Tumour, but not Age-associated, Increase of Senescence Markers γH2AX and p21 in the Canine Eye.

Senescent cells display an irreversible cell cycle arrest with resistance to apoptosis. They are known to accumulate with age in mice, monkeys and man, and are suspected to drive the development and progression of neoplasia. Eyes develop age-associated changes, most commonly in the retina, cornea and lens. The aim of this study was to test whether senescent cells increase with age in the canine eye in general and in the microenvironment of ocular tumours in particular. The senescence markers γH2AX and p21 were tested in young (n = 10, age ≤2 years) versus old (n = 9, age range 9.5-12.4 years) canine eyes, as well as in the microenvironment of intraocular tumours, namely uveal melanocytomas (n = 13) and ciliary body adenomas (n = 9). To consider a potential association of senescence with biological behaviour, we compared the expression of both markers in tumour cells of benign uveal melanocytomas (n = 13) versus malignant conjunctival melanomas (n = 7). Canine eyes showed no age-dependent changes in senescent cells. However, a significant increase of the percentage of γH2AX- or p21-labelled cells was found in the retina, uvea and lens of tumour-bearing eyes. Tumour cells in conjunctival melanomas had a significantly increased percentage of p21-expressing cells compared with uveal melanocytomas. We conclude, that senescent cells do not accumulate with age in otherwise normal canine eyes and that a senescent microenvironment of intraocular tumours is unlikely to be age driven. In addition, as in man, the percentage of p21-positive cells was increased in melanomas, supporting the theory that malignant tumours may override the senescence-associated cell cycle arrest.

Does prebiotic feeding affect equine gastric health? A study on the effects of prebiotic-induced gastric butyric acid production on mucosal integrity of the equine stomach.

Fructo-oligosaccharides are commonly administered as prebiotics to horses in order to reduce the risk of disruption of microbial populations in the hindgut. Their microbial degradation to SCFA already begins in the stomach potentially resulting in increased gastric concentrations of SCFA such as butyric acid. The impact of butyric acid on the squamous mucosa is postulated to be detrimental, its effects on the glandular mucosa are yet unknown. Thus, the aim of this study was to determine the effects of butyric acid exposure on the functional integrity and morphology of the equine nonglandular and glandular gastric mucosa using butyric acid concentrations equivalent to the ones found in horses subjected to prebiotic fructo-oligosaccharides feeding. Gastric mucosal samples of healthy horses were exposed to butyric acid using the in vitro Ussing chamber technique. Electrophysiological parameters were continuously monitored, mucosal samples were blinded and histomorphological analysis was performed using a scoring system for assessment of histopathologic changes. Exposure to butyric acid resulted in pathohistomorphological changes in the glandular mucosa and in impairment of functional mucosal integrity in the squamous and the glandular mucosa as documented by significant changes in tissue conductances (Gt). Administration of fructo-oligosaccharides as a preventive prebiotic measure to horses should therefore be carefully considered, particularly in horses known to be at risk of developing EGUS.

The role of Virus "X" (Tortoise Picornavirus) in kidney disease and shell weakness syndrome in European tortoise species determined by experimental infection.

Tortoise Picornavirus (ToPV) commonly known as Virus "X" was recently discovered in juvenile European tortoises suffering from soft carapace and plastron as well as kidney disease. Therefore, this virus was a potential candidate to be a causative agent for these disease patterns. Spur thighed tortoises (Testudo graeca) seemed to be more susceptible to establish clinical symptoms than other European species like T. hermanni. Thus this trial investigated the role of ToPV in the described syndrome. Two groups of juvenile European tortoises (T. graeca and T.hermanni) each of 10 animals, were cloacally, oronasally and intracoelomically inoculated with an infectious dose (~ 2000 TICD) of a ToPV strain isolated from a diseased T. graeca. A control group of two animals of each species received non-infected cell culture supernatant. The tortoises were examined daily and pharyngeal and cloacal swabs for detection of ToPV-RNA by RT-PCR were taken from each animal every six days for a period of 6 months. At the end of the study the remaining animals were euthanised and dissected. Bacteriological and parasitological tests were performed and organ samples of all tortoises were investigated by RT-PCR for the presence of ToPV and histopathology. Animals that were euthanised at the end of the experiment, were examined for presence of specific anti-ToPV antibodies. Several animals in both inoculated groups showed retarded growth and a light shell weakness, in comparison to the control animals. Three animals were euthanised during the trial, showing reduced weight gain, retarded growth, severe shell weakness and apathy, in parallel to clinical observations in naturally infected animals. In all inoculated animals of both species an intermittent virus shedding, starting from 18 days post inoculation (d.p.i.), till 164 d.p.i. was detected, while the control animals remained negative. The virus was successfully reisolated in terrapene heart cell culture in 16 of 20 inoculated animals of both species. Histopathology of most inoculated animals revealed a lack of bone remodeling and vacuolisation in kidney tubuli which supports the described pathogenesis of nephropathy and osteodystrophy. Anti- ToPV antibody titres ranged from 1:2 to >1:256 in 13 of 20 animals, whereas all control animals were seronegative. The study proofed the Henle Koch`s postulates of ToPV as causative agent for shell dystrophy and kidney disease in both testudo species. The proposed species specific sensitivity towards clinical disease was not observed.

[Calcitriol induced hypercalcemia in a hunting dog with a disseminated Paecilomyces variotii infection]. / Calcitriol-bedingte Hyperkalzämie bei einem Jagdhund mit disseminierter Paecilomyces variotii-Infektion.

INTRODUCTION: A 5-year old hunting dog was presented with reduced appetite, weight loss and polyuria/polydipsia. Hematology and clinical chemistry revealed anemia, leukocytosis, increased liver enzymes, hypoalbuminemia and hypercalcemia. The cytological, pathohistological and microbiological examination identified a disseminated infection with the saprophytic mould fungus Paecilomyces variotii in the biopsies of the spleen and a lymph node. Determination of vitamin D metabolites confirmed a calcitriol induced hypercalcemia.

Moxifloxacin is not anti-inflammatory in experimental pneumococcal pneumonia.

OBJECTIVES: Anti-inflammatory functions of antibiotics may counteract deleterious hyperinflammation in pneumonia. Moxifloxacin reportedly exhibits immunomodulatory properties, but experimental evidence in pneumonia is lacking. Therefore, we investigated moxifloxacin in comparison with ampicillin regarding pneumonia-associated pulmonary and systemic inflammation and lung injury. METHODS: Ex vivo infected human lung tissue and mice with pneumococcal pneumonia were examined regarding local inflammatory response and bacterial growth. In vivo, clinical course of the disease, leucocyte dynamics, pulmonary vascular permeability, lung pathology and systemic inflammation were investigated. In addition, transcellular electrical resistance of thrombin-stimulated endothelial cell monolayers was quantified. RESULTS: Moxifloxacin reduced cytokine production in TNF-α-stimulated, but not in pneumococci-infected, human lung tissue. In vivo, moxifloxacin treatment resulted in reduced bacterial load as compared with ampicillin, whereas inflammatory parameters and lung pathology were not different. Moxifloxacin-treated mice developed less pulmonary vascular permeability during pneumonia, but neither combination therapy with moxifloxacin and ampicillin in vivo nor examination of endothelial monolayer integrity in vitro supported direct barrier-stabilizing effects of moxifloxacin. CONCLUSIONS: The current experimental data do not support the hypothesis that moxifloxacin exhibits potent anti-inflammatory properties in pneumococcal pneumonia.

Prevalence of biofilms on surgical suture segments in wounds of dogs, cats, and horses.

The formation of biofilms on surgical implants is thought to play a major role in chronic infection and wound-healing disorders and has been rarely described in veterinary medicine. Due to poor and unreliable results from bacterial culturing, histology may be an economic tool for the detection of biofilms. In this study, the prevalence of biofilms on surgical suture materials and swabs with chronic wound-healing complications in dogs, cats, and horses was assessed by histologic examination using hematoxylin and eosin, Gram, and Giemsa stains, as well as periodic acid-Schiff reaction. Of the 91 tissue samples with intralesional suture material or swab residues associated with inflammation, only 2 contained bacterial colonies arranged in an extracellular polymeric matrix consistent with a biofilm. The results of this study suggest that biofilms on suture material may occur in veterinary medicine.

[Equine leukaemic lymphoma--a rare form of equine lymphoma]. / Das equine leukämische Lymphom--eine seltene Unterart des equinen Lymphoms.

Equine leukaemic lymphoma is a rare disease of the haematopoetic tissue. It results from neoplastic degradation of B- and T-lymphocytes and their occurrence in the blood. Clinical signs are often unspecific and include chronic weight loss, ventral oedema at the thorax and abdomen and regional lymphadenopathy. Horses are often presented late in the course of the disease and therapy is rarely successful. This review summarizes the clinical pathologic findings of equine leukaemic lymphoma and the findings of laboratory testing and other diagnostic measures, and presents treatment options described in the literature.

[Disturbances of water metabolism in two dogs and one cat with central nervous system disorders]. / Störungen des Wasserhaushaltes bei zwei Hunden und einer Katze mit ZNS-Erkrankungen.

Hypernatremia due to different pathophysiological mechanisms results in a rise in plasma osmolality. Dependent on its severity and on the speed of its development hyperosmolality can be life-threatening. This article describes 2 dogs and 1 cat with central nervous system disorders (adenoma of the pituitary gland, cerebral trauma). All patients developed normovolemic hypernatremia due to pituitary gland and hypothalamus dysfunction, respectively. Plasma sodium concentrations ranged from 163 to 185 mmol/l. Neurological examinations revealed lethargy, disturbances of consciousness, and ataxia, respectively. The dogs had to be euthanased due to the grave prognosis, the cat with cerebral trauma survived.

Le développement d'une hypenatrémie peut avoir plusieurs mécanismes patho-physiologiques. Dans ces cas, il se produit toujours une élévation de l'osmolarité du plasma. Selon l'importance de l'hypernatrémie et la vitesse de l'apparition, une hyperosmolarité peut mettre la vie en danger. Dans le présent article, on décrit des affections du système nerveux central chez deux chiens (adénome de l'hypophyse) et un chat (trauma crânien) ayant développé une hypernatrémie normovolémique suite à un dysfonctionnement de l'hypophyse ou de l'hypothalamus. Les concentrations plasmatiques de sodium étaient comprises entre 163 et 185 mmol/l. Les animaux présentaient de la léthargie, des troubles de la conscience et de l'ataxie. Vu le mauvais pronostic, les chiens ont dû être euthanasiés, le chat victime d'un traumatisme crânien a survécu.

Diagnostic value of morphometry in feline hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is the most common form of feline heart disease. To date, reliable morphometric reference data for anatomical or histological changes are unavailable. The aim of this study was to identify diagnostically relevant morphometric criteria that clearly distinguish feline HCM from normal hearts. Hearts from 15 cats with HCM had increased weights (g per distance between the first and eighth vertebral bodies) when compared with hearts from 15 matched control cats. Several anatomically defined and digitally scanned areas of standardized cross sections were significantly increased in HCM when compared with controls, including the area across the entire heart half-way between the coronary sulcus and apex, the right and left ventricular walls and the ventricular septum. Differences were similar when the papillary muscles were included in the measurements of the right and left ventricular walls and the ventricular septum. Histological morphometric analyses failed to identify any significant differences, including the diameter and cross-sectional area of cardiomyocytes and the length, width or areas of cross-sectioned nuclei. In addition, morphometric analyses failed to identify any differences in the amount of cardiomyocyte fibre branching or myocardial fibrosis. Thus, only the relative weight and macroscopical analyses proved useful in distinguishing feline hearts with HCM from normal hearts. The results do not uphold the hypothesis that increased cardiomyocyte diameter is a principal change in feline HCM.

Does the taking of biopsies affect the metastatic potential of tumours? A systematic review of reports on veterinary and human cases and animal models.

Clinicians and pathologists are sporadically asked by owners whether the taking of tumour biopsies may affect the behaviour of the tumour, including its potential to metastasise. Unfortunately, systematic studies on this subject are unavailable in veterinary medicine, and the aim of this study was to estimate the risk of adverse effects of biopsy taking on tumour progression in animals. A systematic review of veterinary and human case reports and clinical studies as well as experimental animal models of biopsy-induced tumour metastasis was undertaken. There were only two veterinary case reports of needle tract metastases (NTM) following the taking of needle biopsies from urogenital and pulmonary tumours. Seventeen experimental studies found a high incidence of NTM but only a rat osteosarcoma and a hamster squamous carcinoma model showed an increased incidence of distant or regional metastases after incision or excision biopsy. In human medicine, the occurrence of NTM has been reported after the taking of biopsies from mesotheliomas (15%), melanomas (11%) and gall bladder tumours (11%), liver metastases of colon carcinomas (4%) and mammary carcinomas (4%) but an incidence of only <1% for all other tumours. Circulating tumour cells increased immediately after the taking of biopsies from human squamous cell, prostate, breast and hepatocellular carcinomas. Although no increased risk of biopsy-induced distant metastasis has been reported for any type of tumour, this is inconclusive due to a lack of non-biopsied control groups in human studies. Reports of biopsy-induced metastasis in animal tumours indicate that the taking of transcutaneous biopsies from urogenital tumours may be associated with a risk of NTM. However, there is no evidence of a general increase in risk of distant metastases in any tumour type in people or animals. The overall risk therefore appears to be negligible when compared to the valuable information obtained from biopsies in veterinary practice.

Peliosis hepatis in cats is not associated with Bartonella henselae infections.

Peliosis hepatis is a vasculoproliferative disorder of the liver with infectious and noninfectious causes. In humans and dogs, Bartonella henselae has been linked to peliosis hepatis. Although domestic cats are the natural reservoir of B. henselae and although peliosis hepatis is common in this species, an association between this condition and infection with B. henselae has never been investigated in cats. In this study, 26 cases of peliosis hepatis in cats were tested for B. henselae infection by nested polymerase chain reaction and immunohistochemistry. The authors failed to detect B. henselae nucleic acid or antigen in any of the affected liver specimens. These findings suggest that, unlike in humans and dogs, peliosis hepatis in cats may not be significantly associated with a B. henselae infection.

Multiple cystic intestinal duplications in a cat.

A 7-year-old, female European shorthair cat with a history of recurrent vomiting had a 2-cm cystic mass in the midjejunum. Cross-sectioning and histology revealed 3 separate cystic structures in the muscular layer, in addition to a regularly structured intestinal lumen. One cyst had a 3-layered wall consisting of a dysplastic mucosa, a regularly structured submucosa, and partly double-layered muscularis that sporadically contained neurons resembling a myenteric plexus. The remaining 2 cysts had similar structures except for granulation tissue lining the lumen. The lesion was diagnosed as multiple cystic duplications in the midjejunum, which is unknown to the veterinary literature to date.

The mouse is not permissive for equine herpesvirus 2 (EHV-2), however viral DNA persisted in lung and spleen depending on the inoculation route.

BALB/c mice were inoculated with 3 EHV-2 low passage isolates. After intranasal inoculation, viral DNA was detected by virus-specific nested PCR in the lung up to day 30 post inoculation and in nasal turbinates till day 7. In trigeminal ganglia, olfactory bulb, brain and lymph nodes viral DNA was randomly shown by PCR. After intraperitoneal inoculation viral DNA was present in lymphoid tissues. The spleen was PCR positive up to day 30 and showed a splenomegaly. Clinical signs, virus replication and viraemia, were not observed and no virus strain-specific differences were obvious. Control mice inoculated with equine herpesvirus 4 were PCR negative in all tissues.

Detection of equine herpesvirus type 2 (EHV-2) in horses with keratoconjunctivitis.

The prevalence of EHV-2 in 27 horses with keratoconjunctivitis and 21 clinically healthy horses of different ages and stocks were analyzed. We demonstrated that EHV-2 was present in 12 keratoconjunctivitis cases as shown by nested PCR on ocular swabs. This is statistically more often than in the control group, where only two ocular swabs were EHV-2 positive. Cocultivation was successful on peripheral blood leukocytes of healthy and diseased horses but not on swabs. We isolated ten EHV-2 strains from diseased and nine from control horses, whereas 16 isolates showed different restriction enzyme patterns. The results of immunfluorescence and neutralization tests are predictory only in combination with the nested PCR data on ocular swabs. A successful antiviral treatment in nine out of 16 cases supports the aetiological role of EHV-2 in this ocular disease.