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So far, studies on the mechanism of scar formation have mainly focused on cells, cytokines and extracellular matrix. Some studies have shown that fibroblast is one of the most important element in the process of scar formation, while epidermal and endothelial cells exert synergistic effects as well. Genetic factor can not be ignored in scar formation, either. Recently, studies have shown decisively the loss or damage of the three-dimensional structure of dermal tissue is the initiator of scar formation. Thus, the defect of epidermis template is proposed as a theory in order to explain the mechanism of scar formation. There are various techniques for scar treatment. The commonly accepted methods are physical therapy, pressure therapy, pharmaceutical therapy, radiotherapy, etc.

It is important to establish some comprehensive wound healing centers in order to treat those complicated chronic skin wounds. In this paper, I would like to summarize our practices in some hospitals dealing with the construction of wound healing centers and give my suggestions for their future development.

Objective: To form a wound information management scheme with objectivity, standardization, and convenience by means of wound information management system., Methods: A wound information management system was set up with the acquisition terminal, the defined wound description, the data bank, and related softwares. The efficacy of this system was evaluated in clinical practice., Results: The acquisition terminal was composed of the third generation mobile phone and the software. It was feasible to get access to the wound information, including description, image, and therapeutic plan from the data bank by mobile phone. During 4 months, a collection of a total of 232 wound treatment information was entered, and accordingly standardized data of 38 patients were formed automatically., Conclusions: This system can provide standardized wound information management by standardized techniques of acquisition, transmission, and storage of wound information. It can be used widely in hospitals, especially primary medical institutions. Data resource of the system makes it possible for epidemiological study with large sample size in future.

Objective: To compare the morphological difference between dermal tissue of normal skin and that of scar in rat, and to explore its structural pattern., Methods: The full-thickness skin and the scar tissue formed 3 weeks after wound healing from SD rats were harvested as samples, which were prepared appropriately afterwards. Samples were scanned and imaged with synchrotron radiation technology, micro-CT, and phase-contrast imaging technology. The images were rebuilt with three-dimensional software., Results: The micro-CT was materialized by using X-ray generated by synchrotron radiation light source. The structure of dermal tissues was clearly shown with the assistance of phase-contrast imaging technology in the process. It was demonstrated that the dermal tissues of normal skin of rat were mainly composed of collagenous fibers, which twined together to form an olive-like structure. These olive-like structures as basic units were arranged randomly in a certain way. The collagenous fibers in dermal tissue of the scar were arranged in a parallel manner, while some fibers were crooked and arranged in a disorderly manner., Conclusions: Dermal tissue of normal skin in rat has stable three-dimensional structure, and its basic structure and manner of composition are obviously different from those of scar dermal tissue.

Following the development of social economy, the acceleration of aging problem, and the changes in disease spectrum, the incidence of various chronic wound diseases increased significantly, and it has become one of the most frequently encountered diseases that affect the people's health. The contradiction between the increase of medical need of wound diseases and the insufficiency of the medical service in our country is becoming increasingly conspicuous. Wound healing department, as a new cross subject that has emerged as the times require, needs to be perfected in its diagnostic and treatment strategies and methods. At present time, how to explore the new theory and pathologic mechanism of various chronic wounds, in order to establish the clinical guidelines in diagnosis and treatment that conform to national conditions of our country, and to establish efficient clinical pathway and medical-seeking model have become serious challenges to the establishment of wound healing department in our country. Thus, it is imperative for us to enhance the connotation of establishment of wound healing department. For this purpose, this article mainly elaborates on three aspects, including "enriching traditional diagnostic system with new theory and new technology", "improving treatment effect by ameliorating traditional methods and absorbing new technology from relating subspecialty", "establishing a new medical-seeking model by applying digital technology and vertically integrating medical resources".

Objective: To investigate the accumulation of advanced glycation end products (AGE) and the inflammatory response of skin and wound in diabetic patients, and to analyze their relationship in vitro., Methods: Histological staining and immunohistochemical staining was respectively performed on skin and wound tissue specimens collected from 10 patients with Type II diabetes mellitus (diabetes group) and 12 non-diabetic patients with skin injury (control group) to observe the arrangement of collagen and the distribution of inflammatory cells, and to determine the expression levels of AGE and its receptor (RAGE). Malondialdehyde (MDA) levels in skin and wound tissue homogenates were assayed by enzyme-linked immunosorbent assay. In vitro, human neutrophils were isolated and treated with RPMI-1640 culture medium or that containing AGE-human serum albumin in the concentration of 0.315, 0.625, 1.250 mg/mL, and they were identified as normal control (NC) group, low concentration (L) group, moderate concentration (M) group, and high concentration (H) group. Cell viability in each group was determined by MTT colorimetric assay, and the reactive oxygen species (ROS) in cell was measured with 2', 7'-dichlorofluorescein-diacetate. Data were processed with t test., Results: Compared with those of skin in control group, collagens of skin tissues in diabetes group atrophied and disorderly arranged. Inflammatory cells in wounds in diabetes group were dispersed, in which collagens arranged loosely and irregularly, as compared with those of wounds in control group. Expression levels of AGE and RAGE of skin in diabetes group were higher than those in control group. In diabetes and control groups, especially in diabetes group, the numbers of RAGE-positive cells in wound tissue were more than those in skin tissue. Large amount of inflammatory cells with positive expression of RAGE were observed in diabetes group. MDA level of skin and wound tissue in diabetes group was respectively (6.3 ± 1.0), (7.1 ± 2.4) nmol per milligram protein, which were obviously higher than those in control group [(2.9 ± 1.0), (3.6 ± 1.4) nmol per milligram protein, with t value respectively 8.017, 4.349, P < 0.05 or P < 0.01]. Cell viability and ROS levels in neutrophils were increased in L, M, and H groups [(59 ± 8)%, (77 ± 5)%, (67 ± 6)% and 1.67 ± 0.14, 2.13 ± 0.17, 3.48 ± 0.48] as compared with those in NC group [(34 ± 5)% and 0.58 ± 0.06, with t value respectively 7.195, 14.890, 11.130 and 20.195, 24.905, 16.864, P < 0.05 or P < 0.01]., Conclusions: Abnormal oxidative stress in diabetic skin leads to an atypical origin of wound repair. AGE-RAGE effect is a critical mediator for oxidative stress in diabetic wound tissue during wound healing.

Objective: To analyze the relationship between cutaneous glycometabolic disorders and cutaneous neuropathy in diabetic rats, and to look for the mechanism of neuropathy and impaired wound healing., Methods: Eighty male SD rats were randomly divided into the normal control group (NC, n = 20), diabetic group (D, n = 20), aminoguanidine-interfered group (AI, n = 20), and insulin-interfered group (II, n = 20) by drawing lots. Diabetes was reproduced in rats of D, AI, and II groups with intraperitoneal injection of streptozotocin (STZ). Then, rats in AI group were fed with 100 mg×kg(-1)×d(-1) aminoguanidine, while rats in II group were subcutaneously injected with insulin for satisfactory control of blood glucose. Changes in mechanical and heat pain thresholds of pad of hind limb were measured at post injection week (PIW) 2, 4, 8. Skin specimens were collected during PIW 2-8 from pads for determination of contents of glucose, advanced glycation end product (AGE), substance P (SP), calcitonin gene-related peptide (CGRP), and observation of distribution and ultrastructure of skin nerve fibers. Data were processed with t test., Results: The mechanical and heat pain thresholds in D group at PIW 2 [(6.3 ± 1.5) g, (6.0 ± 0.9) s, respectively ] were obviously lower than those in NC group [(13.0 ± 3.2) g, (10.3 ± 1.2) s, with t value respectively 2.71, 3.42, P values all below 0.05]. Contents of glucose and AGE in skin tissue in D group were significantly increased when compared with those in NC group, especially at PIW 8 [(2.85 ± 0.33) mg/g, (31.7 ± 3.2) U/mg of hydroxyproline vs. (0.82 ± 0.22) mg/g, (22.2 ± 1.9) U/mg of hydroxyproline, with t value respectively 1.65, 6.47, P values all below 0.01]. The myelinated nerve fibers were edematous and degenerated, with axons compressed, while the unmyelinated nerve fibers were vacuolated, with microfilament and microtubule disorderly arranged. Content of SP in skin tissue in D group was lower as compared with that in NC group, especially at PIW 2 [(16.8 ± 3.4) pg/g vs. (28.5 ± 5.0) pg/g, t = 2.42, P < 0.01]. There was no obvious difference in content of CGRP between NC and D groups, and also in content of glucose in skin between D and AI groups. Compared with those in D group, content of AGE in AI group at PIW 8 was decreased markedly [(27.2 ± 1.4) U/mg of hydroxyproline, t = 3.38, P < 0.05]; contents of glucose and AGE in II group at PIW 8 were significantly decreased [(1.42 ± 0.38) mg/g, (23.6 ± 1.3) U/mg of hydroxyproline, with t value respectively 1.74, 8.17, P < 0.05 or P < 0.01]. Compared with that in D group, contents of SP in AI and II groups were increased, with a delay in time of trough value. Content of CGRP showed no obvious difference among D, AI, and II groups., Conclusions: High glucose and accumulation of AGE are key mediators of cutaneous neuropathy and impaired wound healing in diabetes mellitus, which confirms that diabetic wound takes an atypical footing during wound repairing. Aminoguanidine and insulin can reduce contents of glucose and AGE in diabetic skin tissue, and ameliorate diabetic cutaneous neuropathy.

Objective: To investigate the effects of aminoguanidine cream on the proliferation of keratinocytes (KC), content of advanced glycosylation end products (AGE) and oxidative stress in skin tissue of rats with diabetes., Methods: Stearic acid, liquid paraffin, vaseline, lanolin, isopropyl myristate fat, glycerol, 50 g/L alcohol paraben, aminoguanidine hydrochloride etc. were mixed in certain proportion to make aminoguanidine cream, and cream without aminoguanidine was used as matrix. The dorsal skin of normal rats were harvested and treated by aminoguanidine cream with dose of 5, 10 g/L, or 5 g/L together with 10 g/L azone. The transdermal effect was respectively measured at post treatment hour 2, 4, 7, 10, 12, 24. Thirty SD rats were divided into normal control (NC, n = 6), diabetes (D, n = 8), aminoguanidine cream-interfered (AI, n = 8), matrix cream-interfered groups (MI, n = 8) according to the random number table. Diabetes was reproduced by intraperitoneal injection of STZ (65 mg/kg) in rats of D, AI, and MI groups, and rats in NC group were injected with 0.05 mmol/L citrate buffer as control. One week later, dorsal skin of rats in AI and MI groups were respectively treated with 10 g/L aminoguanidine cream and matrix cream by external use for 4 weeks. AGE content was determined with fluorescence detection from skin collagen extract. KC cell cycle was detected by flow cytometry. Skin tissue specimens were obtained for determination of levels of superoxide dismutase (SOD), malondialdehyde (MDA), myeloperoxidase (MPO), and total antioxidant capacity. Data were processed with t test., Results: Transdermal effect of aminoguanidine cream with dose of 10 g/L was better than that with 5 g/L or 5 g/L + 10 g/L azone cream. One rat was not induced successfully in MI group. Four weeks after model reproduction, 4 rats died in D group and 1 rat died in AI group. The AGE content in D group was obviously higher than that in NC group [(36.8 +/- 2.6), (24.6 +/- 2.7) U per milligram hydroxyproline, respectively, t = 7.2, P < 0.01], and that in AI group [(28.6 +/- 3.7) U per milligram hydroxyproline] was also lower as compared with that in D group (t = -3.9, P < 0.05). There was no significant difference in AGE content between MI [(32.2 +/- 5.2) U per milligram hydroxyproline] and D groups (t = 1.6, P > 0.05). The percentage of KC in S phase was obviously lower in D group than in NC group [(5.3 +/- 0.6)%, (7.6 +/- 0.9)%, respectively, t = 4.50, P < 0.01], while that in MI group [(9.2 +/- 1.5)%] was higher as compared with that in D group ( t = 4.90, P < 0.01). It was more higher in AI group than in D group on KC percentage in S and G2/M phase (with t value respectively 6.80, 3.17, P values all below 0.01). The oxidative stress indexes of skin tissue in D group were all higher than those in NC group, in which levels of MPO and SOD showed statistical difference (with t value respectively 4.4, 3.7, P values all below 0.05). The oxidative stress indexes were all lower in AI group than in D group, especially in SOD level (t = -1.4, P < 0.05). Levels of MAD, MPO in MI group were significantly lower than those in D group (with t value respectively 2.6, 2.9, P values all below 0.05)., Conclusions: Aminoguanidine cream can promote KC proliferation and appropriately reduce oxidative stress through inhibiting AGE formation to a certain extent in skin tissue of rats with diabetes. Signal use of matrix cream can also reduce oxidative stress in skin tissue of rats with diabetes.

Discipline of wound healing, has been emerged with the demand of patients suffering from various wounds. A unique way different from traditional medical system, in accordance with the incidence of wound diseases, medical demand, and current medical system of China, should be operated for the specialty, so as to benefit medical service for patients, rational allocation of medical resources. An overall layout with characteristic of "small ward, big clinic" is likely to meet the discipline demand associated with wound diseases, which present the linkage mechanism between wound healing department and community health system. By means of jointing wound healing clinic in community, two-way referral pathway for patients, training for general practitioner in community, guarantee and incentive system, an new operation pattern of wound healing discipline would be formed, described as linkage mechanism of wound healing department and community health system.

Objective: To determine the anti-inflammatory functions of different cysteine mutants of apolipoprotein A-I recombinant HDLs., Methods: The recombinant HDLs (named rHDL52, rHDL107, rHDL173, rHDLwt) were reconstituted by mixing wild types or their mutants with dipalmitoyl phosphatidylcholine. And the in vivo effects on lipopolysaccharide (LPS)-induced endotoxemia were examined in mice. The plasma levels of plasma tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6 in by ELISA were tested. And we also set up two control groups: LPS and saline., Results: The rHDL52 mice had a significant decrease of plasma TNF-alpha and IL-1beta and the protection of lung against acute injury. 24 h post-injection as compared with rHDLwt group [TNF-alpha: (135.28 +/- 12.84) pg/ml, IL-1beta: (82.00 +/- 8.19) pg/ml], the rHDL52 mice exhibited a higher capability of lowering the plasma levels of TNF-alpha and IL-1beta [(39.66 +/- 2.44) pg/ml, (66.83 +/- 6.24) pg/ml, both P < 0.05]. And, as indicated by histological sections of lung tissue, the rHDL52 mice could also lower the infiltration of inflammatory cells in lung., Conclusion: rHDL52 has a higher anti-inflammation capability than wild type rHDLwt.

Objective: To determine the anti-inflammatory functions of different cysteine mutants of apolipoprotein A-I recombinant HDLs., Methods: The authors reconstituted recombinant HDLs (namely rHDL74, rHDL129, rHDL195 and rHDL228) by mixing wild type or those mutants with dipalmitoyl phosphatidylcholine and examined their in vivo effects upon LPS-induced endotoxemia in mice., Results: At 24 h post-injection, mice receiving rHDL74 [TNF-alpha: (24 +/- 3) pg/ml; IL-1beta: (45 +/- 5) pg/ml] had a significant decrease of plasma tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta) as compared with control mice receiving either saline or rHDLwt [TNF-alpha: (135 +/- 12) pg/ml; IL-1beta: (82 +/- 8) pg/ml, P < 0.05]. Administration of rHDL74 to mice injected with LPS also led to a protection of lung against acute injury and attenuation of endotoxin-induced clinical symptoms in mice as compared with controls injected with LPS only., Conclusion: Compared with rHDLwt, rHDL74 exhibits higher anti-inflammation capabilities. And it may be a potential clinical candidate for therapy for endotoxin-induced septic shock.

Objective: To understand the influence of accumulation of advanced glycosylation end products (AGE) on wound healing of burn rats complicated with diabetes., Methods: Seventy-five SD rats were divided into control, diabetes, and aminoguanidine-interfered groups in completely randomized method, with 25 rats in each group. All rats were subjected to deep partial-thickness scald. Diabetes was reproduced in rats of diabetes and aminoguanidine-interfered groups. Rats in aminoguanidine-interfered group were fed with 100 mg x kg(-1) xd (-1) aminoguanidine. Rats were sacrificed on post-scald day (PSD) 0, 3, 7, 14, and 21, and portrait of the wounds were taken. Full-thickness skin tissue specimens were obtained for determination. Specimens of epidermis from back of SD rats were obtained for KC cultivation and verification. Wound healing rate, glucose content in skin tissue, morphologic change in wound tissue, AGE distribution in skin tissue, influence of AGE on proliferation and apoptosis of KC were observed., Results: Wound healing rate of rats was respectively lower in diabetes group than that in control group on PSD 7, 14, and 21 (P < 0.01), but it was obviously higher in aminoguanidine-interfered group than that in the former 2 groups (P < 0.01). Glucose content of rat skin in diabetes group was (2.62 +/- 0.19) mmol/g, and it was (2.58 +/- 0.07) mmol/g in aminoguanidine-interfered group, both higher than that in control group [(1.04 +/- 0.09) mmol/g, P < 0.01]. In control group, limited intensive infiltration of inflammatory cells was found in the wound with necrotic tissue formation which fell off in time, and with no obvious delay of wound healing. In diabetes group, infiltration of inflammatory cells in wounds of rats appeared slowly, but diffusely and persistently; necrotic tissue formed and fell off late in time, with obvious delay of wound healing. In aminoguanidine-interfered group, intensive infiltration of inflammatory cells was observed in time, and the time of necrotic tissue formation and sloughing, and wound healing were respectively earlier than that in diabetes group. Sporadic disposition of small amount of AGE was found in rats in control group. AGE accumulation increased significantly in rats in diabetes group. AGE content decreased significantly in rats in aminoguanidine-interfered group after administration of aminoguanidine. KC proliferation decreased significantly in concentration dependent manner 48 hours after AGE stimulation. Absorbance value of AGE decreased in each AGE-interfered group (P < 0.01). Early Annexin-V positive apoptotic KC rate was obviously higher in 100 ug/mL AGE-interfered group (15.1 +/- 2.3)% than that in control group [(11.2 +/- 1.2)%, P < 0.05]. There was no statistical significance between 100 ug/mL AGE-interfered group (14.3 +/- 3.5)% and control group (15.2 +/- 2.4)% in respect of the rate of double-positive cells apoptosis at final stage (P > 0.05)., Conclusions: Hyperglycemia may inhibit proliferation of repairing cells such as KC through AGE accumulation, thus impedes wound healing. Reduction of AGE accumulation could ameliorate wound healing delay due to diabetes.

Objective: To explore the effect of three-dimensional structure of dermal matrix on biological behavior of fibroblasts (Fb) in the microcosmic perspective., Methods: The three-dimensional structure of dermal tissue was analyzed by plane geometric and trigonometric function. Microdots structure array with cell adhesion effect was designed by computer-assisted design software according to the adhesive and non-adhesive components of dermal tissue. Four sizes (8 microm x 3 microm, space 6 microm; 16 microm x 3 microm, space 6 microm; 16 microm x 5 microm, space 8 microm; 20 microm x 3 microm, space 2 microm) of micropier grid used for cell culture (MPGCC) with cell-adhesive microdots, built up with micro-pattern printing and molecule self-assembly method were used to culture dermal Fb. Fb cultured with cell culture matrix without micropier grid was set up as control. The expression of skeleton protein (alpha-SMA) of Fb, cell viability and cell secretion were detected with immunohistochemistry, fluorescent immunohistochemistry, MTT test and the hydroxyproline content assay., Results: The three-dimensional structure of dermal tissue could be simulated by MPGCC as shown in arithmetic analysis. Compared with those of control group [(12 +/- 3)% and (0.53 +/- 0.03) microg/mg, (0.35 +/- 0.04)], the expression of alpha-SMA [(49 +/- 3)%, (61 +/- 3)%, (47 +/- 4)%, (51 +/- 3)%] and the content of hydroxyproline [(0.95 +/- 0.04), (0.87 +/- 0.03), (0.81 +/- 0.03), (0.77 +/- 0.03) microg/mg] were increased significantly (P < 0.05), the cell viability of Fb (0.12 +/- 0.03, 0.13 +/- 0.04, 0.14 +/- 0.03, 0.19 +/- 0.03) cultured in MPGCC was decreased significantly (P < 0.05). When the parameters of micropier grid were changed, the expression of alpha-SMA, the cell viability and the content of hydroxyproline of Fb cultured in four sizes of MPGCC were also significantly changed as compared with one another (P < 0.05)., Conclusions: MPGCC may be the basic functional unit of dermal template, or unit of dermal template to call. Different three-dimensional circumstances for dermal tissue can result in different template effect and wound healing condition.

Objective: To explore the impact of advanced glycosylation end products (AGE)-modified human serum albumin (AGE-HSA) on keratinocyte migration and the mechanism thereof., Methods: AGE-HSA was prepared in vitro. Epidermal keratinocytes from Sprague-Dawley rats' back were cultured and treated with AGE-HSA of the terminal concentrations of 0, 30, 60, 90, 120, and 150 microg/ml for 1, 3, 5, and 7 days respectively. MTT method was used to detect the keratinocyte adhesion rate, expressed by absorbance. Keratinocyte migration ability was assessed by scratch wound healing assay and Transwell assay. Expression of integrin alpha3 was determined by flow cytometry. Scanning electron and inverted microscopes were used to observe the pseudopodium and microfilament of the keratinocytes. Immunofluorescence staining was used to detect the form of F-actin in the cells., Results: The adhesion rates of the keratinocyte cultured with AGE-HSA for 12 and 24 hours were (0.112 +/- 0.022) and (0.173 +/- 0.012) respectively, both significantly lower than those of the control group [(0.122 +/- 0.004) and (0.267 +/- 0.024) respectively, both P < 0.05)]. Scratch wound healing assay showed that the amount of migrating cells in the AGE-HSA group was (7 +/- 4)/HP, significantly less than that of the control group [(61 +/- 11)/HP, P < 0.05)], and Transwell assay showed that the amount of migrating cells in the AGE-HSA group was (72 +/- 18)/HP, significantly less than that of the control group [(288 +/- 52)/HP, P < 0.05]. The expression rate of keratinocyte integrin alpha3 in the AGE-HSA group was (3.2 +/- 1.2)%, significantly lower than that in the control group [(36.6 +/- 11.2)%, P < 0.05]. The spreading of cell body, and the formation of pseudopodium and microfilament of the AGE-HSA group were all depressed in comparison with the control group., Conclusion: Keratinocyte migration is inhibited by AGE accumulation in high glucose condition. The mechanism may be the abnormality in the integrin inside-out signaling pathway and AGE-RAGE signaling pathway.

The basic and clinical research in wound healing have made great progress in China in the past 50 years. The method of "intermingle skin transplantation" which was first advocated by surgeons of Ruijin Hospital in 1966 greatly reduced the amount of autologous donor skin, thus making the coverage of an extensive burn wound possible. This method is also known as "Chinese therapy". In 1986, doctors of Jishuitan Hospital reported successful coverage of an extensive burn wound with microautografts and allogeneic skin. The basic research of wound healing has been carried out since 1992, a series of studies showed the characteristics of biological behaviours of cells in concern, extracellular matrix and growth factor, the mechanism underlying progressive injury in deep second burn wound, the effect of "skin island" and the local immune tolerance induced by it (which are the key factors of intermingle transplantation). The induction of local immune tolerance has now become the research hot subject of skin transplantation immunology. Stem cell research in the field of wound healing has been extensively carried out. The theory of "dermal template defection" has been proposed as one of the mechanisms of scar formation. On the other hand, great progress has been achieved in the treatment of burns on the basis of clinical researches. Doctors of PLA 304 hospital found that excision of eschar on patients with extensive deep burn injury at early shock stage greatly decreased the occurrence of complications and mortality. Doctors of Ruijin Hospital reported that healing of deep second burn wound could be improved by tangential excision of burn eschar within 24 hours after burn injury. Doctors of Xiangya Hospital reported patients suffering from deep burns of the hands got satisfied functional restoration when treated with tangential excision of eschar while degraded dermal tissue could be retained with transplantation of autoskin grafts.

Impaired wound healing in diabetes is a significant clinical problem which is thought to be associated with neuropathy and angiopathy previously . The present study indicates that accumulation of glucose and glycometabolic products in skin tissue, as the result of glycometabolic disorders, which contributes to cutaneous environmental alterations in diabetes mellitus, and subsequently induces the abnormal cell behaviors, cytokine alteration and matrix modification. Thus, diabetic neuropathy and angiopathy might be regarded as the pathological outcome of cutaneous environmental alterations. In conclusion, glycometabolism disorders could be described as one of the initial events for the alteration involving in the underlying cutaneous disorder which impair healing process. The related research focuses on the initial event of controlling disorders in wound healing and therefore contribute to providing the strategy of treatment as based on these approaches.

Objective: To investigate the effect of advanced glycosylation end products (AGE) on cell cycle of epidermal keratinocyte and its possible signal pathway., Methods: 150 mg/L AGE-human serum albumin (AGE-HSA) was prepared in vitro. Primary cultured keratinocytes in logarithmic growth phase were harvested and divided randomly into: A group [with treatment of defined keratinocyte-SFM (DK-SFM) serum-free medium], B group (with treatment of DK-SFM medium including 150 mg/L AGE-HSA), C group (with DK-SFM medium after treatment of U0126) and group D (with D K-SFM medium including 150 mg/L AGE-HSA after treatment of U0126). Cell cycle distributions were analyzed by flow cytometer. The protein levels of cyclin D1, cyclin B1, CDK4 and p44/42 MAPK were measured by Western blot., Results: Compared with those of A group, the percentage of S-phase and G2/M-phase keratinocytes were decreased obviously in B group, the percentages of G2/M -phase keratinocytes showed the same tendency in C and D groups [(9.7 +/- 1.1)% , (9.8 +/- 0.7)%, respectively, P <0.05]. Compared with that of A group, the expression of cyclin D1 were decreased significantly in other groups, among which a weak expression was showed in D group. There was no obvious difference between A and B groups in CDK4, or cyclin B1 and p44/42 MAPK protein levels ,which were significantly higher than those in C and D groups., Conclusion: AGEs inhibit the progress of cell cycle of keratinocytes by downregulation of cyclin D1 expression.

Objective: To study the relationship between the degree of neovascularization and non-healing wounds in scalded rats with diabetic mellitus., Methods: Sixty Sprague-Dawley rats were randomly divided into control group (C, n = 30, with treatment of isotonic saline) and streptozocin (STZ)-induced diabetic group (D, n = 30, with treatment of STZ), and then they were inflicted with 20% TBSA deep partial thickness scald. Wound specimens were harvested immediately after scald and on 1, 3, 7, 10, 14, 21 post scald days (PSD) to observe histological changes, and wound healing rates were calculated. Degree of neovascularization in wound (labeled with blue microsphere) and the quantity of vascular endothelial cells (labeled with red CD31) were also measured by double-labeling immunofluorescence., Results: Compared with those in C group, Wound healing rate and histological value scores were lowered, and the degree of neovascularization was abated markedly at each time point. The degree of neovascularization in D group (12.00 +/- 1.40) was obviously lower than that in C group on 7 PSD (60.00 +/- 3.00, P <0.01). There was no obvious difference in the number of vascular endothelial cells in both groups, however, the majority of endothelial cells had not formed functional capillaries in D group., Conclusion: Vascular endothelial cell can proliferate actively with poor blood supply in diabetic nonhealing with deep partial-thickness scald wounds, but it is still poor in blood supply due to lack of functional capillaries.

Objective: To investigate the effects of advanced glycation end products (AGE) on the biological behavior of neutrophils in vitro, to look for the relationship between accumulation of AGE and abnormal inflammation in wound healing in diabetic mellitus patients., Methods: Neutrophils were isolated from SD rats and incubated in vitro. The cells were divided into four groups according to different concentrations of AGE in cell suspension: control group (C, with treatment of RPMI - 1640), A group (with treatment of 0.315 mg/mL AGE + RPMI - 1640), B group (with treatment of 0.625 mg/mL AGE + RPMI - 1640), D group (with treatment of 1.250 mg/mL AGE + RPMI - 1640). Activity of neutrophils were determined by MTT colorimetric assay. Selectin-L mRNA expressions were analyzed by reversible transcription polymerase chain reaction (RT -PCR) technique. The levels of reactive oxygen species (ROS) in neutrophils were measured with DCFH-DA method. The protein concentration of neutrophil elastase (NE) was assayed by ELISA., Results: The activity of neutrophils were obviously increased in A, B, and D groups when compared with that in C group [(0.170 +/- 0.040) in C group, (0.320 +/- 0.030) in A group, (0.380 +/- 0.020) in B group, (0.290 +/- 0.010) in D group, P <0. 05]. The expression of Selectin-L mRNA in A, B, D groups were significantly higher than that in C group (0.95 +/- 0.08, 1.36 +/- 0.27, 0.50 +/- 0.26.vs.0.36 +/- 0.26, P < 0.05. respectively). The ROS levels in A, B, D groups was markedly higher than that in C group (1.64 +/- 0.20, 2.16 +/- 0.26, 3.26 +/- 0.75. vs. 0.72 +/- 0.15, P <0.05, respectively). The levels of NE in A, B, D groups were significantly increased when compared with that in C group(1.98 +/- 0.43, 2.50 +/- 0.43, 2.01 +/- 0.18 vs 0.91 +/- 0. 21, P <0.05, respectively)., Conclusion: AGE can enhance the activity of neutrophil, with change in cellular biological behaviors, which may be one of main reasons for abnormal inflammation in wounds of diabetes mellitus patients.

Objective: To compare the difference between the burn wound and diabetic ulcer wound, and to preliminarily analyze the nonhealing mechanism of diabetic unclear., Methods: The tissue of foot ulcer of diabete patients and skin wound tissues from burn patients were harvested. The levels of (FGF)2 and VEGF in the wound tissues were determined after tissue cultivation with enzyme-linked immunosorbent assay (ELISA). The changes in micro-vascular density (MVD) were examined by immunohistochemistry. Human umbilical vein endothelial cells were cultured in medium containing different components, and divided into following groups: A (with treatment of 5 mmol/L glucose for 7 days), B (with treatment of 30 mmol/L glucose for 7 days) and C (with treatment of 30 mmol/L Mannitol for 7 days) groups, then the level of VEGF protein was determined by ELISA., Results: The levels of FGF2 and VEGF protein in the burn wound were (59 +/- 3) ng/ml and (56 +/- 7) pg/ml, respectively, which were obviously lower than those in diabetic ulcer wound [(89 +/- 6) ng/ml, (108 +/- 5) pg/ml, P < 0.05]. There was also obvious difference in MVD between two kinds of wound (P < 0.05). The level of VEGF protein in both wounds were similar after the addition of FGF2 to the cell culture in vitro, while there were statistically significant difference 2 and 5 days after removal of FGF., Conclusion: The nonhealing mechanism of diabetic ulcer wound may be related to the inhibition of vacuolation and low expression of factors controlling vessel growth.

Objective: To explore the changes of the biological function of dermal fibroblasts (FBs) in the wounds of diabetic and non-diabetic burned rats and the pathogenesis of impaired wound healing in diabetes., Methods: 80 Sprague-Dawley (SD) rats weighing 220 g were randomly divided into control and STZ-induced diabetic groups, and then deep partial thickness scald involving 10% TBSA was reproduced in the two groups. The diabetic groups were randomized into pre-scalding, post-scalding day (PSD 3), PSD 7, PSD 14 and PSD 21 groups, with 6 rats in each group. Controls were also randomized into 5 groups. Skin specimens from the wound were harvested at each time point. Cell cycles of FBs were analyzed with flow cytometry. The amount of hydroxyproline in the skin tissue was assessed on 0, 3, 7, 14, and PSD 21. The type I and III collagens were determined by ELISA. The expression of alpha-SMA in the dermal fibroblasts of each group was assessed by immunohistochemistry method. Transmission electron microscopy was used to observe the ultrastructure changes of FBs., Results: Compared with that in the normal rats, the percentage of the cells in G(0)/G(1) phase in the DM group was evidently lower on PSD 0 (65.79 +/- 5.24 vs 82.43 +/- 9.68, P < 0.01). After the scalding, the percentage of the cells in G(0)/G(1) phase in DM group was significantly higher (70.00 +/- 4.27 vs 42.04 +/- 12.96, on PSD 3, P < 0.01), meanwhile the percentage of S phase was remarkably lower than those in C group on 3, 7, 14, 21PSD (P < 0.05, P < 0.01). The amount of hydroxyproline in the diabetic skin tissue was obviously lower than those of the responding control groups before (0.72 +/- 0.06 vs 1.42 +/- 0.28, P < 0.01) and after burn injury (P < 0.01). Furthermore, the rate of I/III collagen on 7, 14 and PSD 21 was much higher in DM group than that in C group (P < 0.01). The expression of alpha-SMA in DM groups on PSDS 3, 7, 14 and PSD 21 was evidently lower than those of the controls (levels 10.28 +/- 3.99, C group 28.42 +/- 2.73, on PSD 14, P < 0.01), although that inclined to be heightened after burn injury. Ultrastructure changes of FBs in the wounds of diabetic rats could be observed, such as the outstretched endoplasmic reticulum, un development of Golgi's body, lackness of microtubule and microfilament, a sharp increase of cytolysosomes, and so on., Conclusion: The FB proliferation in the diabetic skin is abnormal, the synthetical ability of collagen is weakened, the expression of alpha-SMA is insufficient, the microtubule and microfilament is lack, and the number of cytolysosomes increases. The pathogenesis of impaired-wound healing in diabetics might be related with the above mentioned factors.

Objective: To explore the biological function of vascular endothelial cells from hypertrophic scar, and to analyze the relationship between them., Methods: The samples from human hypertrophic scar and normal skin tissue were harvested for histological examination. Then vascular endothelial cells were purified and isolated from the samples, and the level of transforming growth factor (TGF) beta1, platelet derived growth factor (PDGF), endothelin1 (ET)-1, fibroblast growth factor (FGF)2 and vascular endothelial growth factor (VEGF) were determined in a single cell with ELISA., Results: Few capillary vessels were observed in normal skin under microscope, while an increased number of them were present in hypertrophic scar, with slender, tortuous in morphology and even occluded. The diameter of blood capillary in hypertrophic scar was tiny under electron microscope, and the exfoliation of endothelial cells was observed. The levels of TGF-beta1, PDGF, ET-1, bFGF and VEGF from vascular endothelial cells from hypertrophic scar were 60 +/- 8, 30 +/- 4, 0.12 +/- 0.03, 52 +/- 5, 18.1 +/- 1.2 microg/cell, respectively, which were obviously lower than those in normal skin (P < 0.05)., Conclusion: The biological function of vascular endothelial cells was attenuated in the hypertrophic scar, which mightbe the result of the production of large amounts of collagen in the scar tissue, as well as hypoxia.

Objective: To study hypertension control, follow up and the factors associated with the rate of hypertension control., Methods: Through a community-based study, the routine data were collected through a community hypertension managing software for one year., Results: There were 3375 hypertension patients above 60 years old recruited in the information system. In the baseline, the rate of blood pressure control was 63.5%, and arranging intervals up to 6 months was 66.9%. Hypertension control rate for the baseline, the third month and the sixth month was 61.8%, 62.4% and 61.6%, respectively (chi2 = 0.16, P = 0.69). Among hypertensives whose blood pressure was stabilized in baseline, hypertension control rates for the third month and the sixth month was 72.9.8% and 72.1%, respectively (chi2 = 0.26, P = 0.61). Blood pressure stabilized over 6 months in comparing with others, and the proportion for regular taking medication was 96.2% and 97.7% (chi2 = 3.58, P = 0.06). The proportion for physical activity, less salt intake, weight control was significantly higher in the patients whose blood pressure control well over 6 month., Conclusion: Rate of blood pressure control among elderly patient with hypertension who frequently consults the doctor in the community is high. Ineffectiveness in systolic and diabetes control is the important factor, which decreases the rate of blood pressure. Physical activity, less salt intake, and weight control are of help to hypertension control. For those, the blood pressure are stabilized, a follow up with 3 to 6 months interval is appropriate.

Dermal defection and the degree of its loss determine the natural process of wound healing, which is the key reason leading to excess scar hyperplasia. The function of tri-dimensional structure in dermis acts as a template to regulate the properties of reparative cells. The template structure induces the reparative cells to grow into the structure which changes the skin mechanic status on wound area. Also, the component of extracellular matrix can affect behaviours of fibroblasts negatively or positively, for the reason that the structure of dermal tissue has a permissive effect on the dermal components in regulating behaviours of reparative cells. Therefore, the behaviors of cells depend on the structure of the template. The suitable tri-dimensional structure of dermis facilitates normal cell cycling. The more the structure of dermis closed to its physiological status, the better the biological behaviors of cells act. Moreover, the integrity as well as the continuity of dermal tissue is the prerequisite for serving as a template. The damage to the integrity and the continuity of dermal tissue may be one of the key reasons to lead abnormal tissue repair and scar formation. Thus, we hypothesize that the loss of dermal template may be one of the mechanism of abnormal scar formation and propose the theory of extracellular matrix framework deficiency or destruction.

Objective: To investigate the biological characteristics of dermal fibroblasts of the diabetic rats with deep partial thickness scald, and to explore its relationship with delayed wound healing due to diabetes., Methods: Sprague-Dawley rats weighing 250 g were randomly divided into control (NM, n=40) and STZ-induced diabetic (DM, n=50) groups, and then deep partial thickness scald involving 10% TBSA were reproduced in the two groups. Skin samples were harvested from the wounds on 0, 3, 7, 14 and 21 post scald day (PSD) for the determination of certain histological characteristics., Results: The thickness of dermis layer in DM group before injury was obviously thinner than that in NM group (P < 0.01). There was an infiltration of a large amount of chronic inflammatory cells and increased content of cutaneous glucose in the dermal tissue in DM group (2.77 mg/g) compared with 0.85 mg/g in NM group, (P < 0.01). An accumulation of advanced glycation end products (AGEs) was found in the dermal tissue in DM group. After the scalding, the percentage of fibroblasts in S phase and hydroxyproline synthesis in DM group was evidently lower than those in NM group. But the apoptosis rate of fibroblasts was much higher in DM group than that in NM group (P < 0.05 or 0.01)., Conclusion: It is found that the high contents of glucose and AGEs in diabetic skin exert untoward effects on biological characteristics of dermal fibroblast, probably constituting one of the underlying mechanisms of delay wound healing of scald in diabetic rats.

Objective: To explore the latent skin lesions in streptozotocin-induced diabetic rats and the mechanism of insulin prevention., Methods: 81 male Sprague-Dawley (SD) rats were randomized into control (C, n = 27) and STZ-induced diabetic groups (n = 54), and then the diabetic rats were randomized into 2 groups: Group A group (n = 27) that was treated with insulin enough to control the high concentration of blood glucose strictly, and Group B group (n = 27) in which insulin was given too nut not sufficient to control the high blood glucose. Twenty-seven normal rats were used as controls. Four, eight, and twelve weeks after STZ-induction, skin specimens from the back were collected to undergo hematoxylin-eosin staining and histological examination. The skin glucose content was measured by Beckman's autoanalyzer. The skin advanced glycation end products (AGEs) concentration was assessed by fluorescence spectrophotometry and immunohistochemistry. The ultrastructure changes of skin microvessel were observed by electron microscopy., Results: Twelve weeks after the establishment of the DM model the skin thickness of Group B was decreased, the features of multilayer epithelium structure disappeared in epidermis, and part of the collagen fibers in dermis became atrophic, swollen and degenerated, infiltration of inflammatory cells to different degrees was found, and subcutaneous fat showed progressive atrophy or disappeared. However, such changes were not detected in Group A. The skin glucose contents of Group B at different time points were all higher than those of Group A and Group (all P < 0.01) without a significant difference between Groups A and C. The fluorescence values of skin collagen extracts of Groups A and B were significantly higher than that of normal rats. The 8-week fluorescence value of skin collagen extracts of Groups B was 34 U/mg +/- 4 U/mg, significantly higher than that of Group A (29 U/mg +/- 3 U/mg, P < 0.05). The 12-week fluorescence value of skin collagen extracts of Groups B was 41 U/mg +/- 4 U/mg, significantly higher than that of Group A (32 U/mg +/- 4 U/mg, P < 0.05). The 8-week AGEs positive expression rate of Group B was 32% +/- 4%, significantly higher than that of Group A (25% +/- 5%, P < 0.05), and the 12-week AGEs positive expression rate of Group B was 39% +/- 5%, significantly higher than that of Group A (27% +/- 4%, P < 0.05). Degeneration of endothelial cells and thickening of basement membrane were more markedly in Group B than in Group A., Conclusion: Accumulation of AGEs in skin and high concentration of glucose are important causes of diabetic skin complications. Insulin application at the early stage postpones the course of diabetic skin lesions with the possible mechanisms of lowering the high glucose, inhibiting AGEs synthesis, and blocking the action of AGEs.

Objective: To explore the influence of L-arginine supplementation on the plasma amino acid spectrum in burn patients., Methods: Ten burn patients were randomly divided into burn control (n = 5, with compound 14 amino acid injection accounting for 2% of the total caloric value), and experimental (n = 5, with intravenous injection of L-arginine which accounted for 2% of total caloric value) groups. The intake of other nutrients for these two groups of patients was the same. The nutrient regimen was begun on the 3 PBD, with one quarter of the daily supply. On 4 and 5 PBD, one half of the daily supply was given, and from 6 to 21 PBD full supplementation was given. Venous blood samples were collected on 3, 7, 14, 21 and 28 PBD for the determination of plasma levels of amino acids. Ten normal volunteers served as normal control., Results: The plasma level of citrulline in both groups was significantly lower than normal value (P < 0.05) on 3 PBD before L-arginine supplementation. There was no obvious difference in plasma levels of ornithine and arginine in the two groups on 3 PBD compared with normal value (P > 0.05). The plasma level of ornithine, citrulline and arginine in burn control group declined on 3 PBD. The plasma level of arginine in experimental group on 14, 21 and 28 PBD were 280 +/- 121 micromol/L, 223 +/- 106 micromol/L and 110 +/- 44 micromol/L, respectively, which were significantly higher than those in burn control group (124 +/- 21 micromol/L, 59 +/- 15 micromol/L, 50 +/- 26 micromol/L). The plasma level of ornithine (30 +/- 5 micromol/L) and citrulline (162 +/- 44 micromol/L) on 21 PBD in experimental group were markedly higher than those in burn control group (8 +/- 7 micromol/L, 66 +/- 4 micromol/L, P < 0.05 or 0.01). There was no difference in the plasma levels of other amino acids at all postburn time points between the two groups (P > 0.05)., Conclusion: The production process of L-arginine from citrulline was accelerated after burns. The plasma levels of L-arginine, ornithine and citrulline were increased markedly after L-arginine supplementation, while that of other amino acids was not influenced. The pharmacological effects of L-arginine may be related to the promotion of ornithine cycle.

Objective: To study the effect of the cutaneous and blood contents of glucose on wound healing in diabetic rats with superficial partial thickness scalding., Methods: 96 Sprague-Dawley rats were randomized into control group and STZ-induced diabetic group, inflicted with superficial partial thickness scalding of 10% TBSA on the back. The glucose content in the blood and wound tissue were evaluated before injury and at day 1, day 3, day 5, day 7, day 10 and day 14 after injury. Wound healing process in the rats was dynamically observed by naked eyes and histologically examined. The cell cycles of keratinocytes from wound site were determined before injury and at day 3, day 7 and day 10 after injury., Results: The concentrations of blood glucose in diabetic wound was significant increased than normal group (27.28 mmol/L +/- 0.80 mmol/L vs. 4.65 mmol/L +/- 0.14 mmol/L, P < 0.01). The content of local glucose in wound tissue were significantly correlated with that in the blood (r = 0.881, P < 0.05). When compared with the control group, wound healing of the diabetic rats were delayed with the characteristics of impaired epithelialization and decreased. percentages of S stage and G(2)/M stages of keratinocytes., Conclusion: Local glucose content in diabetic wound was varied with blood glucose concentration. The increased glucose concentration in diabetic wound was attributed to the impaired wound healing in diabetes. High glucose concentration could inhibit the epithelialization and decrease the keratinocyte proliferation.

Objective: To investigate the influence of dermal template on the biomechanical compliance of wound tissue during wound repair., Methods: One hundred and forty-four SD rats subjected to full-thickness skin loss on the dorsum were enrolled in the study, and they were randomly divided into A (n = 6, without grafting on wound), B (n = 6, with full thickness skin grafting on wound), C (n = 6, with razor thin skin grafting on wound) and D [n = 6, with acellular dermal matrix (ADM) and razor thin skin grafting on wound] groups. The tissue samples from the wounds were harvested 1, 2, 4, 6, 12 and 20 weeks after the operation. The biomechanical compliance of the wound was assessed by Instron biomechanics tensiometer. The expression of alpha-SMA in the dermal fibroblasts of each group was determined by immunohistochemistry (ABC) method., Results: The biomechanical compliance of the wound in D group was higher than that in A and C groups (P < 0.05), but lower than that in B group during 4 to 20 weeks after operation (P < 0.05). The expression of alpha-SMA in D group (7.53 +/- 0.98)% was lower than that in A (26.99 +/- 2.90)% and C (2.18 +/- 2.79)% groups (P < 0.01), but higher than that in B group at 4 weeks after operation (P < 0.05)., Conclusion: Dermal template might affect the scar formation during wound healing, in improving wound healing quality by enhancing the biomechanical compliance of wound tissue.

Objective: To explore the preventive and treatment effects of smectite powder on enteral bacterial translocation in scalded rats., Methods: Fifty-four Sprague-Dawley (SD) rats were randomly divided into three groups, i.e. normal control (A, n = 6), burn control (B, n = 24), and burn treatment (T, n = 24) groups. The rats in B and T groups were fed with tracing bacteria JM109, which was transfected with PUC19 plasmid in advance. The rats were subjected to 30% TBSA scald injury after the plasmid was shown to have colonized in the intestine. Smectite powder (0.6 g/day/kg) was fed to rats of T group immediately after the scalding, while those in B group received no smectite powder. Bacterial translocation in blood and mesenteric lymph nodes in all groups was observed and identified by enzyme digestion at 12 post scald hour (PSH) and on 1, 3 and 5 post-scald days (PSD). The contents of malondialdehyde (MDA) and superoxide dismutase (SOD) were determined in rat intestinal tissue. And the degree of injury to the entire small intestine was observed pathologically. The villus height of intestinal mucosa was measured, and the rate of epithelial nuclear splitting of mucosal crypts was calculated., Results: The number of rats with positive blood bacterial culture in B group was obviously higher than that in A and T groups (P < 0.05) on 1 and 5 PSD. The bacterial quantity in mesenteric lymph nodes (MLN) in T group on 1 PSD (38 +/- 16 CFU/g) and 5 PSD (68 +/- 20 CFU/g) were obviously lower than those in B group (228 +/- 67 vs 183 +/- 29 CFU/g, P < 0.05). There was significant difference in the intestinal contents of MDA and SOD between B and T groups at each time point (P < 0.05). The rat jejunum villus height and the epithelial nuclear splitting in the small intestine mucosa in T group were evidently higher than those in B group (P < 0.05 or 0.01)., Conclusion: Smectite powder is beneficial to the protection of the intestinal mucosa in scalded rats, and can effectively prevent postburn intestinal bacterial translocation in rats.

Objective: To investigate the rule and possible mechanism of epidermal proliferation in wound edge of deep partial thickness scald injury in rat., Methods: Twenty-four Sprague-Dawley rats inflicted with deep partial thickness scald were randomized into pre-scalding, 3 post-scalding day (PSD), 7PSD and 14PSD groups, with 6 rats in each group. Skin specimens from the wound edge were harvested for the observation of the histological characteristics of the epidermis. Cell cycles of epidermal cells were analyzed with flow cytometry. The expressions of cyclin D1, cyclin B1, cdk4 and the histone H1 kinase activity of MPF in epidermal cells were determined by Western blotting., Results: Augmentation of nuclei and nucleoli was found in the epidermal cells from the wound edge in 3PSD group, while increased number of epidermal cells with obviously augmented nuclei and nucleoli were found in 14PSD group. The percentage of the cells in S phase increased in 14 PSD group. The percentage of epidermal cells in G2/M phase began to increase in 3PSD group, and that in 7PSD (4.5 +/- 0.6) and 14PSD (5.4 +/- 1.0) groups were obviously higher than that in pre-scalding group (2.9 +/- 1.1, P < 0.05). The expression of cyclin D1 increased significantly in 3PSD group. The expression of cdk4 decreased in 3PSD group, but began to increase in 14PSD group. There was no difference in the expression of cyclin B1 among groups. The MPF activity was significantly increased in 14PSD group., Conclusion: There was enhanced DNA synthesis and mitosis in epidermal cells of rats with deep partial scald during early post-scald stage, and active proliferation of epidermal cells was observed on 14PSD. The expression of cyclinD1/cdk4 complex and the activity of MPF increased since 14PSD, indicating that there was a special regulative pattern during wound healing.

Objective: To investigate the influence of dermal template on the expressions of signal transduction protein Smad 3 and transforming growth factor beta1 and its receptor during wound healing process in patients with deep burns., Methods: Twenty burn patients with excision of full thickness burn in the extremities were enrolled in the study and divided into two groups, i.e. template interfering group (E, n = 20, grafting of dermal template [allogeneic acellular dermal matrix] with razor thin autoskin) and control group (C, n = 20, grafting of razor thin autoskin only). The contralateral side served as the self-control. Tissue samples from the burn wounds were harvested at 1, 2, 3 and 4 post-operative weeks (POW) for immunohistochemistry staining. The positive expression rates of TGF-beta1, TbetaRI, TbetaRII and Smad3 proteins were determined by image analysis system., Results: The positive expressions of TGFbeta1, TbetaRI, TbetaRII and signal transduction protein Smad 3 in the tissue samples in both groups could be identified during 1 approximately 4 POW, and they diminished thereafter with the process of wound healing. The expression rate of TGF-beta1 in E group was (13.08 +/- 4.65)% at 1 POW and (9.03 +/- 1.89)% at 4 POW. The positive expression rate of above indices in E group was obviously lower than that in C group in corresponding time points (P < 0.05)., Conclusion: The expression levels of TGFbeta1, TbetaRI, TbetaRII and Smad 3 protein in deep burn wounds could be lowered by mixed grafting of dermal template with razor thin autoskin, which might be beneficial in ameliorating of scar hyperplasia in the burn wound.

Objective: To investigate the influence of early tangential excision within 24 postburn hours on local wound inflammatory response and tissue injury in patients with deep partial thickness burn., Methods: Twelve patients with deep partial thickness burn were enrolled in the study. Tangential excision was performed within 24 postburn hours. The same wound of a patient was divided into three areas for harvesting tissue samples, i.e. pre-operation, post-operation and non-operation areas. For each patient, the biopsies from the pre-operation area were harvested before tangential excision, while those from post-operation and non-operation areas were harvested during 5 to 7 postburn days (PBDs). The contents of IL-8, MPO and MDA in wound tissue were determined by tissue culture and chemical colorimetry, respectively. HE and Mason's staining were employed to assess the degree of necrosis of the wound tissue., Results: The IL-8, MPO and MDA contents in the local wound tissue after tangential excision were 6.83 +/- 1.85 microg/L, 4.07 +/- 0.87 U/g, and 8.94 +/- 5.66 micromol/g, respectively, which were significantly lower than those from non-operation area (P < 0.01). The inflammatory response in the non-operative wound area was distinct with expansion of necrotic tissue area. In contrast, the local inflammatory response of the wound after tangential excision was ameliorated without the enlargement of necrotic tissue area., Conclusion: Tangential excision within 24 postburn hours could be beneficial in ameliorating local inflammatory response, and in preventing progressive deepening of the burn wounds, thus it could accelerate wound healing in patients with deep partial thickness burn.

Objective: To explore the influence of dermal defect and fat dome structure destruction in burn wounds on the formation of hyperplastic scar., Methods: Fifty two wounds in 24 burn patients with deep partial thickness burn indicating tangential excision in the extremities were enrolled in the study, and they were divided into three groups according to the extent of exposure of dermal fat granules, i.e. A (without fat exposure), B (with little fat exposure) and C (with much fat exposure) groups. These three groups were subdivided into A1 (without grafting), A2 (grafting with razor thin skin), B1 (without grafting), B2 (with razor thin skin grafting), C1 (without grafting) and C2 (with split-thickness skin grafting) groups, with 9 wounds in each group. The dermal depth and exposure rate of the fat granules in each group were measured and analyzed by KS400 photography analysis apparatus. The follow-up conditions of the scars 6 months after operation were evaluated with Vancouver remark system by Vancouver score assessment., Results: There was obvious difference in the dermal depth and exposure rate of the fat granules among all the groups (P < 0.05 or 0.01). The fat exposure rate was positively correlated with the extent of the dermal defect (gamma = 0.554, P < 0.05). The Vancouver score in group A was lower than that in B and C groups (P < 0.05), while that in B1 group (3.714 +/- 2.498) was evidently higher than that in other groups (P < 0.01). The scar score was lowered when the wounds were grafted with the dermis with its thickness similar to the depth of the defect, The scar score was increased along with the elevation of fat exposure rate (P < 0.05)., Conclusion: There was a positive correlation between the degree of dermal defect and that of hyperplastic scar after burns. The disruption of fat dome structure might also be an important factor in the scar development.

Objective: To explore the role of cytokines and keratinocytes in the survival mechanism of mixed auto and allogeneic skin grafting., Methods: Thirty-six SD rats were employed in the study. The rat model with mixed auto and allogeneic skin grafting and mixed human epithelial and lymphocytic culture (MELC) model were established. The change of IL-10 in the serum and the supernatant of the cultured tissue sample from the local wound was observed after the mixed skin grafting in scalded rats. And the role of epithelium in the induction of immunosuppression in vitro was monitored., Results: The serum IL-10 content in the rats with mixed skin grafting (25.89 +/- 2.82 ng/L) at 7 postoperative day (POD) was evidently higher than that in normal rats (14.20 +/- 2.43 ng/L) (P < 0.05). The IL-10 content in the culture supernatant of rat tissue samples exhibited evident different during 4-14 PODs (P < 0.05-0.01), while which was no difference to that in normal rat on 21st and 28th POD. The inhibiting effects of autologous epithelia and keratinocytes in MELC system were correlated with their dosage. After the adding of autologous keratinocytes to MELC system the cytokines secreted from Th1 could induce the secretion of cytokines from Th2 by IL-10 mediation. This effect could be corrected by the addition of monoclonal antibody of IL-10., Conclusion: The keratinocytes inlayed in the autoskin during mixed grafting could increase the local IL-10 level by activating Th2 cells, which might be one of the important reasons of the survival of mixed skin grafting.

Objective: To observe dynamically the influence of the application of dermal template on the p53 gene expression and apoptosis during wound repairing in burn patients., Methods: Twenty burn patients were enrolled in the study and were divided into experiment (E, n = 11) and control (C, n = 9) groups. The escharectomy wounds in patients with 3rd degree burn in E group were covered with dermal template overlain with thin split-thickness autograft, while those in C group were covered with thin split-thickness autograft only. Specimens were harvested from wounds of both groups at 1st, 2nd, 3rd, 4th and 5th post operative week (POW). The P53 expression and the apoptosis were assessed respectively by immunohistochemistry and by TUNEL kit. The change in cell number was observed after HE staining., Results: The P53 expression increased gradually along with the wound healing process from 1st to 4th POW, which was significantly higher than that in C group at 2nd, 3rd, and 4th POW (P < 0.05), and it reached the peak at 4th POW. Fibroblasts underwent apoptosis at 1st POW in E group, while apoptosis of the endothelial cells occurred mainly at 2nd and 3rd POW. There was obvious difference in the rate of apoptosis between the two groups in 3rd and 4th POW (P < 0.05). The numbers of fibroblasts and vascular endothelial cells in E group were smaller than those in C group., Conclusion: Application of dermal template overlain with thin split-thickness autograft to wounds could induce P53 expression and cell apoptosis, thereby reduce scar formation, resulting in improvement of the quality of wound healing.

Objective: To establish an animal model of hypertrophic scar on the rabbit ears and to observe the dynamic process of scar formation on the ventral side of the rabbit ears., Methods: Full skin defect (2 cm x 5 cm in diameter) was created on the ventral side of 60 ears in 32 New Zealand white rabbits. 1% silver sulfadiazine cream was applied to the wounds, and the dressing was changed once a week till wound healing. Four ears without operation were taken as control. Wound healing under natural condition was observed continuously for 12 months after the operation. The scar proliferation on the rabbit ears was observed by light microscope and transmission electron microscope, and the scar index was determined by computer image analyzing system., Results: The color, thickness and texture of the wounds on the rabbit ears after epithelization underwent a process of scar overgrowth, maturation and degeneration. The change in scar index was in accordance with the wax and wane of scar proliferation., Conclusion: The hypertrophic scar formed on the ventral side of rabbit ears after natural healing of full thickness skin wounds was similar to that in humans. The results indicated that this animal model was ideal for the study of the developmental mechanism of hypertrophic scars and for the evaluation of the efficacy of the prevention and treatment of hypertrophic scars.

Objective: To investigate the possible mechanism of L-arginine supplementation on the angiogenesis of burn wounds in diabetic rats., Methods: One hundred male Sprague-Dawley (SD) rats were used in the study and were randomly divided into A (scalding control, n = 25), B (scalding of the rats with diabetes, n = 25), C (L-glycine control, n = 25) and D (L-arginine supplementation, n = 25) groups. Diabetes was produced by intra-peritoneal injection of streptozotocin (STZ) in B, C and D groups. The rats in C and D groups were gavaged with L-glycine and L-arginine in dose of 200 mg.kg(-1).d(-1), respectively. The glucose content of the back skin tissue was determined for five rats in each group eight weeks after STZ administration. Deep partial thickness scalding of 20% TBSA was engendered on the back in the other 80 rats. The wound area, wound healing rate, and microvascular density with CD34 immunohistochemistry staining were determined on 3rd, 7th, 14th, and 21st post scalding days (PSDs), In addition, the amount of nitric oxide (NO) released from the wound tissue and the tissue contents of vascular endothelial growth factor (VEGF) and transforming growth factor beta1 (TGF-beta1) from wound were determined at the above time points., Results: Compared to those in group B, the wound healing rate in group D increased significantly since the 7th PSD [(44.10 +/- 3.50)%, P < 0.05], and the wound MVD value was increased significantly at all postburn time points. Furthermore, the levels of VEGF, NO and TGF-beta1 in the wound tissue was also increased significantly, while the glucose content in the cutaneous tissue was decreased to (1.380 +/- 0.120) mg/g., Conclusion: L-arginine supplementation could be beneficial to the angiogenesis in the burn wound of the rats with diabetes, as well as to wound healing by increasing the synthesis and the release of VEGF, NO and TGF-beta1 from burn wound and by decreasing the glucose content in the cutaneous tissue of diabetic rats.

Objective: To investigate the safety and the clinical effect of the tangential excision of the patients with deep partial thickness burn within 24 postburn hours (PBHs)., Methods: Twelve patients with deep partial thickness burn with the indication for tangential excision, the operation was carried out within 24 PBHs. These patients were designated as group A. Another group of fourteen patients with similar conditions undergoing tangential excision during 4 - 6 PBDs were designated as group B. The amount of fluid infusion during shock stage, the shock signs, the vital signs during recovery period, the urine output, as well as the healing time were compared between the two groups., Results: There was no obvious difference in the amount of fluid infusion and the shock signs between the two groups. There were evident differences in the body temperature and heart rate during recovery period, with the urine output increased dramatically during shock stage in group A when compared with those in group B (P < 0.05-0.01). The average wound healing days in group A were less than that in group B (P < 0.01)., Conclusion: Tangential excision within 24 PBHs was applicable and safe for the patients with deep partial thickness burn, and wound healing time was thus shortened.

Objective: To evaluate the effects of postburn dietary supplementation of arginine (Arg), omega-3 polyunsaturated fatty acid (omega-3PUFA) and glutamine (Glu) on the metabolism, immunology and wound healing in scalded rats., Methods: Thirty Sprague-Dawley (SD) rats inflicted with 30% total body surface area deep partial thickness scald on the back after the gastrostomy catheter was placed were employed as the model. The rats were randomly divided into A and B groups, and all of them received continuous isonitrogenous (25% protein, 12% fat, 63% carbohydrate), isocaloric (175 kcal/kg/day), and isovolemic intragastric tube feedings. The contents of Arg, omega-3PUFA, Glu in the dietary of B group were enriched. The parameters were measured on the 10th day after injury, including the response of spleen cells to ConA, the plasma levels of PGE(2), IL-2, albumin, transferrin, glucagons, cortisol in blood, the urinary content of vanillylmandelic acid (VAM) in 24-hour urine, the content of hydroxyproline, the ratio of type I to type III collagen in burn wounds, and the nitrogen content in the liver and in the jejunal mucosa, as well as the weight changes, skin delayed hypersensitivity test, and wound healing time., Results: It was revealed that the serum level of albumin, the nitrogen content in the liver and in the jejunal mucosa were obviously higher in B than those in A group. At the same time, there was no statistical difference in the plasma levels of cortisol and glucagons and urinary content of VAM between the two groups, nor in body weight changes. Meanwhile, the response of spleen cells to ConA and the skin delayed hypersensitivity induced by DNFB 14 days after injury in group B were also enhanced compared with those in group A. Although the expression of PGE2 from peritoneal macrophages was lower, the content of hydroxyproline from burn wounds in group B was significantly higher than that in group A, and the ratio of type l to type III collagen in group B was significantly lower than that in group A. Compared with group A, the wound healing time in group B was significantly shortened (P < 0.05)., Conclusion: The low-fat and high-protein feeding diet with enriched arginine, omega-3 PUFA, glutamine could benefit the nutritional status after burn injury, thus improve the immunological function and promote wound healing.

Objective: To study the proliferation-inhibiting and apoptosis-inducing effects of advanced glycation end products (AGE) modified human serum albumin (AGE-HSA) on human vein endothelial cells., Methods: Human umbilical vein endothelial cells ECV304 were cultured in vitro with AGE-HSA of the concentrations of 12.5, 25, 50, 100, and 200 micro g/ml for 6, 12, 24, or 48 hour, then 20 micro l of 5 mg/ml MTT were added and the optical density (OD) at each time point was determined. Another ECV304 cells were cultured with AGE-HAS for 2, 4, or 8 days and then were stained with trypan blue to calculate the number of dead cells so as to calculate the proliferation-inhibiting rate. Another ECV304 cells were cultured with AGE-HAS for 6, 12, 24, or 48 hours and then stained with annexin V Fitc and propidium iodide (PI). Flow cytometry was used to calculate the annexin V Fitc positive cells (early and middle stage apoptotic cells) and Annexin V Fitc/PL positive cells (late apoptotic cells). Inverted microscope, transmission electron microscope, and fluorescence microscope were used to observe the histological changes of apoptotic cells. FCV304 cells incubated with HSA of the above-mentioned and without addition of the other agents concentrations were used as controls., Results: The OD values of ECV304 cells cultured for 48 h with low concentrations (12.5, 25, and 50 micro g/ml) of AGE-HSA were not significantly different from those of the control (1.104 +/- 0.080, 1.098 +/- 0.097 and 1.059 +/- 0.122 VS. 1.159 +/- 0.088, all P > 0.05). The OD values of ECV304 cells cultured with low concentrations of AGE-HSA for 4 days and 6 days were significantly lower than those in the control group. The OD values of ECV304 cells cultured with high concentrations (100 and 200 micro g/ml) of AGE-HSA for 6 - 48 hours decreased to 0.117 +/- 0.033 and 0.081 +/- 0.020 in comparison with that of the control group (P < 0.01). Flow cytometry and fluorescence microscopy showed higher proportions of apoptotic cells among the ECV304 cells cultured with high concentrations of AGE-HAS than among the control cells at each time point (P < 0.01). The numbers of cells in the control group exponentially increased after culture for 2, 4, and 6 days. The number of cells cultured with low concentrations of AGE-HAS for 2 days was not significantly different from that of the control group (P > 0.05), however, the numbers of cells cultured with low concentrations of AGE-HAS for 4 and 6 days were significantly lower than those of the control group (both P < 0.01). The numbers of cells cultured with 100 or 200 micro g/ml AGE-HAS for 2 days were significantly lower than those of the control group (both P < 0.01) with a proliferation-inhibiting rate of 39.56% +/- 2.82% and 60.32% +/- 4.51% respectively. The apoptotic rates in cells cultured with low concentrations of AGE-HAS for 48 hours were not significantly different from those in the control group. The apoptotic rates in cells cultured with 100 or 200 micro g/ml AGE-HAS for 6, 12, 24, or 48 hours were significantly higher than those in the control group (all P < 0.01). The apoptotic rates in 200 micro g/ml group at different time points were significantly higher than those in the 100 micro g/ml group (P < 0.05 or 0.01). The apoptotic rate and number of apoptotic cells increased along with the increase of culture time and concentration of AGE-HAS. Microscopy showed morphological changes among the cells cultured with 100 micro g/ml AGE-HAS for 6, 12, 24, and 48 hours and the numbers of apoptotic cells, mainly late apoptotic cells, and dead cells increased remarkably since the cells were cultured for 48 hours., Conclusion: AGE-HSA inhibits the proliferation of vascular endothelial cells and induces apoptosis in dose and time dependent manner. AGE modification-induced pathobiological cascade may be involved in the pathogenesis of impaired wound healing in diabetes by the mechanism of angiogenesis retardation.