Evaluation of papillomaviruses associated with cyclosporine-induced hyperplastic verrucous lesions in dogs

OBJECTIVE: To determine whether cyclosporine A-induced hyperplastic skin lesions of dogs were associated with papillomavirus infections. ANIMALS: 9 dogs that were treated with cyclosporine A and developed hyperplastic skin lesions. PROCEDURE: History and clinical and histopathologic data were collected. Paraffin-embedded skin biopsy specimens from hyperplastic skin lesions were immunostained for common papillomavirus genus-specific structural antigens by use of a polyclonal rabbit anti-bovine papillomavirus type 1 antiserum. Sections from each tissue block underwent DNA extraction, and polymerase chain reaction (PCR) assays were performed with several sets of primers to amplify a wide range of papillomavirus DNA from humans and other animals. RESULTS: In 7 of 9 dogs, there were more than 10 hyperplastic skin lesions that microscopically resembled those of psoriasiform lichenoid dermatosis. In those dogs, results of testing for papillomavirus via immunohistochemical analyses and PCR assays were negative. In the other 2 dogs, there were only 1 and 3 verrucous lesions, and in those dogs, histologic evaluation revealed koilocytes and nuclear viral inclusions that were immunoreactive for papillomavirus antigens. Papillomavirus DNA was amplified from both dogs. One of the sequences was characteristic for the canine oral papillomavirus, whereas the other had similarities with the recently described canine papillomavirus 2. CONCLUSIONS AND CLINICAL RELEVANCE: In dogs, hyperplastic skin lesions occasionally develop during treatment with cyclosporine A. Most of the lesions resemble those of psoriasiform lichenoid dermatosis, although papillomavirus can be detected in some instances.     

Effects of Interferon‐Tau and Steroids on Cytochrome P450 Activity in Bovine Endometrial Epithelial Cells

The objective of the current study was to examine cyclooxygenase (COX), cytochrome P450 1A (CYP1A) and 2C (CYP2C) activity in bovine endometrial cell cultures following exposure to oxytocin (OT), interferon‐τ (IFN), estradiol (E2) and/or progesterone (P4). Bovine endometrial epithelial cells were treated with OT, IFN, a combination of OT+IFN or control (CON) media for 24 h. For the second experiment, cells were treated with E2, P4, a combination of E2 + P4 or CON media for 24 h. Treatments were performed in triplicate, and the experiment was repeated four times (n = 12 per treatment). Treatment with OT alone increased (p < 0.01) activity of COX compared with CON; however, OT alone did not alter activity of CYP1A (p = 0.55) or CYP2C (p = 0.46) compared with CON. Activity of CYP1A and CYP2C was decreased in cells exposed to IFN (p < 0.01) or OT+IFN (p < 0.01) compared with CON. Treatment with E2 alone did not alter activity of CYP1A (p = 0.64) or CYP2C (p = 0.06) compared with CON. Activity of CYP1A and CYP2C was decreased (p < 0.01) in P4 vs CON. In summary, IFN exposure, irrespective of OT treatment, decreased the activity of CYP1A and CYP2C. Activity of CYP1A was decreased following P4 treatment alone, while that of CYP2C was decreased following both P4 and E2 + P4 treatment. The mixed function monooxygenase enzymes, CYP1A and CYP2C, have been implicated in synthesizing embryotoxic compounds; therefore, downregulation in the endometrium may be necessary during maternal recognition of pregnancy.     

Bovine ileal dome lymphoepithelial cells: endocytosis and transport of Brucella abortus strain 19

Ligated ileal loops of calves were inoculated with Brucella abortus and examined at 2, 4, 6, 10, and 24 hours post-inoculation. B. abortus was identified by light and electron microscopy using immunoperoxidase and antibody-coated colloidal gold techniques. B. abortus was detected in vesicles, phagolysosomes, and large vacuoles of lymphoepithelial cells. Numbers of intracellular bacteria decreased with time after inoculation. B. abortus was also seen between and below lymphoepithelial cells and free in the dome interstitium and intestinal lymph vessels. Neutrophils and macrophages in both epithelium and lamina propria contained intact or degraded bacteria within phagosomes, phagolysosomes, and multivesicular bodies. These studies showed that (1) transepithelial migration of B. abortus occurred principally by dome lymphoepithelial cell endocytosis and transport, and (2) B. abortus was degraded by macrophages and neutrophils of the gut-associated lymphoid tissue.     

Comparison of Oral Prednisone and Prednisone Combined with Metronidazole for Induction Therapy of Canine Inflammatory Bowel Disease: A Randomized‐Controlled Trial

Background: Although prednisone and metronidazole are commonly used to treat canine inflammatory bowel disease (IBD), no randomized‐controlled trials have been performed. Hypothesis: Combination drug therapy with prednisone and metronidazole will be more effective than prednisone alone for treatment of canine IBD. Reduction in disease severity will be accompanied by decreased canine IBD activity index (CIBDAI) scores and serum C‐reactive protein (CRP) concentrations. Animals: Fifty‐four pet dogs diagnosed with IBD of varying severity. Methods: Dogs were randomized to receive oral prednisone (1 mg/kg; n = 25) or prednisone and metronidazole (10 mg/kg; n = 29) twice daily for 21 days. Clinical (CIBDAI) scores and serum CRP were determined at diagnosis and after 21 days of drug therapy. The primary efficacy measure was remission at 21 days, defined as a 75% or greater reduction in baseline CIBDAI score. Results: Differences between treatments in the rate of remission (both exceeding 80%) or the magnitude of its change over time were not observed. CRP concentrations in prednisone‐treated dogs were increased because of many dogs having active disease. Both treatments reduced CRP in comparison with pretreatment concentrations. An interaction between CIBDAI and CRP was identified in 42 of 54 dogs (78%), whereas 8 of 54 dogs (15%) showed disagreement between these indices. Conclusions and Clinical Importance: Prednisone is as effective as combined treatment with prednisone and metronidazole for induction therapy of canine IBD. CRP may be normal or increased in dogs with IBD and may be useful in assessing the response of individual dogs to treatment along with changes in the CIBDAI.     

Die Stickstoffdüngung noch besser auf das von Jahr zu Jahr Schwankende natürliche N-Angebot aus dem N-Pool des Bodens abstimmen

Es wird eine Methode dargestellt, die auf der Grundlage der Höhe der Wärmesumme eine differenzierte Möglichkeit der N-Düngung ableitet. In Abhängigkeit von der Wärmesumme und der Bodenfeuchte ergibt sich eine differenzierte N-Düngerbereitstellung aus dem Boden. Diese N-Mineralisation aus dem Bodenstickstoff ist bei der Bemessung einer zweiten Gabe zu berücksichtigen. Die ermittelte N_min-Menge entscheidet über die Notwendigkeit einer Nachdüngung im Sechs- bis Achtblattstadium des Maises. Für ein hohes Ertragspotential von 120 dt/ha Körnermais (86% TS) sollte ein N_min-Wert um 220 kg bei einer Wärmesumme von 310°C ausgewiesen werden. Bei diesen Zahlen ist keine Nachdüngung erforderlich.     

Minerals controlling arsenic distribution in floodplain soils

As a consequence of intensive mining of the western Erzgebirge since medieval times, floodplain soils of the Mulde river contain large concentrations of arsenic (As) (>50 mg kg⁻¹). Arsenic in soil is often bound to poorly crystalline Fe and Mn (hydr)oxides, which may dissolve under reducing conditions. Part of the As may also exist in primary minerals, predominately sulphides, or in secondary minerals formed upon weathering. In order to better understand the impact of seasonal flooding, we surveyed As‐bearing mineral phases, especially of iron (Fe) (hydr)oxides. Because Fe (hydr)oxides are clay‐sized, soil samples were fractionated into six particle‐size fractions. The fractions were digested with aqua regia for determination of total element concentrations, extracted with hydroxylammonium chloride (NH₃OHCl; selective for Mn (hydr)oxides and NH₄ oxalate), and analysed by X‐ray diffraction and scanning electron microscopy. The largely similar distribution of As and lead (Pb) suggested the potential co‐existence of the two elements in primary or secondary mineral phases. However, neither As–Pb minerals nor any other As mineral were detected. Association with Mn oxides was negligible. The predominant As‐bearing phases were poorly crystalline Fe (hydr)oxides, which also incorporated large amounts of Pb and were affected by redox dynamics.     

Pro and contra IBR-eradication

Bovine herpesvirus type 1 (BoHV-1) is the causative agent of respiratory and genital tract infections such as infectious rhinotracheitis (IBR), infectious pustular vulvovaginitis (IPV, balanoposthitis (IBP), and abortion. Despite of a pronounced immune response, the virus is never eliminated from an infected host but establishes life-long latency and may be reactivated at intervals. Europe has a long history of fighting against BoHV-1 infections, yet, only a small number of countries has achieved IBR-eradication. Therefore, it seemed appropriate to review the reasoning pro and contra such a task. Clearly, the goal can indeed be achieved as has been demonstrated by a number of European countries. However, detection and stamping out of seemingly healthy virus carriers is inevitable in the process. Unfortunately, the use of vaccines is only of temporary and limited value. Therefore, there are numerous considerations to be put forward against such plans, including the high costs, the great risks, and the unsatisfactory quality of tools. If either control or eradication of IBR is nonetheless a goal, then better vaccines are needed as well as better companion tests. Moreover, better tools for the characterization of viral isolates are required. Collaborative actions to gather viral strains from as many countries as possible for inclusion into a newly created clustering library would be most advantageous.     

Antimicrobial peptides and surfactant proteins in ruminant respiratory tract disease

In ruminants, respiratory disease is multifactorial and a leading cause of morbidity and mortality. Pulmonary innate immunity is the first line of defense for the respiratory tract. Alteration of regulation, expression, and function of these factors may be important to disease development and resolution. Many antimicrobial peptides and surfactant proteins are constitutively expressed in the respiratory tract and expression levels are regulated. Beta-defensins are cationic peptides with broad antimicrobial activity against bacterial, viral and fungal pathogens. Beta-defensins are primarily expressed in mucosal epithelia (and in some species leukocytes); where they may also participate in chemotaxis, wound repair and adaptive immune responses. Surfactant proteins A and D are secreted pulmonary surfactant proteins that have antimicrobial and immune regulatory activity. Anionic peptide is a constitutively expressed, aspartate-rich peptide that has antimicrobial activity and is most prominent during reparative epithelial hyperplasia. Regulation of these immune defense components by stress, pathogens, and inflammatory cytokines may play a role in the susceptibility to, severity and resolution of respiratory infection. The expression patterns of these molecules can be specific for host-species, class of pathogen and stage of infection. Understanding the regulation of antimicrobial peptide/protein expression will further enhance the potential for novel prophylactic and therapeutic modalities to minimize the impact of respiratory disease.     

Detection of novel papillomaviruses in canine mucosal, cutaneous and in situ squamous cell carcinomas

Papillomavirus (PV) DNA is frequently uncovered in samples of human skin squamous cell carcinomas (SCC). However, the role of these viruses in the development of such cancers in canine species remains controversial. While approximately 100 human PVs are known, only one single canine oral PV (COPV) has been identified and studied extensively. Therefore, we applied a narrow-range polymerase chain reaction (PCR) suitable for the detection of classical canine and feline PVs, as well as a broad-range PCR, which has been used for the detection of various novel PVs in humans, in order to analyse 42 paraffin-embedded samples, representing three different forms of canine SCCs. Ten samples of skin tissues with various non-neoplastic conditions served as controls. While none of the negative controls reacted positively, PV DNA was discovered in 21% of the tested SCC samples. Interestingly, the classical COPV was amplified from only one sample, while the other positive cases were associated with a variety of thus far unknown PVs. This study suggests that a fraction of canine SCC is infected with PVs and that a genetic variety of canine PVs exists. Therefore, these results will facilitate the future study of the role of PVs in the development of canine skin cancers.