bluuebunny/crossref_metadata_2025 huggingface dataset:
051 Superoxide Regulates α‐SMA via p‐38 MAPK
Authors: Wang J.H‐C. , Wang G. Q.
Published: March 2007

This study was to investigate the effect of cyclic mechanical stretching on superoxide and nitric oxide production in human patellar tendon fibroblasts (HPTFs) and to establish the role of superoxide and p38 MAPK in stretching‐induced α‐smooth muscle actin (α‐SMA) expression. When HPTFs were grown in deformable silicone dishes and subjected to 8% cyclic, uniaxial stretching, it was found that HPTFs markedly increased the production of superoxide and nitrite but not nitric oxide. And, cyclic stretching of HPTFs increased phosphorylation of p38 MAPK with increasing stretching magnitude. In addition, stretching duration also influenced the expression of phosphorylated p38 MAPK, where the dependence followed a pattern of cellular response in p38 MAPK activation consistent with previous studies using human mesangial cells and rat 3Y1 fibroblasts. For short stretching durations (∼15 min), the expression of phosphorylated p38 MAPK increased rapidly but decreased for longer stretching durations. Furthermore, in HPTFs treated with superoxide dismutase (SOD), which converts superoxide anions to hydrogen peroxide and an oxygen molecule, levels of stretching‐induced p38 MAPK phosphorylation and α‐SMA expression decreased compared to stretched fibroblasts not treated with SOD. Similarly, cells treated with SB202190, which specifically inhibits p38 MAPK activation, also decreased α‐SMA expression levels. Therefore, these results suggest that superoxide regulates stretching‐induced α‐SMA expression via p38 MAPK activation in HPTFs subjected to cyclic stretching conditions.
054 HBO Mediates Increased Nitric Oxide Production Associated with Wound Healing
Authors: Boykin J.V. , Baylis C. , Sommer V. , Shawler L. , Watkins M. , Young J. , Louissaint S. , Crossland M.
Published: March 2007

Hyperbaric oxygen (HBO) is used adjunctively to treat chronic, non‐healing wounds. Increased nitric oxide (NO) production during HBO is suggested as an important mechanism that promotes enhanced wound healing. The purpose of this study is the documentation of NO production during and following HBO treatments (txs). Diabetic and non‐diabetic patients receiving HBO therapy (20 txs; 2.0ATA × 90 min) provided wound fluid and fasting plasma and urine specimens for nitrate (NOx) determinations. Nitrate measurements were obtained prior to HBO (baseline), after 10 and 20 txs, and at one and four weeks following HBO completion. In patients healing after HBO baseline plasma NOx ranged between 17.7 and 33.20 μM. At 10 txs plasma NOx increased >50% to between 35.8–43.5 μM. At 20 txs plasma NOx decreased to between 22.3–35.5 μM. Healing diabetic patient plasma NOx increased after HBO reaching 170% of baseline at one month (57.8 ± 0.15 μM). Plasma NOx of healing non‐diabetic patients decreased to baseline levels at one month after HBO. Urine NOx values mirrored those of plasma NOx; wound fluid NOx elevations were delayed compared to plasma and urine. Conversely, non‐healing HBO patients did not demonstrate the early, significant elevations of plasma NOx after 10 txs. This study documents, for the first time, an early (10 txs), significant elevation of plasma and urine NOx after HBO that is associated with successful healing in diabetic and non‐diabetic patients. A similar early increase in plasma and urine NOx was not observed in patients not responding to HBO therapy. These findings suggest that HBO‐mediated increased NO production plays a critical role in the correction of impaired wound healing in selected patients. Furthermore, early plasma and urine NOx determinations after HBO therapy may prove valuable in the prediction of the clinical outcome of treatment.
060 The Effect of Localized Intra‐abdominal Infection on Colon Anastomotic Healing in Rats
Authors: Kurt T. , Tatar A. , Vladimir F. , Cassaro S. , Cioroiu M. , Grossi R.
Published: March 2007

Previous studies have demonstrated a decrease in intestinal healing in intra‐abdominal infection. Currently, the effect of localized intra‐abdominal infection on anastomotic healing and strength is not known. This study was designed to evaluate anastomotic wound healing in the presence of intra‐abdominal abscess.

30 male Sprague Dawley rats weighing 270–300 grams were used for this experiment. 20 animals underwent cecal ligation and puncture (CLP) with 16 gauge needle. They were followed for 14 days. 9 of them died in the first week. The CLP animals had an initial 20% weight loss; however by day 10 they had a gradual return toward control weight. At the end of 14 days, rats from CLP group (n = 11) and control group (n = 10) underwent laparotomy and single‐layer left colonic anastomosis. Blood cultures and abdominal swab cultures were sent from both groups. Post‐operatively, animals were allowed to recover, food and water were offered ad libitum. At post‐operative day five, animals were euthanized by thiopental overdose. Following anastomotic bursting pressure measurements, two samples were taken from the anastomotic line for subsequent determination of hydroxyproline content. Groups were compared with Students’t test. Data were expressed as means ± SEM.

In the post‐operative period, all rats lost 10% to 12% of their body weight. No bacterial growth was detected in cultures. Hydroxyproline content measurements were significantly higher in the CLP group (11.2 ± 0.3 vs. 9.8 ± 0.5 ug HPO/mg dry tissue weight. P < 0.05). On the other hand, no significant difference was observed in bursting pressure measurements between the groups (177 ± 6.3 vs. 164 ± 10.4 mmHg. P > 0.05).

These findings suggest that localized intra‐abdominal infection without sepsis doesn’t inhibit intestinal anastomotic healing.

Supported by a grant from Turkish Scientific and Technical Research Council.
064 Proliferation and Growth Factor Exression of Human Keratinocytes on Microcarrier Beads
Authors: Williams R. , Rees R.S. , Lindblad W.J.
Published: March 2007

Human keratinocytes have been extensively used for the treatment of large body surface area burn injuries. We have studied the potential for treating non‐thermal, chronic wounds with keratinocytes grown on microcarrier beads placed into porous retrievable bags. The current studies were undertaken to examine the growth characteristics of these cells on Cytoline‐1™ microcarrier beads, and how this growth correlated with the expression of growth factors.

Human keratinocytes were expanded in Keratinocyte Basal Medium‐2 with standard supplements (Clonetics, Inc.). The cells were trypsinized and added to Cytoline‐1™(Pharmacia Biotech) beads at 13.3 × 106 cells per mL pre‐equilibrated beads. The beads were seeded into roller bottles and cultured in a humidified 37° C incubator for up to two weeks. Cell numbers were monitored by direct cell counting on the beads following hematoxylin staining; and by protein and DNA content. Aliquots of media were also assayed for levels of PDGF and VEGF by immunoassay (QuantikineR, R&D Systems).

Keratinocytes showed a lag in growth with a sustained decrement in cells per bead from 456 to 346 cells/bead by day 7. This was followed by a robust growth response to 551 cells/bead by day 11. These values correlated with total cellular protein (994, 738, and 1164 ug); and DNA content. The secretion of PDGF and VEGF by human keratinocyte under these conditions, did not directly correlate to the cell number but rather indirectly to the increase in cell number after the 7 days of stagnant growth. These results suggest that the vulnerary effect observed with human keratincytes on microcarrier beads is dependent on acculturation of the cells to the microbead environment, after which they begin to express elevated levels of growth factors important for healing.
066 Fixation of Autologous Skin Grafts Without Staples or Sutures – Experimental Study
Authors: Mittermayr R. , Wassermann E. , Thurnher M. , Simunek M. , Redl H.
Published: March 2007

The objective of the study was to evaluate the efficacy of skin graft fixation with fibrin sealant (FS) alone by means of spray application with a low setting time (thrombin concentration 4–5 IU/ml) in comparison to point suture fixation as a clinical reference method. Furthermore, the influence of two different quantities of FS were tested.  Material and Methods: On the dorsum of 6 male pigs four full‐thickness wounds (8 × 4 cm) were excised in each animal. Randomly the four defects were divided into 3 groups (FS 0.05 ml/cm2; FS 0.15 ml/cm2(Tisseel, Baxter AG, Vienna, Austria); Suture) and covered with autologous split thickness skin grafts. Outcome measurements included hematoma/seroma formation, graft dislocation, wound contraction, graft take rate and healed wound area. Observational time points were the 5th, 14th and 21st postoperative day. Results: Hematoma formation on day of surgery was more pronounced in the suture group (FS 0.05 ml/cm2 vs. suture, p < 0.05), similar the situation on the 5th postoperative day but without statistical significance. Graft dislocation revealed marked but not significant extended area in the suture group vs. the FS 0.05 ml/cm2 group. The FS 0.05 ml/cm2 graft take on day 5 was found to be enhanced in comparison to the suture group. Excellent wound healing was notable on final observation day in the FS 0.05 ml/cm2 group with a healed wound area of 99.7 (3.6/0.3). Corresponding values in the FS 0.15 ml/cm2 was 96.9 (4.7/2.1) and 95.9 (2.7/2.1) for the suture group. Values represents median (Q1/Q3).  Conclusion: The application of a thin layer of FS (0.05 ml/cm2) in a low setting rate (4–5 IU thrombin) in split thickness skin transplantation via a spray device shows comparable results to those yielded with suture point fixation (surrogate for staples). Advantages are e.g. better cosmetic results and initial hemostasis with minimizing the incidence of early hematoma formation. Equal properties of manufactured low thrombin (4 IU; Canada) preparation vs. 500 IU (US) diluted to a 5 IU thrombin solution was also demonstrated.
070 Epidermal Wound Healing is Delayed in Streptozotocin Induced Diabetic PIGS
Authors: Velander P. , Hoeller D. , Theopold C. , Gheerardyn R. , Bleiziffer O. , Yao F. , Eriksson E.
Published: March 2007

Streptozotocin‐induced diabetes is a well established model of diabetes in rodents. However, these small mammals differ from humans in a number of anatomical and physiological ways, in contrast to pigs, who are more similar to humans. No diabetic pig model has been used for the study of wound healing. Our hypothesis is that re‐epithelialization would be delayed in the streptozotocin induced diabetic pig.

Method: Diabetes was induced by injecting Streptozotocin into two three month old female Yorkshire pigs. 52 full thickness wounds were created on the dorsum and dressed with polyvinyl chambers to keep the wounds wet and to allow for wound fluid monitoring. Serum glucose and wound fluid glucose concentrations were monitored daily. Wound contraction was monitored and biopsies taken on multiple days for re‐epithelialization measurements.

Results: The serum glucose was significantly increased for the duration of the experiment (>350 mg/dl). Wound fluid glucose closely followed serum glucose concentration. There was no statistical difference between the contraction rates of wounds in diabetic pigs and healthy pigs. Re‐epithelialization was significantly delayed in diabetic wounds.

Reepithelialization
Day 12
Day 14
Day 16

Diabetic pig
38%
59%
82%

Healthy pig
96%
100%
100%

Conclusion: Epidermal regeneration of full thickness wounds is significantly delayed in the Streptozotocin induced diabetic pig. This is a very useful model of impaired wound healing because of the close similarity to human skin. The wound chambers add the advantage of monitoring and manipulating the wound environment.
078 Mechanical Strain Induces Hypertrophic Scars in Mice by Reducing Stromal Cell Apoptosis
Authors: Bhatt KA , Greives MR , Galiano RD , Ashinoff RL , Bonillas RG , Ceradini DJ , Jones DM , Levine JP , Gurtner GC
Published: March 2007

Intro: Pathophysiology of hypertrophic scar formation remains unclear, potentially involving mechanical strain, burns, or infection. We sought to specifically examine the role of mechanical strain in hypertrophic scars. To do so, we developed and characterized a novel murine model which uses mechanical strain to produce hypertrophic scars in mice.

Methods: Paired incisions were created on C57BL6 mice (n = 20). After closure, mechanical strain was applied across one wound using a novel device; the other wound was a control. Starting at day 3, mechanical strain was increased every other day over 4 wks. Wounds were harvested each week, and examined histologically using Sirius red, DAPI, BrdU for proliferation, and caspase 3 for apoptosis.

Results: Strained wounds showed features of hypertrophic scars: raised borders, loss of rete pegs and adnexal structures in the epidermis overlying scars, blood vessels that were perpendicular and fibrillary collagen that was parallel to skin surface. Features persisted beyond 6 months. Wound collagen deposition in strained wounds increased 6‐fold at 1 wk and over 12‐fold at 2–4 wks, in parallel to an increase in number of stromal cells within scar (28‐fold). This resulted in an increase in number of cells per unit area of collagen (over 42%). In all wounds, there was no significant difference in proliferation. There was a significant reduction in blood vessel (4‐fold) and fibroblast (3‐fold) apoptosis at 1–4 wks in strained wounds.

Conc: Mechanical strain alone is sufficient to produce hypertrophic scars in this model that are indistinguishable from human scars. Notably, hypertrophic scars appear to result from a marked reduction in apoptosis, rather than from a significant proliferation and upregulation of cellular collagen deposition, validating previous in vitro studies.
079 MMP 9 Mediates Angiopoietin‐1 Recruitment of Endothelial Progenitor Cells to Diabetic Wounds
Authors: Keswani SG , Parvadia JK , Kozin ED , Malik A , Zoltick PW , Radu A , Alaee D , Katz AB , Crombleholme TM
Published: March 2007

Introduction: Adenoviral gene transfer of Angiopoietin‐1 (AdAng1) recruits endothelial progenitor cells (EPCs) and improves diabetic wound healing. A suggested mechanism for EPC mobilization from the bone marrow (BM) is mediated through MMP‐9 and stem cell factor (SCF). We hypothesize that Ang‐1 recruits EPCs to diabetic wounds via an MMP‐9 dependent mechanism.  Methods: Lethally irradiated mice were reconstituted with BM from transgenic TIE‐2/LacZ mice. After engraftment, diabetes was induced with steptozotocin. 8 mm wounds were created in BM transplanted (BMT)(n = 12) or MMP‐9 knockout (KO)(n = 12) mice and treated with 1 × 108 PFU of AdAng1, AdGFP or PBS. At 7 days wounds were analyzed for epithelial gap, vessel density, and EPCs. Serum levels of VEGF, proMMP9 and SCF were assessed. Data are expressed as mean ± SEM  Results: In diabetic BMT wounds, AdAng1 results in improved reepithelialization (Ang1 2.3 ± .2 mm; GFP 3.9 ± .2; PBS 4.0 ± .1 p < .0001) neovascularization (Ang1 6.8 ± .3Caps/Hpf; GFP 3.0 ± .4; PBS 2.9 ± .3 p < .0001) and EPC recruitment (Ang1 5.3 ± .4 EPCs/Hpf; GFP 2.1 ± .3; PBS 2.2 ± .3 p < .0001). AdAng1 treatment results in increased levels of proMMP‐9 (Ang1 9.7 ± .8 ng/ml; GFP 6.3 ± .9; PBS 6.4 ± .4 p < .01) and SCF (Ang1 265 ± 28 pg/ml; GFP 119 ± 16; PBS159 ± 12 p < .001). In MMP9 KO mice, AdAng1 accelerates reepithelialization (Ang1 3.2 ± .1 mm; GFP 4.1 ± .2; PBS 3.8 ± .2; p<.) but has no significant effect on neovascularization (Ang1 4.1 ± .5 Caps/HPF; GFP 3.9 ± .4; PBS 3.9 ± .6), EPC recruitment (Ang1 2 ± .3 EPC/Hpf; GFP 1.5 ± .3; PBS 1.6 ± .2) or SCF levels (Ang1 83 ± 5 pg/ml; GFP 83 ± 2; PBS 88 ± 6).  Conclusions: The effects of Ang‐1 on EPC recruitment and neovascularization are dependent on MMP‐9. Our data support the hypothesis that MMP‐9 enables SCF to permit mobilization of EPCs.
092 Arp2/3 Messenger RNA Localization and Fibroblasts Migration in Culture and in Rat Healing Wounds
Authors: Liu Gang , Mingle Lisa A. , Okuhama Nataly N. , Van De Water Livingston , Harmon Robert
Published: March 2007

Directed cell migration plays an important role in wound healing and many other cellular processes. To move directionally, a cell must become asymmetric and establish a dominant protrusion in which localized actin polymerization is a hallmark. We demonstrate that Arp2/3 protein complex, an actin polymerization nucleator consisting of seven protein subunits, is localized to the leading protrusions of cells in culture and in rat healing wounds. The localization of the Arp2/3 protein complex is consistent with its function to promote protrusion and migration. However, the mechanism that restricts the localization of this complex in migrating cells remains unknown. We demonstrate that messenger RNAs (mRNAs) for all the seven subunits of the Arp2/3 complex are localized at the leading protrusions of cells in culture and in wounds. This is the first evidence that mRNAs encoding a protein complex are co‐localized to a common site of function. Interestingly, mRNA for Dia‐I, a formin protein and another actin nucleator for actin bundles (such as stress fibers), is not localized. Such differential localization of mRNAs for the two actin nucleators suggests that these two functions are sequestered by mRNA sorting. We also demonstrate that the Arp2/3 mRNA localization is dependent on both the actin and microtubule cytoskeletons because disrupting either system abolishes Arp2/3 mRNA localization. The expression and localization of Arp2/3 mRNAs are dependent on serum, indicating Arp2/3 mRNA expression and sorting are consequences of a cellular response to the extracellular environment. Current work focuses on identification of the localization signal sequences and the physiological significance of Arp2/3 mRNA sorting in directed fibroblasts migration.
102 Effects of Type II Collagen and Basic‐FGF on Cartilage Wound Healing in a 3D Defect Model
Authors: Chen C.W. , Tsai Y.H. , Zuo C. , Lai W.F.
Published: March 2007

Cartilage preserves limited regenerative capacity and results in insufficient healing after joint injury. Previous researches showed that biocompatible materials and growth factors enable to facilitate cartilage repair; however, the mechanisms of cartilage regeneration are still not completely understood. The purpose of this study was to determine the effects of extracellular matrix and growth factor on chondrocyte migration and phenotype during cartilage regeneration. Neocartilage, 35 mm in diameter and 1 mm in thickness, was fabricated by using rabbit primary chondrocytes embedded in an in vitro three‐dimensional collagen matrix. Five mm diameter defects were made. The effects of collagen matrices and basic‐FGF on three‐dimensional cartilage wound healing were determined. Results showed that both type I and type II collagen matrices (1 mg/ml) facilitated migration of chondrocytes from surrounding cartilage into the defect area in the presence of 10 ng/ml basic‐FGF. The average of migration speed was 91.5micron/day for type I, and 88.1micron/day for type II collagen matrix in the period of 26 days. Incorporation with basic‐FGF, chondrocytes increased approximately 1.5 times motility in the both collagen matrices. However, the cartilaginous phenotype was noted only when embedded in type II collagen matrix. The results indicate that type II collagen may trigger the redifferentiation during the migration of chondrocytes. Extracellular matrix such as type I and type II collagen, in addition to cytokines such as basic‐FGF, play an important role in the process of cartilage wound healing in a three‐dimensional defect model.
108 HIF‐I and VEGF Regulation in Ischemia
Authors: Procaccini P. S. A. , Jia S. , Roy N. , Mogford J.E. , Mustoe T.A.
Published: March 2007

Epithelialization and vascularization are key elements involved in the repair of cutaneous wounds. One method of regulation for these pathways is expression of a signaling molecule known as Vascular Endothelial Growth Factor (VEGF), which, in turn, is regulated by the transcription factor Hypoxia‐Inducible Factor‐1 (HIF‐1). It has been suggested that chronic wounds, which are most commonly located in ischemic tissue among the elderly, may be the result of a loss of function in the VEGF regulation pathway. Using our rat back flap model, which demonstrates the negative influences of age and ischemia on wound healing, we examined the relative expression of HIF‐1 and VEGF in aged and young rats at 3,7, and 10 days post‐wounding. Four full‐thickness biopsy punches (7 mm) were made on the back of each aged and young rat. The rostral wound pair was made ischemic by raising a transverse flap (1.8 cm wide × 8 cm length). The caudal wound pair served as a non‐ischemic control. Inserting a sterilized polyethylene sheet under both ischemic and nonischemic wounds prevented wound contraction. RNA was extracted from the tissue at the specified time points, and run on Real‐Time PCR to determine relative expression of VEGF and HIF‐1. Preliminary data suggest that, at the 3 day time point, there is a significant increase in both HIF‐1 and VEGF expression in young rats under ischemic conditions and a significant increase in VEGF expression in aged rats under ischemia with a strong (but not significant) trend towards increase in HIF‐1 as well. While the rat model does not produce significant differences between aged and young animals, this upregulation under ischemia indicates that HIF‐1 and VEGF expression may play a vital role in the early signaling of ischemic wound repair.
109 Use of EPR Spectroscopy to Measure Tissue Oxygen in an Ischemic Flap Model
Authors: Gould LJ , Mushkudiani J , Hou H , Grinberg OY , Grinberg S , Swartz HM
Published: March 2007

Methods to reliably measure tissue oxygenation in situ are currently lacking. We have developed a vertically oriented, dorsal, bipedicle flap model that is easy to perform, reliably reproduces tissue ischemia, eliminates craniocaudal variation, and is amenable to studying therapeutic modalities. The effect of narrowing this flap on tissue oxygenation measured with Licox electrodes has previously been presented. In this study we utilize in situ EPR spectroscopy to demonstrate the oxygen gradient in the flap as a function of flap width and placement of a silicone sheet directly under the flap. The effect of wound healing over a 2 week period is demonstrated.

Twenty four, 300 gm male Sprague‐Dawley rats underwent creation of the bipedicle flap according to the following groups: 2.5 cm flap with silicone, 2.0 cm flap without silicone, 2.0 cm flap with silicone. Each group of 6 animals was injected with EMS char at 2 cm intervals along the flap and one injection in the control, non‐ischemic tissue. A 4th group underwent 2.0 cm flaps with silicone and use of lithium phthalocyanin as the paramagnetic material. Wound measurements and EPR spectroscopy were performed on days 3, 7, 10 and 14. On day 14, after EPR measurements, the animals were sacrificed and their wounds excised. One flap and one control wound were preserved for histologic analysis, the other flap and control wounds were prepared for lactate measurements.

EPR spectroscopy demonstrated a gradient of oxygen that was lowest in the center of the flap and greatest at either end. Changes in the oxygen gradient correlated with narrowing and placement of the intervening silicone sheet. This new technology has never been utilized in an animal model of impaired wound healing. Comparison of recently developed paramagnetic materials for optimal tissue oxygen and free radical measurements will be presented.
116 Risk Factors for Pressure Ulcers in Elderly Hospital Patients
Authors: Baumgarten Mona , Margolis D. , Lowe R. , Localio R. , Kagan S. , Holmes J. , Kavesh W. , Kinosian B. , Abbuhl S. , Ruffin A.
Published: March 2007

Elderly hospital patients have ample exposure to situations and procedures that may increase their pressure ulcer risk. The aims of this study were to estimate the incidence of hospital‐acquired pressure ulcers in elderly medical patients and to determine whether the risk of pressure ulcers is associated with longer emergency department (ED) stays, lengthy procedures in the ED, or use of immobilizing restraints, medications, or devices in the ED. The study cohort was made up of 3,233 patients aged 65 or over admitted through the EDs of two Philadelphia hospitals. Sixty‐five percent of subjects were aged 80 or more, 61% were female, and 69% were Black. The incidence of hospital‐acquired pressure ulcers on Day 3 of the hospital stay, as ascertained by direct skin examination, was 6.2%. There were 266 hospital‐acquired pressure ulcers among 201 patients (mean per patient 1.3 pressure ulcers) 27% of the pressure ulcers were stage 1, 54% were stage 2, and the remainder were stages 3 or 4 or could not be staged. The median length of stay in the ED was 6.6 hours. The association between hospital‐acquired pressure ulcers and extrinsic risk factors will be presented. The identification of potentially modifiable risk factors may lead to the development of effective interventions to prevent hospital‐acquired pressure ulcers.
119 Clinical Experience with the Self‐assembled Skin Substitue as a Biological Dressing for Chronic Venous Leg Ulcers Treatment
Authors: Dubé N. , Rochon M.‐H. , Ospina C.E. , Soucy J. , Germain L. , Auger F.A.
Published: March 2007

Introduction: Venous ulcers are the most common chronic wounds of the lower limbs. In our laboratory, the self‐assembly method is used to reconstruct autologous skin that can be used as a biological dressing (In Vitro Cell Dev Bio Anim, 1999: 35, 318; J Chem Eng, 2001: 79, 663).

Goals and Methods: The aim of this study was to establish if our self‐assembled skin substitute (SASS) allows the closure of nonhealing venous leg ulcers. A case study of a 68‐year‐old woman with a chronic venous leg ulcer present for over one year and measuring 135 cm2 is thus herein presented. The autologous cells were isolated from a cutaneous biopsy (1 cm2) and cultivated in vitro(J Chem Eng, 2001: 79, 663). The autologous SASS was produced and assembled by the cells thus it does not contain any exogenous or synthetic material (In Vitro Cell Dev Bio Anim, 1999: 35, 318). The wound was debrided, covered with grafts of SASS and maintained in place with a compressive dressing (Coban, 3M, St‐Paul, MN). A new SASS was applied weekly until wound closure. The SASS seemed to lessen the pain caused by the ulcer. Seven applications of the SASS were necessary to lead to a full wound closure.

Conclusion: Venous leg ulcer quickly reepithelialized after application of our SASS This case indicates that use of the SASS can reduce pain and promote closure of nonhealing leg ulcers Furthermore, we thus hope that our SASS biological dressing maybe clinically useful to treat difficult‐to‐heal leg ulcers. This study was approved by the Health Canada’s Therapeutic Products Directorate and by the Ethic Committee of the CHAUQ, Saint‐Sacrement Hospital.

Acknowledgements: Fédération des Pompiers du Québec pour les Grands Brûlés.
123 A New Study Design to Compare Wound Dressings
Authors: Baldursson Baldur
Published: March 2007

The initial tests of a new ulcer dressing, even if the materials are well known and safe must include comparison with other dressings.

In order to test the performance of a new dressing manufactured to treat medium to heavily exuding wounds we designed a wound model using wounds resulting from harvesting of punch grafts for treatment of chronic ulcers. These are usually made by a 6 mm wide biopsy punch and a scalpel and are 7 mm wide round split skin wounds reaching down to the reticular dermis in a number from 2–300.

10 consecutive patients with leg ulcers that had a punch graft operation performed at the in‐patient Dermatology ward in Reykjavik, Iceland were enrolled. The grafts were harvested on the antero‐lateral aspect of the thigh in a pattern of three groups each with 3–20 punch graft wounds. A different type of wound dressing was used to treat each group. Dressing changes were scheduled for one, four, 12 and 18 days after the operation.

The nurse graded the appearance of the split skin wounds into infected or non‐infected, inflammatory or non‐inflammatory. The patient graded the degree of pain at dressing removal using a visual assessment scale.

The dressings were weighed before and after to assess fluid absorption. Detailed digital photographs recorded the progress of each group of donor sites.

The outcome of the different parameters seemed consistent and repeatable.

Using the donor site of punch grafts is a repeatable and consistent way of studying the performance of new ulcer dressings, comparing them to established dressings.
129 A Summary of Scientific Studies and Clinical Results with a Glycerine Based Dressing
Authors: Stout E.I.
Published: March 2007

The importance of controlling the bioburden in wounds can not be over emphasized. Glycerine based gel sheets have been used extensively to show their bacteriostatic/fungistatic properties. Hoekstra studied animal wounds and compared glycerine dressings with water based dressings and the glycerine showed superior bioburden reduction. Vandeputte showed similar results when comparing hydrogel and hydrocolloid dressings and looked at the histology of the wounds to find differences in the quantities of the types of cells present. The reduced scar formation of wounds are thought to be attributed to the influence of the glycerine on the healing process. Hoestra has reported the dramatic reduction in the inflammation reaction soon after application of the glycerine gel dressing. Studies by Oliveria‐Gandia, Davis, and Mertz showed the glycerine dressings to be more effective than hydrogel or hydrocolloid dressings in reducing bioburden in animal wounds that were inoculated with microbes and also reducing biocounts in appropriate growth medium. Vandeputte conducted a diabetic study(no exclusions) that compared the glycerine dressing (n = 15) with standard protocol(n = 14) for diabetic foot wounds, that showed the test dressing to be far superior. He along with thousands of other nurses around the world have reported the use of glycerine dressings on superficial burns to reduce pain, reduce the chance for infection, reduce scar formation, and to protect the wound from friction and pressure. J. Baksa extensively used the glycerine gel sheets in his burn unit not only for the superficial wounds but also for 3rd and 4th degree burns on children as well as after surgical removal of hypertrophic and keloid scars to prevent reoccurrence. T.M. Baum and M.J. Busuito also reported the use of the glycerine dressing for scar prevention and treatment. The glycerine dressing has been used extensively for te treatment and prevention of pressure ulcers in hospitals, nursing homes, athletic fields, as well as, under casts, splints and braces. R. Horchner reported a >95% reduction in pressure ulcers in a direct comparison to the control and to hydrocolloids.
004 Novel Platelet Concentrate Preparation System for Growth Factor Mediated Wound Healing
Authors: Sukavaneshvar S , Zheng Y , Mohammad SF
Published: March 2007

A promising approach for advanced wound healing involves the use of growth factors from autologous platelet concentrate (PC). A novel PC (NPC) preparation technique, based on platelet aggregation and filtration, has been developed to concentrate platelets (in less than 5 minutes) in a fully disposable system, eliminating the need for a centrifuge or cell saver.

NPC was compared with centrifugation‐based PC (CPC) with regard to: 1) platelet recovery, 2) growth factor content, 3) cell proliferative activity with monkey epithelial cells and bone‐marrow mesenchymal cells (BMMC), 4) healing response of Porcine full‐thickness wounds.

There was no statistically significant difference in platelet count, growth factor content (platelet‐derived growth factor enzyme‐linked immunosorbent assay), and cell proliferation activity (Fig. 1) between NPC and CPC. Quantitative assays (Alkaline phosphatase and 5‐bromo‐2‐deoxyuridine) in BMMCs also showed that NPC was equal to CPC in its mitogenic activity (n = 6, paired t‐test).

 Images showing similar cell growth with NPC and CPC.

image

The histopathology of porcine full‐thickness wounds (at 24 days) showed that NPC and CPC (in a hydrogel carrier) treated wounds healed similarly. The NPC and CPC treatments resulted in less scarring, less inflammation, and improved vascularity than hydrogel alone.

The NPC’s growth promoting ability is equivalent to CPC, and the technique is significantly simpler, faster, and more economical than CPC. Thus, NPC could dramatically expand the use of PC for wound healing when combined with various wound dressings and adjuvants.
137 The cutaneous “Underlying disorder” in diabetic rats
Authors: Lu S.L. , Qing C. , Xie T. , Wang M.J. , Niu Y.W. , Ge K. , Jin S.W. , Liao Z.J. , Shi J.X.
Published: March 2007

Objective To investigate the histological characteristics and pathophysiological changes in diabetic skin.  Methods: 12 Sprague‐Dawley rats weighing 200–220 g were divided into control and STZ‐induced diabetic groups. The shaved skin specimens from the back of rats were collected on 8 w post STZ‐inducing. The cutaneous histological characteristics were observed. The local contents of glucose, advanced glycation end products(AGEs) and hydroxyproline, the levels of aMMP‐2 and TIMP‐2, and the cell cycles of both keratinocytes and dermal cells were determined.  Results: The thicknesses of epidermis layer and dermis layer were both reduced obviously in diabetic skin, with the morphological characteristics of the obscured multilayer epithelium features and the decreased amount of spinous in epidermis; the atrophied, swollen and degenerated collagen fibers with a focal chronic inflammatory cells infiltration. The results also revealed that contents of glucose, AGEs, the level of aMMP‐2 and the ratio of aMMP‐2/TIMP‐2 in diabetic skin were higher than those in the controls. In diabetic group, the percentages of S stage and G2/M stages of keratinocytes were obviously decreased, while the dermal cells showed the higher percentage of S stage and the normal percentage of G2/M stages, when compared with the control group.  Conclusion: The cutaneous histological and pathophysiological alterations in diabetes mellitus has already been occurred when exogenous damage is not existed, which presented an “underlying disorder” characteristics in diabetic skin. The cutaneous “underlying disorder” in diabetes might be a critical risk factor leading to ulceration and one of the most important mechanisms in the pathogenesis of impaired wound healing.
140 Microarray Expression Analysis of Fetal Mouse Skin Development: Implications for Scarless Healing
Authors: Yun R , Kong W , Faudoa R , Xia W , Krummel TM , Longaker MT , Lorenz HP
Published: March 2007

Introduction: Fetal mouse skin wounds heal without scar before gestational day E17. Because scarless repair is inherent to fetal skin and occurs superimposed on skin differentiation, genome‐wide gene expression during skin development was tested.

Methods: Dorsal skin from BALB/C mice fetuses at E14, E15, E18 and E20 was collected. RNAs from individual fetuses were hybridized to mouse microarrays with 42,000 gene elements. The E14/E18 hybridizations were repeated three times, and the E15/E20 repeated twice with different samples. (“x” = fold change).

Results: Increased genes on E18 and E20 were clustered into several groups: 1) ECMs: type I (2.8x), III (2.3x), VI, and XIV procollagens; 2) Cell surface: integrin beta1 binding protein2 (5.2x), integral membrane protein2A and 2B (avg 3.8x); 3) Proteases: mast cell protease4 (15x) and 5 (24x), MMP23 (3x); 4) Growth factor‐related: acidic FGF (3.7x), FGF receptor3 (2.9x), TGF‐alpha (2.3x).

Decreased genes on E18 and E20 included: 1) Growth factors: TGF‐beta2 (0.42x), PDGF‐alpha (0.41x), PDGF receptor‐beta (0.37x), NGF receptor associated protein (0.18x); 2) Proteases: MMP 11 (0.27x), 14 (0.39x); 3) ECM: fibromodulin (0.5x), Vcam1 (0.22x), keratin18 (0.2x) and 19 (0.46x), collagen XVIII (0.36x).

Conclusions: Genes with increased expression at E14, E15 and decreased expression at E18, E20 have possible antifibrotic function. These data identify hundreds of possible anti‐fibrotic and pro‐fibrotic genes as candidates for further functional analysis as regulators of repair.

Supported by NIH DE00463–03
141 HB107: A Pre‐Clinical Therapeutic Peptide
Authors: Harris Scott M , Zhang Lijuan , Parente Jody , Gallo Richard L. , Lee Phillip H. A. , Falla Timothy J.
Published: March 2007

Peptides of the innate immune system play a vital role in the protection and repair of almost all biological systems. Such peptides have been implicated in a range of activities associated with prevention of disease and modulation of innate immunity. HB107 is a derivative of one such peptide, Cecropin B, that has demonstrated efficacy in enhancing wound healing in both burn and incision animal models. HB107 has been evaluated for efficacy in a mouse incision model and for safety and efficacy in a pig burn wound model. Topical application of the peptide gives RE50(time needed for 50% re‐epithelialization) values of 10.28 days for 500 ug/mL and 12.72 days for 100 ug/mL compared to control 16.45 days. Additionally the peptide was well tolerated in terms of safety both topically and in an IV acute toxicity mouse model with no adverse effects observed. HB107 not only demonstrated efficacy and safety, but due to being a relatively short synthetic peptide, costs significantly less to manufacture than the current approved therapies.
145 Biological Effects of Calreticulin on Wound Repair
Authors: Gold L.I. , Michaels J. , Callaghan M.J. , Galiano R.D. , Rahman M. , Gurtner G.C. , Nanney L.B.
Published: March 2007

Calreticulin (CRT) is a major classic Ca‐binding chaperone protein of the endoplasmic reticulum. Recently, CRT has been recognized to have widespread extracellular effects as well. In the current study we show that CRT increases both epithelial migration and granulation tissue formation in models of porcine and murine wound repair. Partial thickness wounds were created on the paravertebral area of pigs (n = 4) and 0.1% and 0.5% CRT, and PDGF (positive control) applied for 4 consecutive days. In wounds harvested at 5 days, CRT induced a 28 and 22% greater extent of reepithelialization than PDGF and Tris/Ca buffer control, respectively (% healed = 56/CRT; 40.5/PDGF; 44/control). In addition, CRT stimulated earlier granulation tissue formation in a dose‐dependent manner (cumulative dermal depth, microns: 1615/CRT; 1250/PDGF; 1325/control). A similar granulation tissue inducing effect of CRT was also observed in a steroid‐impaired pig model. As a diabetic model of wound repair, two 5 mm circular full‐thickness wounds were created on the dorsum of db/db mice; the wounds were splinted open with silicone rings and covered with occlusive dressing (n = 24). After 5 days of treatment with 0.1, 0.5, and 5% CRT, a dose‐dependent 8‐, 4.5‐, and 2‐fold increase in granulation tissue formation was observed (p < 0.05). However, there was no apparent effect on wound closure. Tissue sections showed a highly cellular dermis in the CRT treated wounds. In addition, CRT (50 pg/ml) stimulated wound closure in a scratch plate assay using fibroblasts by 45%, in 48 hrs, compared to 2% for the control. Therefore, CRT may be a novel agent for wound healing by acting as a chemoattractant for cells involved in wound remodeling and in epithelial migration.

Suppported by Calretex, LLC. NJ, USA (LIG) and the Alumni Fund, Alumni Association Downstate College of Medicine (MJC).
020 Venous Leg Wounds Managed with Complex Extracellular Matrix
Authors: Mostow Eliot N.
Published: March 2007

Although collagen wound dressings have been used clinically for many years, wound matrix materials comprising the full complement of extracellular matrix molecules have not. Oasis® Wound Matrix (Oasis), a complex, growth factor‐containing matrix derived from the intestinal submucosa of pigs, has shown promise as a treatment to manage full‐thickness, hard to heal wounds. A multi‐center, prospective, randomized clinical trial was conducted to compare the effectiveness of Oasis to a standard of care (SOC) regimen consisting of compression therapy, weekly dressing changes and debridement (as needed) for the treatment of venous leg ulcers. Incidence of healing within 12 weeks, as defined by full epithelialization without drainage, was the primary outcome measure. Significance was determined by the proportion of ulcers healed using Fisher’s Exact Test. This interim data included 84 evaluable patients (45 Oasis, 39 SOC). Incidence of healing at 12 weeks was 71% in the Oasis group versus 46% in the SOC group. Fisher’s Exact Test yields a significant p‐value of 0.018. These results clearly demonstrate that the healing of these hard‐to‐heal wounds is markedly improved when Oasis wound matrix is used as part of the wound treatment program as compared to standard of care alone.
024 Effects of an Electrical Stimulation Bandage on Wound Healing
Authors: Jennings J.A. , Feldman D.S. , Andino R.V.
Published: March 2007

Although electrical stimulation (ES) has been successful in the treatment of various types of wounds, the popularity of the treatment has waned due to a lack of optimal methods of administration. The goal of this study has been to develop and evaluate a method of delivering ES that is easy to use and suitable for delivery in a home‐health environment.[0] Specifically, a novel bandage system developed to provide an electric field in a manner resembling the natural wound current was tested in vivo. In this study, a full‐thickness wound model in New Zealand white rabbits was used to measure the effects of such a bandage system on healing of [0]skin defects. Different levels of current were evaluated initially, with 50 and 20 μA selected for the focus of this study, along with a non‐stimulated control. Using histomorphometry healing rates, cellularity, and blood vessels were quantified at one and two week time points.

The study showed the ability of this ES bandage to speed the healing process. An increase in overall healing rate over non‐stimulated wounds of 45%(p = 0.04) was observed in wounds stimulated with 50 μA of current for 1 week. In wounds treated for 2 weeks, contraction rate decreased as well as the ratio of contraction rate to epithelialization rate. The stimulated wounds also showed an increase in the amount of macrophages, with a 79% increase in number of macrophages in wounds stimulated with 20 μA for 2 weeks and a 198% increase in macrophages in those stimulated with 50 μA compared to non‐stimulated wounds. The performance of the bandage in the animal model has led to a limited clinical study on pressure ulcer patients using the 50 μA system.

Acknowledgements: This project was funded through Biofisica and the CDC through NCIPC.
025 Modulation of Wound Repair in the Obese Diabetic Mouse: a Role for VEGF Gene Transfer
Authors: Schwartz SB , McCampbell B , Garone R , Vodslon Z , Tokarcsik E , Coico J , Staiano‐Coico L
Published: March 2007

Identifying molecular loci of impaired cutaneous healing in diabetes with an eye towards developing targeted therapy to ameliorate dysrepair continues to evolve as a promising area of study. By using an excisional wound model produced on the dorsum of female diabetic C57BL/KsJ db + /db+ mice as well as their normal (WT) & heterozygous (HZ) littermates, we studied the effects of peri‐wound intradermal injection of adeno‐associated viral vector (AAV) expressing the 165‐amino acid isoform of human vascular endothelial growth factor (VEGF) on the following: kinetics of re‐epithelialization, neoangiogenesis and granulation tissue formation, matrix remodelling, collagen deposition, and maturation. One sq. in. full thickness excisional wound was created in the mid‐upper back, rendering half of the wound as either right or left paravertebral. Animals were randomized to receive 1 of 3 treatments via intradermal injection: 1)VEGF (AAV) vector; 2)Adnull vector; 3)PBS. Postoperatively, wounds were examined & photographed on Days 3, 7, 10, 14, 21 & 28. Also, tissue was harvested for histology & immunohistochemistry (PECAM), and snap frozen for protein & RNA analysis. A scoring system was used to grade re‐epithelialization, granulation tissue thickness, matrix density, inflammation, vascular density, epithelial maturity. AAV‐VEGF exerted minimal effect on repair in WT and HZ mice. However, pronounced neovascularization, thickened granulation tissue & increased matrix deposition was noted after VEGF treatment in the db/db mice compared to those that received PBS or adnull vector at all timepoints. While the induction of angiogenesis in VEGF treated db/db mice lagged behind the unimpaired mice by 5–7 days, a global improvement in wound healng was observed.

R Crystal, Dir Inst Genetic Medicine, Weill Med College‐Cornell Univ
Anaesthesia for Shy—Drager syndrome
Authors: HUTCHINSON R. C. , SUGDEN J. C.
Published: March 2007

Anaesthesia for nephrectomy in a patient with Shy–Drager syndrome is described. The potential problems and pre‐, per‐ and postoperative management are discussed with particular reference to the monitoring of cardiovascular function by pulmonary artery catheterisation.
Medishield AGS system and servo 900 ventilators
Authors: GRAY W. M. , HALL R. C. , CARTER K. B. , SHAW A. , THOMSON W. J.
Published: March 2007

The use of the new Medishield anasthetic gas scavenging system with ventilators in the Siemens‐Elema Servo 900 series was investigated. It was discovered that this combination of equipment creates the hazard that a disconnexion in the patient breathing system may not be detected by the ventilator alarm. This happens because the suction generated by the scavenging system draws a considerable flow of room air through the expiratory system of the ventilator when a disconnexion occurs. Possible solutions to the problem were investigated, and it was discovered that the problem can be overcome by applying a small amount of positive end‐expiratory pressure to counteract the suction from the scavenging system.
A modification of a standard laryngoscope for difficult tracheal intubation in obstetric cases
Authors: JELLICOE J. A. , HARRIS N. R.
Published: March 2007

An adaptor is described which can be fitted to a standard laryngoscope to overcome the difficulty associated with tracheal intubation in certain obstetric cases.
General anasthesia for trans‐bronchial lung biopsy
Authors: Barr A. Marshall , Kurer F.L.
Published: March 2007

A technique of general anasthesia is described which has been used for trans‐bronchial lung biopsy in 100 patients. Sixty‐seven were day cases. An early pneumothorax was detected in four patients, but only one needed tube drainage.
Caudal analgesia in children
Authors: HATCH D. J. , HULSE M. G. , LINDAHL S. G. E.
Published: March 2007

The influence of caudal analgesia on pulmonary ventilation and gas exchange was studied in 26 children during halothane anasthesia with spontaneous breathing. Two groups of children were studied with 13 patients in each group. One group received caudal analgesia. The other group had no caudal blocks. All children were subjected to lower abdominal and genital surgical procedures. Minute ventilation and respiratory rates were significantly lower in the caudal group than in the non‐caudal group. Wastea minute ventilation and VD//VT ratios were increased in the non‐caudal group. The end tidal carbon dioxide concentration was unchanged in both groups. The lower minute ventilation in the caudal group eliminated the same amount or even greater amounts of CO2 per minute indicating an improved gas distribution at slow respiratory rates. The improved ventilation efficiency and the excellent immediate postoperative pain relief achieved by caudal analgesia justifies its frequent use for these operative surgical procedures.