2 three times a day at 80 mmHg negative pressure. In all the groups, tissue samples were taken from the wound edge and granulation at 1, 3, 6, 9 and 12 days after the injury. Immunohistochemistry and in situ hybridization were used to detect the expression of Bcl-2 and NGF/NGFmRNA in the samples.</p><p><b>RESULTS</b>In group C2 and C3, the expression of Bcl-2 and NGF/NGFmRNA was obvious, which increased gradually and reached the peak at the 9th day. In the process of wound healing, the expression Bcl-2 and NGF/NGFmRNA was higher in the group C2 than in group C3 (P < 0.05). The expression Bcl-2 and NGF/NGFmRNA in group T and C1 was lower than group C2 and C3 (P < 0.05).</p><p><b>CONCLUSION</b>The application of the vacuum-assisted closure technique during wound healing increases the expression of the apoptosic modulation related protein Bcl-2 and affects the expression of NGF/NGFmRNA, which may promote the wound healing process.</p>