bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microvascular permeability and endothelial cell morphology associated with low-flow ischemia/reperfusion injury in the equine jejunum
Authors: Dabareiner Robin M. , Snyder Jack R. , White Nathaniel A. , Pascoe John R. , Harmon Faye A. , Gardner Ian , Woliner Michael J. , Pinney Diane , Sullins K. E. 
Published: January 2024

SUMMARY
Microvascular permeability of the jejunum of clinically normal equids and microvascular permeability associated with 60 minutes of ischemia (25% baseline blood flow) and subsequent reperfusion were investigated. Eight adult horses were randomly allotted to 2 equal groups: normal and ischemic/reperfusion injury. Lymphatic flow rates, mesenteric blood flow, and lymph and plasma protein concentrations were determined at 15-minute intervals throughout the study. Microvascular permeability was determined by estimates of the osmotic reflection coefficient, which was determined when the ratio of lymphatic protein to plasma protein concentration reached a constant minimal value as lymph flow rate increased (filtration-independent lymph flow rate), which occurred at venous pressure of 30 mm of Hg. Full-thickness jejunal biopsy specimens were obtained at the beginning and end of each experiment, and were prepared for light microscopy to estimate tissue volume (edema) and for transmission electron microscopy to evaluate capillary endothelial cell morphology.
The osmotic reflection coefficient for normal equine jejunum was 0.19 ± 0.06, and increased significantly (P < 0.0001) to 0.48 ± 0.05 after the ische- mia/reperfusion period. Microscopic evaluation revealed a significant increase (P < 0.0001) in submucosal and serosal volume and capillary endothelial cell damage in horses that underwent ischemia/reperfusion injury. Results indicate that ischemia/re-perfusion of the equine jejunum caused a significant increase in microvascular permeability.
Ultrastructural study of unidentified inclusions in the cornea and iridocorneal angle of dogs with pannus
Authors: Rapp Eva , Kölbl Sylvia 
Published: January 2024

SUMMARY
The corneas and/or the iridocorneal angles of 13 dogs were examined morphologically by use of transmission electron microscopy. Virologic identification techniques also were used for tissue from 2 dogs. Four dogs had clinical signs of chronic superficial keratitis or pannus, 9 dogs had normal eyes.
In the tissue from 7 dogs (4 German Shepherd Dogs with chronic superficial keratitis; 2 German Shepherd Dogs and 1 mixed-breed dog with normal eyes) we found unusual cytoplasmic inclusions. Inclusions were not found in dogs of other breeds with normal eyes. The inclusions were observed in comeal fibroblasts, vascular endothelial cells, and macrophages, as well as in trabecular cells and fibroblasts of the iridocorneal angle. They were often grouped within the rough endoplasmic reticulum or found free in the cytoplasm. The cylindrical particles had a helical substructure, measuring 20 nm in diameter and up to 400 nm long, with a distance of 10 nm for the repeating turns.
Results of virologic culturing on canine and seal kidney cells were negative, as was staining with fluorescein isothiocyanate-labeled antibodies against canine distemper virus, canine herpesvirus, canine parvovirus, and canine adenovirus.
Relevance of the inclusion bodies described is discussed. Because our results seem to hint at a correlation between presence of the rod shaped particles and German Shepherd Dogs with pannus, we suggest that an etiologic or pathogenic connection exists that merits further examination.
Comparison of a radioimmunoassay (Charm II) test with high-performance liquid chromatography for detection of oxytetracycline residues in milk samples from lactating cattle
Authors: Moats William A. , Anderson Kevin L. , Rushing John E. , Wesen Donald P. 
Published: January 2024

SUMMARY
A radioimmunoassay test for tetracyclines (Charm II) was compared with high-pressure liquid chromatography (hplc) for detection of oxytetracycline (otc) residues in milk samples from individual lactating cows. Oxytetracycline was administered by 1 of 3 routes (IV, IM, or intrauterine) to 21 lactating dairy cows. A total of 292 duplicate milk samples were collected from milkings before and through 156 hours after otc administration. Concentration of otc in these samples was determined by use of the Charm II test and an hplc method with a lower limit of quantitation, approximately 2 ng of otc/ml. Samples were also classified with respect to presence of otc residues relative to the fda safe concentration (< 30 ng/ml), using the Charm II (by control point determination) and hplc methods.
There was a significant (P < 0.05) difference between test methods in classification of milk samples with respect to presence or absence of otc at the fda safe concentration. A total of 48 of the 292 test results (16.4%) did not agree. Using the hplc test results as the standard with which Charm II test results were compared, 47 false presumptive-violative test results and 1 false presumptive-nonviolative Charm fi test result (a sample containing 31 ng of otc/ml, as evaluated by hplc) were obtained. The samples with false presumptive-violative Charm fi results contained < 30 ng of otc/ml, as evaluated by hplc.
In some respects, the Charm H test performed appropriately as a screening test to detect otc residues in milk samples from individual cows. However, the tendency for the test to yield presumptive-violative test results at otc concentrations lower than the fda safe concentration (as evaluated by hplc), suggests that caution should be exercised in using the test as the sole basis on which a decision is made to reject milk. As indicated by the manufacturer, presumptive-violative Charm II test results should be confirmed by additional testing. Although not specifically evaluated, the tendency for misclassification of milk samples as presumptive-violative by the Charm II test may or may not occur in commingled milk, compared with milk samples from individual cows.
Evaluation of in vitro cytotoxicity of nonsteroidal anti-inflammatory drugs against canine tumor cells
Authors: Knapp Deborah W. , Chan Thomas C. K. , Kuczek Thomas , Reagan William J. , Park Beth 
Published: January 2024

SUMMARY
Piroxicam and other nonsteroidal anti-inflammatory drugs (nsaid) have antitumor activity against naturally acquired cancer in dogs and human beings, and against experimentally induced tumors in rodents. We are investigating potential mechanisms of nsaid antitumor activity. The direct cytotoxicity of piroxicam, indomethacin, and aspirin against 4 canine tumor cell lines (transitional cell carcinoma, squamous cell carcinoma, melanoma, and soft tissue sarcoma) was determined in short-term growth rate assays and in clonogenic assays. Piroxicam was evaluated alone and in combination with the lipoxygenase inhibitor zileuton, and in combination with the chemotherapeutic agents cisplatin and carboplatin. The 50% inhibitory concentrations (lC50) against melanoma cells in short-term growth rate assays were: 530 μM piroxicam, 180 μM indomethacin, and greater than 1 mM aspirin. These IC50 values were over 10 times greater than serum concentrations of these drugs that could safely be achieved in vivo. The IC50 of zileuton combined with piroxicam (280 μM) was not different from the IC50 of zileuton alone (230 μM; anova P = 0.47) in melanoma cells. Similarly, addition of piroxicam did not alter the IC50 of either cisplatin (1.6 μM) or carboplatin (6.1 μM). These results suggest that nsaid, at serum concentrations achievable in vivo, do not have direct cytotoxicity against canine tumor cells tested. It is unlikely that the in vivo antitumor activity of nsaid is attributable to a direct cytotoxic effect.
Comparison of the stride kinematics of the collected, medium, and extended walks in horses
Authors: Clayton Hilary Mary 
Published: January 2024

SUMMARY
Six horses, highly trained for dressage competition, were used to study the stride kinematics of the walk, and to compare the kinematics of the collected, medium, and extended walks. Horses were filmed in a sagittal plane at a rate of 150 frames/s; temporal, linear, and angular data were extracted from the films. Results of anova and Duncan's multiple range test indicated that the speed of the collected walk (1.37 m/s) was significantly (P < 0.01) slower than that of the medium (1.73 m/s) and extended (1.82 m/s) walks, values for which were not significantly different from each other. The increase in speed was associated with a significant increase in stride length, from 157 cm in the collected walk to 193 cm in the extended walk. This was a result of an increase in the over-tracking distance, whereas there was no significant difference in the distance between lateral placements of the limbs. Stride duration decreased (P < 0.01) from the collected walk (1,159 ms) to the extended walk (1,064 ms). Angles of the metacarpal and metatarsal segments, measured on the palmar/plantar aspect, were higher at impact and lower at lift off in the collected than in the extended walk (P < 0.01). This indicated greater range of angular motion of this segment during the stance phase in the extended walk. Only 1 of the 6 horses had a regular 4-beat rhythm of the footfalls, with equal time elapsing between the lateral and diagonal footfalls.
Colonization of the tonsils and nasopharynx of calves by a rifampicin-resistant Pasteurella haemolytica and its inhibition by vaccination
Authors: Frank Glynn H. , Briggs Robert E. , Zehr Emilie S. 
Published: January 2024

SUMMARY
A rifampicin-resistant Pasteurella haemolytica serotype 1 with 2 added plasmids was used as a colonization-challenge strain in calves to test the resistance to colonization elicited by vaccination. Nine calves were vaccinated with a tissue culture-derived P haemolytica serotype-1 vaccine which, in a prior study, had elicited a serotype-specific inhibition of nasal and tonsillar colonization by the homologous serotype under field conditions. The vaccinates and 9 nonvaccinated control calves were exposed by tonsillar instillation with the challenge strain. The P haemolytica were enumerated in nasal secretion and tonsil wash specimens collected biweekly for 3 weeks. Rifampicin-supplemented agar medium inhibited growth of other bacterial species in the specimens and, thus, increased the sensitivity of detection of the challenge P haemolytica by 100-fold. The challenge strain retained its plasmids during the period of colonization. Inhibition of colonization was evidenced by lower frequency of isolations and fewer isolations of the challenge strain from nasal secretion and tonsil wash specimens of the vaccinates than from those of the nonvaccinates.
Evaluation of health and ruminal variables during adaptation to grain-based diets in beef cattle
Authors: Leedle Jane A. Z. , Coe Michael L. , Frey Russell A. 
Published: January 2024

SUMMARY
Health and ruminal variables were intensively measured during adaptation to grain-based diets in 6 beef cattle with fistulated rumens. The cows had been maintained on prairie grass hay-supplemented diets, and were converted to a grain-based finishing ration by feeding each successive diet (diets 1-4, respectively) for a period of 7 days. Each cow was evaluated and samples were obtained 3 times each day for the first 5 days that each diet was fed. Health variables monitored were rectal temperature, pulse, respiratory and rumen motility rates, fecal consistency, demeanor, blood pH, and blood glucose and l(+) lactate concentrations. Ruminal variables monitored were pH and glucose, dl-lactate, and volatile fatty acid concentrations of rumen contents. Data were analyzed by use of a multivariate anova. We determined that most of the health variables were within reference range limits throughout the adaptation period; however, analysis of pulse and respiratory rates indicated that diets 2 and 4 were stressful. Although blood pH continually decreased during feeding of the 4 diets (7.38 to 7.30), blood l(+) lactate and glucose concentrations had large increases only within diet 4. The pH of ruminal contents decreased progressively from 6.8 to 5.3. Rumen glucose concentration was low (< 1 μmol/ml), except with diet 4 in which values were 8 times higher than for other diets. By the end of the study, the ruminal contents of all animals were acidic (pH < 5.5), and, on the basis of higher than background amounts of ruminal glucose and dl-lactate, it was determined that rumen microbial equilibrium had not yet been achieved. Analysis of results of this study suggested that ruminal imbalance could be evaluated by monitoring pulse and respiratory rates, blood pH, and blood glucose concentrations.Assessment of the rumen alone could be accomplished by monitoring the variables of rumen pH, rumen glucose, and dl-lactate concentrations. Respiratory rate, blood and rumen content pH, and blood l(+) lactate concentrations were significantly (P < 0.001) affected by time after feeding.
Subcellular biochemical changes during the development of the small intestine of pony foals
Authors: Batt R. M. , Burgess D. , Edwards G. B. , van de Waal S. , Sørensen S. H. , Hart C. A. 
Published: January 2024

SUMMARY
To examine the postnatal development of equine small intestine, biopsy specimens of jejunal mucosa from 8 ponies, between 6 and 28 weeks old, were subjected to analytical subcellular fractionation and assay organelle marker enzymes. Fractionation revealed a reduction in the particulate brush border component of β-galactosidase (lactase) activity between 6 and 28 weeks, and a corresponding increase in soluble activity, although the reduction in mean specific activity was not significant. There also was a decrease in the proportion of brush border to soluble aminopeptidase N activity, a relative loss of brush border γ-glutamyltransferase and a considerable decrease the specific activity of alkaline phosphatase throughout the gradient fractions. In contrast, there were marked increases in activities α-glucosidase (maltase) and sucrase in the older ponies, accompanied by considerable changes in the intracellular distribution of particulate α-glucosidase activity, which was predominantly associated with endoplasmic reticulum at 6 weeks, whereas the large increase in activity observed by 28 weeks was clearly associated with the brush border. The modal density brush borders also increased with age, suggestive of an increase in the glycoprotein-to-lipid ratio of the microvillar membrane. In contrast to these brush border changes, there was relatively little alteration in the activities or density distributions of marker enzymes for endoplasmic reticulum, basolateral membranes, mitochondria, or lysosomes. These findings indicate that maturation of equine intestinal epithelium during the first few months of life results in major changes in the properties and enzyme composition of enterocyte brush borders.
Evaluation of pulmonary function and analgesia in dogs after intercostal thoracotomy and use of morphine administered intramuscularly or intrapleurally and bupivacaine administered intrapleurally
Authors: Stobie Daniel , Caywood Dennis D. , Rozanski Elizabeth A. , Bing Dennis R. , Dhokarikar Pradnya , Raffe Marc R. , Kannan Mathur S. , King Vickie L. , Hegstad Rebecca L. , Randall Debbie A. 
Published: January 2024

SUMMARY
Eighteen dogs undergoing lateral thoracotomy at the left fifth intercostal space were randomly assigned to 1 of 3 postoperative analgesic treatment groups of 6 dogs each as follows: group A, morphine, 1.0 mg/kg of body weight, im; group B, 0.5% bupivacaine, 1.5 mg/kg given interpleurally; and group C, morphine, 1.0 mg/kg given interpleurally. Heart rate, respiratory rate, arterial blood pressure, arterial blood gas tensions, alveolar-arterial oxygen differences, rectal temperature, pain score, and pulmonary mechanics were recorded hourly for the first 8 hours after surgery, and at postoperative hours 12, 24, and 48. These values were compared with preoperative (control) values for each dog. Serum morphine and cortisol concentrations were measured at 10, 20, and 30 minutes, hours 1 to 8, and 12 hours after treatment administration.
All dogs had significant decreases in pHa, PaO2, and oxygen saturation of hemoglobin, and significant increases in PaCO2 and alveolar-arterial oxygen differences in the postoperative period, but these changes were less severe in group-B dogs. Decreases of 50% in lung compliance, and increases of 100 to 200% in work of breathing and of 185 to 383% in pulmonary resistance were observed in all dogs after surgery. Increases in work of breathing were lower, and returned to preoperative values earlier in group-B dogs. The inspiratory time-to-total respiratory time ratio was significantly higher in group-B dogs during post-operative hours 5 to 8, suggesting improved analgesia. Blood pressure was significantly lower in group-A dogs for the first postoperative hour. Significant decreases in rectal temperature were observed in all dogs after surgery, and hypothermia was prolonged in dogs of groups A and C. Significant differences in pain score were not observed between treatment groups. Cortisol concentration was high in all dogs after anesthesia and surgery, and was significantly increased in group-B dogs at hours 4 and 8. Significant differences in serum morphine concentration between groups A and C were only observed 10 minutes after treatment administration. In general, significant differences in physiologic variables between groups A and C were not observed.
Results of the study indicate that anesthesia and thoracotomy are associated with significant alterations in pulmonary function and lung mechanics. Interpleurally administered bupivacaine appears to be associated with fewer blood gas alterations and earlier return to normal of certain pulmonary function values. Interpleural administration of morphine does not appear to provide any advantages, in terms of analgesia or pulmonary function, compared with its im administration.
Prothrombotic events in the prodromal stages of acute laminitis in horse
Authors: Weiss Douglas J. , Trent Ava M. , Johnston Gary 
Published: January 2024

SUMMARY
Prothrombotic changes occurring in the prodromal stages of carbohydrate-induced laminitis were investigated. Hemostatic alterations were evaluated by determining platelet counts, platelet survival, activated partial thromboplastin time, one-stage prothrombin time, and monocyte procoagulant activity. Thrombosis of vessels in the hoof wall was evaluated by contrast arteriography and histologic examination. Of 5 horses, 4 became lame between 28 and 52 hours after carbohydrate administration. Mean platelet count in laminitis-affected horses was lower throughout the prodromal stages of laminitis, compared with that in control horses, but differences were not statistically significant. However, survival of indium-111-labeled platelets was less than the value in control horses by 6 hours after carbohydrate administration. Arteriography of disarticulated feet revealed marked reduction in blood supply to hooves in laminitis-affected horses. Histologic examination of the laminar dermis disclosed microthrombi in venules of the laminar dermis in 2 of 4 affected horses. Statistically significant changes in prothrombin time were not observed, and changes in activated partial thromboplastin time were slight and occurred only at the onset of lameness. Statistically significant changes in monocyte procoagulant activity were not observed. Plasma endotoxin-like activity was not detected in laminitis-affected horses. These data indicate that platelet survival was decreased within the first 6 hours after induction of carbohydrate-induced laminitis, but systemic activation of the coagulation system was not detected.
Histologic evaluation of tissue reactivity and absorption in response to a new synthetic fluorescent pigmented polypropylene suture material in rats
Authors: Beardsley Stephanie L. , Smeak Daniel D. , Weisbrode Steven E. 
Published: January 2024

SUMMARY
The degree and type of tissue reactivity and the absorption of a new suture material was determined by implantation within rat gluteal muscles. Amount and type of tissue inflammatory reaction was compared among the new suture material, polypropylene, and coated polyamide.
Histologic evaluation of the tissues in which sutures were implanted indicated that the new suture material, polypropylene, and coated polyamide had similar amounts and types of reaction at 30 days or less after implantation, but differed after 30 days. The new suture material and polypropylene had an inflammatory reaction zone measuring less than 25% of the high-power field after 60 days, but the coated polyamide still induced reaction greater than 45% of the field at 90 days. At 60 and 90 days after implantation, the new suture material and polypropylene induced a mature fibrous reaction; the reaction to coated polyamide was either immature fibrous or granulomatous, depending on whether there was rupture of the suture coat. There was no observable absorption of the new suture material at 90 days.
This study indicated that the new suture material is nonabsorbable and is minimally reactive in rat muscle. The tissue reactions induced by this suture material are similar to those of polypropylene and significantly less than those induced by coated polyamide after 30 days following implantation.
Sonographic-anatomic correlation and imaging protocol for the kidneys of horses
Authors: Hoffmann K. L. , Wood A. K. W. , McCarthy P. H. 
Published: January 2024

SUMMARY
Sonographic and anatomic observations were made of the kidneys of 23 Thoroughbreds or Standardbreds. In an in vitro study of 16 horses, precise correlations were established between the gross anatomic features of the kidneys and their sonographic appearance in images obtained in dorsal, sagittal, transverse, and transverse oblique anatomic planes. The renal cortex had a uniformly mottled echogenicity, and the renal medulla was relatively hypoechogenic, compared with the cortex. Acoustic anisotropy was observed in the cortex and medulla of the cranial and caudal extremities of each kidney. The distinctive renal pelvis was seen in the transverse plane as an echogenic pair of diverging lines that lead to the crescent shaped renal crest in the lateral half of the kidney. In images made in the sagittal plane, the renal pelvis was seen as a pair of parallel echogenic lines separated by the moderately echogenic line of the renal crest. The terminal recesses were best seen in the transverse oblique views of each extremity, where they appeared as moderately echogenic lines in the medulla of the cranial and caudal extremities. The interlobar vessels were represented as irregular echogenic lines in the medulla, and the arcuate vessels were seen as echogenic points at the corticomedullary junction. At the hilus, the renal artery or its branches was located cranial to the renal vein, which in turn was cranial to the position of the proximal portion of the ureter.
In an in vivo study of 7 horses, sonographic images of the right kidney were obtained in the sagittal, transverse, and transverse oblique anatomic planes in all horses, with the transducer positioned at the 15th, 16th, or 17th intercostal space; images in the dorsal plane were obtained, however, in only 3 of the horses. For the left kidney, sonographic images were obtained in each of the anatomic planes when the transducer was positioned at the 16th or 17th intercostal space or the paralumbar fossa; rectal location of the transducer gave images in the dorsal and sagittal planes.
In this study, a routine sonographic imaging protocol, using standard anatomic planes, enabled each kidney to be examined in its entirety. The protocol provided definition of normal renal sonographic anatomic features and may permit a more informed and accurate recognition of renal pathologic change.