Stephan Neumann

Georg-August-Universität Göttingen, Göttingen, Lower Saxony, Germany

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Publications (8)9.42 Total impact

  • Article: Interleukin-6 (IL-6) serum concentrations in dogs with hepatitis and hepatic tumours compared with those with extra-hepatic inflammation and tumours.
    Stephan Neumann, Franz-Josef Kaup, Sonja Scheulen
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    ABSTRACT: Cytokines are part of pathogenesis in many diseases. Their measurement could be interesting for diagnostic purposes. One cytokine which participates in different inflammatory and neoplastic diseases is interleukin-6 (IL-6). The aim of this study was to investigate the IL-6 serum concentration in dogs with different liver diseases to show if there is any association between the cytokine serum level and the disease aetiology or the degree of the disease. IL-6 was measured in dogs with acute hepatitis, chronic hepatitis of different degrees and primary and secondary liver tumours. The data were compared with clinically healthy dogs and dogs with extra-hepatic diseases. For measurement, a commercial ELISA Kit (R&D Systems) was used. Compared with clinically healthy dogs and dogs with diabetes mellitus, all dogs with an intra- or extra-hepatic inflammatory or neoplastic disease have increased serum levels of IL-6. Dogs with acute hepatitis have significantly increased IL-6 serum concentrations compared with dogs with chronic hepatitis (P < 0.05). No significant difference between mild and moderate chronic hepatitis exists (P > 0.05). Dogs with secondary liver tumours have significantly increased IL-6 serum concentrations in comparison to dogs with primary liver tumours (P < 0.01), but both groups have comparable IL-6 serum concentration to dogs with extra-hepatic tumours. Measurement of IL-6 serum concentration may help differentiate between acute and chronic hepatitis and between primary and secondary liver tumours. Further information about the aetiology of the liver disease cannot be obtained by measuring IL-6 in the serum.
    Comparative Clinical Pathology 10/2012; 21(5):539-544.
  • Article: Plasma concentration of transforming growth factor-beta1 and hepatic fibrosis in dogs.
    Stephan Neumann, Franz-Josef Kaup, Baerbel Beardi
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    ABSTRACT: Liver fibrosis is a morphologic alteration that accompanies chronic liver diseases. Apart from analysis of liver biopsy specimens, there has been no means of diagnosing and evaluating the course of liver fibrosis in the dog. Several plasma markers, including transforming growth factor beta-1 (TGF-beta1), are used to indicate liver fibrosis in humans, but none has been validated for use in dogs. There is a significant correlation between the presence and severity of hepatic fibrosis and the plasma concentration of TGF-beta1 in humans with hepatic fibrosis and cirrhosis. The feasibility of using TGF-beta1 as a marker for hepatic fibrosis in dogs was evaluated by comparing plasma concentrations in 29 healthy dogs and 18 dogs with liver disease. The plasma concentrations of TGF-beta1, were 193 to 598 pg/mL in the healthy dogs, 143 to 475 pg/mL in the 7 dogs with mild hepatic fibrosis or none at all, and 427 to 1289 pg/mL in 11 dogs with moderate to severe hepatic fibrosis. The plasma concentrations of TGF-beta1 in the dogs with moderate to severe fibrosis differed significantly (P < 0.001) from those in the other 2 groups, whereas the concentrations in the dogs with mild or no fibrosis did not differ significantly from those in the healthy dogs (P > 0.05). It was concluded that TGF-beta1 is a potential plasma marker for hepatic fibrosis in dogs.
    Canadian journal of veterinary research = Revue canadienne de recherche vétérinaire 10/2008; 72(5):428-31. · 0.94 Impact Factor
  • Article: Myopathy and alterations in serum 3-methylhistidine in dogs with liver disease.
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    ABSTRACT: Liver disease can influence the metabolism of various other organs. Regarding the influence of liver diseases on muscles, only a few studies done on people exist. The goal of our study was to investigate the influence of liver diseases on muscles in dogs. Twenty-eight dogs with different liver diseases were investigated in this study. The diagnosis of muscle alteration was based on electromyography (EMG), creatine kinase serum activity, 3-methylhistidine serum concentration and a muscle biopsy in some cases. Our results suggest that liver diseases in dogs can be accompanied with muscle alteration. 3-Methylhistidine serum concentration as a new parameter for muscle destruction in dogs was significantly increased compared to clinical healthy dogs and was comparable to those concentrations in dogs with histologically confirmed myopathy of different types. The differentiation of the liver diseases into severe hepatitis, moderate hepatitis and liver tumours showed a significant elevation of 3-methylhistidine serum concentration in cases of liver tumours (P=0.03) and a tendency in cases of severe hepatitis (P=0.07). Based on our study we can conclude that liver diseases have an influence on muscles in dogs and 3-methylhistidine could be a useful parameter for muscle destruction.
    Research in Veterinary Science 05/2008; 84(2):178-84. · 1.65 Impact Factor
  • Article: Efficacy of a continuous, multiagent chemotherapeutic protocol versus a short-term single-agent protocol in dogs with lymphoma.
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    ABSTRACT: To compare response rates and remission and survival times in dogs with lymphoma treated with a continuous, multiagent, doxorubicin-based chemotherapeutic protocol or with a short-term single-agent protocol incorporating doxorubicin. Nonrandomized controlled clinical trial. 114 dogs with lymphoma. Dogs were treated with a chemotherapeutic protocol consisting of L-asparaginase, vincristine, cyclophosphamide, doxorubicin, methotrexate, and prednisolone (n=87) or doxorubicin alone (27). 63 of 86 (73%) dogs treated with the multiagent protocol (data on response was unavailable for 1 dog) and 14 of 27 (52%) dogs treated with the single-agent protocol had a complete remission. Dogs with lymphoma classified as substage<or=and dogs with a high BUN concentration at the time of initial diagnosis were significantly less likely to have a complete remission. No significant difference in remission or survival time could be demonstrated between treatment groups. Incidence of hematologic and gastrointestinal tract toxicoses did not differ between treatment groups, with the exception that vomiting was more common among dogs treated with the multiagent protocol. In this population of dogs, we were not able to identify any significant difference in remission or survival times between dogs with lymphoma treated with a continuous, multiagent chemotherapeutic protocol and dogs treated with a short-term single-agent protocol involving doxorubicin.
    Journal of the American Veterinary Medical Association 03/2008; 232(6):879-85. · 1.79 Impact Factor
  • Article: Plasma L-carnitine concentration in healthy dogs and dogs with hepatopathy.
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    ABSTRACT: L-Carnitine has an essential role in lipid metabolism. Disturbances of L-carnitine metabolism can influence the energy supply of the organism. L-Carnitine is synthesized exclusively in the liver. Hence, we hypothesized that liver disease can influence L-carnitine metabolism. The goal of this study was to compare plasma L-carnitine concentrations in dogs with different liver diseases of differing severity with the plasma L-carnitine concentrations of healthy dogs. Sixteen dogs with inflammatory liver disease and 12 dogs with liver neoplasia were included in the study. Liver disease was diagnosed by clinical chemistry, ultrasonography, and histology of liver biopsy specimens. L-Carnitine concentration was measured in plasma samples using mass spectrometry, and compared among groups using unpaired Student's t-tests. Compared with healthy controls (24.4 +/- 8.4 micromol/L), the plasma L-carnitine concentration in dogs with liver disease (44.2 +/- 23.7 micromol/L) was significantly higher (P<.0001). The difference in L-carnitine concentration between dogs with moderate (n=8; 33.6 +/- 13.7 micromol/L) and severe (n=8; 57.4 +/- 22.9 micromol/L) hepatitis was also significant (P=.02). No difference in plasma L-carnitine concentration was found between dogs with hepatitis and those with liver tumors. Liver disease in dogs was accompanied by elevated plasma L-carnitine concentration. The severity of hepatitis appears to influence L-carnitine concentration.
    Veterinary Clinical Pathology 07/2007; 36(2):137-40. · 1.56 Impact Factor
  • Article: Usefulness of Ki-67 proliferation marker in the cytologic identification of liver tumors in dogs.
    Stephan Neumann, Franz-Josef Kaup
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    ABSTRACT: Performing a biopsy is currently the best method of diagnosing liver disease. To reduce possible risk factors resulting from a biopsy, liver cytology can provide an alternative technique. The diagnostic accuracy of cytology for identifying liver tumors is, however, limited. The results of cytology might be improved by using immunochemistry for Ki-67, a proliferation marker, on liver cytology specimens. The purpose of this study was to investigate the value of Ki-67 immunochemistry on liver cytologic specimens from dogs for identifying neoplastic diseases of the liver, by comparing the results to histologic findings. Liver biopsy and cytology samples were obtained from 30 dogs with hepatic disease. All samples were evaluated by an anatomic pathologist and a cytopathologist. Parallel Ki-67 immunochemistry of histologic and cytologic samples was performed. The gradation of Ki-67 expression in histologic and cytologic samples was assessed. Cytologic specimens of liver tumors (n = 9) showed <50% Ki-67-positive cells. Twenty of 21 cases of non-neoplastic liver disease had no or few single Ki-67-positive cells. Using Ki-67, the diagnostic accuracy of cytologic evaluation was increased from 78% to 100% for malignant neoplasia. Based on the results of this study, the cytologic evaluation of liver together with Ki-67 immunochemistry can improve the diagnostic accuracy of cytology for liver neoplasia.
    Veterinary Clinical Pathology 06/2005; 34(2):132-6. · 1.56 Impact Factor
  • Article: Evaluation of serum L-phenylalanine concentration as indicator of liver disease in dogs: a pilot study.
    Stephan Neumann, Heike Welling, Sibylle Thuere
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    ABSTRACT: Because essential amino acids are metabolized in the liver, liver diseases may impair their catabolism. In this study, serum L-phenylalanine concentrations in 28 dogs with liver diseases were compared with those of 28 healthy dogs and 13 dogs with nonhepatic diseases. Dogs with liver diseases had significantly increased L-phenylalanine serum concentrations compared to healthy dogs (P<0.001) and to those with nonhepatic diseases (P<0.01). There were no significant differences among the L-phenylalanine serum concentrations of dogs with different degrees of liver diseases. The sensitivity and specificity of L-phenylalanine to fasting bile acids were comparable.
    Journal of the American Animal Hospital Association 43(4):193-200. · 0.96 Impact Factor
  • Article: Effectiveness of the homeopathic preparation Zeel compared with carprofen in dogs with osteoarthritis.
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    ABSTRACT: The authors compared the symptomatic effectiveness of a complex homeopathic preparation Zeel (1-3 tablets orally per day depending on body weight) to carprofen (4 mg/kg body weight) in dogs (n=68) aged >1 yr diagnosed with osteoarthritis in a multicenter, prospective, observational open-label cohort study in 12 German veterinary clinics. The active treatment period was 56 days. Symptomatic effectiveness, lameness, stiffness of movements, and pain on palpation were evaluated by treating veterinarians and owners. Clinical signs of osteoarthritis improved significantly (P<0.05) at all time points (days 1, 28, and 56) with both therapies. At the end of the treatment period, effectiveness was comparable in both groups. Both treatment regimens were well tolerated with only three treatment-related adverse events, all in the carprofen group.
    Journal of the American Animal Hospital Association 47(1):12-20. · 0.96 Impact Factor