Biomedical subjects

Julian Halcox

Publications and source records attributed to Julian Halcox.

4 recordsLinked to original sources

PubMed2005

Endothelial function and dysfunction. Part I: Methodological issues for assessment in the different vascular beds: a statement by the Working Group on Endothelin and Endothelial Factors of the European Society of Hypertension.

An enormous number of studies in the last two decades have been devoted to investigating the role of the endothelium in cardiovascular diseases. Nonetheless, the optimal methodology for investigating the multifaceted aspects of endothelial dysfunction is still under debate. Biochemical markers, molecular genetic tests and invasive and non-invasive tools with and without pharmacological and physiological stimuli have been introduced. Furthermore newer pharmacological tools have been proposed. However, the application of these methodologies should fulfil a number of requirements in order to provide conclusive answers in this area of research. Thus, the most relevant methodological issues in the research on endothelial function and dysfunction are summarized in this paper.

Endothelium, Vascular↗

PubMed2005

Endothelial function and dysfunction. Part II: Association with cardiovascular risk factors and diseases. A statement by the Working Group on Endothelins and Endothelial Factors of the European Society of Hypertension.

Dysfunction of the vascular endothelium is a hallmark of most conditions that are associated with atherosclerosis and is therefore held to be an early feature in atherogenesis. However, the mechanisms by which endothelial dysfunction occurs in smoking, dyslipidaemia, hyperhomocysteinaemia, diabetes mellitus, arterial hypertension, cerebrovascular diseases, coronary artery disease and heart failure are complex and heterogeneous. Recent data indicate that endothelial dysfunction is often associated with erectile dysfunction, which can precede and predict cardiovascular disease in men. This paper will provide a concise overview of the mechanisms causing endothelial dysfunction in the different cardiovascular risk factors and disease conditions, and of the impact of the intervention measures and treatments.

Cardiovascular Diseases↗

PubMed2004

A comparison of echocardiography and magnetic resonance imaging in cardiovascular screening of adults with Turner syndrome.

The high mortality rate from aortic dissection of women with Turner syndrome (TS) achieving ovum donation pregnancies has highlighted the need for a refinement of cardiac screening protocols. Echocardiography and magnetic resonance imaging (MRI) are used to assess the risk factors, aortic root dilatation, bicuspid aortic valve, and coarctation, but the relative merits of each modality are unclear. Cardiovascular screening was performed in 128 unselected women with TS (mean age +/- SD, 31.1 +/- 8.5 yr) using echocardiography (n = 120) and MRI (n = 115) and in 36 age-matched normal control women. Clinical history, anthropometric measurements, blood pressure, and metabolic parameters were recorded. Echocardiography was normal in 53% of women with TS; MRI was normal in 34%. Aortic root dilatation was identified in 16% of women by echocardiography, 33% on MRI criteria, and 7% by both modalities. Height-adjusted echocardiographic aortic root dimensions were greater in TS than controls (2.90 vs. 2.62 cm; P = 0.010). Bicuspid aortic valve and increasing age were associated with greater aortic dimensions; the latter effect was more marked in TS than controls. On MRI, ascending aortic diameter was greater in TS than control women (2.83 vs. 2.52 cm; P = 0.029), but descending aortic diameter and ascending/descending aortic ratio were not, because these may be affected by the presence of coarctation. The two techniques are complementary and identify different aspects of cardiovascular pathology. Ascending/descending ratio on MRI circumvents issues of stature, but may be influenced by descending aortic abnormalities. We present reference ranges for absolute aortic dimensions in a TS population to aid future interpretation of these measurements.

Adult↗

PubMed2003

Increased serum levels of heat shock protein 70 are associated with low risk of coronary artery disease.

OBJECTIVE: Previous studies suggest that heat shock protein (HSP) 60 has a contributory role in atherosclerosis development. We examined whether circulating HSP70 protein and anti-HSP70 antibodies are associated with coronary artery disease (CAD). METHODS AND RESULTS: Blood samples from 421 patients (62% men, mean age 57 years) evaluated for CAD by coronary angiography were tested. Serum HSP70 was detectable in 67% of study subjects with levels ranging from 0.2 to 27.1 ng/mL (mean, 1.08; median, 0.5). HSP70 levels were higher in non-CAD patients than CAD patients (median, 0.72 versus 0.34; P=0.0006). Individuals with HSP70 levels above the median (0.5 ng/mL) had half the risk of CAD than individuals with levels below the median (adjusted odds ratio, 0.52; 95% confidence limit, 0.32 to 0.86). The association of high HSP70 levels with low CAD risk was independent of traditional CAD risk factors (P=0.011). Disease severity (number of diseased vessels) was also inversely associated with HSP70 protein levels (P=0.010). The adjusted odds ratio of having multivessel disease for patients with high HSP70 protein levels was 0.54 (95% confidence limit, 0.36 to 0.81). In contrast, no association between anti-HSP70 IgG seropositivity and the prevalence of CAD was found (P=0.916). CONCLUSIONS: These data provide the first evidence that high levels of human HSP70 are associated with the low CAD risk, probably through its multiple protective effects on a cell's response to stress.

Adult↗