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Genome-wide sequencing and quantification of circulating microRNAs for dogs with congestive heart failure secondary to myxomatous mitral valve degeneration
2018
Jung, SeungWoo | Bohan, Amy
OBJECTIVE To characterize expression profiles of circulating microRNAs via genome-wide sequencing for dogs with congestive heart failure (CHF) secondary to myxomatous mitral valve degeneration (MMVD). ANIMALS 9 healthy client-owned dogs and 8 age-matched client-owned dogs with CHF secondary to MMVD. PROCEDURES Blood samples were collected before administering cardiac medications for the management of CHF. Isolated microRNAs from plasma were classified into microRNA libraries and subjected to next-generation sequencing (NGS) for genome-wide sequencing analysis and quantification of circulating microRNAs. Quantitative reverse transcription PCR (qRT-PCR) assays were used to validate expression profiles of differentially expressed circulating microRNAs identified from NGS analysis of dogs with CHF. RESULTS 326 microRNAs were identified with NGS analysis. Hierarchical analysis revealed distinct expression patterns of circulating microRNAs between healthy dogs and dogs with CHF. Results of qRT-PCR assays confirmed upregulation of 4 microRNAs (miR-133, miR-1, miR-let-7e, and miR-125) and downregulation of 4 selected microRNAs (miR-30c, miR-128, miR-142, and miR-423). Results of qRT-PCR assays were highly correlated with NGS data and supported the specificity of circulating microRNA expression profiles in dogs with CHF secondary to MMVD. CONCLUSIONS AND CLINICAL RELEVANCE These results suggested that circulating microRNA expression patterns were unique and could serve as molecular biomarkers of CHF in dogs with MMVD.
Afficher plus [+] Moins [-]Evaluation of ADAMTS17 in Chinese Shar-Pei with primary open-angle glaucoma, primary lens luxation, or both
2018
Oliver, James A. C. | Rustidge, Sophie | Pettitt, Louise | Jenkins, Christopher A. | Farias, Fabiana H. G. | Giuliano, Elizabeth A. | Mellersh, Cathryn S.
OBJECTIVE To evaluate the coding regions of ADAMTS17 for potential mutations in Chinese Shar-Pei with a diagnosis of primary open-angle glaucoma (POAG), primary lens luxation (PLL), or both. ANIMALS 63 Shar-Pei and 96 dogs of other breeds. PROCEDURES ADAMTS17 exon resequencing was performed on buccal mucosal DNA from 10 Shar-Pei with a diagnosis of POAG, PLL, or both (affected dogs). A candidate causal variant sequence was identified, and additional dogs (53 Shar-Pei [11 affected and 42 unaffected] and 95 dogs of other breeds) were genotyped for the variant sequence by amplified fragment length polymorphism analysis. Total RNA was extracted from ocular tissues of 1 affected Shar-Pei and 1 ophthalmologically normal Golden Retriever; ADAMTS17 cDNA was reverse transcribed and sequenced, and ADAMTS17 expression was evaluated by quantitative reverse-transcription PCR assay. RESULTS All affected Shar-Pei were homozygous for a 6-bp deletion in exon 22 of ADAMTS17 predicted to affect the resultant protein. All unaffected Shar-Pei were heterozygous or homozygous for the wild-type allele. The variant sequence was significantly associated with affected status (diagnosis of POAG, PLL, or both). All dogs of other breeds were homozygous for the wild-type allele. The cDNA sequencing confirmed presence of the expected variant mRNA sequence in ocular tissue from the affected dog only. Gene expression analysis revealed a 4.24-fold decrease in the expression of ADAMTS17 in ocular tissue from the affected dog. CONCLUSIONS AND CLINICAL RELEVANCE Results supported that the phenotype (diagnosis of POAG, PLL, or both) is an autosomal recessive trait in Shar-Pei significantly associated with the identified mutation in ADAMTS17.
Afficher plus [+] Moins [-]Determination of anatomic landmarks for optimal placement in captive-bolt euthanasia of goats
2018
Plummer, Paul J. | Shearer, Jan K. | Kleinhenz, Katie E. | Shearer, Leslie C.
OBJECTIVE To determine the optimal anatomic site and directional aim of a penetrating captive bolt (PCB) for euthanasia of goats. SAMPLE 8 skulls from horned and polled goat cadavers and 10 anesthetized horned and polled goats scheduled to be euthanized at the end of a teaching laboratory. PROCEDURES Sagittal sections of cadaver skulls from 8 horned and polled goats were used to determine the ideal anatomic site and aiming of a PCB to maximize damage to the midbrain region of the brainstem for euthanasia. Anatomic sites for ideal placement and directional aiming were confirmed by use of 10 anesthetized horned and polled goats. RESULTS Clinical observation and postmortem examination of the sagittal sections of skulls from the 10 anesthetized goats that were euthanized confirmed that perpendicular placement and firing of a PCB at the intersection of 2 lines, each drawn from the lateral canthus of 1 eye to the middle of the base of the opposite ear, resulted in consistent disruption of the midbrain and thalamus in all goats. Immediate cessation of breathing, followed by a loss of heartbeat in all 10 of the anesthetized goats, confirmed that use of this site consistently resulted in effective euthanasia. CONCLUSIONS AND CLINICAL RELEVANCE Damage to the brainstem and key adjacent structures may be accomplished by firing a PCB perpendicular to the skull over the anatomic site identified at the intersection of 2 lines, each drawn from the lateral canthus of 1 eye to the middle of the base of the opposite ear.
Afficher plus [+] Moins [-]Comparison of antimicrobial resistance genes in feedlots and urban wastewater
2018
Beukers, A. G. | Zaheer, R. | Cook, S. R. | Chaves, A. V. | Ward, M. P. | Tymensen, L. | Morley, P. S. | Hannon, S. | Booker, C. W. | Read, R. R. | McAllister, T. A.
The use of antibiotics in livestock production in North America and possible association with elevated abundance of detectable antimicrobial resistance genes (ARG) is a growing concern. Real-time, quantitative PCR (RT-qPCR) was used to determine the relative abundance and diversity of ARG in fecal composite and catch basin samples from 4 beef feedlots in Alberta. Samples from a surrounding waterway and municipal wastewater treatment plants were also included to compare the ARG profile of urban environments and fresh water with that of feedlots. The relative abundance of 18 resistance genes across 5 antibiotic families including sulfonamides, tetracyclines, macrolides, fluoroquinolones, and β-lactams was examined. Sulfonamide, fluoroquinolone, and β-lactam resistance genes predominated in wastewater treatment samples, while tetracycline resistance genes predominated in cattle fecal composite samples. These results reflect the types of antibiotic that are used in cattle versus humans, but other factors such as co-selection of ARG and variation in the composition of bacterial communities associated with these samples may also play a role.
Afficher plus [+] Moins [-]Biological characteristics and conjugated antigens of ClfA A-FnBPA and CP5 in Staphylococcus aureus
2018
Li, Tao | Huang, M. | Song, Z. | Zhang, H. | Chen, C.
To obtain immunogenic conjugate antigens, adipic acid dihydrazide (ADH), as a bridge, and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimidehydrochloride (EDAC), as a coupling agent, were used to conjugate the purified fusion protein, clumping factor A-fibronectin binding protein ClfA A-FnBPA, and type 5 capsular polysaccharide (CP5). The conjugates were mixed with an adjuvant, and mice were immunized 3 times and challenged with Staphylococcus aureus 1 week later. Antibody titers were determined by indirect enzyme-linked immunosorbent assay (ELISA). At 14 days after the first immunization, antibodies against the purified protein and conjugate were detected; after 28 days, antibody levels increased; and a week after the third immunization, antibody levels continued to increase. However, the conjugate antibody titers were higher than those of the purified protein during the study, and no IgG antibodies against purified CP5 were detected during the entire experiment. The protection rate increased to 90% in the conjugate group, indicating that the conjugate imparts a relatively higher protective efficacy than the purified protein and purified CP5.
Afficher plus [+] Moins [-]Thromboelastographic evaluation of dogs bitten by rattlesnakes native to southern California
2018
Lieblick, Beth A. | Bergman, Philip J. | Peterson, Nathan W.
OBJECTIVE To validate that dogs become hypocoagulable following rattlesnake envenomation and to determine whether thromboelastographic abnormalities are correlated with envenomation severity for dogs bitten by rattlesnakes native to southern California. ANIMALS 14 dogs with observed or suspected rattlesnake envenomation (envenomated dogs) and 10 healthy control dogs. PROCEDURES For each dog, a citrate-anticoagulated blood sample underwent kaolin-activated thromboelastography. For each envenomated dog, a snakebite severity score was assigned on the basis of clinical findings, and prothrombin time, activated partial thromboplastin time, and platelet count were determined when the attending clinician deemed it necessary and owner finances allowed. RESULTS For 12 of 14 envenomated dogs, the thromboelastographically determined clot strength was below the 25th percentile for the clot strength of control dogs, which was indicative of a hypocoagulable state. No envenomated dog had thromboelastographic results indicative of a hypercoagulable state. One envenomated dog had a prolonged prothrombin time, but the activated partial thromboplastin time and all thromboelastographic variables were within the respective reference ranges for that dog. Seven of 13 envenomated dogs were thrombocytopenic (platelet count, ≤ 170,000 platelets/μL). Snakebite severity score was negatively correlated with platelet count but was not correlated with any thromboelastographic variable. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that dogs generally become hypocoagulable following rattlesnake envenomation. Thromboelastography might provide an objective measure of the coagulation status of envenomated dogs and aid in the identification of dogs that are in a hypocoagulable state and in need of antivenin treatment prior to the onset of progressive clinical signs.
Afficher plus [+] Moins [-]Effect of body position and time on quantitative computed tomographic measurements of lung volume and attenuation in healthy anesthetized cats
2018
Foo, Timothy S. | Pilton, Joanna L. | Hall, Evelyn J. | Martinez-Taboada, Ferando | Makara, Mariano
OBJECTIVE To quantify the effect of time and recumbency on CT measurements of lung volume and attenuation in healthy cats under general anesthesia. ANIMALS 8 healthy research cats. PROCEDURES Anesthetized cats were positioned in sternal recumbency for 20 minutes and then in left, right, and left lateral recumbency (40 minutes/position). Expiratory helical CT scan of the thorax was performed at 0 and 20 minutes in sternal recumbency and at 0, 5, 10, 20, 30, and 40 minutes in each lateral recumbent position. For each lung, CT measurements of lung volume and attenuation and the extent of lung areas that were hyperaerated (−1,000 to −901 Hounsfield units [HU]), normoaerated (−900 to −501 HU), poorly aerated (−500 to −101 HU), or nonaerated (−100 to +100 HU [indicative of atelectasis]) were determined with a semiautomatic threshold-based technique. A restricted maximum likelihood analysis was performed. RESULTS In lateral recumbency, the dependent lung had significantly greater attenuation and a lower volume than the nondependent lung. Within the dependent lung, there was a significantly higher percentage of poorly aerated lung tissue, compared with that in the nondependent lung. These changes were detected immediately after positioning the cats in lateral recumbency and remained static with no further significant time-related change. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that once anesthetized healthy cats were positioned in lateral recumbency, the dependent lung lobes underwent a rapid reduction in lung volume and increase in lung attenuation that did not progress over time, predominantly attributable to an increase in poorly aerated lung tissue.
Afficher plus [+] Moins [-]Retention of gadolinium in the brains of healthy dogs after a single intravenous administration of gadodiamide
2018
Gambino, Jennifer M. | James, Judy R. | Buchweitz, John P. | Cooley, A Jim | Lawrence, Amanda M. | Wills, Robert W. | Lee, Alison M.
OBJECTIVE To determine brain region affinity for and retention of gadolinium in dogs after administration of gadodiamide and whether formalin fixation affects quantification. ANIMALS 14 healthy dogs. PROCEDURES 13 dogs received gadodiamide (range, 0.006 to 0.1 mmol/kg, IV); 1 control dog received a placebo. Dogs received gadodiamide 3 to 7 days (n = 8) or 9 hours (5) before euthanasia and sample collection. Brain regions were analyzed with inductively coupled mass spectrometry (ICP-MS) and transmission electron microscopy. Associations between dose, time to euthanasia, and gadolinium retention quantities (before and after fixation in 5 dogs) were evaluated. RESULTS Gadolinium retention was seen in all brain regions at all doses, except for the control dog. Exposure 3 to 7 days before euthanasia resulted in 1.7 to 162.5 ng of gadolinium/g of brain tissue (dose-dependent effect), with cerebellum, parietal lobe, and brainstem affinity. Exposure 9 hours before euthanasia resulted in 67.3 to 1,216.4 ng of gadolinium/g of brain tissue without dose dependency. Transmission electron microscopy revealed gadolinium in examined tissues. Fixation did not affect quantification in samples immersed for up to 69 days. CONCLUSIONS AND CLINICAL RELEVANCE Gadodiamide exposure resulted in gadolinium retention in the brain of healthy dogs. Cerebellum, parietal lobe, and brainstem affinity was detected with dose dependency only in dogs exposed 3 to 7 days before euthanasia. Fixation had no effect on quantification when tissues were immersed for up to 69 days. Physiologic mechanisms for gadolinium retention remained unclear. The importance of gadolinium retention requires further investigation.
Afficher plus [+] Moins [-]Occurrence of the specific long spike burst pattern in the ovine proximal gallbladder as an indication of myoelectric regional variability
2018
Romański, Krzysztof W.(Wrocaw University of Environmental and Life Sciences Centre for Experimental Diagnostics and Biomedical Innovations) | Nicpoń, Józef(Wrocaw University of Environmental and Life Sciences Centre for Experimental Diagnostics and Biomedical Innovations)
The myoelectrical activity of the ovine gallbladder has not been fully recognised. Five rams were fitted with six small intestinal and three gallbladder electrodes and a strain gauge force transducer was mounted near the gallbladder fundic electrode. In two series of successive experiments, the electromyographical and mechanical recordings were recorded over a period of 5-7 hours. The occurrence of the slow waves in the small bowel was regular, unlike those in the gallbladder. In the gallbladder infundibulum, the specific pattern, called the long spike burst pattern (LSBP), was observed. It comprised usually one or two parts of prolonged duration. The first part resembled the classical (short lasting) spike burst in the small bowel, and its amplitude was lower than that of the second part. The spike burst frequency of the second part was 2-3 times lower than that of the first part. During phase 1-like and phase 2a-like activities, the intensity of the gallbladder LSBP was reduced while enhanced after feeding. In fasted rams, the duration of a specific pattern, observed in the gallbladder infundibulum, was longer than in non-fasted animals and its amplitude was low. Similar events were recorded in the gallbladder corpus, but the specific pattern was shorter and irregular. In the gallbladder fundus, mostly irregular short spike bursts were recorded. It is concluded that in sheep, specific types of the long-lasting groups of spikes occur in the upper gallbladder areas exhibiting myoelectrical regional variability. The character of an LSBP depends on feeding conditions.
Afficher plus [+] Moins [-]Spatial and temporal distribution of foot-and-mouth disease in four districts situated along the Uganda-Tanzania border: Implications for cross-border efforts in disease control
2018
Kerfua, Susan D.(Nelson Mandela African Institute of Science and Technology ,National Livestock Resources Research Institute) | Shirima, Gabriel(Nelson Mandela African Institute of Science and Technology) | Kusiluka, Lughano(Mzumbe University Department of Global Health and Biomedical Sciences) | Ayebazibwe, Chrisostome(National Animal Disease Diagnostics and Epidemiology Centre) | Mwebe, Robert(National Animal Disease Diagnostics and Epidemiology Centre) | Cleaveland, Sarah(University of Glasgow Institute of Biodiversity, Animal Health and Comparative Medicine) | Haydon, Daniel(University of Glasgow Institute of Biodiversity, Animal Health and Comparative Medicine)
Foot-and-mouth disease (FMD) is one of the major trans-boundary animal diseases in East Africa causing economic loss to farmers and other stakeholders in the livestock industry. Foot-and-mouth disease occurs widely in both Uganda and Tanzania with annual outbreaks recorded. With the recent introduction of the Progressive Control Pathway for FMD control (PCP-FMD) in eastern Africa, knowledge of the spatial and temporal distribution of FMD at the border area between Uganda and Tanzania is helpful in framing engagement with the initial stages of the PCP. Retrospective data collected between 2011 and 2016 from four districts located along the border areas of Uganda and Tanzania, recorded 23 and 59 FMD outbreaks, respectively, for the entire study period. Analysis showed that 46% of the 82 recorded outbreaks occurred in 20% of sub-counties and wards immediately neighbouring the Uganda-Tanzania border and 69.5% of the outbreaks occurred during the dry months. While the serotypes of the FMD virus responsible for most outbreaks reported in this region were not known, previous research reported South African Territory (SAT) 1, SAT 2 and O to be the serotypes in circulation. The results from this study provide evidence of the endemic status of FMD on the Uganda-Tanzania border and emphasise that the border area should be given due consideration during FMD control drives and that cross-border coordination should be prioritised. With the limited data on circulating serotypes in this area, there is a need for more vigilance on FMD case detection, laboratory diagnostic confirmation and provision of more complete documentation of outbreaks. This work further recommends more studies on cross-border livestock movement coupled with phylogenetics in order to understand the spread of the FMD in the border area.
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