bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of plasma antithrombin activity and D‐dimer concentration in populations of healthy cats, clinically ill cats, and cats with cardiomyopathy
Authors: Brazzell Jennifer L. , Borjesson Dori L.
Published: March 2008

Background: Current coagulation tests lack sensitivity and detect disseminated intravascular coagulation (DIC) only when it is severe. Measurement of antithrombin (AT) activity and D‐dimer concentration permits early diagnosis and more precise classification of coagulopathies in some species. Objectives: The objectives of this study were to validate and determine the diagnostic utility of a chromogenic AT assay and an immunoturbidimetric D‐dimer assay for the diagnosis of DIC in cats. Methods: Citrated plasma samples were collected from 30 healthy cats, 30 ill cats, and 13 cats with cardiomyopathy. Partial thromboplastin time, prothrombin time, fibrin(ogen) degradation products, platelet concentration, and erythrocyte morphology were determined on all samples to document the presence or the absence of DIC. AT activity and D‐dimer concentration were then measured. Results: The chromogenic AT assay was linear and precise. Mean AT activity was higher in ill cats and cats with cardiomyopathy compared with healthy cats, but the difference was only significant in ill cats (P= .003). Seven cats met the criteria for DIC. Of the cats with DIC, 2 had decreased AT activity, 1 had increased AT activity, and 4 had AT activities within normal limits. The immunoturbidimetric D‐dimer assay did not appear to accurately measure feline D‐dimer. Conclusions: The chromogenic AT assay appeared to measure AT in cats but was not useful for the diagnosis of DIC. AT may be an acute phase reactant in cats. The immunoturbidimetric D‐dimer assay was not useful for the diagnosis of DIC in cats.
Toxoplasma gondii inclusions in peripheral blood leukocytes of a red‐necked wallaby (Macropus rufogriseus)
Authors: Adkesson Michael J. , Gorman M. Elena , Hsiao Vincent , Whittington Julia K. , Langan Jennifer N.
Published: March 2008

Abstract A 2‐year‐old, male, red‐necked (Bennett's) wallaby (Macropus rufogriseus) from a zoological facility was presented for peracute onset of severe depression, unresponsiveness, ataxia, and loose feces. Serum biochemical abnormalities included azotemia, hypoalbuminemia, increased alanine aminotransferase activity, hyperbilirubinemia, hyperphosphatemia, and hyperkalemia, consistent with multi‐organ system failure. Severe thrombocytopenia suggested possible disseminated intravascular coagulation. Peripheral blood smear examination revealed numerous ovoid, protozoal inclusions within monocytes and occasionally within neutrophils. Despite aggressive supportive therapy, the patent died within 5 hours of presentation. Gross necropsy and histopathologic findings included severe multifocal necrotizing lesions in multiple organs. Numerous intralesional protozoal organisms were observed and were identified as Toxoplasma gondii by immunohistochemistry. Macropods (wallabies and kangaroos) are known to be highly susceptible to toxoplasmosis, with high mortality rates; diagnosis most often is obtained at necropsy. Detection of protozoal organisms in peripheral blood leukocytes is reported rarely and has not been documented previously in a macropod. Parasitemia in this case was attributed to severe, disseminated disease. Careful examination of peripheral blood smears in macropods suspected of toxoplasmosis may be warranted.
A subcutaneous mass on the neck of a horse
Authors: Brown Holly M. , Cuttino Elizabeth , LeRoy Bruce E.
Published: March 2008

Abstract A 25‐year‐old Arabian gelding was presented for investigation of a subcutaneous neck mass. Fine‐needle aspirates and impression smears revealed mast cells with widely varying degrees of cytoplasmic granulation and scattered eosinophils. Histopathology revealed a poorly circumscribed mass composed of sheets and bundles of mast cells with a large population of eosinophils. The mast cells were separated into numerous lobules by a heavy collagenous stroma, and multifocal collagen necrosis was present. Strong reactivity of the tumor cells for both Giemsa and toluidine blue stains confirmed the diagnosis of a mast cell tumor, and a Luna stain accentuated the eosinophilic infiltrates. Cutaneous mast cell tumors are found in many domestic animals but are uncommonly encountered in horses. Equine cutaneous mast cell tumors are usually benign, and there are no reports of visceral metastasis. Surgical excision is thought to be curative.
Plasma L‐carnitine concentration in healthy dogs and dogs with hepatopathy
Authors: Neumann Stephan , Welling Heike , Thuere Sibylle , Kaup Franz‐Josef
Published: March 2008

Background: 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. Objectives: 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. Methods: 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'st‐tests. Results: Compared with healthy controls (24.4 ± 8.4 μmol/L), the plasma L‐carnitine concentration in dogs with liver disease (44.2 ± 23.7 μmol/L) was significantly higher (P< .0001). The difference in L‐carnitine concentration between dogs with moderate (n = 8; 33.6 ± 13.7 μmol/L) and severe (n = 8; 57.4 ± 22.9 μmol/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.Conclusions:Liver disease in dogs was accompanied by elevated plasma L‐carnitine concentration. The severity of hepatitis appears to influence L‐carnitine concentration.
An update on FIV and FeLV test performance using a Bayesian statistical approach
Authors: Pinches Mark D. G. , Diesel Gillian , Helps Christopher R. , Tasker Séverine , Egan Kathy , Gruffydd‐Jones Tim J.
Published: March 2008

Background: Screening tests for feline retroviruses are thought to have high sensitivity and specificity, although previous studies that evaluated these tests have limitations. Novel statistical approaches have been developed that allow the estimation of sensitivity and specificity in situations where the true state of the disease in individual animals cannot be assured. Objective: The purpose of this study was to evaluate the sensitivity and specificity of a variety of retrovirus tests, including some screening tests, in a population of cats potentially infected with either feline leukemia virus (FeLV) and/or feline immunodeficiency virus (FIV) by using a Bayesian statistical approach. Methods: Four hundred and ninety blood samples from cats being evaluated for FIV infection were tested by 2 rapid immunomigration tests (Witness single [WS], Witness combi [WC]) and a plate–based ELISA (Petcheck) for FIV antibody, and by a newly designed real‐time polymerase chain reaction (PCR) assay for FIV provirus. Four hundred and ninety‐five blood samples from cats being evaluated for FeLV infection were tested by 2 rapid immunomigration tests (WS, WC) and a plate–based ELISA (Petcheck) for FeLV antigen, and by a FeLV virus isolation technique. Results were then analyzed by using a Bayesian statistical method. Results: For FIV tests, median sensitivity estimates were 0.98 for WS, 0.97 for WC, 0.98 for ELISA, and 0.92 for PCR. Median specificity estimates were 0.96 for WS, 0.96 for WC, 0.93 for ELISA, and 0.99 for PCR. For FeLV tests, median sensitivity estimates were 0.97 for WS, 0.97 for WC, 0.98 for ELISA, and 0.91 for virus isolation. Median specificity estimates were 0.96 for WS, 0.96 for WC, 0.98 for ELISA, and 0.99 for virus isolation. Conclusions: The use of Bayesian statistical methods overcomes a variety of methodologic problems associated with diagnostic test evaluations, including the lack of a definitive reference test. The sensitivity and the specificity of all 6 evaluated screening tests was high: however, specificity estimates were slightly lower than those reported by most recent studies.
A comparison of platelet parameters in EDTA‐ and citrate‐anticoagulated blood in dogs
Authors: Stokol Tracy , Erb Hollis N.
Published: March 2008

Background: Platelet aggregates are a common artifact in canine blood. Aggregates may affect the accuracy of platelet counts, with important consequences for patient care. Objectives: The purpose of this study was to determine if platelet counts in dogs were more accurate if blood was collected into citrate instead of EDTA as an anticoagulant. Methods: Blood was collected from 50 dogs with neoplasia admitted to the oncology service at Cornell University. EDTA and citrate Vacutainer tubes were filled with blood in random order. Platelet counts and parameters (mean platelet volume [MPV], platelet distribution width [PDW], mean platelet component concentration [MPC], platelet component distribution width [PCDW], and automated platelet clump count [APCC]) were determined using an optical‐based hematology analyzer (ADVIA 120). Blood smears from each anticoagulated sample were scored visually for platelet aggregates. Results: The median platelet count was significantly lower (median decrease, 27 × 109/L) in citrate‐anticoagulated blood compared with EDTA‐anticoagulated blood. This was attributed to platelet activation and aggregation: significantly more aggregates were seen in smears of citrate‐ than of EDTA‐anticoagulated blood. Aggregates were typically small and not detected by the analyzer. Also, the MPV and MPC (or density) were significantly higher (median increase, 3 fL) and lower (median decrease, 33 g/L) in citrate‐anticoagulated samples, respectively. Conclusions: Platelets aggregate, likely from activation, when blood from dogs with neoplasia is anticoagulated with citrate for hematology testing, resulting in lower platelet counts. Citrate also yields inaccurate results for MPV and MPC, likely because of inadequate sphering of platelets. Thus, we recommend that citrate not be used as an anticoagulant when accurate platelet counts are desired in dogs.
Beta‐2‐microglobulin levels in the cerebrospinal fluid of normal dogs and dogs with neurological disease
Authors: Muñana Karen R. , Saito Miyoko , Hoshi Fumio
Published: March 2008

Background: Cerebrospinal fluid (CSF) analysis is the basis for establishing a diagnosis of central nervous system (CNS) inflammation. However, the information provided by routine CSF analysis is limited. Determination of CSF beta‐2‐microglobulin (β2m) concentration has been used diagnostically in humans to identify inflammatory CNS disease; we hypothesized that it may have similar value in dogs. Objectives: The objective of this study was to measure β2m concentration in the CSF of clinically healthy dogs and compare the values to those observed in dogs with inflammatory CNS disease and intervertebral disc disease (IVDD). Methods: CSF was collected from 10 clinically healthy laboratory dogs and 11 dogs each with inflammatory CNS disease and IVDD. Routine CSF analysis was performed, and β2m concentration was measured by ELISA. CSF β2m concentration and CSF:serum β2m ratio were compared between groups by ANOVA. Linear relationships between CSF total nucleated cell count (TNCC), RBC count, total protein concentration, and β2m concentration were assessed by regression analysis. Results: The mean (± SD) CSF β2m concentration in clinically healthy dogs was 0.36 ± 0.05 μg/mL (cisternal) and 0.40 ± 0.07 μg/mL (lumbar). Median CSF β2m concentration in dogs with IVDD (0.46 μg/mL) and inflammatory CNS disease (0.85 μg/mL) differed from that of controls (0.36 μg/mL; P= .002). The concentration also differed between the 2 disease groups (P= .01). Five dogs with inflammatory CNS disease had CSF:serum β2m ratios >1. A correlation was identified between TNCC and β2m concentration (r= 0.69, P= .0003). Conclusions: CSF β2m concentration is higher in dogs with IVDD and inflammatory CNS disease, with highest values seen with inflammatory disease. This may be attributed in part to the correlation between CSF β2m concentration and TNCC, but also may reflect intrathecal immune activation.
Performance of 2 microtiter canine Coombs' tests
Authors: Overmann Jed A. , Sharkey Leslie C. , Weiss Doug J. , Borjesson Dori L.
Published: March 2008

Background: The Coombs' test, which detects immunoglobulin or complement on RBC surfaces, has long been the standard for laboratory confirmation of immune‐mediated hemolytic anemia (IMHA), a common cause of hemolytic anemia in the dog. This test, however, suffers from relatively low sensitivity. Optimization of test sensitivity would lead to fewer discrepancies between laboratory results and clinical diagnoses, and in some cases institution of appropriate therapy in a timely manner. Objectives: The objectives of this study were to 1) characterize the sensitivity and specificity of 2 canine Coombs' tests for the detection of IMHA, 2) document the efficacy of using multiple antisera dilutions beyond what is directed by manufacturers, and 3) evaluate the necessity of monovalent antisera in the test protocol. Methods: Sixty‐five canine whole‐blood samples submitted for Coombs' testing were evaluated. Patients were classified as IMHA positive or negative based on a set of predetermined criteria. IMHA classification was compared to Coombs' test results from 2 different Coombs' tests adapted to a microtiter‐plate format. One Coombs' test (VMRD Coombs' test) utilized a single polyvalent antiserum (VMRD, Inc, Pullman, WA, USA), while a second Coombs' test (University of Minnesota [U of MN] Coombs' test) used both polyvalent and monovalent antisera. Results: Sensitivity and specificity were 61% and 100% for the VMRD Coombs' test, and 82% and 95% for the U of MN Coombs' test. The use of multiple antisera dilutions resulted in 6 additional Coombs' positive test results. All positive Coombs' test results were positive by polyvalent antisera. Conclusions: When used in a microtiter‐plate format, the U of MN Coombs' test was a more sensitive test for the detection of IMHA in canine patients when compared to the VMRD Coombs' test. The use of multiple antisera dilutions increased test sensitivity. Sensitivity, however, was not increased by the use of monovalent antisera in the Coombs' test protocol.
Serum markers of lipid peroxidation, antioxidant enzymatic defense, and collagen degradation in an experimental (Pond‐Nuki) canine model of osteoarthritis
Authors: Goranov Nikolay V.
Published: March 2008

Background: Chondrocyte lipid peroxidation is strongly suggested to mediate collagen degradation and thus, to be involved in the pathogenesis of cartilage degradation and osteoarthritis (OA). Objectives: The objective of this study was to evaluate early changes in serum biochemical indicators of oxidative stress during the development of OA in a canine model. Methods: Experimental OA was induced in 7 dogs by transection of the anterior cruciate ligament (Pond‐Nuki model). Venous blood samples were obtained prior to the operation and on postoperative days 30, 60, and 105. The activity of serum catalase (an antioxidant enzyme), malondialdehyde (MDA) concentration (a marker of lipid peroxidation), and serum C2C neoepitope concentration (a marker of collagen type II degradation) were measured. Results: A statistically significant increase in all parameters as early as the 30th postoperative day was observed, compared with preoperative values. Serum catalase activity peaked on day 60, whereas MDA and C2C concentrations increased continuously until the end of the experimental period. A significant positive correlation was found between MDA and C2C concentrations, but not between catalase activity and MDA or C2C concentrations. Conclusions: The results support the hypothesis that oxidative stress is involved in the pathogenesis of OA in the dog based on the Pond‐Nuki model. The correlation between MDA and C2C concentrations suggests a possible association between oxidative stress and cartilage degeneration.
A true “triphasic” pattern: thoracolumbar spinal tumor in a young dog
Authors: De Lorenzi Davide , Baroni Massimo , Mandara Maria Teresa
Published: March 2008

Abstract An 8‐month‐old male Bernese Mountain Dog was referred with a history of hindlimb weakness that progressed to paresis on the right side. An intradural mass was detected in the spinal canal at the level of the 2nd and 3rd lumbar vertebrae. During surgical removal, 2 small fragments of the mass were prepared for cytologic examination by the squash technique. Cytologic examination revealed 3 different cell types: mesenchymal (stromal) cells, epithelial cells, and small undifferentiated hyperchromatic cells. On the basis of location and the triphasic cytologic pattern, a diagnosis of spinal nephroblastoma (thoracolumbar spinal tumor of young dogs) was made; histologic examination of the mass confirmed the cytologic diagnosis. To our knowledge, this is the first report of a triphasic pattern in a cytologic sample; recognizing this pattern is an important aid in reaching a definitive cytologic diagnosis.
Blood smear from a pregnant cat that died shortly after partial abortion
Authors: Weisman Jaime Lee , Woldemeskel Moges , Smith Kevin D. , Merrill Anita , Miller Debra
Published: March 2008

Abstract A 1‐year‐old, 5‐ to 6‐week pregnant cat was presented with a history of aborting 3 kittens the previous night. During the examination, the cat began to seizure and died. At necropsy, formalin‐fixed tissues and blood smears prepared from an EDTA blood sample collected via cardiac puncture were submitted to a diagnostic laboratory. Examination of the blood smears revealed numerous large (15–75 μm) clumped macrophages containing dark blue intracytoplasmic organisms consistent with Cytauxzoon merozoites. Scattered erythrophagocytic macrophages were also observed. Within several erythrocytes, 1–2 small, round, ring‐like piroplasms consistent with Cytauxzoon were observed. Histologic examination revealed numerous large, schizont‐laden macrophages filling the blood vessels of multiple organs. The cytologic and histologic findings were diagnostic for Cytaxuzoon felis infection. This case was of particular interest because of the unusually large number of organism‐laden macrophages in the cardiac blood sample, an uncommon finding in peripheral blood. Although the cat was presented for complications of abortion, it remains uncertain whether C felis organisms crossed the placenta and infected the fetuses or lead to the abortions.
Alkaline phosphatase: beyond the liver
Authors: Fernandez, Nicole J. , Kidney Beverly A.
Published: March 2008

AbstractThe alkaline phosphatases comprise a heterogeneous group of enzymes that are widely distributed in mammalian cells. They often are associated with cell membranes, but their exact physiologic function is unknown. Despite this, alkaline phosphatase activity is a very useful serum biochemical indicator of liver disease, particularly cholestatic disease. However, increases in the activity of alkaline phosphatase in serum and other body fluids may reflect physiologic or pathologic changes beyond those of hepatic origin. For example, nonhepatic increases in serum alkaline phosphatase activity are found in young animals, in pregnant and lactating females, and in association with high fat diets. Bone disease, endocrine disease, neoplasia, and other disorders can result in increased alkaline phosphatase activity. In addition, alkaline phosphatase activity may be increased due to induction by certain drugs such as glucocorticoids and anticonvulsants. In this article, we will review the physiologic and pathologic factors influencing the activity of alkaline phosphatase in serum and other body fluids, with an emphasis on disorders beyond liver disease.
Effectiveness of a computer‐based tutorial for teaching how to make a blood smear
Authors: Preast, Vanessa , Danielson, Jared , Bender, Holly , Bousson Maury
Published: March 2008

Background: Computer‐aided instruction (CAI) was developed to teach veterinary students how to make blood smears. This instruction was intended to replace the traditional instructional method in order to promote efficient use of faculty resources while maintaining learning outcomes and student satisfaction. Objectives: The purpose of this study was to evaluate the effect of a computer‐aided blood smear tutorial on 1) instructor's teaching time, 2) students' ability to make blood smears, and 3) students' ability to recognize smear quality. Methods: Three laboratory sessions for senior veterinary students were taught using traditional methods (control group) and 4 sessions were taught using the CAI tutorial (experimental group). Students in the control group received a short demonstration and lecture by the instructor at the beginning of the laboratory and then practiced making blood smears. Students in the experimental group received their instruction through the self‐paced, multimedia tutorial on a laptop computer and then practiced making blood smears. Data was collected from observation, interview, survey questionnaires, and smear evaluation by students and experts using a scoring rubric. Results: Students using the CAI made better smears and were better able to recognize smear quality. The average time the instructor spent in the room was not significantly different between groups, but the quality of the instructor time was improved with the experimental instruction. Conclusions: The tutorial implementation effectively provided students and instructors with a teaching and learning experience superior to the traditional method of instruction. Using CAI is a viable method of teaching students to make blood smears.
Evaluation of the Accutrend for lactate measurement in dogs
Authors: Stevenson, Connie K. , Kidney, Beverly A. , Duke, Tanya , Snead, Elisabeth C. R. , Jackson Marion L.
Published: March 2008

Background: Lactate concentrations are increasingly quantified in dogs using point‐of‐care instruments, but often without canine‐specific method evaluation and instrument‐specific reference intervals. Objectives: The objectives of this study were to 1) determine the precision of the Accutrend (Roche Diagnostics) for lactate determination in dogs, 2) determine the accuracy of the Accutrend using the Rapidlab 865 (Bayer Diagnostics) as the reference method, and 3) establish and compare reference intervals for lactate concentration in clinically healthy dogs for both instruments. Methods: Precision was evaluated using low and high control materials, and variable (1 drop) and fixed (25 μL) sample volumes. Accuracy was determined by comparing lactate concentrations obtained with the Accutrend with those from the Rapidlab 865 in 273 heparinized canine jugular venous blood samples from 100 clinically healthy dogs and 107 systemically ill dogs (173 samples). Lactate reference intervals were established for both analyzers using data from the 100 clinically healthy dogs. Results: The precision of the Accutrend was good (coefficients of variation, ≤5.3%) for 25‐μL samples but not when a drop was used. Lactate concentrations obtained on the Accutrend correlated poorly with those from the Rapidlab 865 (r= 0.864, mean bias = 0.66 mmol/L, 95% confidence interval [CI] = 0.57–0.76 with 95% limits of agreement =−0.87 (lower limit, 95% CI =−1.03 to −0.71) and 2.20 (upper limit, 95% CI = 2.04 to 2.36). The reference interval for canine lactate concentration on the Accutrend was 1.2–3.1 mmol/L compared with 0.46–2.31 mmol/L on the Rapidlab. Conclusion: Although precision was good with fixed sample volumes, blood lactate concentrations obtained on the Accutrend were significantly different than those on the Rapidlab 865, with systematic and random errors resulting in a positive bias. Further evaluation of the Accutrend is required before its use in dogs can be recommended.
Hematologic values in young pretraining healthy Greyhounds
Authors: Shiel, Robert E. , Brennan, Sheila F. , O'Rourke, Laurie G. , McCullough, Maureen , Mooney Carmel T.
Published: March 2008

Background: Greyhound dogs have numerous clinicopathologic differences compared with other dog breeds, most notably in their hematologic profiles. The hematologic differences are likely related to breed; however, the influence of other factors, including age, sex, and training, has not been fully determined. Objectives: The aim of this study was to assess hematologic values in young, healthy, pretraining Greyhounds and to determine the effects of age and sex on these findings. Methods: Jugular venous EDTA‐anticoagulated blood samples were collected from 43 healthy, pretraining Greyhounds between 5 and 13 months of age. Samples were analyzed within 24 hours of collection on an Abbott CELL‐DYN 3500R hematology analyzer. Mean hematologic results for different age groups, and correlation with age and sex were determined for each analyte. Results were compared with adult canine, nonbreed‐specific reference intervals. Results: From the age of 9 to 10 months, Greyhounds had higher HCT, hemoglobin concentration, and RBC counts compared with adult canine reference intervals. Younger Greyhounds (5–6 months) had values comparable with reference intervals. Mean total WBC, neutrophil, lymphocyte, and platelet counts tended to be toward the lower end or below the reference intervals. HCT, hemoglobin concentration, and RBC counts were correlated positively with age, and platelet count was correlated negatively with age. No differences were found based on sex. Conclusions:These results confirm that significant hematologic differences exist in pretraining Greyhounds by 9 to 10 months of age, when compared with adult canine, nonbreed‐specific reference intervals; however, these differences are less marked in Greyhounds 5 to 6 months old. Given these findings, it is unlikely that factors such as training or racing are responsible for differences in hematologic values between adult Greyhounds and other breeds.
Preanalytical factors affecting blood inorganic phosphate concentration in dairy cows
Authors: Montiel, Lisandro , Tremblay, Armand , Girard, Vincent , Chorfi Younes
Published: March 2008

Background: Hypophosphatemia is a condition that affects feed intake and milk production in dairy cows, and, to assess it, a precise biological parameter is needed. Plasma inorganic phosphate (Pi) can be used as a potential indicator of bioavailability of feed phosphorus in dairy cows. Objective: The purpose of this study was to evaluate the effects of sample type (serum vs. plasma), blood sampling site (jugular vs. coccygeal), and morning feeding on blood Pi concentration in dairy cows. Methods: Blood samples from 28 clinically healthy multiparous Holstein cows were analyzed for Pi concentration. The animals were sampled twice by coccygeal vessel into Vacutainer tubes both with and without sodium heparin, 3 hours after the morning feeding. In 4 additional cows, the concentration of Pi was measured in blood samples obtained simultaneously by jugular and coccygeal venipuncture into heparinized tubes before the morning feeding and 2, 4, and 6 hours after the feeding. The results were analyzed using parametric statistical tests. Results: Serum and plasma concentrations of Pi were correlated (r2= 0.999, P < .0001), but serum Pi concentration was higher than plasma Pi (P < .02). Plasma Pi concentration 2 hours after feeding tended to be higher than that before feeding in jugular samples, but the difference was not significant. There was no significant variation in plasma Pi during the morning postfeeding times, although jugular concentrations were 19% lower than coccygeal (P= .04). Conclusion: To increase the precision of plasma Pi measurements as an indicator of bioavailability of feed phosphorus, sample type, sampling time, and site must be taken into account, to correctly interpret plasma Pi concentrations.
Comparison of results from the semiautomated serum bone alkaline phosphatase isoenzyme assay with the periosteal alkaline phosphatase assay for use in rat models
Authors: Powers, Connie S. , Schultze, A. Eric , Krishnan, Venkatesh , Sato, Masahiko , Hoffmann Walter E.
Published: March 2008

Background: Assessment of bone formation activity is an important component of pharmacologic efficacy and toxicity evaluations for compounds in development for osteoporosis therapies. Antemortem biomarkers of bone formation and remodeling in rodents are uncommon. While the periosteal alkaline phosphatase (ALP) assay is a postmortem and laborious means of testing bone‐building activity, the semiautomated ALP isoenzyme assay is an antemortem assay that is performed on an automated chemistry analyzer after 2 simple dilutions of the initial serum sample and a short incubation. Objectives: The goal of our investigation was to determine if the serum bone ALP (BALP) data obtained from the semiautomated ALP isoenzyme assay had a similar pattern of response when compared with the periosteal ALP (PALP) assay for use in pharmacologic screening in rats. Methods: Serum and bone tissue samples were obtained from orchidectomized Wistar rats, a model of clinically induced osteoporosis. Subsequent bone formation was initiated via treatment with one of several compounds. In study 1, orchidectomized male rats were given either vehicle, dihydrotestosterone or a testosterone derivative subcutaneously every 4 days for 28 days. In study 2, orchidectomized male rats were given either vehicle or compounds A, B, or C by oral gavage daily for 15 days. Blood and tibias were collected at necropsy. Serum was analyzed for BALP activity using a semiautomated ALP assay. Tibias from the same rats were analyzed for PALP activity. Results: Serum BALP activity paralleled PALP activity within each group when compared with the controls. Conclusion: Our data indicate that the semiautomated serum BALP isoenzyme assay may be used as a biomarker of bone‐building potential in rat models of osteoporosis. This assay affords many advantages to investigators of musculoskeletal diseases, including the potential to measure multiple data points in a single study.
Coelomic mass in a rock dove (Columba livia)
Authors: Bédard, Christian , Lair, Stéphane , Langlois Isabelle
Published: March 2008

Abstract A 15‐year‐old domestic rock dove (Columbia livia) was presented to the Service de Médecine Zoologique of the Université de Montréal with a 10‐day history of lethargy and chronic weight loss of 1‐year duration. Ultrasonographic evaluation of the coelomic cavity revealed the presence of effusion and a well‐defined mass containing variably sized hypoechoic nodules of unknown origin. Cytologic evaluation of fine‐needle aspirates of the mass indicated a malignant epithelial tumor consisting of round cells arranged individually and in clusters, with large nuclei, prominent nucleoli, moderate anisocytosis and anisokaryosis, atypical mitoses, occasional binucleation and multinucleation, and large numbers of ruptured cells. A diagnosis of seminoma was established on histologic sections obtained at necropsy. The cytologic features of this tumor were similar to those of canine seminomas except for the presence of lymphocytes, which were not observed in significant numbers in cytologic smears or histologic sections. Seminoma should be included in the differential diagnosis for a space‐occupying mass causing organ displacement within the coelomic cavity of a male bird.
Pelger‐Huët anomaly in an Arabian horse
Authors: Grondin, Tanya M. , DeWitt, Shane F. , Keeton Kerry S.
Published: March 2008

Abstract Abstract: A 9‐year‐old Arabian mare was evaluated for a 7‐day history of malaise. Results of a CBC included a leukocyte concentration within the reference interval (8.4 × 103/μL, reference interval 6.0–14.0 × 103/μL) with an apparent degenerative left shift (segmented neutrophils 1.2 × 103/μL, reference interval 2.5–7.5 × 103/μL; hyposegmented neutrophils 1.8 × 103/μL, reference interval 0.0–0.2 × 103/μL). Serum clinical chemistry results included increased aspartate transaminase, alkaline phosphatase, and gamma‐glutamyltransferase activities. A presumptive diagnosis of hepatitis or cholangiohepatitis was made. The horse was treated with antimicrobials and the malaise quickly resolved. However, in a recheck CBC on day 13, the apparent degenerative left shift remained. Further evaluation of the blood smear revealed many hyposegmented granulocytes with coarse mature chromatin and normal cytoplasmic features. On the basis of the microscopic examination, the horse was diagnosed with Pelger‐Huët anomaly. The patient's offspring was subsequently also diagnosed with Pelger‐Huët anomaly on the basis of blood film examination. Neutrophil, eosinophil, and basophil mean nuclear scores in both affected horses (mare, range 1.5–2.6; offspring, range 1.6–3.2) were lower than those in 2 unrelated Arabian horses (range, 2.8–5.0) and 5 non‐Arabian control horses (range, 2.8–5.0). Results of immunophenotyping and phagocytosis/oxidative burst assays via flow cytometry showed no difference in the expression of myeloid–specific or adhesion molecules or in neutrophil function between affected and control horses. This is the second known report of equine Pelger‐Huët anomaly, both of which affected Arabian horses.
Outbreak of canine monocytic ehrlichiosis in Saudi Arabia
Authors: Sacchini Federico , Cessford Rory J. , Robinson Bede M.
Published: March 2008

Background: Canine monocytic ehrlichiosis (CME) is a widespread tickborne infection of canids caused by Ehrlichia canis, a gram‐negative obligatory intracellular bacteria belonging to the family Anaplasmataceae. CME is reported to have worldwide distribution, but its presence in a region requires the presence of the vector, the brown tick Rhipicephalus sanguineus. Objective: This purpose of this report was to describe an outbreak of CME in a colony of dogs resident in the eastern region of Saudi Arabia. Methods: History, presenting clinical signs, and the results of a CBC, biochemical panel, and serology (using a commercial test for E canis antibodies) were evaluated in 9 male Labrador Retrievers between October and December 2006. Results: The majority of dogs presented with severe lethargy (7/9) and acute anorexia (5/9), and had fever (7/9) and generalized lymphadenopathy (7/9). The most common laboratory abnormalities were anemia (8/9), leukopenia (7/9), and hypoalbuminemia (6/9). Thrombocytopenia was found in only 2 dogs, 1 of which had increased bleeding tendency. Ehrlichia morulae were identified in blood films from 4/9 dogs and serologic test results were positive in 7/9 dogs. Confirmation of Ehrlichia sp infection was obtained in 1 dog by using a genus‐specific real‐time PCR assay. Four dogs had tick infestation; the ticks on 1 dog were identified as R sanguineus. All of the dogs had a rapid clinical response to doxycycline hyclate. Conclusions: This report, to our knowledge, is the first to describe the presence of a pathogenic Ehrlichia organism affecting dogs in Saudi Arabia. Additional molecular studies are necessary to confirm E canis infection, and to identify the strain of the organism.
Blood coagulation times in the European brown hare (Lepus europaeus)
Authors: Pikula Jiri , Adam Vojtech , Bandouchova Hana , Beklova Miroslava , Horakova Jana , Horakova Hana , Kizek Rene , Krizkova Sona , Skocovska Blanka , Supalkova Veronika , Svoboda Michal , Treml Frantisek , Vitula Frantisek
Published: March 2008

Background: Many causes of mortality in the European brown hare, such as bacterial and viral infections, anticoagulant poisoning, and trauma, may result in hemorrhage. There are, however, no reference values concerning blood clotting in this species. Objectives: The aim of this study was to determine reference values for blood coagulation times and related parameters in healthy European brown hares. Methods: Blood samples from 30 clinically healthy adult hares (15 males and 15 females) were obtained. Hares were physically restrained for blood collection from the cephalic vein into tubes containing citrate and EDTA. Results: Mean ± SD were obtained for thrombin time (TT) (13.97 ± 1.37 seconds), prothrombin time (PT) (13.32 ± 2.15 seconds), activated partial thromboplastin time (APTT) (16.73 ± 1.86 seconds), fibrinogen concentration (2.98 ± 1.06 g/L), and platelet count (355.28 ± 128.73 × 109/L). Conclusions: Reference values for blood coagulation times and other parameters associated with blood clotting will be useful in the laboratory evaluation of hemorrhage in the European brown hare.
Analytical Study of the Effects of the Clogging of a Mechanical Precipitator Unit in Air Preheaters in a High-Performance Thermoelectric Power Plant Based on Available Data
Authors: Blanco J. M. , Peña F.
Published: March 2008

Following a detailed study of two of the mechanical precipitators in the air preheaters of a thermoelectric power plant, a large amount of ash that was deposited on one of the inlet conduits was observed, obstructing the incoming gas flow. A comparison of the available data for the two most recent hopper cleaning operations revealed that, on the one hand, the amount of ash collected by the clogged precipitator (A) was significantly less than that collected by the other (B) and, on the other hand, the temperature of the ash in the former was noticeably lower than in the latter. Prior to the cleaning of the conduits, a certain amount of damage was caused to the boiler dome, which meant that subsequent cleaning required the use of a hydrolazer, where it was noted that inlet pressures were very high. All of this indicated that the cause of the clogging was not physical. This paper provides a comprehensive analytical analysis that explains what happened, as well as resolving the situation.
Derivation of Diagnostic Requirements for a Distributed UAV Turbofan Engine Control System
Authors: Hannius Olof , Ring Dan , Karlsson Johan
Published: March 2008

This paper presents a method for deriving requirements for the efficiency of diagnostic functions in distributed electronic turbofan engine control systems. Distributed engine control systems consist of sensor, actuator, and control unit nodes that exchange data over a communication network. The method is applicable to engine control systems that are partially redundant. Traditionally, turbofan engine control systems use dual channel solutions in which all units are duplicated. Our method is intended for analyzing the diagnostic requirements for systems in which a subset of the sensors and the actuators is nonredundant. Such systems rely on intelligent monitoring and analytical redundancy to detect and tolerate failures in the nonredundant units. These techniques cannot provide perfect diagnostic coverage and, hence, our method focuses on analyzing the impact of nonperfect diagnostic coverage on the reliability and safety of distributed engine control systems. The method is based on a probabilistic analysis that combines fault trees and Markov chains. The input parameters for these models include failure rates as well as several coverage factors that characterize the performance of the diagnostic functions. Since the use of intelligent monitoring can cause false alarms, i.e., an error is falsely indicated by a diagnostic function, the parameters also include a false alarm rate. The method was used to derive the diagnostic requirements for a hypothetical unmanned aerial vehicle engine control system. Given the requirement that an engine failure due to the control system is not allowed to occur more than ten times per million hours, the diagnostic functions in a node must achieve 99% error coverage for transient faults and 90–99% error coverage for permanent faults. The system-level diagnosis must achieve 90–95% detection coverage for node failures, which are not detected by the nodes themselves. These results are based on the assumption that transient faults are 100 times more frequent than permanent faults. It is important to have a method for deriving probabilistic requirements on diagnostic functions for engine control systems that rely on analytical redundancy as a means to reduce the hardware redundancy. The proposed method allows us to do this using an existing tool (FAULTTREE+) for safety and reliability analysis.
Development and Application of an Eight-Step Global Mechanism for CFD and CRN Simulations of Lean-Premixed Combustors
Authors: Novosselov Igor V. , Malte Philip C.
Published: March 2008

In this paper, the development of an eight-step global chemical kinetic mechanism for methane oxidation with nitric oxide formation in lean-premixed combustion at elevated pressures is described and applied. In particular, the mechanism has been developed for use in computational fluid dynamics and chemical reactor network simulations of combustion in lean-premixed gas turbine engines. Special attention is focused on the ability of the mechanism to predict NOx and CO exhaust emissions. Applications of the eight-step mechanism are reported in the paper, all for high-pressure, lean-premixed, methane-air (or natural gas-air) combustion. The eight steps of the mechanism are as follows: (1) oxidation of the methane fuel to CO and H2O, (2) oxidation of the CO to CO2, (3) dissociation of the CO2 to CO, (4) flame-NO formation by the Zeldovich and nitrous oxide mechanisms, (5) flame-NO formation by the prompt and NNH mechanisms, (6) postflame-NO formation by equilibrium H-atom attack on equilibrium N2O, (7) postflame-NO formation by equilibrium O-atom attack on equilibrium N2O, and (8) postflame Zeldovich NO formation by equilibrium O-atom attack on N2.
A Novel Multifunctional Energy System (MES) for CO2 Removal With Zero Energy Penalty
Authors: Jin Hongguang , Han Wei , Gao Lin
Published: March 2008

This paper proposes a novel, multifunctional energy system (MES), in which hydrogen and electricity are cogenerated and about 90% of CO2 is removed. By integrating the methane/steam reforming reaction and combustion of coal, the natural gas and coal are utilized synthetically, and coal is burned to provide high-temperature thermal energy to the methane/steam reforming reaction. Afterwards, the resulting syngas enters a pressure swing adsorption (PSA) unit to separate about 70% of hydrogen, thereby significantly increasing the concentration of carbon dioxide from nearly 20% to 43% in the PSA tail gas. As a result, the overall efficiency of the new system becomes 63.2%. Compared to a conventional natural gas-based hydrogen plant and a coal-firing steam power plant without CO2 removal (the overall efficiency of the two systems is 63.0%), the energy penalty for CO2 removal in the new system is almost totally avoided. Based on the graphical exergy analysis, we propose that the integration of synthetic utilization of fossil fuel (natural gas and coal) and the CO2 removal process plays a significant role in zero energy penalty for CO2 removal and its liquefaction in the MES. The result obtained here provides a new approach for CO2 removal with zero or low thermal efficiency reduction (energy penalty) within an energy system.
Bacterial Growth and Cell Division: a Mycobacterial Perspective
Authors: Hett Erik C. , Rubin Eric J.
Published: March 2008

The genusMycobacteriumis best known for its two major pathogenic species,M. tuberculosisandM. leprae, the causative agents of two of the world's oldest diseases, tuberculosis and leprosy, respectively.M. tuberculosiskills approximately two million people each year and is thought to latently infect one-third of the world's population. One of the most remarkable features of the nonsporulatingM. tuberculosisis its ability to remain dormant within an individual for decades before reactivating into active tuberculosis. Thus, control of cell division is a critical part of the disease. The mycobacterial cell wall has unique characteristics and is impermeable to a number of compounds, a feature in part responsible for inherent resistance to numerous drugs. The complexity of the cell wall represents a challenge to the organism, requiring specialized mechanisms to allow cell division to occur. Besides these mycobacterial specializations, all bacteria face some common challenges when they divide. First, they must maintain their normal architecture during and after cell division. In the case of mycobacteria, that means synthesizing the many layers of complex cell wall and maintaining their rod shape. Second, they need to coordinate synthesis and breakdown of cell wall components to maintain integrity throughout division. Finally, they need to regulate cell division in response to environmental stimuli. Here we discuss these challenges and the mechanisms that mycobacteria employ to meet them. Because these organisms are difficult to study, in many cases we extrapolate from information known for gram-negative bacteria or more closely related GC-rich gram-positive organisms.
Molecular Control of Bacterial Death and Lysis
Authors: Rice Kelly C. , Bayles Kenneth W.
Published: March 2008

Although the phenomenon of bacterial cell death and lysis has been studied for over 100 years, the contribution of these important processes to bacterial physiology and development has only recently been recognized. Contemporary study of cell death and lysis in a number of different bacteria has revealed that these processes, once thought of as being passive and unregulated, are actually governed by highly complex regulatory systems. An emerging paradigm in this field suggests that, analogous to programmed cell death in eukaryotes, regulated cell death and lysis in bacteria play an important role in both developmental processes, such as competence and biofilm development, and the elimination of damaged cells, such as those irreversibly injured by environmental or antibiotic stress. Further study in this exciting field of bacterial research may provide new insight into the potential evolutionary link between control of cell death in bacteria and programmed cell death (apoptosis) in eukaryotes.
Management of toxic epidermal necrolysis and related syndromes
Authors: Mukasa Y , Craven N
Published: March 2008

Toxic epidermal necrolysis and Stevens–Johnson syndrome are rare and life-threatening diseases that often configure as medical emergencies. The majority of cases are drug reactions. The clinical picture is one of widespread epidermal necrosis and mucosal erosions. Treatment is largely supportive and must be provided in an appropriate environment. The role of steroids and other potential disease-modifying therapies has yet to be fully established by controlled studies. The significant mortality associated with these conditions dictates that an understanding of these conditions is essential for all doctors.
Follicular variant of papillary thyroid carcinoma: a diagnostic challenge for clinicians and pathologists
Authors: Salajegheh A , Petcu E B , Smith R A , Lam A K-Y
Published: March 2008

The follicular variant of papillary thyroid carcinoma (FVPTC) presents a type of papillary thyroid cancer that has created continuous diagnosis and treatment controversies among clinicians and pathologists. In this review, we describe the nomenclature, the clinical features, diagnostic problems and the molecular biology of FVPTC. It is important for clinicians to understand this entity as the diagnosis and management of this group of patient may be different from other patients with conventional PTC. The literature suggests that FVPTC behaves in a way similar, clinically, to conventional papillary thyroid carcinoma. However, there are some genotypic differences which may characterise this neoplasm. These parameters may account for the phenotypic variation described by some scientists in this type of cancer. Further understanding can only be achieved by defining strict pathological criteria, in-depth study of the molecular biology and long term follow-up of the optional patients with FVPTC.