TLR2 affects CD86 expression and inflammatory response in burn injury mice through regulation of p38.

The aim of this study was to assess the effects of TLR2-p38-CD86 signaling pathways on the inflammatory response in a mouse model of burn injury. Wild-type (TLR2+/+) and mutant-type (TLR2-/-) mice were obtained, and a mouse burn injury model was constructed. Tissue samples were examined with hematoxylin and eosin staining and the transferase mediated nick end labeling (TUNEL) method. Macrophages were treated with TLR2 agonist and p38 inhibitor. The expression levels of TLR2, p38, CD86, IL-1ß, and TNF-α were quantified by RT-qPCR, Western blot, and ELISA. When compared with the sham group, the burn group had a significantly higher rate of apoptosis as well as higher expressions of TLR2, p38, CD86, IL-1ß, and TNF-α. Inhibiting TLR2 was shown to significantly reduce the expressions of p-p38, CD86, IL-1ß, and TNF-α. In the results of in-vitro experiments, TLR2 agonist increased the expression of p-p38, CD86, IL-1ß, and TNF-α, whereas a p38 inhibitor was shown to reduce the expression of CD86, IL-1ß, and TNF-α. Our results suggest that the TLR2-p38-CD86 signaling pathway plays a vital role in inflammation associated with burn injury.

[Effect of botulinum toxin type A on excessive expansion of myocutaneous flap].

OBJECTIVE: To investigate the effects of botulinum toxin type A (BTXA) on the excessive expansion speed and blood supply of myocutaneous flap. METHODS: Seven adult Guizhou minipigs of clean grade were included, female or male and weighing 16-20 kg. The 2.4 mL BTXA solution (96 U) was injected in cutaneous muscle (24 points) of one side as experimental group (n = 7), the 2.4 mL saline in the other side as control group (n = 7). Two expanders (200 mL) were implanted beneath the cutaneous muscle on the bilateral flank of each pig symmetrically at 3 days after injection. One week later, the expanders were filled with saline every 4 days with an intracapsular pressure of 11.97 kPa, and accumulative total amounted to 400 mL for 3 weeks in control group and 5 weeks in experimental group. Then the expanders were taken out; the myocutaneous flaps formed and were sutured in situ. The myocutaneous flaps were cut for histological examination and capillary count. The expansion speed of the myocutaneous flap were recorded. The blood supply of the myocutaneous flap were observed by infrared thermography at 1 week after implantation expanders, before removing the expanders, and at 5 days after myocutaneous flap suture in situ. RESULTS: All the animals survived to the end of the experiment. The total expansion time was (54.0 +/- 3.1) days in experimental group and (67.0 +/- 3.9) days in control group, showing significant difference (t = -8.107, P = 0.000). All myocutaneous flaps survived after being sutured in situ. Infrared thermograph revealed that the temperature of the distal myocutaneous flap in experimental group was significantly higher than that in control group at 1 week after implantation of expanders (P < 0.05); at 5 days after myocutaneous flap suture in situ, the temperature of the central flap in experimental group was significantly higher than that in control group (P < 0.05); and there was no significant difference between 2 groups at the other time points (P > 0.05). The histological observation showed that the blood vessel density of the dermal layer and tissue between the capsule and the muscle layer in experimental group was significantly higher than those in control group (P < 0.05). CONCLUSION: When excessive expansion is performed, BTXA can accelerate the expansion rate and improve the blood supply of expanded myocutaneous flaps.

[Effect of the botulinum toxin type A on myocutaneous flap expansion in minipigs model].

OBJECTIVE: To investigate the histologic effect of botulinum toxin type A (Botox A) injection on myocutaneous flap expansion in minipigs model. METHODS: Seven minipigs were included in this study. Two symmetric tattoo area, 10 cm x 6 cm in size, were selected on the bilateral flank of the pigs. The Botox A was injected into one tattoo area randomly, 4 U every point, 2 cm apart, with a total dose of 96 U. The same dose of sterile normal saline (0.9%) was injected in the same fashion on the opposite side as control. 3 days after injection , two 200 ml expanders were inserted beneath the cutaneous muscle at the tattoo area. After complete expansion of 200 ml, the specimens were drawn from both groups symmetrically and were stained by means of HE and Masson. The histologic changes of myocutaneous flap were compared. Thickness of each layer in myocutaneous flap was measured in histological section. RESULTS: The thickness of cutaneous muscle, capsule, dermis were (275.74 +/- 28.93) microm, (468.03 +/- 34.28) microm, (1990.79 +/- 102.10) microm in Botox group, and (409.13 +/- 44.63) microm, (626.55 +/- 44.05) microm, (2508.44 +/- 70.71) microm in saline group, respectively, show a significant difference between the two groups (P < 0.01). The Masson stained slice showed that collagen average gray of capsule in Botox group was 185.38 +/- 9.56, which was significantly higher than that in the saline group (120.77 +/- 10.31, P < 0.01). Light microscope (HE stained sections ) showed that muscle in Botox group was significantly atrophy and cross-section of muscle fiber decreased. The muscle fiber in saline group was generally normal. It was observed through transmission electron microscope that the light and dark band of muscle cell became fuzzy and the Z line bending in Botox group. The light and dark band in saline group arranged neatly, the Z line was clear. CONCLUSIONS: Application of Botox A in myocutaneous flap expansion can make the muscle atrophy and reduce the content of collagen in capsule layer, making the myocutaneous flap thinner which is suitable for reconstruction in face and neck.

[Clinical application of autologous buccal micro-mucosa graft in vaginal reconstruction].

UNLABELLED: OBJECTIVE To investigate the effect of vaginal reconstruction with autologous buccal micro-mucosa graft. METHODS: From March 2007 and April 2008, 10 patients with absence of vagina were treated, aged 18-31 years (mean 26 years). Nine of them were congenital absence of vagina, and the remaining one was vaginal stenosis after vaginal reconstruction. They all exhibited normal secondary sexual characteristics, normal hormonal levels and 46, XX karyotype. Their abdominal ultrasonography revealed the normal ovaries and tubes but absence of the uterus or small rudimentary horns. However the one with vaginal stenosis had normal uterus. The buccal mucosa graft was minced into 0.5 mm in size and was transplanted to the cavity which was dissected between the bladder and the rectum. RESULTS: The operation was performed successfully in all cases. The operative time was about 1-2 hours and operative blood loss was 80-100 mL. Postoperative complication occurred in only one case for vaginal bleeding. The patient recovered and the wound healed well after immediate management. The others healed primarily without any complications. All cases were followed up for 4-16 months. The depth of neovagina which was formed was 6-10 cm and the width was about two fingers. The lining was pink-colored and smooth, and was confirmed as nonkeratinizing squamous stratified mucosa by histopathological examination. The donor sites healed uneventfully with no change in mouth opening. The perineal area was not disturbed. Four patients were married and satisfied with their sexual life without pain and bleeding. CONCLUSION: Vaginal reconstruction with autologous buccal micro-mucosa graft is an easy, minimally invasive and useful method.

[Repair of hypospadias using scrotal septum vascular pedicle flap with two wing-like split-thickness skin graft].

OBJECTIVE: To investigate the effect of scrotal septum vascular pedicle flap with two wing-like split-thickness skin graft in reconstructing urethra in patients with hypospadias and in reducing the complications. METHODS: From January 2007 to March 2008, 30 cases of hypospadias were treated, with a median age of 10 years (2-20 years). There were 13 cases of proximal shaft type, 12 cases of penoscrotal type and 5 cases of scrotal type. There were 8 cases with operation history. The flap size ranged from 4.0 cm x 0.8 cm to 9.0 cm x 1.0 cm and 5 mm with two wing-like split-thickness skin graft. When the downward curvature corrected, length of the flap could be determined by the length of the urethra that needed to be reconstructed. RESULTS: All flaps survived. The incision healed by first intention in all patients except one whose incision healed after change dressing because of frequent erection. Incision at donor site healed well. Eighteen patients were followed up for 6-12 months, including 8 with second operation history. The reconstructed urethras were unobstructed and no urethrostenosis or urinary fistula happened. CONCLUSION: This is an improved technique of the scrotal septum flap in urethra reconstruction. It takes advantages of both flap and split-thickness skin graft in reconstructing urethra and avoids the disadvantages of a single tissue. It is a good choice for treating hypospadias whose urinary meatus locates neighborly to penoscrotal junctional zone.

[Experimental study on early escharectomy after major burns in minipigs].

OBJECTIVE: To investigate optimal time for early escharectomy after severe scald in minipigs. METHODS: Minipigs inflicted with 35% TBSA full thickness burn were employed in the study, and they were randomly divided into A (n = 7, with escharectomy at 6PSH), and B (n = 7, with escharectomy at 24 PSH) groups. The hemodynamics indices, hemorrheology, and the serum levels of cytokines in the two groups were determined before burns and at 6, 8, 16, 24 and 72PSH. RESULTS: The hemodynamics indices in A group obviously improved compared with those in B group. The cardiac output (CO, 2.28 +/- 0.03 L/min) and right arterial pressure (RAP, 4.54 +/- 0.04 mmHg) in A group recovered to the pre-injury levels at 48 PSH. There was no difference of the hemorrheology indices between the two groups (P > 0.05). The serum contents of cytokines in A group declined to the pre-injury level on 1 PBW, while those in B group were significantly higher than those before injury and those in A group (P < 0.05 or P > 0.01). CONCLUSION: Escharectomy during 6 PBH might be safe and feasible, thus preventing long-term complications effectively.