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• Autologous skin cell suspensions can be used in combination with negative pressure wound therapy. • There are no negative aspects to this technique when comparing to controls. • This technique improves graft adherence and elasticity of healed wounds. Negative pressure wound therapy (NPWT) is an option for securing meshed split thickness skin grafts (mSTSGs) after burn excision to optimize skin graft adherence. Recently, the use of autologous skin cell suspension (ASCS) has been approved for use in the treatment of burn injuries in conjunction with mSTSGs.To date, limited data exists regarding the impact of NPWT on healing outcomes when the cellular suspension is utilized. It was hypothesized that NPWT would not negatively impact wound healing of ASCS+mSTSG. A burn, excision, mSTSG, ASCS ± NPWT model was used. Two Duroc pigs were utilized in this experiment, each with 2 sets of paired burns. Four wounds received mSTSG+ASCS+NPWT through post-operative day 3, and 4 wounds received mSTSG+ACSC+ traditional ASCS dressings. Cellular viability was characterized prior to spraying. Percent re-epithelialization, graft-adherence, pigmentation, elasticity, and blood perfusion and blood vessel density were assessed at multiple time points through 2 weeks. All wounds healed within 14 days with minimal scar pathology and no significant differences in percent re-epithelialization between NPWT, and non-NPWT wounds were observed. Additionally, no differences were detected for pigmentation, perfusion, or blood vessel density. NPWT treated wounds had less graft loss and improved elasticity, with elasticity being statistically different. These data suggest the positive attributes of the cellular suspension delivered are retained following the application of negative pressure. Re-epithelialization, revascularization, and repigmentation are not adversely impacted. The use of NPWT may be considered as an option when using ASCS with mSTSGs for the treatment of full-thickness burns. [ABSTRACT FROM AUTHOR]

Bioassays measuring the induction of vitellogenin gene expression in male fish are widely used for revealing estrogenic activity in water samples. Measuring induction of vitellogenin mRNA in males by means of RT-PCR analysis is a sensitive way to detect exposure to estrogenic chemicals. To date, little work has been done to examine variations in exposure conditions for assessing estrogenic activity in water samples using this model system. Here we report the results of experiments investigating the effects of volume of treatment water, time since removal from treatment water (depuration), and short-term food deprivation on vitellogenin mRNA induction in male Japanese medaka (Oryzias latipes). Fish exposed to a single concentration of E2 while volume was manipulated were found to have similar levels of vitellogenin mRNA, though more E2 was present at larger volumes. Removal of fish from E2-treated-water to clean water after exposures reduced vitellogenin levels in as little 24h, however, the vitellogenin levels of the fish transferred to the clean water remained above those of the control fish for at least 72h. Depriving fish of food for up to 72h during exposure to E2 did not significantly reduce vitellogenin induction. Together these results support the conclusion that real time RT-PCR measurement of vitellogenin in male fish can be used as a robust indicator of exposure to estrogenic contaminants in water. [Copyright &y& Elsevier]

Literature examining the connection between obesity and burn injuries is limited. This study is a secondary analysis of a multicenter trial data set to investigate the association between burn outcomes and obesity following severe burn injury. Body mass index (BMI) was used to stratify patients as normal weight (NW; BMI 18.5-25), all obese (AO; any BMI>30), obese I (OI; BMI 30-34.9), obese II (OII; BMI 35-39.9), or obese III (OIII; BMI>40). The primary outcome examined was mortality. Secondary outcomes included hospital length of stay (LOS), number of transfusions, injury scores, infection occurrences, number of operations, ventilator days, intensive care unit LOS, and days to wound healing. Of 335 patients included for study, 130 were obese. Median total body surface area (TBSA) was 31%, 77 patients (23%) had inhalation injury and 41 patients died. Inhalation injury was higher in OIII than NW (42.1% versus 20%, P = 0.03). Blood stream infections (BSI) were higher in OI versus NW (0.72 versus 0.33, P = 0.03). Total operations, ventilator days, days to wound healing, multiorgan dysfunction score, Acute Physiology and Chronic Health Evaluationscore, hospital LOS, and intensive care unit LOS were not significantly affected by BMI classification. Mortality was not significantly different between obesity groups. Kaplan–Meier survival curves did not significantly differ between the groups (χ2 = 0.025, P = 0.87). Multiple logistic regression identified age, TBSA, and full thickness burn as significant independent predictors (P < 0.05) of mortality; however, BMI classification itself was not predictive of mortality. No significant association between obesity and mortality was seen after burn injury. Age, TBSA, and percent full- thickness burn were independent predictors of mortality after burn injury, while BMI classification was not. [ABSTRACT FROM AUTHOR]

Abstract: Background: There is a discrepancy between publically available data from the United Network for Organ Sharing (UNOS) database and perception of the incidence of mortally burn-injured patients serving as organ donors. In the last 5 y, a single burn center referred several patients who went on to successfully donate multiple organs. However, UNOS data indicate very few referrals of patients with burn injuries nationwide. This discrepancy in UNOS-reported occurrences versus institutional experience prompted this work. Methods: UNOS data from 1988–2012 was examined for causes of death related to thermal injury, electrical injury, inhalation injury, or carbon monoxide poisoning. The National Burn Repository was examined for burn center death rates and patient characteristics of those with reported nonsurvivable burn injuries. Finally, a national survey queried the clinical experiences and educated opinions of burn center directors, transplant surgeons, and organ procurement organization (OPO) representatives regarding organ donation in the burn-injured population. Results: Between 42% and 52% of those surveyed responded. Survey data indicate that at least 61 patients with burn-related injuries have served as organ donors in the past 5 y alone, versus 23 identified in 24 y of UNOS data. Survey data also indicate that inhalation injuries were the most common burn-related injuries seen before successful organ procurement. Kidneys were the most commonly donated organs, but all major organs and tissues were represented in the experiences of surgeon and organ procurement organization respondents. Up to 10% surgeon respondents believe that patients with burn injuries should not be referred for possible organ donation. Conclusions: There are more organs donated by patients with mortal burn injuries than currently available UNOS data would suggest. Survey data suggest that these patients should be able to contribute successfully to the supply of organs needed by those on transplant waiting lists, but remain inconsistently recognized as such a resource. Knowledge about long-term organ and tissue viability from burn-injured patients is lacking, and should be the focus of future research. [Copyright &y& Elsevier]

Burn progression is a phenomenon that remains poorly characterized. The mechanisms of burn conversion are not completely understood, and consequently, both predictive diagnostic tools and interventions are limited. The rat comb burn model is a commonly used approach to study horizontal burn conversion. However, there is significant variability in how the model is performed. Skin contact duration, comb device heating method, comb heating duration, amount of pressure applied, the weight of the comb, and associated depth of burn are all variables that are heterogeneous in studies utilizing the model. Here, contact duration was examined to determine the impact the duration of burn delivery has on the conversion of interspaces in this model. Data from multiple experiments consisting of 10, 15, 20, 30, 40, and 45 s comb burns were compiled and assessed. Burns were made using combs heated in a 100°C dry bath and then monitored for 2 d. Interspace viability was assessed by digital and laser doppler imaging and biopsy procurement. Laser Doppler Imaging and viable interspace measurements showed that as burn duration increased, the percentage of the viable interspace and interspace perfusion decreased. Additionally, a contact time of 30 s or greater was required to result in 100% interspace conversion. These results demonstrate a need to better characterize and potentially standardize the rat comb burn model to reduce variation and maintain it as a valuable tool for controlled studies of the pathophysiology of burn wound progression. • There is considerable variability in model variables used in the comb burn model that affect outcomes and clinical translatability. • In combs heated in a dry bath, a 30 s contact time leads to 100% interspace conversion. • In testing treatments for burn conversion using this model, investigators should take care to report model variables as stated in this manuscript. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) can damage macromolecules if not appropriately neutralized by ROS scavengers. The balance between ROS and ROS scavengers is essential to prevent the accumulation of damage in healthy tissues. This balance is perturbed in hypertrophic scar (HTS). Full-thickness wounds were created on the flanks of Duroc pigs at day 0 that developed into HTS (n = 4). Wounds and HTSs were biopsied weekly for 135 d. Total transcriptome microarrays were conducted with focused ROS scavenger analysis. Confirmatory quantitative reverse transcription polymerase chain reaction and immunofluorescence of ROS scavengers: superoxide dismutase 1, microsomal glutathione S-transferase 1, and peroxiredoxin 6 were performed throughout wound healing and HTS development. Total transcriptome microarray analysis identified over 25 ROS scavenger genes that were significantly downregulated in HTS at all time points compared with basal level controls (BL) (FDR<0.01; fold change > or <2). Ingenuity pathway analysis identified multiple ROS scavenging pathways involved in HTS (P < 0.01). Quantitative reverse transcription polymerase chain reaction of representative scavengers confirmed and expanded this finding to the initial phases of wound healing (P < 0.05, n = 4). The protein products of the genes were lower in wound and HTS tissues compared with BL. A balance between ROS production and scavenging must be maintained for normal wound healing, which is perturbed in wounds that heal to form HTSs. We postulate that endogenous scavengers can be administered as a prophylactic or post-treatment to rebalance ROS and attenuate symptoms of scar. [ABSTRACT FROM AUTHOR]

Abstract Background A complex inflammatory response mediates the systemic effects of burn shock. Disruption of the endothelial glycocalyx causes shedding of structural glycoproteins, primarily syndecan-1 (SDC-1), leading to endothelial dysfunction. These effects may be mitigated by resuscitative interventions. Materials and methods Sprague–Dawley rats were used to create small, medium, and large burns and uninjured controls. Three different intravenous resuscitation protocols were applied within each group: Lactated Ringer's (LR) alone, LR plus fresh frozen plasma (FFP), or LR plus albumin. Blood was serially collected, and plasma SDC-1 was quantified with enzyme-linked immunosorbent assay. In one cohort, Evan's Blue Dye (EBD) was administered and quantified in lung by spectrophotometry as a functional assay of vascular permeability. In a second cohort, intact SCD-1 was quantified by immunohistochemistry in lung tissue. Statistical analysis employed two-way analysis of variance with multiple comparisons and Student's t -test. Results EBD extraction from lung was significantly greater with higher injury severity versus controls. Extraction decreased significantly in large-burn animals with addition of FFP to LR versus LR-only; addition of albumin to LR did not decrease EBD extraction. Plasma SCD-1 increased in injured animals compared with controls, and changes correlated with injury severity in all resuscitation groups (significance, P < 0.05). Lung SCD-1 staining reflected the results in the EBD assay. Conclusions Addition of FFP, not of albumin, to post-burn resuscitation diminishes vascular leakage associated with large burns. Addition of colloid does not affect SDC-1 shedding as measured in plasma. Ongoing work will further define pathophysiologic mechanisms and potential therapeutic interventions to mitigate injury and promote repair of the endothelial glycocalyx. [ABSTRACT FROM AUTHOR]

Background There exists neither a consensus definition of burn “graft loss” nor a scale with which to grade severity. We introduced an institutional scale in 2014 for quality improvement. Materials and methods We reviewed all burned patients with graft loss on departmental Morbidity and Mortality reports between July 2014 and July 2016. Graft loss grades were assigned during the course of clinical care per institutional scale. Chronic nonhealing wounds and nonburn wounds were excluded. Data abstracted included demographics, medical history, injury details, surgical procedures, graft loss, and lengths of stay (LOS). Photos of affected areas were graded by two blinded surgeons, and a linear weighted κ was calculated to assess interrater agreement. Results Graft loss was noted in 50 patients, with 43 remaining after exclusions. Mean age was 50.1 y. The majority were male (58.1%) and African American (41.9%). Smoking (30.2%) and diabetes (27.9%) were prevalent. Total body surface area involvement ranged from 0.5% to 51.0% (11.8 ± 12.3%). Grade I graft loss was documented on one patient (2.3%), Grade II in 15 (34.9%), Grade III in 12 (27.9%), and Grade IV in 15 (34.9%). Reoperation was performed in 20 (46.5%). Hospital LOS was longer than predicted in 38 patients (88.4%). Seven had significant morbidity, including two amputations. Moderate agreement was reached between blinded surgeons (κ = 0.44, P = 0.004). Conclusions Graft loss is a major source of morbidity in burn patients. In this cohort, reoperation was common and hospital LOS was extended. Use of a grading scale improves dialog among providers and enables improved understanding of risk factors. [ABSTRACT FROM AUTHOR]

Background Studies associating coagulopathic changes with burn injury have relied on limited tests such as partial thromboplastin time (PTT) and international normalized ratio (INR). Understanding the clotting dynamics and associated risk factors after burn injury could influence management. This work aimed to identify real-time changes in coagulation after burn injury not indicated by PTT or INR alone. Materials and methods Nine burn-injured patients at a regional burn center were enrolled for blood collection at admission and set intervals over 96 h. Patient demographics, management, and laboratory data (PTT and INR) were collected. Plasma assays determined factors II, V, VII, VIII, IX, X, XI, antithrombin, and protein C functional activity as well as PAP, D-Dimer, fibrin monomer, TFPI, IL-1b, IL-6, IL-10, IL-12p.70, and TNF-α concentrations. Results Overall, five patients died. These patients had higher mortality scores and were more acidotic. All patients had normal coagulation studies (INR < 1.5, PTT < 45 s) within 24 h of admission, and only two were abnormal after. Increased factor VIII and IX activity were identified in seven patients at admission. Decreased antithrombin and protein C activity were seen in all patients. Patients had increased PAP, D-Dimer, and fibrin monomer concentrations throughout their hospital course. At admission, increased fold changes were seen in IL-6 (2.5–117) and IL-10 (2.4–32), whereas IL-1b and TNF-α levels were depressed in all patients. Conclusions Extensive changes not identified by PTT or INR were seen after burn injury that may explain perturbed coagulation in these patients. This approach further characterizes the impact thermal injury has on coagulation. [ABSTRACT FROM AUTHOR]

Background The effects of pressure on hypertrophic scar are poorly understood. Decreased extracellular matrix deposition is hypothesized to contribute to changes observed after pressure therapy. To examine this further, collagen composition was analyzed in a model of pressure therapy in hypertrophic scar. Materials and methods Hypertrophic scars created on red Duroc swine ( n = 8) received pressure treatment (pressure device mounting and delivery at 30 mm Hg), sham treatment (device mounting and no delivery), or no treatment for 2 wk. Scars were assessed weekly and biopsied for histology, hydroxyproline quantification, and gene expression analysis. Transcription levels of collagen precursors COL1A2 and COL3A1 were quantified using reverse transcription-polymerase chain reaction. Masson trichrome was used for general collagen quantification, whereas immunofluorescence was used for collagen types I and III specific quantification. Results Total collagen quantification using hydroxyproline assay showed a 51.9% decrease after pressure initiation. Masson trichrome staining showed less collagen after 1 ( P < 0.03) and 2 wk ( P < 0.002) of pressure application compared with sham and untreated scars. Collagen 1A2 and 3A1 transcript decreased by 41.9- and 42.3-fold, respectively, compared with uninjured skin after pressure treatment, whereas a 2.3- and 1.3-fold increase was seen in untreated scars. This decrease was seen in immunofluorescence staining for collagen types I ( P < 0.001) and III ( P < 0.04) compared with pretreated levels. Pressure-treated scars also had lower levels of collagen I and III after pressure treatment ( P < 0.05) compared with sham and untreated scars. Conclusions These results demonstrate the modulation of collagen after pressure therapy and further characterize its role in scar formation and therapy. [ABSTRACT FROM AUTHOR]