Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 49
1.
Sci Rep ; 11(1): 11965, 2021 06 07.
Article En | MEDLINE | ID: mdl-34099810

Colchicine inhibits coronary and cerebrovascular events in patients with coronary artery disease (CAD), and although known to have anti-inflammatory properties, its mechanisms of action are incompletely understood. In this study, we investigated the effects of colchicine on platelet activation with a particular focus on its effects on activation via the collagen glycoprotein (GP)VI receptor, P2Y12 receptor, and procoagulant platelet formation. Therapeutic concentrations of colchicine in vitro (equivalent to plasma levels) significantly decreased platelet aggregation in whole blood and in platelet rich plasma in response to collagen (multiplate aggregometry) and reduced reactive oxygen species (ROS) generation (H2DCF-DA, flow cytometry) in response to GPVI stimulation with collagen related peptide-XL (CRP-XL, GPVI specific agonist). Other platelet activation pathways including P-selectin expression, GPIIb/IIIa conformational change and procoagulant platelet formation (GSAO+/CD62P+) (flow cytometry) were inhibited with higher concentrations of colchicine known to inhibit microtubule depolymerization. Pathway specific mechanisms of action of colchicine on platelets, including modulation of the GPVI receptor pathway at low concentrations, may contribute to its protective role in CAD.


Colchicine/chemistry , Coronary Artery Disease/drug therapy , Platelet Membrane Glycoproteins/metabolism , Reactive Oxygen Species/chemistry , Blood Platelets/drug effects , Carrier Proteins/metabolism , Colchicine/metabolism , Colchicine/pharmacology , Gene Expression Regulation/drug effects , Humans , P-Selectin/metabolism , Peptides/metabolism , Platelet Activation/drug effects , Platelet Aggregation/drug effects , Platelet Glycoprotein GPIIb-IIIa Complex/genetics , Platelet Glycoprotein GPIIb-IIIa Complex/metabolism , Receptors, Collagen/genetics , Receptors, Collagen/metabolism , Signal Transduction
2.
Heart Lung Circ ; 29(6): e69-e77, 2020 Jun.
Article En | MEDLINE | ID: mdl-32471696

The global coronavirus disease (COVID-19) pandemic poses an unprecedented stress on healthcare systems internationally. These Health system-wide demands call for efficient utilisation of resources at this time in a fair, consistent, ethical and efficient manner would improve our ability to treat patients. Excellent co-operation between hospital units (especially intensive care unit [ICU], emergency department [ED] and cardiology) is critical in ensuring optimal patient outcomes. The purpose of this document is to provide practical guidelines for the effective use of interventional cardiology services in Australia and New Zealand. The document will be updated regularly as new evidence and knowledge is gained with time. Goals Considerations.


Betacoronavirus , Consensus , Coronavirus Infections , Critical Care , Intensive Care Units , Pandemics , Pneumonia, Viral , Australia/epidemiology , COVID-19 , Cardiology/standards , Coronavirus Infections/epidemiology , Coronavirus Infections/physiopathology , Coronavirus Infections/therapy , Humans , New Zealand/epidemiology , Pneumonia, Viral/epidemiology , Pneumonia, Viral/physiopathology , Pneumonia, Viral/therapy , Practice Guidelines as Topic , SARS-CoV-2
4.
J Thromb Haemost ; 16(6): 1198-1210, 2018 06.
Article En | MEDLINE | ID: mdl-29569428

Essentials Procoagulant platelets can be detected using GSAO in human whole blood. Stable coronary artery disease is associated with a heightened procoagulant platelet response. Agonist-induced procoagulant platelet response is not inhibited by aspirin alone. Collagen plus thrombin induced procoagulant platelet response is partially resistant to clopidogrel. SUMMARY: Background Procoagulant platelets are a subset of highly activated platelets with a critical role in thrombin generation. Evaluation of their clinical utility in thrombotic disorders, such as coronary artery disease (CAD), has been thwarted by the lack of a sensitive and specific whole blood assay. Objectives We developed a novel assay, utilizing the cell death marker, GSAO [(4-(N-(S-glutathionylacetyl)amino)phenylarsonous acid], and the platelet activation marker, P-selectin, to identify procoagulant platelets in whole blood by flow cytometry. Patients/Methods Using this assay, we characterized the procoagulant platelet population in healthy controls and a cohort of patients undergoing elective coronary angiography. Results In patients with CAD, compared with patients without CAD, there was a heightened procoagulant platelet response to thrombin (25.2% vs. 12.2%), adenosine diphosphate (ADP) (7.8% vs. 2.7%) and thrombin plus collagen (27.2% vs. 18.3%). The heightened procoagulant platelet potential in CAD patients was not associated with other markers of platelet function, including aggregation, dense granule release and activation of α2b ß3 integrin. Although dual antiplatelet therapy (DAPT) was associated with partial suppression of procoagulant platelets, this inhibitory effect on a patient level could not be predicted by aggregation response to ADP and was not fully suppressed by clopidogrel. Conclusions We report for the first time that procoagulant platelets can be efficiently detected in a few microliters of whole blood using the cell death marker, GSAO, and the platelet activation marker, P-selectin. A heightened procoagulant platelet response may provide insight into the thrombotic risk of CAD and help identify a novel target for antiplatelet therapies in CAD.


Arsenicals/blood , Blood Coagulation , Blood Platelets/metabolism , Coronary Artery Disease/blood , Flow Cytometry , Glutathione/analogs & derivatives , P-Selectin/blood , Platelet Activation , Platelet Function Tests/methods , Aged , Aspirin/pharmacology , Biomarkers/blood , Blood Coagulation/drug effects , Blood Platelets/drug effects , Case-Control Studies , Clopidogrel/pharmacology , Coronary Angiography , Coronary Artery Disease/diagnostic imaging , Drug Resistance , Female , Glutathione/blood , Humans , Male , Middle Aged , Platelet Activation/drug effects , Platelet Aggregation Inhibitors/pharmacology , Predictive Value of Tests
6.
J Thromb Haemost ; 15(3): 477-486, 2017 03.
Article En | MEDLINE | ID: mdl-28058802

Essentials Cancer cachexia and cancer-associated thrombosis have not previously been mechanistically linked. We assessed thrombin generation and coagulation parameters in cachectic C26 tumor-bearing mice. C26 mice are hypercoagulable, partially corrected by blocking tumor derived interleukin-6. Coagulability and anti-inflammatory interventions may be clinically important in cancer cachexia. SUMMARY: Background Cancer cachexia and cancer-associated thrombosis are potentially fatal outcomes of advanced cancer, which have not previously been mechanistically linked. The colon 26 (C26) carcinoma is a well-established mouse model of complications of advanced cancer cachexia, partially dependent on high levels of interleukin-6 (IL-6) produced by the tumor. Objectives To assess if cancer cachexia altered the coagulation state and if this was attributable to tumor IL-6 production. Methods In male BALB/c*DBA2 (F1 hybrid) mice with a C26 tumor we used modified calibrated automated thrombogram and fibrin generation (based on overall hemostatic potential) assays to assess the functional coagulation state, and also examined fibrinogen, erythrocyte sedimentation rate (ESR), platelet count, tissue factor pathway inhibitor (TFPI) and hepatic expression of coagulation factors by microarray. C26 mice were compared with non-cachectic NC26, pair-fed and sham control mice. IL-6 expression in C26 cells was knocked down by lentiviral shRNA constructs. Results C26 mice with significant weight loss and highly elevated IL-6 had elevated thrombin generation, fibrinogen, ESR, platelets and TFPI compared with all control groups. Fibrin generation was elevated compared with pair-fed and sham controls but not compared with NC26 tumor mice. Hepatic expression of coagulation factors and fibrinolytic inhibitors was increased. Silencing IL-6 in the tumor significantly, but incompletely, attenuated the increased thrombin generation, fibrinogen and TFPI. Conclusions Cachectic C26 tumor-bearing mice are in a hypercoagulable state, which is partly attributable to IL-6 release by the tumor. The findings support the importance of the coagulation state in cancer cachexia and the clinical utility of anti-inflammatory interventions.


Blood Coagulation , Cachexia/metabolism , Interleukin-6/metabolism , Neoplasms/metabolism , Thrombin/metabolism , Animals , Cell Line, Tumor , Disease Models, Animal , Fibrin/metabolism , Fibrinogen/metabolism , Gene Expression Regulation, Neoplastic , Humans , Inflammation , Interleukin-6/genetics , Liver/metabolism , Male , Mice , Mice, Inbred BALB C , Mice, Inbred DBA , Neoplasm Transplantation , Tissue Array Analysis
7.
Int J Cardiol ; 199: 13-7, 2015 Nov 15.
Article En | MEDLINE | ID: mdl-26173168

BACKGROUND: Long-term studies following acute pulmonary embolism (PE) remain limited in the current era. A recent study from our collaborative group, in a contemporary adult population, showed substantially increased cardiovascular mortality following PE. We sought to evaluate the contribution of cardiovascular mortality to long-term outcomes in a different demographic that comprised of a significantly younger PE cohort. METHODS AND RESULTS: Demographic and clinical characteristics were retrospectively collected for this cohort, and similar methods and outcome measures were applied as detailed in the original study. We compared a population from a different metropolitan area (LH: Liverpool Hospital) to that from the original study (CRGH: Concord Hospital) over a similar time period. A total of 815 patients comprised this cohort with mean 5.3±3.8year follow-up. There were similar demographics between the two cohorts, though the mean age was significantly younger in LH group (60 vs 68years, p<0.001). Prior history of cardiovascular disease in the LH group was half of that present in the CRGH cohort. The overall mortality was 7.4% per patient-year. Patients with underlying cardiovascular disease when presenting with an acute PE had a 2.3-fold increased risk of death during follow-up compared to those without. Multivariate analysis showed that older age, male gender, malignancy, diabetes, cardiovascular disease and chronic pulmonary disease were independent predictors of post-discharge mortality. CONCLUSIONS: Despite our cohort being significantly younger with a lower incidence of pre-existing cardiovascular disease, cardiovascular disease was still a significant contributor to long-term outcomes and an important predictor of mortality following acute PE.


Cardiovascular Diseases/mortality , Pulmonary Embolism/mortality , Acute Disease , Age Factors , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Middle Aged , New South Wales/epidemiology , Retrospective Studies , Survival Rate/trends , Time Factors
8.
Int J Cardiol ; 184: 600-608, 2015 Apr 01.
Article En | MEDLINE | ID: mdl-25769007

UNLABELLED: Myotonic dystrophy (MD) is a multisystem, autosomal dominant disorder best known for its skeletal muscle manifestations. Cardiac manifestations arise as a result of myocardial fatty infiltration, degeneration and fibrosis and present most commonly as arrhythmias or conduction disturbances. Guidelines regarding the optimal cardiac management of patients with MD are lacking. The present article provides a summary of the pathophysiology of cardiac problems in patients with MD and provides a practical approach to contemporary cardiac monitoring and management of these patients with a focus on the prevention of complications related to conduction disturbances and arrhythmias. METHODS: A literature search was performed using PubMed and Medline. The keywords used in the search included "myotonic dystrophy", "cardiac manifestations", "heart", "arrhythmia", "pacemaker" and "defibrillator", all terms were used in combination. In addition, "myotonic dystrophy" was searched in conjunction with "electrophysiology", "electrocardiogram", "echocardiograph", "signal averaged electrocardiograph", "magnetic resonance imaging" and "exercise stress testing". The titles of all the articles revealed by the search were screened for relevance. The abstracts of relevant titles were read and those articles which concerned the cardiac manifestations of myotonic dystrophy or the investigation and management of cardiac manifestations underwent a full manuscript review.


Disease Management , Heart Diseases/diagnosis , Myotonic Dystrophy/diagnosis , Myotonic Dystrophy/therapy , Animals , Echocardiography/methods , Electrocardiography/methods , Heart Diseases/epidemiology , Heart Diseases/therapy , Humans
9.
Open Heart ; 1(1): e000030, 2014.
Article En | MEDLINE | ID: mdl-25332789

OBJECTIVES: Patients with schizophrenia treated with clozapine are at risk of acute myocarditis and dilated cardiomyopathy. However, there are no data on the prevalence of subclinical cardiomyopathy or its associations. METHODS: 100 consecutive patients with schizophrenia treated with clozapine for >1 year and without a history of cardiac pathology (group 1), 21 controls with a history of schizophrenia treated with non-clozapine antipsychotics for >1 year (group 2) and 20 controls without schizophrenia (group 3) were studied. Comprehensive evaluation by clinical examination, ECG, transthoracic echocardiography including left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) and biochemical profiles were performed. RESULTS: Patients with schizophrenia were of similar age, but had higher body mass index (BMI), rates of smoking and hyperlipidaemia than controls. Patients with schizophrenia had received clozapine or non-clozapine antipsychotics for a mean duration of 6.8±5.3 and 9.7±6.1 years, respectively. Patients taking clozapine demonstrated globally impaired LVEF (58.3%: group 1 vs 62.2%: group 2 vs 64.8%: group 3, p<0.001) and GLS (-16.7%: group 1 vs -18.6%: group 2 vs -20.2%: group 3, p<0.001). Moreover, LVEF was <50% in 9/100 (9%) patients receiving clozapine and in non-clozapine schizophrenia patients or healthy controls, but this was not statistically significantly different (analysis of covariance, p=0.19). Univariate analysis in patients taking clozapine found that impaired LV was not predicted by high-sensitivity troponin T, but was associated with features of the metabolic syndrome (including increased triglycerides, low high-density lipoprotein cholesterol (HDL-C), high-sensitivity C reactive protein and BMI), elevated neutrophil count, elevated heart rate, smoking and N-terminal probrain natriuretic peptide. In patients taking clozapine, multivariable analysis identified elevated neutrophil count and low HDL-C as the only independent predictors of impaired GLS. CONCLUSIONS: Asymptomatic mild LV impairment is common in patients with schizophrenia receiving long-term clozapine treatment and is associated with neutrophilia and low HDL-C.

10.
Platelets ; 25(8): 639-42, 2014.
Article En | MEDLINE | ID: mdl-24245520

Extracellular matrix metalloproteinase inducer (EMMPRIN; CD147), which binds to the platelet-specific collagen receptor glycoprotein (GP) VI, is expressed in a range of cell types including platelets and leukocytes, and has been implicated in neoplastic disease and atherosclerotic coronary disease. Both CD147 and GPVI can be shed from cell membranes and detected in plasma. However, while the relationship between soluble CD147 (sCD147), soluble GPVI (sGPVI) and standard markers of platelet activation has received little attention, such analysis may help reveal pathways mediating release of sCD147. We investigated the relationship between sCD147 and platelet markers including sGPVI, soluble and platelet-bound CD62P (P-selectin), active αIIbß3 (assessed by PAC-1 binding) and platelet CD147 in 25 patients with stable angina pectoris (SAP), 13 patients with no coronary artery disease (CAD) and 10 healthy donors. Plasma levels of sCD147 significantly correlated with sGPVI (r = 0.46, p = .004), but did not correlate with any other platelet markers examined. Linear regression analysis identified that sCD147 levels could be predicted by sGPVI levels (ß = .445, p = 0.003) and age (ß = 0.304, p = 0.038), but were independent of potential clinical confounders such as CAD, diabetes and medication usage. As sCD147 strongly correlates with platelet-specific sGPVI, a common platelet source and/or mechanism of release may contribute to sCD147 levels in vivo.


Basigin/blood , Coronary Artery Disease/blood , Platelet Membrane Glycoproteins/metabolism , Biomarkers/blood , Female , Humans , Male , Middle Aged , Risk Factors
11.
Thromb Haemost ; 110(3): 523-33, 2013 Sep.
Article En | MEDLINE | ID: mdl-23740364

The clinical characteristics and long-term outcomes of patients presenting with acute pulmonary embolism (PE) during treatment with warfarin have not been described. Clinical details of all patients admitted to a tertiary institution from 2000-2007 with acute PE were retrieved retrospectively, baseline warfarin status and the international normalised ratio (INR) were recorded, and their outcomes tracked using a statewide death registry. Of 923 patients with clearly documented warfarin status included in this study, 83 (9%) were taking warfarin. Mean (± standard deviation) day-1 INR of those taking warfarin was 2.3 ± 0.9, with 67% of patients therapeutically anti-coagulated (INR ≥2.0) at presentation (49 patients with INR <2.5 and 34 with INR ≥2.5). Patients taking warfarin on admission were more likely to have heart failure, atrial fibrillation and valvular heart disease, with similar prevalence of malignancy and ischaemic heart disease, compared to patients not on warfarin. Total mortality of the cohort (mean follow-up 4.0 ± 2.5 years) was 31.6% (in-hospital mortality 1.5%), and was similar between warfarin and no warfarin groups. There was however a greater than four-fold increased risk of post-discharge death due to recurrent PE for the patients taking warfarin on admission (hazard ratio [HR] 4.43, 95% confidence interval [CI] 1.36-14.42, p=0.01). Among patients taking warfarin on admission, day-1 INR <2.5 significantly increased long-term all-cause mortality compared to INR ≥2.5 (adjusted HR 2.51, 95% CI 1.08-5.86, p=0.03). In conclusion, patients presenting with PE during treatment with warfarin have an increased risk of death from recurrent PE. Admission INR appears to have independent long-term prognostic importance in these patients.


Pulmonary Embolism/diagnosis , Warfarin/adverse effects , Warfarin/therapeutic use , Aged , Anticoagulants/therapeutic use , Atrial Fibrillation/complications , Female , Follow-Up Studies , Heart Diseases/pathology , Heart Failure , Humans , International Normalized Ratio , Male , Middle Aged , Prognosis , Proportional Hazards Models , Pulmonary Embolism/mortality , Recurrence , Retrospective Studies , Time Factors , Treatment Outcome , Venous Thrombosis/drug therapy
12.
Heart Lung Circ ; 22(7): 533-41, 2013 Jul.
Article En | MEDLINE | ID: mdl-23415708

BACKGROUND: Cardiovascular observational registries characterise patients and describe the manner and use of therapeutic strategies. They facilitate analyses on the quality of care among participating institutions and document variations in clinical practice which can be benchmarked against best practice recommendations. The Cooperative National Registry of Acute Coronary care, Guideline Adherence and Clinical Events (CONCORDANCE) is an Australian observational registry that describes management and outcomes in patients with acute coronary syndromes (ACS) and feeds back both performance and outcome measures to participating hospitals. METHODS: The CONCORDANCE registry has been designed within a comparative effectiveness research (CER) framework to collect and report data from hospitals located in geographically diverse regions of Australia. Information including patient demographics, presenting characteristics, past medical history, in-hospital management and outcomes at six months and two years are entered into a web-based database using an electronic clinical record form (eCRF). Individual hospital information is returned to the sites in a real time confidential report detailing information on key performance indicator (KPI) process measures and outcomes benchmarked against the aggregated study cohort. Governance rules ensure data security and protect patient and clinician confidentiality. Consistent with a CER framework, additional characteristics of the registry include: (a) the capacity to evaluate associations between the inter and intra hospital systems and the provision of evidence based care and outcomes, (b) ongoing data collection from representative hospitals which allow spatial and temporal analysis of change in practice and the application of treatment modalities in the real world setting and (c) the provision of a data spine for quality improvement strategies and practical clinical trials. CONCLUSION: The CONCORDANCE registry is a clinician-driven initiative describing clinical care for ACS patients admitted to Australian hospitals. The registry generates high quality data which is fed back to clinicians, and key stakeholders in ACS care. Using a CER approach, the registry describes the translation of randomised trial evidence into practice, and provides insights into strategies that could improve care and ultimately patient outcomes.


Acute Coronary Syndrome , Databases, Factual , Guideline Adherence , Acute Coronary Syndrome/epidemiology , Acute Coronary Syndrome/therapy , Australia , Cohort Studies , Evidence-Based Medicine/methods , Registries
13.
Int J Cardiol ; 167(4): 1343-6, 2013 Aug 20.
Article En | MEDLINE | ID: mdl-22534045

BACKGROUND: Patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndromes (ACS) are known to have poorer short-term prognosis compared to stable coronary artery (CAD) patients undergoing elective PCI. Few studies have made direct comparison of long-term mortality between ACS and stable CAD patients undergoing PCI. The aim of our study was to compare the long-term mortality following PCI between patients with ACS and those with stable CAD. METHODS: We examined consecutive patients undergoing PCI with stenting at a tertiary referral hospital. Clinical, angiographic and biochemical data were collected and analysed. The primary outcome was all-cause mortality retrieved from the Statewide Death Registry database. RESULTS: Included were 1923 consecutive PCI patients (970 stable CAD and 953 ACS). The mean follow-up time was 4.1 years ± 1.8 years. In-hospital mortality was 1.4% overall, seen exclusively in patients with ACS (n=28, 2.9%). Post-discharge mortality was 6.7% among patients with stable CAD and 10.5% for ACS (P<0.01). Multivariate predictors of post-discharge deaths for both groups included age (HR 1.08 per year, P<0.001) and impaired renal function (HR 2.49, P<0.001). Following adjustment for these factors, an ACS indication for PCI was not associated with greater post-discharge mortality (adjusted HR 1.18: 0.85-1.64, P=0.32). CONCLUSIONS: Patients undergoing PCI following an ACS have higher long-term mortality to those with stable CAD, which is potentially explained by a greater prevalence of comorbidities. This suggests that for the ACS population, contemporary interventional and medical management strategies may effectively and specifically counter the adverse prognostic impact of coronary instability and myocardial damage.


Acute Coronary Syndrome/mortality , Acute Coronary Syndrome/surgery , Coronary Artery Disease/mortality , Coronary Artery Disease/surgery , Percutaneous Coronary Intervention/mortality , Acute Coronary Syndrome/diagnosis , Aged , Cohort Studies , Coronary Artery Disease/diagnosis , Female , Follow-Up Studies , Humans , Male , Middle Aged , New South Wales/epidemiology , Percutaneous Coronary Intervention/trends , Registries , Time Factors , Treatment Outcome
15.
J Thromb Haemost ; 8(3): 472-81, 2010 Mar.
Article En | MEDLINE | ID: mdl-19995409

BACKGROUND AND OBJECTIVES: EMMPRIN (CD147) is a matrix metalloproteinase inducer present on leukocytes and recently identified on platelets in vitro. We examined platelet CD147 expression in vivo and in correlation with markers of platelet activation and coronary artery disease (CAD). PATIENTS/METHODS: This prospective observational study involved 70 subjects (55 patients with CAD and 15 controls). Platelet CD62P expression, PAC-1 expression, platelet-leukocyte aggregates and CD147 (both platelet and leukocyte) expression were assessed by flow cytometry, and soluble CD62P expression was assessed by enzyme-linked immunosorbent assay. A full blood count and high-sensitivity C-reactive protein test were performed. RESULTS: CD147 was expressed on 20.45% +/- 1.63% (mean +/- standard error of the mean) of circulating platelets, whereas CD62P and PAC-1 were expressed on 0.87% +/- 0.12% and 0.90% +/- 0.27% of platelets, respectively. Platelet CD147 expression correlated with CD62P expression (r = 0.359, P = 0.002), PAC-1 expression (r = 0.428, P < 0.001), leukocyte CD147 expression (monocyte, r = 0.416, P = 0.001; granulocyte, r = 0.434, P < 0.001), C-reactive protein level and neutrophil/lymphocyte ratio (NLR). CAD patients had significantly higher CD147 mean fluorescence intensity than controls on circulating platelets (2.41 +/- 0.14 vs. 2.87 +/- 0.09, P = 0.014), monocytes (8.57 +/- 1.20 vs. 12.3 +/- 0.57, P = 0.006) and granulocytes (4.30 +/- 0.65 vs. 6.50 +/- 0.34, P = 0.005). Age adjustment eliminated the association between platelet CD147 expression and CAD, but the association between leukocyte CD147 expression and CAD persisted. According to multivariate analysis, the independent predictors of platelet CD147 expression were monocyte CD147 expression, NLR and age. CONCLUSIONS: Platelet CD147 expression is evident in vivo and correlates moderately with traditional platelet activation markers and leukocyte CD147 expression. Platelet CD147 expression shows a stronger association with age, and leukocyte CD147 expression a stronger association with clinical CAD, suggesting differences in the regulation of platelet and leukocyte CD147 expression in vivo.


Basigin/blood , Blood Platelets/immunology , Coronary Artery Disease/immunology , Platelet Activation , Age Factors , Aged , Biomarkers/blood , C-Reactive Protein/analysis , Case-Control Studies , Coronary Artery Disease/blood , Dual Specificity Phosphatase 2/blood , Enzyme-Linked Immunosorbent Assay , Female , Flow Cytometry , Humans , Leukocytes/immunology , Linear Models , Male , Middle Aged , Multivariate Analysis , P-Selectin/blood , Prospective Studies
16.
Heart ; 94(7): 911-8, 2008 Jul.
Article En | MEDLINE | ID: mdl-18070952

OBJECTIVE: To investigate subacute cardiac toxicity in patients with normal baseline cardiac function following autologous haematopoietic stem cell transplantation. DESIGN: Prospective observational study. PATIENT AND METHODS: Thirty-two consecutive patients (mean (SD) age 60 (11) years) with normal left ventricular ejection fraction (LVEF >or=50%) undergoing autologous haematopoietic stem cell transplantation were studied. Transthoracic echocardiography (including colour tissue Doppler imaging-derived myocardial velocities, strain and strain rates), troponin-T and B-type natriuretic peptide (BNP) and clinical details were recorded at baseline, after conditioning chemotherapy and serially over 6 weeks from the day of transplantation. RESULTS: The mean (SD) LVEF at baseline was 62 (6)% and decreased to 55 (16)%, 6 weeks after transplantation (p = 0.007). Cardiac toxicity (>or=10% absolute decline of LVEF to an LVEF

Hematopoietic Stem Cell Transplantation/adverse effects , Ventricular Dysfunction, Left/etiology , Acute Disease , Aged , Antineoplastic Agents/adverse effects , Blood Flow Velocity , Echocardiography, Doppler , Female , Hematologic Neoplasms/therapy , Humans , Male , Middle Aged , Mitral Valve/physiopathology , Prospective Studies , Pulmonary Edema/etiology , Stroke Volume , Transplantation Conditioning/adverse effects , Transplantation Conditioning/methods , Ventricular Dysfunction, Left/diagnostic imaging , Ventricular Dysfunction, Left/physiopathology , Ventricular Function, Left
17.
J Leukoc Biol ; 82(5): 1115-25, 2007 Nov.
Article En | MEDLINE | ID: mdl-17675559

Membrane-activated complex 1 (Mac-1; CD11b/CD18) is a beta(2) integrin implicated in the pathophysiology of neutrophil-mediated tissue injury whose functional capacity is determined by stimulus-induced conformational activation rather than up-regulation. Mac-1 up-regulation and conformational activation, together with shedding of L-selectin, are reported after in vitro neutrophil activation. However, their regulation on circulating human neutrophils during acute inflammation is unclear. Using flow cytometry, we investigated neutrophil expression of Mac-1, its activation-reporter neo-epitope CBRM1/5, and L-selectin during the inflammatory stimulus of cardiac surgery. A subpopulation of circulating neutrophils expressed CBRM1/5 (CBRM1/5+) under basal conditions (6.28+/-2.59%) and was persistently expanded (9.95+/-4.0%-15.2+/-4.2%; P<0.0001) peri-operatively, whereas total CD11b expression increased only transiently, intra-operatively. L-selectin expression was unchanged on CBRM1/5+ neutrophils, and soluble L-selectin levels decreased intra-operatively (P<0.01), indicating that L-selectin was not shed. Increased CBRM1/5 expression without L-selectin loss or CD11b up-regulation was replicated in vitro by neutrophil stimulation with IL-8, C3a, and platelet-activating factor. Heparin, a known CD11b ligand, which is administered during cardiac surgery, markedly reduced neutrophil expression of conformationally active CD11b in vivo and in vitro, identifying a potential mechanism for its anti-inflammatory properties. We conclude that conformational activation of CD11b occurs on circulating neutrophils in vivo and can occur in the absence of CD11b up-regulation and L-selectin shedding.


Angina Pectoris/metabolism , CD11b Antigen/chemistry , CD11b Antigen/metabolism , L-Selectin/metabolism , Macrophage-1 Antigen/immunology , Neutrophils/metabolism , Adult , Aged , Aged, 80 and over , Angina Pectoris/immunology , Angina Pectoris/surgery , CD11b Antigen/genetics , Chronic Disease , Complement C3a/metabolism , Coronary Artery Bypass , Epitopes/immunology , Epitopes/metabolism , Female , Flow Cytometry , Heparin/pharmacology , Humans , Interleukin-8/metabolism , Macrophage-1 Antigen/metabolism , Male , Middle Aged , Neutrophil Activation , Platelet Activating Factor/metabolism , Prospective Studies , Protein Conformation , Signal Transduction
18.
J Thromb Haemost ; 5(5): 918-24, 2007 May.
Article En | MEDLINE | ID: mdl-17371486

BACKGROUND: Platelet activation is implicated in thrombotic disorders, but has not been described in acute clinical pulmonary embolism (PE). OBJECTIVES: To investigate the natural history of platelet activation in PE and associated markers of inflammation, thrombosis and cardiac dysfunction. METHODS: Thirty-five consecutive patients (age 62 +/-17 years) with acute PE were prospectively enrolled and followed for 6 months. Platelet activation was assessed by flow cytometry [measuring expression of platelet P-selectin, conformational activation of glycoprotein IIb/IIIa complex (PAC-1) and formation of platelet-leukocyte complexes] and by plasma soluble P-selectin. Platelet activation, right ventricular (RV) function (assessed as RV ejection area by transthoracic echocardiography), D-dimer and high-sensitivity C-reactive protein (hs-CRP) were measured at presentation and repeated over 6 months follow-up. RESULTS: Soluble P-selectin (56 +/-19 ng mL(-1), anovaP < 0.0001) and PAC-1 (1.5 +/- 1.8%, anovaP = 0.005) were mildly but significantly increased in patients with acute PE relative to healthy young men (soluble P-selectin 33 +/- 13 ng mL(-1), P < 0.001; PAC-1 binding 0.5 +/- 0.6%, P < 0.01) and age-matched controls (soluble P-selectin 31 +/- 9 ng mL(-1), P < 0.001; PAC-1 binding 0.4 +/-0.4%, P < 0.05). Platelet P-selectin expression and platelet-leukocyte complexes were not increased during acute PE. Echocardiographic RV ejection area correlated inversely with soluble P-selectin (r = -0.47, P = 0.007) and positively with platelet P-selectin (r = 0.49, P = 0.0007), suggesting P-selectin is shed from activated platelets in proportion to the severity of RV dysfunction. Elevated soluble P-selectin, D-dimer and hs-CRP demonstrated a time-dependent return to normal during 6 months follow-up. CONCLUSION: Platelet activation is evident after acute PE. Platelet activation correlates with the severity of RV dysfunction, and can persist for several months after acute PE.


Platelet Activation , Pulmonary Embolism/physiopathology , Acute Disease , Adult , Aged , Blood Platelets/metabolism , Flow Cytometry , Humans , Middle Aged , P-Selectin/blood
19.
Clin Endocrinol (Oxf) ; 66(2): 235-45, 2007 Feb.
Article En | MEDLINE | ID: mdl-17223994

BACKGROUND: Androgens have striking effects on skeletal muscle, but the effects on human cardiac muscle function are not well defined, neither has the role of metabolic activation (aromatization, 5alpha reduction) of testosterone on cardiac muscle been directly studied. OBJECTIVE: To assess the effects of testosterone and nandrolone, a non-amplifiable and non-aromatizable pure androgen, on cardiac muscle function in healthy young men. DESIGN: Double-blind, randomized, placebo-controlled, three-arm parallel group clinical trial. SETTING: Ambulatory care research centre. PARTICIPANTS: Healthy young men randomized into three groups of 10 men. INTERVENTION: Weekly intramuscular injections of testosterone (200 mg mixed esters), nandrolone (200 mg nandrolone decanoate) or matching (2 ml arachis oil vehicle) placebo for 4 weeks. MAIN OUTCOME MEASURES: Comprehensive measures of cardiac muscle function involving transthoracic cardiac echocardiography measuring myocardial tissue velocity, peak systolic strain and strain rates, and bioimpedance measurement of cardiac output and systematic vascular resistance. RESULTS: Left ventricular (LV) function (LV ejection fraction, LV modified TEI index), right ventricular (RV) function (ejection area, tricuspid annular systolic planar motion, RV modified TEI index) as well as cardiac afterload (mean arterial pressure, systemic vascular resistance) and overall cardiac contractility (stroke volume, cardiac output) were within age- and gender-specific reference ranges and were not significantly (P < 0.05) altered by either androgen or placebo over 4 weeks of treatment. Minor changes remaining within normal range were observed solely within the testosterone group for: increased LV end-systolic diameter (30 +/- 7 vs. 33 +/- 5 mm, P = 0.04) and RV end-systolic area (12.8 +/- 1.3 vs. 14.6 +/- 3.3 cm(2), P = 0.04), reduced LV diastolic septal velocity (Em, 9.5 +/- 2.6 vs. 8.7 +/- 2.0 cm/s, P = 0.006), increased LV filling pressure (E/Em ratio, 7.1 +/- 1.6 vs. 8.3 +/- 1.8, P = 0.02) and shortened PR interval on the electrocardiogram (167 +/- 13 vs. 154 +/- 12, P = 0.03). CONCLUSION: Four weeks of treatment with testosterone or nandrolone had no beneficial or adverse effects compared with placebo on cardiac function in healthy young men.


Anabolic Agents/pharmacology , Myocardial Contraction/drug effects , Nandrolone/pharmacology , Testosterone/pharmacology , Adult , Analysis of Variance , Cardiac Output/drug effects , Double-Blind Method , Electrocardiography/drug effects , Humans , Injections, Intramuscular , Luteinizing Hormone/blood , Male , Middle Aged , Stress, Mechanical , Systole , Testosterone/blood , Vascular Resistance/drug effects
...