Peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist inhibits collagen synthesis in human hypertrophic scar fibroblasts by targeting Smad3 via miR-145.

The transcription factor peroxisome proliferator-activated receptor-γ (PPAR-γ) functions to regulate cell differentiation and lipid metabolism. Recently, its agonist has been documented to regulate extracellular matrix production in human dermal fibroblasts. This study explored the underlying molecular mechanisms and gene interactions in hypertrophic scar fibroblasts (HSFBs) in vitro. HSFBs were cultured and treated with or without PPAR-γ agonist or antagonist for gene expression. Bioinformatical analysis predicted that miR-145 could target Smad3 expression. Luciferase assay was used to confirm such an interaction. The data showed that PPAR-γ agonist troglitazone suppressed expression of Smad3 and Col1 in HSFBs. PPAR-γ agonist induced miR-145 at the gene transcriptional level, which in turn inhibited Smad3 expression and Col1 level in HSFBs. Furthermore, ELISA data showed that Col1 level in HSFBs was controlled by a feedback regulation mechanism involved in PPAR-γ agonist and antagonist-regulated expression of miR-145 and Smad3 in HSFBs. These findings indicate that PPAR-γ-miR-145-Smad3 axis plays a role in regulation of collagen synthesis in HSFBs.

Inhibition of Notch signaling leads to increased intracellular ROS by up-regulating Nox4 expression in primary HUVECs.

The essential roles of Notch pathway in angiogenesis have been reported for years. However, how Notch pathway plays its role in regulating endothelial cells remains largely unknown. In this study we found that blockade of Notch signaling with a γ-secretase inhibitor increased reactive oxygen species (ROS) in primary human umbilical vein endothelial cells (HUVECs) under both normaxic and ischemia/reperfusion (I/R) conditions. Abruption of ROS generation with ROS scavengers or specific inhibitors of ROS production in HUVECs abolished Notch blockade-induced HUVEC proliferation, migration and adhesion, suggesting that the regulation of Notch pathway on endothelial cell behavior is at least partially dependent on its down-regulation of ROS level. We further showed that the enhanced generation of ROS after blocking Notch signal was accompanied by augmented expression of Nox4, which led to increased phosphorylation of VEGFR2 and ERK in HUVECs. In summary, our results have shown that Notch signaling regulates ROS generation by suppressing Nox4, and further modulates endothelial cell proliferation, migration and adhesion.

[Systemic therapy for defects of skin and soft tissue on the knees after severe trauma or burn].

OBJECTIVE: To explore the methods of systemic treatment of defects of skin and soft tissue on the knees after severe trauma or burn. METHODS: Twenty patients with defects of skin and soft tissue on the knees after severe trauma or burn hospitalized in our center from January 2009 to December 2011. The injury areas on the knees ranged from 5 cm×4 cm to 30 cm×20 cm. The wounds were treated with radical debridement, vacuum sealing drainage, and douche through dripping to control infection in early stage. Then they were covered with transplantation of skin grafts plus flap or only with flap. Totally 8 local flaps (including 6 local rotation or transposition flaps and 2 saphenous artery flaps) and 12 free flaps (including 8 anterolateral thigh flaps and 4 latissimus dorsi musculocutaneous flaps) were used. The flap size ranged from 6 cm×5 cm to 32 cm×22 cm. The rehabilitation training of the knee joints was carried out in the early stage after wound healing. RESULTS: All free skin grafts and flaps used in 15 patients survived. Thirteen of them were primarily healed, while some small parts of skin grafts of the other two patients were in poor condition because of infection, and they healed after another session of skin transplantation. Infection occurred under the free flap in one of the 5 patients transplanted with flaps only, which was healed after continuous douche through dripping and another surgical debridement following wet dressing. The knee joints were in good function during the follow-up period of 1 - 3 years. CONCLUSIONS: The systemic therapy of radical debridement, vacuum sealing drainage technique, douche through dripping, transplantation of large autologous grafts and flaps, and the early rehabilitation training are effective and reliable in repairing defects of skin and soft tissue at the knee region after severe injuries.

Effect of nonpeptide NK1 receptor antagonist L-703,606 on the edema formation in rats at early stage after deep partial-thickness skin scalding.

OBJECTIVE: To investigate the effect and the relevant potential mechanism of nonpeptide neurokinin 1 (NK1) receptor antagonist L-703,606 in the edema formation after burn injury. METHOD: L-703,606 treatment was performed in Sprague-Dawley (SD) rats at early stage after deep partial-thickness skin scalding. One hundred and fifty two adult male SD rats were used in the study and randomly divided into sham scald (SS, n=8), scald control (SC, n=48), and L-703,606 treatment (LT, n=48) groups. The rats in SC and LT groups were subjected to 20% total body surface area (TBSA) deep partial-thickness skin scalding. Modified Evans blue extravasation, tracing electron microscopy by lanthanum nitrate and mean water content assay were employed to observe and detect the changes of vascular permeability, ultrastructure and edema formation in adjacent tissue to the wounds and in the jejuna of rats at early stage (72 h) after scald. RESULTS: The pathological increase of vascular permeability in the periwound tissue and jejunum of rats in LT group were significantly lower than that in SC group (P<0.01), and recuperated earlier. Meanwhile, the changes of water contents of corresponding tissues in LT group were lighter than those in SC group (P<0.01). The ultrastructural changes of the microvessels in the peri-wound tissue of LT group showed that the junctions between microvascular endothelium cells were more narrow than those of SC group, moreover, and the number of opening and the engorgement and cavitation of the vascular endothelium cells decreased, the areosis and edema in perivascular tissue lightened, and the precipitation of the high eletron density lanthanum tracing agent in the interspace of the tissue decreased significantly in LT group. CONCLUSIONS: It is concluded that nonpeptide NK1-receptor antagonist L-703,606 could lighten the vascular permeability and edema formation in the periwound tissue and jejunum, and accelerate the normalization process of pathological changes in the tissues of rats after scald.

Protection against TGF-ß1-induced fibrosis effects of IL-10 on dermal fibroblasts and its potential therapeutics for the reduction of skin scarring.

Scarring, tightly associated with fibrosis, is a significant symptomatic clinical problem. Interleukin 10 (IL-10) has been identified as a candidate scar-improving therapy based on preclinical studies. However, the molecular mechanism of IL-10 in scar improvement is still uncertain. In this study, human dermal fibroblasts stimulated with TGF-ß1 were treated with IL-10 to analyze the mRNA and some of proteins' expression levels of type I collagen (Col1), type III collagen (Col3), alpha-smooth muscle actin (α-SMA), matrix metalloproteinase-1 (MMP1), MMP2, MMP8 and tissue inhibitor of metalloproteinase 1 (TIMP1), TIMP2 by real-time PCR and Western blot, to observe α-SMA-positive fibroblasts by immunocytochemistry. The contracture and improvement of fibroblast-populated collagen lattice (FPCL) and a murine model of wound healing were used to evaluate the scar-improving effects by histological staining. The results showed that IL-10 can significantly down-regulate the mRNA and protein expression levels of Col1, Col3, α-SMA, and up-regulate the mRNA expression levels of MMP1 and MMP8, and decrease α-SMA-positive fibroblasts. FPCL analysis showed that the IL-10 (20 ng/ml) can significantly inhibit the contracture, improve the architecture of FPCL. Wounds injected with IL-10 demonstrated that the appearance of scar was improved, the wound margin of scarring was narrow, and the deposition of collagens (Col1 and Col3) in regenerated tissue was relieved. These results provide direct evidences that IL-10 has the inhibitory effects on the excessive deposition of extracellular matrix components and fibroblast-to-myofibroblast transition, and show that IL-10 has the potential therapy in prevention and reduction of skin scarring.

Reduced expression of microtubule-associated protein 1 light chain 3 in hypertrophic scars.

Autophagy is a tightly regulated physiological process essential for cellular maintenance, differentiation, development, and homeostasis. Aberration of this process associates with the pathogeneses of several diseases in mammals. Hypertrophic scar (HS) is characterized by an abundance of collagenous tissue with hypercellularity. However, the molecular mechanism in HS formation is poorly understood. We compared the autophagic capacity in HS and its normal skin (NS) counterparts and explored the molecular mechanism of autophagy during the formation of HS. Microtubule-associated protein 1 light chain 3 (LC3) proteins in HS and NS were detected by immunohistochemistry, Western blot and quantitative real-time PCR (qPCR). The data showed that LC3 positive staining in HS was less intensive relative to NS group (p < 0.05). Three forms of LC3, with molecular weights of about 19 kDa (proLC3), 18 kDa (LC3-I) and 16 kDa (LC3-II), respectively, expressed in NS by Western blot. In contrast, only proLC3 expressed while both LC3-I and LC3-II were significantly downregulated in HS. The protein level of beclin 1 in HS was significantly lower compared with NS (p < 0.05). LC3 and beclin 1 mRNA levels in HS were significantly lower than that in NS (p < 0.05). These results suggest that the generation of LC3-I and LC3-II are interrupted in HS, and that the resultant decrease of autophagic capacity may associate with the pathogenesis of HS.

[Repair of extensive deep burn wounds in late stage with free muscle flap].

OBJECTIVE: To explore the means for the reconstruction of extensive deep burn wounds with exposure of bone and joint in late stage. METHODS: Among all the patients with extensive deep burn hospitalized between January 2009 and May 2011, 5 patients presented wounds with exposure of bone and joint in the late stage of treatment that could not be covered by free skin grafts or flaps. Two of the five patients had more than 2 and the other 3 patients had only one such wound(s). The wound size ranged from 8 cm×5 cm to 21 cm×8 cm. Wounds were repaired by transplantation of 7 free muscle flaps (including 4 free rectus abdominis flaps and 3 latissimus dorsi flaps) combined with split-thickness skin grafts harvested from scalp. RESULTS: All the muscle flaps and skin grafts survived. Wounds with bone and joint exposure healed well. At one-year follow-up of some patients, good appearance of repaired areas and normal function of joints were observed with no signs of ulceration, arthritis, or osteomyelitis. CONCLUSIONS: Transplantation of free muscle flaps combined with split-thickness skin grafts harvested from the scalp provides satisfactory reconstruction for wounds with deep tissue exposure in patients with a shortage of skin donor site.

Insulin-mediated inhibition of p38 mitogen-activated protein kinase protects cardiomyocytes in severe burns.

Thermal injury inhibits Akt activation and upregulates p38 mitogen-activated protein kinase, which in turn induces inflammation and increases apoptosis. This study aimed to elucidate the mechanism underlying the cytoprotective role of insulin in severe burns by examining the effects of insulin on inflammation and apoptosis mediated by p38 mitogen-activated protein kinase in burn serum-challenged cardiomyocytes. Neonatal rat cardiomyocytes were exposed to burn serum for 6 hours in the presence or absence of insulin and pretreated with inhibitors to p38 mitogen-activated protein kinase (SB203580) and Akt (LY294002). The authors examined expression of myocardial tumor necrosis factor-alpha, cardiac myofilament proteins caspase-3 and Bcl2, and apoptosis. Burn serum-induced upregulation of tumor necrosis factor was inhibited by both SB203580 and insulin. LY294002 reversed insulin-mediated downregulation of tumor necrosis factor. Both SB203580 and insulin inhibited apoptosis, resulting in fewer pyknotic nuclei and inhibition of caspase-3 activation and Bcl2 downregulation. LY294002 reversed insulin-mediated inhibition of apoptosis. Insulin decreases inflammatory cytokine expression and apoptosis via PI3K/Akt-mediated inhibition of p38 mitogen-activated protein kinase. The cytoprotective role of insulin suggests that it may have a potential role in strategies for treating thermal injuries.

Intensive insulin treatment attenuates burn-initiated acute lung injury in rats: role of the protective endothelium.

Nonmetabolic effects of intensive insulin therapy in critically ill patients have been reported, but the underlying mechanisms are unclear. This study was designed to test the hypothesis that intensive insulin treatment would attenuate burn-induced acute lung injury by protecting the pulmonary microvascular endothelium. The rat model of burn injury was achieved by exposure to 92°C water for 18 seconds. The rats were randomly allocated into the sham, burn/normal saline (NS), and burn/intensive insulin treatment groups. Blood glucose level was maintained between 5 and 7 mmol/L in rats in the burn/intensive insulin treatment group. Pulmonary injury was assessed by hematoxylin and eosin staining, scanning electron microscopy, bronchoalveolar lavage fluid protein concentrations, the lung wet:dry weight ratio, and lung myeloperoxidase activity. Pulmonary microvascular endothelial cells were examined by transmission electron microscopy. Western blotting was used to determine the protein expression of caspase-3. Intensive insulin treatment markedly attenuated the acute lung injury, revealed by improvements in histological features and significant decreases in bronchoalveolar lavage fluid protein concentrations, pulmonary wet:dry weight ratio, and myeloperoxidase activity at 12 hours after injury (P < .05 or P < .01 vs burn/NS). Moreover, the injured pulmonary microvascular endothelial cells showed significant improvements, whereas caspase-3 was markedly downregulated in the burn/intensive insulin treatment group when compared with the burn/NS group. Overall, intensive insulin treatment efficiently attenuated pulmonary microvascular endothelial cell dysfunction, decreased cell apoptosis, and inhibited acute lung injury after a burn. These findings may be useful in preventing organ failure after burn injury.

[Repair of devastating wounds with free composite tissue flap].

OBJECTIVE: To study the safety and effects of free composite tissue flaps in repairing devastating wounds in early stage. METHODS: One hundred and twenty-three patients with 128 devastating wounds hospitalized in our burns center from 2005 to 2009 were repaired with free flaps or composite tissue flaps. Flap types used included 58 latissimus dorsi muscular flaps, 32 anterolateral thigh flaps, 21 circumflex scapular flaps, 6 dorsalis pedis composite flaps, 3 big toe nail skin flaps, 3 forearm flaps, and 1 lateral thoracic flap. One wound was repaired with lateral lower leg flap with fibula, and 3 wounds with free latissimus dorsi muscular flap plus skin graft. RESULTS: Vascular crisis was observed in 10 transplanted flaps 1 to 5 days after operation; 6 flaps with this complication were saved after emergency surgical exploration. Total survival rate of transplanted flaps and composite tissue flaps was 95.3% (122/128). All patients were followed up for 3 months to 4 years; satisfactory appearance and restoration of partial function were found in all of them. CONCLUSIONS: Free composite tissue transplantation reduces amputation rate, achieves primary reconstruction of function with good appearance, shortens length of hospital stay, and reduces surgical operation time, complications, and treatment cost. It is a good approach in the repair of massive devastating soft tissue injury.

[Microsurgical repair of skin and soft tissue defects on head, face, and neck].

OBJECTIVE: To study the microsurgical method of repairing skin and soft tissue defects on head, face, and neck. METHODS: Thirty-one patients with skin and soft tissue defects on the head, face, or neck were hospitalized from July 2007 to May 2010, including 10 cases of scalp defects, 4 cases of skin and soft tissue defects on face, and 17 cases of skin and soft tissue defects on neck. Among them, the cause in 20 cases was trauma, and in 11 cases they were secondary to release of cicatricial contraction. Free flaps were transplanted to repair the wounds, including 13 latissimus dorsi flaps, 3 lateral thoracic flaps, 5 scapular flaps, and 10 anterolateral thigh flaps. The area of flaps ranged from 8 cm × 5 cm to 25 cm × 18 cm. RESULTS: All flaps survived, and all the wounds healed by first intention. The average length of hospital stay was 16.7 days. Twenty-eight patients were followed up for 2 months, and in all of them satisfactory function and appearance were restored. CONCLUSIONS: Free flap graft based on microsurgery can repair wound of skin and soft tissue defects on head, face and neck by a single operation, which eases suffering of patients, and shortens the length of hospital stay.

[Effect of heat injured keratinocytes supernatant on biological behavior of fibroblasts].

OBJECTIVE: To observe the effect of the supernatant of heat injured keratinocytes (KC) on biological behavior of the dermal fibroblasts (Fb). METHODS: Human dermal Fb were isolated and cultured. A model of heat injured KC (HaCaT) was reproduced in vitro. Supernatant of normal KC and the supernatant of KC culture 12 hours after heat injury were collected and diluted with non-serum DMEM in 1:1 volume ratio to make normal KC conditioned medium (NKCM) and heat injury KC conditioned medium (HKCM) respectively. Fb was respectively treated with non-serum DMEM and 2 kinds of conditioned medium. (1) The proliferation of Fb was detected with MTT method at post culture hour (PCH) 12, 24, 36, 48. (2) The apoptosis of Fb was determined by flow cytometry at PCH 12 (Fb were heat injured in advance; Fb without heat treatment was used as control). (3) At PCH 24, expression of a-SMA in Fb cytoplasm was determined with immunofluorescence method; expression of a-SMA mRNA in Fb was determined with real-time quantified PCR. Data were processed with one-way analysis of variance, and pairwise comparison among groups with LSD-t test. RESULTS: (1) The proliferation of Fb: the absorbance value of Fb cultured with HKCM at PCH 12, 24, 36, 48 was respectively higher than that of Fb cultured with non-serum DMEM (with t value respectively 1.89, 2.35, 2.02, 1.94, and P values all below 0.01). There were significant statistical differences between the absorbance values of Fb cultured with HKCM and those of Fb cultured with NKCM at PCH 12, 24, and 48 (at PCH 12, t = 1.83, P < 0.01; at PCH 24, t = 2.91, P < 0.05; at PCH 48, t = 1.83, P < 0.05). (2) Apoptosis of Fb cultured with HKCM was diminished as compared with that of Fb cultured with NKCM and of Fb without treatment (t = 3.31, P < 0.05; t = 1.47, P < 0.01). (3) The expression of alpha-SMA (red fluorescence) in Fb cultured with non-serum DMEM or NKCM was less as seen under fluorescence scope, and it was obviously increased in Fb cultured with HKCM. (4) The relative expression amount of alpha-SMA mRNA in Fb cultured with HKCM was 1.32 +/- 0.06, which was higher than that both in Fb cultured with NKCM (1.14 +/- 0.07, t = 2.51, P < 0.05) and in Fb cultured with non-serum DMEM (1.00 +/- 0.09, t = 1.77, P < 0.05). CONCLUSIONS: The supernatant of KC 12 hours after heat injury can obviously promote the proliferation of Fb, inhibit its apoptosis and accelerate transdifferentiation of Fb to myofibroblasts.

[Inhibitory effect of insulin on nuclear factor-kappa B nuclear translocation of vascular endothelial cells induced by burn serum].

OBJECTIVE: To study the inhibitory effects of insulin on nuclear factor-kappa B (NF-kappaB) nuclear translocation of vascular endothelial cells induced by burn serum and its correlative mechanism. METHODS: Human umbilical vein endothelial cells (HUVECs) were cultured in vitro and divided into 5 groups: blank control group (BC, ordinary culture without any stimulation), normal serum control group (NS, cultured with nutrient solution containing 20% healthy human serum), burn serum stimulation group (BS, cultured with nutrient solution containing 20% burn human serum), burn serum+insulin treatment group (BI, cultured with nutrient solution containing 20% burn human serum and 1x10(-7) mol/L insulin), inhibitor pretreatment group [IP, pretreated with 50 micromol/L protein kinase B (Akt) specific inhibitor LY-294002, then cultured with the same medium as used in BI group 30 minutes later] according to the random number table. Six hours later, the injury and apoptosis of HUVECs was respectively observed by the scanning electron microscope and determined by the flow cytometry. Meanwhile, the phosphorylation of inhibitor kappa B-alpha (p-IkappaB-alpha) and Akt (p-Akt) in cytoplasm, and the content of NF-kappaB-p65 in nucleus were determined with Western blot. RESULTS: (1) Compared with those in BC group, HUVECs in BS group shrank obviously with irregular nuclear structure, and intercellular links jagged or vanished. Slight change was observed in HUVECs structure in NS and BI groups, with the cell ductility and nuclear structure much better than those in BS group. (2) The apoptosis rates of HUVECs in BS group [(28.5+/-2.3)%], BI group [(22.3+/-1.8)%], and IP group [(29.7+/-2.4)%] were all obviously higher than that in BC group [(15.7+/-2.2)%, F=14.288, P<0.05 or P<0.01]. There was no significant statistical difference between NS group [(17.0+/-2.5)%] and BC group in apoptosis rate (F=14.288, P>0.05). The apoptosis rate of HUVECs in BI group was obviously lower than that in BS group (F=14.288, P<0.05). (3) Compared with those in BC group, the protein expressions of p-IkappaB-alpha in cytoplasm and NF-kappaB-p65 in nucleus were up-regulated, and the protein expression of p-Akt in cytoplasm was down-regulated in BS and IP groups. The expression levels of the three proteins in NS and BI groups were close to those in BC group. CONCLUSIONS: Insulin could inhibit the IkappaB phosphorylation, and then restrict NF-kappaB nuclear translocation and improve the vascular endothelial cells function accordingly through regulating phosphatidylinositol 3 kinase/Akt pathway.

[Reproduction of a model of heat injured keratinocyte in vitro and observation on its apoptosis rate].

OBJECTIVE: To reproduce a model of heat injured KC in vitro and explore its apoptosis rate of KC due to heat injury at different temperature. METHODS: Human KCs were cultured in vitro, and they were incubated at 37, 41, 43, 45, 48, and 51 degrees C respectively for 10 mins in water bath. Trypan blue staining and Hoechst 33258 fluorescence staining were used respectively to determine necrosis and apoptosis of KC. Rates of apoptosis and necrosis of KC were analyzed quantitatively by flow cytometer. The proliferation activity of KC after heat injury was detected by MTT test. RESULTS: The results of trypan blue staining, Hoechst 33258 fluorescence staining, and flow cytometer demonstrated that number of apoptotic and necrotic KC increased gradually along with a rise of water bath temperature. The rates of apoptosis and necrosis of KC were respectively (12.3 +/- 3.2)% and (14.1 +/- 1.6)% at 45 degrees C, (27.7 +/- 5.1)% and (58.0 +/- 4.2)% at 48 degrees C. Rate of KC necrosis reached up to (83.0 +/- 5.3)% at 51 degrees C. Inhibition of KC growth reached a stationary phase when the injurious temperature reached 45 degrees C as observed with MTT test. CONCLUSIONS: Heat injury can induce apoptosis and growth inhibition of KC in vitro. Incubating KC at 45 degrees C for 10 mins is a good condition to reproduce a model of heat injured KC in vitro. This model may be used to study the biological character and apoptosis of KC after burn injury.

[Surgical therapy for massive deep skin and soft tissue injuries].

OBJECTIVE: To explore the methods of repair of massive deep skin and soft tissue injuries. METHODS: Fifty-six patients with deep skin and soft tissue injuries were hospitalized from July 2006 to January 2008. Among them, 23 cases were caused by burn, 17 cases by electric injury, 7 cases by hot crush injury, 6 cases by avulsion injury, and 3 cases due to other reasons (including traffic accident, crush injury, soft tissue infection respectively). Sixty-five skin flaps were raised to repair and reconstruct the injured tissues, including 21 local flaps, 18 distant pedicled skin flaps, and 26 free skin flaps. The area of skin flaps ranged from 1.5 cm x 1.0 cm to 39.0 cm x 23.0 cm. RESULTS: Sixty skin flaps survived completely, partial necrosis occurred in 3 flaps, and complete necrosis in 2 flaps. There was no obvious difference in average survival rate among local skin flaps (95.2%), distant pedicled skin flaps (88.8%), and free skin flaps (92.3%, P > 0.05). CONCLUSIONS: Skin flap transposition can be still considered as the major effective method in repair of massive deep skin and soft tissue injury. On the premises of high survival rate, free skin flap transposition can be considered as the first choice.

[A cost-effectiveness analysis of comprehensive rehabilitation treatment of hand burn].

OBJECTIVE: To observe the effect of comprehensive rehabilitation treatment on hand burn, and to make a cost-effectiveness analysis. METHODS: Sixty-two patients with ninety-eight affected hands were divided into rehabilitation group (32 cases, 48 hands) and control group (30 cases, 50 hands). Patients in rehabilitation group received comprehensive rehabilitation treatment at early stage after burn; patients in control group were given instructions for function training at the same time. The functions of the hands to be restored including grasp, hold, pinch, nip, forearm pronation and supination, fetching, laying, and writing abilities of patients in both groups were quantitatively evaluated with Carroll's upper extremity function test before treatment and 5 months after. Direct medical costs of patients in both groups within 5 months were respectively added up to make a cost-effectiveness analysis. RESULTS: In rehabilitation group, function of digital opposition, palmar opposition, holding, and pinching of 37 hands recovered well, with which patients could pick food, put on clothes, go to toilet, and self-care etc. independently. Function of digital opposition, palmar opposition, holding, pinching half recovered in 7 hands, accompanied with well recovered of metacarpophalangeal function, but recovery of function of interphalangeal joint was less satisfactory. Although patients could grasp and hold, they were still poor in fine and harmonized activities. Joint ranges of motion of 4 hands were poor with limited function, and this was resulted from not strictly following treatment for remaining granulation wound. In control group, 23 hands received reconstructive surgery, 14 of them recovered with good function, but were poor in most of fine and harmonized activities. Severe claw hands were found in 13 hands. The ratio between total mean cost value and total function increment value in rehabilitation group (181 +/- 11) was obviously lower than that in control group (298 +/- 30, P < 0.01). CONCLUSIONS: Comprehensive rehabilitation treatment at early stage after hand burn has a good effect on prevention and treatment of hand deformity, promoting recovery of hand function and improving hand appearance. It is also less costly.

[Study on crosstalk between phosphatidylinositol 3 -kinase/Akt pathway and p38 mitogen-activated protein kinase pathway in cardiomyocyte with challenge of burn serum].

OBJECTIVE: To investigate the possibility of crosstalk between phosphatidylinositol 3-kinase (PI3-K)/Akt pathway and p38 mitogen-activated protein kinase (p38MAPK) pathway in cardiomyocyte with challenge of burn serum, and to explore their influence on cardiomyocyte injury after burn. METHODS: The model of murine cardiomyocyte with stimulation of burn serum was established. (1) The level of Akt and p38 phosphorylation in cardiomyocyte were examined with stimulation of 10% burn serum before stimulation and 1, 3, 6, 12, 24 hour after stimulation. (2) The levels of Akt and p38 phosphorylation in cardiomyocyte were determined with stimulation of burn serum (at concentration of 5%, 10%, 20%) or 10% burn serum plus insulin (at concentration of 1 x 10(-8), 1 x 10(-7), 1 x 10(-6)mol/L). The content of creatine kinase (CK) in supernate was also detected. (3) Addition to the inhibitor of p38 MAPK pathway (SB203580) and PI3K/Akt pathway (LY294002), the level of p38MAPK, PI3K/Akt and the content of CK in supernate were determined. RESULTS: (1) The level of p-p38 in cardiomyocyte was 4.0 +/- 0.8, 3.6 +/- 0.8, 5.1 +/- 1.6, 2.4 +/- 0.5, 3.0 +/- 0.6 at 1, 3, 6, 12, 24 hour (s) after stimulation of burn serum, which was obviously higher than that immediate after stimulation (1.0, P < 0.01). The level of p-Akt was 0.15 +/- 0.07, 0.64 +/- 0.10, 0.26 +/- 0.08, 0.38 +/- 0.11, 0.59 +/- 0.13, which was obviously lower than that before stimulation (1.00, P < 0.01). (2) With stimulation of different concentration of burn serum or burn serum plus insulin, the level of p-Akt and p-p38 changed in the opposite directions comparatively. The content of CK increased along with increase of burn serum concentration, but decreased obviously with treatment of insulin (P < 0.05 or 0.01). (3) Low level of p38 induced by burn serum was increased after treatment of LY294002, which neutralized the protection of insulin (P < 0.01). Low level of p-Akt induced by burn serum increased after treatment of SB203580 (P < 0.01), which inhibited the release of CK induced by burn serum. CONCLUSION: There is being crosstalk between PI3K/Akt pathway and p38 MAPK pathway in cardiomyocytes with challenge of burn serum, which may regulate cardiomyocytes.

[Functional reconstruction of multiple severe deformities after extensive deep burn].

To explore new measures for functional reconstruction of multiple severe deformities as a result of extensive deep burn (total burn surface area > or = 90% TBSA, including deep burn > or = 70%TBSA) in late stage. Twelve severe burn patients with above-mentioned deformities were hospitalized in our ward during 1960--2005, the scars resulted from burns were distributed from head to foot with 173 deformities, including 27 scar ulcers. All patients lacked of self-care ability, among them some could not stand. Due to inadequate skin source, deformities were corrected by skin from matured scars expanded with subcutaneous balloon at late postburn stage. Following our former clinical experience, anatomic investigation and experimental research, we chose the following methods to correct deformities and restore functions: application of split-thickness scar skin after expansion (88 wounds); use of scar skin flap/scar-Achilles tendon flaps (59 wounds); combination of thin split-thickness skin grafts from scar and allogeneic acellular dermal matrix (composite skin, 40 wounds). All grafts survived, the appearance and function were improved obviously without complications. Follow-up 1-40 years, all patients could take care themselves with satisfactory function and appearance, and among them 8 patients returned to work (one had worked for 40 years), 2 patients married and had children. The above-mentioned measures are safe, reliable and effective for functional reconstruction of deformities.

[Effect of intensive insulin treatment on cardiac myocytes of severely scalded rats].

OBJECTIVE: To study the protective effect of intensive insulin treatment on cardiac myocytes of severely scalded rats. METHODS: Eighteen model Sprague-Dawley (SD) rats were subjected to 30% total body surface area (TBSA) full thickness injury, and they were divided into three groups with 6 rats in each group. The right jugular vein was cannulated for fluid resuscitation and administration of drugs. The rats in burn group were injected with normal saline, the intensive insulin group with injection of insulin to maintain plasma glucose content in normal range, and the sham burn group received physiologic dose of saline without burn injury. Plasma glucose was monitored after burn injury. Rats were sacrificed at 6 hours postburn to examine plasma myocardial enzymes spectrum as well as histological and ultrastructure changes in cardiac tissue. The expression of p-Akt was detected by western blotting. RESULTS: Plasma glucose level was significantly elevated in burn group within postburn 6 hours as compared with the sham burn group, and lowered in intensive insulin group (4.5 approximately 5.2 mmol/L vs. 7.6 approximately 8.4 mmol/L, P<0.05 or P<0.01). And the intensive insulin therapy could effectively inhibit the release of cardiac enzymes [lactate dehydrogenase (LDH): (2 369.3+/- 178.9) U/L vs. (2 684.1+/-335.0) U/L, P<0.05; alpha-hydroxybutyrate dehydrogenase (alpha-HBD): (576.7+/-219.2) U/L vs. (1 002.0+/-347.1) U/L, P<0.01; creatine kinase (CK): (1 041.9+/-623.2) U/L vs. (2 447.1+/-1 183.7) U/L, P<0.01]. The expression of p-Akt was significantly strengthened in the intensive insulin group (1.18+/-0.43 vs. 0.24+/-0.11, P<0.01). Light microscopic and electron microscopic examinations showed that intensive insulin therapy could alleviate the injury to myocardial cells and structural changes. CONCLUSION: Intensive insulin treatment possesses protective effect on cardiomyocytes after a severe burn, and it is related to its up-regulation of phosphorylation level of Akt in cardiomyocyte, thus inhibiting the damage to myocytes.

[Application with a series of orthotic splints for recovery of hand function after burn].

OBJECTIVE: To observe the effect of static and dynamic splints on recovery of hand functions in burn patients. METHODS: Thirty-two burn patients with 52 injured hands were treated with orthotic splints (single or combined application) during different therapeutic stages. Carroll's upper limb functional test was used to evaluate the function of upper limbs and hands from rough to fine movements, including grasp, pinch, nip, forearm pronation and supination, fetching, etc. The hand functions were compared before and after treatment. RESULTS: There were 7 hands with grade IV function, 15 hands with grade III, 23 hands with grade II, and 7 hands with grade I before treatment, while 9 hands achieved grade IV function, 28 hands grade V, 9 hands grade VI, and 6 hands grade III after treatment for three months. Twenty-eight patients with 46 hands recovered well enough to handle daily chores, including digital opposition, palmar opposition, grasp, pinch, etc. CONCLUSION: The manual splints offer good effects on preventing and treatment scar contracture of hand after burn, and they can promote the recovery of hand functions.