severe-burn-injury-in-a-swine-model-for-clinical-dressing-assessment

Severe Burn Injury in a Swine Model for Clinical Dressing Assessment

Wound healing is a dynamic repair process and is the most complex biological process in human life. In response to burn injury, alterations in biological ...

wet-spinning-based-molding-process-of-gelatin-for-tissue-regeneration

Wet-spinning-based Molding Process of Gelatin for Tissue Regeneration

This article presents an inexpensive method to fabricate gelatin, as a natural polymer, into monofilament fibers or other appropriate forms. Through the ...

Hypertrophic scarring is related to persistent activation of transforming growth factor-β (TGF-β)/Smad signaling. In the TGF-β/Smad signaling cascade, the TGF-β type I receptor (TGFBRI) phosphorylates Smad proteins to induce fibroblast proliferation and extracellular matrix deposition. In this study, we inhibited TGFBRI gene expression via TGFBRI small interfering RNA (siRNA) to reduce fibroblast proliferation and extracellular matrix deposition. Our results demonstrate that downregulating TGFBRI expression in cultured human hypertrophic scar fibroblasts significantly suppressed cell proliferation and reduced type I collagen, type III collagen, fibronectin, and connective tissue growth factor (CTGF) mRNA, and type I collagen and fibronectin protein expression. In addition, we applied TGFBRI siRNA to wound granulation tissue in a rabbit model of hypertrophic scarring. Downregulating TGFBRI expression reduced wound scarring, the extracellular matrix deposition of scar tissue, and decreased CTGF and α-smooth muscle actin mRNA expression in vivo. These results suggest that TGFBRI siRNA could be applied clinically to prevent hypertrophic scarring. 

siRNA-targeting transforming growth factor-β type I receptor reduces wound scarring and extracellular matrix deposition of scar tissue.

Objective. Postinfarction transneuronal degeneration refers to secondary neuronal death that occurs within a few days to weeks following the disruption of input or output to synapsed neurons sustaining ischemic insults. The thalamus receives its blood supply from the posterior circulation; however, infarctions of the middle cerebral arterial may cause secondary transneuronal degeneration in the thalamus. In this study, we presented the areas of ischemia and associated transneuronal degeneration following MCAo in a rat model. Materials and Methods. Eighteen 12-week-old male Sprague-Dawley rats were randomly assigned to receive middle cerebral artery occlusion surgery for 1, 7, and 14 days. Cerebral atrophy was assessed by 2,3,5-triphenyltetrazolium hydrochloride staining. Postural reflex and open field tests were performed prior to animal sacrifice to assess the effects of occlusion on behavior. Results. Myelin loss was observed at the lesion site following ischemia. Gliosis was also observed in thalamic regions 14 days following occlusion. Differential degrees of increased vascular endothelial growth factor expression were observed at each stage of infarction. Increases in myelin basic protein levels were also observed in the 14-day group. Conclusion. The present rat model of ischemia provides evidence of transneuronal degeneration within the first 14 days of occlusion. The observed changes in protein expression may be associated with self-repair mechanisms in the damaged brain. 

Transneuronal Degeneration of Thalamic Nuclei following Middle Cerebral Artery Occlusion in Rats.

Alginate is a natural rich anionic polysaccharide (APS), commonly available as calcium alginate (CAPS). It can maintain a physiologically moist microenvironment, which minimises bacterial infection and facilitates wound healing at a wound site. Patients with burn injuries suffer from pain and an inflammatory response. In this study, we evaluated the CAPS dressing and traditional dressing containing carboxymethyl cellulose (CMC) for wound healing and scar tissue formation in a burn model of rat and swine. In our pilot study of a burn rat model to evaluate inflammatory response and wound healing, we found that the monocyte chemoattractant protein (MCP)-1 and transforming growth factor (TGF)-β were up-regulated in the CAPS treatment group. Next, the burn swine models tested positive for MCP-1 in a Gram-positive bacterial infection, and there was overproduction of TGF-β during the burn wound healing process. Rats were monitored daily for 1 week for cytokine assay and sacrificed on day 28 post-burn injury. The swine were monitored over 6 weeks. We further examined the pain and related factors and inflammatory cytokine expression in a rodent burns model monitored everyday for 7 days post-burn. Our results revealed that the efficacy of the dressing containing CAPS for wound repair post-burn was better than the CMC dressing with respect to natural wound healing and scar formation. The polysaccharide-enriched dressing exerted an antimicrobial effect on burn wounds, regulated the inflammatory response and stimulated anti-inflammatory cytokine release. However, one pain assessment method showed no significant difference in the reduction in levels of adenosine triphosphate in serum of rats after wound dressing in either the CAPS or CMC group. In conclusion, a polysaccharide-enriched dressing outperformed a traditional dressing in reducing wound size, minimising hypertrophic scar formation, regulating cytokines and maximising antimicrobial effects.

Enhanced wound-healing performance of a phyto-polysaccharide-enriched dressing - a preclinical small and large animal study.

The pathogenesis of ketamine cystitis (KC) has been recently linked with immune response to patients but the same has not yet been established. Hence, this study aims to propose a possible immune mechanism of irreversible bladder damage caused by KC. A total of 53 KC patients and 21 healthy volunteers as controls have been retrospectively assessed. The levels of serum immunoglobulin E (IgE), IL-6, and IFN- of KC patients were significantly higher than those of controls, whereas the TGF- levels of KC patients substantially reduced but the IL-2 and IL-4 levels of KC patients were comparable to those of controls. Moreover, the KC patients had significantly higher counts of T1, T2, and T17 cells than those of controls. The immune response of KC users may begin with the IL-6 production and differentiation of T17 and may be followed by alternating between high expressions of T1 and T2. The IL-6 may further suppress the T cells which can aggravate chronic inflammation in KC patients and the imbalance in T17 and T cells may involve the pathogenesis of KC. Further investigation is needed to define the role of IL-6 in T1/T2/T17-regulated signaling pathway in ketamine-induced cystitis.

The Immunomodulatory Imbalance in Patients with Ketamine Cystitis.

Repair and regeneration of craniofacial tissues is particularly challenging because they comprise a complex structure of hard and soft tissues involved in intricate functions. This study combined collagen scaffolds and human adipose stem cells (hASCs) for oral mucosal and calvarial bone regeneration by using resveratrol (RSV), which affects the differentiation of mesenchymal stem cells. We have evaluated the effect of collagen scaffold-containing RSV (collagen/RSV) scaffolds both in vitro and in vivo for their wound healing and bone regeneration potential. Scanning electron microscopy and immunostaining results reveal that hASCs adhere well to and proliferate on both collagen scaffolds and collagen/RSV scaffolds. Oral mucosal lesion experiments demonstrated that the collagen/RSV scaffold is more effective in wound closure and contraction than the collagen scaffold. The micro-computed tomography (μCT) images of calvarial bone display regenerating bone in defects covered with hASCs on collagen/RSV scaffolds that are more visible than that in defects covered with hASCs on a collagen scaffolds. RSV was more effective at inducing hASC differentiation on the collagen scaffold, suggesting that collagen/RSV scaffolds can provide useful biological cues that stimulate craniofacial tissue formation.

ArticleTotal : 2	Year
Publication title Cited by 5	2018
Publication title Cited by 5	2019

Article	Year
siRNA-targeting transforming growth factor-β type I receptor reduces wound scarring and extracellular matrix deposition of scar tissue. The Journal of investigative dermatology\| PubMed ID: 24670383	2014
Transneuronal Degeneration of Thalamic Nuclei following Middle Cerebral Artery Occlusion in Rats. BioMed research international\| PubMed ID: 27597962	2016
Enhanced wound-healing performance of a phyto-polysaccharide-enriched dressing - a preclinical small and large animal study. International wound journal\| PubMed ID: 28941182	2017
The Immunomodulatory Imbalance in Patients with Ketamine Cystitis. BioMed research international\| PubMed ID: 29204439	2017
Combination of resveratrol-containing collagen with adipose stem cells for craniofacial tissue-engineering applications. International wound journal\| PubMed ID: 29536622	2018

Juin-Hong Cherng

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