Vasovagal tonus index (VVTI) as an indirect assessment of remission status in canine multicentric lymphoma undergoing multi-drug chemotherapy

Vasovagal tonus index (VVTI) is an indirect measure of heart rate variability and may serve as a marker of disease severity. Higher heart rate variability has predicted lower tumour burden and improved survival in humans with various tumour types. The purpose of this pilot study was to evaluate VVTI as a biomarker of remission status in canine lymphoma. The primary hypothesis was that VVTI would be increased in dogs in remission compared to dogs out of remission. Twenty-seven dogs were prospectively enrolled if they had a diagnosis of intermediate to high-grade lymphoma and underwent multidrug chemotherapy. Serial electrocardiogram data were collected under standard conditions and relationships between VVTI, remission status and other clinical variables were evaluated. VVTI from dogs in remission (partial or complete) did not differ from dogs with fulminant lymphoma (naive or at time of relapse). Dogs in partial remission had higher VVTI than dogs in complete remission (p = 0.021). Higher baseline VVTI was associated with higher subsequent scores (p < 0.001). VVTI also correlated with anxiety level (p = 0.03). Based on this pilot study, VVTI did not hold any obvious promise as a useful clinical biomarker of remission status. Further investigation may better elucidate the clinical and prognostic utility of VVTI in dogs with lymphoma

Distribution of myofibroblasts, smooth muscle-like cells, macrophages, and mast cells in mitral valve leaflets of dogs with myxomatous mitral valve disease

Objective—To map the cellular distribution and phenotypic alteration of the predominant stromal cell population throughout the entire valve length of dogs with myxomatous mitral valve disease (MMVD).<p></p> Sample Population—31 mitral valve complexes (ie, mitral valve leaflets) collected from 4 clinically normal dogs and 27 dogs with MMVD of varying severity.<p></p> Procedures—A combination of standard histologic and immunohistochemical techniques was used to identify pathologic changes, the presence of mast cells, and the density and distribution of cells expressing vimentin, desmin, A-smooth muscle actin (A-SMA), smooth muscle myosin, and the macrophage marker MAC387.<p></p> Results—Vimentin-positive cells predominated in the mitral valve leaflets from clinically normal dogs and were located throughout the leaflet, but cell density was appreciably decreased with disease progression, and minimal cell numbers were found in distinct myxomatous areas. Cells that were positive for A-SMA were uncommon in the mitral valve leaflets from clinically normal dogs and only seen in appreciable numbers in mitral valves of dogs with severe late-stage disease, in which cells were typically located close to the ventricularis valve surface. A slight increase in mast cell numbers was observed in the distal zone of affected leaflets.<p></p> Conclusions and Clinical Relevance—Activated-myofibroblasts (α-SMA–positive cells) were increased and inactive-myofibroblasts (vimentin-positive cells) were reduced in mitral valve leaflets of dogs with MMVD, compared with that of clinically normal dogs.<p></p> Impact on Human Medicine—This is the first description of spatial and temporal alterations in mitral valve cells of any species with MMVD and has clinical importance in the understanding of disease development in dogs and humans

Associations among echocardiography, cardiac biomarkers, insulin metabolism, morphology, and inflammation in cats with asymptomatic hypertrophic cardiomyopathy

Signaling is an important topic in the study of asymmetric information in economic settings. In particular, the transparency of information available to a seller in an auction setting is a question of major interest. We introduce the study of signaling when conducting a second price auction of a probabilistic good whose actual instantiation is known to the auctioneer but not to the bidders. This framework can be used to model impressions selling in display advertising. We establish several results within this framework. First, we study the problem of computing a signaling scheme that maximizes the auctioneer’s revenue in a Bayesian setting. We show that this problem is polynomially solvable for some interesting special cases, but computationally hard in general. Second, we establish a tight bound on the minimum number of signals required to implement an optimal signaling scheme. Finally, we show that at least half of the maximum social welfare can be preserved within such a scheme