Search Results (266)

Liquid biopsy offers dynamic and noninvasive analysis of cellular biomarkers, thereby presenting enormous potential for early detection of cancer, cancer staging, prediction of relapse, real-time examination of therapeutic efficacy, perception of therapeutic targets, and understanding the resistance mechanisms. Nanotechnology has emerged as a novel tool to widen the application horizon of liquid biopsy. Several nanomaterials, nanodevices, nanostructures, and nanosensors have been explored for improved application of liquid biopsy for biomarker detection. The circulating tumor cells (CTCs), circulating tumor proteins (CTP), miRNA and extracellular vesicles (EVs) are some of the important biomarkers for detection by liquid biopsy in bodily fluids. Herein, we have discussed the state of the art and beyond in advances in nanotechnology and in increasing the specificity, sensitivity, and purity with which we detect liquid biopsy biomarkers. The opportunities and prospects of these advanced innovative nanomaterials and technologies in clinical applications are explored. Furthermore, various isolation and biosensing strategies for visualization and signal amplification using nanomaterials are summarized. The utilization of nanotechnology-based liquid biopsy may provide greater insights for improved treatment, diagnosis, and prognosis of cancer. Full article

Radiofrequency ablation (RFA) and pulsed radiofrequency (PRF) are non-pharmacological techniques employed in humans for chronic pain, but their veterinary application is unexplored. This pilot study evaluated clinical effects of RFA and PRF in twenty-four horses with chronic distal forelimb lameness. Ultrasound-guided RFA (N = 8; 60–90 °C, 2–8 min) or PRF (N = 16; 42 °C; 12 min) was applied to palmar digital nerves. Lameness was scored (American Association of Equine Practitioners scale) at baseline and monthly for six months (T1-T6). At T2, partial- and non-responders in both groups received PRF. Complications and return to previous work were recorded. At T2, the PRF group had significantly lower lameness scores (1, 0–3) than the RFA group (3, 2–4; p < 0.001) and significantly improved from baseline (3, 2–4; p < 0.01). RFA caused more complications (N = 6) than PRF (N = 1; p < 0.001), including increased lameness and allodynia. Sixteen horses (RFA: N = 7; PRF: N = 9) were retreated at T2. Overall, lameness significantly improved from T2 (2, 0–4) to T6 (0, 0–3; p < 0.001). At T6, 83% (19/23) of horses resumed previous work. RFA was ineffective and caused complications, whereas PRF appeared safer and more effective. Two PRF treatments yielded better outcomes with fewer side effects and may help manage lameness and associated pain for up to six months. Full article

Chilean Schinus molle has been used in traditional medicine for effects such as antibacterial, antifungal, anti-inflammatory, analgesic, antiviral, antitumoral, antioxidant, antispasmodic, astringent, antipyretic, cicatrizant, cytotoxic, diuretic, among others. In this study, we evaluated the pharmacological potential of Schinus molle seed essential oil extract (SM_EO) through in vitro and in silico approaches. In vitro, the antioxidant potential was analyzed, and antitumor activity was evaluated in non-tumor and human epithelial tumor cell lines. Caenorhabditis elegans was used as a model for evaluating toxicity, and the chemical composition of the SM_EO was analyzed using gas chromatography–mass spectrometry. The oil contained four major monoterpenes: α-phellandrene (34%), β-myrcene (23%), limonene (13%), and β-phellandrene (7%). Based on quantum mechanical calculations, the reactivity of the molecules present in the SM_EO was estimated. The results indicated that α- phellandrene, β-phellandrene, and β-myrcene showed the highest nucleophilic activity. In addition, the compounds following these as candidates for antioxidant and antiproliferative activities were α-phellandrene, β-phellandrene, ρ-cymene, sabinene, caryophyllene, l-limonene, and α-pinene, highlighting β-myrcene. Based on ADME-Tox properties, it is feasible to use these compounds as new drug candidates. Moreover, the antibacterial activity MIC value obtained for B. cereus was equivalent to 2 μg/mL, and for Y. enterocolitica, S. enteritidis, and S. typhimurium, the MIC value was 32.5 μg/μL. SM_EO could selectively inhibit the proliferation of human epithelial mammary tumor MCF7 cells treated with SM_EOs at 64 and 16 ug/mL—a significant increase in BCL-2 in a dose-dependent manner—and showed low toxicity against Caenorhabditis elegans (from 10 to 0.078 mg·mL⁻¹). These findings suggest that SM_EO may be a potential source of bioactive compounds, encouraging further investigation for applications in veterinary medicine, cosmetics, and sanitation. Full article

Avian influenza A viruses (IAVs) pose a persistent threat to the poultry industry, causing substantial economic losses. Although traditional vaccines have helped reduce the disease burden, they typically rely on multivalent antigens, emphasize humoral immunity, and require intensive production. This study aimed to establish a genetically matched host–cell system to evaluate antigen-specific immune responses and identify conserved CD8+ T cell epitopes in avian influenza viruses. To this end, we developed an MHC class I genotype (B21)-matched host (Lohmann VALO SPF chicken) and cell vector (DF-1 cell line) model. DF-1 cells were engineered to express the hemagglutinin (HA) gene of clade 2.3.4.4b H5N1 either transiently or stably, and to stably express the matrix 1 (M1) and nucleoprotein (NP) genes of A/chicken/South Korea/SL20/2020 (H9N2, Y280-lineage). Following prime-boost immunization with HA-expressing DF-1 cells, only live cells induced strong hemagglutination inhibition (HI) and virus-neutralizing (VN) antibody titers in haplotype-matched chickens. Importantly, immunization with DF-1 cells transiently expressing NP induced stronger IFN-γ production than those expressing M1, demonstrating the platform’s potential for differentiating antigen-specific cellular responses. CD8+ T cell epitope mapping by mass spectrometry identified one distinct MHC class I-bound peptide from each of the HA-, M1-, and NP-expressing DF-1 cell lines. Notably, the identified HA epitope was conserved in 97.6% of H5-subtype IAVs, and the NP epitope in 98.5% of pan-subtype IAVs. These findings highlight the platform’s utility for antigen dissection and rational vaccine design. While limited by MHC compatibility, this approach enables identification of naturally presented epitopes and provides insight into conserved, functionally constrained viral targets. Full article

The last decades of research have shown that the endocannabinoid system may be a promising therapeutic target for the pharmacological treatment of cancer in human medicine and possibly in veterinary medicine as well. Compared with the original cells, the expression of gene encoding for receptors and enzymes belonging to the endocannabinoid system has been found to be altered in several tumor types; it has been hypothesized that this aberrant expression may be related to the course of the neoplasm as well as to the patient’s prognosis. Several studies, conducted both in vitro and in vivo, suggest that both endo- and phytocannabinoids can modulate signaling pathways, controlling cell proliferation and survival. In the complex process of carcinogenesis, cannabinoids seem to intervene at different levels by stimulating cell death, inhibiting the processes of angiogenesis and metastasis, and regulating antitumor immunity. Although the molecular mechanisms by which cannabinoids act are not always clear and defined, their synergistic activity with the most used antineoplastic drugs in clinical oncology is showing promising results, thus providing veterinary medicine with alternative therapeutic targets in disease control. This review aims to summarize current knowledge on the potential role of the endocannabinoid system and exogenous cannabinoids in oncology, with specific reference to the molecular mechanisms by which cannabinoids may exert antitumor activity. Additionally, it explores the potential synergy between cannabinoids and conventional anticancer drugs and considers their application in veterinary oncology. Full article

This study aimed to investigate the effect of gender on the pharmacokinetics of meloxicam in goats following intravenous (IV, 0.5 mg/kg) and oral (PO, 1.0 mg/kg) administration. A crossover design was used with 12 clinically healthy Saanen goats (six females and six males). Plasma samples were collected up to 96 h post-administration and analyzed with an HPLC for meloxicam concentrations. Pharmacokinetic parameters were calculated and statistically compared between genders and administration routes. The results show that male goats exhibited significantly longer terminal half-life (T_1/2λz), a greater mean residence time (MRT_0–∞), and higher systemic exposure (AUC_0–∞) than females, particularly after oral administration. Oral bioavailability was calculated as 77.43% in females and 104.73% in males. These differences may be linked to gender-based variations in hepatic metabolism, enterohepatic recirculation, and the hormone-mediated modulation of cytochrome P450 activity. The findings are consistent with previous research demonstrating that gender can influence drug disposition through hormonal and enzymatic mechanisms. This study underscores the importance of considering gender as a biological variable in pharmacokinetic assessments of veterinary drugs, especially those used in food-producing animals, to optimize dosing strategies and ensure both therapeutic efficacy and food safety. Full article

Naturally occurring prostaglandin E₂ (PGE₂) influences cytokine production regulation in bovine neutrophils exposed to Staphylococcus aureus Rosenbach. Here, we employed bovine neutrophils as the primary experimental system, and administered specific inhibitors targeting various receptors, which were subsequently exposed to S. aureus. Cytokine expression levels in dairy cow neutrophils induced by S. aureus via the endogenous PGE₂-EP2/4 receptor pathway were investigated, and its effects on P38, extracellular signal-regulated kinase (ERK), P65 activation, and phagocytic function in Staphylococcus aureus Rosenbach-induced dairy cow neutrophils, were examined. Blocking cyclooxygenase-2 (COX-2) and microsomal prostaglandin E synthase-1 (mPGES-1) enzymes substantially decreased PGE₂ production and release in S. aureus-exposed bovine neutrophils. Cytokine output showed significant reduction compared to that in SA113-infected controls. Phosphorylation of P38, ERK, and P65 signaling molecules was depressed in the infected group. Pharmacological interference with EP2/EP4 receptors similarly diminished cytokine secretion and phosphorylation patterns of P38, ERK, and P65, with preserved cellular phagocytic function. During S. aureus infection of bovine neutrophils, COX-2 and mPGES-1 participated in controlling PGE₂ biosynthesis, and internally produced PGE₂ molecules triggered NF-κB and MAPK inflammatory pathways via EP2/EP4 receptor activation, later adjusting the equilibrium between cytokine types that promote or suppress inflammation. This signaling mechanism coordinated inflammatory phases through receptor-mediated processes. Full article

Background/Objectives: Ceftiofur hydrochloride (CEF) is a third-generation cephalosporin widely used in cattle to treat various disease. The recommended dosage was 1.1 to 2.2 mg/kg BW for 3 to 5 consecutive days by intramuscular or subcutaneous injection. Incomplete treatment, overuse, or misuse, often observed in clinical practice, are major contributors to resistance development. This study aims to explore how different concentrations, durations, and dosing frequencies affect susceptibility and bactericidal efficacy of Staphylococcus aureus to optimize CEF dosage regimens. Methods: First, CEF was intermittently administered at 1/2 × minimum inhibitory concentration (MIC), 2 × MIC, 6 × MIC, and 100 × MIC for 30 cycles. Second, CEF was continuously administered for 48, 72, 96, 120, 144, and 168 h. Bacterial susceptibility, regrowth, survival rate, and the emergence of persisters or tolerant phenotypes were assessed. Genetic mutations were identified by whole-genome resequencing. Membrane permeability, integrity, and efflux pump activity were analyzed to elucidate the mechanism of CEF. Results: After 30 cycles, the MIC increased eight-fold in the 2 × MIC group. No significant MIC increase was found in other groups, but a progression from susceptibility to persistence and then to tolerance was observed in the 100 × MIC intermittent group. The survival rate increased both in the 2 × MIC and 100 × MIC groups. With continuous exposure to ≥6 × MIC over 120 h, strains were completely eradicated without MIC increase. Resistance-associated single-nucleotide polymorphism (SNP) mutations were detected only in strains of the 2 × MIC and 100 × MIC intermittent groups. CEF altered the membrane hydrophobicity, damaging membrane integrity after 30 cycles. Conclusions: These findings suggest that high-dose, prolonged exposure is more effective for eliminating Staphylococcus aureus and avoiding resistance, whereas intermittent dosing may promote persistence, tolerance, and resistance evolution. Full article

Propolis is a natural resinous substance produced by honeybees that has many biological activities. For thousands of years, it has been widely used as a dietary supplement and traditional medicine to treat a variety of ailments due to its antimicrobial, anti-inflammatory, antioxidant, immunomodulatory, and wound-healing properties. Nutritional supplements and foods may interact with drugs both pharmacodynamically and pharmacokinetically, which could raise clinical concerns. Background/Objectives: This study aimed to investigate the effect of propolis on the plasma disposition of enrofloxacin and to assess the potential pharmacokinetic interaction in rabbits. Methods: In this study, enrofloxacin was applied per os (20 mg/kg) and IM (10 mg/kg) and with propolis (100 mg resin/kg) administration in four groups of rabbits (each of six individuals). Heparinized blood samples were collected at 0, 0.1, 0.3, 0.5, 1, 2, 4, 8, 12, and 24 h post-administration. HPLC-FL was used to analyze the plasma concentrations of enrofloxacin and its active metabolite ciprofloxacin following liquid–liquid phase extraction, i.e., protein precipitation with acetonitrile and partitioning with sodium sulfate. Results: The results revealed that propolis coadministration significantly affected the plasma disposition of enrofloxacin and its active metabolite after both per os and intramuscular administration routes. Significantly greater AUC (48.91 ± 11.53 vs. 26.11 ± 12.44 µg.h/mL), as well as longer T_1/2λz (11.75 ± 3.20 vs. 5.93 ± 2.51 h) and MRT (17.26 ± 4.55 vs. 8.96 ± 3.82 h) values of enrofloxacin and its metabolite ciprofloxacin, were observed after the coadministration of propolis compared to enrofloxacin alone following both per os and IM routes in rabbits. Conclusions: The concurrent use of propolis and prescription medications may prolong the half-life (T_1/2λz) and increase the systemic availability of chronically used drugs with narrow therapeutic indices. The repeated use of drugs such as antibiotics, heart medications, and antidepressants, or drugs with a narrow therapeutic index such as antineoplastic and anticoagulant agents, can cause toxic effects by raising blood plasma levels. Considering the varied metabolism of rabbits and humans, further validation of this study may require thorough clinical trials in humans. Full article

The pleuromutilin derivative, the compound PL-W, was synthesized by introducing a 4-fluorophenyl group at the C21 position and selected for comprehensive antibacterial evaluation. PL-W demonstrated notable antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), with a minimum inhibitory concentration (MIC) of 0.03125 µg/mL, which is significantly lower than that of tiamulin (0.5 µg/mL). Crystal violet (CV) staining revealed that it inhibited MRSA biofilm formation and electron microscopy revealed that it disrupted bacterial cell division and, possibly, the synthesis of essential cell wall proteins. In both in vivo models, PL-W exhibited excellent performance. In the Galleria mellonella infection model, treatment with different concentrations of PL-W increased the survival rate from 20% to 90% and significantly reduced the bacterial load. In the mouse model of MRSA pneumonia, a 10 mg/kg dose of PL-W increased the survival rate to 70%, decreased the bacterial load in the lungs, and alleviated inflammatory damage. Molecular docking studies indicated that PL-W had a similar docking pose and comparable binding affinity to that of lefamulin, with hydrogen bond interactions that are crucial for binding to the peptidyl transferase center (PTC). Moreover, it demonstrated no significant reduction in cell viability in HepG2 and HEK293 cells, even at high concentrations (≤50 µg/mL). Overall, PL-W shows significant potential as a novel anti-MRSA agent owing to its potent in vitro and in vivo activities and low cytotoxicity. Full article

Toxoplasma gondii is a globally significant zoonotic pathogen responsible for severe parasitic diseases in humans and animals. This study aimed to design, develop, and evaluate a novel immunochromatographic test (ICT) using a recombinant MIC2-MIC3 fusion protein (rMIC2-MIC3) for detecting specific antibodies against T. gondii. The ICT demonstrated exceptional sensitivity, capable of detecting T. gondii-specific antibodies in sera diluted up to 1:8. Specificity evaluation confirmed no cross-reactivity with antibodies against other parasites, such as Neospora caninum, Cryptosporidium suis, Eimeria tenella, and Sarcocystis tenella. Stability tests revealed the test strips maintained full functionality after 12 weeks of storage at 24 °C. The coincidence rate of the colloidal gold test strips prepared in this study with a commercial ELISA kit was 94.59%. Comparisons with advanced serodiagnostic tools, such as chimeric antigen-based ELISAs and recombinant protein diagnostics, further highlighted its robustness and applicability. These findings underscore the potential of the rMIC2-MIC3-based ICT as a reliable, economical, and accessible diagnostic tool for toxoplasmosis in veterinary and human medicine. Full article

Dried blood spot (DBS) sampling has emerged as a promising microsampling technique in biomedical and clinical research, offering advantages such as reduced invasiveness, minimal blood volume requirements, and enhanced analyte stability. Although well established in human medicine for neonatal screening and diagnostic applications, its potential in veterinary pharmacology remains underexplored. This study investigated the feasibility of using DBS samples to quantify anesthetic agents—ketamine and medetomidine in cats and lidocaine in horses—during routine surgical procedures at a veterinary teaching hospital. A standardized DBS collection protocol was developed, and LC-MS/MS methods were validated for the quantification of target analytes in both DBS and plasma samples. These methods were subsequently applied to real samples collected during anesthesia to conduct pharmacokinetic analyses. Comparative evaluations, including Bland–Altman analysis, assessed the suitability of DBS samples for pharmacokinetic studies in veterinary medicine. Preliminary results indicated satisfactory agreement for medetomidine, meeting EMA guidelines, with 75.6% of mean values falling within ±20% of paired measurements. Results for ketamine (46.9%) were promising but require further optimization, while those for lidocaine (21.4%) highlighted the need for additional investigation. These findings underscore the potential of DBS sampling as a minimally invasive alternative for pharmacokinetic studies in veterinary medicine, particularly for medetomidine, while identifying areas for further methodological refinement. Future research should optimize DBS techniques and expand their application to other drugs and species, broadening their impact on veterinary pharmacology. Full article

Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors that develop in the gastrointestinal tract; KIT mutations are present in both canine and human GISTs. In this study, genomic DNA was extracted from formalin-fixed paraffin-embedded (FFPE) sections of 55 canine GIST cases, and mutation searches were performed for exons 8, 9, and 11. The results revealed novel mutations, A434T and F436S, in exon 8. In contrast to the A434T mutation without functional changes, the F436S mutant retained its dimerization ability, but lost its phosphorylation function and attenuated downstream Akt signaling, which is reflected in wound healing and migration activities. A comparison of the subcellular localization of WT KIT and the F436S mutant revealed no differences. In silico simulations indicated that the F436S mutation alters the structure of the near-membrane region and that its effects may extend to the transmembrane and intracellular domains compared to the WT. F436S is a point mutation that affects the entire molecule because co-mutation with the F436S mutation and the known autophosphorylation mutation reduces the autophosphorylation abilities. Full article

Introduction: Tylosin, a veterinary antimicrobial belonging to the macrolide family, is commonly used in the poultry industry. Residues generated from its use can be present in the litter and droppings of treated birds. Due to the diverse uses of poultry byproducts, such as fertilizing agricultural soils or incorporation into the diets of other animal species, there is a risk to public health, as the presence of antimicrobial residues favors the development of antimicrobial resistance, which is a global problem. Objective: This study aimed to evaluate the dissemination of tylosin residues from the litter and droppings of treated birds and untreated birds in a controlled broiler environment. Methods: Bird droppings and litter samples were collected and analyzed using HPLC-MS/MS to detect and quantify tylosin residues. Results: The residue concentrations detected in the dropping matrix only exceeded the Limits of Quantification (LOQ = 4 µg kg⁻¹) in the treated group. The litter matrix had statistically significant differences between the study groups. The persistence of tylosin residues in the litter of birds at day 42 was 290.16 µg kg⁻¹ in the treated group (A) and 9.35 µg kg⁻¹ in the adjacent untreated group (B.1). Conclusions: The results indicate that exposure distance influences tylosin residue dissemination. Full article

It is essential to establish a normative framework that ensures the harmonious coexistence of humans and animals from legal and institutional perspectives. This study classifies and compares animal welfare policies in welfare states, identifying distinct policy types across different countries. Using fuzzy set ideal type analysis, this study examines seven OECD countries: Austria, Denmark, Germany, South Korea, Sweden, the United Kingdom (UK), and the United States (USA). These countries are consistent with Esping-Andersen’s three welfare state models and actively implement animal welfare policies. This study addresses the limitations of previous studies that focused primarily on animal-related discourses by examining the characteristics of different policy types that integrate two core components of animal welfare policy: animal welfare law and animal welfare systems. This analysis identified four types of animal welfare policies: (1) economic value type (South Korea and the USA); (2) social value type (the UK); (3) rights extension type (Denmark, Germany, and Sweden); and (4) ecological type (Austria). The results show that welfare state animal welfare policies are generally consistent with the ideological characteristics of the welfare system in question. However, Korea presents notable differences, providing valuable insights into its unique approach to animal welfare policy and informing future policy development. Full article