Abdominal Aortic Aneurysms: Endovascular Options and Outcomes — Proliferating Therapy,But Effective?

Abdominal aortic aneurysm (AAA) has a reported prevalence rate of 1.4% in the US. AAA rupture accounts for an estimated 15,000 deaths per year, rendering it the 10th leading cause of death in men over the age of 55. Endovascular repair (EVR) has proliferated in the last two decades as an increasingly popular alternative to traditional open surgery, and is now the default treatment in the majority of centres worldwide. This review article outlines the evidence supporting this stance. The development of EVR is reviewed, alongside trends in utilisation of this therapy over time. The evidence for the relative short-term and long-term outcomes of EVR and open AAA repair is discussed, and ongoing controversies surrounding the use of EVR are considered.     

Development of a species-specific colorimetric-PCR assay for detection and species differentiation of Mycobacterium immunogenum and Mycobacterium chelonae and its comparison with quantitative real-time PCR for field metalworking fluids

Mycobacterium immunogenum and Mycobacterium chelonae are closely related species associated with occupational hypersensitivity pneumonitis (HP) and nosocomial infections. There is a need to develop specific and readily adaptable methods for detection and speciation of these agents. Here we report development of a probe-based colorimetric-PCR assay involving heat shock protein (hsp) gene amplification (228bp) and its detection in an ELISA-like reaction. A quantitative format of this assay was developed and validated on metalworking fluids (MWF). The assay showed a minimum detection limit of 10 fg genomic DNA or 1 mycobacterial cell, albeit with variations depending on type and composition of the MWF matrix. When applied to the field MWF samples, the developed assay was found to be comparable to the real-time PCR assay, and allowed direct speciation of MWF mycobacteria without sequencing and/or restriction pattern analysis. In conclusion, the developed colorimetric PCR allows detection and quantification of MWF mycobacteria without culturing and is the first probe-based assay for unambiguous differentiation between the two phylogenetically closely related species, M. immunogenum and M. chelonae. Considering that the assay offers high throughput format involving relatively simpler instrument infrastructure, it has a potential for applications in routine assessment of MWF mycobacteria in diagnostic and industrial laboratories.     

Does aggressive statin therapy offer improved cholesterol-independent benefits compared to conventional statin treatment?

There is currently intense research interest in the properties of HMG-CoA reductase inhibitors (statins) beyond their well-documented lipid-lowering action. Studies have consistently demonstrated that administration of statin therapy decreases levels of the inflammatory marker C-reactive protein (CRP), a marker associated with an increased risk of cardiovascular events. This effect appears to be independent of the extent of reduction in total or LDL-cholesterol. Statins also appear to improve endothelial dysfunction by increasing endothelium-dependent vasodilatation. There is also evidence that statins inhibit fibrin formation and thrombus development, an effect that which would be clinically beneficial following plaque fissure or rupture. Early preclinical and clinical evidence suggests that there are quantitative differences between statin regimens in terms of their cholesterol-independent properties. Trials comparing equipotent doses of different statins, based on lipid-lowering efficacy, have not reported any differences in cholesterol-independent properties. However, the current evidence base indicates that more aggressive statin regimens are associated with an enhanced anti-inflammatory effect. Intensive lipid-lowering using statin therapy generates a greater reduction in mortality than standard lipid management, and it is possible that enhanced cholesterol-independent effects may account for some of this excess benefit.     

Eplerenone in the Treatment of Polypoidal Choroidal Vasculopathy

Overactivation of mineralocorticoid receptor pathways has been implicated in the pathophysiology of central serous chorioretinopathy (CSCR). Recently, mineralocorticoid receptor antagonists such as eplerenone have demonstrated success in treating subretinal fluid in CSCR. This case demonstrates a patient who was initially presumed to have subretinal fluid secondary to CSCR and was started on a trial of oral eplerenone. It quickly became evident that her subretinal fluid was secondary to a peripapillary polypoidal choroidal vasculopathy network, but she demonstrated a significant improvement with oral eplerenone. To the authors'' knowledge, this is the first case of eplerenone use to treat polypoidal choroidal vasculopathy.Key Words: Eplerenone, Mineralocorticoid antagonist, Polypoidal choroidal vasculopathy