Red Blood Cell Distribution Width (RDW) and long-term survival in patients with ST Elevation Myocardial Infarction

Introduction

High RDW values are associated with adverse prognosis in many clinical conditions including short and medium term outcome of patients with ST Elevation Myocardial Infarction (STEMI). The aim of the present study was to evaluate the association between RDW and long term mortality in STEMI patients undergoing primary angioplasty (PPCI).

Material and methods

A cohort of 535 STEMI patients undergoing PPCI were divided into two groups (RDW > 14%, RDW ≤ 14%) using CHAID and CART methods. The association between RDW and 5-year all-cause mortality was assessed using Cox’s proportional hazards analysis.

Results

A total of 37 patients died during follow up of 5 years (mean: 1059, median: 1013, range 2–2130 days). RDW > 14% was associated with increased risk of all-cause mortality (HR = 5, CI 95% 2.7– 9.9, p < 0.001). In multivariate analysis, RDW > 14 remained significantly associated with increased risk for all-cause mortality (HR = 3.8, CI 95% 1.8– 7.99, p < 0.001). Patients with RDW above 14% did not have lower ejection fraction, higher CPK or more conventional risk factors.

Conclusion

RDW value above 14 is independently associated with increased long term all-cause mortality in patients with STEMI undergoing PPCI.     

A genetic risk score based on direct associations with coronary heart disease improves coronary heart disease risk prediction in the Atherosclerosis Risk in Communities (ARIC), but not in the Rotterdam and Framingham Offspring, Studies

ObjectiveMultiple studies have identified single-nucleotide polymorphisms (SNPs) that are associated with coronary heart disease (CHD). We examined whether SNPs selected based on predefined criteria will improve CHD risk prediction when added to traditional risk factors (TRFs).MethodsSNPs were selected from the literature based on association with CHD, lack of association with a known CHD risk factor, and successful replication. A genetic risk score (GRS) was constructed based on these SNPs. Cox proportional hazards model was used to calculate CHD risk based on the Atherosclerosis Risk in Communities (ARIC) and Framingham CHD risk scores with and without the GRS.ResultsThe GRS was associated with risk for CHD (hazard ratio [HR] = 1.10; 95% confidence interval [CI]: 1.07–1.13). Addition of the GRS to the ARIC risk score significantly improved discrimination, reclassification, and calibration beyond that afforded by TRFs alone in non-Hispanic whites in the ARIC study. The area under the receiver operating characteristic curve (AUC) increased from 0.742 to 0.749 (Δ = 0.007; 95% CI, 0.004–0.013), and the net reclassification index (NRI) was 6.3%. Although the risk estimates for CHD in the Framingham Offspring (HR = 1.12; 95% CI: 1.10–1.14) and Rotterdam (HR = 1.08; 95% CI: 1.02–1.14) Studies were significantly improved by adding the GRS to TRFs, improvements in AUC and NRI were modest.ConclusionAddition of a GRS based on direct associations with CHD to TRFs significantly improved discrimination and reclassification in white participants of the ARIC Study, with no significant improvement in the Rotterdam and Framingham Offspring Studies.     

On relaxations and aging of various glasses

Slow relaxation occurs in many physical and biological systems. "Creep" is an example from everyday life. When stretching a rubber band, for example, the recovery to its equilibrium length is not, as one might think, exponential: The relaxation is slow, in many cases logarithmic, and can still be observed after many hours. The form of the relaxation also depends on the duration of the stretching, the "waiting time." This ubiquitous phenomenon is called aging, and is abundant both in natural and technological applications. Here, we suggest a general mechanism for slow relaxations and aging, which predicts logarithmic relaxations, and a particular aging dependence on the waiting time. We demonstrate the generality of the approach by comparing our predictions to experimental data on a diverse range of physical phenomena, from conductance in granular metals to disordered insulators and dirty semiconductors, to the low temperature dielectric properties of glasses.     

Autonomous phagosomal degradation and antigen presentation in dendritic cells

Phagocytosis plays a critical role in both innate and adaptive immunity. Phagosomal fusion with late endosomes and lysosomes enhances proteolysis, causing degradation of the phagocytic content. Increased degradation participates in both innate protection against pathogens and the production of antigenic peptides for presentation to T lymphocytes during adaptive immune responses. Specific ligands present in the phagosomal cargo influence the rate of phagosome fusion with lysosomes, thereby modulating both antigen degradation and presentation. Using a combination of cell sorting techniques and single phagosome flow cytometry-based analysis, we found that opsonization with IgG accelerates antigen degradation within individual IgG-containing phagosomes, but not in other phagosomes present in the same cell and devoid of IgG. Likewise, IgG opsonization enhances antigen presentation to CD4(+) T lymphocytes only when antigen and IgG are present within the same phagosome, whereas cells containing phagosomes with either antigen or IgG alone failed to present antigen efficiently. Therefore, individual phagosomes behave autonomously, in terms of both cargo degradation and antigen presentation to CD4(+) T cells. Phagosomal autonomy could serve as a basis for the intracellular discrimination between self and nonself antigens, resulting in the preferential presentation of peptides derived from opsonized, nonself antigens.     

Dislocation-mediated growth of bacterial cell walls

Recent experiments have illuminated a remarkable growth mechanism of rod-shaped bacteria: proteins associated with cell wall extension move at constant velocity in circles oriented approximately along the cell circumference [Garner EC, et al., (2011) Science 333:222-225], [Domínguez-Escobar J, et al. (2011) Science 333:225-228], [van Teeffelen S, et al. (2011) PNAS 108:15822-15827]. We view these as dislocations in the partially ordered peptidoglycan structure, activated by glycan strand extension machinery, and study theoretically the dynamics of these interacting defects on the surface of a cylinder. Generation and motion of these interacting defects lead to surprising effects arising from the cylindrical geometry, with important implications for growth. We also discuss how long range elastic interactions and turgor pressure affect the dynamics of the fraction of actively moving dislocations in the bacterial cell wall.     

Gender impact on prognosis of acute coronary syndrome patients treated with drug-eluting stents

Women have a higher risk of adverse outcomes after percutaneous coronary intervention (PCI) than men. However, in acute coronary syndrome (ACS), long-term outcomes after contemporary PCI with drug-eluting stent (DES) have not been fully investigated. We aimed to test the impact of gender on outcomes in patients with ACS after PCI with DES. We analyzed all patients with ACS from the prospective NOBORI-2 trial who underwent PCI with a Nobori DES from 2008 through 2009 in 125 centers worldwide. End points of the study were target lesion failure, cardiac death, myocardial infarction (MI), and clinically driven target lesion revascularization, and major adverse cardiac events (composite of cardiac death, MI, and target vessel revascularization) at 1 year and yearly up to 5 years. There were 1,640 patients with ACS, 1,268 men (77%) and 372 women (23%). Compared to men, women were 5 years older and more frequently had co-morbidities such as diabetes mellitus and hypertension. There were no gender differences for cardiac death (1.3% vs 2.7%), MI (2.1% vs 3.2%), or target lesion revascularization (2.6% vs 3.8%) at 1 year after the procedure for men and women, respectively. The trend was the same at 2 years (cardiac death 2.0% vs 2.3%, MI 2.5% vs 3.5%, target lesion revascularization 3.2% vs 4.6%). Target lesion failure rates were 4.5% and 5.9% at 1 year and 5.7% and 7.3% at 2 years in men and women, respectively (p = NS). Multivariate analysis, which included age, hypertension, diabetes mellitus, and number of diseased vessels, showed that gender was not a predictor for outcome. There were no differences in bleeding or stent thrombosis rates. Relief from anginal symptoms was similar. The same rate of adherence to dual antiplatelet therapy was observed and reached 73% at 1 year and 31% at 2 years after the ACS event and PCI. In conclusion, although women had worse baseline characteristics, no differences in outcomes were observed between men and women treated for ACS with contemporary DES.