Supravalvular mitral stenosis in a cat

A 3-year-old, 4-kg, castrated male domestic shorthair cat presented with signs of progressive respiratory distress. Thoracic radiographs showed pulmonary edema and pleural effusion. Echocardiography revealed a perforate membrane immediately above the mitral valve that divided the left atrium into proximal and distal chambers. The left auricle was proximal to the dividing membrane and connected to the markedly enlarged proximal left atrial chamber, consistent with the diagnosis of supravalvular mitral stenosis (SMS). Position of the obstructing membrane relative to the left auricle distinguishes SMS from cor triatriatum sinister (CTS). In CTS, the left auricle is distal to the dividing membrane and connects to the distal left atrial chamber.     

Successful balloon angioplasty of pulmonary artery stenosis in two cats and associated complications

Two cats (2.5 months and 8 months old) were each evaluated due to a loud systolic murmur, and each was diagnosed with severe pulmonary artery stenosis at the bifurcation of the main pulmonary artery. Echocardiograms confirmed significant right atrial dilation and right ventricular dilation and/or hypertrophy that was progressive in one cat. Atenolol was initiated and the cats were referred for interventional therapy. Balloon angioplasty was performed via the jugular vein. In case 1, the pressure gradient across the stenosis was reduced from 169.7 mmHg to 23.6 mmHg and 52.4 mmHg across the left and right branch pulmonary arteries, respectively. In case 2, the stenotic echocardiographic gradient was reduced from 64 mmHg to 38.0 mmHg and 35.3 mmHg across the left branch and right-branched pulmonary arteries respectively. Both patients developed moderate to severe dynamic right ventricular outflow tract obstruction post angioplasty. Case 2 developed hypotension, desaturation, and ventricular arrhythmias intra-operatively. Case 1 was discharged but appeared to develop acute lung perfusion injury approximately 36 h after procedure that was manifested by radiographic pulmonary congestion and pulmonary infiltrate of the left lung fields. The congestion was successfully managed medically. Serial echocardiograms over the following 4 years in case 1 showed near complete resolution of the stenosis and associated right heart enlargement.     

Investigation of Two Magnetic Permanently Confined Micelle Array Sorbents Using Nonionic and Cationic Surfactants for the Removal of PAHs and Pesticides from Aqueous Media

Surfactants have been used for environmental remediation to remove hydrophobic organic compounds (HOCs) in water and soil. However, there are limited studies on the use of surfactants in confined micelle arrays to remove pesticides and polycyclic aromatic hydrocarbons from water. We studied the recovery of HOCs using two confined surfactants: nonionic Triton X-100 and cationic 3-(trimethoxysily)propyl-octadecyldimethyl-ammonium chloride (TPODAC). The micelle arrays were confined on a mesoporous silica matrix deposited onto a magnetic iron core. These magnetic, dispersible sorbents can be used to recover HOCs, minimizing the application of surfactants when compared to soil-washing techniques. The TPODAC-based sorbent had better average recovery of the HOCs studied compared to the Triton-X sorbent, and was, in general, comparable to activated carbon. It performed well with the chlorinated pesticides, in part due to additional interactions between the cationic sites and the polar compounds.     

Faecal shedding, alimentary clearance and intestinal spread of prions in hamsters fed with scrapie

Shedding of prions via faeces may be involved in the transmission of contagious prion diseases. Here, we fed hamsters 10mg of 263K scrapie brain homogenate and examined the faecal excretion of disease-associated prion protein (PrP(TSE)) during the course of infection. The intestinal fate of ingested PrP(TSE) was further investigated by monitoring the deposition of the protein in components of the gut wall using immunohistochemistry and paraffin-embedded tissue (PET) blotting. Western blotting of faecal extracts showed shedding of PrP(TSE) in the excrement at 24-72 h post infection (hpi), but not at 0-24 hpi or at later preclinical or clinical time points. About 5% of the ingested PrP(TSE) were excreted via the faeces. However, the bulk of PrP(TSE) was cleared from the alimentary canal, most probably by degradation, while an indiscernible proportion of the inoculum triggered intestinal infection. Components of the gut-associated lymphoid tissue (GALT) and the enteric nervous system (ENS) showed progressing accumulation of PrP(TSE) from 30 days post infection (dpi) and 60 dpi, respectively. At the clinical stage of disease, substantial deposits of PrP(TSE) were found in the GALT in close vicinity to the intestinal lumen. Despite an apparent possibility of shedding from Peyer's patches that may involve the follicle-associated epithelium (FAE), only small amounts of PrP(TSE) were detected in faeces from clinically infected animals by serial protein misfolding cyclic amplification (sPMCA). Although excrement may thus provide a vehicle for the release of endogenously formed PrP(TSE), intestinal clearance mechanisms seem to partially counteract such a mode of prion dissemination.     

Evaluation of the relationship between causative organisms and clinical characteristics of infective endocarditis in dogs: 71 cases (1992-2005)

OBJECTIVE: To evaluate microbiologic findings in dogs with infective endocarditis (IE) and determine whether there were differences in clinical features of disease caused by different groups of infective agents. DESIGN: Retrospective case series. ANIMALS: 71 dogs with suspected or definite IE. PROCEDURES: Medical records were reviewed for results of bacterial culture and susceptibility testing, serologic assays for vector-borne disease, and PCR testing on vegetative growths. Cases were grouped by causative organism and relationships among infectious agent group, and various hematologic, biochemical, and clinical variables were determined. Survival analyses were used to determine associations between infecting organisms and outcome. RESULTS: Causative bacteria were identified in 41 of 71 (58%) dogs. Gram-positive cocci were the causative agents in most (21/41; 51%) infections, with Streptococcus canis associated with 24% of infections. Gram-negative organisms were detected in 9 of the 41 (22%) dogs. Infection with Bartonella spp was detected in 6 of 31 (19%) dogs with negative results for microbial growth on blood culture. Aortic valve involvement and congestive heart failure were more frequent in dogs with endocarditis from Bartonella spp infection, and those dogs were more likely to be afebrile. Infection with Bartonella spp was negatively correlated with survival. Mitral valve involvement and polyarthritis were more frequent in dogs with streptococcal endocarditis. CONCLUSIONS AND CLINICAL RELEVANCE: Streptococci were the most common cause of IE and were more likely to infect the mitral valve and be associated with polyarthritis. Dogs with IE secondary to Bartonella spp infection were often afebrile, more likely to develop congestive heart failure, rarely had mitral valve involvement, and had shorter survival times.     

Spurious hypercreatininemia: 28 neonatal foals (2000–2008)

Objectives – To (1) determine the occurrence of spurious hypercreatininemia in a population of hospitalized foals <2 days old, (2) assess the resolution of the hypercreatininemia, and (3) determine its association with survival in these foals. Design – Retrospective case series. Setting – 2 Referral hospitals. Animals – Foals <2 days old with an admission creatinine >442 μmol/L (>5.0 mg/dL) from 2 referral hospitals. Interventions – None. Measurements and Main Results – The medical records of 33 foals were reviewed. Twenty‐eight had spurious hypercreatininemia and 5 had acute renal failure. Admission creatinine was not significantly different between the 2 groups (mean [standard deviation]). The creatinine was 1,202 μmol/L (663 μmol/L) (13.6 mg/dL [7.5 mg/dL]) versus 1,185 μmol/L (787 μmol/L) (13.4 mg/dL [8.9 mg/d]) (P=0.96) in each group, respectively, though BUN at the time of hospital admission was significantly higher for acute renal failure foals (P=0.009). In the spurious group, serum creatinine at admission decreased to 504 μmol/L (380 μmol/L) (5.7 mg/dL [4.3 mg/dL]) by 24 hours, and to 159 μmol/L (80 μmol/L) (1.8 mg/dL [0.9 mg/dL]) at 48 hours, and to 115 μmol/L (44 μmol/L) (1.3 mg/dL [0.5 mg/dL]) at 72 hours. Twenty‐three of 28 foals with spurious hypercreatininemia survived to hospital discharge and there was no difference in mean admission creatinine between survivors (1176 μmol/L [628 μmol/L]) (13.3 mg/dL [7.1 mg/dL]) and nonsurvivors (1308 μmol/L [857 μmol/L]) (14.8 mg/dL [9.7 mg/dL]) (P=0.67). Twenty of 28 foals had clinical signs suggestive of neonatal encephalopathy. Conclusion – Creatinine decreased by >50% within the initial 24 hours of standard neonatal therapy and was within the reference interval in all but 1 foal within 72 hours of hospitalization. The diagnosis of neonatal encephalopathy was common in these foals.     

Salmonella,Campylobacter, Clostridium difficile,and anti‐microbial resistant Escherichia coli in the faeces of sympatric meso‐mammals in southern Ontario,Canada

The role of free‐ranging wildlife in the epidemiology of enteropathogens causing clinical illness in humans and domestic animals is unclear. Salmonella enterica and anti‐microbial resistant bacteria have been detected in the faeces of raccoons (Procyon lotor), but little is known about the carriage of these bacteria in other sympatric meso‐mammals. Our objectives were to: (a) report the prevalence of Salmonella and associated anti‐microbial resistance, Campylobacter spp, Clostridium difficile, and anti‐microbial resistant Escherichia coli in the faeces of striped skunks (Mephitis mephitis) and Virginia opossums (Didelphis virginiana) in southern Ontario; and (b) compare the prevalence of these bacteria in the faeces of these meso‐mammal hosts with raccoons from a previously reported study. Faecal swabs were collected from striped skunks and Virginia opossums on five swine farms and five conservation areas from 2011 to 2013. Salmonella was detected in 41% (9/22) and 5% (5/95) of faecal swabs from Virginia opossums and striped skunks, respectively. None of the Salmonella serovars carried resistance to anti‐microbials. The prevalence of Campylobacter spp., C. difficile, and anti‐microbial resistant E. coli ranged from 6% to 22% in striped skunk and Virginia opossums. Using exact logistic regression, Salmonella was significantly more likely to be detected in faecal swabs of Virginia opossums than skunks and significantly less likely in faecal swabs from skunks than raccoons from a previously reported study. In addition, Campylobacter spp. was significantly more likely to be detected in raccoons than opossums. Salmonella Give was detected in 8/9 (89%) of Salmonella‐positive Virginia opossum faecal swabs. Our results suggest that striped skunks and Virginia opossums have the potential to carry pathogenic enteric bacteria in their faeces. The high prevalence of Salmonella Give in Virginia opossum faecal swabs in this study as well as its common occurrence in other Virginia opossum studies throughout North America suggests Virginia opossums may be reservoirs of this serovar.     

Breeding for yield in dry bean (Phaseolus vulgaris L.)

Strategies employed by dry bean breeders to improve yield include early generation testing, ideotype breeding, selection for physiological efficiency, and selection based on genotypic performance and combining ability across gene pools of Phaseolus vulgaris. Ideotype breeding has been successfully deployed to improve yield in navy, pinto and great northern seed types. The ideotype method is based on an ideal plant architecture to which breeders target their selection. Breeding for physiological efficiency is important in combining increased biomass, high growth rates and efficient partitioning. Genotypic performance and combining ability are also critical for yield improvement, since crosses between gene pools can exhibit negative combining ability and problems with lethality, whereas interracial crosses within the same gene pool exhibit the greatest potential. Breeders must work within specific constraints for growth habit, maturity, seed quality and disease resistance. A three-tiered pyramidal breeding strategy is proposed to facilitate yield improvement in dry bean. Breeding of elite, agronomically acceptable germplasm within the same market class is restricted to the apex of the pyramid. The intermediate level has fewer constraints and greater access to diverse germplasm. Interracial crosses within the same gene pool are utilized to exploit genetic differences within adapted material. Extracting genetic diversity from unadapted sources, including wild germplasm and other Phaseolus species, is conducted at the base of the pyramid. The objective of this breeding strategy is the movement of improved germplasm towards the apex, using different breeding procedures to optimize improvement at each tier of the breeding pyramid. This revised version was published online in July 2006 with corrections to the Cover Date.