[show abstract][hide abstract] ABSTRACT: Functional magnetic resonance imaging (fMRI) is a technique able to localize neural activity in the brain by detecting associated changes in blood flow. It is an essential tool for studying human functional neuroanatomy including the auditory system. There are only a few studies, however, using fMRI to study canine brain functions. In the current study ten anesthetized dogs were scanned during auditory stimulation. Two functional sequences, each in combination with a suitable stimulation paradigm, were used in each subject. Sequence 1 provided periods of silence during which acoustic stimuli could be presented unmasked by scanner noise (sparse temporal sampling) whereas in sequence 2 the scanner noise was present throughout the entire session (continuous imaging). The results obtained with the two different functional sequences were compared.
This study shows that with the proper experimental setup it is possible to detect neural activity in the auditory system of dogs. In contrast to human fMRI studies the strongest activity was found in the subcortical parts of the auditory pathways. Especially sequence 1 showed a high reliability in detecting activated voxels in brain regions associated with the auditory system.
These results indicate that fMRI is applicable for studying the canine auditory system and could become an additional method for the clinical evaluation of the auditory function of dogs. Additionally, fMRI is an interesting technique for future studies concerned with canine functional neuroanatomy.
BMC Veterinary Research 10/2013; 9(1):210. · 1.86 Impact Factor
[show abstract][hide abstract] ABSTRACT: Mammalian juveniles undergo dramatic changes in body conformation during development. As one of the most common companion animals, the time line and trajectory of a dog's development and its body's re-proportioning is of particular scientific interest. Several ontogenetic studies have investigated the skeletal development in dogs, but none has paid heed to the scapula as a critical part of the mammalian forelimb. Its functional integration into the forelimb changed the correspondence between fore- and hindlimb segments and previous ontogenetic studies observed more similar growth patterns for functionally than serially homologous elements. In this study, the ontogenetic development of six Beagle siblings was monitored between 9 and 51 weeks of age to investigate their skeletal allometry and compare this with data from other lines, breeds and species.
Body mass increased exponentially with time; log linear increase was observed up to the age of 15 weeks. Compared with body mass, withers and pelvic height as well as the lengths of the trunk, scapula, brachium and antebrachium, femur and crus exhibited positive allometry. Trunk circumference and pes showed negative allometry in all, pelvis and manus in most dogs. Thus, the typical mammalian intralimb re-proportioning with the proximal limb elements exhibiting positive allometry and the very distal ones showing negative allometry was observed. Relative lengths of the antebrachium, femur and crus increased, while those of the distal elements decreased.
Beagles are fully-grown regarding body height but not body mass at about one year of age. Particular attention should be paid to feeding and physical exertion during the first 15 weeks when they grow more intensively. Compared with its siblings, a puppy's size at 9 weeks is a good indicator for its final size. Among siblings, growth duration may vary substantially and appears not to be related to the adult size. Within breeds, a longer time to physically mature is hypothesized for larger-bodied breeding lines. Similar to other mammals, the Beagle displayed nearly optimal intralimb proportions throughout development. Neither the forelimbs nor the hindlimbs conformed with the previously observed proximo-distal order of the limb segment's growth gradients. Potential factors responsible for variations in the ontogenetic allometry of mammals need further evaluation.
BMC Veterinary Research 10/2013; 9(1):203. · 1.86 Impact Factor
[show abstract][hide abstract] ABSTRACT: Research on equine cytokines is often performed by analyses of mRNA. For many equine cytokines an analysis on the actual protein level is limited by the availability of antibodies against the targeted cytokines. Generation of new antibodies is ongoing but time consuming. Thus, testing the reactivity of commercially available antibodies for cross-reactivity with equine cytokines is of particular interest. Fifteen monoclonal antibodies against IL-1β, IL-6, IL-8, IL-12, IL-18 and Granulocyte Macrophage Colony stimulating factor (GM-CSF) of different species were evaluated for reactivity with their corresponding equine cytokines. Dot Blot (DB) and Western Blot (WB) analyses were performed using recombinant equine cytokines as positive controls. Immunohistochemistry (IHC) was carried out on equine tissue and flow cytometry on equine PBMC as positive controls. As expected, three equine IL-1β antibodies detected equine IL-1β in DB, WB and IHC. For these, reactivity in IHC has not been described before. One of them was also found to be suitable for intracellular staining of equine PBMC and flow cytometric analysis. Two antibodies raised against ovine GM-CSF cross-reacted with equine GM-CSF in DB, WB and IHC. For these anti-GM-CSF mAbs this is the first experimental description of cross-reactivity with equine GM-CSF (one mAb was predicted to be cross-reactive in WB in the respective data sheet). The other clone additionally proved to be appropriate in flow cytometric analysis. Two mAbs targeting porcine IL-18 cross-reacted in IHC, but did not show specificity in the other applications. No reactivity was shown for the remaining five antibodies in DB, although cross-reactivity of two of the antibodies was described previously. The results obtained in this study can provide beneficial information for choosing of antibodies for immunological tests on equine cytokines.
Veterinary Immunology and Immunopathology 09/2013; · 1.88 Impact Factor
[show abstract][hide abstract] ABSTRACT: The revision of an hip prosthesis can have diffrent
reasons. One frequent cause, especialley after implantation
of a conventional cup, is the so called stress-shielding effect
which can lead to a migration or loosening. Patientspecific
hip cups can be used to counteract this. However,
individual hip cups are only implanted for the treatment of
great deformations or tumours because of the cost-intensive
manufacturing. Within this project a patient-specific hip
cup prosthesis has to be developed and manufactured. Besides
the numerical design by means of a coupling between
multi-body simulation (MBS) and finite element method
(FEM), an inovative concept for the production of patientindividual
hip prosthesis out of titanium sheets is introduced
in this study.
[show abstract][hide abstract] ABSTRACT: Objective-To quantify left ventricle (LV) volumes by use of 1-D, 2-D, and 3-D echocardiography versus MRI in dogs. Animals-10 healthy Beagles. Procedures-During anesthesia, each dog underwent an echocardiographic examination via the Teichholz method, performed on the basis of standard M-mode frames (1-D); the monoplane Simpson method of disk (via 2-D loops); real-time triplane echocardiography (RTTPE) with a 3-D probe; and real-time 3-D echocardiography with a 3-D probe. Afterward, cardiac MRI was performed. Values for the LV end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF) were compared between each echocardiographic method and the reference method (cardiac MRI). Results-No significant differences for EDV, ESV, and EF were detected between RTTPE and cardiac MRI. Excellent correlations (r = 0.97, 0.98, and 0.95 for EDV, ESV, and EF, respectively) were found between RTTPE and values for cardiac MRI. The other echocardiographic methods yielded values significantly different from cardiac MRI and results correlated less well with results of cardiac MRI for EDV, ESV, and EF. Use of the Teichholz method resulted in LV volume overestimation, whereas the Simpson method of disk and real-time 3-D echocardiography significantly underestimated LV volumes. Conclusions and Clinical Relevance-Use of RTTPE yielded excellent correlations and nonsignificant differences with cardiac MRI and is a suitable method for routine veterinary cardiac examination.
American Journal of Veterinary Research 09/2013; 74(9):1223-30. · 1.35 Impact Factor
[show abstract][hide abstract] ABSTRACT: Gold bead implantation/gold acupuncture is becoming increasingly used in veterinary medicine as a method of pain treatment in cases of osteoarthritic diseases. Part one of the overview dealing with the use of gold implants as a treatment of canine hip joint dysplasia (cHD) introduced the method of implanting gold in tissue and publications which investigated the subsequent effects of implantation. This article focuses on publications concerning the clinical effectiveness of gold implantation within the scope of pain therapy in cHD. Due to the study design, a classification using evidence-based levels (EbL) was carried out. Three double-blind, placebo-controlled randomised studies (EbL II) were considered together with three retrospective studies on own patients (EbL IV) and five case studies (EbL IV). While the case and retrospective studies reported impressive therapeutic success in treating cHD-incurred pain with gold implantation, a pain-reducing effect through gold implantation was only demonstrated in one of the three double-blind studies. The two remaining EbL II studies found no differences between the placebo-group and the group of dogs treated with gold implantation. In one of these two studies, kinematic and kinetic gait analyses were used for objective evaluation of the effects of the treatment. Thus, the only study that carried out an objective evaluation of the therapeutic result of gold implantation came to the conclusion that the method is ineffective. For a concluding assessment of gold implantation in the case of cHD, gait analysis studies investigating the effects of gold implantation in comparison to a standard treatment with nonsteroidal anti-inflammatory drugs are currently lacking.
[show abstract][hide abstract] ABSTRACT: Objective-To evaluate the accuracy and reproducibility of left ventricular (LV) volumetric and function variables determined via contrast-enhanced cardiac CT and cardiac MRI in healthy dogs. Animals-10 healthy Beagles. Procedures-Cardiac MRI and cardiac CT were performed in anesthetized Beagles; both examinations were conducted within a 2-hour period. Cardiac MRI was performed with a 3.0-T magnet, and contrast-enhanced cardiac CT was performed with a 64-row detector CT machine. Data sets were acquired during apnea with simultaneous ECG gating. Short-axis images were created to determine functional variables via the Simpson method. Results-Cardiac CT values for mean end-diastolic and end-systolic LV volumes had excellent correlation (r = 0.95) with cardiac MRI measurements, whereas LV stroke volume (r = 0.67) and LV ejection fraction (r = 0.75) had good correlations. The only variable that differed significantly between imaging modalities was end-diastolic LV volume. For each pair of values, Bland-Altman analysis revealed good limits of agreement. Conclusions and Clinical Relevance-The 3-D modalities cardiac CT and cardiac MRI were excellent techniques for use in assessing LV functional variables. Similar results were obtained for LV volume and function variables via both techniques. The major disadvantage of these modalities was the need to anesthetize the dogs for the examinations.
American Journal of Veterinary Research 07/2013; 74(7):990-998. · 1.35 Impact Factor
[show abstract][hide abstract] ABSTRACT: Alongside the intestinal border, dendritic cells (DCs) sample large amounts of endogenous and potentially pathogenic antigens followed by initiation of protective immune responses or induction of tolerance. Breakdown of oral tolerance towards commensal bacteria is suggested to be crucial for the development of both human and canine inflammatory bowel disease (IBD). The aim of this study was to investigate canine intestinal DCs in the steady state and in dogs with IBD using multicolour immunofluorescence. In the healthy gut, DC-like cells expressed MHC II, CD1a8.2 and CD11c, and, in lower amounts, CD11b, within lamina propria, Peyer's patches (PPs) and mesenteric lymph nodes (MLNs), whereas those expressing CD80 and CD86 were only present in PPs and MLNs. Occasionally, DC-like cells were in contact with the intestinal lumen through transepithelial projections. In canine IBD, CD1a8.2+, CD11b+ and CD11c+ DC-like cells were decreased within the stomach, duodenum and colon, whereas the colonic mucosa revealed elevation of CD86+ DC-like cells. The complex network of DC-like cells in the gut indicates their important role in canine mucosal immunity, including active sampling of luminal antigens. Furthermore, their shift in diseased dogs suggests a pathogenetic significance for canine IBD.
[show abstract][hide abstract] ABSTRACT: Gold-bead implantation as a method of pain treatment in dogs suffering from osteoarthritic disease is receiving increasing attention in veterinary medicine. For the present article, publications from veterinary books and journals were collected and evaluated, together with related articles in human medicine. After providing an overview of the historical use of gold and gold compounds, the technique of implanting this noble metal is introduced. The reasons for establishing the terms gold acupuncture and gold (bead) implantation are described, considering the question whether and what kind of methodological differences exist behind these terms. Next, previous publications concerning the effects of gold implantation in tissue are summarised. In 2002 it was proven that gold ions are released from the surface of gold implants by a process termed dissolucytosis. Subsequent publications further investigated details about the interaction between gold ions and tissue as well as the distribution pattern of bio-released ions. Gold compounds were previously used for chrysotherapy in human medicine until medication with fewer side effects became established. The anti-inflammatory and immuno-modulatory properties of gold compounds were used to treat rheumatoid arthritis. Current research aims to ascertain whether the anti-inflammatory and immuno-modulating effects of gold compounds are imitated by gold ions released from gold implants at a local level. In conclusion, the present review summarises important findings about the effects of gold implanted in tissue. However, further research is necessary to estimate the limitations and benefits of this auromedication.
[show abstract][hide abstract] ABSTRACT: Background/Aim: Interleukin-12 (IL-12) and interferon gamma (IFN-γ) are key cytokines in immunemediated equine melanoma therapy. Currently, a method for accurate simultaneous quantification of these equine cytokines is lacking. Therefore, we sought to establish an assay that allows for accurate and simultaneous quantification of equine IL-12 (eIL-12) and IFN-γ (eIFN-γ).
Several antibodies were evaluated for cross-reactivity to eIL-12 and eIFN-γ and were used to establish a bead-based Luminex assay, which was subsequently applied to quantify cytokine concentrations in biological samples.
Cytokine detection ranged from 31.5-5,000 pg/ml and 15-10,000 pg/ml for eIL-12 and eIFN-γ, respectively. eIL-12 was detected in supernatants of stimulated peripheral blood mononuclear cells (PBMCs) and supernatants/cell lysates of eIL-12 expression plasmid-transfected cells. Low or undetectable cytokine concentrations were measured in negative controls. In equine serum samples, the mean measured eIL-12 concentration was 1,374±8 pg/ml. The bead-based assay and ELISA for eIFN-γ used to measure eIFN-γ concentrations, showed similar concentrations.
Results demonstrate, to our knowledge for the first time, that cross-reactive antibody pairs to eIL-12 and eIFN-γ and Luminex bead-based technology allow for accurate, simultaneous and multiplexed quantification of these key cytokines in biological samples.
Anticancer research 04/2013; 33(4):1325-36. · 1.71 Impact Factor
[show abstract][hide abstract] ABSTRACT: BACKGROUND: Magnetic resonance (MR) imaging is the preferred diagnostic tool to evaluate internal disorders of many joints in humans; however, the usefulness of MR imaging in the context of osteoarthritis, and joint disease in general, has yet to be characterized in veterinary medicine. The objective of this study was to assess the diagnostic accuracy of short-duration 3 Tesla MR imaging for the evaluation of cranial and caudal cruciate ligament, meniscal and cartilage damage, as well as the degree of osteoarthritis, in dogs affected by non-traumatic, naturally-occurring cranial cruciate ligament rupture (CCLR). Diagnoses made from MR images were compared to those made during surgical exploration. Twenty-one client-owned dogs were included in this study, and one experienced evaluator assessed all images. RESULTS: All cranial cruciate ligaments were correctly identified as ruptured. With one exception, all caudal cruciate ligaments were correctly identified as intact. High sensitivities and specificities were obtained when diagnosing meniscal rupture. MR images revealed additional subclinical lesions in both the cranial and caudal cruciate ligaments and in the menisci. There was a "clear" statistical (kappa) agreement between the MR and the surgical findings for both cartilage damage and degree of osteoarthritis. However, the large 95% confidence intervals indicated that evaluation of cartilage damage and of degree of osteoarthritis is not clinically satisfactory. MR imaging was not superior to radiography for the assessment of osteoarthritis. CONCLUSIONS: The presence of cruciate ligament damage and meniscal tears could be accurately assessed using the MR images obtained with our protocol. However, in the case of meniscal evaluation, occasional misdiagnosis did occur. The presence of cartilage damage and the degree of osteoarthritis could not be properly evaluated.
BMC Veterinary Research 02/2013; 9(1):40. · 1.86 Impact Factor
[show abstract][hide abstract] ABSTRACT: The discovery of the post-transcriptional gene silencing (PTGS) by small non-protein-coding RNAs is considered as a major breakthrough in biology. In the last decade we just started to realize the biologic function and complexity of gene regulation by small non-coding RNAs. PTGS is a conserved phenomenon which was observed in various species such as fungi, worms, plants, and mammals. Micro RNAs (miRNA) and small interfering RNAs (siRNAs) are two gene silencing mediators constituting an evolutionary conserved class of non-coding RNAs regulating many biological processes in eukaryotes. As this small RNAs appear to regulate gene expression at translational and transcriptional level it is not surprising that during the last decade many human diseases among them Alzheimer's disease, cardiovascular diseases, and various cancer types were associated with deregulated miRNA expression. Consequently small RNAs are considered to hold big promises as therapeutic agents. However, despite of the enormous therapeutic potential many questions remain unanswered. A major critical point, when evaluating novel therapeutic approaches, is the transfer of in vitro settings to an in vivo model. Classical animal models rely on the laboratory kept animals under artificial conditions and often missing an intact immune system. Model organisms with spontaneously occurring tumors as e.g., dogs provide the possibility to evaluate therapeutic agents under the surveillance of an in intact immune system and thereby providing an authentic tumor reacting scenario. Considering the genomic similarity between canines and humans and the advantages of the dog as cancer model system for human neoplasias the analyses of the complex role of small RNAs in canine tumor development could be of major value for both species. Herein we discuss comparatively the role of miRNAs in human and canine cancer development and highlight the potential and advantages of the model organism dog for tumor research.
[show abstract][hide abstract] ABSTRACT: Muscle tissue has a great intrinsic adaptability to changing functional demands. Triggering more gradual responses such as tissue growth, the immediate responses to altered loading conditions involve changes in the activity. Because the reduction in a limb's function is associated with marked deviations in the gait pattern, understanding the muscular responses in laming animals will provide further insight into their compensatory mechanisms as well as help to improve treatment options to prevent musculoskeletal sequelae in chronic patients. Therefore, this study evaluated the changes in muscle activity in adaptation to a moderate, short-term, weight-bearing hindlimb lameness in two leg and one back muscle using surface electromyography (SEMG). In eight sound adult dogs that trotted on an instrumented treadmill, bilateral, bipolar recordings of the m. triceps brachii, the m. vastus lateralis and the m. longissimus dorsi were obtained before and after lameness was induced. Consistent with the unchanged vertical forces as well as temporal parameters, neither the timing nor the level of activity changed significantly in the m. triceps brachii. In the ipsilateral m. vastus lateralis, peak activity and integrated SEMG area were decreased, while they were significantly increased in the contralateral hindlimb. In both sides, the duration of the muscle activity was significantly longer due to a delayed offset. These observations are in accordance with previously described kinetic and kinematic changes as well as changes in muscle mass. Adaptations in the activity of the m. longissimus dorsi concerned primarily the unilateral activity and are discussed regarding known alterations in trunk and limb motions.
PLoS ONE 01/2013; 8(11):e80987. · 3.73 Impact Factor
[show abstract][hide abstract] ABSTRACT: Objective-To evaluate the load redistribution mechanisms in walking and trotting dogs with induced forelimb lameness. Animals-7 healthy adult Beagles. Procedures-Dogs walked and trotted on an instrumented treadmill to determine control values for peak and mean vertical force as well as verticle impulse for all 4 limbs. A small sphere was attached to the ventral pad of the right forelimb paw to induce a reversible lameness, and recordings were repeated for both gaits. Additionally, footfall patterns were assessed to test for changes in temporal gait variables. Results-During walking and trotting, peak and mean vertical force as well as vertical impulse were decreased in the ipsilateral forelimb, increased in the contralateral hind limb, and remained unchanged in the ipsilateral hind limb after lameness was induced. All 3 variables were increased in the contralateral forelimb during trotting, whereas only mean vertical force and vertical impulse were increased during walking. Stance phase duration increased in the contralateral forelimb and hind limb during walking but not during trotting. Conclusions and Clinical Relevance-Analysis of the results suggested that compensatory load redistribution mechanisms in dogs depend on the gait. All 4 limbs should be evaluated in basic research and clinical studies to determine the effects of lameness on the entire body. Further studies are necessary to elucidate specific mechanisms for unloading of the affected limb and to determine the long-term effects of load changes in animals with chronic lameness.
American Journal of Veterinary Research 01/2013; 74(1):34-9. · 1.35 Impact Factor
[show abstract][hide abstract] ABSTRACT: The receptor for advanced glycation end products (RAGE) is a multiligand receptor of environmental stressors which plays key roles in pathophysiological processes, including immune/inflammatory disorders, Alzheimer's disease, diabetic arteriosclerosis, tumorigenesis, and metastasis. Besides the full-length RAGE protein in humans nearly 20 natural occurring RAGE splicing variants were described on mRNA and protein level. These naturally occurring isoforms are characterized by either N-terminally or C-terminally truncations and are discussed as possible regulators of the full-length RAGE receptor either by competitive ligand binding or by displacing the full-length protein in the membrane. Accordingly, expression deregulations of the naturally occurring isoforms were supposed to have significant effect on RAGE-mediated disorders. Thereby the soluble C-truncated RAGE isoforms present in plasma and tissues are the mostly focused isoforms in research and clinics. Deregulations of the circulating levels of soluble RAGE forms were reported in several RAGE-associated pathological disorders including for example atherosclerosis, diabetes, renal failure, Alzheimer's disease, and several cancer types.Regarding other mammalian species, the canine RAGE gene showed high similarities to the corresponding human structures indicating RAGE to be evolutionary highly conserved between both species. Similar to humans the canine RAGE showed a complex and extensive splicing activity leading to a manifold pattern of RAGE isoforms. Due to the similarities seen in several canine and human diseases-including cancer-comparative structural and functional analyses allow the development of RAGE and ligand-specific therapeutic approaches beneficial for human and veterinary medicine.
Methods in molecular biology (Clifton, N.J.) 01/2013; 963:265-76.