BACKGROUND: Open wounds affecting the distal part of limbs are commonly seen in horses. Due to certain factors, such as limited connective tissue available, potentiated growth of excessive granulation tissue, risk of contamination, and poor response to common treatments, healing of these wounds becomes a major problem for veterinarians on a number of occasions. Application of Mesenchymal Stem Cells (MSC) for enhancing wound healing has received a great deal of scientific attention. Among the MSCs, those derived from adipose tissue are frequently used owing to their availability, large number of cells after the primary harvest, and the capacity to differentiate to different cell lines.OBJECTIVES: The current study aimed to evaluate type 1 and 3 collagen genes expression in horse distal limb wounds treated via adipose-derived Mesenchymal Stem Cells and its comparison with bone marrow-derived stem cells.METHODS: After treatment of the experimental open wounds created in the distal limbs of four horses via autologous MSCs, real-time PCR was used for evaluating and comparing the expression of type I and III collagen genes in the healing wounds.RESULTS: Significant differences in the expression of type I and III collagen genes were observed between the treatment groups. Despite the fact that the greatest collagen genes expression belonged to bone marrow-derived MSCs, no significant differences were seen with adipose-derived MSCs.CONCLUSIONS: Owing to the advantages and an acceptable performance, adipose-derived MSCs could be considered as a novel approach to enhancing limb wound healing in horses.

BACKGROUND: Flufenamic acid is a member of the fenamates and is used as an analgesic and NSAID drug. According to the ability of this drug on blocking connexin and preventing leakage of substances such as ATP from cells, it seems to be beneficial in healing diabetic wounds. OBJECTIVES: Evaluation of the effects of topical flufenamic acid as a connexin-channel blocker on skin wound healing in alloxan-induced diabetic rats. METHODS: In this study diabetics was induced in 40 male rats by IP injection of 150mg/kg of alloxan and they were divided to 4 groups. After anesthesia, 2×2 cm incision was made on the back of the rats and the skin was separated completely. Three groups were treated by 2, 5 and 10 percent concentration of flufenamic acid ointment separately, and one group was treated by Vaseline and ucerine ointment as control. Bandage and ointment were changed daily and the procedure was carried out for 21 days. The wound surface was measured on odd days. Half of the rats of each group on day five and half of them on day 21 were euthanized to get pathologic slides. RESULTS: Process of healing, fibroblast concentration, epithelialization, angiogenesis, collagen formation and wound closure in 2 percent group were better than other groups and in control, 5 and 10 percent groups had a decreasing trend respectively and had a significant difference. In the last two groups, the healing process was disrupted. CONCLUSIONS: The 2 percent concentration of drug not only did not show potent anti-inflammatory effects, but also improved the process of healing by blocking the connexin 43 and inhibition of ATP release, while in the concentration of 5 and 10 percent, anti-inflammatory effects of the drug predominated and delayed the healing process.

A 10-year-old, spayed female, Maltese dog presented with a 2-day history of severe left eye squint. Slit-lamp biomicroscopy showed a deep corneal defect stained into a doughnut shape together with hypopyon in the anterior chamber. Based on these results, a diagnosis of descemetocele and uveitis in the left eye was made. Deep keratotomy combined with a nictitating membrane flap effectively resolved the descemetocele without complications. The surgical procedures performed on this patient were easy and effective, and could be used as an alternative to graft surgery for descemetocele treatment.

The objective of this study was to compare wound healing in stomach with CO₂ laser and scalpel incision by measuring the extent of bleeding, the ease of gastric incision, incision time, degree of adhesion and wound healing degree in dogs. Sixteen healthy dogs were used. Two symmetrical incisions were made in ventral aspect of the stomach between the greater and lesser curvatures were made with scalpel and 0.2 mm spot diameter CO₂ laser (8W, continuous wave) in sixteen dogs. And then each wound was closed with absorbable suture in a two-layer inverting seromuscular pattern. At 3, 7, 14 and 21 days after initial wounding, each wound was taken for histological observation. On surgery, the extent of bleeding, the ease of incision and incision time showed significant differences between the groups. The CO₂ laser provided better hemostasis (p less than 0.05) and smaller postoperative adhesion compared with the scalpel. However, the scalpel produced faster speed of incision and was easier to handle than the CO₂ laser (p less than 0.05). Although there was no considerable difference between the two groups in histological observation, necrosis and calcium deposit tended to be larger in the CO₂ laser than in the scalpel.

This study compared the instrument performance and tissue healing of a steel scalpel with a CO₂ laser in an animal urinary bladder surgery model. Landrace and Yorkshire mixed breed pigs were used. Two symmetrical incisions were made in urinary bladder of each pig. One incision was made on the left side of ventral aspect on urinary bladder using a steel scalpel, while the other incision was performed on the right side using a CO₂ laser with an 8W output power. Each instrument was evaluated clinically for speed, ease of incision, and extent of bleeding. At 7 and 21 days after initial wounding, each wound was taken for histological observations. The scalpel was an easier instrument to use in the confines of the urinary bladder tissue, compared with the laser. However, there was no significant difference between the two groups. The amount of bleeding was less in the laser group but the time of the incisions was shorter with the scalpel. Scalpel incisions showed complete restoration of the epithelium and muscularis. On the other hand, the laser incisions showed incomplete restoration of the epithelium and muscularis. However, most of wound healing in the laser incisions was accomplished according to the time lapse. Although the scalpel produced less damage to the urinary bladder tissue and was easier to handle than the CO₂ laser, it did not provide hemostasis that was helpful for use on highly vascular tissue. The CO₂ laser provided good hemostasis, but delayed wound healing. In conclusion, the CO₂ laser provided better hemostasis and better surgical field than the scalpel. The CO₂ laser was used effectively in urinary bladder incision.

After removal of 1 metatarsal pad and formation of a granulation tissue bed, free segmental 6- X 8-mm grafts from digital pads were sutured into recessed same-size recipient sites in the granulation tissue. In 5 dogs, the grafted area had been denervated by excision of a segment of the tibial nerve at the level of the tarsus. The grafted area was not denervated in the remaining 5 dogs. In both groups of dogs, the grafts placed around the periphery of the wound healed, blocked ingrowth of delicate epithelium from the surrounding skin, and provided a tough keratinized epithelium that covered the wound's center. As healing progressed, the grafts coalesced as the wounds contracted. Weight bearing resulted in graft expansion to provide functional weight-bearing tissue. Dogs of the denervated group had clinical and histologic evidence of collateral sensory reinnervation of the denervated area. However, with the exception of 1 dog, results of sensory nerve action potential tests indicated that reinnervation may not have been by way of regeneration across the excisional gap in the nerve. Evaluation of reinnervation of the tibial autonomous zone in 2 additional dogs revealed clinical evidence that collateral reinnervation began between 19 and 28 days after nerve excision and progressed proximad to distad. Results of sensory nerve action potential tests indicated that reinnervation may not have been via regeneration across the excision site. Results of fluorescent tracer studies did not have positive findings regarding the route of collateral reinnervation. Segmental paw pad grafts can be used effectively to provide weight-bearing tissue on a dog's limb. With local nerve damage on the distal portion of the limb, collateral innervation can grow into the area to reinnervate tissues, including pad grafts.

Wound healing is a fundamental response to tissue injury and several natural products have been shown to accelerate the healing process. The present study was undertaken to determine the safety and efficacy of the topical treatment of acetone leaf extracts of Combretum imberbe, Combretum nelsonii, Combretum albopuntactum and Terminaliasericea based on their in vitro antimicrobial activity. Four circular full-thickness skin wounds were made on the backs of eight anaesthetised Wistar rats using aseptic techniques. The treatments were administrated topically using 10% and 20% concentrations of each extract in aqueous cream in separate treatments. Indications of erythema, exudate, crust formation, swelling and ulceration were used to determine the wound healing process. All of the wounds closed completely within 17 days. Throughout the experiment, a subcutaneous probe was used to determine that the body temperature and body weight of the rats were within the normal range. C. imberbe and C. nelsonii extracts accelerated wound healing, but there was no significant difference in wound contraction using 10% and 20% concentrations of the extracts in cream. The results also showed the potential usefulness of this model to measure accelerating wound healing. The extracts could perhaps overcome defects associated with healing failure in chronic wounds and prevent secondary bacterial and fungal infections.

The primary goal of the would healing is rapid wound closure. Recent advances in cellular and molecular biology have greatly expanded our understanding of the biologic processes involved in wound repair and tissue regeneration. This study was conducted to develop a new sponge type of biomaterial to be used for either wound dressing or scaffold for tissue engineering. We designed to make a comparative study of the wound healing effect of silk fibroin/hyaluronic acid (SF/HA) blend sponge in full-thickness dermal injury model of rat.

The effects of intra-articular administration of methylprednisolone acetate (MPA) on the healing of full-thickness osteochondral defects and on normal cartilage were evaluated in 8 horses. In group-1 horses (n = 4), a 1-cm-diameter, full-thickness defect was created bilaterally in the articular cartilage on the dorsal distal surface of the radial carpal bone. Cartilage defects were not created in group-2 horses (n = 4). One middle carpal joint was randomly selected in each horse (groups 1 and 2), and treated with an intra-articular injection of 100 mg Of MPA, once a week for 4 treatments. Injections began 1 week after surgery in group-1 horses. The contralateral middle carpal joint received intra-articular injections of an equivalent volume of 0.9% sodium chloride solution (SCS), and served as a control. Horses were evaluated for 16 weeks, then were euthanatized, and the middle carpal joints were examined and photographed. Synovial and articular cartilage specimens were obtained for histologic and histochemical evaluation. Gross morphometric evaluation of the healing defects in group-1 horses revealed that 48.6% of the defect in control joints and 0% of the defect in MPA-treated joints was resurfaced with a smooth, white tissue, histologically confirmed as fibrocartilage. This replacement tissue was a firmly attached fibrocartilage in control joints and a thin fibrous tissue in MPA-treated joints. The articular cartilage in joints treated with MPA had morphologic changes, including chondrocyte cluster formation, loss of palisading architecture, and cellular necrosis in both groups of horses. Histochemical (safranin-0) staining intensity was reduced significantly (P < 0.05) in all layers of articular cartilage in MPA-treated joints in groups 1 and 2. In the replacement tissue, intense safranin-O staining was found only in the chondrocyte clusters deep in the tissue of control joints, confirming fibrocartilage repair. Intra-articular administration of MPA in this dosing regimen thus induced degenerative changes in normal articular cartilage and resulted in histomorphologic changes in the repair of full-thickness articular osteochondral defects in horses.

Full-thickness skin wounds were created on the dorsum of both metacarpi in 8 horses. Three topical treatment regimens were studied. All wounds were bandaged with a nonadherent dressing, which was held in place with a snug elastic wrap. Group-A wounds were treated with a proprietary topical wound medication that consisted of a spray and an ointment. Group-B wounds were treated with the same regimen, except the putative active ingredients in the ointment were omitted. Group-C wounds were treated with a dry nonadherent bandage only. Wound dressings were changed every day and the limbs were photographed every other day until the wounds were healed. Specimens of normal skin and biopsy specimens of healed wounds were examined histologically and were assayed for hydroxyproline content. Wound healing measurements quantitated for each wound were number of days to healing, maximal wound size attained, day wound contraction commenced, day epithelium first noticed, rate of wound contraction, final wound size, and fraction of the wound that healed by contraction. The cosmetic appearance of the healed wounds was also graded. Significant differences were not noticed in hydroxyproline content, histologic appearance, or any of the wound healing measurements between treatment groups. The cosmetic appearance of healed group-A and -B wounds was significantly better than the appearance of group-C wounds. The topical treatment regimens studied neither enhanced nor inhibited wound healing in this study.