bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ultrastructural changes in follicles of small-intestinal aggregated lymphoid nodules in early and advanced phases of experimentally induced mucosal disease in calves
Authors: Teichmann Ulrike , Liebler-Tenorio Elisabeth M. , Pohlenz Joachim F. 
Published: December 2005

AbstractObjective—To investigate ultrastructural changes in follicles of small-intestinal aggregated lymphoid nodules (Peyer's patches) of calves with early and advanced phases of experimentally induced mucosal disease (MD).Animals—Twenty 2.5- to 7-month-old Holstein-Friesian calves (11 females, 9 males).Procedure—MD was induced in 13 of 18 calves that were persistently viremic with bovine viral diarrhea virus (BVDV). Eight of the 13 calves were euthanatized before the onset of clinical signs of MD, and 5 were euthanatized after becoming moribund with MD. Five persistently viremic calves and 2 calves without BVDV served as controls. Specimens of small-intestinal aggregated lymphoid nodules were prepared for transmission electron microscopy.Results—The ultrastructure of follicles of smallintestinal aggregated lymphoid nodules from healthy calves was consistent with that in sheep. In the early phase of MD, changes were characterized by numerous apoptotic lymphocytes and macrophages with apoptotic bodies. In more advanced lesions, affected lymphoid follicles consisted of macrophages and variable numbers of follicular dendritic cells (FDC), whereas others did not contain FDC. In moribund calves, small follicles consisting predominantly of FDC and follicles with central cavities surrounded by macrophages, and few neutrophils were observed.Conclusions and Clinical Relevance—The ultrastructural changes in lymphoid follicles of smallintestinal aggregated lymphoid nodules indicate apoptosis of lymphocytes as an initial event. The development of small follicles consisting predominantly of FDC or the complete loss of follicular architecture in advanced phases of MD is determined by the intensity of apoptosis of lymphocytes, the capacity of the macrophages for uptake, and the reorganization of a stromal network. (Am J Vet Res2000;61:174–182)
Structure-related echoes in ultrasonographic images of equine superficial digital flexor tendons
Authors: Schie Hans T. M. van , Bakker E. M. 
Published: December 2005

AbstractObjective—To develop a method to discriminate between structure-related echoes and echoes resulting from interference, as observed in transverse ultrasonographic images of equine superficial digital flexor (SDF) tendons.Sample Population—2 normal (injury-free) SDF tendons obtained from a 3-year-old Thoroughbred and a 9-year-old Dutch Warmblood horse.Procedure—Tendons were mounted in a custommade device that permitted exact transverse and perpendicular sequential scanning with precise steps of 0.5 mm along the long axis of the tendon. Photographs of ultrasonographic images of transverse tendon sections at the exact scanning locations were obtained. Propagation, reflection, and refraction artifacts were quantified, and an image rectification procedure was developed, allowing exact matching of each photograph with the corresponding ultrasonographic image. A correlation routine was developed that departed from this transverse ultrasonographic image (position 0); this routine added information from images collected at precise distances of 0.5 and 1 mm on both sides of the actual scan location (positions –2, –1, +1, +2).Results—By use of the correlation routine, echoes that remained steady over all 5 images were enhanced and resolved, and constantly changing echoes were multiplicatively reduced and faded. This correlated image could be projected over the rectified photograph, and the resolved echoes matched perfectly with the endotendon septa surrounding fibers and fasciculi.Conclusions and Clinical Relevance—The correlation routine permits exclusive resolution of structurerelated echoes, as echoes resulting from interference are faded. The technique described can produce images that depict only the essential structure-related information. In this way, the clinical assessment of tendon integrity is greatly facilitated. (Am J Vet Res1999;60:202–209)
Ultrasonographic tissue characterization of equine superficial digital flexor tendons by means of gray level statistics
Authors: Schie Hans T. M. van , Bakker E. M. , Jonker A. M. , Weeren P. R. van 
Published: December 2005

AbstractObjective—To correlate quantitative analysis of ultrasonographic images of normal (injury-free) equine superficial digital flexor (SDF) tendons and equine SFD tendons that have pathologic changes with corresponding histologic sections.Sample Population—4 SDF tendons, 2 of which had various stages of tissue integrity. The 2 ipsilateral tendons were used as points of reference.Procedure—Tendons were mounted in a custommade device that permitted sequential scanning, transversely and perpendicular to the tendon long axis. At precise steps of 0.5 mm, transverse ultrasonographic images were collected. Subsequently, tendons were fixed and prepared for histologic examination. The following 8 tissue types were discerned: normal young, normal old, necrotic, early granulation, late granulation, early fibrotic, late fibrotic, and scar tissues. In areas of interest, the corresponding ultrasonographic images were selected for gray level statistical analysis.Results—Compared with other tissue types, earlystage granulation tissue was characterized by substantially lower mean gray level and a clearly different histogram. Necrotic tissue had a higher mean gray level, with a virtually normal histogram. In late granulation and early fibrotic tissues, the mean gray level and the histogram could not be discerned from those of normal tendon tissue. The same applied to late fibrotic and scar tissues; mean gray levels were fractionally lower than those of normal tendon tissue with a completely normal histogram.Conclusions—Although quantification of the transverse ultrasonographic image by use of first-order gray level statistics may be helpful, the method is not sufficiently sensitive to accurately and unequivocally determine the type of tendon tissue. Quantitative analysis should incorporate transverse and longitudinal information. (Am J Vet Res2000;61: 210–219)
Calcium regulation by skeletal muscle membranes of horses with recurrent exertional rhabdomyolysis
Authors: Ward Tara L. , Valberg Stephanie J. , Gallant Esther M. , Mickelson James R. 
Published: December 2005

AbstractObjective—To determine whether an alteration in calcium regulation by skeletal muscle sarcoplasmic reticulum, similar to known defects that cause malignant hyperthermia (MH), could be identified in membrane vesicles isolated from the muscles of Thoroughbreds with recurrent exertional rhabdomyolysis (RER).Sample Population—Muscle biopsy specimens from 6 Thoroughbreds with RER and 6 healthy (control) horses.Procedures—RER was diagnosed on the basis of a history of > 3 episodes of exertional rhabdomyolysis confirmed by increases in serum creatine kinase (CK) activity. Skeletal muscle membrane vesicles, prepared by differential centrifugation of muscle tissue homogenates obtained from the horses, were characterized for sarcoplasmic reticulum (SR) activities, including the Ca2+release rate for the ryanodine receptor-Ca2+release channel, [3H]ryanodine binding activities, and rate of SR Ca2+-ATPase activity and its activation by Ca2+.Results—Time course of SR Ca2+-induced Ca2+release and [3H]ryanodine binding to the ryanodine receptor after incubation with varying concentrations of ryanodine, caffeine, and ionized calcium did not differ between muscle membranes obtained from control and RER horses. Furthermore, the maximal rate of SR Ca2+-ATPase activity and its affinity for Ca2+did not differ between muscle membranes from control horses and horses with RER.Conclusions and Clinical Relevance—Despite clinical and physiologic similarities between RER and MH, we concluded that RER in Thoroughbreds does not resemble the SR ryanodine receptor defect responsible for MH and may represent a novel defect in muscle excitation-contraction coupling, calcium regulation, or contractility. (Am J Vet Res2000;61:242–247)
Respiratory reflexes in response to nasal administration of halothane to anesthetized, spontaneously breathing dogs
Authors: Mutoh Tatsushi , Kanamaru Arata , Tsubone Hirokazu , Nishimura Ryohei , Sasaki Nobuo 
Published: December 2005

AbstractObjective—To characterize and determine the sensory innervation of respiratory reflexes elicited by nasal administration of halothane to dogs.Animals—10 healthy Beagles.Procedure—Dogs underwent permanent tracheostomy and, 2 to 3 weeks later, were anesthetized with thiopental and α-chloralose administered IV. The nasal passages were functionally isolated so that halothane could be administered to the nasal passages while dogs were breathing 100% O2via the tracheostomy. Respiratory reflexes in response to administration of halothane at concentrations of 1.25, 1.75, and 2.5 times the minimum alveolar concentration (MAC), and 5% (administered in 100% O2at a flow rate of 5 L/min) were recorded. Reflexes in response to administration of 5% halothane were also recorded following transection of the infraorbital nerve, transection of the caudal nasal nerve, and nasal administration of lidocaine.Results—Nasal administration of halothane induced an inhibition of breathing characterized by a dosedependent increase in expiratory time and a resultant decrease in expired volume per unit time. Effects were noticeable immediately after the onset of halothane administration and lasted until its cessation. Reflex responses to halothane administration were attenuated by transection of the caudal nasal nerve and by nasal administration of lidocaine, but transection of the infraorbital nerve had no effect.Conclusions and Clinical Relevance—Nasal administration of halothane at concentrations generally used for mask induction of anesthesia induces reflex inhibition of breathing. Afferent fibers in the caudal nasal nerve appear to play an important role in the reflex inhibition of breathing induced by halothane administration. (Am J Vet Res2000;61:260–267)
Histomorphometric analysis of the proximal portion of the femur in healthy dogs
Authors: Edinger David T. , Hayashi Kei , Hongyu Yao , Markel Mark D. , Manley Paul A. 
Published: December 2005

Abstract

Objective—To describe the cancellous bone architecture
of the head and neck of the femur in healthy
dogs by use of automated histomorphometry techniques
in conjunction with histologic grading of articular
cartilage.

Animals—30 mature male dogs with healthy coxofemoral
joints

Procedure—Dogs were 1.5 to 4 years old and
weighed 27 to 37 kg. Computer images of fine-detail
radiographs of 100-µm-thick coronal and transverse
plane sections of the head and neck of the femur
(14 dogs) were analyzed by use of histomorphometry
software. Statistical comparisons among histomorphometric
indices of 4 regions were performed.
Histologic preparations of coronal and transverse
plane sections of femoral head articular cartilage
(16 dogs) were graded. Median grades for lateral,
medial, cranial, and caudal halves of the femoral head
articular cartilage were determined.

Results—Bone volume/total volume, trabecular thickness
and number, and bone surface/total volume were
significantly higher in the femoral head than in the
femoral neck. Anisotropy (trabecular alignment) and
trabecular separation were significantly higher in the
femoral neck than in the femoral head. Anisotropy was
significantly higher in the caudal half of the femoral
neck than in the cranial half. Cartilage had histologic
grades indicating health without significant differences
among lateral, medial, cranial, and caudal halves of
femoral head cartilage.

Conclusions and Clinical Relevance—A predictable
cancellous architecture in the head and neck of the
femur is associated with healthy cartilage. (Am J Vet
Res 2000;61:268–274)
Effect of sample number and time on determination of plasma clearance of technetium Tc 99m pentetate and orthoiodohippurate sodium I 131 in dogs and cats
Authors: Barthez Paul Y. , Chew Dennis J. , DiBartola Stephen P. 
Published: December 2005

AbstractObjective—To determine the effect of number of blood samples and sampling times on plasma clearance of technetium Tc 99m pentetate (Tc99mP) and orthoiodohippurate sodium I 131(OIH).Animals—20 dogs and 14 cats.Procedure—Plasma clearances of OIH and Tc99mP were calculated by use of a 2-compartment model, on the basis of a 12-point curve as a reference method. Plasma clearance was calculated by use of all possible combinations of 4 to 11 samples. Time schedule yielding the smallest difference from the reference method was considered to be optimal. Regression analysis was performed between the 12-point model and models using a reduced number of samples.Results—SD of the difference between the 12-point clearance and the models with reduced numbers of samples increased when the number of samples decreased. The SD of the difference between 12-point clearance and 4-point clearance was 4.17 ml/min for OIH and 0.94 ml/min for Tc99mP in dogs and 0.45 ml/min for OIH and 0.11 ml/min for Tc99mP in cats. Optimal schedules were distributed logarithmically and included an early sample at 5 or 10 minutes, a late sample at 2.5, 3, 4, or 5 hours for OIH, and a late sample at 4 or 5 hours for Tc99mP.Conclusions and Clinical Relevance—Plasma clearances of OIH and Tc99mP can be accurately calculated in dogs and cats by use of a single-injection 2-compartment pharmacologic model with a reduced number of blood samples, resulting in an acceptable margin of error. (Am J Vet Res2000;61:280–285)
Comparison of nuclear scintigraphy and acetaminophen absorption as a means of studying gastric emptying in horses
Authors: Lohmann Katharina L. , Roussel Allen J. , Cohen Noah D. , Boothe Dawn M. , Rakestraw Peter C. , Walker Michael A. 
Published: December 2005

AbstractObjective—To evaluate the correlation between halftime of liquid-phase gastric emptying (T50), determined with nuclear scintigraphy using technetium Tc 99m pentetate, and absorption variables of orally administered acetaminophen.Animals—6 mature horses.Procedure—Technetium Tc 99m pentetate (10 mCi) and acetaminophen (20 mg/kg of body weight) were administered simultaneously in 200 ml of water. Serial left and right lateral images of the stomach region were obtained with a gamma camera, and T50determined separately for counts obtained from the left side, the right side and the geometric mean. Power exponential curves were used for estimation of T50 and modified R2 values for estimation of goodness of fit of the data. Serial serum samples were taken, and acetaminophen concentration was determined, using fluorescence polarization immunoassay. Maximum serum concentration (Cmax), time to reach maximum serum concentration (Tmax), area under the curve for 240 minutes and the absorption constant (Ka) were determined, using a parameter estimation program. Correlations were calculated, using the Spearman rank correlation coefficient.Results—Correlations between T50and Tmaxand between T50and Kawere significant.Conclusions and Clinical Relevance—Tmaxand Kaare valuable variables in the assessment of liquidphase gastric emptying using acetaminophen absorption. Acetaminophen absorption may be a valuable alternative to nuclear scintigraphy in the determination of gastric emptying rates in equine patients with normally functioning small intestine. (Am J Vet Res2000;61:310–315)
Comparison of polymerase chain reaction assays with bacteriologic culture, immunofluorescence, and nucleic acid hybridization for detection of Leptospira borgpetersenii serovar hardjo in urine of cattle
Authors: Wagenaar Jaap , Zuerner Richard L. , Alt David , Bolin Carole A. 
Published: December 2005

AbstractObjective—To compare sensitivity and specificity of various polymerase chain reaction (PCR) assays for detection ofLeptospira borgpeterseniiserovarhardjoin bovine urine and to compare results of the optimal PCR assay with results of immunofluorescence, nucleic acid hybridization, and bacteriologic culture.Animals—6 heifers.Procedure—Heifers were exposed to serovar hardjo type hardjo-bovis by conjunctival instillation of 106leptospires on 3 successive days. Urine samples were collected before and after infection. Sensitivity and specificity of 5 PCR assays were compared, to determine the optimal assay for use with bovine urine samples. The optimal PCR assay was then compared with results of bacteriologic culture, nucleic acid hybridization, and immunofluorescence.Results—A PCR assay with the best combination of specificity (100%) and sensitivity (91%) was selected for comparison with the other diagnostic tests. Sensitivity for nucleic acid hybridization was 55%, whereas sensitivity for bacteriologic culture and immunofluorescence was 89 to 93%.Conclusions and Clinical Relevance—Bacteriologic culture, PCR, and immunofluorescence were sensitive for detection ofL borgpeterseniiserovarhardjotype hardjo-bovis in urine specimens of cattle, but a single technique was not the most sensitive for each animal tested. Therefore, the use of 2 techniques in combination is warranted for maximal sensitivity for diagnosis. (Am J Vet Res2000;61:316–320)
Comparison of equine amnion and a nonadherent wound dressing material for bandaging pinch-grafted wounds in ponies
Authors: Goodrich Laurie R. , Moll H. David , Crisman Mark V. , Lessard Pierre , Bigbie Rocky B. 
Published: December 2005

AbstractObjective—To evaluate healing of pinch-grafted wounds on the distal aspect of the limbs of ponies bandaged with equine amnion or a standard nonadherent wound dressing material.Animals—6 ponies.Procedure—A 2.5 × 2.5-cm full-thickness section of skin was removed from the dorsal aspect of each limb at the midpoint of the metacarpus or metatarsus. Six days later, wounds were grafted with partial-thickness pinch grafts. Half the wounds were bandaged with amnion, and the other half were bandaged with a nonadherent dressing. Bandages were changed every 3 days until wound healing was complete. At each bandage change, numbers of grafts lost were recorded, and wounds were measured.Results—Percentage of grafts lost from wounds bandaged with amnion was not significantly different from percentage lost from wounds bandaged with the nonadherent dressing. Median healing time for wounds bandaged with amnion (30 days) was significantly less than median healing time for wounds bandaged with the nonadherent dressing (39 days). All wounds were healed by day 45.Conclusions and Clinical Relevance—Results suggest that amnion can be used for bandaging pinchgrafted wounds on the distal aspect of the limbs of ponies. (Am J Vet Res2000;61:326–329)
Immune function of bovine leukocytes after in vitro exposure to selected heavy metals
Authors: Guise Sylvain De , Bernier Jacques , Lapierre Patrice , Dufresne Marc M. , Dubreuil Pascal , Fournier Michel 
Published: December 2005

Abstract

Objective—To study effects of in vitro exposure of
bovine leukocytes to mercury, cadmium, and lead on
phagocytosis, natural killer cell activity, and lymphocyte
proliferation.

Sample Population—Leukocytes from 6 nonpregnant
Holstein heifers.

Procedure—Leukocytes were exposed in vitro to the
aforementioned metals, and leukocyte functions
were assessed.

Results—Phagocytosis was suppressed by 10−5 to
10−7
M CdCl2 and by 10−5 and 10−6
M HgCl2, but not
10−7
M HgCl2 nor 10−4 to 10−6
M PbCl2. Spontaneous and
concanavalin A- or phytohemagglutinin-stimulated proliferation
of metal-treated bovine blood mononuclear
cells was not significantly different from that of nontreated
control cells, except for enhanced spontaneous
proliferation in response to 10−5
M HgCl2. When proliferation
was expressed as a stimulation index, a dosedependent
increase of spontaneous proliferation was
observed in response to exposure to HgCl2 and PbCl2.
Compared with response to 10−6 or 10−7
M CdCl2, reduction
of mitogen-induced and spontaneous proliferation
was observed on exposure to 10−5
M CdCl2. Natural
killer cell activity against yeast artificial chromosome
target cells, evaluated by flow cytometry, was
decreased only in cells exposed to 10−5
M HgCl2.

Conclusion and Clinical Relevance—Bovine leukocytes
are susceptible to the immunomodulatory
effects of in vitro exposure to heavy metals at concentrations
equal to or higher than those at which similar
effects are seen for leukocytes from most other animal
species for which data are available for comparison.
Exception is phagocytosis, which is severely affected
by low concentrations of CdCl2 and HgCl2 in cattle.
Reduction of defense mechanisms on exposure to
metals could lead to increased susceptibility to potential
pathogens.(Am J Vet Res 2000;61:339–344)
Intracellular microelectrode recording to characterize inhibitory neuromuscular transmission in jejunum of horses
Authors: Rakestraw Peter C. , Snyder Jack R. , Sanders Kenton M. , Shuttleworth William C. 
Published: December 2005

AbstractObjective—To evaluate electrical activity of jejunal circular muscle in horses and characterize electrical responses to stimulation by intrinsic inhibitory neurons.Sample Population—Portions of jejunum obtained from horses euthanatized for reasons other than gastrointestinal tract disease.Procedure—Isolated circular muscle preparations were perfused with oxygenated modified Krebs solution. Glass microelectrodes were used for intracellular recording of membrane potentials from single smooth muscle cells. Electrical activity and responses to electrical field stimulation (EFS) of intrinsic neurons in the presence of guanethidine and atropine were recorded. Mediators of responses to nerve stimulation were also evaluated, usingN-nitro-L-arginine methyl ester (L-NAME) and apamin.Results—Mean resting membrane potential (RMP) was 41.5 ± 1.8 mV. Small membrane potential oscillations were observed in muscle cells. Single or multiple action potentials were often superimposed on the peaks of these oscillations. Spontaneous oscillations and action potentials were blocked by nifedipine. Transient hyperpolarizations of smooth muscle cell membrane potentials (inhibitory junction potentials [IJP]) were observed in response to electrical field stimulation. The IJP evoked by stimulus trains consisted of an initial fast component followed by a slow component. The L-NAME did not have a significant effect on RMP and did not significantly affect the fast component of IJP at any stimulus frequency tested. In contrast, L-NAME abolished the slow component of IJP observed after trains of pulses. In the continued presence of L-NAME, apamin had no significant effect on RMP but effectively reduced the fast component of IJP.Conclusions and Clinical Relevance—Findings suggest that inhibitory neurotransmitters supplying equine jejunum act through different ionic mechanisms. Understanding these mechanisms may suggest new therapeutic targets for treatment of motility disorders. (Am J Vet Res2000;61:362–368)