Canine cutaneous mast cell tumours (MCTs) have a variable biologic behaviour, and accurate staging is necessary to dictate therapy and predict outcome. Regional lymph node (RLN) involvement is a relevant prognostic factor. While obvious lymph node (LN) metastases are relatively easy to be diagnosed, micrometastatic disease recognition is challenging. The main aim of the study was to evaluate the number of mast cells (MCs) in the LNs of clinically healthy dogs (n = 4, group 1), dogs with inflammatory diseases (n = 31, group 2) and dogs with cutaneous MCT (n = 27, group 3), including animals with no RLN metastases (subgroup 3.1), those with occasional MCs in RLNs (3.2) and those with obvious RLN metastasis (3.3). MCs also were morphometrically evaluated for the following nuclear parameters: mean nuclear area (MNA), mean nuclear perimeter (MNP), largest to smallest diameter length (LS ratio), mean nuclear form factor and coefficient of variation of nuclear area. The average percentages of MCs were 0.0 and 0.01 in groups 1 and 2, respectively, and 0.07, 2.4 and 47.1 in subgroup 3.1, 3.2 and 3.3. MNA and MNP were significantly higher in subgroup 3.3 than in group 2 (P < 0.05). MNA and MNP in subgroup 3.2 suggested the presence of neoplastic MCs; this prediction of micrometastatic load correlated with outcome. Analysis of preliminary results shows that nuclear morphometry is useful to detect micrometastatic disease in RLN of dogs bearing cutaneous MCTs.

During the last few years, reports have appeared claiming that lufenuron diminished or even cured dermatophyte infections in cats and dogs. As these observations have a rather anecdotal character leading to some ambiguity in the literature, it was decided to test lufenuron in a generally accepted animal model for dermatomycotic infection. The test was carried out in guinea pigs artificially infected with Microsporum canis on scarified dorsal skin and orally treated with lufenuron (Programä). The efficacy of up to five doses of 80 mg/kg was assessed 7 and 14 days after the start of treatment. All animals failed to show any improvement in skin lesions as compared to the vehicle-only treated animals. Clinical symptoms taken into account were scaling, crust formation, erythema, and exudation. Neither the number of treatments (one or five) nor the dose range (40 or 80 mg/ kg) made any difference. Itraconazole, tested earlier under identical circumstances, resulted in a clear and consistent improvement at day 7 of the infection at a dose of 15 mg/kg, given either in one dose or spread over several days. The absence of antimycotic activity of lufenuron in this established animal model constitutes a significant element in the discussion on the antifungal potency of lufenuron and supports the fact that there is, as yet, no evidence that benzoylphenyl urea derivative compounds have an effect on chitin synthesis in fungi.

Acceleration of wound healing and improvement of scarring at skin graft donor sites and trauma or surgical lesions are important clinical goals in human and veterinary medicine. It has been discovered that wounds made on early mouse embryos heal quickly and perfectly, with no scars. The cellular and molecular differences between scarfree embryonic healing and scar-forming adult healing have been investigated. As a result, molecules have been identified which can be experimentally manipulated during adult healing, both to accelerate the process and to improve scarring. Some of these molecules represent pharmaceutical targets to which novel therapeutic agents have been developed. For example, embryonic wounds have high levels of TGFb3 from endogenous keratinocytes and fibroblasts, but relatively low levels of TGFb1 and TGFb2 derived from degranulating platelets and inflammatory cells, by comparison to adult wounds. Therapeutically elevating the level of TGFb3 allows adult rodent and porcine wounds to heal significantly faster and with improved scarring. These experimental findings have progressed into further studies in humans. A number of clinical trials with novel pharmaceuticals designed to accelerate healing and prevent scarring have been successfully completed, and further large patient-based trials are ongoing. These studies indicate that pharmaceutical treatment of healing wounds to accelerate the process (e.g. accelerated re-epithelialization of graft sites) or improve scarring may soon supplement the current surgical and device approaches to wound management.Assessment of re-epithelialization is commonly used to evaluate rates of cutaneous wound healing in experimental studies with treated and control wounds; results may be expressed as percentage of re-epithelialization over the wound surface. This is difficult with crusted lesions where wound margins are obscured. However, even when measured histologically, this approach does not allow accurate assessment of dermal repair. This study aimed to evaluate and compare the use of clinical assessment, high-resolution ultrasound (HRU) and histological morphometry in assessment of mode and rate of healing in open wounds of canine skin. The dorsal thoracolumbar area of 10 beagle dogs was clipped and two rows of six full-thickness cylinders of skin removed (5-mm punch biopsies) on either side of the midline under general anaesthesia. Wounds were allocated randomly on left and right sides to treatment or control groups and wound gel (active formulation or base) applied twice daily; wounds were allowed to form a scab and heal by second intention. Concentric 8-mm punch biopsy samples of the healing wounds were taken on days 1, 2, 4, 8 and 14 for histopathological assessment, leaving two wounds per dog to be followed by HRU throughout the study. Wounds were imaged longitudinally and transversely with 20 MHz HRU daily for 28 days using the wound gel as the transmission medium. Wound morphometry was performed on the digital HRU images (diameter at top, middle and bottom,...