bluuebunny/crossref_metadata_2025_split huggingface dataset:
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.
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.
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.
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.
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.imageThe 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.
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
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).
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

SummaryAnaesthesia 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

SummaryThe 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.
General anasthesia for trans‐bronchial lung biopsy
Authors: Barr A. Marshall , Kurer F.L. 
Published: March 2007

SummaryA 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

SummaryThe 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.