We enrolled

in the study 24 HIV-infected patients (all male) who are followed as out-patients at the HIV clinic of our hospital. All of them had good functional status, with CD4 T-cell counts in excess of 200 cells/μL and an absence of any other AIDS-defining condition. None had received any vaccination in the previous 6 months. Participants with coronary artery disease, cerebrovascular disease, peripheral artery disease and systemic inflammatory disease were excluded from the study. Use of anti-inflammatory agents, including aspirin and corticosteroids, anticoagulants, antidiabetics and lipid-lowering drugs was also an exclusion criterion. Participants refrained from smoking, exercise and the consumption of caffeinated beverages

for at least 3 h prior check details to their first visit and until the end EPZ015666 supplier of the study. At inclusion, they underwent a standardized medical history and examination and a 12-lead electrocardiogram. Weight and height were measured and body mass index (BMI) was calculated. The study protocol complies with the Declaration of Helsinki and was approved by our Institutional Research Ethics Committee. All subjects gave written informed consent to participate. The study had a double-blind, sham procedure-controlled design. Participants were randomly assigned to the vaccine or sham procedure group in a 2:1 ratio. Endothelial function was measured and blood sampling was performed at baseline between 08:00 and 10:00 h. Subsequently, vaccination against the influenza A/H1N1 virus was performed in the vaccine group by intramuscular

injection. A volume of 0.5 mL of a monovalent, split inactivated Montelukast Sodium vaccine with a water-in-oil adjuvant (MF59) was used (Focetria; Novartis International AG, Basel, Switzerland). The sham procedure group was injected with an equal volume of normal saline. Upon completion of the study protocol, the participants who were allocated to the sham procedure group were vaccinated, according to guidelines. Participants returned to our clinic at 8 and 48 h post vaccination/sham procedure. Repeated measurements of endothelial function and blood sampling were performed [asymmetric dimethylarginine (ADMA) was measured only at baseline and at 8 h]. Flow-mediated dilatation (FMD) is used as an estimate of endothelial function. Endothelial function was measured by high-resolution vascular ultrasound (Agilent Sonos 5500; Hewlett-Packard, Andover, MA, USA) according to guidelines [15]. Briefly, endothelium-dependent FMD was determined by measuring the change in the diameter of the brachial artery for 2 min after reactive hyperaemia for 5 min. FMD was defined as the maximum percentage change in brachial artery diameter compared with baseline values, i.e. FMD=[(post-occlusion diameter−resting diameter)/resting diameter] × 100. Analyses were conducted offline by two different investigators blinded to subject treatment.