Hilde De Cock

Enzyme Activity and Immunohistochemical Localization of Dipeptidyl Peptidase 8 and 9 in Male Reproductive Tissues

The mRNA expression pattern of dipeptidyl peptidase (DPP) 8 and DPP9, two DPP4 homologs, was studied previously and showed a broad tissue distribution. In this study, protein expression and activity of DPP8 and DPP9 were investigated in male reproductive tissues of different mammals. Based on specific DPP activities and inhibition profiles, the proline-selective DPP activity in the bovine and rat testis could predominantly be attributed to DPP8/9 and not to DPP4. This is in contrast to the epididymis, where most of the activity was caused by DPP4. Bovine sperm preparations had very low or undetectable DPP8/9 activity. After characterization of polyclonal antibodies specific for DPP8 or DPP9, we could localize both enzymes in seminiferous tubules of the testis. A specific staining for DPP9 was found associated with spermatozoids embedded in the epithelium, just before their release into the lumen, and in spermatids. DPP8 was localized in spermatozoids in an earlier stage of maturation. These findings help to provide insight into the physiological role of DPP4-like enzymes in the male reproductive system. This manuscript contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.

Bovine papillomavirus DNA can be detected in keratinocytes of equine sarcoid tumors

Bovine papillomavirus (BPV)-1 and -2 is linked to equine sarcoids, a commonly observed skin tumor in horses that is of considerable veterinary importance. Previous studies using in situ hybridization have detected BPV DNA only in fibroblasts and not in keratinocytes of sarcoids. In contrast, normal equine skin latently infected with BPV shows a dysplastic epithelium without dermal changes, similar to lesions induced by other papillomavirus types infecting the epithelium. The first goal of our study was to describe the epidermal and dermal characteristics of several stages in sarcoid development. Next, we explored whether BPV can infect epidermal cells in the horse using real-time PCR on laser-micro-dissected keratinocytes and fibroblasts. We found that latently infected normal skin samples and a subset of early stage sarcoids show dysplastic, koilocyte-like epithelial changes. BPV DNA was detected in keratinocytes in 40% of the samples with these particular epithelial properties, whereas advanced sarcoids only had BPV DNA in the fibroblasts. These data may indicate a novel and intriguing pathway of BPV infection in the horse composed of a first step of keratinocyte infection, followed by migration of viral material towards the dermis resulting in infection of sub-epidermal fibroblasts and their fully transformed phenotype. Additionally, an example of co-existence of a dermal BPV-1 and an epidermal BPV-2 infection in the same lesion is shown, indicating that horses can harbor infection with more than one BPV type at the same time.

Magnetic resonance and computed tomography imaging of a carotid body tumor in a dog

A 5-year-old castrated male Labrador Retriever was presented to a referring veterinarian for a swelling in the neck region. Based on the results of histopathology, a carotid body tumor, was diagnosed. The dog was referred to a medical imaging unit for further staging and follow up. This report describes the magnetic resonance (MR) and computed tomographic (CT) appearance of a carotid body tumor.

Cutaneous adverse drug reaction in a dog associated with imepitoin

BACKGROUND The macroscopic appearance of cutaneous adverse drug reactions can be similar to a plethora of skin diseases and in particular may resemble autoimmune and immune-mediated disorders. The reaction can occur after single or multiple administrations, with the latter varying in durations of up to years of treatment. These reactions are mostly self-limiting with cessation of the offending drug. OBJECTIVES To report a cutaneous adverse drug reaction associated with chronic administration of imepitoin. CASE REPORT A 4-year-old, Jack Russell terrier dog was presented with progressive skin lesions of 1-week duration. The dog had a 6 month history of idiopathic epilepsy treated with imepitoin for the previous 5 months. Imepitoin is an anti-epileptic drug that acts as a low-affinity partial agonist of the benzodiazepine site at the GABAA receptor. The dosage of imepitoin was increased from 20 mg/kg twice daily to 30 mg/kg twice daily, 3 days before the onset of skin lesions, due to uncontrolled seizures. [Correction added on 15 February 2016 after first online publication: In the preceding sentence, the dosage of imepitoin was previously incorrect and has been amended in this current version.] Dermatological examination revealed erythema and exfoliation at the mucocutaneous junctions of the lips, lip folds, philtrum, ears, axillae and the ventral abdomen. Small erosions and depigmentation were visible on the oral mucosa, lip folds and philtrum. Histopathology was supportive of a lupoid drug reaction. Complete resolution of skin lesions was seen after discontinuation of imepitoin and low dose of prednisolone during a period of 4 weeks. No recrudescence of skin lesions was observed during a 6 month follow-up period. CONCLUSION AND CLINICAL IMPORTANCE Imepitoin may result in cutaneous adverse drug reactions in dogs.

Inflammatory bowel disease (IBD) in horses: a retrospective study exploring the value of different diagnostic approaches

BackgroundDiagnosing IBD in horses is challenging and requires a multimodal approach, since no conclusive diagnostic test is available.The objectives of this study were to provide an overview of population characteristics, results of applied diagnostic tests, treatment modalities and outcome in a large group of horses thought to have IBD and that were presented to four large equine referral hospitals, and to provide an exploratory investigation of possible associations between results of applied diagnostic tests, applied treatment modalities and outcome.A retrospective case series was performed across four large equine referral hospitals. Seventy-eight horses, thought to have IBD were included. Case history, clinical findings, diagnostic test results including oral glucose tolerance test (OGTT) and enteral biopsies (both duodenal and rectal), applied therapy and outcome were studied. A Chi-Square test was used to identify associations between results of diagnostic tests, treatment and outcome. P-values < 0.05 were considered significant.ResultsLethargy, diarrhoea, recurrent colic and weight loss were recorded in respectively 21,8%; 14,1%; 28,2% and 78,2% of cases. Over 70% of horses thought to have IBD had an abnormal OGTT. Only weight loss was significantly associated with aberrant enteral biopsy results, but not with abnormal OGTT results or low blood total protein. There was no association between an aberrant biopsy result and a disturbed OGTT. There was no association between either OGTT results or enteral biopsy results and a low blood total protein content, presence of gastric ulcer disease or an aberrant endoscopic aspect of the duodenal entrance.ConclusionsWeight loss is a highly prevalent symptom in IBD suspected horses. Enteral biopsies may be a useful diagnostic aid in the work-up of horses thought to suffer from IBD, however further research is required to demonstrate their true diagnostic value. Until more standardized scientific research is available, one should be careful with the interpretation of enteral biopsy results There is a need for better standardization of enteral biopsy procedures and the histopathological scoring of biopsies.

Atypical canine recurrent alopecia

different dogs. We would like to report the development of an opensource software platform to analyse the punctiform topographical distribution of canine nodular cutaneous lesions directly connected with a database that contains clinical, anamnestic, histopathological, therapeutic and other useful information. A specific relational Web database for collection of the characteristics and location of each lesion was created using open-source software, including the operating system (Linux Ubuntu 10.10) MySQL AB version 5.1. A relational database management system was used to create the database, and a user-friendly graphical interface was obtained from the Apache HTTP Server version 2.2 and Symfony version 1.2.4 (Web application framework written in PHP). A Web GIS platform was integrated into the Web database to allow the registration of topographical data. Nodular skin lesions (n = 387) from 350 dogs were retrieved from the Histopathology Diagnostic Service of the Department of Food Science, University of Udine (Italy). A complete dermatological description was obtained using a multiple-choice format questionnaire to standardize data collection. The accurate identification of the topographical location of each lesion was performed by the clinicians by indicating the lesion on a paper map drawn of canine mesomorphic breeds. The cutaneous location of the lesion was inserted into the Web GIS system with a GeoTIFF image corresponding to the same model. The distribution pattern was analysed by two spatial statistical methods, i.e. average nearest neighbour and kernel density function. The results of the nearest neighbour analysis showed a clustering pattern of sites of onset of lesions examined by query. In particular, the clustering was evident for the following categories of nodular lesion: neoplastic (corrected Z-value, 12.04; P-value <0.001); benign neoplastic (corrected Z-value, 4.81; P-value <0.001); malignant neoplastic (corrected Z-value, 4.77; P-value <0.001); and inflammatory lesions (corrected Z-value, 3.1; P-value <0.01; Figure 1). Through the kernel density estimation, it was possible to prepare topographical maps with remarkable clarity. The maps were easy to interpret, and they showed that the highest relative density of all nodular lesions (n = 387) was concentrated on the front part of the animal and in the scrotal region. The distribution of benign neoplasms (n = 138) showed maximal values of relative density on the dorsal portion of the skull. Malignant neoplastic nodular lesions (n = 139) showed maximal values of relative density in the topographical area of the chest, the scrotum and the posterior surface of the thigh. Inflammatory nodular lesions (n = 32) showed a strong clustering on the dorsal surfaces of the metacarpal–phalangeal region and rostral portion of the dorsal nasal region. The GIS method used in this study has shown interesting findings. In particular, the use of a GIS system in mapping lesions could be considered as a new approach for collection of clinical data from skin lesions. The creation of density maps of the relative frequency of nodular skin lesions could be useful for helping veterinary clinicians to have a general idea about the possible differential diagnoses when presented with such lesions. This technique could be a valuable aid for training, for didactic purposes and for researchers. Furthermore, it allows statistical analysis of nodular skin diseases, including, for example, factors such as their anatomical distribution, breed association and disease incidence.