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1.
Sci Rep ; 13(1): 1744, 2023 02 16.
Article in English | MEDLINE | ID: mdl-36797274

ABSTRACT

The COVID-19 pandemic has exposed the vulnerability of ethnic minorities again. Health inequity within ethnic minorities has been explained by factors such as higher prevalence of underlying disease, restricted access to care, and lower vaccination rates. In this study, we investigated the effect of cultural tailoring of communicators and media outlets, respectively, on vaccine willingness in an influenza vaccination campaign in the Netherlands. A total of 1226 participants were recruited from two culturally non-tailored media outlets (Dutch newspaper and Facebook), and one media outlet tailored to a large community in the Netherlands with Indian ancestry. The participants from all three media outlets were randomly exposed to a vaccination awareness video delivered by a physician with an Indian or Dutch background, followed by an online survey. Cultural tailoring compared to cultural non-tailoring of communicators showed no difference in improvement of vaccine willingness (13.9% vs. 20.7% increment, respectively, p = 0.083). However, the media outlet tailored to the community with Indian ancestry, resulted in a higher improvement of vaccine willingness compared to non-tailored media outlets (46.7% vs. 14.7% increment, respectively, p < 0.001, unadjusted OR = 5.096). These results suggest that cultural tailoring of media outlets may be critical to effectively reach out to ethnic minorities to help optimize vaccination rates and improve general health.


Subject(s)
COVID-19 , Influenza Vaccines , Influenza, Human , Humans , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Pandemics/prevention & control , Immunization Programs , Vaccination
2.
Neth Heart J ; 29(11): 545-550, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34648125

ABSTRACT

The COVID-19 pandemic has spurred clinical and scientific interest in the cardiology community because of the significantly enhanced vulnerability of patients with underlying cardiac diseases. COVID-19 vaccination is therefore of vital importance to the patients we see in our clinics and hospitals every day and should be promoted by the medical community, especially cardiologists. In view of vaccine-preventable diseases, the association between influenza and cardiovascular complications has been widely investigated. Several studies have found a substantially elevated risk of hospital admission for acute myocardial infarction in the first 7 days after laboratory-confirmed influenza, with incidence ratios ranging from 6.05-8.89. The effectiveness of the influenza vaccine to protect against acute myocardial infarction is about 29%. This effectiveness is comparable to or even better than that of existing secondary preventive therapies, such as statins (prevention rate approximately 36%), antihypertensives (prevention rate approximately 15-18%), and smoking cessation (prevention rate approximately 26%). As the influenza season is rapidly approaching, this Point of View article serves as a call to action: Cardiologists should promote influenza vaccination and actively advice their patients to get the seasonal influenza vaccination.

3.
J Intern Med ; 279(1): 89-97, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26223343

ABSTRACT

BACKGROUND: Natriuretic peptides are currently used to predict mortality in patients with heart failure (HF). However, novel independent biomarkers are needed to improve risk stratification in these patients. We hypothesized that annexin A5 (anxA5) would be highly expressed by organs which are generally affected by HF and that circulating anxA5 levels would predict mortality in HF patients. METHODS: We prospectively determined the diagnostic value of anxA5, N-terminal pro-B-type natriuretic peptide (NT-proBNP), C-reactive protein (CRP) and estimated glomerular filtration rate (eGFR) to predict mortality in 180 HF patients during a median follow-up of 3.6 years. Studies were conducted with anxA5(-/-) mice to investigate the underlying mechanisms. RESULTS: AnxA5 levels were significantly elevated in HF patients compared to healthy control subjects. Cox regression analysis demonstrated that anxA5, NT-proBNP and eGFR all predict mortality independently. AnxA5 significantly improved the diagnostic efficiency of NT-proBNP alone (improvement of c-statistic from 0.662 to 0.705, P < 0.001) and also combined with eGFR and CRP (improvement of c-statistic from 0.675 to 0.738, P < 0.001) to predict mortality in the Cox regression model. Receiver operating characteristic curve analysis showed that anxA5 predicted 3-year survival (area under curve 0.708) with an optimal cut-off value of 2.24 ng mL(-1) . Using anxA5(-/-) mice, we demonstrated that anxA5 is highly expressed in organs that are often affected by HF including lung, kidney, liver and spleen. Lysis of these organs in vitro resulted in a marked and significant increase in anxA5 concentrations. CONCLUSION: AnxA5 improves the diagnostic efficiency of conventional biomarkers to predict mortality in HF patients. Whereas natriuretic peptides originate from the myocardium, high circulating anxA5 levels in patients with HF are likely to reflect peripheral organ damage secondary to HF.


Subject(s)
Annexin A5/blood , Heart Failure/mortality , Animals , Biomarkers/blood , C-Reactive Protein/analysis , Female , Forecasting , Glomerular Filtration Rate , Humans , Male , Mice , Mice, Inbred C57BL , Middle Aged , Natriuretic Peptide, Brain/blood , Peptide Fragments/blood , Prospective Studies , Regression Analysis
4.
IET Syst Biol ; 4(6): 393-408, 2010 Nov.
Article in English | MEDLINE | ID: mdl-21073238

ABSTRACT

The dynamical properties of distal and proximal gene regulatory elements are crucial to their functionality in gene regulatory networks. However, the multiplicity of regulatory interactions at control elements makes their theoretical and experimental characterisation difficult. Here a thermodynamic framework to describe gene regulation by distant enhancers via a chromatin mechanism is developed. In this mechanism transcription factors (TFs) modulate gene expression via shifts in the equilibrium between chromatin states. The designs of AND, OR, XOR and NAND two-input transcriptional gates for the chromatin mechanism are proposed and compared to similar gates based on the direct physical interactions of TFs with the transcriptional machinery. An algorithm is developed to estimate the thermodynamic parameters of chromatin mechanism gates from gene expression reporter data and applied to characterise the response function for the Gata2-3 enhancer in hematopoietic stem cells. In addition waiting-time distributions for transcriptionally active states were analysed to expose the biophysical differences between the contact and chromatin mechanisms. These differences can be experimentally observed in single-cell experiments and therefore can serve as a signature of the gene regulation mechanism. Taken together these results indicate the diverse functionality and unique features of the chromatin mechanism of combinatorial gene regulation.


Subject(s)
Enhancer Elements, Genetic , Gene Expression Regulation , Models, Genetic , Systems Biology/methods , Transcription, Genetic/genetics , Algorithms , Chromatin/chemistry , Chromatin/genetics , Chromatin/metabolism , Kinetics , Protein Binding , Stochastic Processes , Thermodynamics , Transcription Factors/metabolism
5.
J Physiol Pharmacol ; 61(2): 133-9, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20436213

ABSTRACT

Aging is associated with increased incidence of myocardial infarctions and impaired angiogenesis - new capillary blood vessel formation from preexisting vessels. The molecular mechanism(s) of aging-related impairment of angiogenesis are unknown. In the present study we focused on the mechanism of activation of the gene for vascular endothelial growth factor (VEGF - the most potent stimulator of angiogenesis) in young and aging myocardial microvascular endothelial cells (MMEC). Activation of VEGF gene in the cell nucleus is mediated in part by the transcription factor hypoxia-inducible factor 1 alpha (HIF1 alpha). In order to activate VEGF gene, HIF1 alpha must first be transported to the nucleus, but the mechanisms of this transport are unknown. We hypothesized that reduced VEGF gene activation and impaired angiogenesis in myocardium during aging can result from downregulation of the nuclear transport receptor - importin alpha that leads to decreased transport of HIF1 alpha to the nucleus. We examined in MMEC isolated from young (3 months of age) and aging (24 months old) Fisher F-344 rats: 1) in vitro angiogenesis; and 2) the expression of VEGF, importin alpha and HIF1 alpha. Aging MMEC exhibited a 3.7-fold reduction in angiogenesis and a corresponding reduction in VEGF (by 3-fold) and importin alpha (by 1.9-fold) levels compared to young MMEC. Aging MMEC also exhibited cytoplasmic accumulation (by 1.8-fold) of HIF1 alpha protein, reduced HIF1 alpha transport to the nucleus and decreased binding of HIF1 alpha protein to the VEGF gene promoter. This study is the first demonstration of the downregulation of importin alpha in aging MMEC and reduced nuclear transport of HIF1 alpha, which likely lead to decreased VEGF gene activation and impaired angiogenesis.


Subject(s)
Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Neovascularization, Physiologic , Vascular Endothelial Growth Factor A/metabolism , alpha Karyopherins/metabolism , Age Factors , Aging , Animals , Cell Nucleus/metabolism , Cytoplasm/metabolism , Down-Regulation , Endothelium, Vascular/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Microvessels/metabolism , Myocardium/metabolism , Protein Binding , Protein Transport , Rats , Rats, Inbred F344 , Vascular Endothelial Growth Factor A/genetics , alpha Karyopherins/genetics
6.
Q J Nucl Med Mol Imaging ; 53(1): 26-34, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19182725

ABSTRACT

Atherosclerosis still represents killer number one in industrialized nations, and is starting to have increased impact in developing countries. Atherosclerotic plaques are the net result of a complex interplay between vascular cholesterol deposition, inflammatory activity and extracellular matrix formation. The result is luminal narrowing of arteries, which may ultimately lead to compromised blood flow to essential body organs, most notoriously to the heart. Most of the cardiovascular events that are caused by atherosclerosis, such as acute myocardial infarction or stroke, are the result of a transition of so-called stable atherosclerotic plaques to vulnerable plaques, that are prone to rupture. The direct consequence of atherosclerotic plaque rupture is exposure of thrombogenic plaque constituents to the blood, leading to instant local thrombus formation. The formation of this localized thrombus may ultimately result in sudden obstruction of blood flow and consequent infarction of distal tissue. Clinical risk profiling methods, such as the Framingham and Procam risk scores, are reasonable predictors of myocardial infarction over a 10-year time-span. However, the challenge remains to identify those patients with a very high risk of suffering from myocardial infarction in the coming months. Imaging may provide the necessary diagnostic information to identify such individuals. The transition of stable atherosclerotic plaques to vulnerable plaques is typically heralded by inflammation, thinning of the overlying fibrous cap, and the presence of a large necrotic core. Apoptosis is linked to all of these features of plaque vulnerability, and may, therefore, provide uniquely useful targets for the identification of plaque vulnerability. In recent years, a number of molecular imaging technologies have been developed to image apoptosis, which will be discussed in this review. Further development of apoptosis imaging technologies may aid us in the years to come in the quest to identify patients with critical cardiovascular risks, to treat myocardial infarction in its imminent, instead of its evident phase.


Subject(s)
Annexin A5/analysis , Apoptosis , Atherosclerosis/diagnostic imaging , Atherosclerosis/pathology , Animals , Annexin A5/metabolism , Atherosclerosis/metabolism , Humans , Positron-Emission Tomography , Staining and Labeling , Tomography, Emission-Computed, Single-Photon
7.
BMJ Case Rep ; 2009: bcr2006097782, 2009.
Article in English | MEDLINE | ID: mdl-21687155
8.
Eur J Nucl Med Mol Imaging ; 34 Suppl 1: S86-98, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17551724

ABSTRACT

INTRODUCTION: Molecular imaging strives to visualise processes at the molecular and cellular level in vivo. Understanding these processes supports diagnosis and evaluation of therapeutic efficacy on an individual basis and thereby makes personalised medicine possible. APOPTOSIS AND MOLECULAR IMAGING: Apoptosis is a well-organised mode of cell suicide that plays a role in cardiovascular diseases (CVD). Apoptosis is associated with loss of cardiomyocytes following myocardial infarction, atherosclerotic plaque instability, congestive heart failure and allograft rejection of the transplanted heart. Thus, apoptosis constitutes an attractive target for molecular imaging of CVD. Our current knowledge about the molecular players and mechanisms underlying apoptosis offers a rich palette of potential molecular targets for molecular imaging. However, only a few have been successfully developed so far. AIMS: This review highlights aspects of the molecular machinery and biochemistry of apoptosis relevant to the development of molecular imaging probes. It surveys the role of apoptosis in four major areas of CVD and portrays the importance and future perspectives of apoptosis imaging. The annexin A5 imaging protocol is emphasised since it is the most advanced protocol to measure apoptosis in both preclinical and clinical studies.


Subject(s)
Apoptosis , Cardiovascular Diseases/diagnosis , Diagnostic Imaging/methods , Heart/diagnostic imaging , Molecular Probe Techniques , Myocardium/pathology , Humans , Radionuclide Imaging
11.
Z Kardiol ; 93(2): 97-102, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14963674

ABSTRACT

Thrombosis of the coronary artery following plaque rupture is the commonest substrate of acute coronary events. The detection of atherosclerotic plaques prone to rupture would allow identifying patients at risk for acute coronary events and aggressive intervention. It has been assumed that the plaque morphology happens to be the major determinant for clinical outcome. The risk of plaque rupture depends upon the prevalence of plaques that have a large lipid core, a thin fibrous cap, and a dense inflammation of the fibrous cap. Evaluating monocytes and the lipid core and their proportions in the atherosclerotic lesion by novel radionuclide imaging strategies may predict a likelihood of an acute coronary event.


Subject(s)
Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/immunology , Coronary Thrombosis/diagnostic imaging , Coronary Thrombosis/immunology , Macrophages/immunology , Monocytes/immunology , Animals , Coronary Artery Disease/drug therapy , Coronary Artery Disease/pathology , Coronary Thrombosis/pathology , Coronary Thrombosis/prevention & control , Coronary Vessels/immunology , Coronary Vessels/pathology , Endothelium, Vascular/diagnostic imaging , Endothelium, Vascular/immunology , Humans , Macrophages/pathology , Monocytes/pathology , Radionuclide Imaging , Risk
12.
Circulation ; 109(1): 97-102, 2004 Jan 06.
Article in English | MEDLINE | ID: mdl-14676147

ABSTRACT

BACKGROUND: Although hypercholesterolemia is a well-established risk factor for coronary artery disease, little is known regarding its direct effects on cardiac function. METHODS AND RESULTS: We examined the effects of cholesterol feeding (0.5%) on cardiac function in rabbits. After 10 weeks, both systolic shortening and diastolic relaxation rates were impaired without any change in aortic pressure or ventricular hypertrophy. However, sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA)-2 mRNA levels were reduced within 4 days after initiation of cholesterol feeding. After this effect, SERCA-2 protein and SERCA-mediated Ca uptake into sarcoplasmic reticulum vesicles were impaired, and the ratio of MHC-beta to MHC-alpha mRNA increased 5-fold. Suppression of the SERCA-2 message correlated temporally with enrichment of the cardiac sarcolemma with cholesterol. CONCLUSIONS: These data demonstrate that dietary hypercholesterolemia induces a "cholesterol cardiomyopathy" characterized by systolic and diastolic dysfunction. These alterations were independent of vascular disease and demonstrate a dietary link to cardiac dysfunction.


Subject(s)
Cholesterol, Dietary/adverse effects , Diastole , Hypercholesterolemia/physiopathology , Systole , Ventricular Dysfunction, Left/etiology , Animals , Calcium-Transporting ATPases/metabolism , Cholesterol/metabolism , Hypercholesterolemia/complications , Hypercholesterolemia/metabolism , Hypercholesterolemia/pathology , Myocardium/metabolism , Myocardium/pathology , Myosin Heavy Chains/metabolism , Organ Size , RNA, Messenger/metabolism , Rabbits , Sarcolemma/metabolism , Sarcoplasmic Reticulum Calcium-Transporting ATPases , Ventricular Dysfunction, Left/metabolism , Ventricular Dysfunction, Left/pathology
13.
Nat Med ; 7(12): 1347-52, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11726976

ABSTRACT

Heart transplant rejection is characterized pathologically by myocyte necrosis and apoptosis associated with interstitial mononuclear cell infiltration. Any one of these components can be targeted for noninvasive detection of transplant rejection. During apoptotic cell death, phosphatidylserine, a phospholipid that is normally confined to the inner leaflet of cell membrane bilayer, gets exteriorized. Technetium-99m-labeled annexin-V, an endogenous protein that has high affinity for binding to phosphatidylserine, has been administered intravenously for noninvasive identification of apoptotic cell death. In the present study of 18 cardiac allograft recipients, 13 patients had negative and five had positive myocardial uptake of annexin. These latter five demonstrated at least moderate transplant rejection and caspase-3 staining, suggesting apoptosis in their biopsy specimens. This study reveals the clinical feasibility and safety of annexin-V imaging for noninvasive detection of transplant rejection by targeting cell membrane phospholipid alterations that are commonly associated with the process of apoptosis.


Subject(s)
Annexin A5 , Graft Rejection/diagnostic imaging , Heart Transplantation/diagnostic imaging , Heart Transplantation/immunology , Organotechnetium Compounds , Radionuclide Imaging/methods , Adult , Aged , Apoptosis , Biological Transport , Female , Humans , Injections, Intravenous , Male , Middle Aged , Myocardium/immunology , Myocardium/pathology
16.
Curr Opin Cardiol ; 16(5): 285-92, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11584167

ABSTRACT

While the concept of plaque 'vulnerability' implies a propensity towards thrombosis, the term vulnerable was originally intended to provide a morphologic description consistent with plaques that are prone to rupture. It is now known that the etiology of coronary thrombi is diverse and can arise from entities of plaque erosion or calcified nodules. These findings have prompted the search for more definitive terminology to describe precursor lesions associated with rupture, now referred to as thin-cap fibroatheromas. This review focuses on the thin-cap fibroatheroma, as a specific cause of acute coronary syndromes. To put these issues into current perspective, we need to revisit some of the older literature describing plaque morphology in stable and unstable angina, acute myocardial infarction, and sudden coronary death. The morphology, frequency, and precise location of these thin-cap fibroatheromas are further discussed in detail. Potential mechanisms of fibrous cap thinning are also addressed, in particular emerging data, which suggests the role of cell death "apoptosis" in cap atrophy.


Subject(s)
Coronary Artery Disease/physiopathology , Acute Disease , Angina Pectoris/epidemiology , Angina Pectoris/etiology , Angina Pectoris/physiopathology , Coronary Artery Disease/epidemiology , Coronary Thrombosis/complications , Coronary Thrombosis/epidemiology , Coronary Thrombosis/physiopathology , Death, Sudden, Cardiac/epidemiology , Death, Sudden, Cardiac/etiology , Humans , Incidence , Rupture, Spontaneous/physiopathology
19.
J Control Release ; 75(1-2): 199-210, 2001 Jul 10.
Article in English | MEDLINE | ID: mdl-11451510

ABSTRACT

A novel and highly efficient method of in vitro gene transfection has been developed. This method employs direct intracytoplasmic gene delivery into embryonic cardiocytes using neutral cytoskeletal-antigen specific immunoliposomes (CSIL). These immunoliposomes target cardiocytes specifically under reversible hypoxic conditions. Two independent reporter genes, pGL2 and pSV-beta-galactosidase, were used to verify CSIL-transfection (CSIL-fection). The efficiency of CSIL-fection with firefly luciferase pGL2 vector was 30+ times greater than controls consisting of hypoxic cardiocytes treated with plain liposomes (PL) or normoxic cardiocytes treated with CSIL, PL or naked DNA. CSIL-fection was also compared to cationic liposome transfection. Net cationic liposome transfection appeared to be more efficient than CSIL-fection for pGL2 vectors. However, a smaller number of viable cells was observed in the cationic liposome treated cultures than in the CSIL treated cultures. Therefore, to determine whether more cells were transfected with cationic liposomes or CSIL, pSV-beta-galactosidase vector was used. CSIL-fection with pSV-beta-galactosidase vector produced at least 40 times more transfected cells than those transfected with cationic liposomes. No transfection with pSV-beta-galactosidase vectors was obtained with IgG-liposome, PL or naked DNA treatments. Targeted enhanced efficiency of transfection by this novel method could have practical therapeutic applications in the genetic modification of cells ex vivo that could then be reimplanted into patients for gene therapy.


Subject(s)
Cytoplasm/metabolism , Cytoskeleton/metabolism , Gene Targeting/methods , Transfection/methods , Animals , Cells, Cultured , DNA/administration & dosage , DNA/analysis , DNA/pharmacokinetics , Drug Carriers , Excipients , Genes, Reporter , Liposomes , Luciferases/genetics , Microscopy, Confocal , Microscopy, Electron , Microscopy, Fluorescence , Myocardium/cytology , Myocardium/metabolism , Myosins/immunology , Particle Size , Rats , beta-Galactosidase/genetics
20.
Eur J Nucl Med ; 28(5): 614-9, 2001 May.
Article in English | MEDLINE | ID: mdl-11383867

ABSTRACT

Perfusion imaging combined with pharmacological stress is the study of choice in patients with ischaemic heart disease who are incapable of exercising. Some medical conditions, however, can preclude the use of pharmacological stress. In these particular situations, availability of a diagnostic test which allows for the assessment of ischaemic territory at rest would be desirable. With the purpose of providing a marker of reversible ischaemia, we evaluated myocardial iodine-123 metaiodobenzylguanidine (MIBG) uptake in regions with fixed and reversible defects defined by exercise/rest perfusion study. Fifty-four male patients with ischaemic heart disease and previous myocardial infarction were studied by means of exercise/rest tetrofosmin and MIBG single-photon emission tomography (SPET). Regional tracer uptake was quantified and expressed as a percentage of maximum peak activity. Areas with denervated but perfused myocardium and areas with ischaemic myocardium were calculated. Regions with<75% of peak activity in the exercise perfusion study were divided into two groups according to whether the increase in peak activity in the respective rest study was >10% (reversible regional defect) or <10% (fixed regional defect). These percentages were compared with the percentages of the innervation study. The area of the innervation defect was significantly larger when the perfusion defect was reversible than when it was fixed. In regions with reversible perfusion defects, the size of the area of denervated but perfused myocardium was similar to the size of the area of ischaemic myocardium. In regions with reversible defects, the percentage of myocardial MIBG uptake was not significantly different from the percentage of tetrofosmin uptake at exercise, while it was significantly lower than the percentage of tetrofosmin uptake at rest. In regions with fixed defects, the percentage of myocardial MIBG uptake was significantly lower than the percentage of tetrofosmin uptake at exercise and at rest. In patients who developed angina during exercise test, the area of denervated but perfused myocardium was significantly larger than in patients without angina (4.1+/-2.4 vs 3.4+/-2.5, P=0.02). The same trend was observed with regard to the size of the innervation defect (8.6+/-2.4 vs 5.7+/-2.2, P=0.02). It is concluded that when the use of pharmacological stress is not possible in patients incapable of exercising, rest studies with MIBG combined with rest myocardial perfusion studies may be useful as a marker of reversible ischaemia.


Subject(s)
3-Iodobenzylguanidine , Exercise Test , Myocardial Ischemia/diagnostic imaging , Organophosphorus Compounds , Organotechnetium Compounds , Radiopharmaceuticals , Tomography, Emission-Computed, Single-Photon , Adult , Aged , Coronary Circulation , Heart/innervation , Humans , Male , Middle Aged , Myocardial Ischemia/physiopathology , Rest , Sympathetic Nervous System/physiopathology
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