Biomedical subjects

Rita Huber

Publications and source records attributed to Rita Huber.

3 recordsLinked to original sources

PubMed2006

Gene expression in acute Stanford type A dissection: a comparative microarray study.

BACKGROUND: We compared gene expression profiles in acutely dissected aorta with those in normal control aorta. MATERIALS AND METHODS: Ascending aorta specimen from patients with an acute Stanford A-dissection were taken during surgery and compared with those from normal ascending aorta from multiorgan donors using the BD Atlas Human1.2 Array I, BD Atlas Human Cardiovascular Array and the Affymetrix HG-U133A GeneChip. For analysis only genes with strong signals of more than 70 percent of the mean signal of all spots on the array were accepted as being expressed. Quantitative real-time polymerase chain reaction (RT-PCR) was used to confirm regulation of expression of a subset of 24 genes known to be involved in aortic structure and function. RESULTS: According to our definition expression profiling of aorta tissue specimens revealed an expression of 19.1% to 23.5% of the genes listed on the arrays. Of those 15.7% to 28.9% were differently expressed in dissected and control aorta specimens. Several genes that encode for extracellular matrix components such as collagen IV alpha2 and -alpha5, collagen VI alpha3, collagen XIV alpha1, collagen XVIII alpha1 and elastin were down-regulated in aortic dissection, whereas levels of matrix metalloproteinases-11, -14 and -19 were increased. Some genes coding for cell to cell adhesion, cell to matrix signaling (e.g., polycystin1 and -2), cytoskeleton, as well as several myofibrillar genes (e.g., alpha-actinin, tropomyosin, gelsolin) were found to be down-regulated. Not surprisingly, some genes associated with chronic inflammation such as interleukin -2, -6 and -8, were up-regulated in dissection. CONCLUSION: Our results demonstrate the complexity of the dissecting process on a molecular level. Genes coding for the integrity and strength of the aortic wall were down-regulated whereas components of inflammatory response were up-regulated. Altered patterns of gene expression indicate a pre-existing structural failure, which is probably a consequence of insufficient remodeling of the aortic wall resulting in further aortic dissection.

Journal Article↗

PubMed2004

[Antiplatelet therapy in patients with peripheral arterial disease (PAD)].

Peripheral arterial disease (PAD) is not an uncommon but a commonly neglected condition by many medical practitioners. Its prevalence steadily increases with age. In Germany almost one fifth of the patients aged > 65 years suffer from it. With increasing life expectancy the prevalence of PAD seems to be on the increase. PAD is a manifestation of diffuse and severe atherosclerosis. A very strong association exists between PAD and other atherosclerotic disorders such as coronary artery disease (CAD) and cerebrovascular disease (CVD). PAD is an independent predictor of high mortality in patients with CAD. Smoking, diabetes mellitus and advancing age are the cardinal risk factors. A relatively small number of PAD patients lose limbs by amputation. Most patients with PAD die of either heart attacks or strokes and they die of the former conditions far earlier than controls. Numerous authors have reported activation of the coagulatory system in PAD, possibly because of the diffuse pattern of the disease. Platelet hyperactivity in PAD may play a role in the process that leads to complications and disease progression. Thus, antiplatelet treatment in these patients may be essential to reduce their high mortality rate. Antiplatelet therapy for prevention of secondary vascular events is the cornerstone of pharmacological intervention in PAD. Based on current evidence, treating patients with PAD with antiplatelet drugs appears to be effective in reducing the risk of coronary and cerebrovascular events, in maintaining arterial and graft patency, and in slowing progression of disease. On the other hand, several studies indicated, that platelets in patients with PAD are relatively aspirin-resistant. The data from the CAPRIE Trial suggest a clinically and statistically significant better risk reduction with clopidogrel than with aspirin in patients with PAD. Aspirin alone should no longer be considered the optimal therapy for PAD.

Arterial Occlusive Diseases↗

PubMed2004

[Management of patients with renal artery stenosis. Reappraisal of operative treatment].

Arterial hypertension is most often the first symptom of renal artery stenosis (RAS). Appropriate screening methods for the diagnostic workup of hypertension are colour-coded duplex ultrasound and captopril scintigraphy. Angiography (intraarterial digital subtraction angiography) represents the diagnostic "gold standard", which is the prerequisite for the selection of the most suitable therapeutic method. Atherosclerosis is the most common disease in elderly patients presenting with RAS. In younger patients, fibromuscular dysplasia is more frequent. Five main types with different prognosis and therapeutic indications can be classified. Rare causes of RAS are dissection, renal artery aneurysm with combined stenosis, and especially in children and adolescents middle aortic syndrome with hypoplasia of the visceral arteries. Every patient with RAS of hemodynamic relevance in the presence of hypertension should be treated, whereas therapeutic risk and benefit must be weighed up individually. Aims are the improvement of hypertension and the maintenance of renal function. Surgical techniques, which are described subsequently, are indicated in all patients who need further simultaneous treatment of the abdominal vessels (abdominal aortic aneurysm, aortoiliac or visceral artery stenosis or aneurysm, respectively). In atherosclerotic ostial stenoses, angioplasty (PTA) and open surgery (normally transaortic endarterectomy) are concurrent methods. In our experience, the long-term results of surgical reconstruction seem to be superior. Both procedures are subject to an ongoing randomized study in our department. The outcome of surgical treatment for RAS is satisfying, the operative risk especially in isolated renal artery lesions is negligible.

Adolescent↗