Outcome of tenoscopically guided palmar/plantar annular ligament desmotomy for the treatment of palmar/plantar annular ligament constriction without concurrent intrathecal soft-tissue injury in a UK horse population.

OBJECTIVE: To determine the outcome of tenoscopically guided palmar/plantar annular ligament (PAL) desmotomy to treat PAL constriction without concurrent intrathecal soft-tissue injury, notably of the digital flexor tendons and manica flexoria. STUDY DESIGN: Retrospective multicenter cohort study. ANIMALS: Sixty-five horses. METHODS: Horses from four UK equine hospitals, with digital flexor tendon sheath (DFTS) tenosynovitis, which underwent tenoscopically guided PAL desmotomy for treatment of PAL constriction between 2017 and 2022 were included. All horses had lameness isolated to the DFTS/PAL, and PAL constriction was diagnosed tenoscopically when there was difficulty maneuvering the endoscope into or through the fetlock canal. Horses with tearing of the digital flexor tendons and/or manica flexoria, or any other intrathecal pathology, were excluded. Follow up was via structured telephone questionnaire. RESULTS: Follow up (median 25 months) was available for 61 horses with cobs and ponies predominating. Forty-two returned to their previous level of work, or a higher level, postoperatively and 50 owners were satisfied with the outcome of surgery. Eleven horses returned to lower level exercise, and six were retired/euthanized as they did not regain soundness. Fifty-two horses achieved soundness (median 3 months postoperatively). CONCLUSION: Tenoscopically guided PAL desmotomy for the treatment of PAL constriction in the absence of intrathecal soft tissue injury had a good prognosis for return to previous levels of exercise in a UK horse population. CLINICAL SIGNIFICANCE: The prognosis for horses undergoing tenoscopically guided PAL desmotomy to treat PAL constriction in the absence of intrathecal injury is better than previously described. Cobs and ponies seem to be predisposed to PAL constriction in agreement with the previous literature.

Successful total hip arthroplasty in a miniature horse.

OBJECTIVE: To describe the surgical treatment, postoperative management, and outcome of a miniature horse undergoing total hip arthroplasty (THA). STUDY DESIGN: Case report. ANIMALS: A 4-year-old miniature horse stallion weighing 85 kg. METHODS: The horse presented with left coxofemoral luxation of ~6 weeks duration. Computed tomography confirmed craniodorsal luxation with marked degenerative changes to the femoral head. The horse underwent THA using cementless press fit implants, including an interlocking lateral bolt for the femoral stem. RESULTS: The horse recovered well from anesthesia but suffered a coma-like episode after returning to a stable. Following treatment of presumed hypovolemia, the horse regained normal mentation and was discharged 24 days after surgery. At reassessment 12 weeks postoperatively, the horse was 2/10 left hind limb lameness at trot with good healing of the surgery site. Five months postoperatively mild (1/10) lameness remained at trot but the horse was able to canter normally on both reins. The horse has since been managed normally with no veterinary treatment required for 32 months postoperatively. CONCLUSION: Total hip arthroplasty is possible in miniature horses weighing up to 85 kg and can result in a good long-term outcome.

The 2023 ACR/EULAR Classification Criteria for Calcium Pyrophosphate Deposition Disease.

OBJECTIVE: Calcium pyrophosphate deposition (CPPD) disease is prevalent and has diverse presentations, but there are no validated classification criteria for this symptomatic arthritis. The American College of Rheumatology (ACR) and EULAR have developed the first-ever validated classification criteria for symptomatic CPPD disease. METHODS: Supported by the ACR and EULAR, a multinational group of investigators followed established methodology to develop these disease classification criteria. The group generated lists of candidate items and refined their definitions, collected de-identified patient profiles, evaluated strengths of associations between candidate items and CPPD disease, developed a classification criteria framework, and used multi-criterion decision analysis to define criteria weights and a classification threshold score. The criteria were validated in an independent cohort. RESULTS: Among patients with joint pain, swelling, or tenderness (entry criterion) whose symptoms are not fully explained by an alternative disease (exclusion criterion), the presence of crowned dens syndrome or calcium pyrophosphate crystals in synovial fluid are sufficient to classify a patient as having CPPD disease. In the absence of these findings, a score >56 points using weighted criteria, comprising clinical features, associated metabolic disorders, and results of laboratory and imaging investigations, can be used to classify as CPPD disease. These criteria had a sensitivity of 92.2% and specificity of 87.9% in the derivation cohort (190 CPPD cases, 148 mimickers), whereas sensitivity was 99.2% and specificity was 92.5% in the validation cohort (251 CPPD cases, 162 mimickers). CONCLUSION: The 2023 ACR/EULAR CPPD disease classification criteria have excellent performance characteristics and will facilitate research in this field.

The 2023 ACR/EULAR classification criteria for calcium pyrophosphate deposition disease.

OBJECTIVE: Calcium pyrophosphate deposition (CPPD) disease is prevalent and has diverse presentations, but there are no validated classification criteria for this symptomatic arthritis. The American College of Rheumatology (ACR) and EULAR have developed the first-ever validated classification criteria for symptomatic CPPD disease. METHODS: Supported by the ACR and EULAR, a multinational group of investigators followed established methodology to develop these disease classification criteria. The group generated lists of candidate items and refined their definitions, collected de-identified patient profiles, evaluated strengths of associations between candidate items and CPPD disease, developed a classification criteria framework, and used multi-criterion decision analysis to define criteria weights and a classification threshold score. The criteria were validated in an independent cohort. RESULTS: Among patients with joint pain, swelling, or tenderness (entry criterion) whose symptoms are not fully explained by an alternative disease (exclusion criterion), the presence of crowned dens syndrome or calcium pyrophosphate crystals in synovial fluid are sufficient to classify a patient as having CPPD disease. In the absence of these findings, a score>56 points using weighted criteria, comprising clinical features, associated metabolic disorders, and results of laboratory and imaging investigations, can be used to classify as CPPD disease. These criteria had a sensitivity of 92.2% and specificity of 87.9% in the derivation cohort (190 CPPD cases, 148 mimickers), whereas sensitivity was 99.2% and specificity was 92.5% in the validation cohort (251 CPPD cases, 162 mimickers). CONCLUSION: The 2023 ACR/EULAR CPPD disease classification criteria have excellent performance characteristics and will facilitate research in this field.

An Update on the Diagnosis and Management of Calcium Crystal Disease.

PURPOSE OF REVIEW: This article aims to review the challenges to diagnosis and management of calcium crystal deposition diseases and evaluate the literature published over the past 3 years. RECENT FINDINGS: The awaited development of classification criteria is an essential step in the progression of calcium crystal deposition disease clinical research. There have been recent improvements in the accuracy of imaging for the diagnosis of crystal deposition diseases with published definitions of characteristic features. Factors associated with acute flares of disease have been identified and an association with increased cardiovascular risk has been demonstrated. Targeted treatment options for calcium crystal diseases remain elusive. However, there have been advances in understanding the molecular mechanisms of disease revealing potential targets for future drug development. Calcium-crystal deposition diseases are increasing in incidence and prevalence as populations age and continue to associate with a high burden of disability. Despite this, calcium crystal deposition disease remains under-studied with a paucity of evidence-based treatment guidelines.

Multidisciplinary approach to anti-MDA5 antibody-positive dermatomyositis associated with rapidly progressive interstitial lung disease.

A man in his 40s was referred to our centre with rapidly progressive interstitial lung disease for lung transplant evaluation. Three months prior to his presentation he had developed periorbital oedema and discolouration, papules over the dorsal aspect of his metacarpophalangeal (MCP) joints and mucocutaneous ulcerations over the dorsum and palmar aspects of his MCPs. He had also been experiencing progressive shortness of breath. Based on the characteristic appearance of the cutaneous lesions, lack of muscle weakness on clinical examination, rapid progression of the interstitial lung disease together with presence of melanoma differentiation-associated gene 5 (MDA5) antibodies a diagnosis of anti-MDA5 dermatomyositis was made. Prompt treatment was initiated with aggressive combined immunomodulatory therapy that resulted in significant improvement in symptoms.

Forecasting and modeling of the COVID-19 pandemic in the USA with a timed intervention model.

We propose a novel Timed Intervention S, P, E, I, Q, R, D model for projecting the possible futures of the COVID-19 pandemic in the USA. The proposed model introduces a series of timed interventions that can account for the influence of real time changes in government policy and social norms. We consider three separate types of interventions: (i) Protective interventions: Where population moves from susceptible to protected corresponding to mask mandates, stay-at-home orders and/or social distancing. (ii) Release interventions: Where population moves from protected to susceptible corresponding to social distancing mandates and practices being lifted by policy or pandemic fatigue. (iii) Vaccination interventions: Where population moves from susceptible, protected, and exposed to recovered (meaning immune) corresponding to the mass immunization of the U.S. Population. By treating the pandemic with timed interventions, we are able to model the pandemic extremely effectively, as well as directly predicting the course of the pandemic under differing sets of intervention schedules. We show that without prompt effective protective/vaccination interventions the pandemic will be extended significantly and result in many millions of deaths in the U.S.

Non-severe COVID-19 is associated with endothelial damage and hypercoagulability despite pharmacological thromboprophylaxis.

BACKGROUND: Hypercoagulability and endothelial dysfunction are hallmarks of coronavirus disease 2019 (COVID-19) and appear to predict disease severity. A high incidence of thrombosis despite thromboprophylaxis is reported in patients with moderate to severe COVID-19. Recent randomized clinical trials suggest that therapeutic-intensity heparin confers a survival benefit in moderate-severity COVID-19 compared to standard-intensity heparin, potentially by harnessing heparin-mediated endothelial-stabilizing and anti-inflammatory effects. OBJECTIVE: We hypothesized that patients with moderate-severity COVID-19 exhibit enhanced hypercoagulability despite standard-intensity thromboprophylaxis with low molecular weight heparin (LMWH) compared to non-COVID-19 hospitalized patients. METHODS: Patients with moderate COVID-19 and a control group (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]-negative hospitalized patients) receiving LMWH thromboprophylaxis were recruited. Markers of endothelial damage and plasma thrombin generation parameters were assessed. RESULTS: Tissue plasminogen activator levels were significantly increased in the COVID-19 group (8.3 ± 4.4 vs. 4.9 ± 2.4 ng/ml; P = .02) compared to non-COVID-19-hospitalized patients. Despite thromboprophylaxis, mean endogenous thrombin potential was significantly increased among COVID-19 patients (1929 ± 448 vs. 1528 ± 460.8 nM*min; P = .04) but lag time to thrombin generation was significantly prolonged (8.1 ± 1.8 vs. 6.2 ± 1.8 mins; P = .02). While tissue factor pathway inhibitor (TFPI) levels were similar in both groups, in the presence of an inhibitory anti-TFPI antibody, the difference in lag time between the groups was abrogated. CONCLUSIONS: Collectively, these data demonstrate that COVID-19 of moderate severity is associated with increased plasma thrombin generation and endothelial damage, and that hypercoagulability persists despite standard LMWH thromboprophylaxis. These findings may be of clinical interest given recent clinical trial data which suggest escalated heparin dosing in non-severe COVID-19 may be associated with improved clinical outcomes.

Dynamic platelet function: A novel biomarker in inflammatory arthritis?

BACKGROUND: Patients with inflammatory arthritis die prematurely of cardiovascular disease. Inflammation activates platelets. Since treatment of inflammatory arthritis is associated with reduced mortality, and decreased platelet reactivity reduces cardiovascular events, we hypothesised that platelet reactivity as measured by dynamic platelet function (DPF) would be increased in patients with inflammatory arthritis and that reactivity could be reduced with therapeutic intervention. OBJECTIVES: To characterise platelet function using a validated physiological assay in patients with inflammatory arthritis before and after disease improvement. METHODS: 22 patients were recruited and treated as per local protocol. DPF was measured at baseline and after clinical improvement. Video microscopy was utilised to measure dynamic platelet behaviour in microliters of blood perfused over von Willebrand factor (VWF) at arterial shear rates (1500 s-1). Motion-analysis software measured the number of platelets interacting with VWF, translocating across VWF, the speed and distance platelets travelled across VWF, and stably adhering to the surface. Platelet parameters at baseline and following improvement were compared using Wilcoxon signed rank test and paired student t-test. Changes in platelet function were correlated to inflammatory disease markers by Pearson Correlation. RESULTS: 18 patients completed the study. Platelet adhesion decreased and platelet motion increased following treatment. Tender joint count correlated with platelet adhesion (Pearson r = 0.616, p≤0.01) while CRP correlated with velocity of platelet movement (Pearson r = 0.563, p≤0.01). CONCLUSIONS: Improvement in clinical markers of inflammation is associated with a corresponding change in platelet function. Given the association between reduced mortality and decreased platelet reactivity our results suggest that an appropriate assay of platelet function could guide future therapy of patients with inflammatory arthritis.

Haemophagocytic lymphohistiocytosis (HLH)-associated stress cardiomyopathy secondary to autoimmune conditions successfully treated with anakinra.

We describe two young cases of reactive haemophagocytic lymphohistiocytosis (HLH) with the resultant stress cardiomyopathy in the setting of underlying autoimmune diseases, systemic lupus erythematosus (SLE) and Still's disease. The initial presentation was similar in both cases with fever, hyperinflammatory response, hypotension (vasoplegia), bicytopenia and hyperferritinemia. Despite standard of care and multiple broad-spectrum antibiotics, both cases remained pyrexic and were ultimately admitted to the intensive therapy unit to treat cardiogenic shock. Echocardiogram of both cases showed low ejection fraction, the cause for which was not found until the final diagnosis of HLH was made. Both cases made a complete clinical and cardiac recovery following the initiation of high-dose glucocorticoids and anakinra.

Calcium pyrophosphate deposition (CPPD) disease - Treatment options.

In contrast to gout, no disease-modifying therapies currently exist that reduce articular crystal deposition of calcium pyrophosphate crystals (CPPs). Treatment is aimed at ameliorating the inflammatory response and reducing the frequency and severity of clinical symptoms due to CPP deposition (CPPD). Despite being one of the most common forms of inflammatory arthritis, CPPD remains under-studied and evidence-based treatment guidelines remain lacking. Commonly used treatments for clinical manifestations of CPPD (non-steroidal anti-inflammatory drugs [NSAIDs], colchicine and corticosteroids [CSs]) are extrapolated from use in gout. Anakinra and tocilizumab can be used in refractory cases. Though no current crystal-targeted treatments exist, studies suggest that nucleoside analogues and phosphocitrate can attenuate calcification of human cartilage ex-vivo. Hindering research, is the lack of a well-defined description of CPPD. However, international working groups have convened to establish classification criteria and validated outcome domains for CPPD. This should help facilitate the setting up of large multicentre studies, with well-defined cohorts, which can evaluate suitable therapies, providing high levels of evidence to guide clinicians. Here, we summarise and discuss the currently available anti-inflammatory treatment options for CPPD and discuss potential future crystal-targeted approaches.

CT more accurately detects foreign bodies within the equine foot than MRI or digital radiography.

Identification and characterization of foreign bodies in the distal limb of horses poses a diagnostic challenge. The aims of this prospective experimental cadaver study were to describe the appearance of five foreign body materials within the equine hoof using CT, MRI, and digital radiography (DR) and to compare interrater agreement among three reviewers. Fifty foreign bodies consisting of five materials were implanted at a solar location or a coronary location in 25 equine cadaver feet. The images were reviewed by three equine veterinarians experienced in advanced imaging interpretation, who were blinded to the material of the foreign body. Foreign bodies were graded on visibility and appearance. Sensitivity and specificity were calculated for accurate identification of the different materials. Interrater agreement was assessed using Fleiss' kappa. Computed tomography had higher visibility score, sensitivity/specificity, and interrater agreement for detection of all materials; particularly slate, glass, and dry wood, compared to the other imaging modalities. Soaked wood and plastic had lower sensitivity (31-33%) on CT with a similar attenuation of the two materials. Foreign bodies were often visible on MRI, although with similar appearance and unclear details. On DR, only slate and glass were visible. The interrater agreement for identifying the correct material was almost perfect for slate, glass, and dry wood (κ = 0.92-1.00) and poor for plastic and soaked wood (κ < 0.20) on CT. Interrater agreement was poor for all materials on MRI and DR (κ < 0.20), with the except for fair (κ = 0.28) for slate on DR and moderate (κ = 0.28) for soaked wood on MRI.

Assessment of intrasynovial injection in horses by contrast-enhanced ultrasonography using air bubbles created by agitation of solution.

BACKGROUND: Accuracy of intrasynovial injections can be challenging to assess in a clinical setting in horses. Contrast-enhanced ultrasonography (CEUS) using injectate agitated with air has been used to determine the success rates of synovial injections in human rheumatology. OBJECTIVES: To assess the diagnostic sensitivity and specificity of CEUS and to describe its clinical use. STUDY DESIGNS: Cadaveric study followed by a prospective descriptive observational study. METHODS: Part 1: CEUS was performed following injection of agitated methylene-blue solution targeting 13 different anatomical synovial structures from three equine cadavers. Contrast was seen as hyperechoic dots, patches or lines on ultrasonography. CEUS was classified as positive if contrast was considered to be intrasynovial and negative if contrast was considered to be extrasynovial. A second synoviocentesis was performed to determine if the injection was intrasynovial based on the presence or absence of methylene-blue. Estimates of sensitivity and specificity were calculated. Part 2: CEUS was performed following injection of agitated solutions targeting synovial structures as part of routine investigation and treatment of clinical cases. RESULTS: Part 1: CEUS was correctly classified as positive or negative in all intrasynovial and extrasynovial injections respectively. The sensitivity estimate was 100% (CI 93%-100%) and the specificity estimates was 100% (CI 16%-100%). Part 2: The technique was used safely for 26 injections (14 horses; 19 different synovial structures) administered to localise or treat lameness. Traumatic intersynovial communications or synovial membrane defects were identified using CEUS in 3 horses. MAIN LIMITATIONS: The low number of extrasynovial injections in Part 1 resulted in an imprecise specificity estimate. CONCLUSIONS: In horses, CEUS performed following intended intrasynovial injection can be useful for identifying unsuccessful injections.

The COVIRL002 Trial-Tocilizumab for management of severe, non-critical COVID-19 infection: A structured summary of a study protocol for a randomised controlled trial.

OBJECTIVES: Tocilizumab is a humanized monoclonal antibody which targets and inhibits interleukin-6 (IL-6) and has demonstrated efficacy in treating diseases associated with hyper-inflammation. Data are suggestive of tocilizumab as a potential treatment for patients with COVID-19 infection. The aim of this study is to determine the safety and efficacy of standard dose versus low dose tocilizumab in adults with severe, non-critical, PCR-confirmed COVID-19 infection with evidence of progressive decline in respiratory function and evolving systemic inflammation on time to intubation, non-invasive ventilation and/or all-cause mortality. TRIAL DESIGN: This trial is a phase 2, open label, two-stage, multicentre, randomised trial. PARTICIPANTS: Adult subjects with severe, non-critical, PCR-confirmed COVID-19 infection with evidence of progressive decline in respiratory function and evolving systemic inflammation requiring admission to hospital at St. Vincent's University Hospital and Mater Misericordiae University Hospital, Dublin, Ireland. Inclusion criteria Aged 18 years or older. Confirmed SARS-CoV2 infection (as defined by positive PCR). Evidence of hyper inflammatory state as evidenced by at least three of the following: Documented temperature >38°C in the past 48 hours, IL6 >40 pg/ml, or in its absence D-dimer >1.5 µgFEU /ml, Elevated CRP (>100mg/L) and/or a three-fold increase since presentation, Elevated ferritin X5 ULN, Elevated LDH (above the ULN), Elevated fibrinogen (above the ULN). Pulmonary infiltrates on chest imaging. Moderate to severe respiratory failure as defined by PaO2/FiO2≤300mmHg. INTERVENTION AND COMPARATOR: Intervention for participants in this trial is SOC plus Tocilizumab compared to SOC alone (comparator). For Stage 1, following randomisation, subjects will receive either (Arm 1) SOC alone or (Arm 2) SOC plus Tocilizumab (standard single dose - 8mg/kg, infused over 60 minutes. Once stage 1 has fully recruited, subsequent participants will be enrolled directly into Stage 2 and receive either (Arm 1) SOC plus Tocilizumab (standard single dose - 8mg/kg, infused over 60 minutes or (Arm 2) SOC plus Tocilizumab (standard single dose - 4mg/kg, infused over 60 minutes). MAIN OUTCOMES: The primary endpoint for this study is the time to a composite primary endpoint of progression to intubation and ventilation, non-invasive ventilation or death within 28 days post randomisation. RANDOMISATION: Eligible patients will be randomised (1:1) using a central register. Randomisation will be performed through an interactive, web-based electronic data capturing database. In stage 1, eligible participants will be randomised (1:1) to (Arm 1) SOC alone or to (Arm 2) SOC with single dose (8mg/kg, maximum 800mg) intravenous tocilizumab infused over 60 minutes. In stage 2, eligible participants will be randomised (1:1) to receive either (Arm 1) single, standard dose (8mg/kg, maximum 800mg) intravenous tocilizumab infused over 60 minutes or (Arm 2) reduced dose (4mg/kg, maximum 800mg) intravenous tocilizumab infused over 60 minutes. BLINDING: This study is open label. The study will not be blinded to investigators, subjects, or medical or nursing staff. The trial statistician will be blinded for data analysis and will be kept unaware of treatment group assignments. To facilitate this, the randomisation schedule will be drawn up by an independent statistician and objective criteria were defined for the primary outcome to minimize potential bias. NUMBERS TO BE RANDOMISED: In stage 1, 90 subjects will be randomised 1:1, 45 to SOC and 45 subjects to SOC plus Tocilizumab (8mg/kg, infused over 60 minutes). In stage 2, sample size calculation for the dose evaluation stage will use data generated from stage 1 using the same primary endpoint as in stage 1. TRIAL STATUS: The COVIRL002 trial (Protocol version 1.4, 13th May 2020) commenced in May 2020 at St. Vincent's University Hospital and Mater Misericordiae University Hospital, Dublin, Ireland. Recruitment is proceeding with the aim to achieve the target sample size on or before April 2021. TRIAL REGISTRATION: COVIRL002 was registered 25 June 2020 under EudraCT number: 2020-001767-86 and Protocol identification: UCDCRC/20/02. FULL PROTOCOL: The full protocol for COVIRL002 is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines (Additional file 2).

Comparison of Serum Amyloid A Measurements in Equine Synovial Fluid With Routine Diagnostic Methods to Detect Synovial Infection in a Clinical Environment.

Synovial fluid analysis is utilized to diagnose septic synovitis. However, not all cases are clearly and rapidly discernible with the diagnostic tools available in the laboratory. Serum amyloid A (SAA), an acute phase protein, has been shown to be elevated in synovial fluid from inflamed synovial structures. The goal of this study is to describe the correlation between two diagnostic tests measuring equine SAA levels in septic and non-septic synovial structures and to understand the correlation between an elevated SAA result and synovial sepsis. Prospective estimation of sensitivity (Se) and specificity (Sp) of two tests, handheld and ELISA, measuring SAA in synovial fluid was completed in 62 horses presented with injured synovial structures. The comparison was made to a reference diagnosis based on white cell count, percentage of neutrophils, intracellular bacteria and bacterial culture on synovial fluid. Handheld test levels were classified as: 4 lines visible-SAA level negative; 3 lines visible-SAA level mild; 2 lines visible-SAA level moderate; and 1 line visible-SAA level severe and compared to the numerical value obtained with ELISA test. The ELISA SAA test had an area under the curve of 0.88 (0.78-0.98). An ELISA cut-off of 23.95 µg/mL maximized Se and Sp. This cutoff gave a Se of 0.93 (0.66-1.00) and Sp of 0.77 (0.63-0.88). The handheld test was highly correlated with the ELISA SAA test (Spearman rank correlation 0.96) and at a cutoff of moderate or higher for positive results gave identical Se and Sp. Se and Sp of synovial fluid SAA are very reliable when clinical signs of synovitis are present for >6 h. This test, in conjunction with traditional methods, can assist practitioners to rapidly diagnose and expedite appropriate intervention of synovial sepsis.

Investigation of the efficacy of the GnRH agonist deslorelin in mitigating intraspecific aggression in captive male Amur leopards (Panthera pardus orientalis).

Housing bachelor groups is a necessary aspect of the care and husbandry of non-breeding individuals in zoological collections. Intraspecific aggressive behaviors may occur in this setting despite management strategies designed to mitigate these behaviors. Androgens (including testosterone) are associated with aggression in male species and interventional techniques to alter the animals' physiology to modify aggressive behavior are sometimes required. When agonistic behavior and physical aggression in two mature male Amur leopards housed together at Tayto Park escalated, despite all strategic management involvements, further intervention to moderate aggression was required. The gonadotropin-releasing hormone (GnRH) agonist, deslorelin, has been found to be effective in reducing androgens in domestic and non-domestic carnivores. We hypothesized that deslorelin's suppressive effect on hypothalamic-pituitary-gonadal axis would mitigate intraspecific aggression in two male intact leopards. Behavioral observations were carried out pre- and post-implant implantation of 9.4 mg deslorelin implant. The frequency of agonistic/aggressive behaviors for both leopards declined significantly (p < 0.05), as did marking behaviors post-implantation (p < 0.001). The insertion of deslorelin implants in two male intact leopards demonstrating increased frequency and severity of aggressive behaviors resulted in a reduction of the frequency of these behaviors. Deslorelin implantation should be considered for management of interspecific aggression of intact male leopards in bachelor groups.

Soluble glycoprotein VI, a specific marker of platelet activation is increased in the plasma of subjects with seropositive rheumatoid arthritis.

OBJECTIVES: Anti-citrullinated protein antibodies (ACPA) have been shown to cause platelet activation in vitro, through the low-affinity immunoglobulin G (IgG) receptor (FcγRIIa) on platelets. Platelet activation via engagement of FcγRIIa results in proteolytic cleavage and shedding of platelet specific glycoprotein VI (GPVI) which can be detected in the plasma as soluble GPVI (sGPVI). We hypothesized that plasma levels of sGPVI would be increased among patients with seropositive RA as a consequence of antibody-induced platelet activation and GPVI shedding. METHODS: Samples from 84 patients with RA (65 seropositive and 19 seronegative) and 67 healthy controls were collected prospectively and analysed for sGPVI using a standardised ELISA. RESULTS: Patients with seropositive RA had significantly higher levels of sGPVI compared to seronegative RA and controls. Median (IQR) sGPVI levels were 4.2 ng/ml (3.2, 8.0) in seropositve RA, 2.2 ng/ml (1.5, 3.5) in seronegative RA and 2.2 ng/ml (1.6, 3.4) in controls (p<0.0001). sGPVI levels correlated with ACPA titres (r = 0.32, p = 0.0026) and with RF titres (r = 0.48, p<0.0001). CONCLUSION: Plasma sGPVI, a specific marker of platelet activation is increased among patients with seropositive RA.