Publications by authors named "Reinhard Mischke"

53 Publications

Challenging diagnostic work-up of a massive fluid-filled structure in the cranial abdomen of a cat.

Tierarztl Prax Ausg K Kleintiere Heimtiere 2021 Oct 12. Epub 2021 Oct 12.

Small Animal Clinic, University of Veterinary Medicine Hannover, Foundation.

A 9-year-old female, neutered European shorthair cat was presented with acute vomiting, obvious jaundice and painful enlargement of the abdomen. Icteric skin and mucous membranes in addition to severe bilirubinaemia (mainly direct bilirubin) and a large increase in liver enzyme activities were the main findings at the initial examination. Radio- and ultrasonographic evaluation revealed a massive fluid-filled structure caudal to the liver displacing abdominal organs, in particular the stomach. As this structure with a diameter of 8-10 cm occupied considerable space in the cranioventral abdomen, a detailed ultrasonographic examination of the liver and the gallbladder, and determination of the structure's association with a particular abdominal organ was initially impossible. Via ultrasound-assisted puncture under general anaesthesia 300 ml of an almost clear fluid could be aspirated. Cytological examination revealed a cyst content-like fluid with cell detritus.Further ultrasonographic and computed tomographic diagnostics followed by abdominal laparotomy finally enabled diagnosis of a cystic dilatation of the entire common bile duct and accumulation of white bile. Histopathological examination after euthanasia (requested by the owner) identified lymphoplasmacytic cholangitis and necrosis of the duodenal papilla. The massive dilatation of the common bile duct complicated its definite diagnosis by diagnostic imaging methods. It was most likely caused by a longer-standing obstruction of the bile flow by lymphoplasmacytic cholangitis with necrosis and granulation tissue formation in the area of the duodenal papilla. An interesting but initially misleading feature was the presence of white bile. The etiology of this extremely rare condition remains obscure but in the described case a manifestation of impaired hepatocyte function secondary to biliary stasis is suspected to be the cause.
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http://dx.doi.org/10.1055/a-1518-6202DOI Listing
October 2021

An Frameshift Variant Associated with Afibrinogenemia in Dachshunds.

Genes (Basel) 2021 07 13;12(7). Epub 2021 Jul 13.

Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, 30559 Hannover, Germany.

Congenital fibrinogen disorders are very rare in dogs. Cases of afibrinogenemia have been reported in Bernese Mountain, Bichon Frise, Cocker Spaniel, Collie, Lhasa Apso, Viszla, and St. Bernard dogs. In the present study, we examined four miniature wire-haired Dachshunds with afibrinogenemia and ascertained their pedigree. Homozygosity mapping and a genome-wide association study identified a candidate genomic region at 50,188,932-64,187,680 bp on CFA15 harboring (), (), and (). Sanger sequencing of all three genes in two cases and validation of the -associated mutation (:g.6296delT, NC_006597.3:g.52240694delA, rs1152388481) in pedigree members showed a perfect co-segregation with afibrinogenemia-affected phenotypes, obligate carriers, and healthy animals. In addition, the rs1152388481 variant was validated in 393 Dachshunds and samples from 33 other dog breeds. The rs1152388481 variant is predicted to modify the protein sequence of both transcripts (FGA201:p.Ile486Met and FGA-202:p.Ile555Met) leading to proteins truncated by 306 amino acids. The present data provide evidence for a novel truncating frameshift mutation that is very likely to explain the cases of severe bleeding due to afibrinogenemia in a Dachshund family. This mutation has already been spread in Dachshunds through carriers before cases were ascertained. Genetic testing allows selective breeding to prevent afibrinogenemia-affected puppies in the future.
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http://dx.doi.org/10.3390/genes12071065DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8304930PMC
July 2021

[Hypothyroidism in dogs: an overview].

Tierarztl Prax Ausg K Kleintiere Heimtiere 2021 Jun 22;49(3):195-205. Epub 2021 Jun 22.

Klinik für Kleintiere, Stiftung Tierärztliche Hochschule Hannover.

Hypothyroidism is one of the most common endocrinopathies in dogs. In rare cases, it may be associated with further endocrinopathies. The most common combination is the con-currence of hypothyroidism and hypoadrenocorticism. The diagnosis of hypothyroidism is based on the measurement of thyroid hormones (T4/fT4) and thyroid stimulating hormone (TSH). As thyroid hormone concentrations in the blood are influenced by various factors (e. g. systemic diseases or drugs), test results must be interpreted in conjunction with complaints demonstrated by the patient. In cases when diagnosis is not definite, stimulating tests or diagnostic imaging techniques (ultrasound, scintigraphy) are advisable. Dogs with hypothyroidism should be diagnosed and treated with thyroid hormones. When addiditional clinical signs are not consistent with hypothyroidism, co-existing additional endocrinopathies need to be considered. Furthermore, when treatment fails to result in the expected clinical response, the diagnosis of hypothyroidism must be subject to critical re-evaluation. This article provides an overview of the current diagnostic and treatment methods in canine hypothyroidism.
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http://dx.doi.org/10.1055/a-1367-3387DOI Listing
June 2021

Liebe Leserinnen, liebe Leser, ….

Tierarztl Prax Ausg K Kleintiere Heimtiere 2021 Apr 26;49(2):85. Epub 2021 Apr 26.

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http://dx.doi.org/10.1055/a-1351-3389DOI Listing
April 2021

Use of the "FreeStyle Libre" glucose monitoring system in diabetic cats.

Res Vet Sci 2021 Mar 18;135:253-259. Epub 2020 Sep 18.

Small Animal Clinic, University of Veterinary Medicine Hannover, Foundation, Bünteweg 9, D-30559 Hannover, Germany. Electronic address:

The aim of this study was to assess the "FreeStyle Libre" flash glucose monitoring system regarding its measurement accuracy and tolerability in cats. Results from 66 sensors applied to 34 predominantly diabetic cats are included. The behaviour during the attachment, wearing, and removal of the sensor and the skin site of attachment were assessed. Blood samples were regularly collected for comparative measurements (hexokinase method). Minimal signs of discomfort were noted, although the sensor was additionally fixed using individual skin stitches. Sensors, which stopped working in situ (70% [46/66]), had a median functional life of 8.3 (1.6-14) days. Skin reactions on the adhesive surface occurred after removal of 39% (23) of 59 sensors with assessable skin reaction (mild erythema: n = 21; superficial dermatitis: n = 2). Due to the upper limit of the measurement range of 27.8 mmol/l (500 mg/dl), the reading device displayed "Hi" in 62% (17/34) of cats repeatedly and/or for periods >1 h. Results were highly correlated with those of the reference method (r = 0.90, n = 359). 67.7% (243/359) of the "FreeStyle Libre" measurement values had a maximum deviation of 15% from reference measurements and 99.4% (357/359) were within the zones A and B of Parkes Consensus error grid analysis. In conclusion, the device proved to be practicable, less stressful for the animals and generated in general acceptable results. Although the upper limit of the measurement range is a limiting factor, the device promises to significantly facilitate the management of diabetic cats.
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http://dx.doi.org/10.1016/j.rvsc.2020.09.015DOI Listing
March 2021

The plasma proteome and the acute phase protein response in canine pyometra.

J Proteomics 2020 07 13;223:103817. Epub 2020 May 13.

VetMedZg Laboratory, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, Zagreb 10000, Croatia; Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bearsden Road, Glasgow G61 1QH, UK.

Canine pyometra is a common inflammatory disease of uterus in sexually mature bitches caused by secondary bacterial infection, leading to change in plasma proteins associated with the innate immune system. Proteomic investigation is increasingly being applied to canine diseases in order to identify and quantify significant changes in the plasma proteome. The aim of the study was to assess and quantify changes in plasma proteome profiles of healthy dogs and pyometra affected bitches using a TMT-based high-resolution quantitative proteomic approach. As a result, 22 proteins were significantly down-regulated including transthyretin, antithrombin, retinol-binding protein, vitamin D binding protein, paraoxonase 1, and kallikrein, while 16 were significantly up-regulated including haptoglobin light chain, alpha-1-acid glycoprotein, C-reactive protein precursor, and lipopolysaccharide-binding protein in dogs with pyometra. Pathway analysis indicated that acute inflammatory response, regulation of body fluid levels, protein activation cascade, the humoral immune response, and phagocytosis were affected in pyometra. Validation of biological relevance of the proteomic study was evident with significant increases in the concentrations of haptoglobin, C-reactive protein, alpha-1-acid glycoprotein, and ceruloplasmin by immunoassay. Pyometra in bitches was shown to stimulate an increase in host defence system proteins in response to inflammatory disease including the acute phase proteins. SIGNIFICANCE: The label-based high-resolution quantitative proteomics analysis and bioinformatic approach used in this study provide insight into the complex pathophysiology of inflammation associated with pyometra revealing proteins with biomarker potential. Early diagnosis and therapeutic intervention may prevent severe complications associated with advancing sepsis in dogs with pyometra. Therefore the identification of diagnostic biomarkers that, after clinical validation may be used in veterinary practice and protein relevant to pathways responding to disease are important findings of the study. Data are available via ProteomeXchange with identifier PXD015951.
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http://dx.doi.org/10.1016/j.jprot.2020.103817DOI Listing
July 2020

Reference intervals for rotational thromboelastometry measurements using the ROTEM® delta device in dogs.

Res Vet Sci 2020 Jun 23;130:26-32. Epub 2020 Jan 23.

Small Animal Clinic, University of Veterinary Medicine Hannover, Foundation, Bünteweg 9, D-30559, Hannover, Germany. Electronic address:

Aims of the present study were to define reference intervals for viscoelastic analyses of canine haemostasis using the ROTEM® delta analyser, and as a secondary aspect to determine the precision (repeatability) of this method. Blood samples from 125 clinically healthy dogs were included. Measurements were performed with commercially available activating reagents (ex-tem, in-tem and kaolin solution) as well as without activation. Additional fourfold measurements were done in 3 of the normal blood samples and in 3 samples with haemostatic alterations to evaluate the precision of the method. Coefficients of variation (CVs) for most of the ROTEM variables were < 10%. Clot formation time and maximum clot elasticity showed a wide inter-individual variation in comparison with alpha angle and maximum clot firmness. A multivariate analysis on various ROTEM parameters revealed particularly a significant influence of neuter status and a significant interrelationship between the factors sex and neuter status for measurements with different activating reagents. These results reflected the fact that significant differences occurred only between intact and neutered females, but not in males. No or only occasionally significant differences were found between groups of sex, age, and size. In conclusion, CVs demonstrated that the method delivers repeatable results in canine citrated whole blood. Established reference intervals should deliver valuable orientation for the evaluation of viscoelastic properties of clotting whole blood in dogs using the ROTEM delta analyser. Neuter status in females appeared to be the most relevant influencing factor and should be considered for the interpretation of ROTEM delta test results.
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http://dx.doi.org/10.1016/j.rvsc.2020.01.019DOI Listing
June 2020

Influence of dental restoration under general anaesthesia on the low-dose dexamethasone suppression test in dogs.

Res Vet Sci 2020 Apr 3;129:117-119. Epub 2020 Jan 3.

Institute of Agricultural and Nutritional Sciences, Animal Health Management, Natural Faculty III, Martin-Luther University Halle-Wittenberg, Theodor-Lieser-Str. 11, 06120 Halle, Germany. Electronic address:

It was the aim of the study to assess the impact of a minor surgical intervention under general anaesthesia on results of a low-dose dexamethasone suppression test (LDDST) in dogs. Five clinically healthy dogs underwent a LDDST (standard protocol) prior and 1, 4, 7, 14 and 28 days after a dental restoration under general anaesthesia. All LDDSTs revealed negative results. On all test days after intervention some dogs had basal cortisol concentrations below the reference range. Accordingly, plasma cortisol concentrations 4 and 8 h after dexamethasone injection were noticeably lower than before surgery and often even below the lower detection limit of 2.0 ng/ml. The study results may indicate a suppressive effect of a minor surgery under general anaesthesia on cortisol measurements during LDDSTs. It may be speculated that this could possibly lead to false negative test results in the postsurgical period, although transfer of these results to clinical cases is subject to limitations.
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http://dx.doi.org/10.1016/j.rvsc.2020.01.002DOI Listing
April 2020

Measurements of endogenous thrombin potential using the CAT method in cats: Reference values and influence of the direct factor Xa inhibitor apixaban.

Res Vet Sci 2019 Dec 28;127:113-121. Epub 2019 Aug 28.

Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany. Electronic address:

The aim of this study was to establish a thrombin generation assay (calibrated automated thrombogram, CAT) in cats by determining the precision (repeatability), reference values, and the sensitivity to anticoagulant treatment with the factor Xa inhibitor apixaban. The CAT method was performed on citrated plasma with different commercial tissue factor (TF) reagents (PPP Reagent 1 pM [LOW], PPP Reagent 5 pM, PPP Reagent 20 pM [HIGH]) according to the manufacturers` test instruction. Measurements in triplicate were performed in platelet poor plasma (PPP) of 58 healthy cats and in 6 cats at different times following the oral administration of 2.5 mg apixaban. The median CVs in healthy cats usually were < 10% with the exception of thrombin peak height measured using PPP Reagent 1 pM (14.6%). Reference values of all parameters showed marked inter-individual variability and depended largely on the TF concentration of the used activating reagent. Thrombin generation was significantly influenced by apixaban and reacted more sensitively than other tests of haemostasis including the prothrombin time, aPTT, and rotational elastometry. In conclusion, thrombin generation measured by the CAT method using commercially available reagents seems suitable for the examination of feline PPP and may be a valuable method to establish effective anticoagulant therapies for the feline patient and monitoring of such therapies in cats.
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http://dx.doi.org/10.1016/j.rvsc.2019.08.030DOI Listing
December 2019

Christmas disease in a Hovawart family resembling human hemophilia B Leyden is caused by a single nucleotide deletion in a highly conserved transcription factor binding site of the gene promoter.

Haematologica 2019 11 7;104(11):2307-2313. Epub 2019 Mar 7.

Institute of Genetics, University of Bern, Bern, Switzerland.

Hemophilia B is a classical monogenic, X-chromosomal, recessively transmitted bleeding disorder caused by genetic variants within the coagulation factor IX gene (). Although hemophilia B has been described in dogs, it has not yet been reported in the Hovawart breed. Here we describe the identification of a Hovawart family transmitting typical signs of an X-linked bleeding disorder. Five males were reported to suffer from recurrent hemorrhagic episodes. A blood sample from one of these males with only 2% of the normal concentration of plasma factor IX together with samples from seven relatives were provided. Next-generation sequencing of the mother and grandmother revealed a single nucleotide deletion in the promoter. Genotyping of the deletion in 1,298 dog specimens including 720 Hovawarts revealed that the mutant allele was only present in the aforementioned Hovawart family. The deletion is located 73 bp upstream of the start codon in the conserved overlapping DNA binding sites of hepatocyte nuclear factor 4α (HNF-4α) and androgen receptor (AR). The deletion only abolished binding of HNF-4α, while AR binding was unaffected as demonstrated by electrophoretic mobility shift assay using human HNF-4α and AR with double-stranded DNA probes encompassing the mutant promoter region. Luciferase reporter assays using wildtype and mutated promoter fragment constructs transfected into Hep G2 cells showed a significant reduction in expression from the mutant promoter. The data provide evidence that the deletion in the Hovawart family caused a rare type of hemophilia B resembling human hemophilia B Leyden.
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http://dx.doi.org/10.3324/haematol.2018.215426DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6821609PMC
November 2019

Bilateral femoral capital physeal fractures in an adult cat with suspected congenital primary hypothyroidism.

Tierarztl Prax Ausg K Kleintiere Heimtiere 2019 Feb 26;47(1):48-54. Epub 2019 Feb 26.

Small Animal Clinic, University of Veterinary Medicine Hannover.

A 4-year-old, neutered male European shorthair was presented for evaluation of right hind limb lameness. Radiographs revealed bilateral femoral capital physeal fractures, widened vertebral growth plates and constipation. Physical findings included lethargy, mental dullness, mild hypothermia, retarded growth, pharyngeal stridor, moderate muscle atrophy of pelvic limbs, hair coat abnormalities, and lack of defecation and urination. A thyroid panel revealed thyroid hormone values below detection limits and high thyroid stimulation hormone values. A presumptive diagnosis of congenital primary hypothyroidism was made, however also an early onset acquired primary hypothyroidism could not be ruled out. Results of the insulin-like growth factor (IGF-1) and the parathyroid hormone as well as an adrenocorticotropic hormone stimulating test were normal. A bilateral femoral head and neck excision was performed. Levothyroxine supplementation was started at a dosage of 50 µg (11 µg/kg) BID and later adjusted to 100 µg (22 µg/kg) BID based on total thyroxine concentrations. The tomcat showed full clinical recovery and normal clinical behaviour. The case shows that primary hypothyroidism may be considered in cats presented with femoral capital physeal fractures.
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http://dx.doi.org/10.1055/a-0806-8986DOI Listing
February 2019

Canine primary jejunal and colonic epithelial cells predominantly express TLR5 and TLR9 but do not change TLR expression pattern after stimulation with certain Toll-like receptor ligands.

Vet Immunol Immunopathol 2018 Dec 3;206:16-24. Epub 2018 Nov 3.

Department of Pathology, University of Veterinary Medicine Hannover, Buenteweg 17, D-30559 Hannover, Germany. Electronic address:

The intestinal mucosa is in contact with abundant luminal antigens and coordinates immune responses to differentiate commensals from pathogens. Intestinal epithelial cells (IECs) not only represent a physical barrier but also an immunologically important cell type that recognizes microbe-associated molecular patterns via Toll-like receptors (TLR). The importance of TLR expression has been elucidated for intestinal disorders in humans, mice and dogs. However, as knowledge about canine intestinal TLRs is mainly limited to the transcriptional level, the present study analyzed the protein expression of TLR2, TLR3, TLR4, TLR5 and TLR9 by primary canine IECs in the steady state and after stimulation with TLR ligands. This exhibited TLR5 and TLR9 to be predominantly expressed in canine IECs. TLR stimulation did not result in changes of the TLR expression pattern. Further studies are needed to elucidate whether this implicates hyporesponsiveness of canine IECs towards TLR stimulation under steady state conditions.
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http://dx.doi.org/10.1016/j.vetimm.2018.11.003DOI Listing
December 2018

A mild form of haemophilia A is associated with two factor VIII missense mutations in German Fleckvieh cattle.

Anim Genet 2018 Aug 18;49(4):350-351. Epub 2018 May 18.

Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Bünteweg 17p, 30559, Hannover, Germany.

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http://dx.doi.org/10.1111/age.12672DOI Listing
August 2018

[Immunosuppressive therapy in dogs and cats. Properties of drugs and their use in various immune-mediated diseases].

Tierarztl Prax Ausg K Kleintiere Heimtiere 2018 Apr 4;46(2):105-118. Epub 2018 May 4.

Veterinarians are regularly faced with the diagnosis and therapy of immune-mediated diseases. More frequently occurring immune-mediated diseases are immune-mediated hemolytic anemia, immunemediated thrombocytopenia and polyarthritis. Glucocorticoids are commonly used as first-line treatment because of their availability, efficacy and rapid action. Nevertheless, some patients do not respond to glucocorticoid therapy alone. Others require a rapid dose reduction because of severe side effects from glucocorticoid treatment. These patients benefit from adjuvant therapies. Ciclosporin preparations are licensed for use in veterinary medicine. The use of azathioprine, mycophenolate mofetil and human immunoglobulin therapy has also been documented. This article describes the mode of action of certain immunosuppressive agents and their use in selected diseases from recent literature.
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http://dx.doi.org/10.15654/TPK-180274DOI Listing
April 2018

Uncoupling the widespread occurrence of anti-NMDAR1 autoantibodies from neuropsychiatric disease in a novel autoimmune model.

Mol Psychiatry 2019 10 9;24(10):1489-1501. Epub 2018 Feb 9.

Clinical Neuroscience, Max Planck Institute of Experimental Medicine, Göttingen, Germany.

Autoantibodies of the IgG class against N-methyl-D-aspartate-receptor subunit-NR1 (NMDAR1-AB) were considered pathognomonic for anti-NMDAR encephalitis. This view has been challenged by the age-dependent seroprevalence (up to >20%) of functional NMDAR1-AB of all immunoglobulin classes found in >5000 individuals, healthy or affected by different diseases. These findings question a merely encephalitogenic role of NMDAR1-AB. Here, we show that NMDAR1-AB belong to the normal autoimmune repertoire of dogs, cats, rats, mice, baboons, and rhesus macaques, and are functional in the NMDAR1 internalization assay based on human IPSC-derived cortical neurons. The age dependence of seroprevalence is lost in nonhuman primates in captivity and in human migrants, raising the intriguing possibility that chronic life stress may be related to NMDAR1-AB formation, predominantly of the IgA class. Active immunization of ApoE and ApoE mice against four peptides of the extracellular NMDAR1 domain or ovalbumin (control) leads to high circulating levels of specific AB. After 4 weeks, the endogenously formed NMDAR1-AB (IgG) induce psychosis-like symptoms upon MK-801 challenge in ApoE mice, characterized by an open blood-brain barrier, but not in their ApoE littermates, which are indistinguishable from ovalbumin controls. Importantly, NMDAR1-AB do not induce any sign of inflammation in the brain. Immunohistochemical staining for microglial activation markers and T lymphocytes in the hippocampus yields comparable results in ApoE and ApoE mice, irrespective of immunization against NMDAR1 or ovalbumin. These data suggest that NMDAR1-AB of the IgG class shape behavioral phenotypes upon access to the brain but do not cause brain inflammation on their own.
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http://dx.doi.org/10.1038/s41380-017-0011-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6756099PMC
October 2019

Impact of bedding volume on physiological and behavioural parameters in laboratory mice.

Lab Anim 2017 Dec 1;51(6):601-612. Epub 2017 Mar 1.

1 Institute of Animal Welfare and Behaviour, University of Veterinary Medicine Hannover, Germany.

The standard housing temperature in animal facilities is substantially below the lower critical temperature of mice. This does not only endanger animal welfare, it can also jeopardize scientific research as cold stress has a major impact on mouse physiology. There is some evidence that deep bedding, comparable to nesting material, can help mice to reduce heat loss. Whenever changes are applied to the cage environment, the potential impact on experimental results, including variation, needs to be assessed. An increased variation can result in a conflict between reduction and refinement, when more animals are needed for significance due to the housing design. The aim of this study was to assess the impact of different bedding volumes (0.5 L, 1.5 L and 6 L per type III cage) on mean values and coefficient of variation (CV) of physiological (pentobarbital sleeping time, blood and anatomical parameters) and behavioural parameters (open-field and novel object recognition tests) of group-housed female and male BALB/c and C57BL/6 mice. A larger bedding volume did not interfere with the CVs, but influenced mean values of organ weights and tail lengths. Mice housed on deeper bedding showed a significant reduction in adrenal, liver, kidney and heart weights as well as an increase in tail lengths; these anatomical changes are akin to warm adaptation, and were previously observed for mice housed under warmer environments. A larger bedding volume appears to be a sensible way to reduce cold stress for laboratory mice without increasing variation in experimental results.
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http://dx.doi.org/10.1177/0023677217694400DOI Listing
December 2017

[Vergleichende Bestimmung von Gerinnungsparametern in Blutproben verschiedener Wild- und Ziervogelspezies].

Tierarztl Prax Ausg K Kleintiere Heimtiere 2017 Aug 8;45(4):246-252. Epub 2017 May 8.

Vanessa Guddorf, Klinik für Heimtiere, Reptilien, Zier- und Wildvögel, Stiftung Tierärztliche Hochschule Hannover, Bünteweg 9, 30559 Hannover, Germany, Email:

Objective: Information about the influence of species variety or diseases on coagulation values in avian blood is rare. The aim of this study was to assess the influence of species on measurements of coagulation parameters in avian plasma samples using commercially available reagents and to investigate potential influences of selected diseases on clotting times.

Material And Methods: Prothrombin time (PT), activated partial thromboplastin time (aPTT) and thrombin time (TT) were measured in citrated plasma of healthy individuals collected from eight different wild and captive avian species applying currently commercially available reagents prepared for use in humans, which were preselected in preliminary studies. The same parameters were tested in plasma samples from birds affected by aspergillosis, atherosclerosis, neoplasia and traumata.

Results: PT and aPTT showed a high interspecies variety. Irrespective of species, aPTTs were extremely long and partially exceeded the measurement range limit. Minor variations between species were seen in TT measurements. Clotting times obtained from birds affected by aspergillosis, atherosclerosis and neoplasia were not significantly different when compared to healthy birds. Plasma obtained from traumatised individuals showed significantly shorter PT and aPTT than that in healthy birds.

Conclusion And Clinical Relevance: Differences between species must be considered in diagnostic coagulation measurements in avian blood. Regardless of the avian species, aPTT measurements on avian samples appear to be of limited value. Lower PT and aPTT values reflect coagulation activation in traumatised birds.
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http://dx.doi.org/10.15654/TPK-160059DOI Listing
August 2017

[Atypical Cushing's syndrome in a dog. A case report].

Tierarztl Prax Ausg K Kleintiere Heimtiere 2017 06 27;45(3):186-192. Epub 2017 Apr 27.

Prof. Dr. Reinhard Mischke, Klinik für Kleintiere, Stiftung Tierärztliche Hochschule Hannover, Bünteweg 9, 30559 Hannover, E-Mail:

In a 12-year-old male Labrador Retriever, presented due to other disease symptoms, clinical signs of hyperadrenocorticism (polyuria, polydipsia, abdominal distention, muscle atrophy) were an incidental finding. Abnormal laboratory results and sonographic findings of the adrenal glands, but negative low-dose dexamethasone suppression tests with low basal cortisol concentrations, a negative andrenocorticotropic hormone (ACTH)-stimulation test and exclusion of iatrogenic hyperadrenocorticism, suggested an atypical hyperadrenocorticism (AHAC). Results of further examinations, particularly stimulation of progesterone production by ACTH (0 h value: 0.21 ng/ml; 1 h value: 4.9 ng/ml) and good response to therapy with trilostane, supported this diagnosis. However, it has to be critically considered, whether and to what extent additionally present diseases (arthroses, testicular tumour) played a role regarding the symptoms and laboratory results in this dog. This case illustrates the difficulties with the diagnosis of AHAC.
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http://dx.doi.org/10.15654/TPK-160255DOI Listing
June 2017

Comparison of the Poisoning Severity Score and National Poison Data System schemes for the severity assessment of animal poisonings: a pilot study.

Clin Toxicol (Phila) 2017 Aug 28;55(7):629-635. Epub 2017 Mar 28.

a Department of Exposure , Federal Institute for Risk Assessment , Berlin , Germany.

Context: To date, there are no publicly available schemes designed and evaluated specifically for severity assessment of animal poisonings. This poses challenges for the evaluation and comparison of animal poisoning exposure data.

Objective: Our objective for this pilot study was to evaluate agreement between raters using the Poisoning Severity Score (PSS) and National Poison Data System (NPDS) medical outcome scheme for severity assessment of canine exposures reported to a multistate poison center (PC) and to identify issues regarding their use for severity assessment of animal poisonings. Agreement between both schemes was also assessed.

Methods: The first 196 canine exposures reported to a multistate PC between 1 January and 31 August 2016 were selected and initial inquiry data from exposures was scored by four independent raters. Interrater agreement and agreement between the severity systems was calculated using weighted kappa (Κ) (Light's kappa). Reported clinical effects were also described.

Results: Interrater agreement for both the PSS (Κ 0.31; 95% CI 0.19, 0.43) and NPDS schemes (Κ 0.34; 95% CI 0.22, 0.44) was low. Agreement between the schemes was slight (Κ 0.05; 95% CI -0.08, 0.16) for pooled results from all four raters. For the PSS, 71.7% (n = 281) of ratings were minor, 23.0% (n = 90) moderate, and 5.4% (n = 21) severe. For the NPDS, 69.6% (n = 273) of ratings were minor, 27.0% (n = 106) moderate, and 3.3% (n = 13) severe. The top three reported clinical effects included vomiting (n = 86, 29.9%) drowsiness/lethargy (n = 38, 13.2%), and diarrhea (n = 24, 8.3%).

Discussion And Conclusions: This study shows considerable variability between raters using either the PSS or NPDS schemes for canine exposures severity assessment. The subjective nature of the schemes, the influence of intra- and interrater variation, and predominance of minor cases on the study findings should be taken into account when interpreting this data. Further evaluation of these schemes is warranted and could help inform their future use for animal poisoning severity assessment.
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http://dx.doi.org/10.1080/15563650.2017.1304554DOI Listing
August 2017

Short term storage stability at room temperature of two different platelet-rich plasma preparations from equine donors and potential impact on growth factor concentrations.

BMC Vet Res 2017 Jan 5;13(1). Epub 2017 Jan 5.

Small Animal Clinic, University of Veterinary Medicine Hannover, Foundation, Bünteweg 9, 30559, Hannover, Germany.

Background: The increasing interest in platelet-rich plasma (PRP) based therapies is as yet accompanied by inconsistent information regarding nearly all aspects of handling and application. Among these storage stability of processed platelet-rich products may be the basis for a more flexible application mode. The objective of this study was (1) to estimate the storage stability of growth factors platelet derived growth factor BB (PDGF-BB) and transforming growth factor ß1 (TGF-ß1) in both, a single-step softspin centrifugation-based pure-PRP (P-PRP, ACP®), and a gravity filtration system-based leukocyte-rich-PRP (L-PRP, E-PET), over a six hours time span after preparation at room temperature and (2) to identify possible factors influencing these growth factor concentrations in an equine model.

Results: Growth factor concentrations remained stable over the entire investigation period in L-PRP as well as P-PRP preparations revealing a mean of 3569 pg/ml PDGF-BB for E-PET and means of 1276 pg/ml PDGF-BB and 5086 pg/ml TGF-ß1 for ACP®. Pearson correlations yielded no significant impact of whole blood platelet (PLT), white blood cell (WBC) and red blood cell (RBC) counts on resulting cytokine values. In case of ACP® no significant dependencies between PLT, WBC and RBC counts of the processed platelet-rich product and resulting cytokine content occurred with exception of TGF-ß1 concentrations showing a strong correlation with the WBC content. PDGF-BB content of E-PET preparations showed a strong positive correlation with PLT and a strong negative with WBC of these preparations but not with RBC.

Conclusions: L-PRP ad modum E-PET and P-PRP ad modum ACP® are applicable over at least a six hours time span at room temperature without loss of growth factor content. Based on the results of this study factors influencing the resulting growth factor concentrations still remain questionable. Additional studies implicating a further standardization of preparation protocols are necessary to identify consistent impact on cytokine content after PRP processing.
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http://dx.doi.org/10.1186/s12917-016-0920-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5216599PMC
January 2017

Assessment of the effects of dalteparin on coagulation variables and determination of a treatment schedule for use in cats.

Am J Vet Res 2016 Jul;77(7):700-7

OBJECTIVE To determine a treatment protocol for SC administration of dalteparin to cats on the basis of currently available detailed pharmacokinetic data and to assess the effect of SC administration of dalteparin to cats on coagulation variables such as activated partial thromboplastin time (aPTT), thrombin time, and results for thromboelastometry, compared with effects on anti-activated coagulation factor X (anti-Xa) activity. ANIMALS 6 healthy domestic shorthair cats. PROCEDURES Cats received 14 injections of dalteparin (75 anti-Xa U/kg, SC) at 6-hour intervals. Blood samples were collected before and 2 hours after the first and second injections on days 1, 2, and 4. Anti-Xa activity was measured by use of a chromogenic substrate assay, aPTT and thrombin time were measured by use of an automated coagulometer, and viscoelastic measurements were obtained with thromboelastrometry. RESULTS 2 hours after the second injection, the target peak anti-Xa activity range of 0.5 to 1.0 U/mL was achieved in all cats, whereas median trough values remained below this range. Peak anti-Xa activity had only minimal effects on coagulation variables; the maximum median ratio for aPTT (in relationship to the value before the first dalteparin injection) was 1.23. CONCLUSIONS AND CLINICAL RELEVANCE Results of this study indicated that this treatment protocol resulted in reproducible anti-Xa activity in cats that was mostly within the targeted peak range of anti-Xa activity recommended for humans. Treatment in accordance with this protocol may not require routine coagulation monitoring of cats, but this must be confirmed in feline patients.
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http://dx.doi.org/10.2460/ajvr.77.7.700DOI Listing
July 2016

A Novel SLC27A4 Splice Acceptor Site Mutation in Great Danes with Ichthyosis.

PLoS One 2015 27;10(10):e0141514. Epub 2015 Oct 27.

Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Hannover, Germany.

Ichthyoses are a group of various different types of hereditary disorders affecting skin cornification. They are characterized by hyperkeratoses of different severity levels and are associated with a dry and scaling skin. Genome-wide association analysis of nine affected and 13 unaffected Great Danes revealed a genome-wide significant peak on chromosome 9 at 57-58 Mb in the region of SLC27A4. Sequence analysis of genomic DNA of SLC27A4 revealed the non-synonymous SNV SLC27A4:g.8684G>A in perfect association with ichthyosis-affection in Great Danes. The mutant transcript of SLC27A4 showed an in-frame loss of 54 base pairs in exon 8 probably induced by a new splice acceptor site motif created by the mutated A- allele of the SNV. Genotyping 413 controls from 35 different breeds of dogs and seven wolves revealed that this mutation could not be found in other populations except in Great Danes. Affected dogs revealed high amounts of mutant transcript but only low levels of the wild type transcript. Targeted analyses of SLC27A4 protein from skin tissues of three affected and two unaffected Great Danes indicated a markedly reduced or not detectable wild type and truncated protein levels in affected dogs but a high expression of wild type SLC27A4 protein in unaffected controls. Our data provide evidence of a new splice acceptor site creating SNV that results in a reduction or loss of intact SLC27A4 protein and probably explains the severe skin phenotype in Great Danes. Genetic testing will allow selective breeding to prevent ichthyosis-affected puppies in the future.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0141514PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4624637PMC
June 2016

Acute basophilic leukaemia in a three-month-old calf.

Acta Vet Scand 2015 Sep 3;57:48. Epub 2015 Sep 3.

Clinic for Cattle, University of Veterinary Medicine Hannover Foundation, Bischofsholer Damm 15, 30173, Hannover, Germany.

A three-month-old female Holstein-Friesian calf was presented with acute tetraparesis. After neurological examination a multifocal lesion in the central nervous system was suspected with the most pronounced lesions between the third thoracic and the third lumbar vertebrae. Haematological examination revealed moderate anaemia as well as severe thrombocytopenia, neutropenia and leucocytosis. A blood smear and bone marrow aspirate exhibited predominantly blasts with basophilic granulation leading to a diagnosis of acute (myeloid) leukaemia with involvement of the basophilic lineage or an acute basophilic leukaemia. Magnetic resonance imaging revealed spinal cord compression; at necropsy, extensive localised haemorrhages extending into the thoracic vertebral canal were found. Histopathology revealed a large population of blast cells in several tissues including the meninges. Due to multifocal detection of neoplastic cells in the vascular system, neoplasia of the haematopoietic system was assumed in agreement with haematological findings. Signs of paresis could be explained by intramedullary spinal cord haemorrhage and myeloid infiltrations of meningeal vessels. In conclusion, despite its rarity, acute myeloid leukaemia with involvement of the basophilic lineage may be considered in diagnosing calves with progressive deteriorating general condition, paresis, leucocytosis with moderate basophilic differentiation or haemorrhagic disorders.
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http://dx.doi.org/10.1186/s13028-015-0141-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4558832PMC
September 2015

Platelet function in dogs with bacterial infections and leishmaniasis.

Berl Munch Tierarztl Wochenschr 2015 Jul-Aug;128(7-8):289-96

The objective of this study was to examine the influence of bacterial infections or leishmaniasis on primary haemostasis in dogs. Capillary bleeding time, automatic platelet function analysis (PFA-100), turbidimetric platelet aggregation, impedance aggregometry, platelet count and, in addition, the haematocrit were investigated in 25 dogs with bacterial infections or leishmaniasis . Results of these diseased dogs were compared to the control group and additionally classified into two subgroups based on criteria of systemic inflammatory response syndrome (SIRS) (groups "SIRS" and "Non-SIRS"). Dogs with infections had a significantly prolonged closure time of the PFA-100 using both cartridges (e. g., collagen/ADP: 83 [55-301] vs. 65 [47-99 s; median [minimum-maximum]; p < 0.0001), a significant decrease in maximal aggregation of the turbidimetric aggregometry (e. g., ADP-induced: 45.2 ± 26.8 vs. 67.3 ± 21.8%; mean ± SD; P = 0.003), a significant increase of collagen-induced impedance aggregometry and a significant suppression of arachidonic acid-induced impedance aggregometry. An enhanced collagen-induced impedance aggregation was the only significant difference between subgroups "SIRS"and "Non-SIRS". In conclusion, although individual tests indicate enhanced platelet aggregation, most of the in vitro tests revealed a normal to moderately reduced functionality. The reduced aggregabiity may partly indicate preactivation of platelets.
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October 2015

Methodical aspects of blood coagulation measurements in birds applying commercial reagents--a pilot study.

Berl Munch Tierarztl Wochenschr 2014 Jul-Aug;127(7-8):322-7

The aim of this study was to examine the suitability of commercially available reagents for measurements of coagulation parameters in citrated plasma from birds. Therefore, plasma samples of 17 healthy donor birds of different species were used to determine prothrombin time (PT), activated partial thromboplastin time (aPTT) and thrombin time (TT) applying various commercial reagents which are routinely used in coagulation diagnostics in humans and mammals. A PT reagent based on human placental thromboplastin yielded not only shorter clotting times than a reagent containing recombinant human tissue factor (median 49 vs. 84 s), but also showed a minor range of distribution of values (43-55 s vs. 30-147 s, minimum-maximum, n = 5 turkeys). An aPTT reagent containing kaolin and phospholipids of animal origin delivered the shortest clotting times and the lowest range of variation in comparison to three other reagents of different composition. However, even when this reagent was used, aPTTs were partially extremely long (> 200 s). Thrombin time was 38 s (28-57 s, n = 5 chicken) when measured with bovine thrombin at a final concentration of 2 IU thrombin/ ml. Coefficients of variation for within-run precision analysis (20 repetitions) of PT was 8.0% and 4.7% for aPTT measurements using selected reagents of mammalian origin. In conclusion, of the commercially available reagents tested, a PT reagent based on human placental thromboplastin and an aPTT reagent including rabbit brain phospholipid and kaolin, show some promise for potential use in birds.
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July 2015

Canine epidermal lipid sampling by skin scrub revealed variations between different body sites and normal and atopic dogs.

BMC Vet Res 2014 Jul 10;10:152. Epub 2014 Jul 10.

Small Animal Clinic, University of Veterinary Medicine Hannover, Foundation, Buenteweg 9, Hanover 30559, Germany.

Background: Previously, we evaluated a minimally invasive epidermal lipid sampling method called skin scrub, which achieved reproducible and comparable results to skin scraping. The present study aimed at investigating regional variations in canine epidermal lipid composition using the skin scrub technique and its suitability for collecting skin lipids in dogs suffering from certain skin diseases. Eight different body sites (5 highly and 3 lowly predisposed for atopic lesions) were sampled by skin scrub in 8 control dogs with normal skin. Additionally, lesional and non-lesional skin was sampled from 12 atopic dogs and 4 dogs with other skin diseases by skin scrub. Lipid fractions were separated by high performance thin layer chromatography and analysed densitometrically.

Results: No significant differences in total lipid content were found among the body sites tested in the control dogs. However, the pinna, lip and caudal back contained significantly lower concentrations of ceramides, whereas the palmar metacarpus and the axillary region contained significantly higher amounts of ceramides and cholesterol than most other body sites. The amount of total lipids and ceramides including all ceramide classes were significantly lower in both lesional and non-lesional skin of atopic dogs compared to normal skin, with the reduction being more pronounced in lesional skin. The sampling by skin scrub was relatively painless and caused only slight erythema at the sampled areas but no oedema. Histological examinations of skin biopsies at 2 skin scrubbed areas revealed a potential lipid extraction from the transition zone between stratum corneum and granulosum.

Conclusions: The present study revealed regional variations in the epidermal lipid and ceramide composition in dogs without skin abnormalities but no connection between lipid composition and predilection sites for canine atopic dermatitis lesions. The skin scrub technique proved to be a practicable sampling method for canine epidermal lipids, revealed satisfying results regarding alterations of skin lipid composition in canine atopic dermatitis and might be suitable for epidermal lipid investigations of further canine skin diseases. Although the ceramide composition should be unaffected by the deeper lipid sampling of skin scrub compared to other sampling methods, further studies are required to determine methodological differences.
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http://dx.doi.org/10.1186/1746-6148-10-152DOI Listing
July 2014

Enoxaparin: pharmacokinetics and treatment schedule for cats.

Vet J 2014 Jun 1;200(3):375-81. Epub 2014 Apr 1.

Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Bünteweg 17, D-30559 Hannover, Germany.

Detailed pharmacokinetic data are not available for subcutaneously (SC) administered enoxaparin in cats and this causes difficulties in establishing treatment protocols. The aims of this study were (1) to establish pharmacokinetic data of SC administered enoxaparin and (2) to establish a treatment schedule. Six healthy cats received a single SC injection of 1 mg enoxaparin/kg and blood samples were collected before and 1, 2, 3, 4, 6, 8, 10 and 12 h after the injection. Six further healthy cats received 0.75 mg/kg every 6 h for four consecutive days and blood samples were collected before and 2 h after the first and second injection on day 1, and the first injection on days 2 and 4. Anti-factor Xa (FXa) activity, coagulation tests and thromboelastometry assays were performed. Enoxaparin injection was well tolerated. Following the single SC injection Cmax was 0.83 ± 0.08 anti-Xa IU/mL and in 5/6 cats was detected after 2 h (Tmax = 110 ± 25 min). The total clearance was 23.4 ± 4.8 mL/h/kg and the terminal half-life was 2.27 ± 0.4 h. All cats receiving repeated injections reached the defined target peak range of 0.5-1.0 IU/mL by 2 h after the second injection (0.54 [0.50-0.61]; median, [minimum - maximum]) and there was no considerable accumulation subsequently. With the exception of thromboelastometry (especially non-activated), ratio values of coagulation times increased significantly although only slightly (e.g., the maximal value of median activated partial thromboplastin time ratio was 1.27). Significant, although only moderately close relationships with Spearman rank correlation coefficients between 0.424 and 0.558 were calculated between anti-FXa activities and ratios of different coagulation times. A dosage schedule of 0.75 mg/kg four times a day seems suitable for therapeutic use of enoxaparin in cats as it leads to reproducible peak anti-FXa activities within the target range for the treatment of thrombosis in humans. The low inter-individual variation may indicate that monitoring based on anti-FXa activities is not necessary.
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http://dx.doi.org/10.1016/j.tvjl.2014.03.032DOI Listing
June 2014

Infection-associated platelet dysfunction of canine platelets detected in a flow chamber model.

BMC Vet Res 2013 Jun 7;9:112. Epub 2013 Jun 7.

Department of Anesthesiology and Intensive Care Medicine, Hannover Medical School, Carl-Neuberg-Straße 1, Hannover D-30625, Germany.

Background: In the present study, the influence of bacterial infection, lipopolysacharides (LPS) and hydroxyethyl starch (HES) on platelet function in a parallel plate flow chamber were measured. Experiments were performed with non-activated and protease-activating-receptor (PAR) 4 agonist activated platelets. Comparative measurements were in vivo capillary bleeding time, platelet function analyzer and impedance aggregometry.

Results: PAR 4 agonist did not increase platelet adhesion of platelets from dogs with bacterial inflammation in the flow chamber in contrast to platelets of healthy dogs. Except from impedance aggregometry with lower sensitivity and specificity, PFA did not detect platelet dysfunctions in dogs with infection. In vitro addition of LPS or HES significantly reduced platelet covered area after PAR-activation.

Conclusions: The flow chamber detects platelet dysfunctions in dogs with inflammatory diseases. In vitro addition of LPS highlights the inhibiting effect of bacterial wall components on platelet function. Platelet dysfunction induced by infection could possibly also be diagnosed after treatment of sepsis with colloids has commenced. The flow chamber could be a useful tool to detect sepsis associated platelet dysfunction given that larger prospective trials confirm these findings from a proof of concept study.
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http://dx.doi.org/10.1186/1746-6148-9-112DOI Listing
June 2013

Sphingosine-1-phosphate exhibits anti-proliferative and anti-inflammatory effects in mouse models of psoriasis.

J Dermatol Sci 2013 Jul 6;71(1):29-36. Epub 2013 Apr 6.

Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany.

Background: It has been indicated that the sphingolipid sphingosine-1-phosphate (S1P) restrains the ability of dendritic cells to migrate to lymph nodes. Furthermore S1P has been demonstrated to inhibit cell growth in human keratinocytes. However, only little is known about the effect of S1P in hyperproliferative and inflammatory in vivo models.

Objective: In this study, locally acting S1P was explored in different experimental mouse models of psoriasis vulgaris.

Methods: S1P and FTY720 were tested in the imiquimod-induced psoriasis mouse model, the mouse tail assay and a pilot study of the severe combined immunodeficiency mice (SCID).

Results: In the imiquimod model the positive control diflorasone diacetate and S1P, but not FTY720 reduced the imiquimod-induced epidermal hyperproliferation of the ear skin. This effect was confirmed in the SCID model, where S1P treated skin from patients suffering from psoriasis showed a decrease in epidermal thickness compared to vehicle. In the imiquimod model, there was also significant inhibition of ear swelling and a moderate reduction of inflammatory cell influx and oedema formation in ear skin by S1P treatment. The inflammatory response on the back skin was, however, only reduced by diflorasone diacetate. In the mouse tail assay, the influence of S1P and FTY720 in stratum granulosum formation was tested compared to the positive control calcipotriol. Whereas topical administration of calcipotriol led to a low but significant increase of stratum granulosum, S1P and FTY720 lacked such an effect.

Conclusion: Taken together, these results imply that topical administration of S1P might be a new option for the treatment of mild to moderate psoriasis lesions.
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http://dx.doi.org/10.1016/j.jdermsci.2013.03.006DOI Listing
July 2013

A dynamic flow-chamber-based adhesion assay to assess canine platelet-matrix interactions in vitro.

Vet Clin Pathol 2013 Jun 29;42(2):150-6. Epub 2013 Apr 29.

Department of Anesthesiology and Intensive Care Medicine, Hannover Medical School, Hannover, Germany.

Background: Dynamic adhesion assays allow the examination of platelet dysfunction and drug effects on platelet function.

Objective: The purpose of the study was to optimize several parameters such as type and concentration of collagen, wall shear stress, and the concentration of the platelet-activating agonist in a new biochip perfusion chamber for the study of canine platelets.

Methods: After fluorescent staining of platelets, citrated blood of 10 healthy dogs was perfused through the flow chamber coated with different concentrations of canine or bovine skin collagen. Wall shear stress ranged from 14 to 60 dynes/cm(2). Protease-activating receptor 4 (PAR 4) agonist was used for platelet activation. After perfusion, platelet attachment to the collagen matrix was quantified based on fluorescent imaging. Total platelet covered area and average size of platelet covered areas were measured by planimetry.

Results: Canine platelet adhesion was supported by ≥ 200 μg/mL canine collagen, but not bovine skin collagen. Consistent results were obtained with a wall shear stress of 14 dynes/cm(2), whereas higher wall shear stress resulted in increased variability. Platelet activation with PAR 4 agonist increased the total platelet covered area and the average size of platelet covered areas.

Conclusions: This study indicates the need to carefully select collagen type and concentration to assess canine thrombus formation in a dynamic flow chamber. The established method should be a useful tool to determine changes in platelet-matrix interactions as an indicator of platelet activation or platelet dysfunction in dogs.
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http://dx.doi.org/10.1111/vcp.12035DOI Listing
June 2013
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