Predicting likelihood of in vivo chemotherapy response in canine lymphoma using ex vivo drug sensitivity and immunophenotyping data in a machine learning model

We report a precision medicine platform that evaluates the probability of chemotherapy drug efficacy for canine lymphoma by combining ex vivo chemosensitivity and immunophenotyping assays with computational modelling. We isolated live cancer cells from fresh fine needle aspirates of affected lymph nodes and collected post‐treatment clinical responses in 261 canine lymphoma patients scheduled to receive at least 1 of 5 common chemotherapy agents (doxorubicin, vincristine, cyclophosphamide, lomustine and rabacfosadine). We used flow cytometry analysis for immunophenotyping and ex vivo chemosensitivity testing. For each drug, 70% of treated patients were randomly selected to train a random forest model to predict the probability of positive Veterinary Cooperative Oncology Group (VCOG) clinical response based on input variables including antigen expression profiles and treatment sensitivity readouts for each patient's cancer cells. The remaining 30% of patients were used to test model performance. Most models showed a test set ROC‐AUC > 0.65, and all models had overall ROC‐AUC > 0.95. Predicted response scores significantly distinguished (P < .001) positive responses from negative responses in B‐cell and T‐cell disease and newly diagnosed and relapsed patients. Patient groups with predicted response scores >50% showed a statistically significant reduction (log‐rank P < .05) in time to complete response when compared to the groups with scores <50%. The computational models developed in this study enabled the conversion of ex vivo cell‐based chemosensitivity assay results into a predicted probability of in vivo therapeutic efficacy, which may help improve treatment outcomes of individual canine lymphoma patients by providing predictive estimates of positive treatment response.     

Some chemical composition and biological activity of northern Argentine propolis

Twenty-five samples of propolis were collected from seven different regions in northern Argentina; ethanolic extracts of propolis were prepared from all samples, and the respective samples were examined for UV absorption spectra, RPHPTLC, RPHPLC, antimicrobial activity, antiradical activity, and total phenolic content. It was found that 16 of the 25 samples showed a phenolic profile similar to that found in samples from southern Brazil and corresponding to poplar-based propolis and that the rest of the samples showed a different profile and higher antimicrobial and antiradical activities.     

Preliminary analysis of recombinant β-tubulin of Pseudocohnilembus persalinus (Ciliophora: Scuticociliatida) as a vaccine antigen candidate against scuticociliatosis

The recombinant β-tubulin of Pseudocohnilembus persalinus was investigated to test whether tubulin could be a suitable antigenic target against scuticociliatosis. The cDNA of P. persalinus β-tubulin has an open reading frame of 1332 bp and had 15 TAA triplets code for glutamine (Q). All 15 TAA/Q triplets of the β-tubulin cDNA were mutated to universal CAA/Q triplets by site-directed mutagenesis and the mutated β-tubulin was expressed in Escherichia coli as a fusion with glutathione S-transferase (GST-BTU). In Western blot analysis, rat sera immunized with recombinant GST-BTU reacted with reduced β-tubulin of P. persalinus. The immunized rat sera showed higher parasiticidal activity than those of control. Ciliates preincubated with heat-inactivated immune sera showed significantly lower proliferation than ciliates preincubated with control sera when exposed to naïve rat sera as a complement source. The present results suggest that the recombinant β-tubulin of scuticociliates may be used as a target antigen for development of vaccine against scuticociliatosis.     

Development of an enzyme-linked immunosorbent assay for the detection of the fungicide fenarimol

To develop an enzyme-linked immunosorbent assay for the fungicide fenarimol, two synthesized haptens, haptens-1 and -2, and the purchased 4,4'-DDA were conjugated to carrier proteins (BSA, KLH, and OVA). Polyclonal antibodies raised against hapten-1,2-KLH conjugates in rabbits and the coating antigens of hapten-1,2-BSA conjugates, hapten-2-OVA conjugate, and 4,4'-DDA-BSA conjugate were screened and selected for the homologous and/or heterologous ELISA formats. Two competitive indirect ELISAs were selected: assays I and II. The optimized ciELISAs of assays I and II showed average IC(50) values of fenarimol of 5.4 and 9.4 ng/mL, detection ranges of 1.1-25.9 and 1.1-82.7 ng/mL, and lowest detection limits of 0.3 and 0.3 ng/mL, respectively. The cross-reactivities with several structurally related compounds indicated the importance of the steric fitness in the antigen-antibody interaction. Recoveries of fenarimol from apple and pear samples spiked with the analyte by assay I were in the range of 93-113% by simple extraction, concentration, and dilution. This assay could be a convenient and supplemental analytical tool for monitoring fenarimol residues in environmental and agricultural samples.     

Preparation, characteristics, and stability of glutathione-loaded nanoparticles

The aim of this study was to investigate the characteristics and oxidative stability of chitosan-glutathione conjugate (CS-GSH) and CS-GSH nanoparticles (CS-GSH NPs) to explore the potentials of these nanoparticle systems for GSH delivery. CS-GSH was synthesized using a radical polymerization method, and CS-GSH NP was prepared by ionic gelation of CS-GSH with sodium tripolyphosphate (TPP). The sizes of CS-GSH NPs significantly increased with increasing CS-GSH concentration and CS-GSH/TPP ratio. The entrapment efficiency (EE) significantly increased with increasing CS-GSH concentration and significantly decreased with increasing CS-GSH/TPP ratio. The immobilized GSH could be protected against oxidation compared to free GSH. The thiol content in the nanoencapsulated GSH was more effectively maintained than those in free GSH and CS-GSH, regardless of the presence of oxidative stress-inducing agents. These results suggest that CS-GSH NP can be used to enhance the oxidative stability of GSH.     

Benign masses in the pericardium of two dogs

Two miniature Schnauzer dogs were treated for pericardial masses. In one dog the mass consisted of necrotic fat that was attached to the apex of the pericardium by a pedicle. No obvious communication with the abdomen was present. The second dog had a peritoneopericardial hernia associated with a chronic cystic haematoma. In each case the mass was presumed to have arisen following congenital displacement of the omentum into the pericardium. The pericardial mass was removed and subtotal pericardectomy performed in both dogs. Recovery was complete in each case.     

Field comparison of the interferon-gamma assay and the intradermal tuberculin test for the diagnosis of bovine tuberculosis

An extensive field comparison of the gamma interferon (IFN-gamma) assay and the single intradermal tuberculin test for the diagnosis of bovine tuberculosis was conducted in Australia. The specificity of the IFN-gamma assay was determined by testing more than 6000 cattle from tuberculosis-free herds and varied from 96.2% to 98.1%, depending on the cut-off point chosen to define a positive reactor. For the sensitivity trial, cattle from herds being de-populated because of bovine tuberculosis were examined with both assays. The sensitivity of the IFN-gamma assay was shown to be significantly higher than the single intradermal tuberculin test and varied from 76.8% to 93.6% depending on the method of interpretation. A maximum overall sensitivity of 95.2% was obtained by testing with the IFN-gamma and the tuberculin test in parallel. The superior sensitivity of the IFN-gamma assay and the ability to adjust the sensitivity of the system depending on the task involved, will provide the Australian Tuberculosis Eradication Campaign with a valuable additional test to enable it to accomplish its goals.     

Effects of Dietary Chlorella ellipsoidea Supplementation on Growth, Blood Characteristics, and Whole-Body Composition in Juvenile Japanese Flounder Paralichthys olivaceus

The study was conducted to investigate the effects of dietary Chlorella powder (C) supplementation on growth performance, blood characteristics, and whole-body composition in juvenile Japanese flounder Paralichthys olivaceus . Four experimental diets were supplemented with C at 0, 1, 2 and 4% (C₀, C₁, C₂, and C₄) on a dry-weight basis. Three replicate groups of fish averaging 1.13 ± 0.02 g (Mean ± SD) were randomly distributed in each aquarium and fed one of four experimental diets for 12 wk. After 12 wk of the feeding trial, fish fed C₂ diet had higher weight gain (WG), feed efficiency (FE), and protein efficiency ratio (PER) than did fish fed C₀ and C₁ diets ( P 0.05); however, there was no significant difference among fish fed C₁ and C₄ diets, and among fish fed C₂ and C₄ diets ( P > 0.05). Fish fed C₂ and C₄ diets had a lower serum cholesterol level than did fish fed C₀ and C₁ diets ( P 0.05). Fish fed C₂ and C₄ diets had a lower body fat than did fish fed C₀ ( P 0.05). These results indicate that dietary supplementation of 2% Chlorella powder in the commercial diets could improve growth, feed utilization, serum cholesterol level, and whole-body fat contents in juvenile Japanese flounder.