Recent Advances in Experimental Burn Models

Experimental burn models are essential tools for simulating human burn injuries and exploring the consequences of burns or new treatment strategies. Unlike clinical studies, experimental models allow a direct comparison of different aspects of burns under controlled conditions and thereby provide relevant information on the molecular mechanisms of tissue damage and wound healing, as well as potential therapeutic targets. While most comparative burn studies are performed in animal models, a few human or humanized models have been successfully employed to study local events at the injury site. However, the consensus between animal and human studies regarding the cellular and molecular nature of systemic inflammatory response syndrome (SIRS), scarring, and neovascularization is limited. The many interspecies differences prohibit the outcomes of animal model studies from being fully translated into the human system. Thus, the development of more targeted, individualized treatments for burn injuries remains a major challenge in this field. This review focuses on the latest progress in experimental burn models achieved since 2016, and summarizes the outcomes regarding potential methodological improvements, assessments of molecular responses to injury, and therapeutic advances

Experimental Study of Burn Damage Progression in a Human Composite Tissue Model

Comparative studies of human tissue damage caused by burns are challenging because precise information regarding the temperature, time, and duration of the exposure is often missing. Animal models cannot be fully translated to the human system due to interspecies differences in cutaneous tissues. We used a human composite tissue model to compare tissue damage caused by thermal burns with different dynamics. Equal subcutaneous/cutaneous composite tissue samples from six donors were first exposed to either preheated steel (100 °C) or a precision flame burner (300 °C) and were then maintained in vitro for seven days. Histological and immunohistochemical analyses revealed that flame burns instantly caused deep and stable damage to the subcutaneous tissue, which stayed constant for seven days. By contrast, contact burns inflicted tissue damage that was initially superficial but then expanded deeper into the adipose tissue. This spatiotemporal expansion of tissue damage was essentially accompanied by macrophage and fibroblast activation, which points towards inflammation resolution and wound healing. Our study suggests that thermal differences in burns directly influence the course of tissue damage, the cellular response and, consequently, the likely dynamics of repair processes days after burn injuries

Experimental Study of Burn Damage Progression in a Human Composite Tissue Model

Comparative studies of human tissue damage caused by burns are challenging because precise information regarding the temperature, time, and duration of the exposure is often missing. Animal models cannot be fully translated to the human system due to interspecies differences in cutaneous tissues. We used a human composite tissue model to compare tissue damage caused by thermal burns with different dynamics. Equal subcutaneous/cutaneous composite tissue samples from six donors were first exposed to either preheated steel (100 °C) or a precision flame burner (300 °C) and were then maintained in vitro for seven days. Histological and immunohistochemical analyses revealed that flame burns instantly caused deep and stable damage to the subcutaneous tissue, which stayed constant for seven days. By contrast, contact burns inflicted tissue damage that was initially superficial but then expanded deeper into the adipose tissue. This spatiotemporal expansion of tissue damage was essentially accompanied by macrophage and fibroblast activation, which points towards inflammation resolution and wound healing. Our study suggests that thermal differences in burns directly influence the course of tissue damage, the cellular response and, consequently, the likely dynamics of repair processes days after burn injuries

RNA mapping : methods and protocols / edited by M. Lucrecia Alvarez, Mahtab Nourbakhsh.

pharmacy bookfair2015Includes bibliographical references and index.xi, 375 pages

Determining the status of activity of daily living (ADL) and instrumental activity of daily living (IADL) in healthy and cognitive impaired elderlies

Background & Objective: Dementia is associated with serious effects on memory, cognition and ability to carry out daily activities. There is evidence that impairment in activity of daily living (ADL) is even reported among elder patients who suffer from mild cognitive disorders. Therefore, we aimed to determine the status of ADL and instrumental activity of daily living (IADL) in healthy and cognitive impaired elderlies (MCI, Mild, and Moderate dementia). Methods: In this cross-sectional study which was conducted in 2016, 300 elderlies (60 years and above) were selected using a classified cluster sampling in four groups (each group of 75 individuals). These groups comprised of healthy old people and elderlies with mild cognitive impairment (MCI) and mild to moderate dementia that were residing in rural areas of Isfahan and Tehran and were classified between stages of 1 to 5 according to the Global Deterioration Scale (GDS). All individuals in four groups were assessed by ADL and IADL evaluation tools. The geriatric depression scale (GDS-15) and DSM-IV scale were performed on healthy elderlies by a physician to confirm the lack of mild dementia or depression. Data were analyzed by SPSS 20 software and using descriptive statistics, analysis of variance and independent samples T-test. Results: According to the cognitive impairment screening results by GDS, 76 elderlies were healthy, 75 were in MCI group, 72 individuals were diagnosed with mild dementia and 77 were suffering from moderate dementia. The mean scores of ADL tool on the basis of different cognitive stages of elderlies were statistically significant (p<0.001). The ADL scores among elderlies were lowered by increasing the severity of cognitive impairment. Moreover, the average scores of IADL among elderlies with different cognitive status were significantly different (p<0.001). The IADL scores in cases with moderate dementia were markedly declined in comparison to healthy subjects and elderlies with MCI and mild dementia. Conclusion: Although applying the ADL and IADL tools are not considered as gold standards in rapid assessment of cognitive impairments among elderlies, they could be considered as useful and user friendly tools to detect performance alterations in elderlies with dementia to provide healthcare by geriatric teams

Farnesol-Loaded Nanoliposomes Inhibit Inflammatory Gene Expression in Primary Human Skeletal Myoblasts

There is a substantial unmet need for the treatment of skeletal muscle mass loss that is associated with aging and obesity-related increases in FFA. Unsaturated FFAs stimulate the inflammatory gene expression in human skeletal myoblasts (SkMs). Farnesol is a hydrophobic acyclic sesquiterpene alcohol with potential anti-inflammatory effects. Here, we created farnesol-loaded small unilamellar (SUVs) or multilamellar lipid-based vesicles (MLVs), and investigated their effects on inflammatory gene expression in primary human skeletal myoblasts. The attachment of SUVs or MLVs to SkMs was tracked using BODIPY, a fluorescent lipid dye. The data showed that farnesol-loaded SUVs reduced FFA-induced IL6 and LIF expression by 77% and 70% in SkMs, respectively. Farnesol-loaded MLVs were less potent in inhibiting FFA-induced IL6 and LIF expression. In all experiments, equal concentrations of free farnesol did not exert significant effects on SkMs. This report suggests that farnesol, if efficiently directed into myoblasts through liposomes, may curb FFA-induced inflammation in human skeletal muscle