Effects of topical ketorolac tromethamine on tear parameters, meibography, goblet cell density, and conjunctival oxidative stress in healthy dogs.

OBJECTIVES: The objective of the study was to evaluate whether a twice-daily instillation of 0.45% preservative-free ketorolac tromethamine (FKT) or 0.4% benzalkonium chloride-preserved ketorolac tromethamine (BACKT), every 12 h for 30 days may affect tear film parameters and the meibography in healthy dogs. Additionally, we assessed whether the same treatments irritated the ocular surface, affected goblet cell density (GCD), and the levels of oxidative stress biomarkers (OSB) in the conjunctiva of the same dogs. PROCEDURES: Experimental and masked comparison study. In 11 healthy dogs baseline values of the lipid layer thickness, tear meniscus height, non-invasive tear breakup time (NI-TFBT), and the meibomian gland (MG) loss were assessed by OSAvet®. For each dog, one eye received 40 µL of BACKT, while the other received 40 µL FKT, every 12 h for 30 consecutive days. Tear parameters and meibography were repeated 15, 30, and 60 days post-treatments. Conjunctival hyperemia and blepharospasm were monitored at the same time points. At baseline and Day 30, a conjunctival biopsy was collected for GCD and OSB determination. RESULTS: Conjunctival hyperemia and blepharospasm were not observed. At Day 15, the MG loss increased only in FKT-treated eyes (p < .001). On Day 30, both treatment groups showed increased MG loss, shortened NI-TFBT, and reduced GCD and catalase (p < .05). At Day 30, BACKT-treated eyes showed lower levels of superoxide dismutase (SOD) (p = .006) and higher levels of malondialdehyde (MDA) (p = .02). Differences between treatments were not observed for any parameter at any time point (p > .05). 60 days after treatment, OSAvet® parameters tended to return to values assessed at baseline; however, significant differences remained for MG loss (p < .05). CONCLUSIONS: Twice-daily instillation of KT, containing or not BAC, for 30 consecutive days shortened NI-TFBT, decreased GCD, and increased the MG loss in healthy dogs. KT should be used with caution when prescribed for long periods, particularly in patients with tear film abnormalities. However, future controlled studies using KT, BAC, and other topical NSAIDs are indicated to further support this finding.

Urethral catheterization after pharmacological induction for semen collection in dog.

The α-adrenergic agents are known to influence erection and ejaculation, and ejaculatory reflex is a primarily α-adrenergically mediated event. This paper aims to describe the urethral catheterization technique after pharmacological induction for semen collection in domestic dogs. For dose determination, semen collection was performed using increasing doses of dexmedetomidine (5 µg/kg, n = 2; 10 µg/kg, n = 2 and 15 µg/kg, n = 2) associated to 3 mg/kg ketamine in six animals. Once the dose was established, additional semen collection using association of 15 µg/kg dexmedetomidine and 3 mg/kg ketamine was carried out in eight dogs. After the procedure, sperm volume (0.092 ± 0.03 mL), total motility (58.33 ± 8.7%), vigor (1.89 ± 0.309), sperm concentration (1186.67 ± 304.667 × 106 sperm/mL), sperm plasma membrane integrity (83.22 ± 4.82%), acrosomal integrity (73 ± 6.187%) and normal sperm morphology (53.22 ± 5.6%) were assessed. Thus, this study demonstrates that urethral catheterization after pharmacological ejaculation using dexmedetomidine-ketamine association can be performed in dogs and it may be possible to obtain good semen quality, despite urine contamination.

Síntese e caracterização de nanopartículas de ouro conjugadas com curcumina e seus efeitos na osteoartrite experimental induzida / Synthesis and characterization of gold nanoparticles combined with curcumin and its effects on experimentally induced osteoarthritis

RESUMO: A Osteoartrite (OA) é uma denominação clínica para uma combinação de condições patológicas que envolvem a degeneração progressiva da cartilagem articular e remodelação de osso subcondral. A curcumina, um potente agente anti-inflamatório, têm sido extensivamente estudada, no entanto não oferece boa biodisponibilidade sistêmica. Nanopartículas de ouro (AuNPs) apresentam aplicações potenciais na administração de substâncias terapêuticas aumentando a eficiência do transporte de fármacos. O objetivo deste estudo foi realizar a síntese e caracterização de um sistema conjugando as AuNPs à curcumina e avaliar seu potencial terapêutico em um modelo experimental de OA em camundongos por desestabilização do menisco medial (DMM). As AuNPs foram conjugadas com curcumina e os sistemas foram caracterizados por espectroscopia no UV-VIS, espalhamento de luz dinâmico (DLS) e determinação do potencial zeta. Formou-se 4 grupos de oito animais cada, denominados A, B, C, D que receberam injeção intra-articular de AuNPs, curcumina, AuNP-curcumina e solução fisiológica, respectivamente. Após 7 semanas, a cartilagem da articulação-femoro- tibio-patelar (AFTP) foi avaliada em uma variação de escore de 0 a 24. A conjugação de AuNP-curcumina mostrou boa estabilidade e aplicação terapêutica, mas não diferiu significativamente (P>0,05) dos grupos A e B, no entanto, mostrou menor valor de escore e significância (P<0,001) em relação ao grupo controle. Os resultados deste trabalho mostram a importância do desenvolvimento de novos nanofármacos. Neste caso a conjugação de AuNPs com a curcumina permitiu a obtenção de um nanofármaco com sugestivo potencial para aplicação no tratamento da OA.

ABSTRACT: Osteoarthritis (OA) is the clinical term for a combination of pathological conditions that involve the progressive degeneration of articular cartilage and subchondral bone remodelling. Curcumin, a potent anti-inflammatory agent, has been extensively studied; however, it does not provide good systemic bioavailability. Gold nanoparticles (AuNPs) have potential applications in the administration of therapeutic substances in order to increase the transport efficiency of drugs. The objectives of this study were to explore the synthesis and characterization of a system combining AuNPs with curcumin and evaluate its therapeutic potential in an experimental model of OA in mice by the destabilization of the medial meniscus (DMM). The AuNPs were conjugated with curcumin and the systems were characterized by UV-VIS spectroscopy, dynamic light scattering (DLS), and zeta potential. Four groups of eight animals each were formed and labelled A, B, C, and D, which received intra-articular injections of AuNPs, curcumin, AuNP-curcumin, and physiologic solution, respectively. After seven weeks, the cartilage of the stifle joint (SJ) was rated on a scale ranging from 0 to 24. Combination of AuNP-curcumin demonstrated good stability and therapeutic applications, but it did not differ significantly (P>0.05) from groups A and B. However, the control group had a significantly lower score (P<0.001). Results of this study demonstrated the importance of developing new nanodrugs. In this case, the combination of AuNPs and curcumin yielded the nanodrug effects suggestive of a potential for application in the treatment of OA.