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T Stokol

Publications and source records attributed to T Stokol.

18 recordsLinked to original sources
PubMed2005

Effect of anticoagulant and storage conditions on bovine nonesterified fatty acid and beta-hydroxybutyrate concentrations in blood.

The objective of this study was to determine if nonesterified fatty acid (NEFA) and beta-hydroxybutyrate (BHBA) concentrations were affected by anticoagulants or gel and clot activator tubes (serum separator tubes, SST), storage of samples as whole blood, separated plasma or serum at 24 degrees C or 4 degrees C for 24 to 72 h, or storage as serum at -40 degrees C for 1 mo. Blood was collected from dairy cows into EDTA, heparin, nonanticoagulant tubes, and SST, and analyzed immediately to obtain baseline NEFA and BHBA concentrations. Portions were stored as whole blood or separated plasma or serum at 4 or 24 degrees C and assayed daily for 24 (whole blood) and 72 (separated samples) h. Serum samples were frozen at -40 degrees C and assayed at 24 h or weekly for 1 mo. Baseline NEFA concentrations were unaffected by anticoagulants; however, they were significantly higher in SST compared with nonanticoagulant tubes. Concentrations of NEFA were stable in all samples at 4 degrees C, whereas they sequentially increased from 24 to 48 h at 24 degrees C. Changes were more dramatic in heparinized samples. Serum could be stored frozen for up to 1 mo with minimal changes in NEFA concentrations. Concentrations of BHBA were stable under all conditions evaluated. Our results indicated that blood for NEFA testing should be collected into EDTA or nonanticoagulant tubes (but not SST), separated promptly from cells, and maintained at 4 degrees C until analysis.

3-Hydroxybutyric Acid↗
PubMed2000

Effect of citrate concentration on coagulation test results in dogs.

OBJECTIVE: To determine the effect of citrate concentration (3.2 vs 3.8%) on coagulation tests in dogs. DESIGN: Original study. ANIMALS: 30 clinically healthy dogs and 12 dogs with hereditary hemostatic disorders. PROCEDURE: Blood was collected from all dogs directly into collection tubes containing 3.2 or 3.8% buffered citrate. Prothrombin time (PT), activated partial thromboplastin time (aPTT), and fibrinogen concentration were measured by use of 3 clot-detection assay systems (2 mechanical and 1 photo-optic). Factor VIII and factor IX coagulant activities (FVIII:C and FIX:C, respectively) were determined by use of a manual tilt-tube method and a mechanical clot-detection device. RESULTS: Significant differences were not detected in median PT, fibrinogen concentration, FVIII:C, or FIX:C between 3.2 and 3.8% citrate for any assay system. A significant prolongation in aPTT for 3.2% citrate, compared with 3.8% citrate, was found in 1 mechanical system. CONCLUSIONS AND CLINICAL RELEVANCE: Citrate concentration does not significantly affect results of most coagulation assays, regardless of assay system. The aPTT was mildly influenced by the citrate concentration, although this was animal-, instrument-, and reagent-dependent. The choice of 3.2 or 3.8% citrate as an anticoagulant for coagulation tests has minimal influence on assay results in healthy dogs or dogs with hereditary hemostatic disorders.

Animals↗
PubMed2000

Hepatic effects of halothane and isoflurane anesthesia in goats.

OBJECTIVE: To determine hepatic effects of halothane and isoflurane anesthesia in young healthy goats. DESIGN: Randomized prospective clinical trial. ANIMALS: 24 healthy 9-month-old female goats. PROCEDURE: Goats were sedated with xylazine hydrochloride and ketamine hydrochloride and anesthetized with halothane (n = 12) or isoflurane (12) while undergoing tendon surgery. End-tidal halothane and isoflurane concentrations were maintained at 0.9 and 1.2 times the minimal alveolar concentrations, respectively, and ventilation was controlled. Venous blood samples were collected approximately 15 minutes after xylazine was administered and 24 and 48 hours after anesthesia, and serum aspartate aminotransferase (AST), sorbitol dehydrogenase (SDH), alkaline phosphatase (ALP), and gamma-glutamyltransferase (GGT) activities and bilirubin concentration were measured. Goats were euthanatized 25 or 62 days after anesthesia, and postmortem liver specimens were submitted for histologic examination. RESULTS: All goats recovered from anesthesia and survived until euthanasia. Serum SDH, GGT, and ALP activities and bilirubin concentration did not increase after anesthesia, but serum AST activity was significantly increased. However, serum hepatic enzyme activities were within reference limits at all times in all except 1 goat in which serum AST activity was high 24 and 48 hours after anesthesia. This goat had been anesthetized with halothane and had the longest duration of anesthesia. No clinically important abnormalities were seen on histologic examination of liver specimens. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that use of halothane or isoflurane for anesthesia in young healthy goats is unlikely to cause hepatic injury.

Alkaline Phosphatase↗
PubMed2000

Monoclonal immunoglobulin G cryoglobulinemia and multiple myeloma in a domestic shorthair cat.

A 13-year-old castrated domestic shorthair cat was examined because of fever, anorexia, and dermatologic lesions. Crusting, erythema, and well-demarcated purple discoloration of the foot pads and the tips of the pinnae, nose, and tail were seen. A white flocculent precipitate was detected in cooled serum. This precipitate dissolved upon rewarming, consistent with a cryoglobulin. Hypercalcemia, high alanine and aspartate aminotransferase activities, thrombocytopenia, and a monoclonal IgG gammopathy were found. Numerous hepatic nodules were detected by means of abdominal ultrasonography. Cytologic evaluation of fine-needle aspirates of the liver and spleen revealed numerous plasma cells, and evaluation of a bone marrow aspirate revealed plasmacytosis. A diagnosis of multiple myeloma and monoclonal IgG cryoglobulinemia was made, and the cat was euthanatized.

Animals↗
PubMed2000

Idiopathic pure red cell aplasia and nonregenerative immune-mediated anemia in dogs: 43 cases (1988-1999).

OBJECTIVE: To examine clinical features, laboratory test results, treatment, and outcome of dogs with pure red cell aplasia (PRCA) and idiopathic nonregenerative immune-mediated anemia (NRIMA). DESIGN: Retrospective study. ANIMALS: 43 dogs with severe nonregenerative anemia. PROCEDURE: Medical records of dogs determined to have PRCA, NRIMA, or ineffective erythropoiesis on the basis of bone marrow analysis between 1988 and 1999 were reviewed. Criteria for inclusion were > or = 5-day history of severe nonregenerative anemia (Hct < 20%; < 60.0 x 10(3) reticulocytes/microliter) with no underlying diseases. Information was retrieved on signalment, clinical signs, laboratory test results, treatment, and outcome. RESULTS: Median age of the dogs was 6.5 years. Spayed females and Labrador Retrievers were significantly overrepresented. Median Hct was 11% with no evidence of regeneration (median, 1.5 x 10(3) reticulocytes/microliter). Direct Coombs' test results were positive in 57% of dogs. Biochemical abnormalities included hyperferremia and high percentage saturation of transferrin. Bone marrow findings ranged from PRCA (5%) to erythroid hyperplasia (55%). Myelofibrosis was common. Dogs were treated with immunosuppressive drugs and the response was complete, partial, and poor in 55, 18, and 27% of the dogs, respectively. Mortality rate was 28%. CONCLUSIONS AND CLINICAL RELEVANCE: An immune-mediated pathogenesis should be considered in dogs with severe, nonregenerative anemia, normal WBC and platelet counts, hyperferremia, mild clinical signs, and no evidence of underlying disease. Bone marrow findings range from the rare PRCA to erythroid hyperplasia. Myelofibrosis is often detected in affected dogs and may prevent bone marrow aspiration.

Anemia, Hemolytic, Autoimmune↗
PubMed2000

D-dimer concentrations in healthy dogs and dogs with disseminated intravascular coagulation.

OBJECTIVE: To determine sensitivity and specificity of assays of D-dimer concentrations in dogs with disseminated intravascular coagulation (DIC) and healthy dogs and to compare these results with those of serum and plasma fibrin-fibrinogen degradation product (FDP) assays. ANIMALS: 20 dogs with DIC and 30 healthy dogs. PROCEDURE: Semi-quantitative and quantitative D-dimer concentrations were determined by use of latex-agglutination and immunoturbidometry, respectively. Fibrin-fibrinogen degradation products were measured by use of latex-agglutination. A reference range for the immunoturbidometric D-dimer concentration assay was established; sensitivity and specificity of the assay were determined at 2 cutoff concentrations (0.30 microg/ml and 0.39 microg/ml). RESULTS: Reference range for the immunoturbidometric D-dimer concentration assay was 0.08 to 0.39 microg/ml; median concentrations were significantly higher in dogs with DIC than in healthy dogs. Latex-agglutination D-dimer and serum and plasma FDP assays had similar sensitivity (85 to 100%) and specificity (90 to 100%); the immunoturbidometric assay had lower specificity (77%) at the 0.30 microg/ml cutoff and lower sensitivity (65%) at the 0.39 microg/ml cutoff. Sensitivity or specificity of the latex-agglutination D-dimer assay was not significantly improved when interpreted in series or parallel with FDP assays. CONCLUSIONS AND CLINICAL RELEVANCE: Measurement of D-dimer concentrations by latex-agglutination appears to be a sensitive and specific ancillary test for DIC in dogs. Specificity of D-dimer concentrations in dogs with systemic disease other than DIC has not been determined, therefore FDP and D-dimer assays should be performed concurrently as supportive tests for the diagnosis of DIC in dogs.

Animals↗
PubMed1999

Pure red cell aplasia in cats: 9 cases (1989-1997).

OBJECTIVE: To evaluate clinical features, laboratory test results, treatment, and outcome of FeLV-negative cats with pure red cell aplasia (PRCA) diagnosed by examination of bone marrow. DESIGN: Retrospective study. ANIMALS: 9 cats. PROCEDURE: Medical records and smears of bone marrow aspirates were reviewed to determine clinical features, laboratory test results, treatment, and outcome of this syndrome in cats. RESULTS: PRCA was diagnosed in 9 cats that were between 8 months and 3 years old. Cats had 2- to 16-day histories of lethargy and anorexia, and a severe normocytic, normochromic to hypochromic, nonregenerative anemia (Hct range, 6 to 15%; reference range, 25 to 45%). Other hematologic values were generally within reference ranges. Consistent changes in biochemical profiles included high aminotransferase activities and hyperferremia. Cats were seronegative for FeLV and feline immunodeficiency virus. Smears of bone marrow aspirates were characterized by absence of identifiable erythroid precursors and a high proportion of small lymphocytes. Abnormalities were not identified in megakaryocytes or myeloid cells. Treatment with immunosuppressive drugs (corticosteroids and cyclophosphamide or cyclosporin) resulted in resolution of anemia within 3 to 5 weeks. Most cats required long-term treatment to maintain Hct within reference range and tended to relapse when treatment frequency or dosage was decreased (especially if done rapidly) or treatment was discontinued. CLINICAL IMPLICATIONS: PRCA is a rare syndrome in young FeLV-negative cats, and is characterized by severe nonregenerative anemia and absence of erythroid cells in bone marrow. The condition requires prompt, aggressive, often long-term treatment with immunosuppressive drugs for resolution.

Animals↗
PubMed1999

Comparison of biological activity and safety of recombinant canine erythropoietin with that of recombinant human erythropoietin in clinically normal dogs.

OBJECTIVE: To determine whether recombinant canine erythropoietin (rcEPO) stimulates erythropoiesis in dogs without causing the immunogenicity problem (ie, erythroid hypoplasia) associated with recombinant human erythropoietin (rhEPO). ANIMALS: 13 clinically normal dogs. PROCEDURE: Dogs were randomly assigned to 2 groups; 1 group (n = 6) received rhEPO, whereas the other group (7) received rcEPO. Both groups received SC injections of diluent for 4 weeks before initiating treatment with erythropoietin (100 U/kg of body weight, SC, 3 times/wk). Hematocrit and absolute reticulocyte count were monitored weekly, CBC were done monthly, and bone marrow aspirates for cytologic evaluation were obtained before and at 4, 8, 16, and 24 weeks during treatment. RESULTS: Weekly mean Hct and absolute reticulocyte count increased in both groups of dogs during the first 2 weeks of treatment. For dogs receiving rhEPO, precipitous decreases in reticulocyte number and more gradual decreases in Hct were associated with development of erythroid hypoplasia. Dogs receiving rhEPO developed erythroid hypoplasia by week 4 (n = 4), 8 (1), or 16 (1). With cessation of rhEPO treatment after diagnosis of erythroid hypoplasia, RBC production recovered 5 to 11 weeks (median, 7 weeks) later. In contrast, rcEPO treatment caused sustained increases in Hct and reticulocytosis. None of the dogs receiving rcEPO developed erythroid hypoplasia. CONCLUSIONS: rcEPO stimulated erythrocyte production in clinically normal dogs during a 24-week period without causing the erythroid hypoplasia encountered in rhEPO-treated dogs. CLINICAL RELEVANCE: Because rcEPO did not cause erythroid hypoplasia, rcEPO may represent an improved option, compared with rhEPO, for treatment of erythropoietin-dependent anemia in dogs.

Animals↗
PubMed1997

Development of bone marrow toxicosis after albendazole administration in a dog and cat.

Bone marrow toxicosis was detected in a dog and cat following albendazole administration. Both animals were admitted with pancytopenia. In the dog, pancytopenia was attributed to severe panmarrow hypoplasia, whereas the cat had hypoplasia of erythroid and megakaryocytic series, but with a left-shifted granulocytic hyperplasia. Results of cytologic examination of bone marrow from both animals were compatible with acute injury. Both animals had been treated with albendazole for giardiasis prior to the onset of clinical signs. Bone marrow toxicosis was attributed to albendazole administration for the following reasons: this was the only or most recent drug administered, other causes of bone marrow toxicosis were not found, and both animals recovered rapidly with supportive care that consisted of fluid and antibiotic administration. Albendazole induced toxicosis appeared to be dose related in the dog and idiosyncratic in the cat. On the basis of the findings in this report, there is a potential for the development of albendazole induced bone marrow toxicosis in dogs and cats; therefore, veterinarians should exercise caution when using this drug.

Albendazole↗
PubMed1995

Stability of von Willebrand factor and factor VIII in canine cryoprecipitate under various conditions of storage.

The stability of factor VIII and von Willebrand factor antigen in canine cryoprecipitate obtained from seven greyhound donors was determined after storage under various conditions, including twice freezing at -70 degrees C and thawing at 37 degrees C, slow thawing at 4 degrees C, refreezing the slowly thawed cryoprecipitate at -20 degrees C and thawing at 37 degrees C and maintaining the thawed cryoprecipitate at room temperature for 24 hours. The results indicated that factor VIII and von Willebrand factor antigen were effectively concentrated during the initial cryoprecipitation procedure. The cryoprecipitate which had been thawed and refrozen under the above conditions maintained factor VIII activities and concentrations of von Willebrand factor antigen similar to those in the original thawed cryoprecipitate. Furthermore, there was no significant loss of either of the coagulation factors in cryoprecipitate which was thawed in a warm water bath and stored for 24 hours at room temperature.

Animals↗
PubMed1995

Stability of canine factor VIII and von Willebrand factor antigen concentration in the frozen state.

The stability of factor VIII and von Willebrand factor antigen concentration in the frozen state was assessed. Citrated plasma was obtained from 10 healthy, mixed breed dogs and separated into 300 microliters aliquots. One aliquot was assayed immediately and the others were frozen at either -20 degrees C or -70 degrees C. The activity of factor VIII and the concentration of von Willebrand factor antigen were measured after one week and one, two, three, four, five, six, eight and 10 months of storage. There were minor changes in both variables, particularly after four months, resulting in a decrease in the activity of factor VIII and an increase in the concentration of von Willebrand factor antigen. The changes were more pronounced at -20 degrees C. However, both factors remained relatively stable for the whole period.

Animals↗
PubMed1995

von Willebrand's disease in Dobermann dogs in Australia.

Over a 5-year period (1988-92), von Willebrand factor antigen (vWf:Ag) concentrations were determined on plasma samples from 614 Dobermanns. The vWf:Ag concentration was < 50 canine units (CU)/dL in 373 dogs (61%); these dogs were classified as carriers of the von Willebrand's disease (vWD) gene. In order to identify which dogs were at risk of haemorrhage due to vWD, we determined a cut-off vWf:Ag concentration below which dogs could be considered at risk. This cut-off was chosen in order to minimise the number of dogs genuinely at risk of haemorrhage, being wrongly classified as not at risk. This was done without sacrificing the specificity of the cut-off to any great extent. A vWf:Ag concentration of < 36 CU/dL was empirically chosen as the optimum cut-off concentration. In 282 dogs (76% of the carriers), the vWf:Ag concentration was below this cut-off and these dogs were, thus, classified as being at risk of haemorrhage due to vWD. Haemorrhage attributable to vWD was seen in 107 dogs (29% of the carriers, or 17% of all the dogs). Haemorrhage mostly followed trauma or surgery, but spontaneous genito-urinary and gastrointestinal haemorrhages were also frequent. Of these dogs, 92 were of known age, with a median of 3 years, and 102 were of known sex, with 61% being female. In 89 dogs in which the severity of haemorrhage was subjectively assessed, mild and moderate bleeding occurred with similar frequency (48% and 43%, respectively). There were 8 cases of severe haemorrhage, with two deaths.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

von Willebrand's disease in Scottish Terriers in Australia.

Over a 5-year period (1988-92), von Willebrand factor antigen (vWf:Ag) assays were performed on plasma samples from 207 Scottish Terriers. Based on these tests, 47 dogs (23%) had vWf:Ag concentrations < 50 canine units (CU)/dL and were classified as heterozygous carriers of the von Willebrand's disease (vWD) gene, while 9 (4%) had concentrations below the sensitivity of the assays and were classified as homozygous. There was thus an overall prevalence of 27% for the vWD gene in the Scottish Terriers tested. The homozygous dogs (median age 0.6 years at diagnosis) consisted of 7 males and 2 females. Eight of these had haemorrhage attributable to the disease, mostly spontaneous and from the oral mucosa. Other signs included haemorrhage induced by trauma or surgery, easy bruising and epistaxis. Many haemorrhagic episodes were severe enough to warrant therapeutic intervention and there was a single fatality. Pedigree analysis, possible in 7 of the dogs, revealed that each was the progeny of a mating between dogs with vWf:Ag concentrations < 50 CU/dL, which supported an autosomal recessive mode of inheritance. A single heterozygous carrier suffered haemorrhage after surgery that, in contrast to the homozygotes, was mild and did not require therapy. The data indicate that vWD is a significant problem in Scottish Terriers in Australia. Accordingly, we recommend that steps be taken to reduce the prevalence of the disease and thereby the number of clinically affected dogs, such as the establishment of a national testing scheme to determine the vWD status of all breeding dogs.

Animals↗
PubMedDate not supplied

Pharmacokinetics of von Willebrand factor and factor VIII in canine von Willebrand disease and haemophilia A.

The pharmacokinetics of von Willebrand factor antigen (vWf:Ag) and factor VIII coagulant (FVIII:C) activity in dogs with von Willebrand Disease (vWD) and haemophilia A, respectively, were assessed after the administration of fresh frozen plasma (FFP) and cryoprecipitate. Loading doses necessary to attain target plasma concentrations of each factor were estimated to be 63 U kg-1 BW for FFP and 13 U kg-1 BW for cryoprecipitate to reach 35 U dl-1 vWf:Ag in vWD and 23 U kg-1 BW for FFP and 4 U kg-1 BW for cryoprecipitate to reach 30 U dl-1 FVIII:C in haemophilia A. The estimated volumes of FFP required to attain these target concentrations (49 ml kg-1 BW for vWD and 20 ml kg-1 BW for haemophilia A) are approximately 10-fold higher than the volumes of cryoprecipitate required (4 ml kg-1 BW for vWD and 2 ml kg-1 BW for haemophilia A). This indicates that cryoprecipitate is a more efficient and practical means of treating or preventing haemorrhage in these two haemostatic disorders.

Animals↗
PubMedDate not supplied

Efficacy of fresh-frozen plasma and cryoprecipitate in dogs with von Willebrand's disease or hemophilia A.

Here we report the comparative efficacy of fresh-frozen plasma (FFP) and cryoprecipitate in the treatment of 2 inherited bleeding disorders in dogs. The dogs were divided into 3 groups, consisting of 4 Doberman Pinschers with type I von Willebrand's disease (vWD) (group 1), 1 Scottish Terrier with type III vWD (group 2), and 4 German Shepherd Dogs with hemophilia A (group 3). In vWD, therapeutic efficacy was determined by the ability of the products to increase von Willebrand factor antigen (vWf:Ag) concentrations above 35 canine units (CU)/dL and to correct the prolonged buccal mucosal bleeding time. Therapeutic efficacy in hemophilia A was assessed by the ability of the products to increase the factor VIII coagulant (FVIII:C) activity above 30 CU/dL. In both groups 1 and 2, higher increases in vWf:Ag were achieved with cryoprecipitate than with FFP, despite a significantly smaller total amount of vWf:Ag (in CU) being infused with cryoprecipitate. The maximum vWf:Ag attained after infusion in group 1 was dependent on both the baseline vWf:Ag concentration and on the type of infusion product. The dogs with vWD in both groups also displayed a delayed increase in FVIII:C activity after infusion of both plasma products, which is characteristic of the disease. In group 3, cryoprecipitate achieved similar increases in FVIII:C activity compared to FFP, although a significantly lesser amount of FVIII:C (in CU) was delivered with cryoprecipitate. Six of the 9 dogs treated with FFP experienced adverse effects ranging from mild pruritus to pallor and weakness, whereas none of the 9 dogs treated with cryoprecipitate had any observable adverse reactions (P = .009). Based on its efficacy and safety, we recommend cryoprecipitate over FFP for treatment or prophylaxis of hemorrhagic episodes in dogs with vWD or hemophilia A.

Animals↗
PubMedDate not supplied

Evaluation of kits for the detection of fibrin(ogen) degradation products in dogs.

The sensitivities and specificities of 3 commercial serum fibrin(ogen) degradation product (FDP) kits and 1 plasma FDP kit for the detection of FDPs in dogs were determined. Blood was collected for measurement of serum and plasma FDP concentrations from 30 healthy dogs and from 20 dogs that fulfilled clinical and laboratory criteria for disseminated intravascular coagulation. To determine the effect of hemolysis on FDP results, blood was collected simultaneously into Bothrops atrox venom-based and thrombin-based serum collection tubes for measurement of FDPs using a single serum FDP kit. The sensitivity (80-95%) and specificity (90-100%) for a positive or negative FDP result, regardless of concentration, was similar for all kits. Kits yielded discordant results in individual dogs and FDP concentrations obtained from 1 serum FDP kit were consistently higher than those from the other kits. Serum prepared from venom-based collection tubes was significantly more hemolyzed than serum prepared from thrombin-based collection tubes or citrated plasma. Hemolysis did not affect the FDP results. On the basis of these results, we conclude that commercial latex agglutination kits for detection of FDPs in serum and plasma samples from human patients are valid for use in dogs. The plasma FDP assay is a viable alternative to currently used serum FDP assays and has the advantage of using a single (citrated plasma) sample for measuring coagulation parameters and FDP concentration.

Animals↗