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1.  Functional modeling in zebrafish demonstrates that the atrial-fibrillation-associated gene GREM2 regulates cardiac laterality, cardiomyocyte differentiation and atrial rhythm 
Disease Models & Mechanisms  2012;6(2):332-341.
SUMMARY
Atrial fibrillation (AF) is the most common cardiac arrhythmia and carries a significant risk of stroke and heart failure. The molecular etiologies of AF are poorly understood, leaving patients with limited therapeutic options. AF has been recognized as an inherited disease in almost 30% of patient cases. However, few genetic loci have been identified and the mechanisms linking genetic variants to AF susceptibility remain unclear. By sequencing 193 probands with lone AF, we identified a Q76E variant within the coding sequence of the bone morphogenetic protein (BMP) antagonist gremlin-2 (GREM2) that increases its inhibitory activity. Functional modeling in zebrafish revealed that, through regulation of BMP signaling, GREM2 is required for cardiac laterality and atrial differentiation during embryonic development. GREM2 overactivity results in slower cardiac contraction rates in zebrafish, and induction of previously identified AF candidate genes encoding connexin-40, sarcolipin and atrial natriuretic peptide in differentiated mouse embryonic stem cells. By live heart imaging in zebrafish overexpressing wild-type or variant GREM2, we found abnormal contraction velocity specifically in atrial cardiomyocytes. These results implicate, for the first time, regulators of BMP signaling in human AF, providing mechanistic insights into the pathogenesis of the disease and identifying potential new therapeutic targets.
doi:10.1242/dmm.010488
PMCID: PMC3597016  PMID: 23223679
2.  Prognostic Value of Contrast-enhanced Cardiac Magnetic Resonance Imaging in Patients with Newly Diagnosed Non-Ischemic Cardiomyopathy: Cohort Study 
PLoS ONE  2013;8(2):e57077.
Background
Owing to its variable course from asymptomatic cases to sudden death risk stratification is of paramount importance in newly diagnosed non-ischemic cardiomyopathy. We tested whether late gadolinium enhancement (LGE) assessed by cardiac magnetic resonance (CMR) imaging is a prognostic marker in consecutive patients with newly diagnosed non-ischemic cardiomyopathy.
Methods
We enrolled 185 patients who presented for evaluation of newly diagnosed non-ischemic cardiomyopathy. Coronary artery disease was excluded by coronary angiography. Following risk markers were additionally assessed: NYHA functional class (≥II), brain natriuretic peptide (>100 ng/l), troponin I (TnI, ≥0.03 µg/l), left ventricular ejection fraction (LVEF, ≤40%), left ventricular enddiastolic diameter (>55 mm) and QRS duration (>98 ms). Endpoint of the study was the composite of all-cause mortality, heart transplantation, aborted sudden death, sustained ventricular tachycardia or hospitalization due to decompensated heart failure within three years of follow-up.
Results
During median follow-up of 21 months, 54 patients (29.2%) reached the composite endpoint. Ninety-four of the 185 patients (50.8%) were judged LGE-positive. Prognosis of LGE-positive patients was significantly worse than that of LGE-negative patients (cumulative 3-year event rates of 67.4% in LGE-positive and 27.2% in LGE-negative patients, respectively; p = 0.021). However, in multivariable analysis, presence of LGE was not an independent predictor of outcome. Only LVEF ≤40% and TnI ≥0.03 µg/l were independent risk predictors of the composite endpoint yielding relative risks of 3.9 (95% CI 1.9–8.1; p<0.0001) and 2.2 (95% CI 1.2–4.0; p = 0.014), respectively.
Conclusions
In consecutive patients presenting with newly diagnosed non-ischemic cardiomyopathy, LGE-positive patients had worse prognosis. However, only traditional risk parameters like left ventricular performance and cardiac biomarkers but not presence of LGE were independent risk predictors.
doi:10.1371/journal.pone.0057077
PMCID: PMC3577793  PMID: 23437315
3.  Massive haemoptysis in an intravenous drug user with infective tricuspid valve endocarditis 
BMJ Case Reports  2010;2010:bcr1020092404.
Major causes of morbidity in intravenous drug users are infections. In infective endocarditis, the tricuspid valve is mainly involved. Masses can cause septic embolisms and, in rare cases, they are associated with mycotic aneurysms of pulmonary arteries that lead to severe haemorrhage.
We report the case of a young woman with a history of intravenous drug abuse and prolonged infective tricuspid valve endocarditis. Initially, echocardiography showed large masses on the anterior leaflet of the tricuspid valve and severe tricuspid regurgitation; blood cultures revealed staphylococcus and streptococcus species. Eight months after initial diagnosis, she presented with severe haemoptysis and fever. CT revealed a ruptured mycotic aneurysm of the right pulmonary artery. Lobectomy was performed immediately.
Postoperatively, the patient fully recovered. After continued antibiotic treatment, follow-up examinations showed negative echocardiographic findings and blood cultures results.
doi:10.1136/bcr.10.2009.2404
PMCID: PMC3027946  PMID: 22767369
4.  Nanolesions induced by heavy ions in human tissues: Experimental and theoretical studies 
Summary
The biological effects of energetic heavy ions are attracting increasing interest for their applications in cancer therapy and protection against space radiation. The cascade of events leading to cell death or late effects starts from stochastic energy deposition on the nanometer scale and the corresponding lesions in biological molecules, primarily DNA. We have developed experimental techniques to visualize DNA nanolesions induced by heavy ions. Nanolesions appear in cells as “streaks” which can be visualized by using different DNA repair markers. We have studied the kinetics of repair of these “streaks” also with respect to the chromatin conformation. Initial steps in the modeling of the energy deposition patterns at the micrometer and nanometer scale were made with MCHIT and TRAX models, respectively.
doi:10.3762/bjnano.3.64
PMCID: PMC3458601  PMID: 23019551
DNA repair; heavy ions; microdosimetry; Monte Carlo simulations; nanolesions; radiation-induced nanostructures
5.  Macrophage Migration Inhibitory Factor Is Enhanced in Acute Coronary Syndromes and Is Associated with the Inflammatory Response 
PLoS ONE  2012;7(6):e38376.
Background
Chronic inflammation promotes atherosclerosis in cardiovascular disease and is a major prognostic factor for patients undergoing percutaneous coronary intervention (PCI). Macrophage migration inhibitory factor (MIF) is involved in the progress of atherosclerosis and plaque destabilization and plays a pivotal role in the development of acute coronary syndromes (ACS). Little is known to date about the clinical impact of MIF in patients with symptomatic coronary artery disease (CAD).
Methods and Results
In a pilot study, 286 patients with symptomatic CAD (n = 119 ACS, n = 167 stable CAD) undergoing PCI were consecutively evaluated. 25 healthy volunteers served as control. Expression of MIF was consecutively measured in patients at the time of PCI. Baseline levels of interleukin 6 (IL-6), “regulated upon activation, normal T-cell expressed, and secreted” (RANTES) and monocyte chemoattractant protein-1 (MCP-1) were measured by Bio-Plex Cytokine assay. C-reactive protein (CRP) was determined by Immunoassay. Patients with ACS showed higher plasma levels of MIF compared to patients with stable CAD and control subjects (median 2.85 ng/mL, interquartile range (IQR) 3.52 versus median 1.22 ng/mL, IQR 2.99, versus median 0.1, IQR 0.09, p<0.001). Increased MIF levels were associated with CRP and IL-6 levels and correlated with troponin I (TnI) release (spearman rank coefficient: 0.31, p<0.001). Patients with ACS due to plaque rupture showed significantly higher plasma levels of MIF than patients with flow limiting stenotic lesions (p = 0.002).
Conclusion
To our knowledge this is the first study, demonstrating enhanced expression of MIF in ACS. It is associated with established inflammatory markers, correlates with the extent of cardiac necrosis marker release after PCI and is significantly increased in ACS patients with “culprit” lesions. Further attempts should be undertaken to characterize the role of MIF for risk assessment in the setting of ACS.
doi:10.1371/journal.pone.0038376
PMCID: PMC3367911  PMID: 22693633
6.  Stable Morphology, but Dynamic Internal Reorganisation, of Interphase Human Chromosomes in Living Cells 
PLoS ONE  2010;5(7):e11560.
Despite the distinctive structure of mitotic chromosomes, it has not been possible to visualise individual chromosomes in living interphase cells, where chromosomes spend over 90% of their time. Studies of interphase chromosome structure and dynamics use fluorescence in-situ hybridisation (FISH) on fixed cells, which potentially damages structure and loses dynamic information. We have developed a new methodology, involving photoactivation of labelled histone H3 at mitosis, to visualise individual and specific human chromosomes in living interphase cells. Our data revealed bulk chromosome volume and morphology are established rapidly after mitosis, changing only incrementally after the first hour of G1. This contrasted with the behaviour of specific loci on labelled chromosomes, which showed more progressive reorganisation, and revealed that “looping out” of chromatin from chromosome territories is a dynamic state. We measured considerable heterogeneity in chromosome decondensation, even between sister chromatids, which may reflect local structural impediments to decondensation and could potentially amplify transcriptional noise. Chromosome structure showed tremendous resistance to inhibitors of transcription, histone deacetylation and chromatin remodelling. Together, these data indicate steric constraints determine structure, rather than innate chromosome architecture or function-driven anchoring, with interphase chromatin organisation governed primarily by opposition between needs for decondensation and the space available for this to happen.
doi:10.1371/journal.pone.0011560
PMCID: PMC2903487  PMID: 20644634
7.  Is Serological Testing a Reliable Tool in Laboratory Diagnosis of Syphilis? Meta-Analysis of Eight External Quality Control Surveys Performed by the German Infection Serology Proficiency Testing Program 
Journal of Clinical Microbiology  2006;44(4):1335-1341.
The accuracy of diagnostic tests is critical for successful control of epidemic outbreaks of syphilis. The reliability of syphilis serology in the nonspecialist laboratory has always been questioned, but actual data dealing with this issue are sparse. Here, the results of eight proficiency testing sentinel surveys for diagnostic laboratories in Germany between 2000 and 2003 were analyzed. Screening tests such as Treponema pallidum hemagglutination assay (mean accuracy, 91.4% [qualitative], 75.4% [quantitative]), Treponema pallidum particle agglutination assay (mean accuracy, 98.1% [qualitative], 82.9% [quantitative]), and enzyme-linked immunosorbent assays (ELISAs) (mean qualitative accuracy, 95%) were more reliable than Venereal Disease Research Laboratory (VDRL) testing (mean accuracy, 89.6% [qualitative], 71.1% [quantitative]), the fluorescent treponemal antibody absorption test (FTA-ABS) (mean accuracy, 88% [qualitative], 65.8% [quantitative]), and immunoblot assays (mean qualitative accuracy, 87.3%). Clearly, immunoglobulin M (IgM) tests were more difficult to manage than IgG tests. False-negative results for samples that have been unambiguously determined to be IgM and anti-lipoid antibody positive accounted for 4.7% of results in the IgM ELISA, 6.9% in the VDRL test, 18.5% in the IgM FTA-ABS, and 23.0% in the IgM immunoblot assay. For negative samples, the mean percentage of false-positive results was 4.1% in the VDRL test, 5.4% in the IgM ELISA, 0.7% in the IgM FTA-ABS, and 1.4% in the IgM immunoblot assay. On average, 18.3% of participants misclassified samples from patients with active syphilis as past infection without indicating the need for further treatment. Moreover, 10.2% of laboratories wrongly reported serological evidence for active infection in samples from patients with past syphilis or in sera from seronegative blood donors. Consequently, the continuous participation of laboratories in proficiency testing and further standardization of tests is strongly recommended to achieve better quality of syphilis serology.
doi:10.1128/JCM.44.4.1335-1341.2006
PMCID: PMC1448642  PMID: 16597859
8.  CXCR4 Chemokine Receptor Mediates Prostate Tumor Cell Adhesion through α5 and β3 Integrins1 
Neoplasia (New York, N.Y.)  2006;8(4):290-301.
Abstract
The mechanisms leading to prostate cancer metastasis are not understood completely. Although there is evidence that the CXC chemokine receptor (CXCR) 4 and its ligand CXCL12 may regulate tumor dissemination, their role in prostate cancer is controversial. We examined CXCR4 expression and functionality, and explored CXCL12-triggered adhesion of prostate tumor cells to human endothelium or to extracellular matrix proteins laminin, collagen, and fibronectin. Although little CXCR4 was expressed on LNCaP and DU-145 prostate tumor cells, CXCR4 was still active, enabling the cells to migrate toward a CXCL12 gradient. CXCL12 induced elevated adhesion to the endothelial cell monolayer and to immobilized fibronectin, laminin, and collagen. Anti-CXCR4 antibodies or CXCR4 knock out significantly impaired CXCL12-triggered tumor cell binding. The effects observed did not depend on CXCR4 surface expression level. Rather, CXCR4-mediated adhesion was established by α5 and β3 integrin subunits and took place in the presence of reduced p38 and p38 phosphorylation. These data show that chemoattractive mechanisms are involved in adhesion processes of prostate cancer cells, and that binding of CXCL12 to its receptor leads to enhanced expression of α5 and β3 integrins. The findings provide a link between chemokine receptor expression and integrin-triggered tumor dissemination.
PMCID: PMC1600676  PMID: 16756721
Adhesion; CXCR4; CXCL12; integrins; prostate carcinoma cells
9.  Mycophenolate mofetil modulates adhesion receptors of the beta1 integrin family on tumor cells: impact on tumor recurrence and malignancy 
BMC Cancer  2005;5:4.
Background
Tumor development remains one of the major obstacles following organ transplantation. Immunosuppressive drugs such as cyclosporine and tacrolimus directly contribute to enhanced malignancy, whereas the influence of the novel compound mycophenolate mofetil (MMF) on tumor cell dissemination has not been explored. We therefore investigated the adhesion capacity of colon, pancreas, prostate and kidney carcinoma cell lines to endothelium, as well as their beta1 integrin expression profile before and after MMF treatment.
Methods
Tumor cell adhesion to endothelial cell monolayers was evaluated in the presence of 0.1 and 1 μM MMF and compared to unstimulated controls. beta1 integrin analysis included alpha1beta1 (CD49a), alpha2beta1 (CD49b), alpha3beta1 (CD49c), alpha4beta1 (CD49d), alpha5beta1 (CD49e), and alpha6beta1 (CD49f) receptors, and was carried out by reverse transcriptase-polymerase chain reaction, confocal microscopy and flow cytometry.
Results
Adhesion of the colon carcinoma cell line HT-29 was strongly reduced in the presence of 0.1 μM MMF. This effect was accompanied by down-regulation of alpha3beta1 and alpha6beta1 surface expression and of alpha3beta1 and alpha6beta1 coding mRNA. Adhesion of the prostate tumor cell line DU-145 was blocked dose-dependently by MMF. In contrast to MMF's effects on HT-29 cells, MMF dose-dependently up-regulated alpha1beta1, alpha2beta1, alpha3beta1, and alpha5beta1 on DU-145 tumor cell membranes.
Conclusion
We conclude that MMF possesses distinct anti-tumoral properties, particularly in colon and prostate carcinoma cells. Adhesion blockage of HT-29 cells was due to the loss of alpha3beta1 and alpha6beta1 surface expression, which might contribute to a reduced invasive behaviour of this tumor entity. The enhancement of integrin beta1 subtypes observed in DU-145 cells possibly causes re-differentiation towards a low-invasive phenotype.
doi:10.1186/1471-2407-5-4
PMCID: PMC545066  PMID: 15644133
10.  A Critical Role of Platelet Adhesion in the Initiation of Atherosclerotic Lesion Formation 
The contribution of platelets to the process of atherosclerosis remains unclear. Here, we show in vivo that platelets adhere to the vascular endothelium of the carotid artery in ApoE−/− mice before the development of manifest atherosclerotic lesions. Platelet–endothelial cell interaction involved both platelet glycoprotein (GP)Ibα and GPIIb-IIIa. Platelet adhesion to the endothelium coincides with inflammatory gene expression and preceded atherosclerotic plaque invasion by leukocytes. Prolonged blockade of platelet adhesion in ApoE−/− mice profoundly reduced leukocyte accumulation in the arterial intima and attenuated atherosclerotic lesion formation in the carotid artery bifurcation, the aortic sinus, and the coronary arteries. These findings establish the platelet as a major player in initiation of the atherogenetic process.
doi:10.1084/jem.20012044
PMCID: PMC2194025  PMID: 12370251
platelets; endothelium; atherosclerosis; integrin; glycoprotein Ib

Results 1-10 (10)