Cyclooxygenases 1 and 2 inhibition and analgesic efficacy of dipyrone at different doses or meloxicam in cats after ovariohysterectomy

ObjectiveTo evaluate the cyclooxygenases (COX) inhibition, adverse effects and analgesic efficacy of dipyrone or meloxicam in cats undergoing elective ovariohysterectomy.Study designProspective, blinded, randomized, clinical study.AnimalsA total of 30 healthy young cats.MethodsThe cats were randomly assigned to three postoperative groups: D25 (dipyrone 25 mg kg^?1 every 24 hours), D12.5 (dipyrone 12.5 mg kg^?1 every 12 hours) and M (meloxicam 0.1 mg kg^?1 every 24 hours). In the first 24 hours, the drugs were administered intravenously (IV), and then orally for 6 (dipyrone) or 3 days (meloxicam). Prostanoids thromboxane B₂ and prostaglandin E₂ concentrations served as indicators of COX activity and, with physiological variables and pain and sedation scores, were measured for 24 hours after first analgesic administration. Rescue analgesia (tramadol, 2 mg kg^?1 IV) was provided if Glasgow feline composite measure pain scale (CMPS-Feline) ≥5. Laboratory tests included symmetric dimethylarginine and adverse effects were evaluated regularly up to 7 and 10 days after surgery, respectively. Parametric and nonparametric data were analyzed with two-way anova and Kruskal-Wallis tests, respectively (p < 0.05).ResultsIn the first half hour after analgesic administration, COX-1 activity was close to zero and remained significantly lower than before drug administration for 24 hours in all groups. The inhibition of COX-2 activity was significant for 30 minutes in all groups and up to 4 hours in group M. No alterations in laboratory tests or significant adverse effects were observed. Pain scores and need for rescue analgesia did not differ statistically among groups.ConclusionsDipyrone at both doses and meloxicam provided a nonselective inhibition of COX-1 and -2 activities and effective analgesia without causing significant adverse effects or laboratory tests alterations.Clinical relevanceDipyrone at both doses provides equally effective analgesia without causing adverse effects in cats undergoing ovariohysterectomy.     

In vivo effects of meloxicam on inflammatory mediators,MMP activity and cartilage biomarkers in equine joints with acute synovitis

Reasons for performing study: Meloxicam is a commonly used nonsteroidal anti‐inflammatory drug in equine practice, but little is known about its in vivo effects on joint inflammation and cartilage turnover. Objectives: To study the effects of meloxicam on biomarkers of inflammation, matrix metalloproteinase (MMP) activity, and cartilage biomarkers in joints with experimental synovitis. Methods: In a 2‐period cross‐over study, synovitis was induced at T = 0 h in the L or R intercarpal joint of 6 horses by intraarticular injection of 0.5 ng lipopolysaccharide (LPS). Horses received once daily meloxicam (0.6 mg/kg bwt per os) or placebo starting at post injection hour (PIH) 2, and clinical evaluations as well as blood and synovial fluid (SF) sampling were performed at PIH 0, 8, 24 and 168. Synovial fluid was analysed for prostaglandin E₂, bradykinin, substance P, general MMP activity, glycosaminoglycans (GAG), CS846 epitope, type II collagen cleavage fragments (C2C) and type II collagen carboxypropeptide (CPII). Concentrations in meloxicam‐ vs. placebo‐treated joints over time were compared using a linear mixed model. Results: Lipopolysaccharide injection caused marked transient synovitis without systemic effects. Meloxicam caused a significant reduction in lameness at PIH 8 and 24 and tended to reduce effusion. In addition, meloxicam significantly suppressed SF prostaglandin E₂ and substance P release at PIH 8 and bradykinin at PIH 24 compared to placebo treatment. General MMP activity at PIH 8 and 24 was significantly lower in meloxicam‐ vs. placebo‐treated joints, as were GAG, C2C and CPII concentrations at PIH 24. Conclusions: Acute transient synovitis leads to substantial increases in SF biomarkers of inflammation, MMP activity and cartilage turnover, which can be significantly suppressed by meloxicam. Potential relevance: Early oral treatment with meloxicam ameliorates not only clinical signs and joint inflammation in acute synovitis, but may also limit inflammation‐induced cartilage catabolism.     

Rethinking equine gastric ulcer syndrome: Part 1 – Terminology,clinical signs and diagnosis

Equine gastric ulcer syndrome (EGUS) is a common condition in the horse. A series of recent articles highlighting differences in healing of squamous and glandular ulceration have reinvigorated interest in the condition. The purpose of this series of articles is to review the current thinking on EGUS with particular emphasis on the differences between diseases of the squamous and glandular mucosae. This article, the first will review the terminology, clinical signs and diagnosis of EGUS in the horse.     

Identification of equine herpesvirus 3 (equine coital exanthema virus), equine gammaherpesviruses 2 and 5, equine adenoviruses 1 and 2, equine arteritis virus and equine rhinitis A virus by polymerase chain reaction

OBJECTIVE: To develop rapid (< 8 hour) tests using polymerase chain reaction (PCR) for the diagnosis of equine herpesvirus 3 (EHV3; equine coital exanthema virus), equine gammaherpesviruses 2 (EHV2) and EHV5, equine adenovirus 1 (EAdV1), EAdV2, equine arteritis virus (EAV), equine rhinitis A virus (ERAV; formerly equine rhinovirus 1) DESIGN: Either single round or second round (seminested) PCRs were developed and validated. METHODS: Oligonucleotide primers were designed that were specific for each virus, PCR conditions were defined and the specificity and sensitivity of the assays were determined. The application of the tests was validated using a number of independent virus isolates for most of the viruses studied. The PCRs were applied directly to clinical samples where samples were available. RESULTS: We developed a single round PCR for the diagnosis of EHV3, a seminested PCR for EHV2 and single round PCRs for EHV5, EAdV1, EAdV2 and RT-PCRs for EAV and ERAV. The PCR primer sets for each virus were designed and shown to be highly specific (did not amplify any recognised non-target template) and sensitive (detection of minimal amounts of virus) and, where multiple virus isolates were available all isolates were detected. CONCLUSION: The development and validation of a comprehensive panel of PCR diagnostic tests, predominantly for viruses causing equine respiratory disease, that can be completed within 8 hours from receipt of clinical samples, provides a major advance in the rapid diagnosis or exclusion diagnosis of these endemic equine virus diseases in Australia.     

Incorporation of sunflower oil or linseed oil in equine compound feedstuff: 1 Effects on haematology and on fatty acids profiles in the red blood cells membranes

Eight trained horses (6 mares – 2 geldings, 6 Selle Français, 2 Trotteur Français, 12 ± 5.8 years old, 538 ± 72.5 kg) were offered three diets to potentially affect haematology and the fatty acids (FA) profiles in red blood cells (RBC) membranes. The control diet was composed of 50% hay and 50% concentrate containing mainly rolled barley (48%) and whole spelt (48%). In the case of sunflower oil diet, sunflower oil (62.0% of α‐linoleic acid, LA) was incorporated at a rate of 8% and substituted by an equal proportion of barley. In the linseed oil diet, first cold‐pressed linseed oil (56.0% of α‐linolenic acid, ALA) was utilised at a similar incorporation rate of 8%. The experimental design consisted of three 3 × 3 latin squares with one being incomplete. Each period lasted 8 weeks. On average, the total feed intake (straw excluded) was 6.2 kg/day and the oil intake 0.278 kg/day. The oils significantly increased the concentrations of RBC, haemoglobin and haematocrit. The oils had no significant impact on the haematology profiles except that platelets tended to decrease in both oil‐based diets. The most abundant FA in the RBC membranes of the control diet samples were in the decreasing order LA, C18:1n9‐7, C18:0, C16:0 and the arachidonic acid (ARA) respectively. The sunflower oil supplementation slightly increased the amount of LA (36.23 vs. 34.72 mg/dl, p = 0.55) and C22:4n‐6 (0.21 vs. 0.09 mg/dl, p = 0.22), while the decrease was observed in case of other FA (C16:1n‐7, 1.08 vs. 1.42 mg/dl, p = 0.03), C20:3n‐6 (0.22 vs. 0.31 mg/dl, p = 0.02), and ARA (1.17 vs. 1.63 mg/dl, p = 0.08). Linseed oil induced similar effects in the n‐6 series FA profiles. In the context of practical applications, our results show that linseed oil incorporation in the diet could improve the haematology and the n‐3 FA profiles potentially leading to an increased performance.     

Interferon-gamma, interleukin-4 and interleukin-10 production by T helper cells reveals intact Th1 and regulatory TR1 cell activation and a delay of the Th2 cell response in equine neonates and foals

Cytokines produced by T helper (Th) cells are important in orchestrating the immune response during health and disease. Recent reports indicated that cytokine mRNA expression in foals is often quantitatively lower than that of adult horses suggesting that foal T cells are not fully mature. Here, peripheral blood mononuclear cells from foals and adult horses were stimulated with phorbol 12-myristate 13-acetate and analyzed for intracellular interferon-gamma (IFN-γ), interleukin-4 (IL-4) and IL-10 production, representing the Th1, Th2 and regulatory T_R1 cell phenotypes respectively, by flow cytometry. In agreement with previous reports, all three cytokines were quantitatively reduced in foals compared to adults. However, the balance between Th1 and Th2 cytokines (IFN-γ/IL-4 ratio) showed a clear Th1-biased response in foals by 6 and 12 weeks of life, while similar IFN-γ/IL-10 ratios were found in foals and adult horses. By day 5 after birth, intracellular IFN-γ production by foal CD4⁺ and CD8⁺ T cells resembled that in adults. Overall, IL-4 production was low in foals. IL-4⁺ cells peaked at day 5 of age when IL-4 was mainly produced by IgE⁺ cells. Relative percentages of IL-4⁺ Th2 cells were significantly lower in foals at all time points. The data suggested that equine neonates and young foals have an impaired Th2 response, that the immune response of foals is Th1 biased, that IFN-γ production by Th and cytotoxic T cells is qualitatively similar to adult horses, and regulatory IL-10 production by T cells is developmentally mature in foals during the first three months of life.     

Hereditary equine regional dermal asthenia (HERDA) in Quarter Horses: A review of clinical signs,genetics and research

Hereditary equine regional dermal asthenia (HERDA) results from a genetic mutation which affects the skin and other tissues of Quarter Horses and horses with Quarter Horse lineage. The disease HERDA has an autosomal recessive mode of inheritance and has become a significant concern in the Quarter Horse industry due to the high frequency of heterozygote carriers. Affected homozygous horses appear normal at birth; however, within the first 2 years of life they usually acquire loose, hyperextensible skin and wounds which result in disfiguring scars either spontaneously or from minor trauma. Some severely affected horses also develop haematomas and seromas. Consequently, most affected horses are subjected to euthanasia at an early age. No treatment options other than palliative therapy currently exist. As part of a five panel test ( http://www.aqha.com/News/News-Articles/2013/April/04292013-Genetic-Testing.aspx ) the American Quarter Horse Association presently requires DNA testing for HERDA on all breeding stallions. There are currently no restrictions on registration of horses heterozygous or homozygous for the HERDA mutation. Due to the autosomal recessive nature of the disease, Quarter Horse mares and horses of all breeds from HERDA‐associated bloodlines should also be tested.     

Two‐ and three‐dimensional computed tomographic anatomy of the enamel,infundibulae and pulp of 126 equine cheek teeth. Part 2: Findings in teeth with macroscopic occlusal or computed tomographic lesions

Reasons for performing study: Dental disease often presents a diagnostic challenge in the horse. Computed tomography (CT) is increasingly used in the evaluation of head related disease in the horse, but the CT appearance of the most common dental diseases of horses has not yet been fully described. Objective: To describe the CT appearance of the peripheral enamel, pulp, infundibular enamel and cement in equine cheek teeth with macroscopic occlusal or CT lesions. Methods: In this study, 126 cadaveric cheek teeth with eruption ages of between 0.5 and 19 years were evaluated for lesions of their infundibulae, pulp and enamel using occlusal surface morphology, 2‐ (2D) and 3‐dimensional (3D) CT and anatomical sectioning. Variations in teeth with no macroscopic lesions have been described in a previous study. The infundibular lesions were categorised further into one of 6 classifications. Results: Infundibular lesions were identified on CT in 90% (115/128) of infundibulae. Of these, 65% (83/128) had infundibular lesions on occlusal surface examination. The extent of infundibular lesions observed varied with age group. All infundibulae over 6 years post eruption had detectable lesions. Peripheral enamel hypoplasia and enamel prolapses, were observed in 10% (12/126) and 1.6% (2/126) of teeth, respectively. The CT appearance of teeth with pulp infections was seen to vary with differing pathologies. Conclusions and potential relevance: The high prevalence of infundibular lesions should encourage consideration of their clinical significance, in addition to the role of infundibulae in dental disease of the horse. Two‐dimensional and 3D CT proved to be highly valuable imaging modalities for dental disease, enabling lesions within the enamel, infundibulae and pulp of equine cheek teeth to be easily detected. The results of this study will facilitate the use of 2D and 3D CT as clinical diagnostic tools for dental disease and aid in the selection of the most appropriate treatment protocol.     

In vitro and in vivo 2',5'-oligoadenylate synthetase activity induced by recombinant DNA-derived bovine interferon alpha I1 in bovine alveolar macrophages and blood mononuclear cells.

Biological responses to recombinant DNA-derived bovine interferon alpha (rBoIFN-alpha I1) by bovine alveolar macrophages were examined by measuring viral yield reduction and 2',5'-oligoadenylate synthetase (2',5'-OAS) production by IFN-treated cells. In vitro IFN pretreatment of alveolar macrophages reduced viral yield in cultures challenged exposed with parainfluenza-3 virus, compared with control cultures. In vitro treatment of alveolar macrophages with IFN also resulted in increased 2',5'-OAS activity. The 2',5'-OAS activity was measured in alveolar macrophages and blood mononuclear leukocytes of calves injected IM with 3.6 x 10(6) U of rBoIFN-alpha I1/kg of body weight. The IFN action was monitored by measuring 2',5'-OAS activity of blood mononuclear leukocytes beginning 6 days before and ending 24 hours after IFN treatment. The 2',5'-OAS activity in the blood mononuclear leukocytes sharply increased 24 hours after IFN treatment, indicating response to IFN. The alveolar macrophages collected from the same calves 24 hours after IFN administration also had increased 2',5'-OAS activity, compared with alveolar macrophages from the same calves collected 6 days before treatment. Increased 2',5'-OAS activity indicates: a possible mechanism of IFN action in cattle that may be responsible for viral yield reduction; potential use of high enzyme activity as a marker for IFN induction; and potential use of 2',5'-OAS activity as a marker for determining effects of IFN on bovine macrophages and other cells of the bovine immune system.     

青蒿琥酯通过Keap1/Nrf2通路抑制氧化应激改善犬急性肾损伤的体内外分析

本研究旨在观察青蒿琥酯对庆大霉素诱导犬急性肾损伤的抗氧化调节作用及其机制。将20只犬随机等分成4组：对照组(Control)、庆大霉素模型组(GM)、青蒿琥酯治疗组(GM+ART)、青蒿琥酯+ML385干预组(GM+ART+ML385)。除对照组,其他组犬采用注射GM建立AKI模型。成功造模后,GM+ART组给与青蒿琥酯,ART+ML385组给与ART和ML385,对照组和GM组给予生理盐水,试验期12 d。用不同浓度GM与MDCK细胞共培养,确定最佳浓度为4.0 mmol·L^-1,用相同方法确定ART最佳浓度为50.0 μmol·L^-1。将体外培养MDCK细胞、过表达Kelch样ECH相关蛋白1(Keap1)的MDCK细胞(M-K)和敲减核因子E2相关因子2(Nrf2)表达的MDCK细胞(M-SiNrf2)分别分成3组：健康对照组、GM对照组和GM+ART干预组,共培养24 h后用于检测。结果显示：1)在动物试验中,GM+ART组肌酐(Cr)、尿素氮(UN)及肾损伤因子1(KIM-1)水平显著低于GM组,GM+ART+ML385组Cr、UN及KIM-1水平显著高于GM+ART组。2)在动物试验中,与GM组比较,GM+ART组Nrf2和谷胱甘肽半胱氨酸连接酶催化亚基(GCLC)蛋白表达上调,Keap1蛋白表达下调,肾组织匀浆中总超氧化物歧化酶(T-SOD)和谷胱甘肽(GSH)水平升高,丙二醛(MDA)水平降低。与GM+ART组比较,给与ML385后Nrf2和GCLC蛋白表达下调,T-SOD和GSH水平降低。3)在细胞试验中,与4.0 mmol·L^-1 GM共培养的MDCK细胞比较,加入50.0 μmol·L^-1ART能显著提高细胞增殖率,降低ROS水平,下调Keap1表达,上调Nrf2、血红素氧合酶1(HO1)及GCLC表达。4)在细胞试验中,与MDCK细胞比较,在GM+ART相同处理下,M-K细胞和M-SiNrf2细胞Keap1蛋白表达上调,Nrf2、HO1及GCLC蛋白表达下调,细胞增殖率降低,ROS含量升高(P＜0.05或P＜0.01)。综上所述,青蒿琥酯对庆大霉素诱导犬急性肾损伤具有保护作用,其作用机制与青蒿琥酯通过Keap1/Nrf2信号通路抑制氧化应激反应有关。     

Immunohistochemical study of matrix metalloproteinases‐2 and ‐9, macrophage inflammatory protein‐2 and tissue inhibitors of matrix metalloproteinases‐1 and ‐2 in normal,purulonecrotic and fungal infected equine corneas

Objective Determine the effects of matrix metalloproteinases (MMPs)‐2, ‐9, macrophage inflammatory protein‐2 (MIP‐2), tissue inhibitors of matrix metalloproteinase (TIMP)‐1 and ‐2 by immunohistochemical expression in fungal affected and purulonecrotic corneas. Procedure Paraffin‐embedded equine corneal samples; normal (n = 9), fungal affected (FA; n = 26), and purulonecrotic without fungi (PN; n = 41) were evaluated immunohistochemically for MMP‐2, ‐9, MIP‐2, TIMP‐1 and ‐2. The number of immunoreactive inflammatory cells was counted and statistics analyzed. Western blot was performed to detect MMP‐2, MMP‐9, TIMP‐1 and TIMP‐2 proteins. Results Matrix metalloproteinases‐2, ‐9, MIP‐2, TIMP‐1 and ‐2 immunoreactivity was identified in corneal epithelium of normal corneas, and in corneal epithelium, inflammatory cells, keratocytes, and vascular endothelial cells of both FA and PN samples. Inflammatory cell immunoreactivity was significantly higher in FA and PN samples than in the normal corneas. There was positive correlation between MMP‐2 and MIP‐2, MMP‐9 and MIP‐2, and MMP‐9 and TIMP‐1 in inflammatory cell immunoreactivity in FA samples. There was positive correlation between MMP‐9 and MIP‐2, MMP‐9 and TIMP‐2, MIP‐2 and TIMP‐1, and MIP‐2 and TIMP‐2 in inflammatory cell immunoreactivity in PN samples. Western blot confirmed the presence of all four proteins in equine corneal samples. Conclusion Increased immunoreactivity of MMP‐2 and ‐9 in FA and PN samples is indirectly related to MIP‐2 through its role in neutrophil chemo‐attraction. Tissue inhibitors of matrix metalloproteinase‐1 and TIMP‐2 are up‐regulated in equine purulonecrotic and fungal keratitis secondary to MMP‐2 and MMP‐9 expression. The correlation between MMPs ‐2 and ‐9, MIP‐2, TIMPs ‐1 and ‐2 suggests that these proteins play a specific role in the pathogenesis of equine fungal keratitis.