Background: Class II major histocompatibility complex (MHC) is an independent predictor of outcome in human B‐cell lymphoma. We assessed class II expression together with other markers for their ...impact on prognosis in canine B‐cell lymphoma.
Hypothesis: Low class II MHC expression, large cell size, and expression of CD34 will predict a poorer outcome in canine B‐cell lymphoma. Expression of CD5 and CD21 on tumor cells also may be associated with outcome.
Animals: One hundred and sixty dogs with cytologically confirmed lymphoma.
Methods: Patient signalment, treatment type, and flow cytometry characteristics were analyzed for their influence on outcome. A multivariable predictive model of survival was generated using 2/3 of the patients and validated on the remaining 1/3 of the dataset.
Results: Class II MHC expression had a negative association with mortality and relapse. Treatment type also influenced relapse and mortality, whereas cell size and patient age was only associated with mortality. CD34, CD21, and CD5 expression was not associated with disease outcome. The constructed model performed variably in predicting the validation group's outcome at the 6‐month time point.
Conclusions and Clinical Importance: Low levels of class II MHC expression on B‐cell lymphoma predict a poor outcome, as in human B‐cell lymphoma. This finding has implications for the use of dogs to model human lymphomas. Class II expression, cell size, treatment, and age can be combined to predict mortality with a high level of specificity.
Whole genome sequencing (WGS) of
supports both molecular typing and detection of antimicrobial resistance (AMR). Here, we evaluated the correlation between phenotypic antimicrobial susceptibility ...testing (AST) and in silico prediction of AMR from WGS in
(
= 1321) isolated from human infections in Canada. Phenotypic AMR results from broth microdilution testing were used as the gold standard. To facilitate high-throughput prediction of AMR from genome assemblies, we created a tool called Staramr, which incorporates the ResFinder and PointFinder databases and a custom gene-drug key for antibiogram prediction. Overall, there was 99% concordance between phenotypic and genotypic detection of categorical resistance for 14 antimicrobials in 1321 isolates (18,305 of 18,494 results in agreement). We observed an average sensitivity of 91.2% (range 80.5-100%), a specificity of 99.7% (98.6-100%), a positive predictive value of 95.4% (68.2-100%), and a negative predictive value of 99.1% (95.6-100%). The positive predictive value of gentamicin was 68%, due to seven isolates that carried
, which conferred MICs just below the breakpoint of resistance. Genetic mechanisms of resistance in these 1321 isolates included 64 unique acquired alleles and mutations in three chromosomal genes. In general, in silico prediction of AMR in
was reliable compared to the gold standard of broth microdilution. WGS can provide higher-resolution data on the epidemiology of resistance mechanisms and the emergence of new resistance alleles.
The objective of the study was to determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) contamination of retail meat and to determine the level of contamination. Pork (pork ...chops and ground pork), ground beef and chicken (legs, wings and thighs) were purchased at retail outlets in four Canadian provinces and tested for the presence of methicillin-resistant Staph. aureus using qualitative and quantitative methods. MRSA was isolated from 9·6% of pork, 5·6% of beef and 1·2% of chicken samples (P = 0·0002). Low levels of MRSA were typically present, with 37% below the detection threshold for quantification and <100 CFU g⁻¹ present in most quantifiable samples. All isolates were classified as Canadian epidemic MRSA-2 (CMRSA-2) by pulsed field gel electrophoresis (PFGE), with two different PFGE subtypes, and were spa type 24/t242. MRSA contamination of retail meat is not uncommon. While CMRSA-2, a human epidemic clone, has been found in pigs in Canada, the lack of isolation of livestock-associated ST398 was surprising. The relevance of MRSA contamination of meat is unclear but investigation is required because of the potential for exposure from food handling. Sources of contamination require investigation because these results suggest that human or animal sources could be involved.
Forty-three isolates of the entomopathogenic fungus
Beauveria bassiana were screened for virulence against second-instar larvae of diamondback moth (
Plutella xylostella) (DBM), European corn borer (
...Ostrinia nubilalis) (ECB), corn earworm (
Helicoverpa zea) (CEW), and fall armyworm (
Spodoptera frugiperda) (FAW); 30 of these isolates were tested against beet armyworm (
Spodoptera exigua) (BAW). Highly virulent isolates were also tested against black cutworm (
Agrotis ipsilon) (BCW), and the most virulent isolate was also assayed against imported cabbage worm (
Pieris rapae) (ICW) and cabbage looper (
Trichoplusia ni) (CL). All lepidopteran species tested were susceptible to
B. bassiana. Corn earworm and beet armyworm were most susceptible to fungal infection, and fall armyworm was least susceptible. Limited testing suggested low susceptibility of black cutworm and cabbage looper.
B. bassiana isolate 1200 exhibited virulence against all pest species greater than or equal to commercial strain GHA of
B. bassiana currently registered in the USA as BotaniGard®. In assays in which larvae were topically sprayed and maintained on the treated substrate for 24
h at 100% relative humidity, 6-day (25
°C) median lethal concentrations (LC
50s) of this isolate against CEW, BAW, DBM, FAW, ICW, ECB, CL, and BCW were 4, 5, 7, 11, 12, 98, 125, and 273 conidia/mm
2, respectively. The respective LC
50s of commercial strain GHA against these pest species were 9, 67, 97, 1213, 29, 1668, 541, and 3504
conidia/mm
2. Use of LC
50 versus median lethal concentration ratios (comparing LC
50s of each isolate to a “standard” strain) generated similar rankings of isolate virulence. Results from parametric ANOVAs of log LC
50 values followed by Tukey HSD multiple comparisons tests and those from Kruskal–Wallis nonparametric analyses followed by sequential Bonferroni tests for means comparisons were nearly identical.
► M-phthalocyanine/fullerene devices in blended and bilayer structures. ► Blended monovalent and divalent M-Pc/C60 has improved exciton separation. ► Blended trivalent and tetravalent M-Pc/C60 has ...reduced hole transport efficiency. ► Grouping of device Voc by valency of central moiety.
Photovoltaic devices made from M-phthalocyanine and fullerene have been fabricated and characterized by current–voltage response, lateral time-of-flight photoconductivity, UV-visible absorption and scanning electron microscopy. The effect of varying the central moiety on the photovoltaic performance is examined, and demonstrates that the monovalent and divalent phthalocyanines tend to yield higher efficiencies in blended structures, whereas the trivalent and tetravalent phthalocyanines tend to yield higher efficiencies in a bilayer structure. The apparent reason for the disparity is the measured decrease in the hole transport efficiency in trivalent and tetravalent phthalocyanine upon blending with C60. Furthermore, the open circuit voltages of M-phthalocyanine/fullerene solar cells are grouped together according to the valency of the central moiety.
Extended-spectrum β-lactamases (ESBLs) confer resistance to extended-spectrum cephalosporins, a major class of clinical antimicrobial drugs. We used genomic analysis to investigate whether domestic ...food animals, retail meat, and pets were reservoirs of ESBL-producing Salmonella for human infection in Canada. Of 30,303 Salmonella isolates tested during 2012–2016, we detected 95 ESBL producers. ESBL serotypes and alleles were mostly different between humans (n = 54) and animals/meat (n = 41). Two exceptions were blaSHV-2 and blaCTX-M-1 IncI1 plasmids, which were found in both sources. A subclade of S. enterica serovar Heidelberg isolates carrying the same IncI1-blaSHV-2 plasmid differed by only 1–7 single nucleotide variants. The most common ESBL producer in humans was Salmonella Infantis carrying blaCTX-M-65, which has since emerged in poultry in other countries. There were few instances of similar isolates and plasmids, suggesting that domestic animals and retail meat might have been minor reservoirs of ESBL-producing Salmonella for human infection.
This study was designed to evaluate the prevalence of Clostridium difficile contamination of retail chicken. Chicken legs, thighs and wings were purchased using a standardized method from retail ...outlets across Ontario, Canada. Selective culture was used for qualitative and quantitative detection of C. difficile. Clostridium difficile was isolated from 26/203 (12·8%) chicken samples; 10/111 (9·0%) thighs, 13/72 (18%) wings and 3/20 (15%) legs (P = 0·19). All isolates were ribotype 078, a strain that has been associated with food animals and potentially community-associated disease in humans. All positive samples were positive only on enrichment culture. Clostridium difficile could be found relatively commonly in retail chicken meat, albeit at low levels. This is the first study to report C. difficile in chicken meat. Contamination of meat with C. difficile strains implicated in human infections raises concerns about food as a source of C. difficile infection. The relevance of food contamination is completely unclear at this point but food should be investigated as a source of infection.
Thin films of MoS2 bilayer nanoflakes, which are predominantly a single flake thick and with flakes in edge-to-edge contact, have been produced via self-assembled tiling at the planar interface ...between two immiscible liquids. Films of several square centimeters extent can be produced with a total covered area approaching 90% and over 70% of the film covered by single flakes without overlap. Films produced through liquid/liquid assembly are shown to produce a lower uncovered area fraction and more uniform thickness when compared with films of similar areal coverage produced by the “top-down” techniques of spin coating and spray coating. Statistical analysis of flake coverage data, measured by atomic force microscopy (AFM), shows that liquid/liquid assembly produces a distinctly different variation in film thickness than conventional top-down deposition. This supports the hypothesis that the two-dimensional (2D) confinement of liquid/liquid assembly produces more uniform films. Demonstrator field-effect transistors (FETs) manufactured from the films exhibit mobility and on/off current ratios of 0.73 cm2 V–1 s–1 and 105, respectively, comparable to FETs of similar layout and chemical vapor deposition (CVD)-grown or mechanically cleaved single-crystal MoS2 channel material. This work demonstrates the use of liquid/liquid interfaces as a useful tool for the self-assembly of high-performance thin-film devices made from dispersions of 2D materials.
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