Refinar búsqueda
Resultados 351-360 de 535
Effect of histologic processing on dimensions of skin samples obtained from cat cadavers Texto completo
2015
Jeyakumar, Sakthila | Smith, Annette N. | Schleis, Stephanie E. | Cattley, Russell C. | Tillson, Michael | Henderson, Ralph A.
OBJECTIVE To determine changes in dimensions of feline skin samples as a result of histologic processing and to identify factors that contributed to changes in dimensions of skin samples after sample collection. SAMPLE Cadavers of 12 clinically normal cats. PROCEDURES Skin samples were obtained bilaterally from 3 locations (neck, thorax, and tibia) of each cadaver; half of the thoracic samples included underlying muscle. Length, width, and depth were measured at 5 time points (before excision, after excision, after application of ink to mark tissue margins, after fixation in neutral-buffered 10% formalin for 36 hours, and after completion of histologic processing and staining with H&E stain). Measurements obtained after sample collection were compared with measurements obtained before excision. RESULTS At the final time point, tissue samples had decreased in length (mean decrease, 32.40%) and width (mean decrease, 34.21%) and increased in depth (mean increase, 54.95%). Tissue from the tibia had the most shrinkage in length and width and that from the neck had the least shrinkage. Inclusion of underlying muscle on thoracic skin samples did not affect the degree of change in dimensions. CONCLUSIONS AND CLINICAL RELEVANCE In this study, each step during processing from excision to formalin fixation and histologic processing induced changes in tissue dimensions, which were manifested principally as shrinkage in length and width and increase in depth. Most of the changes occured during histologic processing. Inclusion of muscle did not affect thoracic skin shrinkage. Shrinkage should be a consideration when interpreting surgical margins in clinical cases.
Mostrar más [+] Menos [-]Analytic validation of a gas chromatography–mass spectrometry method for quantification of six amino acids in canine serum samples Texto completo
2015
Lopes, Rosana | Grutzner, Niels | Berghoff, Nora | Lidbury, Jonathan A. | Suchodolski, Jan S. | Steiner, Jörg M.
OBJECTIVE To analytically validate a gas concentration of chromatography–mass spectrometry (GC-MS) method for measurement of 6 amino acids in canine serum samples and to assess the stability of each amino acid after sample storage. SAMPLES Surplus serum from 80 canine samples submitted to the Gastrointestinal Laboratory at Texas A&M University and serum samples from 12 healthy dogs. PROCEDURES GC-MS was validated to determine precision, reproducibility, limit of detection, and percentage recovery of known added concentrations of 6 amino acids in surplus serum samples. Amino acid concentrations in serum samples from healthy dogs were measured before (baseline) and after storage in various conditions. RESULTS Intra- and interassay coefficients of variation (10 replicates involving 12 pooled serum samples) were 13.4% and 16.6% for glycine, 9.3% and 12.4% for glutamic acid, 5.1% and 6.3% for methionine, 14.0% and 15.1% for tryptophan, 6.2% and 11.0% for tyrosine, and 7.4% and 12.4% for lysine, respectively. Observed-to-expected concentration ratios in dilutional parallelism tests (6 replicates involving 6 pooled serum samples) were 79.5% to 111.5% for glycine, 80.9% to 123.0% for glutamic acid, 77.8% to 111.0% for methionine, 85.2% to 98.0% for tryptophan, 79.4% to 115.0% for tyrosine, and 79.4% to 110.0% for lysine. No amino acid concentration changed significantly from baseline after serum sample storage at −80°C for ≤ 7 days. CONCLUSIONS AND CLINICAL RELEVANCE GC-MS measurement of concentration of 6 amino acids in canine serum samples yielded precise, accurate, and reproducible results. Sample storage at −80°C for 1 week had no effect on GC-MS results.
Mostrar más [+] Menos [-]Effect of castration on the urinary protein-to-creatinine ratio of male dogs Texto completo
2015
Bertieri, Marie-Blanche | Lapointe, Catherine | Conversy, Berenice | Gara-Boivin, Carolyn
OBJECTIVE To assess the urinary protein-to-creatinine ratio (UPCR) of healthy sexually intact male dogs and to compare the UPCR of these dogs before and after castration. ANIMALS 19 client- or shelter-owned healthy adult sexually intact male dogs. PROCEDURES Physical, hematologic, and biochemical examinations and urinalysis (including calculation of the UPCR) were performed on each dog. Dogs were then castrated, and physical examination and urinalysis (including calculation of the UPCR) were performed again at least 15 days after castration. RESULTS A dipstick test yielded positive results for protein in the urine of 10 sexually intact male dogs, but the UPCR was < 0.5 for all sexually intact male dogs. Mean UPCR for sexually intact male dogs was 0.12 (range, 0.10 to 0.32). The UPCR was < 0.2 for all castrated dogs, except for 1. Mean UPCR for all castrated dogs was 0.08 (range, 0.05 to 0.69). There was a significant difference between mean UPCR before and after castration. CONCLUSIONS AND CLINICAL RELEVANCE In this study, pathological proteinuria was not detected in sexually intact male dogs. Positive results for a urine dipstick test should be interpreted with caution in sexually intact male dogs and should be confirmed by assessment of the UPCR. An increased UPCR in sexually intact male dogs may be considered abnormal.
Mostrar más [+] Menos [-]Induction of thioredoxin-1 in response to oxidative stress in dogs Texto completo
2015
Munakata, Shuntaro | Tanaka, Yoshikazu | Nezu, Yoshinori | Harada, Yasuji | Yogo, Takuya | Hara, Yasushi | Tian, Hai | Matsuo, Yoshiyuki | Tagawa, Masahiro | Yodoi, Junji
OBJECTIVE To determine whether thioredoxin (TRX)-1 can be used as a valid biomarker for oxidative stress in dogs. ANIMALS AND SAMPLES 10 Beagles and Madin-Darby canine kidney cells. PROCEDURES Madin-Darby canine kidney cells were used to verify antigen cross-reactivity between human and canine anti–TRX-antibodies. Dogs were assigned to receive 21% or 100% O2 (5 dogs/group) via an artificial respirator during a 3-hour period of isoflurane anesthesia (starting at 0 hours). Blood and urine samples were collected before (baseline) and at 6, 12, 24, and 48 hours after commencement of inhalation anesthesia. Concentrations of TRX-1 and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in plasma and urine samples were analyzed; urine concentrations were reported as ratios against urine creatinine concentration. RESULTS Canine TRX-1 was recognized by monoclonal human anti-TRX-1 antibodies (clones of adult T-cell leukemia-derived factor [ADF]-11 and ADF21) by western blot analysis. Results of an ELISA indicated that plasma TRX-1 concentration and urine TRX-1-to-creatinine concentration ratio increased rapidly after the 3-hour period of hyperoxia with maximal peaks at 12 and 6 hours, respectively. Urine 8-OHdG-to-creatinine concentration ratio also increased significantly after hyperoxia induction. However, unlike the rapid increase in urine TRX-1-to-creatinine concentration ratio, maximal urine 8-OHdG-to-creatinine concentration ratio was attained at 48 hours after hyperoxia induction. These variables remained unchanged from baseline in the control group. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that human anti-TRX monoclonal antibodies cross-reacted with canine TRX, and plasma TRX-1 concentrations were rapidly increased in dogs following an oxidative stress challenge. Thus, TRX may be a valuable clinical biomarker for detecting oxidative stress more rapidly than 8-OHdG in dogs.
Mostrar más [+] Menos [-]Blocking the expression of syntaxin 4 interferes with initial phagocytosis of Brucella melitensis in macrophages Texto completo
2015
Castaneda-Ramirez, Alfredo | Gonzalez-Rodriguez, Diana | Hernandez-Pineda, J Aide | Verdugo-Rodriguez, Antonio
Brucella melitensis is the Brucella species most frequently associated with brucellosis in humans. It is also the causative agent of the disease in goats and other ruminants. Although significant aspects of the pathogenesis of infection by this intracellular pathogen have been clarified, several events during invasion of host cells remain to be elucidated. In this study, infections of human macrophages from the THP-1 monocyte cell line were conducted with B. melitensis Bm133 wild-type strain and a strain of Salmonella serovar Enteritidis as a control. A multiplicity of infection of 100 was used in trials focused on defining the relative expression of syntaxin 4 (STX4), a soluble N-ethylmaleimide-sensitive factor attachment protein receptor, in the early events of phagocytosis (at 15, 30, 45, and 60 min). Immunoblot assays were also done to visualize expression of the protein in cells infected with either bacterial strain. The expression of STX4 was not significantly different in cells infected with B. melitensis strain Bm133 compared to that observed in cells infected with S. Enteritidis. When the expression of STX4 mRNA was inhibited with short or small interfering, or silencing, RNA in the THP-1 cells, the survival of B. melitensis was significantly reduced at time 0, when gentamicin treatment of cultures was begun (after 1 h of phagocytosis), and also at 2 h and 12 h after infection.
Mostrar más [+] Menos [-]Comparison of limb loading and movement of Icelandic horses while tölting and trotting at equal speeds Texto completo
2015
Waldern, Nina M. | Wiestner, Thomas | Ramseier, Lea C. | Weishaupt, Michael A.
OBJECTIVE To compare gait mechanics and limb loading in Icelandic horses tölting and trotting at equal speeds and estimate their impact on orthopedic health. ANIMALS 12 orthopedically normal Icelandic horses. PROCEDURES Kinetic and kinematic gait variables were simultaneously recorded as each horse was ridden at a tölt and trot on an instrumented treadmill at 3.4 m/s and 3.9 m/s. Differences between gaits were tested via 1-factor repeated-measures ANOVA. RESULTS Horses had a higher stride rate and lower stride impulses at a tölt than at a trot. For forelimbs at a tölt, shorter relative stance duration resulted in higher peak vertical force (Fz(peak)). Conversely, for hind limbs, longer relative stance duration resulted in lower Fz(peak). The higher head-neck position at a tölt versus trot caused no weight shift to the hind limbs, but a higher forehoof flight arc and lower proretraction movement were identified. Stance durations for forelimbs were briefer than for hind limbs at a tölt, and the inverse was observed at a trot. Minimal height of the horse's trunk at the point of Fz(peak) of the respective limb suggested a spring-like mechanism for all limbs at a tölt. Hind limb measurements revealed no evidence of increased collection. Stride-to-stride limb timing varied more at a tölt than at a trot. At a trot, horses had brief or no suspension phases and a slightly 4-beated footfall rhythm was common. Post hoc energetic estimations revealed that tölting at the measured speeds was less advantageous than trotting. CONCLUSIONS AND CLINICAL RELEVANCE High forelimb action in Icelandic horses and higher head-neck position at a tölt were associated with more restricted limb proretraction, higher Fzpeak, and faster force onset than at a trot. The impact of these differences on orthopedic health needs to be investigated more in detail.
Mostrar más [+] Menos [-]Effects of high doses of enalapril and benazepril on the pharmacologically activated renin-angiotensin-aldosterone system in clinically normal dogs Texto completo
2015
Ames, Marisa K. | Atkins, Clarke E. | Lee, Seunggon | Lantis, Andrea C. | zumBrunnen, James R.
OBJECTIVE To determine whether high doses of enalapril and benazepril would be more effective than standard doses of these drugs in suppressing the furosemide-activated renin-angiotensin-aldosterone system (RAAS). ANIMALS 6 healthy Beagles. PROCEDURES 2 experiments were conducted; each lasted 10 days, separated by a 2-week washout period. In experiment 1, all dogs received furosemide (2 mg/kg, PO, q 12 h) and enalapril (1 mg/kg, PO, q 12 h) for 8 days (days 0 through 7). In experiment 2, dogs received furosemide (2 mg/kg, PO, q 12 h) and benazepril (1 mg/kg, PO, q 12 h) for 8 days. Effects on the RAAS were determined by assessing serum angiotensin-converting enzyme (ACE) activity on days −1, 3, and 7; serum aldosterone concentration on days −2, −1, 1, 3, and 7; and the urinary aldosterone-creatinine ratio (UAldo:C) in urine collected in the morning and evening of days −2, −1, 1, 3, and 7. RESULTS High doses of enalapril and benazepril caused significant reductions in serum ACE activity on all days but were not more effective than standard doses used in other studies. Mean UAldo:C remained significantly higher on days 2 through 7, compared with baseline values. Serum aldosterone concentration also increased after drug administration, which mirrored changes in the UAldo:C. CONCLUSIONS AND CLINICAL RELEVANCE In this study, administration of high doses of enalapril and benazepril significantly inhibited ACE activity, yet did not prevent increases in mean urine and serum aldosterone concentrations resulting from furosemide activation of RAAS. This suggested that aldosterone breakthrough from ACE inhibition was a dose-independent effect of ACE inhibitors.
Mostrar más [+] Menos [-]Dynamic computed tomographic determination of scan delay for use in performing cardiac angiography in clinically normal dogs Texto completo
2015
Kim, Jisun | Bae, Yeonho | Lee, Gahyun | Jeon, Sunghoon | Choi, Jihye
OBJECTIVE To determine the scan delay for use in performing cardiac CT angiography in dogs. ANIMALS 4 clinically normal adult Beagles. PROCEDURES In a crossover study, 12 formulations of iohexol solutions differing in iodine dose (300, 400, and 800 mg/kg) and concentration (undiluted and diluted 1:1, 1:2, and 1:3 with saline [0.9% NaCl] solution) were administered IV to each dog. Dynamic CT angiography was performed to evaluate enhancement characteristics of each formulation, with the region of interest set over the aorta. Time-attenuation curves (TACs) were obtained and analyzed. RESULTS Peak arc–type TACs were obtained after administration of all undiluted formulations. Curve shape changed from peak arc type to plateau type as the total volume of the contrast solution (ie, dilution) increased. Prolonged peaks characteristic of plateau-type TACs suggested that a sufficient period of homogeneous attenuation could be achieved for CT scanning with administration of higher iohexol dilutions (1:2 or 1:3) containing higher iodine doses (400 or 800 mg/kg). In particular, attenuation values for plateau-type TACs remained between 200 and 300 Hounsfield units for > 16 seconds after the plateau endpoint was reached for 1:2 and 1:3 dilutions containing an iodine dose of 800 mg/kg. Scan delays of 13 to 17 seconds were computed for those 2 formulations. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that for clinically normal dogs, a scan delay of 13 to 17 seconds could be used to perform cardiac CT angiography with iohexol solutions containing an iodine dose of 800 mg/kg at dilutions of 1:2 or 1:3.
Mostrar más [+] Menos [-]Mixed viral infections in village chickens Texto completo
2015
Leow, B. L. | Norazura B. | Mohd Jihan R. | Mohd Khairil A. | Basirah M. A. | Ong, G. H. | Faizul Fikri M. Y. | Ramlan M. | Maizatul Z. | Muhammad Redzwan S.
A mixed viral infection of Newcastle Disease (ND), Marek’s Disease (MD) and Avian Leukosis (AL) was reported in village chickens. Analysis of the deduced amino acid sequences of the F protein cleavage site of ND virus showed that the isolate was virulent with sequence KRRKR for the C-terminus of the F2 protein and phenylanine (F) at residue 117, the N-terminus of the F1 protein. Basic Local Alignment Search Tool (BLAST) analysis showed the isolate was ND which was 96% similar identity with Indonesia Sukorejo genotype VII, MD 99% similar identity with China very virulent strain and ALV 100% similar identity with Taiwan ALV strain. Due to the free ranging type of management, causes of the diseases in the poultry were uncertain as many factors can contribute to the disease occurrence. However, good hygiene practices can help to improve the farm’s sanitary. Basic biosecurity system can be applied although the success may be limited. Vaccination is another alternative that can be considered to prevent the diseases with the help from certain parties.
Mostrar más [+] Menos [-]Farmers and traders willingness to use and pay for animal identification and traceability system in Malaysia Texto completo
2015
M.A. Stevenson | L. Hassan | K. Ghazali | A.B. Salina | A.A. Saharee
Traceability system for livestock is an important infrastructurenecessary to monitor animal health, animal disease emergencies and quality assurance. The aim of this study was to evaluate farmer and trader willingness to use and pay for an animal identification and traceability system in Peninsular Malaysia. Data was obtained from aquestionnaire that was completed by 543 farmers and traders from the 10 states in the peninsula. Our results show that up to 54% respondents were willing to use and pay for an animal identification and traceability system. Gender and the length of experience of farmers and traders were factors significantly associated with theoutcome of this study. Female farmers and traders were less willing to use and pay for an animal identification and traceability system while farmers and traders with more experience in the cattle industrywere significantly more likely to provide a favourable response.
Mostrar más [+] Menos [-]