The asynchronous dynamic changes and interrelationships between leukocyte composition and inflammatory markers and potential clinical significance in the early stage and sepsis stage in severe burns.

OBJECTIVE: The aim of this study is to investigate the dynamic changes and interrelationships between leukocyte components and inflammatory markers in the early stages and sepsis stage in severe burns, and explore their potential clinical significance. METHODS: This is a 5-year retrospective cohort study involving 107 patients with severe burns (the total body surface area of burn (TBSA) > 50%), in which, neutrophil count, lymphocyte count, monocyte count, the ratio of the product of monocyte and lymphocyte count to neutrophil count (MLPN), procalcitonin (PCT), C-reactive protein (CRP), capillary leakage index (CLI) and creatinine (Scr) were investigated. RESULTS: Within one week after injury, the leukocyte components and MLPN showed a V-shaped change, with a peak immediately after injury and a trough on the 4th or 5th day after injury, while CRP showed a continuous upward trend, and the leukocyte compositions of all patients were negatively correlated with CRP values. The counts of leukocytes components and CRP values in deceased patients were higher than those in surviving patients within 2 days after injury. In the resorption stage, although no significant difference in lymphocyte and monocyte counts between surviving and deceased patients was found, the monocyte and lymphocyte counts in deceased patients were lower than those in surviving patients on the 5th to 7th day after injury, while neutrophils counts and CRP values remained higher than those in surviving patients. And the dynamic changes of MLPN were consistent with those of leukocyte compositions and opposite to those of PCT values. Moreover, MLPN were negatively correlated with CRP, CLI, and Scr values in the early stage of severe burns. In sepsis stage, as the condition worsened, the values of CRP, PCT and neutrophil counts continuously increased with varying degree, while lymphocyte and monocyte counts, and MLPN showed continuously decrease, but rebounded to increase before death. And the occurrence of the trough of monocyte counts was earlier than that of lymphocyte counts, a negative correlation between neutrophil counts and PCT values was found. CONCLUSION: The results of this study revealed the dynamic interrelationships between leucocyte components and inflammatory indicators in the early stages and sepsis stage in severe burns, reflecting the different weightings of inflammatory responses and immune dysfunction in different disease stages and its correlation with outcomes, which providing useful clinical information for dynamic immunomodulatory therapy. Moreover, dynamic monitoring of MLPN value can provide timely information for clinical evaluation.

Dual gene-activated dermal scaffolds regulate angiogenesis and wound healing by mediating the coexpression of VEGF and angiopoietin-1.

The vascularization of dermal substitutes is a key challenge in efforts to heal deep skin defects. In this study, dual gene-activated dermal scaffolds (DGADSs-1) were fabricated by loading nanocomposite particles of polyethylenimine (PEI)/multiple plasmid DNAs (pDNAs) encoding vascular endothelial growth factor and angiopoietin-1 at a ratio of 1:1. In a similar manner, DGADSs-2 were loaded with a chimeric plasmid encoding both VEGF and Ang-1. In vitro studies showed that both types of DGADSs released PEI/pDNA nanoparticles in a sustained manner; they demonstrated effective transfection ability, leading to upregulated expression of VEGF and Ang-1. Furthermore, both types of DGADSs promoted fibroblast proliferation and blood vessel formation, although DGADSs-1 showed a more obvious promotion effect. A rat full-thickness skin defect model showed that split-thickness skin transplanted using a one-step method could achieve full survival at the 12th day after surgery in both DGADSs-1 and DGADSs-2 groups, and the vascularization time of dermal substitutes was significantly shortened. Compared with the other three groups of scaffolds, the DGADSs-1 group had significantly greater cell infiltration, collagen deposition, neovascularization, and vascular maturation, all of which promoted wound healing. Thus, compared with single-gene-activated dermal scaffolds, DGADSs show greater potential for enhancing angiogenesis. DGADSs with different loading modes also exhibited differences in terms of angiogenesis; the effect of loading two genes (DGADSs-1) was better than the effect of loading a chimeric gene (DGADSs-2). In summary, DGADSs, which continuously upregulate VEGF and Ang-1 expression, offer a new functional tissue-engineered dermal substitute with the ability to activate vascularization.

Nanosilver alleviates foreign body reaction and facilitates wound repair by regulating macrophage polarization. / 纳米银通过调控巨噬细胞极化以减轻异物反应并促进创面修复.

Foreign body reactions induced by macrophages often cause delay or failure of wound healing in the application of tissue engineering scaffolds. This study explores the application of nanosilver (NAg) to reduce foreign body reactions during scaffold transplantation. An NAg hybrid collagen-chitosan scaffold (NAg-CCS) was prepared using the freeze-drying method. The NAg-CCS was implanted on the back of rats to evaluate the effects on foreign body reactions. Skin tissue samples were collected for histological and immunological evaluation at variable intervals. Miniature pigs were used to assess the effects of NAg on skin wound healing. The wounds were photographed, and tissue samples were collected for molecular biological analysis at different time points post-transplantation. NAg-CCS has a porous structure and the results showed that it could release NAg constantly for two weeks. The NAg-CCS group rarely developed a foreign body reaction, while the blank-CCS group showed granulomas or necrosis in the subcutaneous grafting experiment. Both matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were reduced significantly in the NAg-CCS group. The NAg-CCS group had higher interleukin (IL)-10 and lower IL-6 than the blank CCS group. In the wound healing study, M1 macrophage activation and inflammatory-related proteins (inducible nitric oxide synthase (iNOS), IL-6, and interferon-|γ (IFN-|γ)) were inhibited by NAg. In contrast, M2 macrophage activation and proinflammatory proteins (arginase-1, major histocompatibility complex-II (MHC-II), and found in inflammatory zone-1 (FIZZ-1)) were promoted, and this was responsible for suppressing the foreign body responses and accelerating wound healing. In conclusion, dermal scaffolds containing NAg suppressed the foreign body reaction by regulating macrophages and the expression of inflammatory cytokines, thereby promoting wound healing.

Triage and Evaluation of Blast-Injured Patients in Wenling Liquefied Petroleum Gas Tanker Explosion.

On June 13, 2020, a liquefied petroleum gas tanker exploded in Wenling. Here, the authors describe the mass casualty emergency response to the explosion. The authors collected the medical records of 176 inpatients at 8 hospitals in Taizhou and Hangzhou. The 176 inpatients with blast injuries comprised 70 females and 106 males, with an average age of 45.48 ± 19.96 years, and more than half of the patients were farmers. They were transported to six hospitals distributed around the explosion site in Taizhou in the initial rescue period and were grouped according to their new injury severity score as having mild, moderate, severe, or extremely severe injuries. Most patients with severe and extremely severe injuries were admitted to a superior hospital for postsecondary triage. Forty-four patients experienced primary blast injuries, 137 experienced secondary blast injuries, 37 experienced tertiary blast injuries, and 40 patients experienced quaternary blast injuries. Multiple blast injuries were suffered by 62 patients. Most patients (95.45%) suffered external injuries, with the chest, extremities, and face as the main affected areas. Burns were diagnosed in 26 adults, of whom 15.38%, 19.23%, 7.70%, and 57.69% suffered mild, moderate, severe, and extremely severe cases. Sixteen burn patients suffered from burn-blast injuries. Upper limbs and the head/face/neck area, as exposed areas, were more likely to experience a burn injury. Inhalation was the main accompanying injury. Of the eight patients who died in the prehospital session, seven had burn injuries. This report on the accident and injury characteristics of an open-air LPG-related explosion will facilitate responses to subsequent catastrophes.

Efficacy and Safety of PL-5 (Peceleganan) Spray for Wound Infections: A Phase IIb Randomized Clinical Trial.

OBJECTIVE: To assess the safety and efficacy of antimicrobial peptide PL-5 (Peceleganan) spray in the treatment of wound infections. BACKGROUND: Antimicrobial peptide PL-5 spray is a novel topical antimicrobial agent. METHODS: We conducted a multicenter, open-label, randomized, controlled phase IIb clinical trial to evaluate the efficacy and safety of PL-5 spray, as compared with silver sulfadiazine, in patients with skin wound infections. The primary efficacy outcome was the clinical efficacy rate on the first day after ending the treatment (D8). The secondary efficacy outcome was the clinical efficacy rate on the fifth day posttreatment (D5), the bacteria clearance rate, and the overall efficacy rate at the mentioned 2 time points. The safety outcomes included adverse reactions and pharmacokinetic analysis posttreatment. RESULTS: A total of 220 patients from 27 hospitals in China were randomly assigned to 4 groups. On D8, the efficacy rate was 100.0%, 96.7%, 96.7% for the 1‰ PL-5, 2‰ PL-5, 4‰ PL-5 groups, respectively, as compared with 87.5% for the control group. The efficacy rate among the 4 groups was significantly different ( P <0.05). On D5, the efficacy rate was 100.0%, 93.4%, 98.3% for the 1‰ PL-5, 2‰ PL-5, 4‰ PL-5 groups, respectively, as compared with 82.5% for the control group. The efficacy rate among the 4 groups was significantly different ( P <0.05). The blood concentration of PL-5 was not detectable in pharmacokinetic analysis. No severe adverse event related to the application of PL-5 was reported. CONCLUSIONS: Antimicrobial peptide PL-5 spray is safe and effective for the treatment of skin wound infections. TRIAL REGISTRATION: ChiCTR2000033334.

The optimization of PLGA knitted mesh reinforced-collagen/chitosan scaffold for the healing of full-thickness skin defects.

Collagen-based scaffolds reveals promising to repair severe skin defects. The mechanical strength of collagen-based scaffold (CCS) limited its clinical application. Embedding poly(lactic-co-glycolic) acid (PLGA) knitted mesh into CCS improves the mechanical strength of the scaffold. This study was conducted to optimize the configuration of PLGA knitted mesh-collagen-chitosan scaffold (PCCS), and explore possible mechanisms. PLGA knitted mesh was embedded in CCS through freeze-drying method. With the PLGA knitted mesh located at the bottom, middle, or both bottom and top layers of the CCS, three kinds of PCCS were developed. A full-thickness skin wound model was established in Sprague Dawley rats to evaluate the therapeutic effects of different PCCS against CCS. The properties and healing effect of the scaffolds were investigated. Several growth factors and chemotactic factors, that is, VEGF, PDGF, CD31, α-SMA, TGF-ß1, and TGF-ß3 were analyzed and evaluated. Re-epithelialization and angiogenesis were observed in all animal groups with the treatment of three kinds of PCCS scaffolds and the CCS scaffold (control). The protein and gene expression of VEGF, PDGF, CD31, α-SMA, TGF-ß1, and TGF-ß3 showed different dynamics at different time points. Based on the healing effects and the expression of growth factors and chemotactic factors, scaffold with the PLGA knitted mesh located at the bottom layer of the CCS demonstrated the best healing effect and accelerated re-epithelialization and angiogenesis among all the scaffolds evaluated. PCCS with the PLGA mesh located in the bottom layer of the scaffold accelerated wound healing by creating a more supportive environment for re-epithelialization and angiogenesis.

Heme oxygenase-1 induction mitigates burn-associated early acute kidney injury via the TLR4 signaling pathway.

OBJECTIVES: Early acute kidney injury (AKI) after burn contributes to disastrous prognoses for severely burned patients. Burn-induced renal oxidative stress and secondary proinflammatory mediator release contribute to early AKI development, and Toll-like receptor (TLR) 4 regulates inflammation. Heme oxygenase-1 (HO-1) is a stress-responsive enzyme that plays a vital role in protecting against ischemia-induced organ injury via its antioxidant properties and regulation of inflammation. We investigated the potential effect of HO-1 induction in preventing burn-induced early AKI and its related mechanism. METHODS: A classic major-burn rat model was established using a 100 °C water bath, and hemin was injected intraperitoneally immediately after the injury to induce HO-1. Histological staining and blood tests were used to assess AKI progression based on structural changes and function. Renal levels of HO-1, oxidative stress, proinflammatory mediators and TLR4-related signals were detected using ELISA, immunostaining, qRT-PCR, and western blotting. The selective TLR4 inhibitor TAK242 and TLR4 inducer LPS were introduced to determine the roles of HO-1 in burn-related renal inflammation and the TLR4 pathway. RESULTS: Hemin improved burn-induced renal histological damage and dysfunction, and this beneficial effect was related to reduced renal oxidative stress and the release of proinflammatory mediators, such as tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1ß, IL-6 and intracellular adhesion molecule-1 (ICAM-1). Hemin downregulated the expression of TLR4 and the subsequent phosphorylation of IKKα/ß, IκBα, and NF-κB p65;. TAK242 exerted an effect similar to but weaker than hemin; and LPS reversed the antiinflammatory effect of hemin and the regulation of TLR4 signals. These results suggested that the TLR4 signaling pathway mediated the HO-1-facilitated regulation of renal inflammation after burn. CONCLUSION: The present study demonstrated that HO-1 induction prevented burn-induced early AKI by targeting renal inflammation, which was mediated via regulation of the TLR4/NF-κB signaling pathway.

Modified single-hair follicular unit grafting to esthetically restore eyelashes in Asians.

BACKGROUND: Eyelashes play an important role in the perception of beauty and protection of eyeballs. The outcome of eyelash restoration varies and mainly depends on the surgeon's technique and no standard procedure exists. AIMS: To evaluate the effect of modified single-hair follicular unit grafting to esthetically restore eyelashes and provide a potential alternative of standard procedure. PATIENTS AND METHODS: A total of 34 patients with sparse or partially absent eyelashes who underwent modified procedure were included. Single-hair grafts were harvested from the donor site (post-auricular, nape, frontal hairline area). Grafts were transplanted with 23 gauge needle and fine forceps in the modified procedure. The patients were followed for a mean of 12 months after surgery. RESULTS: All patients were satisfied with the result 12 months after the surgery. An average of 46.5 grafts (34-68) were transplanted in each upper eyelid. The mean graft survival rate after 1 year was 87.2% (84%-92%). Of the 34 patients, three patients received a second session to achieve a denser appearance. No significant complication as trichiasis, infection, scarring, or eyeball injury occurred. CONCLUSION: This modified single-hair follicular unit grafting is a good alternative for esthetic eyelash restoration with good cosmetic results, relative easy maintenance, lack of complications, and long-term patient satisfaction.

Consensus on the application of negative pressure wound therapy of diabetic foot wounds.

Because China is becoming an aging society, the incidence of diabetes and diabetic foot have been increasing. Diabetic foot has become one of the main health-related killers due to its high disability and mortality rates. Negative pressure wound therapy (NPWT) is one of the most effective techniques for the treatment of diabetic foot wounds and great progress, both in terms of research and its clinical application, has been made in the last 20 years of its development. However, due to the complex pathogenesis and management of diabetic foot, irregular application of NPWT often leads to complications, such as infection, bleeding and necrosis, that seriously affect its treatment outcomes. In 2020, under the leadership of Burns, Trauma and Tissue Repair Committee of the Cross-Straits Medicine Exchange Association, the writing group for 'Consensus on the application of negative pressure wound therapy of diabetic foot wounds' was established with the participation of scholars from the specialized areas of burns, endocrinology, vascular surgery, orthopedics and wound repair. Drawing on evidence-based practice suggested by the latest clinical research, this consensus proposes the best clinical practice guidelines for the application and prognostic evaluation of NPWT for diabetic foot. The consensus aims to support the formation of standardized treatment schemes that clinicians can refer to when treating cases of diabetic foot.

Locally activated mitophagy contributes to a "built-in" protection against early burn-wound progression in rats.

AIMS: Deep burn-wounds undergo a dynamic progression in the initial or periburn area after insults, and the zone of stasis is the crucial region suffering the deterioration, considered as salvageable. Few studies explored the role of mitochondria in this process. This study is to clarify a possible "built-in" protection of mitophagy. MAIN METHODS: A classic "comb" scald rat model was established. Histological and blood-flow observation were processed based on hematoxylin-eosin staining and laser analysis. Oxidative and apoptotic status were analyzed by commercial kits. Transmission-electron microscope, immunofluorescence staining, and western blot were applied to detect the mitophagy in the zone of stasis and potential regulators. Adenovirus-based gene-silence contributed to determine the role of HIF-1α as a regulatory mediator. KEY FINDINGS: We found that burn-caused typical ischemia and histological deterioration in the zone of stasis, in parallel with increases in oxidative stress and apoptosis. Mitochondrial damage was involved in the aforementioned changes. Furthermore, we detected mitophagy in burn-wounds, which was contradictory to the burn-wound conversion. HIF-1α expression was closely related to the level of mitophagy, while BNIP3 and PARKIN are involved downstream. SIGNIFICANCE: We demonstrate that burn-induced mitochondrial impairment contributes to the mobilization of injurious mechanisms in the zone of stasis and that mitophagy provides a beneficial way to protect against burn-wound progression via the elimination of damaged mitochondria. Our findings offer insights into mitochondrial quality control in burn-wound progression and suggest the novel concept that HIF-1α may be a therapeutic target due to its possible regulation on BNIP3- or PARKIN-mediated mitophagy.

A Retrospective Multicenter Study of 1898 Liquefied Petroleum Gas-Related Burn Patients in Eastern China From 2011 to 2015.

Liquefied petroleum gas (LPG) is a widely used environment-friendly fuel. Previous studies have shown an increasing number of LPG-related burns. Our study was designed to evaluate the epidemiologic pattern of these injuries and provide recommendations for burn prevention. This retrospective study included all patients with LPG-related burns from eight burn centers in Zhejiang Province, China between 2011 and 2015. Database variables included patient demographics, accident characteristics, and injury characteristics. The association between different categorical variables was identified using the chi-square test. And the association between two or more means of quantitative variables was analyzed by the one-way analysis of variance or t-test. A total of 1898 patients were included, 47.31% were males and 52.69% were females. The predominant age group was 31 to 70 years (74.50%), and the majority were poorly educated and the incidence peaked from June to September. The most common place of occurrence was home (74.08%) and gas leak (96.52%) was the most common cause. The four limbs (43.33%) were the most frequently affected areas; the mean burn area was 25.19 ± 20.97% of the total body surface area and most patients (46.89%) suffered from moderate burns. The mean length of hospital stay was 17.66 ± 16.55 days and the majority of patients (89.36%) recovered with a 0.84% mortality rate. Our findings reflected that the increase in incidence rate was alarming, and the causes resulting in LPG-related burns have not gained much attention yet. Therefore, this calls for simple but strict measures aiming at each hazardous step during the use of LPG to prevent these burn injuries.

Accumulation of Advanced Glycation Endproducts and Subclinical Inflammation in Deep Tissues of Adult Patients With and Without Diabetes.

OBJECTIVES: Advanced glycation endproducts (AGEs) play a key role in the development of foot complications in people with diabetes. Skin autofluorescence (AF) might noninvasively determine tissue accumulation of AGEs. This study evaluated the association between skin AF and AGE contents in the deep tissues of those with diabetes and the further consequences of such contents. METHODS: Between September 2014 and September 2015, we studied 33 patients, with and without diabetes, who had received lower-limb amputations. Skin AF was measured. Artery, nerve and skin were harvested during surgery. AGE contents were quantified using high-performance liquid chromatography mass spectrometry and were located by immunohistochemistry staining. Inflammatory cells were also located by immunohistochemistry, immunofluorescence and scanning electron microscopy. RESULTS: Values of skin AF and AGE contents in artery, nerve and skin in patients with diabetes were higher than those in healthy patients. Skin AF was strongly affected by AGE contents in these tissues. AGE contents in various tissues were strongly correlated with each other. Differing AGEs were deposited in similar manners in the same tissues and were accompanied by inflammatory cells. CONCLUSIONS: AGE contents were strongly correlated with each other and were accompanied by inflammatory cells. Skin AF measurement could provide information about the systemic accumulation of AGEs.

Non-viral gene delivery systems for tissue repair and regeneration.

Critical tissue defects frequently result from trauma, burns, chronic wounds and/or surgery. The ideal treatment for such tissue loss is autografting, but donor sites are often limited. Tissue engineering (TE) is an inspiring alternative for tissue repair and regeneration (TRR). One of the current state-of-the-art methods for TRR is gene therapy. Non-viral gene delivery systems (nVGDS) have great potential for TE and have several advantages over viral delivery including lower immunogenicity and toxicity, better cell specificity, better modifiability, and higher productivity. However, there is no ideal nVGDS for TRR, hence, there is widespread research to improve their properties. This review introduces the basic principles and key aspects of commonly-used nVGDSs. We focus on recent advances in their applications, current challenges, and future directions.

Rare Skin Fistulas Relating to Ascending Colonic Carcinoma: An Unusual Mode of Revelation.

Chronic or nonhealing wounds is a complex disease influenced by a multitude of factors, such as infection, ischemia, malnutrition, and diabetes and infrequently relates to retroperitoneal carcinoma. We present a case of an adenocarcinoma of ascending colon in a 68-year-old male who had lumbago and waist fistulas with retroperitoneal abscesses preceding other signs or symptoms of colonic malignancy. Supplemental information regarding the diagnosis and treatment of nonhealing wounds and colon carcinoma has also been included in the report. Adenocarcinoma of ascending colon is rarely associated with nonhealing wounds; nevertheless, it should be considered in cases with long-term healing complications. Precise diagnostic deliberation is crucial in the management and treatment of all chronic and long-term nonhealing lesions, and appropriately performed biopsies are essential to determine whether malignancy is the primary cause.

Five-year epidemiology of liquefied petroleum gas-related burns.

BACKGROUND: The incidence of liquefied petroleum gas (LPG)-related burns has increased over recent years, and it has become a serious public health issue in developing countries such as India and Turkey. This paper aims to investigate the epidemiological characteristics of LPG-related burns to provide assistance and suggestions for planning prevention strategies. METHODS: A 5-year retrospective study was conducted in patients with LPG-related burns admitted to the Department of Burns & Wound Care Center, Second Affiliated Hospital of Zhejiang University, College of Medicine, between 1st January 2011 and 31st December 2015. Information obtained for each patient included age, gender, education status, occupation, medical insurance, average hospital cost, length of hospital stay, monthly distribution of incidence, place of burns, mechanism of burns, extent of burns, site of burns, accompanying injuries, and treatment outcomes. RESULTS: For the first 4 years (2011-2014), the yearly incidence of LPG-related burns was at approximately 10% of all burns; however, in the fifth year (2015) alone, there was a surge to 26.94%. A total of 1337 burn patients were admitted during this period. Of these, 195 patients were admitted because of 169 LPG-related accidents; there were 11 accidents involving more than one victim. LPG-related burns occurred most frequently in patients aged 21-60 years (73.85%). The majority of injuries occurred from May to August (56.41%), and the most common place was home (83.08%, 162 patients). Gas leak (81.03%) was the main cause of LPG-related burns, followed by inappropriate operation (7.69%) and cooking negligence (2.05%). The mean burn area was 31.32±25.40% of TBSA. The most common sites of burns were the upper extremities (37.47%), followed by the head/face and neck (24.80%) and lower extremities (19.95%). The most common accompanying injuries included inhalation injury (23.59%), shock (8.71%), and external injury (7.18%). The average hospital stay was 22.90±19.47days (range 2-84 days). Only 48 patients (24.62%) had medical insurance, while 124 patients (63.59%) had no medical insurance. The average hospital cost of the no medical insurance group was significantly higher (p<0.0001) than that of the medical insurance group. In addition, 72.73% of patients who left against medical advice (LAMA) were uninsured. The number of patients who recovered at our hospital was 165 (84.62%), while 22 patients (11.28%) LAMA. The overall mortality rate was 4.10% (8 patients). CONCLUSION: Our study shows that the exponential increase in LPG-related burns is alarming. This calls for rigorous precautions. Because gas leak was the main cause of LPG-related burns, any part of LPG stove system that shows signs of weathering should be replaced regularly. In addition, we also found that most of the LAMA patients were uninsured. Thus, comprehensive medical insurance should be involved early in the recovery process to assure a safe and adequate discharge.

Silver nanoparticle loaded collagen/chitosan scaffolds promote wound healing via regulating fibroblast migration and macrophage activation.

Treatment of full-thickness skin defects poses significant clinical challenges including risk of infection and severe scaring. Silver nanoparticle (NAg), an effective antimicrobial agent, has provided a promising therapeutic method for burn wounds. However, the detailed mechanism remains unknown. Hence, we constructed a metallic nanosilver particles-collagen/chitosan hybrid scaffold (NAg-CCS) and investigated its potential effects on wound healing. In vitro scratch assay, immunofluorescence staining and antibacterial activity of the scaffold were all studied. In vivo NAg-CCS was applied in full-thickness skin defects in Sprague-Dawley (SD) rats and the therapeutic effects of treatment were evaluated. The results showed that NAg at a concentration of 10 ppm accelerated the migration of fibroblasts with an increase in expression of α-smooth muscle actin (α-SMA). Furthermore, in vivo studies showed increased levels of pro-inflammatory and scar-related factors as well as α-SMA, while markers for macrophage activation were up-regulated. On day 60 post transplantation of ultra-thin skin graft, the regenerated skin by NAg-CCS had a similar structure to normal skin. In summary, we demonstrated that NAg-CCS was bactericidal, anti-inflammatory and promoted wound healing potentially by regulating fibroblast migration and macrophage activation, making it an ideal dermal substitute for wound regeneration.

Astaxanthin protects against early burn-wound progression in rats by attenuating oxidative stress-induced inflammation and mitochondria-related apoptosis.

Burn-wound progression can occur in the initial or peri-burn area after a deep burn injury. The stasis zone has a higher risk of deterioration mediated by multiple factors but is also considered salvageable. Astaxanthin (ATX), which is extracted from some marine organisms, is a natural compound with a strong antioxidant effect that has been reported to attenuate organ injuries caused by traumatic injuries. Hence, we investigated the potential effects of ATX on preventing early burn-wound progression. A classic "comb" burn rat model was established in this study for histological and biological assessments, which revealed that ATX, particularly higher doses, alleviated histological deterioration in the stasis zone. Additionally, we observed dose-dependent improvements in oxidative stress and the release of inflammatory mediators after ATX treatment. Furthermore, ATX dose-dependently attenuated burn-induced apoptosis in the wound areas, and this effect was accompanied by increases in Akt and Bad phosphorylation and a downregulation of cytochrome C and caspase expression. In addition, the administration of Ly 294002 further verified the effect of ATX. In summary, we demonstrated that ATX protected against early burn-wound progression in a rat deep-burn model. This protection might be mediated by the attenuation of oxidative stress-induced inflammation and mitochondria-related apoptosis.

The progress and challenges for dermal regeneration in tissue engineering.

Wound healing is an inherent response resulting in the restoration of tissue integrity. It is a complex process involving cell migration, proliferation, differentiation, apoptosis, and the synthesis and remodeling of the extracellular matrix (ECM). The dermal tissue is an important component of skin that acts as a connecting link between the epidermis and hypodermis. The appearance of scars and contractures after autologous split-thickness skin transplantation or single epidermis diaphragm transplantation for full skin defects indicates that the dermal tissue plays an important role in skin regeneration. Theoretically, dermis cannot regenerate like the liver, bone and epidermis after being destroyed by burns or avulsion. Scarring is hard to avoid during the process of natural healing. However, if the dermis could be reconstructed perfectly, this would be a breakthrough in the methods used for wound healing. In this review, we summarize recent research about dermal regeneration and discuss the probability of advances in the field. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1208-1218, 2017.

Hydrofluoric acid burns in the western Zhejiang Province of China: a 10-year epidemiological study.

BACKGROUND: Chemical burns caused by hydrofluoric acid (HF) frequently occur in the Western Zhejiang Province. This study aimed to investigate the epidemiological characteristics of HF burns within this region. METHODS: A 10-year retrospective analysis was conducted using data from all inpatients with HF burns. These patients were treated at the Department of Burns and Plastic Surgery at our hospital between January 2004 and December 2013. Information obtained for each patient included sex, age, occupation, burn location, burn cause, and the hazard category of the chemical which caused the burn. Data regarding wound site and size, accompanying injuries, serum electrolyte levels, operations, length of hospital stay, and mortality were also assessed. RESULTS: A total of 201 patients (189 males, 12 females; average age: 38.33 ± 10.57 years) were admitted due to HF burns. Over the 10-year period, the morbidity of HF burns in the past 10 years showed a gradual increase, which paralleled the development of local fluoride industries. Most HF injuries were work related and distributed in working-age patients. Aqueous HF solutions, especially highly concentrated ones, were the most common chemical cause of HF burns. Moreover, inappropriate operation, machine problems, and inadequate protection were identified as the leading causes of HF burns in the workplace. The burn area was <5% of TBSA in more than 90% of patients, and the most common burn sites were the head, neck, and upper extremities. Approximately 17% of patients underwent surgical operation. Accompanying injuries should be detected and treated correctly in a timely manner. Lastly, electrolyte imbalances, such as hypocalcaemia, hypomagnesaemia, and hypokalaemia, occurred frequently in patients with HF exposure; however, hyperkalaemia was not encountered in this study. CONCLUSION: Based on the epidemiological results for HF burns in this region, the related enterprises and local authorities should be encouraged to upgrade management policies and to provide necessary occupational hazard education and safety training for high-risk occupations within high-risk working populations. Furthermore, the enhancement of hazardous chemicals management is also needed. Finally, for patients with HF exposure, early and correct pre-hospital triage, treatment and consequent in-hospital treatment and procedures should also be improved.

Ten-year epidemiology of chemical burns in western Zhejiang Province, China.

BACKGROUND: Chemical burns occur frequently in western Zhejiang Province. This study documents the epidemiology of chemical burns in the region using burn data from a local specialized hospital. Results from this analysis will assist in the planning of prevention strategies for high-risk occupations and groups. METHODS: A 10-year retrospective analysis was conducted for all patients with chemical burns admitted to the Department of Burn and Plastic Surgery from January 2004 to December 2013. Information obtained for each patient included demographics (gender, age, occupation and education), location of the burn, cause of the burn, and categories of chemicals. Data regarding the season of admittance, prehospital treatment, wound site/size (area, region, and depth), accompanying injuries, operations, length of hospital stay and mortality were also assessed. RESULTS: A total of 690 patients (619 males, 71 females; average age: 30.6±12.4 years) were admitted to the department for chemical burns. Over the 10-year period, the incidence of chemical burns showed an increasing tendency. Chemical burns occurred most frequently in patients aged 20-59 years (94.79%). Most of the chemical burns were work-related, primarily in private enterprises (47.97%) and state-owned enterprises (24.93%). Operations (68.99%) and machine problems (17.26%) were the main causes of chemical burns in the workplace. With regard to burns caused by chemicals, most were caused by acids (72.01%), with hydrofluoric acid and sulphuric acid causing 51.45%. Most chemical burns occurred in the summer and autumn seasons (61.02%). The burn size was <10% of the total body surface area (TBSA) for 445 patients (64.49%), while only 26 patients (3.76%) had burns covering >40% TBSA. The most common burn sites were the upper extremities (31.57%), lower extremities (19.86%), and head and neck (28.83%). Most patients (581 (84.20%)) received water washing treatment on site immediately after exposure. The most common accompanying injuries included inhalation injury, ocular burns and digestive tract injury. The average hospital stay was 17.0±23.1 days (range 1-333 days). Surgery was performed in 146 patients (21.16%), and the overall mortality rate was 0.58%. CONCLUSIONS: Chemical burns are preventable. The high morbidity of chemical burns in western Zhejiang Province is related to the industrial structure of the area. Governmental management in the fields of production, transportation, and utilization of chemicals could be improved. Workplaces have the responsibility to provide safe work environments and equipment, as well as occupational education and safety training for high-risk work groups.