A curious case of a spontaneous infective native pseudoaneurysm of the internal carotid artery.

We present a case of a 77-year-old patient who presented with a stroke. She subsequently became unwell and was found to have a spontaneous infective native carotid artery pseudoaneurysm. The patient was managed conservatively as per her wishes. Despite the rarity of this clinical diagnosis, clinicians should be aware of the pathophysiology of this entity and the available literature on management.

Simvastatin plus nitric oxide synthase inhibition modulates remote organ damage following skeletal muscle ischemia-reperfusion injury.

UNLABELLED: Ischemia-reperfusion injury (IRI) to the lower extremities causes both local damage and serious dysfunction to remote organs, including lungs and kidneys. However, effective therapies are not available. This study aims to determine if simvastatin reduced the severity of remote damage following IRI. METHODS: Rats were given simvastatin before hind limb IRI. Lung and kidney tissues were assessed for neutrophil infiltration using myeloperoxidase assays and basement membrane damage by quantitative immunohistochemical measurement of collagen IV. The effect of nitric oxide synthase (NOS) inhibition on remote damage after IRI and simvastatin was assessed using the NOS inhibitor, L-NIO. RESULTS: Simvastatin (2 mg/kg) protected kidneys against IRI-induced neutrophil infiltration. Simvastatin also inhibited the IRI-induced activation of MMP-9 in the lungs. However, paradoxically, simvastatin exacerbated IRI-induced neutrophil infiltration into the lungs. IRI induced collagen IV degradation in the lungs but not in the kidneys. The degree of collagen breakdown in the lungs was significantly ameliorated by 2 mg/kg simvastatin. NOS inhibition markedly protected both the lungs and the kidneys against IRI-induced neutrophil infiltration but did not alter collagen IV degradation. Administration of simvastatin to L-Nio-treated animals enhanced the degree of protection against IRI-induced neutrophil infiltration in the kidneys but not in the lungs. CONCLUSIONS: Simvastatin protects against remote IRI-induced damage in the lungs and kidneys, suggesting statins may reduce the severity of IRI during major vascular surgery.

The role of statins in vascular disease.

BACKGROUND: Recent publications have highlighted the benefits of statins in non-cardiac occlusive disease but also the failure of vascular surgeons to recognise and treat the risk factors for atherosclerosis, in particular hypercholesterolaemia. The aim of this review is to clarify the current experimental and clinical evidence for the use of statins in vascular disease. METHODS: Literature compiled from an extensive search of Medline and the Cochrane database has been used for the basis of this review. RESULTS: Experimental and clinical evidence consistently reports that statins improve endothelial dysfunction, are anti-inflammatory, anti-proliferative, anti-thrombogenic and anti-proteolytic. These effects are known to inhibit atherogenesis and improve plaque stability. Independent groups support the use of statins in the prevention of both primary and secondary cardiac events. The National Stroke association recommends their use to reduce strokes following myocardial infarction and the Heart Protection Study reports benefits in patients with non-cardiac occlusive disease. CONCLUSIONS: There is substantial evidence advocating the use of statins in patients with clinically significant vascular disease. In the future this may evolve to include those patients at risk from neointimal hyperplasia, aneurysmal disease and ischaemia reperfusion injury.

Segmental nature of the porcine liver and its potential as a model for experimental partial hepatectomy.

BACKGROUND: In-depth knowledge of pig liver anatomy allows potential research into segmental liver resections and hepatic regeneration, as well as liver transplantation techniques. The segmental anatomy, however, remains largely unknown. This study aimed to delineate the segmental anatomy of the porcine liver in comparison with that of the human. METHODS: The segmental anatomy of the porcine liver was determined using acrylic injection casting of ex vivo pig livers, allowing the arterial, venous and biliary supply to be visualized directly. This was correlated using multi-slice computed tomography (CT) and three-dimensional reconstructions. RESULTS: Although the external morphology of the porcine liver differs from that of the human, the segmental anatomy is remarkably similar in term of its vascularity and biliary tree. CONCLUSION: Acrylic casting of the porcine liver accurately delineates the vascular and biliary anatomy, and is a useful tool for performing experimental liver surgery. The similarities between porcine and human segmental anatomy allow domestic swine to be used as a comparable model. Three-dimensional CT reconstructions can also accurately visualize the anatomy and may be used to perform virtual surgery, or to assess segmental volumes.

Up-regulation of MMP-2 and MMP-9 leads to degradation of type IV collagen during skeletal muscle reperfusion injury; protection by the MMP inhibitor, doxycycline.

OBJECTIVES: to determine the role of matrix metalloproteinases, MMP-2 and MMP-9, in reperfusion injury following skeletal muscle ischaemia and whether inhibition of MMPs by doxycycline protects against tissue damage. METHODS: rats were anaesthetised and a tourniquet applied to the proximal thigh to occlude blood flow. Four hours of ischaemia was followed by reperfusion for 0, 4, 24 or 72 h. Two further groups received doxycycline for 7 days prior to bilateral ischaemia and 24 h reperfusion. Skeletal muscle from both limbs, kidneys and lungs were harvested for zymography and immunohistochemical staining for type IV collagen. RESULTS: upregulation of MMP-2 and MMP-9 was detected by zymography in the ischaemic leg and lung but not in the kidney. Quantitative immunohistochemical analysis showed marked degradation of type IV collagen in reperfused muscle, lung and kidney. Doxycycline-treated rats showed significant preservation of type IV collagen in skeletal muscle and a trend towards preservation in kidney and lung. CONCLUSIONS: MMP-2 and MMP-9 are strongly upregulated in skeletal muscle ischaemia/reperfusion injury and are also upregulated in remote organs, leading to degradation of basement membranes. Inhibition of MMP activity may therefore be potentially therapeutically useful in reducing the severity of reperfusion injury.