Feasibility of Arteriograph 24 for evaluation of 24-hour pulse wave velocity and central blood pressure in patients with type 2 diabetes and non-diabetic controls.

The objective of this study was to assess the feasibility of the Arteriograph 24 device to measure 24-hour PWV and central systolic blood pressure (cSBP) in patients with type 2 diabetes (T2DM) and non-diabetic controls and compare daytime and nighttime characteristics in the two groups. Twenty-four-hour PWV and cSBP was measured in 58 patients with T2DM (mean age: 66 ±â€…9 years, 50% women, mean duration of T2DM: 7.8 ±â€…1.5 years) and 62 age- and sex-matched controls. Seventy percent of participants (71% T2DM patients and 69% controls) had sufficient readings to generate an acceptable 24-hour report (≥14 day and ≥7 night readings). Lower nocturnal than daytime PWV and cSBP were observed in both groups. Nocturnal PWV and cSBP dipping were attenuated in T2DM patients compared to controls (PWV: -0.3 ±â€…0.9 vs. -0.7 ±â€…0.9 m/s, P  = 0.04, cSBP: -8 ±â€…14 vs. -18 ±â€…18 mmHg, P  < 0.01). No group differences in PWV or cSBP were observed during daytime (T2D vs. controls, PWV: 9.2 ±â€…1.1 vs. 9.2 ±â€…1.3 m/s, P  = 0.99, cSBP: 133 ±â€…19 vs. 137 ±â€…25 mmHg, P  = 0.42) or nighttime (PWV: 8.9 ±â€…1.3 vs. 8.4 ±â€…1.3 m/s, P  = 0.14, cSBP 124 ±â€…20 vs. 118 ±â€…27 mmHg, P  = 0.26). The study findings indicate that the nocturnal dipping of PWV and cSBP is attenuated in T2DM patients. The significant number of missing measurements raises concerns regarding the clinical utility of the Arteriograph 24 device.

Ghrelin, growth hormone and insulin-like growth Factor-I levels in people with protein C deficiency.

The primary objective of this study was to examine if people with protein C deficiency, which is a natural anticoagulant and also an endogenous acyl ghrelin peptidase, have elevated circulating levels of acyl ghrelin. The clinical trial was conducted in a university hospital setting. People with protein C deficiency were identified and invited to participate by a specialized coagulation outpatient clinic. People with protein C deficiency were examined and compared to age, sex, and body mass index matched healthy controls with regards to acyl ghrelin, unacylated ghrelin, growth hormone (GH) and insulin-like growth-factor I (IGF-I) in a cross-sectional case-control study. Systemic levels of acyl ghrelin, desacyl ghrelin, acyl-to-desacyl ghrelin ratio, GH and IGF-I were similar in people with protein C deficiency and healthy controls. Despite a significant reduction of protein C in people with protein C deficiency, there was no difference in acyl ghrelin or the secondary end points unacylated ghrelin, GH, or IGF-I in people with protein C deficiency.

The Diameter of Retinal Arterioles Is Unaffected by Intravascular Administration of the Adenosine A2A Receptor Agonist Regadenoson in Normal Persons.

BACKGROUND: The neurotransmitter adenosine has been proposed to be involved in the pathogenesis of diabetic retinopathy, which may be due to the vasoactive properties of the compound. Previous studies have shown that adenosine can affect the tone of retinal arterioles in vitro to induce dilatation mediated by A2A and A2Breceptors and constriction mediated by A1 and A3 receptors. PURPOSE: To investigate effects of intravenous administration of the adenosine A2A receptor agonist regadenoson on the diameter of retinal vessels in vivo. METHOD: The diameter responses of larger retinal arterioles and venules were evaluated using the dynamic vessel analyser in 20 normal persons (age 22-31 years) after intravenous administration of the adenosine A2A receptor agonist regadenoson during exposure to systemic normoxia and hypoxia. RESULTS: The diameter of retinal arterioles and venules increased significantly during stimulation with flickering light (p < 0.0001). Regadenoson reduced the flicker-induced dilatation of venules during normoxia (p = 0.0006), but otherwise had no effect on vessel diameters (p > 0.08 for all comparisons). CONCLUSIONS: Intravenous administration of the adenosine A2A receptor agonist regadenoson had no significant effect on the diameter of retinal arterioles. Future studies should investigate differential effects of intra- and extravascular administration of adenosine receptor agonists on retinal vessels.