Interventional Heartworm Extraction in Two Dogs: The Clinical Application of Impedance Cardiography.

Heartworm (HW) disease, caused by Dirofilaria immitis, is a life-threatening ailment in dogs. HW disrupts blood flow and decreases cardiac output (CO). The accurate monitoring of CO during HW extraction is pivotal for patient survival and overall health. OBJECTIVE: This study aimed to assess the efficacy of using impedance cardiography (ICG) as a non-invasive approach for monitoring CO during interventional HW extraction. METHODS: Two cases of HW infections were treated via surgical extraction. The CO and mean arterial pressure (MAP) were monitored using the ICG technique during the anesthesia stabilization, extraction process, and post-extraction phases. RESULTS: In Case 1, the CO increased by 115% post-procedure, and in Case 2, the CO increased by 116%. In contrast, the MAP varied between the two cases. The ICG method provided real-time CO data without major disruptions during the extraction surgery. CONCLUSION: The ICG technique for CO monitoring during interventional HW extractions is effective.

Feline adipose tissue-derived mesenchymal stem cells pretreated with IFN-γ enhance immunomodulatory effects through the PGE2 pathway.

BACKGROUND: Preconditioning with inflammatory stimuli is used to improve the secretion of anti-inflammatory agents in stem cells from variant species such as mouse, human, and dog. However, there are only few studies on feline stem cells. OBJECTIVES: This study aimed to evaluate the immune regulatory capacity of feline adipose tissue-derived (fAT) mesenchymal stem cells (MSCs) pretreated with interferon-gamma (IFN-γ). METHODS: To assess the interaction of lymphocytes and macrophages with IFN-γ-pretreated fAT-MSCs, mouse splenocytes and RAW 264.7 cells were cultured with the conditioned media from IFN-γ-pretreated MSCs. RESULTS: Pretreatment with IFN-γ increased the gene expression levels of cyclooxygenase-2, indoleamine 2,3-dioxygenase, hepatocyte growth factor, and transforming growth factor-beta 1 in the MSCs. The conditioned media from IFN-γ-pretreated MSCs increased the expression levels of M2 macrophage markers and regulatory T-cell markers compared to those in the conditioned media from naive MSCs. Further, prostaglandin E2 (PGE2) inhibitor NS-398 attenuated the immunoregulatory potential of MSCs, suggesting that the increased PGE2 levels induced by IFN-γ stimulation is a crucial factor in the immune regulatory capacity of MSCs pretreated with IFN-γ. CONCLUSIONS: IFN-γ pretreatment improves the immune regulatory profile of fAT-MSCs mainly via the secretion of PGE2, which induces macrophage polarization and increases regulatory T-cell numbers.