bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detection of novel chlamydiae in cats with ocular disease
Authors: von Bomhard Wolf , Polkinghorne Adam , Huat Lu Zen , Vaughan Lloyd , Vögtlin Andrea , Zimmermann Dieter R. , Spiess Bernhard , Pospischil Andreas 
Published: January 2006

AbstractObjective—To detect and characterize the full range of chlamydial infections in cats with ocular disease by use of polymerase chain reaction (PCR) assays, cytologic examination, immunohistochemical analysis, and evaluation of clinical information including status for feline herpesvirus-1 (FeHV-1).Sample Population—DNA extracted from 226 conjunctival samples obtained from cats with clinically diagnosed keratitis or conjunctivitis and 30 conjunctival samples from healthy cats.Procedure—PCR assays for the 16S rRNA gene specific for the order Chlamydiales and a newChlamydophila felis(formerlyChlamydia psittaci) species-specific 23S rRNA gene were performed. Seventy-four conjunctival samples were prepared with Romanowsky-type stain, grouped on the basis of inflammatory pattern, and screened for chlamydial inclusions by use of immunohistochemical analysis. Clinical information and FeHV-1 status were recorded.Results—26 (12%) specimens had positive results for the only known feline chlamydial pathogen,C felis. Surprisingly, an additional 88 (39%) were positive for non-C felischlamydial DNA. Identification of non-C felischlamydial DNA by direct sequencing revealed 16S rRNA gene sequences that were 99% homologous to the sequence forNeochlamydia hartmannellae, an amebic endosymbiont. Chlamydial prevalence was significantly higher in cats with ocular disease.Conclusions and Clinical Relevance—Application of a broad-range detection method resulted in identification of a new agent associated with ocular disease in cats. Finding chlamydia-like agents such asN hartmannellaein coinfections with their obligate amebic host,Hartmannella vermiformis, raises questions about the potential role of these microorganisms in causation or exacerbation of ocular disease in cats. (Am J Vet Res2003;64:1421–1428)
Characterization and comparison of the responses of equine digital arteries and veins to endothelin-1
Authors: Katz Lisa M. , Marr Celia M. , Elliott Jonathan 
Published: January 2006

AbstractObjective—To compare the responses of equine digital arteries (EDAs) and equine digital veins (EDVs) to endothelin-1 (ET-1) and determine the role of the endothelium and type of receptors involved in the modulation and mediation of those responses, respectively.Sample Population—5 to 9 palmar digital vessels/experiment from 28 healthy horses.Procedure—Rings of dissected vessels were mounted under tension between force transducer wires in organ baths containing Krebs-Henseleit solution at 30oC. Responses of EDAs and EDVs (with intact [+e] or denuded [–e] endothelium) to cumulative concentrations of ET-1 (10–10to 3 × 10–7M) were compared. For (+e)EDAs and (+e)EDVs precontracted with a thromboxane-mimetic (U44069; 10–8M) and (–e)EDAs and (–e)EDVs, responses to an ETBreceptor agonist (S6c; 10–10to 3 × 10–7 M) were evaluated. Responses to ET-1 (10–7M) in (–e)EDAs and (–e)EDVs were evaluated after incubation with an ETAreceptor antagonist (BQ- 123; 3 × 10–7M), an ETBreceptor antagonist (BQ-788; 3 × 10–7M), or vehicle solution.Results—Endothelin-1 induced a concentrationdependent contraction of endothelium-intact and -denuded EDAs and EDVs; EDVs were more sensitive. Neither vessel type relaxed in response to S6c, although 2 of the (–e)EDAs contracted mildly. Whereas BQ-123 inhibited the (–e)EDA and (–e)EDV responses to ET-1, BQ-788 had no effect.Conclusions and Clinical Relevance—Endothelin-1 induced digital vasoconstriction (marked constriction in veins). This action was unaffected by endothelium and mediated predominantly by ETAreceptors. These findings suggest ET-1 can induce selective digital venoconstriction. (Am J Vet Res2003;64:1438–1443
Effects of duration of isoflurane anesthesia and mode of ventilation on intracranial and cerebral perfusion pressures in horses
Authors: Brosnan Robert J. , Steffey Eugene P. , LeCouteur Richard A. , Farver Thomas B. , Imai Ayako 
Published: January 2006

AbstractObjective—To test the hypothesis that isofluraneanesthetized horses during controlled ventilation and spontaneous ventilation exhibit temporal changes in cerebral hemodynamics, as measured by intracranial pressure and cerebral perfusion pressure, that reflect temporal changes in systemic arterial pressure.Animals—6 healthy adult horses.Procedure—Horses were anesthetized in left lateral recumbency with 1.57% isoflurane in O2for 5 hours in 2 experiments by use of either controlled ventilation (with normocapnia) or spontaneous ventilation (with hypercapnia) in a randomized crossover design. Intracranial pressure was measured with a subarachnoid strain-gauge transducer. Carotid artery pressure, central venous pressure, airway pressures, blood gases, and minute ventilation also were measured.Results—Intracranial pressure during controlled ventilation significantly increased during constant dose isoflurane anesthesia and thus contributed to decreasing cerebral perfusion pressure. Intracranial pressure was initially higher during spontaneous ventilation than during controlled ventilation, but this difference disappeared over time; no significant differences in cerebral perfusion pressures were observed between horses that had spontaneous or controlled ventilation.Conclusions and Clinical Relevance—Cerebral hemodynamics and their association with ventilation mode are altered over time in isoflurane-anesthetized horses and could contribute to decreased cerebral perfusion during prolonged anesthesia. (Am J Vet Res2003;64:1444–1448)
Spectral analysis of heart rate variability in dogs with mild mitral regurgitation
Authors: Fujii Yoko , Wakao Yoshito 
Published: January 2006

AbstractObjective—To assess autonomic function in dogs with mild mitral regurgitation (MR) that did not have clinical signs of the condition.Animals—6 healthy adult Beagles.Procedure—Mild MR was experimentally induced. A 24-hour ambulatory ECG was recorded before and after induction of MR. Heart rate variability was analyzed in frequency domains by use of the ambulatory ECG. Low-frequency (LF) and high-frequency (HF) power were calculated by integrating over their frequency intervals, and the ratio of LF to HF was also calculated. Measurements of frequency domains were analyzed for 4 time periods (midnight to 6 AM, 6 AM to noon, noon to 6 PM, and 6 PM to midnight).Results—Dogs with experimentally induced MR were classified as International Small Animal Cardiac Health Council class Ia. The HF power of dogs with MR was significantly decreased between 6 AM and noon. The ratio of LF to HF in dogs with MR was significantly increased for the periods between midnight and 6 AM, 6 AM and noon, and noon and 6 PM.Conclusions and Clinical Relevance—Compensatory response through autonomic modulation was observed in dogs with mild MR that did not have abnormalities, except for cardiac murmur, during clinical examination. This result suggests that treatment during the early stages of mild MR may be beneficial. Additional studies are necessary to determine whether such treatment will delay the onset of congestive heart failure and prolong survival in dogs affected with mild MR. (Am J Vet Res2003; 64:145–148)
Detection of biofilm formation and nanobacteria under long-term cell culture conditions in serum samples of cattle, goats, cats, and dogs
Authors: Barr Stephen C. , Linke Rebecca A. , Janssen Dorothee , Guard Charles L. , Smith Mary C. , Daugherty Carole S. , Scarlett Janet M. 
Published: January 2006

Abstract

Objective—To determine the prevalence of biofilm
formation under long-term cell culture conditions in
serum samples of dairy cattle, goats, cats, and dogs,
and to determine whether there is an association
between nanobacteria and biofilm formation.

Sample Population—Serum samples of clinically
normal animals (313 dairy cattle, 48 goats, 140 dogs,
and 44 cats) and animals with various medical conditions
(60 dogs and 116 cats).

Procedure—Serum was incubated under cell culture
conditions and observed for biofilm formation by use
of light microscopy, electron microscopy, and spectroscopy.
A polymerase chain reaction assay was
developed to identify 16S rRNA gene sequences of
nanobacteria.

Results—Biofilm formation developed in serum samples
of 304 of 313 (97%) cattle, 44 of 48 (92%) goats,
44 of 44 (100%) cats, and 126 of 140 (90%) dogs.
Prevalence of serum samples with positive results for
biofilm formation was not significantly different
between cats or dogs with and without medical conditions
associated with pathologic extraskeletal calcification
processes. Scanning electron microscopy and
spectroscopy of biofilm samples revealed small coccoid
particles consisting mainly of calcium and phosphate.
Polymerase chain reaction assay failed to
amplify sequences of nanobacteria.

Conclusions and Clinical Relevance—Under longterm
cell culture conditions, biofilm made up of aggregates
of calcium and phosphate crystals does form in
serum samples of clinically normal dairy cattle, goats,
cats, and dogs. Disease, however, does not predispose
to biofilm formation in serum samples of dogs
and cats. Our findings did not support the existence
of nanobacteria in serum samples of cattle, goats,
cats, and dogs. (Am J Vet Res 2003;64:176–182)
Use of threshold serum and milk ketone concentrations to identify risk for ketosis and endometritis in high-yielding dairy cows
Authors: Reist Martin , Erdin Daniel K. , von Euw Daniel , Tschümperlin Kaspar M. , Leuenberger Hans , Hammon Harald M. , Künzi Niklaus , Blum Jürg W. 
Published: January 2006

AbstractObjective—To use threshold concentrations of acetone and β-hydroxybutyrate in milk and serum, respectively; identify risk for ketosis and endometritis; and assess analyses of blood and milk samples as predictors of risk for ketosis in high-yielding dairy cows.Animals—90 multiparous Holstein cows.Procedure—At intervals before and after parturition, blood samples were obtained for determination of glucose, nonesterified fatty acids, leptin, insulin, insulin-like growth factor-1, and β-hydroxybutyrate concentrations. Samples of milk were obtained at similar intervals after parturition for determination of fat content and concentrations of acetone, protein, and lactose. Reproductive examination of each cow was performed weekly.Results—For each cow, threshold concentrations of acetone and β-hydroxybutyrate were calculated as 75th and 90th percentiles of maximum postpartum concentrations of acetone in milk (0.40 and 0.87 mmol/L) and β-hydroxybutyrate in serum (2.30 and 3.51 mmol/L). Significant decrease in milk production (442 to 654 kg of energy-corrected milk/305-day period per cow) was associated with acetone or β-hydroxybutyrate in excess of threshold values. Milk acetone concentrations > 0.40 mmol/L were associated with 3.2 times higher risk for endometritis. Low plasma glucose, high serum β-hydroxybutyrate, and high milk acetone concentrations during week 1 after parturition were indicators of increased risk for ketosis later during lactation.Conclusions and Clinical Relevance—Determination of milk acetone concentration during the week after parturition may identify cows at risk for ketosis and endometritis; with appropriate interventions, development of disease and production losses may be reduced. (Am J Vet Res2003:64:188–194)
Description of an epidemic simulation model for use in evaluating strategies to control an outbreak of foot-and-mouth disease
Authors: Bates Thomas W. , Thurmond Mark C. , Carpenter Tim E. 
Published: January 2006

Abstract

Objective—To develop a spatial epidemic model to
simulate intraherd and interherd transmission of footand-
mouth disease (FMD) virus.

Sample Population—2,238 herds, representing
beef, dairy, swine, goats, and sheep, and 5 sale yards
located in Fresno, Kings, and Tulare counties of
California.

Procedure—Using Monte-Carlo simulations, a spatial
stochastic epidemic simulation model was developed
to identify new herds that would acquire FMD following
random selection of an index herd and to assess
progression of an epidemic after implementation of
mandatory control strategies.

Results—The model included species-specific transition
periods for FMD infection, locations of herds,
rates of direct and indirect contacts among herds, and
probability distributions derived from expert opinions
on probabilities of transmission by direct and indirect
contact, as well as reduction in contact following
implementation of restrictions on movements in designated
infected areas and surveillance zones.
Models of supplemental control programs included
slaughter of all animals within a specified distance of
infected herds, slaughter of only high-risk animals
identified by use of a model simulation, and vaccination
of all animals within a 5- to 50-km radius of infected
herds.

Conclusions and Clinical Relevance—The FMD
model represents a tool for use in planning biosecurity
and emergency-response programs and in comparing
potential benefits of various strategies for control
and eradication of FMD appropriate for specific populations.
(Am J Vet Res 2003;64:195–204)
Diagnostic value of the use of lateral and occlusal radiographic views in comparison with periodontal probing for the assessment of periodontal attachment of the canine teeth in dogs
Authors: Tsugawa Anson J. , Verstraete Frank J. M. , Kass Philip H. , Görrel Cecilia 
Published: January 2006

AbstractObjective—To determine the diagnostic value of 2 intraoral bisecting angle radiographic views in comparison with periodontal probing for the assessment of periodontal attachment of the canine teeth in dogs.Study Population—466 canine teeth from 117 dogs.Procedure—Periodontal probing measurements were recorded, and clinical attachment levels (CAL) were calculated at the mesial, buccal, distal, and lingual (or palatal) surfaces on each canine tooth. Occlusal and lateral radiographs of the canine teeth were obtained. Alveolar margin height (AMH) was measured at the same 4 surfaces. Values for AMH and CAL were compared on the basis of tooth surface, dental arch, and radiographic view.Results—The AMH at the mesial and distal surfaces of the mandibular canine teeth was measurable on the lateral view and was significantly correlated with CAL. Similar results were found for the mesial and distal surfaces of the maxillary canine teeth. Buccal and lingual AMH were measured on the mandibular occlusal radiographic view, and values were significantly correlated with CAL, but only the buccal AMH could be assessed on the occlusal radiographic view of the maxilla with values that correlated significantly with CAL.Conclusions and Clinical Relevance—The lateral radiographic view is suitable for evaluating periodontal attachment at the mesial and distal surfaces of the canine teeth in dogs. The occlusal radiographic view is suitable for assessing buccal surfaces as well as the lingual surface of mandibular canine teeth but not the palatal surface of maxillary canine teeth in dogs. (Am J Vet Res2003;64:255–261)
Relationship of age, sex, body weight, and hematologic and respiratory variables with airway reactivity in adult cats
Authors: Hirt Reinhard A. , Dederichs Diana , Boehler Alexandra , Hoffman Andrew M. 
Published: January 2006

AbstractObjective—To evaluate the association between airway reactivity and age, sex, body weight, and radiographic findings in cats.Animals—32 mature cats that constituted 2 age groups (17 young cats that were 1 to 2 years old and 15 old cats that were 12 to 13 years old).Procedure—Cats were placed in the chamber of a barometric whole-body plethysmograph (volume, 38 L), and box pressure was measured at baseline and after aerosol administration of increasing concentrations of carbachol. Airway reactivity was assessed by monitoring increases in enhanced pause (PENH), a unitless variable that measures bronchoconstriction as derived from dose-response curves. The endpoint chosen was the provocative concentration of carbachol that increased PENH to 300% of the baseline value (PCPENH300).Results—We did not find a correlation between PCPENH300 and sex, body weight, number of eosinophils, PENH before bronchoconstriction, respiratory frequency, tidal volume, or minute ventilation. Airway reactivity was significantly less in the old cats (mean ± SD PCPENH300, 0.578 ± 0.051%), compared with the value for the young cats (0.053 ± 0.006%). Radiographic patterns differed significantly between groups of cats; a greater proportion of old cats (12/15) had bronchointerstitial patterns, compared with the proportion of young cats (4/17).Conclusion and Clinical Relevance—These data support the notion that age exerts a strong influence on airway reactivity in adult cats, and radiographic differences suggest that structural changes in older cats may contribute to this effect. These findings have important implications for interpretation of results of airway reactivity tests in cats. (Am J Vet Res2003;64:26–31)
Expression of the ether-a-go-go (ERG) potassium channel in smooth muscle of the equine gastrointestinal tract and influence on activity of jejunal smooth muscle
Authors: Lillich James D. , Rakestraw Peter C. , Roussel Allen J. , Finley Melissa R. , Ganta Suhasini , Freeman Lisa C. 
Published: January 2006

AbstractObjective—To determine whether ether-a-go-go (ERG) potassium channels are expressed in equine gastrointestinal smooth muscle, whether ERG channel antagonists affect jejunal muscle contraction in vitro, and whether plasma cisapride concentrations in horses administered treatment for postoperative ileus (POI) are consistent with ERG channels as drug targets.Sample Population—Samples of intestinal smooth muscle obtained from 8 horses free of gastrointestinal tract disease and plasma samples obtained from 3 horses administered cisapride for treatment of POI.Procedure—Membranes were prepared from the seromuscular layer of the duodenum, jejunum, ileum, cecum, large colon, and small colon. Immunoblotting was used to identify the ERG channel protein. Isolated jejunal muscle strips were used for isometric stress response to ERG channel blockers that included E-4031, MK-499, clofilium, and cisapride. Plasma concentrations of cisapride were determined in 3 horses administered cisapride for treatment of POI after small intestinal surgery.Results—Immunoblotting identified ERG protein in all analyzed segments of the intestinal tract in all horses. The selective ERG antagonist E-4031 caused a concentration- dependent increase in jejunal contraction. Clofilium, MK-499, and cisapride also increased jejunal contraction at concentrations consistent with ERG channel block; effects of E-4031 and cisapride were not additive. Peak plasma cisapride concentrations in treated horses were consistent with ERG block as a mechanism of drug action.Conclusions and Clinical Relevance—The ERG potassium channels modulate motility of intestinal muscles in horses and may be a target for drugs. This finding may influence development of new prokinetic agents and impact treatment of horses with POI. (Am J Vet Res2003;64:267–272)
Evaluation of systemic immunologic hyperreactivity after intradermal testing in horses with chronic laminitis
Authors: Wagner Ilka P. , Rees Christine A. , Dunstan Robert W. , Credille Kelly M. , Hood David M. 
Published: January 2006

AbstractObjective—To determine whether systemic immunologic hyperreactivity exists in horses with chronic laminitis, compared with responses for nonlaminitic horses.Animals—7 nonlaminitic horses and 7 CL horses.Procedure—In experiment 1, intradermal testing (IDT) was performed on 7 nonlaminitic and 7 CL horses to evaluate the response to a combination of 70 allergens at 15 and 30 minutes and 4 and 24 hours after injection. Three nonlaminitic and 3 CL horses used in experiment 1 were used in experiment 2 to determine whether histologic differences existed between the 2 groups. The H&E-stained tissue sections were evaluated on the basis of 3 criteria. For all analyses, 2-samplet-tests were used to determine significant differences between the groups.Results—In experiment 1, CL horses had significantly higher total responses to IDT than nonlaminitic horses at the first 3 time periods. Also, CL horses had significantly fewer total scores of 0 than nonlaminitic horses at all time periods, except at 24 hours. In experiment 2, we did not detect significant differences between groups for any criterion.Conclusions and Clinical Relevance—Results support the hypothesis that CL horses develop hyperreactivity to various antigenic stimuli, compared with responses for nonlaminitic horses. Therefore, the possibility that antigenic challenge may result in exacerbation of clinical signs of laminitis should be discussed with horse owners. Chronic laminitis should also be a consideration when a horse becomes lame following antigenic challenges. (Am J Vet Res2003;64:279–283)
Effect of immunization with bovine luteinizing hormone receptor on ovarian function in cats
Authors: Saxena Brij B. , Clavio Abbie , Singh Mukul , Rathnam Premila , Bukharovich E. Yaroslaw , Reimers Thomas J. , Saxena Anjali , Perkins Scott 
Published: January 2006

AbstractObjective—To determine the effect of immunization with bovine luteinizing hormone receptor (LH-R) on ovarian function of cats.Animals—9 adult female domestic cats.Procedure—7 cats were immunized with 0.5 mg of LH-R encapsulated in a silastic subdermal implant (3 × 10 mm); 2 served as control cats. Receptors had 80% specific binding to125I-human chorionic gonadotropin with a binding capacity of 2,682 pM/mg. Cats received booster injections of LH-R. Cats were induced to ovulate with luteinizing hormone (LH) releasing hormone on day 345. Samples of venous blood and vaginal cells were collected through day 395. Observation of estrus behavior continued until day 516. Serum concentrations of estradiol, progesterone, thyroid gland hormones, LH, and LH-R antibody were determined.Results—LH-R antibody was detected in the sera of immunized cats within 21 days after implantation. Detection of LH-R antibody was associated with suppression of serum progesterone to ≤ 0.5 ng/mL during the study period, compared with concentrations of 5 to 10 ng/mL in control cats. Immunized cats did not display signs of estrus. Release of LH after administration of LH releasing hormone indicated an intact hypothalamic-pituitary axis but poor corpus luteum function. Serum estradiol concentrations remained between 30 to 40 pg/mL in immunized and control cats. With the decrease antibody titers, hormone concentrations returned to a pattern consistent with that during fertility.Conclusions and Clinical Relevance—Active immunization with LH-R suppressed corpus luteum function in cats. The effect was reversible. An LH-R-based antifertility vaccine may have clinical application in other vertebrates. (Am J Vet Res2003;64:292–298)