Rotator cuff injuries are the most common cause of shoulder pain and dysfunction. Ideal animal shoulder models should have similar shoulder anatomy and function as human, and are able to replicate the microenvironment change after tendon injury. At present, a variety of animal models including rat, mouse, rabbit, sheep, canine, bovine, and primate have been used to study the mechanism of rotator cuff injury, effects of different repair techniques, and factors affecting tendon to bone healing. Although large animal models are more anatomically similar to humans, small animal models are more convenient in revealing the biological mechanism of rotator cuff injury and healing. Choosing appropriate animal models based on research objectives and establishing new small animal models play a critical role in revealing the mechanism of rotator cuff diseases and developing novel treating strategies.
Animals ; Cattle ; Disease Models, Animal ; Dogs ; Mice ; Rabbits ; Rats ; Rotator Cuff ; Rotator Cuff Injuries ; Sheep ; Tendon Injuries ; Wound Healing

Susceptibility-weighted imaging (SWI) is a magnetic resonance imaging (MRI) sequence used for evaluating traumatic brain injury (TBI). Although SWI is being increasingly used in veterinary medicine, there are no systematic studies regarding its use. We aimed to evaluate TBI lesions by using conventional MRI and SWI in 11 dogs and determine the correlation between clinical status and conventional MRI or SWI findings. The modified Glasgow coma scale (MGCS) at presentation and a previously used MRI grading system (MRGr; grades 1–6) were used to evaluate the brain lesions, and correlations between MGCS score and each MRGr were assessed. Conventional MRI revealed 23 lesions in 11 dogs with variable MGCS scores (range: 11–17). SWI showed comparable findings for all of the lesions except for subdural hemorrhage, and it revealed additional lesions in four dogs. The median MRGr was 2 on both conventional MRI and SWI. The MRGr of the conventional MRI assessments and the MGCS scores showed a significant negative correlation (r = −0.685). In conclusion, SWI had better TBI lesion-detection ability, but conventional MRI had a better correlation with early clinical status and subdural hemorrhage. Thus, a combination of conventional MRI and SWI examinations can improve TBI diagnosis in dogs.
Animals ; Brain ; Brain Injuries ; Diagnosis ; Dogs ; Glasgow Coma Scale ; Hematoma, Subdural ; Magnetic Resonance Imaging ; Veterinary Medicine

BACKGROUND: Trichloroacetic acid (TCA) is an agent widely applied in dermatology for skin regeneration. To test whether TCA can offer an advantage for the regeneration of oral soft tissue defects, the cellular events following TCA application were explored in vitro and its influence on the oral soft tissue wound healing was evaluated in a canine palate model.METHODS: The cytotoxicity and growth factor gene expression in human gingival fibroblasts were tested in vitro following the application of TCA at four concentrations (0.005%, 0.05%, 0.5% and 1%) with different time intervals (0, 3, 9 and 21 h). One concentration of TCA was selected to screen the genes differentially expressed using DNA microarray and the associated pathways were explored. TCA was injected in open wound defects of the palatal mucosa from beagle dogs (n = 3) to monitor their healing and regeneration up to day 16-post-administration.RESULTS: While the 0.5–1% concentration induced the cytoxicity, a significantly higher expression of growth factor genes was observed after 3 and 9 h following the 0.5% TCA application in comparison to other groups. DNA microarray analysis in 0.5% TCA group showed 417 genes with a significant 1.5-fold differential expression, involving pathways of cell cycle, FoxO signaling, p53 signaling, ubiquitin mediated proteolysis and cAMP signaling. In vivo results showed a faster reepithelialization of TCA-treated wounds as compared to spontaneous healingCONCLUSION: TCA promoted the healing and regeneration of oral soft tissue wound defects by up-regulating the cell cycle progression, cell growth, and cell viability, particularly at a concentration of 0.5%.
Animals ; Cell Cycle ; Cell Survival ; Dermatology ; Dogs ; Fibroblasts ; Gene Expression ; Humans ; In Vitro Techniques ; Mouth Mucosa ; Mucous Membrane ; Oligonucleotide Array Sequence Analysis ; Palate ; Proteolysis ; Regeneration ; Skin ; Trichloroacetic Acid ; Ubiquitin ; Up-Regulation ; Wound Healing ; Wounds and Injuries

BACKGROUND AND OBJECTIVES: The present study investigated whether MSCs derived microvesicles (MVs) or (Exosomes) can exert therapeutic effects on an experimental model of cutaneous injury and explored the underlying involving mechanisms. METHODS AND RESULTS: Three bilateral full thickness circular wounds were created on the back of two groups of dogs using 2-cm dermal punch. The wounds were at least 2.5 cm apart. Saline was subcutaneously injected in 4 places around each wound area in group-I (control), whereas an equal volume of exosomal solution of MSCs derived MVs was similarly injected in group-II. The findings demonstrated that MSCs derived MVs had significantly promoted cutaneous wound healing, collagen synthesis, and vascularization at wound sites. The application of the exosomal solution had not only promoted the generation of newly formed vessels, but also have accelerated their development and maturation leading to a faster healing process. CONCLUSIONS: MSC-Exosomes appeared to be a superior candidate for treating cutaneous wounds than their originator cells, and may represent a promising opportunity to develop a novel cell-free therapy approach that might overcome the obstacles and risks associated with the use of native or engineered stem cells transplantation therapy.
Animals ; Collagen ; Dogs ; Mesenchymal Stromal Cells* ; Models, Theoretical ; Skin* ; Stem Cells ; Therapeutic Uses ; Wound Healing ; Wounds and Injuries*

PURPOSE: The aim of the present exploratory study was to evaluate extraction socket healing at sites with a history of periodontal and endodontic pathology. METHODS: The mandibular 4th premolar teeth in 5 adult beagle dogs served as experimental units. Periodontal and endodontic lesions were induced in 1 premolar site in each animal using wire ligatures and pulpal exposure over 3 months (diseased sites). The contralateral premolar sites served as healthy controls. The mandibular 4th premolar teeth were then extracted with minimal trauma, followed by careful wound debridement. The animals were sacrificed at days 1, 7, 30, 60, and 90 post-extraction for analysis, and the healing patterns at the healthy and diseased extraction sites were compared using radiography, scanning electron microscopy, histology, and histometry. RESULTS: During the first 7 days of healing, a significant presence of inflammatory granulation tissue was noted at the diseased sites (day 1), along with a slightly accelerated rate of fibrin clot resolution on day 7. On day 30, the diseased extraction sites showed a greater percentage of persistent fibrous connective tissue, and an absence of bone marrow formation. In contrast, healthy sites showed initial signs of bone marrow formation on day 30, and subsequently a significantly greater proportion of mature bone marrow formation on both days 60 and 90. Radiographs exhibited sclerotic changes adjoining apical endodontic lesions, with scanning electron microscopy showing collapsed Volkmann canals protruding from these regions in the diseased sites. Furthermore, periodontal ligament fibers exhibited a parallel orientation to the alveolar walls of the diseased sites, in contrast to a perpendicular arrangement in the healthy sites. CONCLUSIONS: Within the limitations of this study, it appears that a history of periodontal and endodontic pathology may critically affect bone formation and maturation, leading to delayed and compromised extraction socket healing.
Adult ; Animals ; Bicuspid ; Bone Marrow ; Connective Tissue ; Debridement ; Dogs ; Fibrin ; Granulation Tissue ; Humans ; Ligation ; Microscopy, Electron, Scanning ; Models, Biological ; Osteogenesis ; Pathology* ; Periodontal Ligament ; Radiography ; Tooth ; Wound Healing ; Wounds and Injuries

PURPOSE: Furcation involvement in the molars is difficult to treat, and has been recognized as a risk factor for tooth loss. Although periodontal regenerative therapies, including guided tissue regeneration and various types of bone grafts, have been applied to furcation defects, the effects of these treatments are limited, especially in large class III furcation defects. The purpose of this pilot study was to investigate the effect of reciprocal autologous root transplantation on periodontal wound healing and regeneration in class III furcation defects in dogs. METHODS: Furcation defects (7 mm wide and 6 mm high) were surgically created after root separation of the unilateral third and fourth premolars in 4 dogs. Eight furcation defects were randomized to receive either reciprocal autologous root transplantation (test) or no further treatment (control). In the test group, the mesial and distal roots were transplanted into the distal and mesial extraction sockets, respectively. The animals were sacrificed 10 weeks after surgery for histologic evaluation. RESULTS: The healing pattern in the control group was characterized by extensive collapse of the flap and limited periodontal regeneration. New bone formation in the test group (3.56±0.57 mm) was significantly greater than in the control group (0.62±0.21 mm). Dense collagen fibers inserting into the residual cementum on the transplanted root surfaces were observed in the test group. Slight ankylosis was observed in 2 of the 4 specimens in the test group on the mesiodistal sides where the root-planed surfaces faced the existing bone. Root resorption (RR) was detected in both the control and test groups. CONCLUSIONS: Within the limits of this study, it can be concluded that reciprocal autologous root transplantation was effective for bone regeneration in class III furcation defects in dogs. However, further studies are required to standardize the approach in order to prevent unwanted RR prior to clinical application.
Animals ; Ankylosis ; Bicuspid ; Bone Regeneration ; Collagen ; Dental Cementum ; Dogs ; Furcation Defects* ; Guided Tissue Regeneration ; Models, Animal ; Molar ; Osteogenesis ; Periodontal Diseases ; Periodontal Ligament ; Pilot Projects ; Regeneration ; Risk Factors ; Root Resorption ; Tooth Loss ; Transplants ; Wound Healing* ; Wounds and Injuries*

Heme oxygenase-1 (HO-1) is a stress-responsive enzyme that modulates the immune response and oxidative stress associated with spinal cord injury (SCI). This study aimed to investigate neuronal regeneration via transplantation of mesenchymal stromal cells (MSCs) overexpressing HO-1. Canine MSCs overexpressing HO-1 were generated by using a lentivirus packaging protocol. Eight beagle dogs with experimentally-induced SCI were divided into GFP-labeled MSC (MSC-GFP) and HO-1-overexpressing MSC (MSC-HO-1) groups. MSCs (1 × 10⁷ cells) were transplanted at 1 week after SCI. Spinal cords were harvested 8 weeks after transplantation, after which histopathological, immunofluorescence, and western blot analyses were performed. The MSC-HO-1 group showed significantly improved functional recovery at 7 weeks after transplantation. Histopathological results showed fibrotic changes and microglial cell infiltration were significantly decreased in the MSC-HO-1 group. Immunohistochemical (IHC) results showed significantly increased expression levels of HO-1 and neuronal markers in the MSC-HO-1 group. Western blot results showed significantly decreased expression of tumor necrosis factor-alpha, interleukin-6, cycloogygenase 2, phosphorylated-signal transducer and activator of transcription 3, and galactosylceramidase in the MSC-HO-1 group, while expression levels of glial fibrillary acidic protein, β3-tubulin, neurofilament medium, and neuronal nuclear antigen were similar to those observed in IHC results. Our results demonstrate that functional recovery after SCI can be promoted to a greater extent by transplantation of HO-1-overexpressing MSCs than by normal MSCs.
Animals ; Blotting, Western ; Dogs ; Fluorescent Antibody Technique ; Galactosylceramidase ; Glial Fibrillary Acidic Protein ; Heme Oxygenase-1* ; Heme* ; Interleukin-6 ; Intermediate Filaments ; Lentivirus ; Mesenchymal Stromal Cells* ; Neurons ; Oxidative Stress ; Product Packaging ; Regeneration ; Spinal Cord Injuries* ; Spinal Cord* ; Transducers ; Tumor Necrosis Factor-alpha

OBJECTIVES: One way to prevent deaths due to rabies is the timely utilization of post-exposure prophylaxis (PEP). Therefore, in addition to an understanding of the epidemiological distribution of animal bites, it is necessary to explore the factors leading to delays in PEP initiation. METHODS: This cross-sectional study was conducted in Iran in 2011, and included 7097 cases of animal bites recorded at the Rabies Treatment Center of the Shiraz University of Medical Sciences using the census method. Logistic regression was used to identify factors associated with delays in PEP. RESULTS: Among the patients studied, 5387 (75.9%) were males. The prevalence of animal bites in Fars province was 154.4 per 100 000 people. Dogs were the most frequent source of exposure (67.1%), and the most common bitten part of the body was the hands (45.5%). A delay in the initiation of PEP was found among 6.8% of the studied subjects. This delay was more likely in housewives (odds ratio [OR], 4.66; 95% confidence interval [CI], 2.12 to 10.23) and less likely in people with deep wounds (OR, 0.65; 95% CI, 0.43 to 0.97). CONCLUSIONS: Although all animal bite victims received complete PEP, in some cases, there were delays. Further, the type of animal involved, the depth of the bite, and the patient’s occupation were the major factors associated with a delay in the initiation of PEP for rabies prevention.
Animals* ; Censuses ; Cross-Sectional Studies ; Dogs ; Epidemiology* ; Hand ; Humans ; Iran ; Logistic Models ; Male ; Occupations ; Post-Exposure Prophylaxis* ; Prevalence ; Rabies* ; Vaccination ; Wounds and Injuries

Recently, the number of cases of animal bite wounds has increased significantly in concordance with an increase in the pet population around the world. The authors report two rare cases of osteomyelitis of the phalanx following cat and dog bites. On initial physical examination, signs of a severe infection were observed. Radiographs of both patients showed the presence of osteomyelitis, and in one of the patients, the diagnosis was confirmed with a bone biopsy. After use of empirical antibiotics, intravenous antibiotic therapy that matched the identified bacterium's sensitivity was initiated, and at the same time, secure dressing including debridement was performed to induce secondary healing. In addition, the patients were closely monitored with serial X-rays, and culture and blood test follow-up. One patient fully recovered without sequelae, but the other patient suffered a loss of distal interphalangeal joint motion. When dealing with bite wounds located on the hand, it is important to visit the hospital as soon as possible and receive the appropriate treatment early. Moreover, to prevent severe complications such as osteomyelitis, it is important to administer antibiotic therapy to which the cultured bacteria are sensitive, along with proper wound management and prophylactic antibiotic treatment.
Animals ; Animals, Domestic* ; Anti-Bacterial Agents ; Bacteria ; Bandages ; Biopsy ; Bites and Stings ; Cats ; Debridement ; Diagnosis ; Dogs ; Follow-Up Studies ; Hand Injuries ; Hand* ; Hematologic Tests ; Humans ; Joints ; Osteomyelitis* ; Physical Examination ; Wound Infection ; Wounds and Injuries

This study was conducted to identify the effectiveness of platelet-rich plasma (PRP) and efficacy of intralesional injection as a method of application to acute cutaneous wounds in dogs. Healthy adult beagles (n = 3) were used in this study. Autologous PRP was separated from anticoagulant treated whole blood in three dogs. Cutaneous wounds were created and then treated by intralesional injection of PRP in the experimental group, while they were treated with saline in the control group on days 0, 2 and 4. The healing process was evaluated by gross examination throughout the experimental period and histologic examination on day 7, 14 and 21. In PRP treated wounds, the mean diameter was smaller and the wound closure rate was higher than in the control. Histological study revealed that PRP treated wounds showed more granulation formation and angiogenesis on day 7, and faster epithelialization, more granulation formation and collagen deposition were observed on day 14 than in control wounds. On day 21, collagen deposition and epithelialization were enhanced in PRP treated groups. Overall, PRP application showed beneficial effects in wound healing, and intralesional injection was useful for application of PRP and could be a good therapeutic option for wound management in dogs.
Animals ; Collagen/metabolism ; Dermis/cytology/injuries/physiology ; Dogs ; Epidermis/cytology/injuries/*physiology ; Female ; Granulation Tissue/cytology ; Injections, Intralesional/veterinary ; Male ; Neovascularization, Physiologic ; *Platelet-Rich Plasma ; Regeneration ; Treatment Outcome ; *Wound Healing ; Wounds and Injuries/therapy/*veterinary