Background Babesia canis infection induces a marked acute phase response (APR) that might be associated with alteration in lipid and lipoprotein metabolism and disease prognosis. Hypothesis Dogs with B. canis‐induced APR develop dyslipidemia with altered lipoprotein concentration and morphology. Animals Twenty‐nine client‐owned dogs with acute B. canis infection and 10 clinically healthy control dogs. Methods Observational cross‐sectional study. Serum amyloid A (SAA) was measured using ELISA. Cholesterol, phospholipids, and triglycerides were determined biochemically. Lipoproteins were separated using agarose gel electrophoresis. Lipoprotein diameter was assessed by polyacrylamide gradient gel electrophoresis; correlation with ApoA‐1 (radioimmunoassay) and SAA was determined. Results Dogs with B. canis infection had a marked APR (median SAA, 168.3 μg/mL; range, 98.1‐716.2 μg/mL) compared with controls (3.2 μg/mL, 2.0‐4.2 μg/mL) (P < .001). Dogs with B. canis infection had significantly lower median cholesterol (4.79 mmol/L, 1.89‐7.64 mmol/L versus 6.15 mmol/L, 4.2‐7.4 mmol/L) (P = .02), phospholipid (4.64 mmol/L, 2.6‐6.6 mmol/L versus 5.72 mmol/L, 4.68‐7.0 mmol/L) (P = .02), and α‐lipoproteins (77.5%, 27.7%‐93.5% versus 89.2%, 75.1%‐93.5%) (P = .04), and higher ApoA‐1 (1.36 U, 0.8‐2.56 U versus 0.95 U, 0.73‐1.54 U) concentrations (P = .02). Serum amyloid A correlated with high‐density lipoproteins (HDLs) diameter (rho = .43; P = .03) and ApoA‐1 (rho = .63, P < .001). Conclusions and Clinical Importance Major changes associated with B. canis‐induced APR in dogs are related to concentration, composition, and morphology of HDL particles pointing to an altered reverse cholesterol transport. Parallel ApoA‐1 and SAA concentration increase is a unique still unexplained pathophysiological finding.

As an alternative to classical brachytherapy, intratumoral injection of radionuclide-labeled nanoparticles (nanobrachytherapy, NBT) has been investigated as a superior delivery method over an intravenous route for radionuclide therapy of solid tumors. We created superparamagnetic iron oxide nanoparticles (SPIONs) coated with meso-1,2-dimercaptosuccinic acid (DMSA) and radiolabeled with Lutetium-177 (¹⁷⁷Lu), generating ¹⁷⁷Lu-DMSA@SPIONs as a potential antitumor agent for nanobrachytherapy. Efficient radiolabeling of DMSA@SPIONS by ¹⁷⁷Lu resulted in a stable bond with minimal leakage in vitro. After an intratumoral injection to mouse colorectal CT-26 or breast 4T1 subcutaneous tumors, the nanoparticles remained well localized at the injection site for weeks, with limited leakage. The dose of 3.70 MBq/100 µg/50 µL of ¹⁷⁷Lu-DMSA@SPIONs applied intratumorally resulted in a high therapeutic efficacy, without signs of general toxicity. A decreased dose of 1.85 MBq/100 µg/50 µL still retained therapeutic efficacy, while an increased dose of 9.25 MBq/100 µg/50 µL did not significantly benefit the therapy. Histopathology analysis revealed that the ¹⁷⁷Lu-DMSA@SPIONs act within a limited range around the injection site, which explains the good therapeutic efficacy achieved by a single administration of a relatively low dose without the need for increased or repeated dosing. Overall, ¹⁷⁷Lu-DMSA@SPIONs are safe and potent agents suitable for intra-tumoral administration for localized tumor radionuclide therapy.

Calf bronchopneumonia is complex multifactorial disease and for its accurate diagnosis and therapy, besides clinical examination, microbiologic, hematologic and biochemical analyses could be necessary. In general, additional analyses are not implemented, mainly because the disease biomarkers are not defined.To establish which analysis might be useful for determining the severity of the disease, we analyzed 23 three-month old calves with mild clinical signs of bronchopneumonia and 15 age-matched healthy calves.Pasteurella multocidawas isolated from deep nasal swabs of diseased calves. Peripheral blood erythrocyte and leukocyte count of bronchopneumonic and healthy calves showed no difference. Serum proteins, lipoproteins and lipids were analyzed with spectrophotometry, agarose gel electrophoresis, non-reducing SDS-PAGE, gel zymography, and thin-layer chromatography. The bronchopneumonic calves had an increased level of circulating immune complexes and α globulins, which contain some of the positive acute phase proteins. In diseased calves the increased concentration of total γ globulins (IgG), due to an increased concentration of anionic γ globulins (predominately IgG1), was detected. The increased concentration of anionic γ globulins followed by increased concentration of transferrin (negative acute phase protein) and HDL cholesterol, decreased concentration of LDL-cholesterol, unchanged activity of matrix metalloproteases and leukocyte counts might reflect the obvious absence of generalized inflammation. A positive correlation was found between the acquired results and the appearance of mild clinical signs. Therefore, we believe that the parameters analyzed in the peripheral blood could be applied as reliable disease markers to distinguish between severe (inflammatory) and mild forms of calf bronchopneumonia and to predict a better outcome for these calves.

Application of bone-seeking radiopharmaceuticals is one of the modalities in the management of metastatic bone pain. The present study aimed to investigate the potential of ¹⁷⁷Lu-labeled phosphate/phosphonate ligands: 1-hydroxyethane 1,1-diphosphonic acid (HEDP), 2,3-dicarboxypropane-1,1-diphosphonic acid (DPD), and imidodiphosphate tetrasodium salt (IDP), as bone pain palliation agents. HEDP, DPD, and IDP were radiolabeled with ¹⁷⁷Lu in high radiolabeling yield (98.49%, 93.31%, and 90.69%, respectively), forming in vitro stable radiolabeled complexes in saline and human serum after 96 h. Biodistribution was followed by imaging studies and ex vivo measurement of radioactivity in organs in healthy Wistar rats. Significant bone accumulation and long retention even after 96 h (3.85 ± 0.91%ID/g), as well as relatively low uptake in soft tissue such as liver and spleen (<1%ID/g), were observed for ¹⁷⁷Lu-HEDP. Two other radiolabeled ligands showed lower accumulations in bone (1.5% ID/g). Obtained results suggest that difference in the chemical structure of phosphonates/phosphates influences the rate of bone incorporation of ¹⁷⁷Lu-radiolabeled complexes. Desirable biodistribution pattern of ¹⁷⁷Lu-HEDP makes it suitable for its further preclinical investigations as a potential bone pain palliation agent.