Angiogenin expression in burn blister fluid: Implications for its role in burn wound neovascularization

Deep partial thickness burn (DPTB) wound fluids have a greater propensity for establishing neovascularization than did superficial partial thickness burn (SPTB) wound fluids in our previous study. To investigate the factors responsible for this activity, cytokine array and enzyme‐linked immunosorbent assay were used to perform an expression analysis of angiogenic factors in burn fluid. Although present in approximately equal amounts in both SPTB and DPTB blister fluids from burn patients, angiogenin does appear to be involved in the ability of DPTB blister fluid to promote neovascularization in vitro and in vivo. Angiogenin alone was sufficient to induce endothelial differentiation of circulating angiogenic cells (CAC) without vascular endothelial growth factor A involvement. In addition, angiogenin was positively associated with CAC differentiation in the burn blister fluid. Blocking the effect of angiogenin in burn blister fluids resulted in a significant reduction of endothelial cell proliferation, CAC differentiation, and new blood vessels formation in vivo. Moreover, immunohistochemistry revealed that high angiogenin expression colocalizes with high vascularity in human burn wounds at day 7, further supporting our hypothesis that angiogenin is involved in burn wound neovascularization.     

Human beta defensin is absent in burn blister fluid

Defensins are a family of cationic antimicrobial peptides that participate in innate host defence. Human beta defensin-2 (HBD-2) is produced by human keratinocytes, and has a potent bactericidal activity against a wide spectrum of microorganisms. We have recently shown that expression of HBD-2 is present in normal skin and lost in the full-thickness burn wound. Defensins have been found in the blister fluid of chronic wounds. Our study was designed to examine blister fluid from partial-thickness burns for defensin content. Fluid from five patients was collected from partial-thickness burn blisters, and then analysed by sandwich Enzyme-Linked Immunosorbent Assay (ELISA) with a monoclonal antibody and rabbit polyclonal antibody to HBD-2. The assay was validated against a Western blot assay for HBD-2 in samples of bronchoalveolar lavage fluid from patients with inflammatory lung disease. No HBD-2 was detectable in any of the burn blister fluids analysed. HBD-2 is lost in the full-thickness burn wound, and we have now demonstrated its absence in burn blister fluid. This finding represents evidence of a host defence defect within the burn wound and suggests a possible therapeutic role for antimicrobial peptides in the management of burn wounds.     

Cryopreserved cadaveric allografts for treatment of unexcised partial thickness flame burns: clinical experience with 12 patients

Partial thickness burns (PTB) usually heal within 3 weeks. Prevention of infection and desiccation of the wounds are crucial for optimal healing. Early tangential excision of the burn eschar and allografting prevent deepening of the burns, and are therefore advocated for treatment with the best functional and aesthetic results. For superficial partial thickness burns (SPTB) conservative use of topical antimicrobial agents with frequent dressing changes are implemented. We compared the conservarive treatment for PTBs and SPTBs to grafting cryopreserved cadaveric allografts with no prior excision.

Twelve patients with flame PTB areas were allografted after mechanical debridement without excision of the burn wounds. The allografts were cadaveric skin cryopreserved by programmed freezing and stored at −180°C for 30–48 months. Matching burns for depth and area were treated with silver sulfadiazine (SSD) one to two times daily until healing or debridement and grafting were required.

It was found that 80 per cent of the cryopreserved allografts adhered well and 76 per cent of the treated areas healed within 21 days, whereas only 40 per cent of the SSD-treated burns healed within 21 days.

Partial thickness burns can be treated successfully with viable human allografts (cryopreserved cadaveric skin) with no prior surgical excision. The burn wounds heal well within 3 weeks. For deep partial thickness burns (DPTB) treatment with allografts has no advantage if they have not been previously excised.     

Conservative surgical debridement as a burn treatment: Supporting evidence from a porcine burn model

In thermal deep‐dermal burns, surgical debridement is normally used in conjunction with skin grafting or skin substitutes and debridement alone as a burn treatment is not usually practiced. The current study addresses whether or not debridement alone would enhance burn wound healing on small deep‐dermal‐partial thickness burns. This was a prospective and blinded experimental trial using a porcine deep‐dermal‐partial thickness burn model. Four burns, approximately 50 cm² in size, were created on each of eight pigs. Two burns from each pig were immediately surgically debrided and the other two were not debrided as the internal control. Hydrate gel together with paraffin gauze were used to cover the burns for four pigs and silver dressings for the other four. Clinical assessment of wound healing was conducted over a 6‐week period. Skin samples were collected at the end of the experiment and histopathological evaluation was performed. The results show thinner scar formation and lower scar height in the debrided compared with nondebrided wounds in the hydrate gel/paraffin gauze groups. There were no statistically significant differences in wound healing assessment between the debrided and nondebrided wounds dressed with silver dressings. This study provides supporting evidence that immediate debridement with an appropriate dressing and without skin grafting may promote wound healing, suggesting its potential benefit for clinical patients.     

几种深Ⅱ度烧伤创面处理方法的回顾及改善创面微循环的初步实验研究

目的回顾性分析几种深Ⅱ度烧伤创面的修复方法,探讨改善创面微循环对创面愈合的意义. 方法 (1)对于笔者单位烧伤患者的深Ⅱ度创面,应用削痂疗法治疗614例、磨痂疗法治疗32例、清创后异体皮覆盖86例、外用磺胺嘧啶银后创面暴露1 836例、外用中药京万红烫伤膏包扎治疗408例.统计、分析各种疗法的治疗效果.(2)制作大鼠深Ⅱ度烫伤模型.伤后5 min内分别由其尾静脉注入等渗盐水(对照组,10只)、巴曲酶(治疗组,10只),创面均外用磺胺嘧啶银.测定两组大鼠伤前及伤后0.5-72.0 h的创面皮肤血流灌注单位,计算其伤后14、18 d的创面愈合率、收缩率及创面愈合时间.用组织学方法观察两组大鼠创面愈合后的皮肤毛囊数. 结果 (1)削痂疗法术后2-3周创面愈合,其中烧伤总面积50%～79%TBSA的患者治愈率94.8%,总面积80%～98%TBSA者治愈率93.4%.磨痂疗法磨痂+异体皮覆盖术后(13.8±2.1)d创面愈合,无瘢痕形成.清创后异体皮覆盖其中82例患者术后(18.0±2.3)d创面愈合.外用磺胺嘧啶银后暴露其中1 658例患者用药后(26.0±3.2)d痂下愈合.外用京万红烫伤膏后包扎患者多有细菌感染,其中下肢创面愈合时间为(26.0±2.8)d.(2)治疗组大鼠伤后2.0-72.0 h创面局部血流灌注单位均明显高于对照组(P<0.01).伤后14、18 d,治疗组创面愈合率明显高于对照组(P<0.01),但两组创面收缩率接近(P>0.05).治疗组创面愈合时间短于对照组(P<0.01).伤后30 d,对照组大鼠真皮层中残存少量毛囊,数量明显少于治疗组(P<0.01). 结论深Ⅱ度烧伤后早期采用削痂、磨痂或清创后覆盖异体皮的方法处理创面,可减轻感染、缩短疗程、提高治愈率和愈合质量.使用巴曲酶可改善深Ⅱ度烧伤创面微循环,加快愈合速度.     

Wireless microcurrent stimulation improves blood flow in burn wounds

RationaleSkin breakdown, as in wounds, leads to an electric potential, defined as current of injury with the intent of wound closure. Burn wounds are defined by different zones of perfusion having a direct influence on further therapy (e.g. conservative management or skin grafting). We studied immediate, quantifiable effects of electric stimulation on skin perfusion in burn wounds.MethodWireless Microcurrent Stimulation (WMCS) was utilised as an adjunct therapeutic modality in 10 patients with partial thickness burn wounds. Microcirculation in the skin was quantified with a Laser Doppler (LDI) before and after WMCS treatment. We included a control group of 10 healthy individuals.ResultsA single application of WMCS significantly increased mean flow, velocity and subsequently, haemoglobin and oxygen saturation in partial thickness burn wounds. In healthy skin these parameters increased, but were far less pronounced than in thermally injured skin.ConclusionThis study revealed, for the first time that non-contact WMCS improves blood flow in critically perfused partial thickness burn wounds without disturbing the wound or systemically affecting the patient and may represent a promising adjunct tool in burn treatment, with the potential of faster healing by enhanced perfusion of burn wounds and reduction of the zone of stasis.Level of evidence: III     

荷负电气溶胶治疗Ⅱ度烧伤创面的临床效果及病理学观察

目的观察荷负电气溶胶(下称气溶胶)治疗Ⅱ度烧伤创面的效果。方法选择单纯浅Ⅱ、深Ⅱ度烧伤患者,随机分为:(1)气溶胶组:浅Ⅱ度180例、深Ⅱ度100例,伤后6h~2d开始用气溶胶治疗创面,l~2次/d,1.5h/次。(2)对照组:浅Ⅱ、深Ⅱ度患者各30例,常规治疗。(3)自身对照组:浅Ⅱ、深Ⅱ度患者各10例,同上用气溶胶治疗,但同一患者部分创面覆盖无菌金属片屏蔽气溶胶(屏蔽组),部分创面不屏蔽(非屏蔽组)。观察气溶胶治疗过程中患者创面的大体变化,治疗前后进行创面细菌培养,并监测其肝、肾功能及血生化指标有无改变。记录各组患者创面愈合时间。另制作深Ⅱ度烫伤大鼠模型,同前分为气溶胶组和对照组并治疗。取两组大鼠治疗前及治疗后1、2、3周的创面组织标本,作病理学观察。结果气溶胶治疗后患者创面渗出少,治疗前后均无细菌生长。总体来讲,气溶胶治疗前后患者肝、肾功能及血生化指标无明显改变。气溶胶组患者浅Ⅱ度创面伤后(6.3±1.6)d愈合,深Ⅱ度创面(15.1±3.1)d愈合,明显短于对照组相同深度创面[(11.3±1.4)、(21.2±1.4)d,P<0.01]。自身对照组中,相同烧伤深度的非屏蔽组与屏蔽组比较,创面愈合时间也明显缩短(P<0.01)。病理学检查显示,气溶胶组大鼠治疗后第3周皮肤结构已基本恢复正常,而对照组此时恢复较差。结论气溶胶能有效促进Ⅱ度烧伤创面的愈合且使用安全。     

Differential angiogenic and proliferative activity of surgical and burn wound fluids

BACKGROUND: Invasive surgical wounds exhibit the rapid production of a robustly proangiogenic environment. To compare the immediate angiogenic environment of wounds of different types, the angiogenic activity of fluid derived from burn injuries and wounds confined to the dermis was examined and compared with that of deeper surgical wounds. METHODS: The angiogenic activity of surgical wound fluid (SWF) (n = 7), skin graft wound fluid (SGF) (n = 3), and burn wound fluid (BWF) (n = 4) was assessed by measuring endothelial cell (EC) proliferative activity, EC chemotactic activity, and angiogenic activity in the rat corneal assay. The fibroblast growth factor-2 (FGF-2) level of each wound fluid was determined by enzyme-linked immunosorbent assay. RESULTS: SWF exhibited significant EC proliferative activity, SGF exhibited intermediate activity, and BWF displayed no EC proliferative activity. Seventy-one percent of SWF samples, 33% of SGF, and 0% of BWF contained significant EC chemotactic activity. Each wound fluid sample that demonstrated significant chemotactic activity also evoked a positive corneal angiogenic response. SWF contained 914 +/- 170 pg/mL of FGF-2, whereas SGF and BWF contained just 164 +/- 54 pg/mL and 37 +/- 7 pg/mL of FGF-2, respectively. CONCLUSION: The results suggest that injuries confined to the dermis, whether thermal or excisional, elicit a less robust initial angiogenic stimulus than deep surgical wounds.     

Comparative study of conventional and topical heparin treatment in second degree burn patients for burn analgesia and wound healing

Objective

To compare clinical outcome of topical conventional with topical heparin treatment in 2nd degree or partial thickness (PTB) burn patients.

Dendritic cells modulate burn wound healing by enhancing early proliferation

Adequate wound healing is vital for burn patients to reduce the risk of infections and prolonged hospitalization. Dendritic cells (DCs) are antigen presenting cells that release cytokines and are central for the activation of innate and acquired immune responses. Studies have showed their presence in human burn wounds; however, their role in burn wound healing remains to be determined. This study investigated the role of DCs in modulating healing responses within the burn wound. A murine model of full‐thickness contact burns was used to study wound healing in the absence of DCs (CD11c promoter‐driven diphtheria toxin receptor transgenic mice) and in a DC‐rich environment (using fms‐like tyrosine kinase‐3 ligand, FL‐ a DC growth factor). Wound closure was significantly delayed in DC‐deficient mice and was associated with significant suppression of early cellular proliferation, granulation tissue formation, wound levels of TGFβ1 and formation of CD31⁺ vessels in healing wounds. In contrast, DC enhancement significantly accelerated early wound closure, associated with increased and accelerated cellular proliferation, granulation tissue formation, and increased TGFβ1 levels and CD31⁺ vessels in healing wounds. We conclude that DCs play an important role in the acceleration of early wound healing events, likely by secreting factors that trigger the proliferation of cells that mediate wound healing. Therefore, pharmacological enhancement of DCs may provide a therapeutic intervention to facilitate healing of burn wounds.     

Debridement of burn wounds with a water jet surgical tool

A new instrument, the Versajet system, based on fluid jet technology has recently been advocated as an alternative to standard surgical excisional technique for burn wounds. In this paper we describe our experience with this tool, the technique employed as well as its clinical feasability for debriding partial thickness burn wounds. Seventeen patients were evaluated for clinical efficacy of debridement of their burn wounds using the Versajet system. Burn wound areas of between 0.5 and 5% total body surface (TBSA) involving the face, arm, hand, leg and foot underwent debridement using the Versajet system. The Versajet system was able to sufficiently debride superficial partial thickness and mid-dermal partial thickness wounds for subsequent placement of Biobrane. Deeper partial thickness wounds could be excised for successful autografting. The Versajet system demonstrated some particular advantage in the surgical treatment of superficial to mid-partial thickness burns in areas like the face, hand and foot which can often be difficult to reach and contour with conventional modalities.     

Cooling the burn wound: evaluation of different modalites

A study was undertaken to investigate the cooling and healing effect of different modalities: Melaleuca Alternifolia Hydrogel (Levtrade International (Pty) Ltd.) was compared with tap water as a coolant following application onto a fresh deep partial thickness hot water burn in a porcine model. Four identical circular scalds were created on the backs of 10 pigs. One wound was not treated and served as a control. The other 3 wounds were either cooled with tap water (15 degrees C) or had Melaleuca Hydrogel dressing applied immediately, or after a 30 min delay. Intradermal temperatures were monitored in all wounds: preburn, during the burn and at regular intervals for 1 h. The wounds were biopsied for histological assessment. These samples were repeated at 24 h and 3 weeks. The mean decrease in final temperature at 1 h was in comparison to the preburn temperature; control +0.44 degrees C (i.e. a temperature increase); water -7.82 degrees C; Melaleuca Hydrogel -3.87 degrees C; Melaleuca Hydrogel after 30 min delay -2.67 degrees C. Clinical and histological assessment at 21 days indicated more rapid healing in both the Melaleuca Hydrogel and water-cooled burns compared with the untreated controls. Effective cooling of the burn wound and an increased rate of wound healing was achieved by both repeated tap water compresses and by immediate or delayed application of Melaleuca Hydrogel. Cooling is an effective means to reduce tissue damage and increase wound healing.     

An ultrathin poly(l‐lactic acid) nanosheet as a burn wound dressing for protection against bacterial infection

Burn wounds are highly susceptible to bacterial infection due to impairment of the skin's integrity. Therefore, prevention of bacterial colonization/infection in the wound is crucial for the management of burns, including partial‐thickness burn injuries. Although partial‐thickness burn injuries still retain the potential for reepithelialization, the complication of wound infection severely impairs the reepithelialization even in such superficial burn injuries. We recently developed a biocompatible nanosheet consisting of poly(l ‐lactic acid) (PLLA). The PLLA nanosheets have many useful and advantageous biological properties for their application as a wound dressing, such as sufficient flexibility, transparency, and adhesiveness. We herein investigated the suitability of the PLLA nanosheets as a wound dressing for partial‐thickness burn wounds in mice. The PLLA nanosheets tightly adhered to the wound without any adhesive agents. Although wound infection with Pseudomonas aeruginosa in the controls significantly impaired reepithelialization of burn wounds, dressing with the PLLA nanosheet markedly protected against bacterial wound infection, thereby improving wound healing in the mice receiving partial‐thickness burn injuries. The PLLA nanosheet also showed a potent barrier ability for protecting against bacterial penetration in vitro. The ultrathin PLLA nanosheet may be applied as a protective dressing to reduce environmental contamination of bacteria in a partial‐thickness burn wound.     

表皮生长因子对大鼠深Ⅱ度烧伤创面愈合的影响

目的　进一步观察重组人表皮生长因子 (rhEGF)对深Ⅱ度烧伤创面愈合的促进作用。方法　采用大鼠深Ⅱ度烫伤模型 (以下称烧伤 ) ,创面分别外用rhEGF、肝素加rhEGF及等渗盐水。比较不同方式处理创面后的愈合时间 ,测定创面愈合率、创面含水量、羟脯氨酸 (OHP)含量及Ⅰ /Ⅲ型胶原比例 ,进行细胞DNA周期分析和组织学检查。　结果　外用rhEGF可使烧伤创面愈合时间缩短 2d,增加创面OHP含量 (P <0.0 5),降低Ⅰ /Ⅲ型胶原比例 (P <0.0 5),促进肉芽组织形成 ,加速细胞DNA复制 (P <0.0 5 )。加用肝素后可使创面愈合时间进一步缩短 2d,促进肉芽组织生长。伤后第 7天用药各组间比较 ,差异无显著性意义 (P >0.0 5)。　结论　外用rhEGF能明显促进深Ⅱ度烧伤创面愈合 ,加用肝素后效果更加显著 ,但早期使用rhEGF效果不明显     

A porcine deep dermal partial thickness burn model with hypertrophic scarring

We developed a reproducible model of deep dermal partial thickness burn injury in juvenile Large White pigs. The contact burn is created using water at 92 degrees C for 15s in a bottle with the bottom replaced with plastic wrap. The depth of injury was determined by a histopathologist who examined tissue sections 2 and 6 days after injury in a blinded manner. Upon creation, the circular wound area developed white eschar and a hyperaemic zone around the wound border. Animals were kept for 6 weeks or 99 days to examine the wound healing process. The wounds took between 3 and 5 weeks for complete re-epithelialisation. Most wounds developed contracted, purple, hypertrophic scars. On measurement, the thickness of the burned skin was approximately 1.8 times that of the control skin at week 6 and approximately 2.2 times thicker than control skin at 99 days after injury. We have developed various methods to assess healing wounds, including digital photographic analysis, depth of organising granulation tissue, immunohistochemistry, electron microscopy and tensiometry. Immunohistochemistry and electron microscopy showed that our porcine hypertrophic scar appears similar to human hypertrophic scarring. The development of this model allows us to test and compare different treatments on burn wounds.     

Relaxin induces vascular endothelial growth factor expression and angiogenesis selectively at wound sites

Relaxin is a reproductive hormone that has historically been characterized as being responsible for pubic ligament loosening and cervical ripening. Recently, relaxin has been associated with neovascularization of the endometrial lining of the uterus, potentially via specific induction of vascular endothelial growth factor. Previously conducted clinical studies using partially purified porcine relaxin have described relaxin's ability to stimulate the healing of ischemic wounds, suggesting that relaxin may also have angiogenic effects at sites of ischemic wound healing. In the present study, relaxin's angiogenic effects in the context of wound repair were tested in rodent models of angiogenesis and wound healing. Relaxin showed an ability to stimulate new blood vessel formation, particularly at ischemic wound sites, and to induce both vascular endothelial growth factor and basic fibroblast growth factor specifically in cells, presumably including macrophages, collected from wound sites. Resident macrophages collected from nonwound sites, such as the lung, did not show altered expression of these cytokines following relaxin administration. Because angiogenic wound cells are frequently macrophages, THP-1 cells, a cell line of monocyte lineage that binds relaxin specifically, were tested for and shown to induce vascular endothelial growth factor and basic fibroblast growth factor in response to relaxin. In conclusion, relaxin may be useful in the treatment of ischemic wounds by stimulating angiogenesis via the induction of vascular endothelial growth factor and basic fibroblast growth factor in wound macrophages.     

神经生长因子加速猪深Ⅱ度烧伤创面愈合的实验

目的 探讨神经生长因子(nerve growth factors，NGF)对猪烧伤创面愈合的影响。方法 小白家猪6只，用控温控压仪在其背部制成24个直径为2．5cm的深Ⅱ度创面，随机分为4组，每6个创面为1组，即等渗盐水对照组，NGF1、2．5、5μg／ml治疗组。治疗后3、5、9d进行组织学检查、羟脯氨酸测定、细胞DNA周期分析及各组创面愈合时间比较。结果 治疗组上皮增生活跃且上皮化较对照组提前；治疗组创面组织羟脯氨酸含量，均有一个先下降后升高的过程，尤其在第5天，与对照组相比明显下降；细胞DNA周期分析表明，治疗组在S期细胞数较对照组均有明显增多；创面愈合时间较对照组提前。结论 局部应用NGF能促进烧伤深Ⅱ度创面愈合。     

巴曲酶对深Ⅱ度烫伤创面微循环血流变化及愈合的影响

目的　探讨巴曲酶对大鼠烫伤早期创面淤滞带微循环血流变化及愈合过程的影响。　方法　Wistar雄性大鼠 2 0只 ,随机分为烫伤对照组及巴曲酶治疗组 ,在各组动物背部均造成 4cm× 4cm大小深Ⅱ度烫伤。分别于伤前、伤后 0 .5、2、4、6、12、2 4、72h测定创面局部皮肤血流量 ;于伤后立即、伤后 14、18d测定烫伤面积及残留创面面积 ;于伤后 30d将大鼠处死取材行组织学观察及毛囊计数。　结果　大鼠伤后 2 72h皮肤血流量进行性减少 ;与对照组相比 ,给予巴曲酶后皮肤血流量得到明显改善 ,创面愈合速度明显加快 ,愈合后皮肤附件明显增多。　结论　巴曲酶能逆转烧伤后创面淤滞带循环 ,加快创面愈合速度和提高皮肤愈合质量     

烫伤大鼠不同深度创面组织中表皮干细胞分布的初步研究

目的初步观察烫伤大鼠不同深度创面组织中表皮干细胞的分布情况。方法将32只SD大鼠分别造成Ⅰ、浅Ⅱ、深Ⅱ和Ⅲ度烫伤，伤后24h取创面组织标本，制作切片。采用细菌蛋白一生物素标记法(LSAB)进行免疫组织化学染色，以α2、β1整合素及角蛋白10(K10)作为一抗，观察不同创面组织中表皮干细胞的表达和分布情况。结果Ⅰ度烧伤创面组织中，K10阳性细胞分布于表皮的棘细胞层、颗粒层、透明层，α2、β1整合素阳性细胞分布于表皮基底层，数量多。浅Ⅱ度创面中，α2、β1整合素阳性细胞位于残留的基底层和皮肤附属器(主要是毛囊)中，数量较少。深Ⅱ度创面中，α2、β1整合素阳性细胞仅存在于真皮深层健存的皮肤附属器中，数量很少。Ⅲ度创面中，罕见α2、β1整合素阳性细胞。结论表皮干细胞在烧伤创面中的分布与烧伤深度有关，残存的表皮干细胞可能是创伤修复过程中再上皮化的细胞来源。     

Nano-silver modified porcine small intestinal submucosa for the treatment of infected partial-thickness burn wounds

Background and aimSilver has been widely used as a topical antimicrobial agent in burn wound care. In a previous study, we demonstrated the introduction of nano-silver particles to porcine small intestinal submucosa (NS-PSIS) led to significant enhancement in antibacterial property in repairing contaminated abdominal defect. In this study, we explored the efficacy of NS-PSIS in the treatment of Pseudomonas aeruginosa-infected partial-thickness burn wounds.Methods48 male Sprague-Dawley rats were divided into four groups of equal number. Standardized and reproducible Pseudomonas aeruginosa-infected partial-thickness thermal burns wound model were created using these rats. NS-PSIS, PSIS (porcine small intestinal submucosa) or lipido-colloid dressingss (Urgotul?) were tested for 14 days to assess their ability to heal the rats’ burn wounds. Control group was without any treatment after the establishment of infected burn-wound. The wound contraction rate, animal body weight change, histological examination, and the quantification of IL-6 and C-reactive protein (CRP) were measured to evaluate the healing effects.ResultsNS-PSIS significantly promoted wound healing and recovered the normal growth of rats. There were significantly lower expression levels of pro-inflammatory cytokine (IL-6) and CRP in NS-PSIS group as compared with the PSIS or Urgotul group in the treatment of infected partial-thickness burn wounds. Histological exams revealed significant less inflammatory cells infiltrating, more re-epithelization and neovascularization in NS-PSIS group. There were also less inflammatory cells infiltrations in the major organs in NS-PSIS group.ConclusionsNano-silver modified porcine small intestinal submucosa (NS-PSIS) can be used as a biological derivative dressing for the treatment of infected partial-thickness burn wounds.