Relationship between soluble thrombomodulin in patients with intermittent claudication and critical ischemia

The Relationship between Endothelial Dysfunction and Endothelial Cell Markers in Peripheral Arterial Disease

INTRODUCTION

The endothelial function plays key roles in both promoting and protecting against atherosclerotic disease. Several methods, including peripheral arterial tonometry (PAT), have been reported to be useful for investigating endothelial dysfunction. Furthermore, the level of thrombomodulin (TM) is assumed to reflect the endothelial dysfunction. In the present study, we investigated endothelial dysfunction in patients with peripheral arterial disease (PAD) by measuring their TM levels, and evaluated the correlation between TM and various parameters.

MATERIALS AND METHODS

We measured the TM levels and performed PAT in 17 patients with PAD. We also recorded the patients' demographic information, including comorbidities, and investigated their hemodynamic status by measuring the ankle brachial pressure index (ABI). The PAT results were used to calculate the reactive hyperemia index (RHI), which reflected the patients' level of endothelial dysfunction.

RESULTS

The RHI and ABI values and the serum level of creatinine were found to be significantly correlated with the TM level (P = 0.040, 0.041 and 0.005, respectively). After setting an RHI value of 1.67 as the cut-off, the patients with RHI values of <1.67 were found to have significantly higher TM levels (median, 20.3 U/mL) than the patients with RHI values of ≥1.67 (median, 13.7 U/mL) (P = 0.023).

CONCLUSIONS

The degree of endothelial dysfunction, as calculated by the TM level, might influence the prognostic value of the RHI, which is determined by PAT. The measurement of the TM level and PAT might both be useful methods of measuring endothelial dysfunction in patients with PAD.

Predictors of walking capacity in peripheral arterial disease patients

OBJECTIVE

To estimate walking capacity in intermittent claudication patients through a prediction model based on clinical characteristics and the walking impairment questionnaire.

METHODS

The sample included 133 intermittent claudication patients of both genders aged between 30 and 80 years. Data regarding clinical characteristics, the walking impairment questionnaire and treadmill walking test performance were obtained. Multiple regression modeling was conducted to predict claudication onset distance and total walking distance using clinical characteristics (age, height, mass, body mass index, ankle brachial index lower, gender, history of smoking and co-morbid conditions) and walking impairment questionnaire responses. Comparisons of claudication onset distance and total walking distance measured during treadmill tests and estimated by a regression equation were performed using paired t-tests.

RESULTS

Co-morbid conditions (diabetes and coronary artery disease) and questions related to difficulty in walking short distances (walking indoors - such as around your house and walking 5 blocks) and at low speed (walking 1 block at average speed - usual pace) resulted in the development of new prediction models high significant for claudication onset distance and total walking distance (p<0.001). In addition, non-significant differences from the results obtained by the treadmill test and estimated by the current model (p>0.05) were observed.

CONCLUSION

The current study demonstrated that walking capacity can be adequately estimated based on co-morbid conditions and responses to the walking impairment questionnaire.

Oxidized low-density lipoprotein and ankle-brachial pressure index in patients with clinically evident peripheral arterial disease

OBJECTIVES

To investigate whether oxidized low-density lipoprotein is a suitable predictor of peripheral arterial disease severity. The role of oxidized low-density lipoprotein in the pathogenesis of atherosclerosis has already been investigated. Its relevance as a predictor of the appearance and worsening of coronary arterial disease is also well known. However, the same is not true regarding peripheral arterial disease.

METHOD

Eighty-five consecutive patients with an ankle-brachial pressure index (ABPI) < 0.9 and the presence of either intermittent claudication or critical lower leg ischemia were included. The plasma level of IgG autoantibodies against oxidized low-density lipoprotein was evaluated through an enzyme-linked immunosorbent assay. The results were categorized into quartiles according to the ankle-brachial pressure index (a marker of peripheral arterial disease severity), and significant differences were investigated with the Kruskal-Wallis test.

RESULTS

There was no significant difference between the quartiles for this population (p = 0.33). No correlation was found between the ankle-brachial pressure index and oxidized low-density lipoprotein levels in subjects with clinically evident peripheral arterial disease with a wide range of clinical manifestations.

CONCLUSIONS

Oxidized low-density lipoprotein is not a good predictor of peripheral arterial disease severity.

The protein C pathway in tissue inflammation and injury: pathogenic role and therapeutic implications

Inflammation and coagulation are closely linked interdependent processes. Under physiologic conditions, the tissue microcirculation functions in anticoagulant and anti-inflammatory fashions. However, when inflammation occurs, coagulation is also set in motion and actively participates in enhancing inflammation. Recently, novel and unexpected roles of hemostasis in the humoral and cellular components of innate immunity have been described. In particular, the protein C system, besides its well-recognized role in anticoagulation, plays a crucial role in inflammation. Indeed, the protein C system is now emerging as a novel participant in the pathogenesis of acute and chronic inflammatory diseases, such as sepsis, asthma, inflammatory bowel disease, atherosclerosis, and lung and heart inflammation, and may emerge as unexpected therapeutic targets for intervention.

The protein C pathway in tissue inflammation and injury: pathogenic role and therapeutic implications

Inflammation and coagulation are closely linked interdependent processes. Under physiologic conditions, the tissue microcirculation functions in anticoagulant and anti-inflammatory fashions. However, when inflammation occurs, coagulation is also set in motion and actively participates in enhancing inflammation. Recently, novel and unexpected roles of hemostasis in the humoral and cellular components of innate immunity have been described. In particular, the protein C system, besides its well-recognized role in anticoagulation, plays a crucial role in inflammation. Indeed, the protein C system is now emerging as a novel participant in the pathogenesis of acute and chronic inflammatory diseases, such as sepsis, asthma, inflammatory bowel disease, atherosclerosis, and lung and heart inflammation, and may emerge as unexpected therapeutic targets for intervention.