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M C Crossland

Publications and source records attributed to M C Crossland.

5 recordsLinked to original sources
PubMed1998

Interleukin-1alpha and collagenase activity are elevated in chronic wounds.

Interleukin-1-alpha (IL-1alpha) is a member of a family of proinflammatory polypeptide mediators that has been shown in vitro to stimulate collagenase production. Collagenase is a proteolytic enzyme classified as one of the matrix metalloproteinases (MMP-1) that specifically recognizes and cleaves collagen. Therefore, the objective of this study was to compare the levels of these two proteins in chronic wounds as possible factors in the pathogenesis of chronic wounds. Fluids from 10 chronic wounds were collected before and after a 1-week treatment with a hydroactive dressing (Cutinova cavity). In addition, fluids were collected from 20 acute wounds for comparison. IL-1alpha and MMP-1 levels were quantified using sandwich ELISA. Collagenase activity was measured using a radiolabeled collagen as substrate. Clinically, the chronic wounds showed decreased area (-21.0 cm2) and reduced volume (-134.5 cm3) by 4 weeks after treatment with the hydroactive dressing. There were no significant differences in the protein concentrations between acute wound fluids (21.0 +/- 3.0 mg/ml) and chronic wound fluids before and after treatment with the hydroactive dressing (18.3 +/- 5.5 and 25.2 +/- 7.6 mg/ml, respectively). Levels of IL-1alpha in the acute wound fluids were low (0.019 pg/mg), whereas in the chronic wound fluid before treatment they had been significantly elevated (44.9 + 21.8 pg/mg). Following treatment with the hydroactive dressing, the IL-1alpha levels dropped to 10.3 + 3.3 pg/mg (p < 0.05). Collagenase activity was not detectable in acute wound fluid, elevated in pretreatment chronic wounds (12.9 + 3.4 units), and decreased in chronic wounds after treatment (11.4 + 3.3 units). This study correlated clinical healing of chronic wounds with biochemical changes in the ulcer microenvironment. As the chronic wounds began to heal, there was a significant decrease in the IL-1alpha levels and collagenase activity, thus suggesting that these two proteins may contribute to the lack of healing characteristic of chronic wounds.

Chronic Disease↗
PubMed1997

Wound healing management: enhancing patient outcomes and reducing costs.

Biomedical technology as applied to wound healing management allows specific evaluations of the oxygen-related pathophysiology of non-healing wounds. In many of these cases the use of transcutaneous oxygen mapping of the skin and hyperbaric oxygen (HBO) therapy as an adjunctive treatment for non-healing wounds speeds the healing process. While HBO treatment has remained a covered service for hospital-based care, only recently have treatment algorithms for its application in an outpatient setting been available. This technological advancement has also been a factor in the development of cost effective wound healing centers (WHC) in community hospitals. Better outcomes for many chronic wounds are achieved by combining a multidisciplinary team approach using advanced technologies. In this article the case of a soft-tissue radiation necrosis ulceration of the leg successfully treated with adjunctive HBO is presented. In this example, a reduction in patient charges of greater than 30% was achieved as compared to costs associated with traditional surgical/hospital management of the condition.

Cost Savings↗
PubMed1995

Topical application of epidermal growth factor onto partial-thickness wounds in human volunteers does not enhance reepithelialization.

Recent reports have suggested that human epidermal growth factor will accelerate the healing of corneal wounds and donor sites of burned patients undergoing split-thickness skin grafts. In one report using human epidermal growth factor in a silver sulfadiazine cream, these data were gathered from patients of various ages who had various depths of donor sites and degrees of burn. Therefore, despite the fact that these data were prospective, randomized, and double-blinded, we questioned the validity of the study. To test the hypothesis that topical application of human epidermal growth factor will enhance the healing of partial-thickness wounds, we utilized healthy volunteers (n = 17) and created bilateral split-thickness skin wounds (4 cm2) of the same depth (0.014 in) on each flank and then studied time until total epithelialization occurred. One side was treated with silver sulfadiazine as a control and the opposite side with silver sulfadiazine and human epidermal growth factor. There was no significant difference in the healing times between the human epidermal growth factor-treated sites and the silver sulfadiazine cream controls.

Administration, Topical↗
PubMedDate not supplied

Comparison of the polyvinyl alcohol sponge and expanded polytetrafluoroethylene subcutaneous implants as models to evaluate wound healing potential in human beings.

Our current understanding of the complex processes involved in wound healing is based mainly on studies of animal models. Although this information has been useful, it may not totally reflect the response found in human beings. For example, human beings have a tendency to either "overheal," as seen in keloids and hypertrophic scar formation, or have deficient healing, as seen in chronic ulcer formation. No animal models are available to analyze these human clinical pathologic conditions. Therefore the objective of this study was to analyze the wound healing response in a large population (n = 40) of normal healthy human beings as a first step to begin studies of abnormal human wound healing. Simultaneously, a comparison was made between the polyvinyl alcohol implant and the expanded polytetrafluoroethylene implant model. Under sterile conditions with the use of local anesthesia, two preweighed polyvinyl alcohol implants and two standard 6 cm expanded polytetrafluoroethylene implants were placed subcutaneously in the upper arm of each subject. High-performance liquid chromatography was used to quantitate isoleucine and hydroxy-l-proline in acid hydrolysates of each implant. Isoleucine was used as an indicator of protein content in the tissue sample, whereas hydroxyproline reflected collagen content. No infectious or hemorrhagic complications were found in the 40 volunteers included in the study. No significant difference was found in isoleucine or hydroxy-l-proline content between postoperative day 7 polyvinyl alcohol implants and day 14 polyvinyl alcohol implants. In contrast, both isoleucine and hydroxy-l-proline content were significantly increased in day 14 expanded polytetrafluoroethylene implants compared with day 7 implants (p < 0.005 and p < 0.001, respectively). In addition, the ratio of hydroxy-l-proline to isoleucine was significantly increased in day 14 expanded polytetrafluoroethylene implants compared with day 7 expanded polytetrafluoroethylene and both day 7 and day 14 polyvinyl alcohol implants (p < 0.001). This observation suggests that by 14 days implantation of expanded polytetrafluoroethylene stimulated an increased deposition of collagen. No significant differences were found in the hydroxy-l-proline to isoleucine ratios among day 7 expanded polytetrafluoroethylene, day 7 polyvinyl alcohol, and day 14 polyvinyl alcohol implants. Histologic analyses correlated with the biochemical findings. These results suggest that expanded polytetrafluoroethylene may be the preferred implant for studies designed to examine pathologic processes associated with retarded wound healing. In contrast, the polyvinyl alcohol implant may be better suited for studies where a low background response is required. Moreover, the extreme variability in normal healthy volunteers seen in this study correlates clinically with the finding that, among the normal adult human population, there is a heterogeneous wound healing response.

Journal Article↗